diff options
Diffstat (limited to 'drivers/tty/serial/samsung_tty.c')
| -rw-r--r-- | drivers/tty/serial/samsung_tty.c | 3118 |
1 files changed, 3118 insertions, 0 deletions
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c new file mode 100644 index 000000000..aa2c51b84 --- /dev/null +++ b/drivers/tty/serial/samsung_tty.c @@ -0,0 +1,3118 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver core for Samsung SoC onboard UARTs. + * + * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + */ + +/* Note on 2410 error handling + * + * The s3c2410 manual has a love/hate affair with the contents of the + * UERSTAT register in the UART blocks, and keeps marking some of the + * error bits as reserved. Having checked with the s3c2410x01, + * it copes with BREAKs properly, so I am happy to ignore the RESERVED + * feature from the latter versions of the manual. + * + * If it becomes aparrent that latter versions of the 2410 remove these + * bits, then action will have to be taken to differentiate the versions + * and change the policy on BREAK + * + * BJD, 04-Nov-2004 + */ + +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/init.h> +#include <linux/sysrq.h> +#include <linux/console.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/serial_core.h> +#include <linux/serial.h> +#include <linux/serial_s3c.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/cpufreq.h> +#include <linux/of.h> +#include <asm/irq.h> + +/* UART name and device definitions */ + +#define S3C24XX_SERIAL_NAME "ttySAC" +#define S3C24XX_SERIAL_MAJOR 204 +#define S3C24XX_SERIAL_MINOR 64 + +#ifdef CONFIG_ARM64 +#define UART_NR 12 +#else +#define UART_NR CONFIG_SERIAL_SAMSUNG_UARTS +#endif + +#define S3C24XX_TX_PIO 1 +#define S3C24XX_TX_DMA 2 +#define S3C24XX_RX_PIO 1 +#define S3C24XX_RX_DMA 2 + +/* flag to ignore all characters coming in */ +#define RXSTAT_DUMMY_READ (0x10000000) + +enum s3c24xx_port_type { + TYPE_S3C24XX, + TYPE_S3C6400, + TYPE_APPLE_S5L, +}; + +struct s3c24xx_uart_info { + const char *name; + enum s3c24xx_port_type type; + unsigned int port_type; + unsigned int fifosize; + unsigned long rx_fifomask; + unsigned long rx_fifoshift; + unsigned long rx_fifofull; + unsigned long tx_fifomask; + unsigned long tx_fifoshift; + unsigned long tx_fifofull; + unsigned int def_clk_sel; + unsigned long num_clks; + unsigned long clksel_mask; + unsigned long clksel_shift; + unsigned long ucon_mask; + + /* uart port features */ + + unsigned int has_divslot:1; +}; + +struct s3c24xx_serial_drv_data { + const struct s3c24xx_uart_info info; + const struct s3c2410_uartcfg def_cfg; + const unsigned int fifosize[UART_NR]; +}; + +struct s3c24xx_uart_dma { + unsigned int rx_chan_id; + unsigned int tx_chan_id; + + struct dma_slave_config rx_conf; + struct dma_slave_config tx_conf; + + struct dma_chan *rx_chan; + struct dma_chan *tx_chan; + + dma_addr_t rx_addr; + dma_addr_t tx_addr; + + dma_cookie_t rx_cookie; + dma_cookie_t tx_cookie; + + char *rx_buf; + + dma_addr_t tx_transfer_addr; + + size_t rx_size; + size_t tx_size; + + struct dma_async_tx_descriptor *tx_desc; + struct dma_async_tx_descriptor *rx_desc; + + int tx_bytes_requested; + int rx_bytes_requested; +}; + +struct s3c24xx_uart_port { + unsigned char rx_claimed; + unsigned char tx_claimed; + unsigned char rx_enabled; + unsigned char tx_enabled; + unsigned int pm_level; + unsigned long baudclk_rate; + unsigned int min_dma_size; + + unsigned int rx_irq; + unsigned int tx_irq; + + unsigned int tx_in_progress; + unsigned int tx_mode; + unsigned int rx_mode; + + const struct s3c24xx_uart_info *info; + struct clk *clk; + struct clk *baudclk; + struct uart_port port; + const struct s3c24xx_serial_drv_data *drv_data; + + /* reference to platform data */ + const struct s3c2410_uartcfg *cfg; + + struct s3c24xx_uart_dma *dma; + +#ifdef CONFIG_ARM_S3C24XX_CPUFREQ + struct notifier_block freq_transition; +#endif +}; + +static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport); + +/* conversion functions */ + +#define s3c24xx_dev_to_port(__dev) dev_get_drvdata(__dev) + +/* register access controls */ + +#define portaddr(port, reg) ((port)->membase + (reg)) +#define portaddrl(port, reg) \ + ((unsigned long *)(unsigned long)((port)->membase + (reg))) + +static u32 rd_reg(const struct uart_port *port, u32 reg) +{ + switch (port->iotype) { + case UPIO_MEM: + return readb_relaxed(portaddr(port, reg)); + case UPIO_MEM32: + return readl_relaxed(portaddr(port, reg)); + default: + return 0; + } + return 0; +} + +#define rd_regl(port, reg) (readl_relaxed(portaddr(port, reg))) + +static void wr_reg(const struct uart_port *port, u32 reg, u32 val) +{ + switch (port->iotype) { + case UPIO_MEM: + writeb_relaxed(val, portaddr(port, reg)); + break; + case UPIO_MEM32: + writel_relaxed(val, portaddr(port, reg)); + break; + } +} + +#define wr_regl(port, reg, val) writel_relaxed(val, portaddr(port, reg)) + +/* Byte-order aware bit setting/clearing functions. */ + +static inline void s3c24xx_set_bit(const struct uart_port *port, int idx, + unsigned int reg) +{ + unsigned long flags; + u32 val; + + local_irq_save(flags); + val = rd_regl(port, reg); + val |= (1 << idx); + wr_regl(port, reg, val); + local_irq_restore(flags); +} + +static inline void s3c24xx_clear_bit(const struct uart_port *port, int idx, + unsigned int reg) +{ + unsigned long flags; + u32 val; + + local_irq_save(flags); + val = rd_regl(port, reg); + val &= ~(1 << idx); + wr_regl(port, reg, val); + local_irq_restore(flags); +} + +static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port) +{ + return container_of(port, struct s3c24xx_uart_port, port); +} + +/* translate a port to the device name */ + +static inline const char *s3c24xx_serial_portname(const struct uart_port *port) +{ + return to_platform_device(port->dev)->name; +} + +static int s3c24xx_serial_txempty_nofifo(const struct uart_port *port) +{ + return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE; +} + +static void s3c24xx_serial_rx_enable(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + unsigned long flags; + unsigned int ucon, ufcon; + int count = 10000; + + spin_lock_irqsave(&port->lock, flags); + + while (--count && !s3c24xx_serial_txempty_nofifo(port)) + udelay(100); + + ufcon = rd_regl(port, S3C2410_UFCON); + ufcon |= S3C2410_UFCON_RESETRX; + wr_regl(port, S3C2410_UFCON, ufcon); + + ucon = rd_regl(port, S3C2410_UCON); + ucon |= S3C2410_UCON_RXIRQMODE; + wr_regl(port, S3C2410_UCON, ucon); + + ourport->rx_enabled = 1; + spin_unlock_irqrestore(&port->lock, flags); +} + +static void s3c24xx_serial_rx_disable(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + unsigned long flags; + unsigned int ucon; + + spin_lock_irqsave(&port->lock, flags); + + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~S3C2410_UCON_RXIRQMODE; + wr_regl(port, S3C2410_UCON, ucon); + + ourport->rx_enabled = 0; + spin_unlock_irqrestore(&port->lock, flags); +} + +static void s3c24xx_serial_stop_tx(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + struct s3c24xx_uart_dma *dma = ourport->dma; + struct circ_buf *xmit = &port->state->xmit; + struct dma_tx_state state; + int count; + + if (!ourport->tx_enabled) + return; + + switch (ourport->info->type) { + case TYPE_S3C6400: + s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM); + break; + case TYPE_APPLE_S5L: + s3c24xx_clear_bit(port, APPLE_S5L_UCON_TXTHRESH_ENA, S3C2410_UCON); + break; + default: + disable_irq_nosync(ourport->tx_irq); + break; + } + + if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) { + dmaengine_pause(dma->tx_chan); + dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state); + dmaengine_terminate_all(dma->tx_chan); + dma_sync_single_for_cpu(dma->tx_chan->device->dev, + dma->tx_transfer_addr, dma->tx_size, + DMA_TO_DEVICE); + async_tx_ack(dma->tx_desc); + count = dma->tx_bytes_requested - state.residue; + xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); + port->icount.tx += count; + } + + ourport->tx_enabled = 0; + ourport->tx_in_progress = 0; + + if (port->flags & UPF_CONS_FLOW) + s3c24xx_serial_rx_enable(port); + + ourport->tx_mode = 0; +} + +static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport); + +static void s3c24xx_serial_tx_dma_complete(void *args) +{ + struct s3c24xx_uart_port *ourport = args; + struct uart_port *port = &ourport->port; + struct circ_buf *xmit = &port->state->xmit; + struct s3c24xx_uart_dma *dma = ourport->dma; + struct dma_tx_state state; + unsigned long flags; + int count; + + dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state); + count = dma->tx_bytes_requested - state.residue; + async_tx_ack(dma->tx_desc); + + dma_sync_single_for_cpu(dma->tx_chan->device->dev, + dma->tx_transfer_addr, dma->tx_size, + DMA_TO_DEVICE); + + spin_lock_irqsave(&port->lock, flags); + + xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); + port->icount.tx += count; + ourport->tx_in_progress = 0; + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + s3c24xx_serial_start_next_tx(ourport); + spin_unlock_irqrestore(&port->lock, flags); +} + +static void enable_tx_dma(struct s3c24xx_uart_port *ourport) +{ + const struct uart_port *port = &ourport->port; + u32 ucon; + + /* Mask Tx interrupt */ + switch (ourport->info->type) { + case TYPE_S3C6400: + s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM); + break; + case TYPE_APPLE_S5L: + WARN_ON(1); // No DMA + break; + default: + disable_irq_nosync(ourport->tx_irq); + break; + } + + /* Enable tx dma mode */ + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK); + ucon |= S3C64XX_UCON_TXBURST_1; + ucon |= S3C64XX_UCON_TXMODE_DMA; + wr_regl(port, S3C2410_UCON, ucon); + + ourport->tx_mode = S3C24XX_TX_DMA; +} + +static void enable_tx_pio(struct s3c24xx_uart_port *ourport) +{ + const struct uart_port *port = &ourport->port; + u32 ucon, ufcon; + + /* Set ufcon txtrig */ + ourport->tx_in_progress = S3C24XX_TX_PIO; + ufcon = rd_regl(port, S3C2410_UFCON); + wr_regl(port, S3C2410_UFCON, ufcon); + + /* Enable tx pio mode */ + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(S3C64XX_UCON_TXMODE_MASK); + ucon |= S3C64XX_UCON_TXMODE_CPU; + wr_regl(port, S3C2410_UCON, ucon); + + /* Unmask Tx interrupt */ + switch (ourport->info->type) { + case TYPE_S3C6400: + s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD, + S3C64XX_UINTM); + break; + case TYPE_APPLE_S5L: + ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK; + wr_regl(port, S3C2410_UCON, ucon); + break; + default: + enable_irq(ourport->tx_irq); + break; + } + + ourport->tx_mode = S3C24XX_TX_PIO; + + /* + * The Apple version only has edge triggered TX IRQs, so we need + * to kick off the process by sending some characters here. + */ + if (ourport->info->type == TYPE_APPLE_S5L) + s3c24xx_serial_tx_chars(ourport); +} + +static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport) +{ + if (ourport->tx_mode != S3C24XX_TX_PIO) + enable_tx_pio(ourport); +} + +static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport, + unsigned int count) +{ + struct uart_port *port = &ourport->port; + struct circ_buf *xmit = &port->state->xmit; + struct s3c24xx_uart_dma *dma = ourport->dma; + + if (ourport->tx_mode != S3C24XX_TX_DMA) + enable_tx_dma(ourport); + + dma->tx_size = count & ~(dma_get_cache_alignment() - 1); + dma->tx_transfer_addr = dma->tx_addr + xmit->tail; + + dma_sync_single_for_device(dma->tx_chan->device->dev, + dma->tx_transfer_addr, dma->tx_size, + DMA_TO_DEVICE); + + dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan, + dma->tx_transfer_addr, dma->tx_size, + DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT); + if (!dma->tx_desc) { + dev_err(ourport->port.dev, "Unable to get desc for Tx\n"); + return -EIO; + } + + dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete; + dma->tx_desc->callback_param = ourport; + dma->tx_bytes_requested = dma->tx_size; + + ourport->tx_in_progress = S3C24XX_TX_DMA; + dma->tx_cookie = dmaengine_submit(dma->tx_desc); + dma_async_issue_pending(dma->tx_chan); + return 0; +} + +static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + struct circ_buf *xmit = &port->state->xmit; + unsigned long count; + + /* Get data size up to the end of buffer */ + count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); + + if (!count) { + s3c24xx_serial_stop_tx(port); + return; + } + + if (!ourport->dma || !ourport->dma->tx_chan || + count < ourport->min_dma_size || + xmit->tail & (dma_get_cache_alignment() - 1)) + s3c24xx_serial_start_tx_pio(ourport); + else + s3c24xx_serial_start_tx_dma(ourport, count); +} + +static void s3c24xx_serial_start_tx(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + struct circ_buf *xmit = &port->state->xmit; + + if (!ourport->tx_enabled) { + if (port->flags & UPF_CONS_FLOW) + s3c24xx_serial_rx_disable(port); + + ourport->tx_enabled = 1; + if (!ourport->dma || !ourport->dma->tx_chan) + s3c24xx_serial_start_tx_pio(ourport); + } + + if (ourport->dma && ourport->dma->tx_chan) { + if (!uart_circ_empty(xmit) && !ourport->tx_in_progress) + s3c24xx_serial_start_next_tx(ourport); + } +} + +static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport, + struct tty_port *tty, int count) +{ + struct s3c24xx_uart_dma *dma = ourport->dma; + int copied; + + if (!count) + return; + + dma_sync_single_for_cpu(dma->rx_chan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + ourport->port.icount.rx += count; + if (!tty) { + dev_err(ourport->port.dev, "No tty port\n"); + return; + } + copied = tty_insert_flip_string(tty, + ((unsigned char *)(ourport->dma->rx_buf)), count); + if (copied != count) { + WARN_ON(1); + dev_err(ourport->port.dev, "RxData copy to tty layer failed\n"); + } +} + +static void s3c24xx_serial_stop_rx(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + struct s3c24xx_uart_dma *dma = ourport->dma; + struct tty_port *t = &port->state->port; + struct dma_tx_state state; + enum dma_status dma_status; + unsigned int received; + + if (ourport->rx_enabled) { + dev_dbg(port->dev, "stopping rx\n"); + switch (ourport->info->type) { + case TYPE_S3C6400: + s3c24xx_set_bit(port, S3C64XX_UINTM_RXD, + S3C64XX_UINTM); + break; + case TYPE_APPLE_S5L: + s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON); + s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON); + break; + default: + disable_irq_nosync(ourport->rx_irq); + break; + } + ourport->rx_enabled = 0; + } + if (dma && dma->rx_chan) { + dmaengine_pause(dma->tx_chan); + dma_status = dmaengine_tx_status(dma->rx_chan, + dma->rx_cookie, &state); + if (dma_status == DMA_IN_PROGRESS || + dma_status == DMA_PAUSED) { + received = dma->rx_bytes_requested - state.residue; + dmaengine_terminate_all(dma->rx_chan); + s3c24xx_uart_copy_rx_to_tty(ourport, t, received); + } + } +} + +static inline const struct s3c24xx_uart_info + *s3c24xx_port_to_info(struct uart_port *port) +{ + return to_ourport(port)->info; +} + +static inline const struct s3c2410_uartcfg + *s3c24xx_port_to_cfg(const struct uart_port *port) +{ + const struct s3c24xx_uart_port *ourport; + + if (port->dev == NULL) + return NULL; + + ourport = container_of(port, struct s3c24xx_uart_port, port); + return ourport->cfg; +} + +static int s3c24xx_serial_rx_fifocnt(const struct s3c24xx_uart_port *ourport, + unsigned long ufstat) +{ + const struct s3c24xx_uart_info *info = ourport->info; + + if (ufstat & info->rx_fifofull) + return ourport->port.fifosize; + + return (ufstat & info->rx_fifomask) >> info->rx_fifoshift; +} + +static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport); +static void s3c24xx_serial_rx_dma_complete(void *args) +{ + struct s3c24xx_uart_port *ourport = args; + struct uart_port *port = &ourport->port; + + struct s3c24xx_uart_dma *dma = ourport->dma; + struct tty_port *t = &port->state->port; + struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port); + + struct dma_tx_state state; + unsigned long flags; + int received; + + dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state); + received = dma->rx_bytes_requested - state.residue; + async_tx_ack(dma->rx_desc); + + spin_lock_irqsave(&port->lock, flags); + + if (received) + s3c24xx_uart_copy_rx_to_tty(ourport, t, received); + + if (tty) { + tty_flip_buffer_push(t); + tty_kref_put(tty); + } + + s3c64xx_start_rx_dma(ourport); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport) +{ + struct s3c24xx_uart_dma *dma = ourport->dma; + + dma_sync_single_for_device(dma->rx_chan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + + dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan, + dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT); + if (!dma->rx_desc) { + dev_err(ourport->port.dev, "Unable to get desc for Rx\n"); + return; + } + + dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete; + dma->rx_desc->callback_param = ourport; + dma->rx_bytes_requested = dma->rx_size; + + dma->rx_cookie = dmaengine_submit(dma->rx_desc); + dma_async_issue_pending(dma->rx_chan); +} + +/* ? - where has parity gone?? */ +#define S3C2410_UERSTAT_PARITY (0x1000) + +static void enable_rx_dma(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + unsigned int ucon; + + /* set Rx mode to DMA mode */ + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(S3C64XX_UCON_RXBURST_MASK | + S3C64XX_UCON_TIMEOUT_MASK | + S3C64XX_UCON_EMPTYINT_EN | + S3C64XX_UCON_DMASUS_EN | + S3C64XX_UCON_TIMEOUT_EN | + S3C64XX_UCON_RXMODE_MASK); + ucon |= S3C64XX_UCON_RXBURST_1 | + 0xf << S3C64XX_UCON_TIMEOUT_SHIFT | + S3C64XX_UCON_EMPTYINT_EN | + S3C64XX_UCON_TIMEOUT_EN | + S3C64XX_UCON_RXMODE_DMA; + wr_regl(port, S3C2410_UCON, ucon); + + ourport->rx_mode = S3C24XX_RX_DMA; +} + +static void enable_rx_pio(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + unsigned int ucon; + + /* set Rx mode to DMA mode */ + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~S3C64XX_UCON_RXMODE_MASK; + ucon |= S3C64XX_UCON_RXMODE_CPU; + + /* Apple types use these bits for IRQ masks */ + if (ourport->info->type != TYPE_APPLE_S5L) { + ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK | + S3C64XX_UCON_EMPTYINT_EN | + S3C64XX_UCON_DMASUS_EN | + S3C64XX_UCON_TIMEOUT_EN); + ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT | + S3C64XX_UCON_TIMEOUT_EN; + } + wr_regl(port, S3C2410_UCON, ucon); + + ourport->rx_mode = S3C24XX_RX_PIO; +} + +static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport); + +static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id) +{ + unsigned int utrstat, received; + struct s3c24xx_uart_port *ourport = dev_id; + struct uart_port *port = &ourport->port; + struct s3c24xx_uart_dma *dma = ourport->dma; + struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port); + struct tty_port *t = &port->state->port; + struct dma_tx_state state; + + utrstat = rd_regl(port, S3C2410_UTRSTAT); + rd_regl(port, S3C2410_UFSTAT); + + spin_lock(&port->lock); + + if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) { + s3c64xx_start_rx_dma(ourport); + if (ourport->rx_mode == S3C24XX_RX_PIO) + enable_rx_dma(ourport); + goto finish; + } + + if (ourport->rx_mode == S3C24XX_RX_DMA) { + dmaengine_pause(dma->rx_chan); + dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state); + dmaengine_terminate_all(dma->rx_chan); + received = dma->rx_bytes_requested - state.residue; + s3c24xx_uart_copy_rx_to_tty(ourport, t, received); + + enable_rx_pio(ourport); + } + + s3c24xx_serial_rx_drain_fifo(ourport); + + if (tty) { + tty_flip_buffer_push(t); + tty_kref_put(tty); + } + + wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT); + +finish: + spin_unlock(&port->lock); + + return IRQ_HANDLED; +} + +static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + unsigned int ufcon, ch, flag, ufstat, uerstat; + unsigned int fifocnt = 0; + int max_count = port->fifosize; + + while (max_count-- > 0) { + /* + * Receive all characters known to be in FIFO + * before reading FIFO level again + */ + if (fifocnt == 0) { + ufstat = rd_regl(port, S3C2410_UFSTAT); + fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat); + if (fifocnt == 0) + break; + } + fifocnt--; + + uerstat = rd_regl(port, S3C2410_UERSTAT); + ch = rd_reg(port, S3C2410_URXH); + + if (port->flags & UPF_CONS_FLOW) { + int txe = s3c24xx_serial_txempty_nofifo(port); + + if (ourport->rx_enabled) { + if (!txe) { + ourport->rx_enabled = 0; + continue; + } + } else { + if (txe) { + ufcon = rd_regl(port, S3C2410_UFCON); + ufcon |= S3C2410_UFCON_RESETRX; + wr_regl(port, S3C2410_UFCON, ufcon); + ourport->rx_enabled = 1; + return; + } + continue; + } + } + + /* insert the character into the buffer */ + + flag = TTY_NORMAL; + port->icount.rx++; + + if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) { + dev_dbg(port->dev, + "rxerr: port ch=0x%02x, rxs=0x%08x\n", + ch, uerstat); + + /* check for break */ + if (uerstat & S3C2410_UERSTAT_BREAK) { + dev_dbg(port->dev, "break!\n"); + port->icount.brk++; + if (uart_handle_break(port)) + continue; /* Ignore character */ + } + + if (uerstat & S3C2410_UERSTAT_FRAME) + port->icount.frame++; + if (uerstat & S3C2410_UERSTAT_OVERRUN) + port->icount.overrun++; + + uerstat &= port->read_status_mask; + + if (uerstat & S3C2410_UERSTAT_BREAK) + flag = TTY_BREAK; + else if (uerstat & S3C2410_UERSTAT_PARITY) + flag = TTY_PARITY; + else if (uerstat & (S3C2410_UERSTAT_FRAME | + S3C2410_UERSTAT_OVERRUN)) + flag = TTY_FRAME; + } + + if (uart_handle_sysrq_char(port, ch)) + continue; /* Ignore character */ + + uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN, + ch, flag); + } + + tty_flip_buffer_push(&port->state->port); +} + +static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id) +{ + struct s3c24xx_uart_port *ourport = dev_id; + struct uart_port *port = &ourport->port; + + spin_lock(&port->lock); + s3c24xx_serial_rx_drain_fifo(ourport); + spin_unlock(&port->lock); + + return IRQ_HANDLED; +} + +static irqreturn_t s3c24xx_serial_rx_irq(int irq, void *dev_id) +{ + struct s3c24xx_uart_port *ourport = dev_id; + + if (ourport->dma && ourport->dma->rx_chan) + return s3c24xx_serial_rx_chars_dma(dev_id); + return s3c24xx_serial_rx_chars_pio(dev_id); +} + +static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport) +{ + struct uart_port *port = &ourport->port; + struct circ_buf *xmit = &port->state->xmit; + int count, dma_count = 0; + + count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); + + if (ourport->dma && ourport->dma->tx_chan && + count >= ourport->min_dma_size) { + int align = dma_get_cache_alignment() - + (xmit->tail & (dma_get_cache_alignment() - 1)); + if (count - align >= ourport->min_dma_size) { + dma_count = count - align; + count = align; + } + } + + if (port->x_char) { + wr_reg(port, S3C2410_UTXH, port->x_char); + port->icount.tx++; + port->x_char = 0; + return; + } + + /* if there isn't anything more to transmit, or the uart is now + * stopped, disable the uart and exit + */ + + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + s3c24xx_serial_stop_tx(port); + return; + } + + /* try and drain the buffer... */ + + if (count > port->fifosize) { + count = port->fifosize; + dma_count = 0; + } + + while (!uart_circ_empty(xmit) && count > 0) { + if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull) + break; + + wr_reg(port, S3C2410_UTXH, xmit->buf[xmit->tail]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + count--; + } + + if (!count && dma_count) { + s3c24xx_serial_start_tx_dma(ourport, dma_count); + return; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (uart_circ_empty(xmit)) + s3c24xx_serial_stop_tx(port); +} + +static irqreturn_t s3c24xx_serial_tx_irq(int irq, void *id) +{ + struct s3c24xx_uart_port *ourport = id; + struct uart_port *port = &ourport->port; + + spin_lock(&port->lock); + + s3c24xx_serial_tx_chars(ourport); + + spin_unlock(&port->lock); + return IRQ_HANDLED; +} + +/* interrupt handler for s3c64xx and later SoC's.*/ +static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id) +{ + const struct s3c24xx_uart_port *ourport = id; + const struct uart_port *port = &ourport->port; + unsigned int pend = rd_regl(port, S3C64XX_UINTP); + irqreturn_t ret = IRQ_HANDLED; + + if (pend & S3C64XX_UINTM_RXD_MSK) { + ret = s3c24xx_serial_rx_irq(irq, id); + wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK); + } + if (pend & S3C64XX_UINTM_TXD_MSK) { + ret = s3c24xx_serial_tx_irq(irq, id); + wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK); + } + return ret; +} + +/* interrupt handler for Apple SoC's.*/ +static irqreturn_t apple_serial_handle_irq(int irq, void *id) +{ + const struct s3c24xx_uart_port *ourport = id; + const struct uart_port *port = &ourport->port; + unsigned int pend = rd_regl(port, S3C2410_UTRSTAT); + irqreturn_t ret = IRQ_NONE; + + if (pend & (APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO)) { + wr_regl(port, S3C2410_UTRSTAT, + APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO); + ret = s3c24xx_serial_rx_irq(irq, id); + } + if (pend & APPLE_S5L_UTRSTAT_TXTHRESH) { + wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_TXTHRESH); + ret = s3c24xx_serial_tx_irq(irq, id); + } + + return ret; +} + +static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT); + unsigned long ufcon = rd_regl(port, S3C2410_UFCON); + + if (ufcon & S3C2410_UFCON_FIFOMODE) { + if ((ufstat & info->tx_fifomask) != 0 || + (ufstat & info->tx_fifofull)) + return 0; + + return 1; + } + + return s3c24xx_serial_txempty_nofifo(port); +} + +/* no modem control lines */ +static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port) +{ + unsigned int umstat = rd_reg(port, S3C2410_UMSTAT); + + if (umstat & S3C2410_UMSTAT_CTS) + return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + else + return TIOCM_CAR | TIOCM_DSR; +} + +static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + unsigned int umcon = rd_regl(port, S3C2410_UMCON); + unsigned int ucon = rd_regl(port, S3C2410_UCON); + + if (mctrl & TIOCM_RTS) + umcon |= S3C2410_UMCOM_RTS_LOW; + else + umcon &= ~S3C2410_UMCOM_RTS_LOW; + + wr_regl(port, S3C2410_UMCON, umcon); + + if (mctrl & TIOCM_LOOP) + ucon |= S3C2410_UCON_LOOPBACK; + else + ucon &= ~S3C2410_UCON_LOOPBACK; + + wr_regl(port, S3C2410_UCON, ucon); +} + +static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state) +{ + unsigned long flags; + unsigned int ucon; + + spin_lock_irqsave(&port->lock, flags); + + ucon = rd_regl(port, S3C2410_UCON); + + if (break_state) + ucon |= S3C2410_UCON_SBREAK; + else + ucon &= ~S3C2410_UCON_SBREAK; + + wr_regl(port, S3C2410_UCON, ucon); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p) +{ + struct s3c24xx_uart_dma *dma = p->dma; + struct dma_slave_caps dma_caps; + const char *reason = NULL; + int ret; + + /* Default slave configuration parameters */ + dma->rx_conf.direction = DMA_DEV_TO_MEM; + dma->rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma->rx_conf.src_addr = p->port.mapbase + S3C2410_URXH; + dma->rx_conf.src_maxburst = 1; + + dma->tx_conf.direction = DMA_MEM_TO_DEV; + dma->tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma->tx_conf.dst_addr = p->port.mapbase + S3C2410_UTXH; + dma->tx_conf.dst_maxburst = 1; + + dma->rx_chan = dma_request_chan(p->port.dev, "rx"); + + if (IS_ERR(dma->rx_chan)) { + reason = "DMA RX channel request failed"; + ret = PTR_ERR(dma->rx_chan); + goto err_warn; + } + + ret = dma_get_slave_caps(dma->rx_chan, &dma_caps); + if (ret < 0 || + dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) { + reason = "insufficient DMA RX engine capabilities"; + ret = -EOPNOTSUPP; + goto err_release_rx; + } + + dmaengine_slave_config(dma->rx_chan, &dma->rx_conf); + + dma->tx_chan = dma_request_chan(p->port.dev, "tx"); + if (IS_ERR(dma->tx_chan)) { + reason = "DMA TX channel request failed"; + ret = PTR_ERR(dma->tx_chan); + goto err_release_rx; + } + + ret = dma_get_slave_caps(dma->tx_chan, &dma_caps); + if (ret < 0 || + dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) { + reason = "insufficient DMA TX engine capabilities"; + ret = -EOPNOTSUPP; + goto err_release_tx; + } + + dmaengine_slave_config(dma->tx_chan, &dma->tx_conf); + + /* RX buffer */ + dma->rx_size = PAGE_SIZE; + + dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL); + if (!dma->rx_buf) { + ret = -ENOMEM; + goto err_release_tx; + } + + dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf, + dma->rx_size, DMA_FROM_DEVICE); + if (dma_mapping_error(dma->rx_chan->device->dev, dma->rx_addr)) { + reason = "DMA mapping error for RX buffer"; + ret = -EIO; + goto err_free_rx; + } + + /* TX buffer */ + dma->tx_addr = dma_map_single(dma->tx_chan->device->dev, + p->port.state->xmit.buf, UART_XMIT_SIZE, + DMA_TO_DEVICE); + if (dma_mapping_error(dma->tx_chan->device->dev, dma->tx_addr)) { + reason = "DMA mapping error for TX buffer"; + ret = -EIO; + goto err_unmap_rx; + } + + return 0; + +err_unmap_rx: + dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); +err_free_rx: + kfree(dma->rx_buf); +err_release_tx: + dma_release_channel(dma->tx_chan); +err_release_rx: + dma_release_channel(dma->rx_chan); +err_warn: + if (reason) + dev_warn(p->port.dev, "%s, DMA will not be used\n", reason); + return ret; +} + +static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p) +{ + struct s3c24xx_uart_dma *dma = p->dma; + + if (dma->rx_chan) { + dmaengine_terminate_all(dma->rx_chan); + dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr, + dma->rx_size, DMA_FROM_DEVICE); + kfree(dma->rx_buf); + dma_release_channel(dma->rx_chan); + dma->rx_chan = NULL; + } + + if (dma->tx_chan) { + dmaengine_terminate_all(dma->tx_chan); + dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr, + UART_XMIT_SIZE, DMA_TO_DEVICE); + dma_release_channel(dma->tx_chan); + dma->tx_chan = NULL; + } +} + +static void s3c24xx_serial_shutdown(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + + if (ourport->tx_claimed) { + free_irq(ourport->tx_irq, ourport); + ourport->tx_enabled = 0; + ourport->tx_claimed = 0; + ourport->tx_mode = 0; + } + + if (ourport->rx_claimed) { + free_irq(ourport->rx_irq, ourport); + ourport->rx_claimed = 0; + ourport->rx_enabled = 0; + } + + if (ourport->dma) + s3c24xx_serial_release_dma(ourport); + + ourport->tx_in_progress = 0; +} + +static void s3c64xx_serial_shutdown(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + + ourport->tx_enabled = 0; + ourport->tx_mode = 0; + ourport->rx_enabled = 0; + + free_irq(port->irq, ourport); + + wr_regl(port, S3C64XX_UINTP, 0xf); + wr_regl(port, S3C64XX_UINTM, 0xf); + + if (ourport->dma) + s3c24xx_serial_release_dma(ourport); + + ourport->tx_in_progress = 0; +} + +static void apple_s5l_serial_shutdown(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + + unsigned int ucon; + + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTO_ENA_MSK); + wr_regl(port, S3C2410_UCON, ucon); + + wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS); + + free_irq(port->irq, ourport); + + ourport->tx_enabled = 0; + ourport->tx_mode = 0; + ourport->rx_enabled = 0; + + if (ourport->dma) + s3c24xx_serial_release_dma(ourport); + + ourport->tx_in_progress = 0; +} + +static int s3c24xx_serial_startup(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + int ret; + + ourport->rx_enabled = 1; + + ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_irq, 0, + s3c24xx_serial_portname(port), ourport); + + if (ret != 0) { + dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq); + return ret; + } + + ourport->rx_claimed = 1; + + dev_dbg(port->dev, "requesting tx irq...\n"); + + ourport->tx_enabled = 1; + + ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_irq, 0, + s3c24xx_serial_portname(port), ourport); + + if (ret) { + dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq); + goto err; + } + + ourport->tx_claimed = 1; + + /* the port reset code should have done the correct + * register setup for the port controls + */ + + return ret; + +err: + s3c24xx_serial_shutdown(port); + return ret; +} + +static int s3c64xx_serial_startup(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + unsigned long flags; + unsigned int ufcon; + int ret; + + wr_regl(port, S3C64XX_UINTM, 0xf); + if (ourport->dma) { + ret = s3c24xx_serial_request_dma(ourport); + if (ret < 0) { + devm_kfree(port->dev, ourport->dma); + ourport->dma = NULL; + } + } + + ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED, + s3c24xx_serial_portname(port), ourport); + if (ret) { + dev_err(port->dev, "cannot get irq %d\n", port->irq); + return ret; + } + + /* For compatibility with s3c24xx Soc's */ + ourport->rx_enabled = 1; + ourport->tx_enabled = 0; + + spin_lock_irqsave(&port->lock, flags); + + ufcon = rd_regl(port, S3C2410_UFCON); + ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8; + if (!uart_console(port)) + ufcon |= S3C2410_UFCON_RESETTX; + wr_regl(port, S3C2410_UFCON, ufcon); + + enable_rx_pio(ourport); + + spin_unlock_irqrestore(&port->lock, flags); + + /* Enable Rx Interrupt */ + s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM); + + return ret; +} + +static int apple_s5l_serial_startup(struct uart_port *port) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + unsigned long flags; + unsigned int ufcon; + int ret; + + wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS); + + ret = request_irq(port->irq, apple_serial_handle_irq, 0, + s3c24xx_serial_portname(port), ourport); + if (ret) { + dev_err(port->dev, "cannot get irq %d\n", port->irq); + return ret; + } + + /* For compatibility with s3c24xx Soc's */ + ourport->rx_enabled = 1; + ourport->tx_enabled = 0; + + spin_lock_irqsave(&port->lock, flags); + + ufcon = rd_regl(port, S3C2410_UFCON); + ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8; + if (!uart_console(port)) + ufcon |= S3C2410_UFCON_RESETTX; + wr_regl(port, S3C2410_UFCON, ufcon); + + enable_rx_pio(ourport); + + spin_unlock_irqrestore(&port->lock, flags); + + /* Enable Rx Interrupt */ + s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON); + s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON); + + return ret; +} + +/* power power management control */ + +static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level, + unsigned int old) +{ + struct s3c24xx_uart_port *ourport = to_ourport(port); + int timeout = 10000; + + ourport->pm_level = level; + + switch (level) { + case 3: + while (--timeout && !s3c24xx_serial_txempty_nofifo(port)) + udelay(100); + + if (!IS_ERR(ourport->baudclk)) + clk_disable_unprepare(ourport->baudclk); + + clk_disable_unprepare(ourport->clk); + break; + + case 0: + clk_prepare_enable(ourport->clk); + + if (!IS_ERR(ourport->baudclk)) + clk_prepare_enable(ourport->baudclk); + break; + default: + dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level); + } +} + +/* baud rate calculation + * + * The UARTs on the S3C2410/S3C2440 can take their clocks from a number + * of different sources, including the peripheral clock ("pclk") and an + * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk") + * with a programmable extra divisor. + * + * The following code goes through the clock sources, and calculates the + * baud clocks (and the resultant actual baud rates) and then tries to + * pick the closest one and select that. + * + */ + +#define MAX_CLK_NAME_LENGTH 15 + +static inline int s3c24xx_serial_getsource(struct uart_port *port) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + unsigned int ucon; + + if (info->num_clks == 1) + return 0; + + ucon = rd_regl(port, S3C2410_UCON); + ucon &= info->clksel_mask; + return ucon >> info->clksel_shift; +} + +static void s3c24xx_serial_setsource(struct uart_port *port, + unsigned int clk_sel) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + unsigned int ucon; + + if (info->num_clks == 1) + return; + + ucon = rd_regl(port, S3C2410_UCON); + if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel) + return; + + ucon &= ~info->clksel_mask; + ucon |= clk_sel << info->clksel_shift; + wr_regl(port, S3C2410_UCON, ucon); +} + +static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport, + unsigned int req_baud, struct clk **best_clk, + unsigned int *clk_num) +{ + const struct s3c24xx_uart_info *info = ourport->info; + struct clk *clk; + unsigned long rate; + unsigned int cnt, baud, quot, best_quot = 0; + char clkname[MAX_CLK_NAME_LENGTH]; + int calc_deviation, deviation = (1 << 30) - 1; + + for (cnt = 0; cnt < info->num_clks; cnt++) { + /* Keep selected clock if provided */ + if (ourport->cfg->clk_sel && + !(ourport->cfg->clk_sel & (1 << cnt))) + continue; + + sprintf(clkname, "clk_uart_baud%d", cnt); + clk = clk_get(ourport->port.dev, clkname); + if (IS_ERR(clk)) + continue; + + rate = clk_get_rate(clk); + if (!rate) { + dev_err(ourport->port.dev, + "Failed to get clock rate for %s.\n", clkname); + clk_put(clk); + continue; + } + + if (ourport->info->has_divslot) { + unsigned long div = rate / req_baud; + + /* The UDIVSLOT register on the newer UARTs allows us to + * get a divisor adjustment of 1/16th on the baud clock. + * + * We don't keep the UDIVSLOT value (the 16ths we + * calculated by not multiplying the baud by 16) as it + * is easy enough to recalculate. + */ + + quot = div / 16; + baud = rate / div; + } else { + quot = (rate + (8 * req_baud)) / (16 * req_baud); + baud = rate / (quot * 16); + } + quot--; + + calc_deviation = req_baud - baud; + if (calc_deviation < 0) + calc_deviation = -calc_deviation; + + if (calc_deviation < deviation) { + /* + * If we find a better clk, release the previous one, if + * any. + */ + if (!IS_ERR(*best_clk)) + clk_put(*best_clk); + *best_clk = clk; + best_quot = quot; + *clk_num = cnt; + deviation = calc_deviation; + } else { + clk_put(clk); + } + } + + return best_quot; +} + +/* udivslot_table[] + * + * This table takes the fractional value of the baud divisor and gives + * the recommended setting for the UDIVSLOT register. + */ +static const u16 udivslot_table[16] = { + [0] = 0x0000, + [1] = 0x0080, + [2] = 0x0808, + [3] = 0x0888, + [4] = 0x2222, + [5] = 0x4924, + [6] = 0x4A52, + [7] = 0x54AA, + [8] = 0x5555, + [9] = 0xD555, + [10] = 0xD5D5, + [11] = 0xDDD5, + [12] = 0xDDDD, + [13] = 0xDFDD, + [14] = 0xDFDF, + [15] = 0xFFDF, +}; + +static void s3c24xx_serial_set_termios(struct uart_port *port, + struct ktermios *termios, + const struct ktermios *old) +{ + const struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port); + struct s3c24xx_uart_port *ourport = to_ourport(port); + struct clk *clk = ERR_PTR(-EINVAL); + unsigned long flags; + unsigned int baud, quot, clk_sel = 0; + unsigned int ulcon; + unsigned int umcon; + unsigned int udivslot = 0; + + /* + * We don't support modem control lines. + */ + termios->c_cflag &= ~(HUPCL | CMSPAR); + termios->c_cflag |= CLOCAL; + + /* + * Ask the core to calculate the divisor for us. + */ + + baud = uart_get_baud_rate(port, termios, old, 0, 3000000); + quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel); + if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) + quot = port->custom_divisor; + if (IS_ERR(clk)) + return; + + /* check to see if we need to change clock source */ + + if (ourport->baudclk != clk) { + clk_prepare_enable(clk); + + s3c24xx_serial_setsource(port, clk_sel); + + if (!IS_ERR(ourport->baudclk)) { + clk_disable_unprepare(ourport->baudclk); + ourport->baudclk = ERR_PTR(-EINVAL); + } + + ourport->baudclk = clk; + ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0; + } + + if (ourport->info->has_divslot) { + unsigned int div = ourport->baudclk_rate / baud; + + if (cfg->has_fracval) { + udivslot = (div & 15); + dev_dbg(port->dev, "fracval = %04x\n", udivslot); + } else { + udivslot = udivslot_table[div & 15]; + dev_dbg(port->dev, "udivslot = %04x (div %d)\n", + udivslot, div & 15); + } + } + + switch (termios->c_cflag & CSIZE) { + case CS5: + dev_dbg(port->dev, "config: 5bits/char\n"); + ulcon = S3C2410_LCON_CS5; + break; + case CS6: + dev_dbg(port->dev, "config: 6bits/char\n"); + ulcon = S3C2410_LCON_CS6; + break; + case CS7: + dev_dbg(port->dev, "config: 7bits/char\n"); + ulcon = S3C2410_LCON_CS7; + break; + case CS8: + default: + dev_dbg(port->dev, "config: 8bits/char\n"); + ulcon = S3C2410_LCON_CS8; + break; + } + + /* preserve original lcon IR settings */ + ulcon |= (cfg->ulcon & S3C2410_LCON_IRM); + + if (termios->c_cflag & CSTOPB) + ulcon |= S3C2410_LCON_STOPB; + + if (termios->c_cflag & PARENB) { + if (termios->c_cflag & PARODD) + ulcon |= S3C2410_LCON_PODD; + else + ulcon |= S3C2410_LCON_PEVEN; + } else { + ulcon |= S3C2410_LCON_PNONE; + } + + spin_lock_irqsave(&port->lock, flags); + + dev_dbg(port->dev, + "setting ulcon to %08x, brddiv to %d, udivslot %08x\n", + ulcon, quot, udivslot); + + wr_regl(port, S3C2410_ULCON, ulcon); + wr_regl(port, S3C2410_UBRDIV, quot); + + port->status &= ~UPSTAT_AUTOCTS; + + umcon = rd_regl(port, S3C2410_UMCON); + if (termios->c_cflag & CRTSCTS) { + umcon |= S3C2410_UMCOM_AFC; + /* Disable RTS when RX FIFO contains 63 bytes */ + umcon &= ~S3C2412_UMCON_AFC_8; + port->status = UPSTAT_AUTOCTS; + } else { + umcon &= ~S3C2410_UMCOM_AFC; + } + wr_regl(port, S3C2410_UMCON, umcon); + + if (ourport->info->has_divslot) + wr_regl(port, S3C2443_DIVSLOT, udivslot); + + dev_dbg(port->dev, + "uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n", + rd_regl(port, S3C2410_ULCON), + rd_regl(port, S3C2410_UCON), + rd_regl(port, S3C2410_UFCON)); + + /* + * Update the per-port timeout. + */ + uart_update_timeout(port, termios->c_cflag, baud); + + /* + * Which character status flags are we interested in? + */ + port->read_status_mask = S3C2410_UERSTAT_OVERRUN; + if (termios->c_iflag & INPCK) + port->read_status_mask |= S3C2410_UERSTAT_FRAME | + S3C2410_UERSTAT_PARITY; + /* + * Which character status flags should we ignore? + */ + port->ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN; + if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR) + port->ignore_status_mask |= S3C2410_UERSTAT_FRAME; + + /* + * Ignore all characters if CREAD is not set. + */ + if ((termios->c_cflag & CREAD) == 0) + port->ignore_status_mask |= RXSTAT_DUMMY_READ; + + spin_unlock_irqrestore(&port->lock, flags); +} + +static const char *s3c24xx_serial_type(struct uart_port *port) +{ + const struct s3c24xx_uart_port *ourport = to_ourport(port); + + switch (ourport->info->type) { + case TYPE_S3C24XX: + return "S3C24XX"; + case TYPE_S3C6400: + return "S3C6400/10"; + case TYPE_APPLE_S5L: + return "APPLE S5L"; + default: + return NULL; + } +} + +static void s3c24xx_serial_config_port(struct uart_port *port, int flags) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + + if (flags & UART_CONFIG_TYPE) + port->type = info->port_type; +} + +/* + * verify the new serial_struct (for TIOCSSERIAL). + */ +static int +s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + + if (ser->type != PORT_UNKNOWN && ser->type != info->port_type) + return -EINVAL; + + return 0; +} + +#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE + +static struct console s3c24xx_serial_console; + +static void __init s3c24xx_serial_register_console(void) +{ + register_console(&s3c24xx_serial_console); +} + +static void s3c24xx_serial_unregister_console(void) +{ + if (s3c24xx_serial_console.flags & CON_ENABLED) + unregister_console(&s3c24xx_serial_console); +} + +#define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console +#else +static inline void s3c24xx_serial_register_console(void) { } +static inline void s3c24xx_serial_unregister_console(void) { } +#define S3C24XX_SERIAL_CONSOLE NULL +#endif + +#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL) +static int s3c24xx_serial_get_poll_char(struct uart_port *port); +static void s3c24xx_serial_put_poll_char(struct uart_port *port, + unsigned char c); +#endif + +static const struct uart_ops s3c24xx_serial_ops = { + .pm = s3c24xx_serial_pm, + .tx_empty = s3c24xx_serial_tx_empty, + .get_mctrl = s3c24xx_serial_get_mctrl, + .set_mctrl = s3c24xx_serial_set_mctrl, + .stop_tx = s3c24xx_serial_stop_tx, + .start_tx = s3c24xx_serial_start_tx, + .stop_rx = s3c24xx_serial_stop_rx, + .break_ctl = s3c24xx_serial_break_ctl, + .startup = s3c24xx_serial_startup, + .shutdown = s3c24xx_serial_shutdown, + .set_termios = s3c24xx_serial_set_termios, + .type = s3c24xx_serial_type, + .config_port = s3c24xx_serial_config_port, + .verify_port = s3c24xx_serial_verify_port, +#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL) + .poll_get_char = s3c24xx_serial_get_poll_char, + .poll_put_char = s3c24xx_serial_put_poll_char, +#endif +}; + +static const struct uart_ops s3c64xx_serial_ops = { + .pm = s3c24xx_serial_pm, + .tx_empty = s3c24xx_serial_tx_empty, + .get_mctrl = s3c24xx_serial_get_mctrl, + .set_mctrl = s3c24xx_serial_set_mctrl, + .stop_tx = s3c24xx_serial_stop_tx, + .start_tx = s3c24xx_serial_start_tx, + .stop_rx = s3c24xx_serial_stop_rx, + .break_ctl = s3c24xx_serial_break_ctl, + .startup = s3c64xx_serial_startup, + .shutdown = s3c64xx_serial_shutdown, + .set_termios = s3c24xx_serial_set_termios, + .type = s3c24xx_serial_type, + .config_port = s3c24xx_serial_config_port, + .verify_port = s3c24xx_serial_verify_port, +#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL) + .poll_get_char = s3c24xx_serial_get_poll_char, + .poll_put_char = s3c24xx_serial_put_poll_char, +#endif +}; + +static const struct uart_ops apple_s5l_serial_ops = { + .pm = s3c24xx_serial_pm, + .tx_empty = s3c24xx_serial_tx_empty, + .get_mctrl = s3c24xx_serial_get_mctrl, + .set_mctrl = s3c24xx_serial_set_mctrl, + .stop_tx = s3c24xx_serial_stop_tx, + .start_tx = s3c24xx_serial_start_tx, + .stop_rx = s3c24xx_serial_stop_rx, + .break_ctl = s3c24xx_serial_break_ctl, + .startup = apple_s5l_serial_startup, + .shutdown = apple_s5l_serial_shutdown, + .set_termios = s3c24xx_serial_set_termios, + .type = s3c24xx_serial_type, + .config_port = s3c24xx_serial_config_port, + .verify_port = s3c24xx_serial_verify_port, +#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL) + .poll_get_char = s3c24xx_serial_get_poll_char, + .poll_put_char = s3c24xx_serial_put_poll_char, +#endif +}; + +static struct uart_driver s3c24xx_uart_drv = { + .owner = THIS_MODULE, + .driver_name = "s3c2410_serial", + .nr = UART_NR, + .cons = S3C24XX_SERIAL_CONSOLE, + .dev_name = S3C24XX_SERIAL_NAME, + .major = S3C24XX_SERIAL_MAJOR, + .minor = S3C24XX_SERIAL_MINOR, +}; + +static struct s3c24xx_uart_port s3c24xx_serial_ports[UART_NR]; + +static void s3c24xx_serial_init_port_default(int index) { + struct uart_port *port = &s3c24xx_serial_ports[index].port; + + spin_lock_init(&port->lock); + + port->iotype = UPIO_MEM; + port->uartclk = 0; + port->fifosize = 16; + port->ops = &s3c24xx_serial_ops; + port->flags = UPF_BOOT_AUTOCONF; + port->line = index; +} + +/* s3c24xx_serial_resetport + * + * reset the fifos and other the settings. + */ + +static void s3c24xx_serial_resetport(struct uart_port *port, + const struct s3c2410_uartcfg *cfg) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + unsigned long ucon = rd_regl(port, S3C2410_UCON); + + ucon &= (info->clksel_mask | info->ucon_mask); + wr_regl(port, S3C2410_UCON, ucon | cfg->ucon); + + /* reset both fifos */ + wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH); + wr_regl(port, S3C2410_UFCON, cfg->ufcon); + + /* some delay is required after fifo reset */ + udelay(1); +} + +#ifdef CONFIG_ARM_S3C24XX_CPUFREQ + +static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct s3c24xx_uart_port *port; + struct uart_port *uport; + + port = container_of(nb, struct s3c24xx_uart_port, freq_transition); + uport = &port->port; + + /* check to see if port is enabled */ + + if (port->pm_level != 0) + return 0; + + /* try and work out if the baudrate is changing, we can detect + * a change in rate, but we do not have support for detecting + * a disturbance in the clock-rate over the change. + */ + + if (IS_ERR(port->baudclk)) + goto exit; + + if (port->baudclk_rate == clk_get_rate(port->baudclk)) + goto exit; + + if (val == CPUFREQ_PRECHANGE) { + /* we should really shut the port down whilst the + * frequency change is in progress. + */ + + } else if (val == CPUFREQ_POSTCHANGE) { + struct ktermios *termios; + struct tty_struct *tty; + + if (uport->state == NULL) + goto exit; + + tty = uport->state->port.tty; + + if (tty == NULL) + goto exit; + + termios = &tty->termios; + + if (termios == NULL) { + dev_warn(uport->dev, "%s: no termios?\n", __func__); + goto exit; + } + + s3c24xx_serial_set_termios(uport, termios, NULL); + } + +exit: + return 0; +} + +static inline int +s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port) +{ + port->freq_transition.notifier_call = s3c24xx_serial_cpufreq_transition; + + return cpufreq_register_notifier(&port->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} + +static inline void +s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port) +{ + cpufreq_unregister_notifier(&port->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} + +#else +static inline int +s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port) +{ + return 0; +} + +static inline void +s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port) +{ +} +#endif + +static int s3c24xx_serial_enable_baudclk(struct s3c24xx_uart_port *ourport) +{ + struct device *dev = ourport->port.dev; + const struct s3c24xx_uart_info *info = ourport->info; + char clk_name[MAX_CLK_NAME_LENGTH]; + unsigned int clk_sel; + struct clk *clk; + int clk_num; + int ret; + + clk_sel = ourport->cfg->clk_sel ? : info->def_clk_sel; + for (clk_num = 0; clk_num < info->num_clks; clk_num++) { + if (!(clk_sel & (1 << clk_num))) + continue; + + sprintf(clk_name, "clk_uart_baud%d", clk_num); + clk = clk_get(dev, clk_name); + if (IS_ERR(clk)) + continue; + + ret = clk_prepare_enable(clk); + if (ret) { + clk_put(clk); + continue; + } + + ourport->baudclk = clk; + ourport->baudclk_rate = clk_get_rate(clk); + s3c24xx_serial_setsource(&ourport->port, clk_num); + + return 0; + } + + return -EINVAL; +} + +/* s3c24xx_serial_init_port + * + * initialise a single serial port from the platform device given + */ + +static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport, + struct platform_device *platdev) +{ + struct uart_port *port = &ourport->port; + const struct s3c2410_uartcfg *cfg = ourport->cfg; + struct resource *res; + int ret; + + if (platdev == NULL) + return -ENODEV; + + if (port->mapbase != 0) + return -EINVAL; + + /* setup info for port */ + port->dev = &platdev->dev; + + port->uartclk = 1; + + if (cfg->uart_flags & UPF_CONS_FLOW) { + dev_dbg(port->dev, "enabling flow control\n"); + port->flags |= UPF_CONS_FLOW; + } + + /* sort our the physical and virtual addresses for each UART */ + + res = platform_get_resource(platdev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(port->dev, "failed to find memory resource for uart\n"); + return -EINVAL; + } + + dev_dbg(port->dev, "resource %pR)\n", res); + + port->membase = devm_ioremap_resource(port->dev, res); + if (IS_ERR(port->membase)) { + dev_err(port->dev, "failed to remap controller address\n"); + return -EBUSY; + } + + port->mapbase = res->start; + ret = platform_get_irq(platdev, 0); + if (ret < 0) { + port->irq = 0; + } else { + port->irq = ret; + ourport->rx_irq = ret; + ourport->tx_irq = ret + 1; + } + + switch (ourport->info->type) { + case TYPE_S3C24XX: + ret = platform_get_irq(platdev, 1); + if (ret > 0) + ourport->tx_irq = ret; + break; + default: + break; + } + + /* + * DMA is currently supported only on DT platforms, if DMA properties + * are specified. + */ + if (platdev->dev.of_node && of_find_property(platdev->dev.of_node, + "dmas", NULL)) { + ourport->dma = devm_kzalloc(port->dev, + sizeof(*ourport->dma), + GFP_KERNEL); + if (!ourport->dma) { + ret = -ENOMEM; + goto err; + } + } + + ourport->clk = clk_get(&platdev->dev, "uart"); + if (IS_ERR(ourport->clk)) { + pr_err("%s: Controller clock not found\n", + dev_name(&platdev->dev)); + ret = PTR_ERR(ourport->clk); + goto err; + } + + ret = clk_prepare_enable(ourport->clk); + if (ret) { + pr_err("uart: clock failed to prepare+enable: %d\n", ret); + clk_put(ourport->clk); + goto err; + } + + ret = s3c24xx_serial_enable_baudclk(ourport); + if (ret) + pr_warn("uart: failed to enable baudclk\n"); + + /* Keep all interrupts masked and cleared */ + switch (ourport->info->type) { + case TYPE_S3C6400: + wr_regl(port, S3C64XX_UINTM, 0xf); + wr_regl(port, S3C64XX_UINTP, 0xf); + wr_regl(port, S3C64XX_UINTSP, 0xf); + break; + case TYPE_APPLE_S5L: { + unsigned int ucon; + + ucon = rd_regl(port, S3C2410_UCON); + ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTO_ENA_MSK); + wr_regl(port, S3C2410_UCON, ucon); + + wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS); + break; + } + default: + break; + } + + dev_dbg(port->dev, "port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n", + &port->mapbase, port->membase, port->irq, + ourport->rx_irq, ourport->tx_irq, port->uartclk); + + /* reset the fifos (and setup the uart) */ + s3c24xx_serial_resetport(port, cfg); + + return 0; + +err: + port->mapbase = 0; + return ret; +} + +/* Device driver serial port probe */ + +static int probe_index; + +static inline const struct s3c24xx_serial_drv_data * +s3c24xx_get_driver_data(struct platform_device *pdev) +{ + if (dev_of_node(&pdev->dev)) + return of_device_get_match_data(&pdev->dev); + + return (struct s3c24xx_serial_drv_data *) + platform_get_device_id(pdev)->driver_data; +} + +static int s3c24xx_serial_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct s3c24xx_uart_port *ourport; + int index = probe_index; + int ret, prop = 0; + + if (np) { + ret = of_alias_get_id(np, "serial"); + if (ret >= 0) + index = ret; + } + + if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) { + dev_err(&pdev->dev, "serial%d out of range\n", index); + return -EINVAL; + } + ourport = &s3c24xx_serial_ports[index]; + + s3c24xx_serial_init_port_default(index); + + ourport->drv_data = s3c24xx_get_driver_data(pdev); + if (!ourport->drv_data) { + dev_err(&pdev->dev, "could not find driver data\n"); + return -ENODEV; + } + + ourport->baudclk = ERR_PTR(-EINVAL); + ourport->info = &ourport->drv_data->info; + ourport->cfg = (dev_get_platdata(&pdev->dev)) ? + dev_get_platdata(&pdev->dev) : + &ourport->drv_data->def_cfg; + + switch (ourport->info->type) { + case TYPE_S3C24XX: + ourport->port.ops = &s3c24xx_serial_ops; + break; + case TYPE_S3C6400: + ourport->port.ops = &s3c64xx_serial_ops; + break; + case TYPE_APPLE_S5L: + ourport->port.ops = &apple_s5l_serial_ops; + break; + } + + if (np) { + of_property_read_u32(np, + "samsung,uart-fifosize", &ourport->port.fifosize); + + if (of_property_read_u32(np, "reg-io-width", &prop) == 0) { + switch (prop) { + case 1: + ourport->port.iotype = UPIO_MEM; + break; + case 4: + ourport->port.iotype = UPIO_MEM32; + break; + default: + dev_warn(&pdev->dev, "unsupported reg-io-width (%d)\n", + prop); + return -EINVAL; + } + } + } + + if (ourport->drv_data->fifosize[index]) + ourport->port.fifosize = ourport->drv_data->fifosize[index]; + else if (ourport->info->fifosize) + ourport->port.fifosize = ourport->info->fifosize; + ourport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SAMSUNG_CONSOLE); + + /* + * DMA transfers must be aligned at least to cache line size, + * so find minimal transfer size suitable for DMA mode + */ + ourport->min_dma_size = max_t(int, ourport->port.fifosize, + dma_get_cache_alignment()); + + dev_dbg(&pdev->dev, "%s: initialising port %p...\n", __func__, ourport); + + ret = s3c24xx_serial_init_port(ourport, pdev); + if (ret < 0) + return ret; + + if (!s3c24xx_uart_drv.state) { + ret = uart_register_driver(&s3c24xx_uart_drv); + if (ret < 0) { + pr_err("Failed to register Samsung UART driver\n"); + return ret; + } + } + + dev_dbg(&pdev->dev, "%s: adding port\n", __func__); + uart_add_one_port(&s3c24xx_uart_drv, &ourport->port); + platform_set_drvdata(pdev, &ourport->port); + + /* + * Deactivate the clock enabled in s3c24xx_serial_init_port here, + * so that a potential re-enablement through the pm-callback overlaps + * and keeps the clock enabled in this case. + */ + clk_disable_unprepare(ourport->clk); + if (!IS_ERR(ourport->baudclk)) + clk_disable_unprepare(ourport->baudclk); + + ret = s3c24xx_serial_cpufreq_register(ourport); + if (ret < 0) + dev_err(&pdev->dev, "failed to add cpufreq notifier\n"); + + probe_index++; + + return 0; +} + +static int s3c24xx_serial_remove(struct platform_device *dev) +{ + struct uart_port *port = s3c24xx_dev_to_port(&dev->dev); + + if (port) { + s3c24xx_serial_cpufreq_deregister(to_ourport(port)); + uart_remove_one_port(&s3c24xx_uart_drv, port); + } + + uart_unregister_driver(&s3c24xx_uart_drv); + + return 0; +} + +/* UART power management code */ +#ifdef CONFIG_PM_SLEEP +static int s3c24xx_serial_suspend(struct device *dev) +{ + struct uart_port *port = s3c24xx_dev_to_port(dev); + + if (port) + uart_suspend_port(&s3c24xx_uart_drv, port); + + return 0; +} + +static int s3c24xx_serial_resume(struct device *dev) +{ + struct uart_port *port = s3c24xx_dev_to_port(dev); + struct s3c24xx_uart_port *ourport = to_ourport(port); + + if (port) { + clk_prepare_enable(ourport->clk); + if (!IS_ERR(ourport->baudclk)) + clk_prepare_enable(ourport->baudclk); + s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port)); + if (!IS_ERR(ourport->baudclk)) + clk_disable_unprepare(ourport->baudclk); + clk_disable_unprepare(ourport->clk); + + uart_resume_port(&s3c24xx_uart_drv, port); + } + + return 0; +} + +static int s3c24xx_serial_resume_noirq(struct device *dev) +{ + struct uart_port *port = s3c24xx_dev_to_port(dev); + struct s3c24xx_uart_port *ourport = to_ourport(port); + + if (port) { + /* restore IRQ mask */ + switch (ourport->info->type) { + case TYPE_S3C6400: { + unsigned int uintm = 0xf; + + if (ourport->tx_enabled) + uintm &= ~S3C64XX_UINTM_TXD_MSK; + if (ourport->rx_enabled) + uintm &= ~S3C64XX_UINTM_RXD_MSK; + clk_prepare_enable(ourport->clk); + if (!IS_ERR(ourport->baudclk)) + clk_prepare_enable(ourport->baudclk); + wr_regl(port, S3C64XX_UINTM, uintm); + if (!IS_ERR(ourport->baudclk)) + clk_disable_unprepare(ourport->baudclk); + clk_disable_unprepare(ourport->clk); + break; + } + case TYPE_APPLE_S5L: { + unsigned int ucon; + int ret; + + ret = clk_prepare_enable(ourport->clk); + if (ret) { + dev_err(dev, "clk_enable clk failed: %d\n", ret); + return ret; + } + if (!IS_ERR(ourport->baudclk)) { + ret = clk_prepare_enable(ourport->baudclk); + if (ret) { + dev_err(dev, "clk_enable baudclk failed: %d\n", ret); + clk_disable_unprepare(ourport->clk); + return ret; + } + } + + ucon = rd_regl(port, S3C2410_UCON); + + ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTO_ENA_MSK); + + if (ourport->tx_enabled) + ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK; + if (ourport->rx_enabled) + ucon |= APPLE_S5L_UCON_RXTHRESH_ENA_MSK | + APPLE_S5L_UCON_RXTO_ENA_MSK; + + wr_regl(port, S3C2410_UCON, ucon); + + if (!IS_ERR(ourport->baudclk)) + clk_disable_unprepare(ourport->baudclk); + clk_disable_unprepare(ourport->clk); + break; + } + default: + break; + } + } + + return 0; +} + +static const struct dev_pm_ops s3c24xx_serial_pm_ops = { + .suspend = s3c24xx_serial_suspend, + .resume = s3c24xx_serial_resume, + .resume_noirq = s3c24xx_serial_resume_noirq, +}; +#define SERIAL_SAMSUNG_PM_OPS (&s3c24xx_serial_pm_ops) + +#else /* !CONFIG_PM_SLEEP */ + +#define SERIAL_SAMSUNG_PM_OPS NULL +#endif /* CONFIG_PM_SLEEP */ + +/* Console code */ + +#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE + +static struct uart_port *cons_uart; + +static int +s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon) +{ + const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port); + unsigned long ufstat, utrstat; + + if (ufcon & S3C2410_UFCON_FIFOMODE) { + /* fifo mode - check amount of data in fifo registers... */ + + ufstat = rd_regl(port, S3C2410_UFSTAT); + return (ufstat & info->tx_fifofull) ? 0 : 1; + } + + /* in non-fifo mode, we go and use the tx buffer empty */ + + utrstat = rd_regl(port, S3C2410_UTRSTAT); + return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0; +} + +static bool +s3c24xx_port_configured(unsigned int ucon) +{ + /* consider the serial port configured if the tx/rx mode set */ + return (ucon & 0xf) != 0; +} + +#ifdef CONFIG_CONSOLE_POLL +/* + * Console polling routines for writing and reading from the uart while + * in an interrupt or debug context. + */ + +static int s3c24xx_serial_get_poll_char(struct uart_port *port) +{ + const struct s3c24xx_uart_port *ourport = to_ourport(port); + unsigned int ufstat; + + ufstat = rd_regl(port, S3C2410_UFSTAT); + if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0) + return NO_POLL_CHAR; + + return rd_reg(port, S3C2410_URXH); +} + +static void s3c24xx_serial_put_poll_char(struct uart_port *port, + unsigned char c) +{ + unsigned int ufcon = rd_regl(port, S3C2410_UFCON); + unsigned int ucon = rd_regl(port, S3C2410_UCON); + + /* not possible to xmit on unconfigured port */ + if (!s3c24xx_port_configured(ucon)) + return; + + while (!s3c24xx_serial_console_txrdy(port, ufcon)) + cpu_relax(); + wr_reg(port, S3C2410_UTXH, c); +} + +#endif /* CONFIG_CONSOLE_POLL */ + +static void +s3c24xx_serial_console_putchar(struct uart_port *port, unsigned char ch) +{ + unsigned int ufcon = rd_regl(port, S3C2410_UFCON); + + while (!s3c24xx_serial_console_txrdy(port, ufcon)) + cpu_relax(); + wr_reg(port, S3C2410_UTXH, ch); +} + +static void +s3c24xx_serial_console_write(struct console *co, const char *s, + unsigned int count) +{ + unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON); + unsigned long flags; + bool locked = true; + + /* not possible to xmit on unconfigured port */ + if (!s3c24xx_port_configured(ucon)) + return; + + if (cons_uart->sysrq) + locked = false; + else if (oops_in_progress) + locked = spin_trylock_irqsave(&cons_uart->lock, flags); + else + spin_lock_irqsave(&cons_uart->lock, flags); + + uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar); + + if (locked) + spin_unlock_irqrestore(&cons_uart->lock, flags); +} + +/* Shouldn't be __init, as it can be instantiated from other module */ +static void +s3c24xx_serial_get_options(struct uart_port *port, int *baud, + int *parity, int *bits) +{ + struct clk *clk; + unsigned int ulcon; + unsigned int ucon; + unsigned int ubrdiv; + unsigned long rate; + unsigned int clk_sel; + char clk_name[MAX_CLK_NAME_LENGTH]; + + ulcon = rd_regl(port, S3C2410_ULCON); + ucon = rd_regl(port, S3C2410_UCON); + ubrdiv = rd_regl(port, S3C2410_UBRDIV); + + if (s3c24xx_port_configured(ucon)) { + switch (ulcon & S3C2410_LCON_CSMASK) { + case S3C2410_LCON_CS5: + *bits = 5; + break; + case S3C2410_LCON_CS6: + *bits = 6; + break; + case S3C2410_LCON_CS7: + *bits = 7; + break; + case S3C2410_LCON_CS8: + default: + *bits = 8; + break; + } + + switch (ulcon & S3C2410_LCON_PMASK) { + case S3C2410_LCON_PEVEN: + *parity = 'e'; + break; + + case S3C2410_LCON_PODD: + *parity = 'o'; + break; + + case S3C2410_LCON_PNONE: + default: + *parity = 'n'; + } + + /* now calculate the baud rate */ + + clk_sel = s3c24xx_serial_getsource(port); + sprintf(clk_name, "clk_uart_baud%d", clk_sel); + + clk = clk_get(port->dev, clk_name); + if (!IS_ERR(clk)) + rate = clk_get_rate(clk); + else + rate = 1; + + *baud = rate / (16 * (ubrdiv + 1)); + dev_dbg(port->dev, "calculated baud %d\n", *baud); + } +} + +/* Shouldn't be __init, as it can be instantiated from other module */ +static int +s3c24xx_serial_console_setup(struct console *co, char *options) +{ + struct uart_port *port; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + /* is this a valid port */ + + if (co->index == -1 || co->index >= UART_NR) + co->index = 0; + + port = &s3c24xx_serial_ports[co->index].port; + + /* is the port configured? */ + + if (port->mapbase == 0x0) + return -ENODEV; + + cons_uart = port; + + /* + * Check whether an invalid uart number has been specified, and + * if so, search for the first available port that does have + * console support. + */ + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + else + s3c24xx_serial_get_options(port, &baud, &parity, &bits); + + dev_dbg(port->dev, "baud %d\n", baud); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct console s3c24xx_serial_console = { + .name = S3C24XX_SERIAL_NAME, + .device = uart_console_device, + .flags = CON_PRINTBUFFER, + .index = -1, + .write = s3c24xx_serial_console_write, + .setup = s3c24xx_serial_console_setup, + .data = &s3c24xx_uart_drv, +}; +#endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */ + +#ifdef CONFIG_CPU_S3C2410 +static const struct s3c24xx_serial_drv_data s3c2410_serial_drv_data = { + .info = { + .name = "Samsung S3C2410 UART", + .type = TYPE_S3C24XX, + .port_type = PORT_S3C2410, + .fifosize = 16, + .rx_fifomask = S3C2410_UFSTAT_RXMASK, + .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT, + .rx_fifofull = S3C2410_UFSTAT_RXFULL, + .tx_fifofull = S3C2410_UFSTAT_TXFULL, + .tx_fifomask = S3C2410_UFSTAT_TXMASK, + .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL0, + .num_clks = 2, + .clksel_mask = S3C2410_UCON_CLKMASK, + .clksel_shift = S3C2410_UCON_CLKSHIFT, + }, + .def_cfg = { + .ucon = S3C2410_UCON_DEFAULT, + .ufcon = S3C2410_UFCON_DEFAULT, + }, +}; +#define S3C2410_SERIAL_DRV_DATA (&s3c2410_serial_drv_data) +#else +#define S3C2410_SERIAL_DRV_DATA NULL +#endif + +#ifdef CONFIG_CPU_S3C2412 +static const struct s3c24xx_serial_drv_data s3c2412_serial_drv_data = { + .info = { + .name = "Samsung S3C2412 UART", + .type = TYPE_S3C24XX, + .port_type = PORT_S3C2412, + .fifosize = 64, + .has_divslot = 1, + .rx_fifomask = S3C2440_UFSTAT_RXMASK, + .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT, + .rx_fifofull = S3C2440_UFSTAT_RXFULL, + .tx_fifofull = S3C2440_UFSTAT_TXFULL, + .tx_fifomask = S3C2440_UFSTAT_TXMASK, + .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL2, + .num_clks = 4, + .clksel_mask = S3C2412_UCON_CLKMASK, + .clksel_shift = S3C2412_UCON_CLKSHIFT, + }, + .def_cfg = { + .ucon = S3C2410_UCON_DEFAULT, + .ufcon = S3C2410_UFCON_DEFAULT, + }, +}; +#define S3C2412_SERIAL_DRV_DATA (&s3c2412_serial_drv_data) +#else +#define S3C2412_SERIAL_DRV_DATA NULL +#endif + +#if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2416) || \ + defined(CONFIG_CPU_S3C2443) || defined(CONFIG_CPU_S3C2442) +static const struct s3c24xx_serial_drv_data s3c2440_serial_drv_data = { + .info = { + .name = "Samsung S3C2440 UART", + .type = TYPE_S3C24XX, + .port_type = PORT_S3C2440, + .fifosize = 64, + .has_divslot = 1, + .rx_fifomask = S3C2440_UFSTAT_RXMASK, + .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT, + .rx_fifofull = S3C2440_UFSTAT_RXFULL, + .tx_fifofull = S3C2440_UFSTAT_TXFULL, + .tx_fifomask = S3C2440_UFSTAT_TXMASK, + .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL2, + .num_clks = 4, + .clksel_mask = S3C2412_UCON_CLKMASK, + .clksel_shift = S3C2412_UCON_CLKSHIFT, + .ucon_mask = S3C2440_UCON0_DIVMASK, + }, + .def_cfg = { + .ucon = S3C2410_UCON_DEFAULT, + .ufcon = S3C2410_UFCON_DEFAULT, + }, +}; +#define S3C2440_SERIAL_DRV_DATA (&s3c2440_serial_drv_data) +#else +#define S3C2440_SERIAL_DRV_DATA NULL +#endif + +#if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410) +static const struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = { + .info = { + .name = "Samsung S3C6400 UART", + .type = TYPE_S3C6400, + .port_type = PORT_S3C6400, + .fifosize = 64, + .has_divslot = 1, + .rx_fifomask = S3C2440_UFSTAT_RXMASK, + .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT, + .rx_fifofull = S3C2440_UFSTAT_RXFULL, + .tx_fifofull = S3C2440_UFSTAT_TXFULL, + .tx_fifomask = S3C2440_UFSTAT_TXMASK, + .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL2, + .num_clks = 4, + .clksel_mask = S3C6400_UCON_CLKMASK, + .clksel_shift = S3C6400_UCON_CLKSHIFT, + }, + .def_cfg = { + .ucon = S3C2410_UCON_DEFAULT, + .ufcon = S3C2410_UFCON_DEFAULT, + }, +}; +#define S3C6400_SERIAL_DRV_DATA (&s3c6400_serial_drv_data) +#else +#define S3C6400_SERIAL_DRV_DATA NULL +#endif + +#ifdef CONFIG_CPU_S5PV210 +static const struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = { + .info = { + .name = "Samsung S5PV210 UART", + .type = TYPE_S3C6400, + .port_type = PORT_S3C6400, + .has_divslot = 1, + .rx_fifomask = S5PV210_UFSTAT_RXMASK, + .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, + .rx_fifofull = S5PV210_UFSTAT_RXFULL, + .tx_fifofull = S5PV210_UFSTAT_TXFULL, + .tx_fifomask = S5PV210_UFSTAT_TXMASK, + .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL0, + .num_clks = 2, + .clksel_mask = S5PV210_UCON_CLKMASK, + .clksel_shift = S5PV210_UCON_CLKSHIFT, + }, + .def_cfg = { + .ucon = S5PV210_UCON_DEFAULT, + .ufcon = S5PV210_UFCON_DEFAULT, + }, + .fifosize = { 256, 64, 16, 16 }, +}; +#define S5PV210_SERIAL_DRV_DATA (&s5pv210_serial_drv_data) +#else +#define S5PV210_SERIAL_DRV_DATA NULL +#endif + +#if defined(CONFIG_ARCH_EXYNOS) +#define EXYNOS_COMMON_SERIAL_DRV_DATA() \ + .info = { \ + .name = "Samsung Exynos UART", \ + .type = TYPE_S3C6400, \ + .port_type = PORT_S3C6400, \ + .has_divslot = 1, \ + .rx_fifomask = S5PV210_UFSTAT_RXMASK, \ + .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, \ + .rx_fifofull = S5PV210_UFSTAT_RXFULL, \ + .tx_fifofull = S5PV210_UFSTAT_TXFULL, \ + .tx_fifomask = S5PV210_UFSTAT_TXMASK, \ + .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, \ + .def_clk_sel = S3C2410_UCON_CLKSEL0, \ + .num_clks = 1, \ + .clksel_mask = 0, \ + .clksel_shift = 0, \ + }, \ + .def_cfg = { \ + .ucon = S5PV210_UCON_DEFAULT, \ + .ufcon = S5PV210_UFCON_DEFAULT, \ + .has_fracval = 1, \ + } \ + +static const struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = { + EXYNOS_COMMON_SERIAL_DRV_DATA(), + .fifosize = { 256, 64, 16, 16 }, +}; + +static const struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = { + EXYNOS_COMMON_SERIAL_DRV_DATA(), + .fifosize = { 64, 256, 16, 256 }, +}; + +static const struct s3c24xx_serial_drv_data exynos850_serial_drv_data = { + EXYNOS_COMMON_SERIAL_DRV_DATA(), + .fifosize = { 256, 64, 64, 64 }, +}; + +#define EXYNOS4210_SERIAL_DRV_DATA (&exynos4210_serial_drv_data) +#define EXYNOS5433_SERIAL_DRV_DATA (&exynos5433_serial_drv_data) +#define EXYNOS850_SERIAL_DRV_DATA (&exynos850_serial_drv_data) + +#else +#define EXYNOS4210_SERIAL_DRV_DATA NULL +#define EXYNOS5433_SERIAL_DRV_DATA NULL +#define EXYNOS850_SERIAL_DRV_DATA NULL +#endif + +#ifdef CONFIG_ARCH_APPLE +static const struct s3c24xx_serial_drv_data s5l_serial_drv_data = { + .info = { + .name = "Apple S5L UART", + .type = TYPE_APPLE_S5L, + .port_type = PORT_8250, + .fifosize = 16, + .rx_fifomask = S3C2410_UFSTAT_RXMASK, + .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT, + .rx_fifofull = S3C2410_UFSTAT_RXFULL, + .tx_fifofull = S3C2410_UFSTAT_TXFULL, + .tx_fifomask = S3C2410_UFSTAT_TXMASK, + .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL0, + .num_clks = 1, + .clksel_mask = 0, + .clksel_shift = 0, + .ucon_mask = APPLE_S5L_UCON_MASK, + }, + .def_cfg = { + .ucon = APPLE_S5L_UCON_DEFAULT, + .ufcon = S3C2410_UFCON_DEFAULT, + }, +}; +#define S5L_SERIAL_DRV_DATA (&s5l_serial_drv_data) +#else +#define S5L_SERIAL_DRV_DATA NULL +#endif + +#if defined(CONFIG_ARCH_ARTPEC) +static const struct s3c24xx_serial_drv_data artpec8_serial_drv_data = { + .info = { + .name = "Axis ARTPEC-8 UART", + .type = TYPE_S3C6400, + .port_type = PORT_S3C6400, + .fifosize = 64, + .has_divslot = 1, + .rx_fifomask = S5PV210_UFSTAT_RXMASK, + .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, + .rx_fifofull = S5PV210_UFSTAT_RXFULL, + .tx_fifofull = S5PV210_UFSTAT_TXFULL, + .tx_fifomask = S5PV210_UFSTAT_TXMASK, + .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, + .def_clk_sel = S3C2410_UCON_CLKSEL0, + .num_clks = 1, + .clksel_mask = 0, + .clksel_shift = 0, + }, + .def_cfg = { + .ucon = S5PV210_UCON_DEFAULT, + .ufcon = S5PV210_UFCON_DEFAULT, + .has_fracval = 1, + } +}; +#define ARTPEC8_SERIAL_DRV_DATA (&artpec8_serial_drv_data) +#else +#define ARTPEC8_SERIAL_DRV_DATA (NULL) +#endif + +static const struct platform_device_id s3c24xx_serial_driver_ids[] = { + { + .name = "s3c2410-uart", + .driver_data = (kernel_ulong_t)S3C2410_SERIAL_DRV_DATA, + }, { + .name = "s3c2412-uart", + .driver_data = (kernel_ulong_t)S3C2412_SERIAL_DRV_DATA, + }, { + .name = "s3c2440-uart", + .driver_data = (kernel_ulong_t)S3C2440_SERIAL_DRV_DATA, + }, { + .name = "s3c6400-uart", + .driver_data = (kernel_ulong_t)S3C6400_SERIAL_DRV_DATA, + }, { + .name = "s5pv210-uart", + .driver_data = (kernel_ulong_t)S5PV210_SERIAL_DRV_DATA, + }, { + .name = "exynos4210-uart", + .driver_data = (kernel_ulong_t)EXYNOS4210_SERIAL_DRV_DATA, + }, { + .name = "exynos5433-uart", + .driver_data = (kernel_ulong_t)EXYNOS5433_SERIAL_DRV_DATA, + }, { + .name = "s5l-uart", + .driver_data = (kernel_ulong_t)S5L_SERIAL_DRV_DATA, + }, { + .name = "exynos850-uart", + .driver_data = (kernel_ulong_t)EXYNOS850_SERIAL_DRV_DATA, + }, { + .name = "artpec8-uart", + .driver_data = (kernel_ulong_t)ARTPEC8_SERIAL_DRV_DATA, + }, + { }, +}; +MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids); + +#ifdef CONFIG_OF +static const struct of_device_id s3c24xx_uart_dt_match[] = { + { .compatible = "samsung,s3c2410-uart", + .data = S3C2410_SERIAL_DRV_DATA }, + { .compatible = "samsung,s3c2412-uart", + .data = S3C2412_SERIAL_DRV_DATA }, + { .compatible = "samsung,s3c2440-uart", + .data = S3C2440_SERIAL_DRV_DATA }, + { .compatible = "samsung,s3c6400-uart", + .data = S3C6400_SERIAL_DRV_DATA }, + { .compatible = "samsung,s5pv210-uart", + .data = S5PV210_SERIAL_DRV_DATA }, + { .compatible = "samsung,exynos4210-uart", + .data = EXYNOS4210_SERIAL_DRV_DATA }, + { .compatible = "samsung,exynos5433-uart", + .data = EXYNOS5433_SERIAL_DRV_DATA }, + { .compatible = "apple,s5l-uart", + .data = S5L_SERIAL_DRV_DATA }, + { .compatible = "samsung,exynos850-uart", + .data = EXYNOS850_SERIAL_DRV_DATA }, + { .compatible = "axis,artpec8-uart", + .data = ARTPEC8_SERIAL_DRV_DATA }, + {}, +}; +MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match); +#endif + +static struct platform_driver samsung_serial_driver = { + .probe = s3c24xx_serial_probe, + .remove = s3c24xx_serial_remove, + .id_table = s3c24xx_serial_driver_ids, + .driver = { + .name = "samsung-uart", + .pm = SERIAL_SAMSUNG_PM_OPS, + .of_match_table = of_match_ptr(s3c24xx_uart_dt_match), + }, +}; + +static int __init samsung_serial_init(void) +{ + int ret; + + s3c24xx_serial_register_console(); + + ret = platform_driver_register(&samsung_serial_driver); + if (ret) { + s3c24xx_serial_unregister_console(); + return ret; + } + + return 0; +} + +static void __exit samsung_serial_exit(void) +{ + platform_driver_unregister(&samsung_serial_driver); + s3c24xx_serial_unregister_console(); +} + +module_init(samsung_serial_init); +module_exit(samsung_serial_exit); + +#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE +/* + * Early console. + */ + +static void wr_reg_barrier(const struct uart_port *port, u32 reg, u32 val) +{ + switch (port->iotype) { + case UPIO_MEM: + writeb(val, portaddr(port, reg)); + break; + case UPIO_MEM32: + writel(val, portaddr(port, reg)); + break; + } +} + +struct samsung_early_console_data { + u32 txfull_mask; + u32 rxfifo_mask; +}; + +static void samsung_early_busyuart(const struct uart_port *port) +{ + while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE)) + ; +} + +static void samsung_early_busyuart_fifo(const struct uart_port *port) +{ + const struct samsung_early_console_data *data = port->private_data; + + while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask) + ; +} + +static void samsung_early_putc(struct uart_port *port, unsigned char c) +{ + if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE) + samsung_early_busyuart_fifo(port); + else + samsung_early_busyuart(port); + + wr_reg_barrier(port, S3C2410_UTXH, c); +} + +static void samsung_early_write(struct console *con, const char *s, + unsigned int n) +{ + struct earlycon_device *dev = con->data; + + uart_console_write(&dev->port, s, n, samsung_early_putc); +} + +static int samsung_early_read(struct console *con, char *s, unsigned int n) +{ + struct earlycon_device *dev = con->data; + const struct samsung_early_console_data *data = dev->port.private_data; + int ch, ufstat, num_read = 0; + + while (num_read < n) { + ufstat = rd_regl(&dev->port, S3C2410_UFSTAT); + if (!(ufstat & data->rxfifo_mask)) + break; + ch = rd_reg(&dev->port, S3C2410_URXH); + if (ch == NO_POLL_CHAR) + break; + + s[num_read++] = ch; + } + + return num_read; +} + +static int __init samsung_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = samsung_early_write; + device->con->read = samsung_early_read; + return 0; +} + +/* S3C2410 */ +static struct samsung_early_console_data s3c2410_early_console_data = { + .txfull_mask = S3C2410_UFSTAT_TXFULL, + .rxfifo_mask = S3C2410_UFSTAT_RXFULL | S3C2410_UFSTAT_RXMASK, +}; + +static int __init s3c2410_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + device->port.private_data = &s3c2410_early_console_data; + return samsung_early_console_setup(device, opt); +} + +OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart", + s3c2410_early_console_setup); + +/* S3C2412, S3C2440, S3C64xx */ +static struct samsung_early_console_data s3c2440_early_console_data = { + .txfull_mask = S3C2440_UFSTAT_TXFULL, + .rxfifo_mask = S3C2440_UFSTAT_RXFULL | S3C2440_UFSTAT_RXMASK, +}; + +static int __init s3c2440_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + device->port.private_data = &s3c2440_early_console_data; + return samsung_early_console_setup(device, opt); +} + +OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart", + s3c2440_early_console_setup); +OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart", + s3c2440_early_console_setup); +OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart", + s3c2440_early_console_setup); + +/* S5PV210, Exynos */ +static struct samsung_early_console_data s5pv210_early_console_data = { + .txfull_mask = S5PV210_UFSTAT_TXFULL, + .rxfifo_mask = S5PV210_UFSTAT_RXFULL | S5PV210_UFSTAT_RXMASK, +}; + +static int __init s5pv210_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + device->port.private_data = &s5pv210_early_console_data; + return samsung_early_console_setup(device, opt); +} + +OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart", + s5pv210_early_console_setup); +OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart", + s5pv210_early_console_setup); +OF_EARLYCON_DECLARE(artpec8, "axis,artpec8-uart", + s5pv210_early_console_setup); + +/* Apple S5L */ +static int __init apple_s5l_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + /* Close enough to S3C2410 for earlycon... */ + device->port.private_data = &s3c2410_early_console_data; + +#ifdef CONFIG_ARM64 + /* ... but we need to override the existing fixmap entry as nGnRnE */ + __set_fixmap(FIX_EARLYCON_MEM_BASE, device->port.mapbase, + __pgprot(PROT_DEVICE_nGnRnE)); +#endif + return samsung_early_console_setup(device, opt); +} + +OF_EARLYCON_DECLARE(s5l, "apple,s5l-uart", apple_s5l_early_console_setup); +#endif + +MODULE_ALIAS("platform:samsung-uart"); +MODULE_DESCRIPTION("Samsung SoC Serial port driver"); +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_LICENSE("GPL v2"); |