diff options
Diffstat (limited to 'drivers/tty/serial/omap-serial.c')
| -rw-r--r-- | drivers/tty/serial/omap-serial.c | 1874 |
1 files changed, 1874 insertions, 0 deletions
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c new file mode 100644 index 000000000..beb7896eb --- /dev/null +++ b/drivers/tty/serial/omap-serial.c @@ -0,0 +1,1874 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver for OMAP-UART controller. + * Based on drivers/serial/8250.c + * + * Copyright (C) 2010 Texas Instruments. + * + * Authors: + * Govindraj R <govindraj.raja@ti.com> + * Thara Gopinath <thara@ti.com> + * + * Note: This driver is made separate from 8250 driver as we cannot + * over load 8250 driver with omap platform specific configuration for + * features like DMA, it makes easier to implement features like DMA and + * hardware flow control and software flow control configuration with + * this driver as required for the omap-platform. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/console.h> +#include <linux/serial.h> +#include <linux/serial_reg.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/serial_core.h> +#include <linux/irq.h> +#include <linux/pm_runtime.h> +#include <linux/pm_wakeirq.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/gpio/consumer.h> +#include <linux/platform_data/serial-omap.h> + +#define OMAP_MAX_HSUART_PORTS 10 + +#define UART_BUILD_REVISION(x, y) (((x) << 8) | (y)) + +#define OMAP_UART_REV_42 0x0402 +#define OMAP_UART_REV_46 0x0406 +#define OMAP_UART_REV_52 0x0502 +#define OMAP_UART_REV_63 0x0603 + +#define OMAP_UART_TX_WAKEUP_EN BIT(7) + +/* Feature flags */ +#define OMAP_UART_WER_HAS_TX_WAKEUP BIT(0) + +#define UART_ERRATA_i202_MDR1_ACCESS BIT(0) +#define UART_ERRATA_i291_DMA_FORCEIDLE BIT(1) + +#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */ + +/* SCR register bitmasks */ +#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7) +#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK (1 << 6) +#define OMAP_UART_SCR_TX_EMPTY (1 << 3) + +/* FCR register bitmasks */ +#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6) +#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK (0x3 << 4) + +/* MVR register bitmasks */ +#define OMAP_UART_MVR_SCHEME_SHIFT 30 + +#define OMAP_UART_LEGACY_MVR_MAJ_MASK 0xf0 +#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT 4 +#define OMAP_UART_LEGACY_MVR_MIN_MASK 0x0f + +#define OMAP_UART_MVR_MAJ_MASK 0x700 +#define OMAP_UART_MVR_MAJ_SHIFT 8 +#define OMAP_UART_MVR_MIN_MASK 0x3f + +#define OMAP_UART_DMA_CH_FREE -1 + +#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA +#define OMAP_MODE13X_SPEED 230400 + +/* WER = 0x7F + * Enable module level wakeup in WER reg + */ +#define OMAP_UART_WER_MOD_WKUP 0x7F + +/* Enable XON/XOFF flow control on output */ +#define OMAP_UART_SW_TX 0x08 + +/* Enable XON/XOFF flow control on input */ +#define OMAP_UART_SW_RX 0x02 + +#define OMAP_UART_SW_CLR 0xF0 + +#define OMAP_UART_TCR_TRIG 0x0F + +struct uart_omap_dma { + u8 uart_dma_tx; + u8 uart_dma_rx; + int rx_dma_channel; + int tx_dma_channel; + dma_addr_t rx_buf_dma_phys; + dma_addr_t tx_buf_dma_phys; + unsigned int uart_base; + /* + * Buffer for rx dma. It is not required for tx because the buffer + * comes from port structure. + */ + unsigned char *rx_buf; + unsigned int prev_rx_dma_pos; + int tx_buf_size; + int tx_dma_used; + int rx_dma_used; + spinlock_t tx_lock; + spinlock_t rx_lock; + /* timer to poll activity on rx dma */ + struct timer_list rx_timer; + unsigned int rx_buf_size; + unsigned int rx_poll_rate; + unsigned int rx_timeout; +}; + +struct uart_omap_port { + struct uart_port port; + struct uart_omap_dma uart_dma; + struct device *dev; + int wakeirq; + + unsigned char ier; + unsigned char lcr; + unsigned char mcr; + unsigned char fcr; + unsigned char efr; + unsigned char dll; + unsigned char dlh; + unsigned char mdr1; + unsigned char scr; + unsigned char wer; + + int use_dma; + /* + * Some bits in registers are cleared on a read, so they must + * be saved whenever the register is read, but the bits will not + * be immediately processed. + */ + unsigned int lsr_break_flag; + unsigned char msr_saved_flags; + char name[20]; + unsigned long port_activity; + int context_loss_cnt; + u32 errata; + u32 features; + + struct gpio_desc *rts_gpiod; + + struct pm_qos_request pm_qos_request; + u32 latency; + u32 calc_latency; + struct work_struct qos_work; + bool is_suspending; + + unsigned int rs485_tx_filter_count; +}; + +#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port))) + +static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS]; + +/* Forward declaration of functions */ +static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1); + +static inline unsigned int serial_in(struct uart_omap_port *up, int offset) +{ + offset <<= up->port.regshift; + return readw(up->port.membase + offset); +} + +static inline void serial_out(struct uart_omap_port *up, int offset, int value) +{ + offset <<= up->port.regshift; + writew(value, up->port.membase + offset); +} + +static inline void serial_omap_clear_fifos(struct uart_omap_port *up) +{ + serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); + serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | + UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); + serial_out(up, UART_FCR, 0); +} + +#ifdef CONFIG_PM +static int serial_omap_get_context_loss_count(struct uart_omap_port *up) +{ + struct omap_uart_port_info *pdata = dev_get_platdata(up->dev); + + if (!pdata || !pdata->get_context_loss_count) + return -EINVAL; + + return pdata->get_context_loss_count(up->dev); +} + +/* REVISIT: Remove this when omap3 boots in device tree only mode */ +static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable) +{ + struct omap_uart_port_info *pdata = dev_get_platdata(up->dev); + + if (!pdata || !pdata->enable_wakeup) + return; + + pdata->enable_wakeup(up->dev, enable); +} +#endif /* CONFIG_PM */ + +/* + * Calculate the absolute difference between the desired and actual baud + * rate for the given mode. + */ +static inline int calculate_baud_abs_diff(struct uart_port *port, + unsigned int baud, unsigned int mode) +{ + unsigned int n = port->uartclk / (mode * baud); + int abs_diff; + + if (n == 0) + n = 1; + + abs_diff = baud - (port->uartclk / (mode * n)); + if (abs_diff < 0) + abs_diff = -abs_diff; + + return abs_diff; +} + +/* + * serial_omap_baud_is_mode16 - check if baud rate is MODE16X + * @port: uart port info + * @baud: baudrate for which mode needs to be determined + * + * Returns true if baud rate is MODE16X and false if MODE13X + * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values, + * and Error Rates" determines modes not for all common baud rates. + * E.g. for 1000000 baud rate mode must be 16x, but according to that + * table it's determined as 13x. + */ +static bool +serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud) +{ + int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13); + int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16); + + return (abs_diff_13 >= abs_diff_16); +} + +/* + * serial_omap_get_divisor - calculate divisor value + * @port: uart port info + * @baud: baudrate for which divisor needs to be calculated. + */ +static unsigned int +serial_omap_get_divisor(struct uart_port *port, unsigned int baud) +{ + unsigned int mode; + + if (!serial_omap_baud_is_mode16(port, baud)) + mode = 13; + else + mode = 16; + return port->uartclk/(mode * baud); +} + +static void serial_omap_enable_ms(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + + dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line); + + up->ier |= UART_IER_MSI; + serial_out(up, UART_IER, up->ier); +} + +static void serial_omap_stop_tx(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + int res; + + /* Handle RS-485 */ + if (port->rs485.flags & SER_RS485_ENABLED) { + if (up->scr & OMAP_UART_SCR_TX_EMPTY) { + /* THR interrupt is fired when both TX FIFO and TX + * shift register are empty. This means there's nothing + * left to transmit now, so make sure the THR interrupt + * is fired when TX FIFO is below the trigger level, + * disable THR interrupts and toggle the RS-485 GPIO + * data direction pin if needed. + */ + up->scr &= ~OMAP_UART_SCR_TX_EMPTY; + serial_out(up, UART_OMAP_SCR, up->scr); + res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ? + 1 : 0; + if (gpiod_get_value(up->rts_gpiod) != res) { + if (port->rs485.delay_rts_after_send > 0) + mdelay( + port->rs485.delay_rts_after_send); + gpiod_set_value(up->rts_gpiod, res); + } + } else { + /* We're asked to stop, but there's still stuff in the + * UART FIFO, so make sure the THR interrupt is fired + * when both TX FIFO and TX shift register are empty. + * The next THR interrupt (if no transmission is started + * in the meantime) will indicate the end of a + * transmission. Therefore we _don't_ disable THR + * interrupts in this situation. + */ + up->scr |= OMAP_UART_SCR_TX_EMPTY; + serial_out(up, UART_OMAP_SCR, up->scr); + return; + } + } + + if (up->ier & UART_IER_THRI) { + up->ier &= ~UART_IER_THRI; + serial_out(up, UART_IER, up->ier); + } +} + +static void serial_omap_stop_rx(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + + up->ier &= ~(UART_IER_RLSI | UART_IER_RDI); + up->port.read_status_mask &= ~UART_LSR_DR; + serial_out(up, UART_IER, up->ier); +} + +static void serial_omap_put_char(struct uart_omap_port *up, unsigned char ch) +{ + serial_out(up, UART_TX, ch); + + if ((up->port.rs485.flags & SER_RS485_ENABLED) && + !(up->port.rs485.flags & SER_RS485_RX_DURING_TX)) + up->rs485_tx_filter_count++; +} + +static void transmit_chars(struct uart_omap_port *up, unsigned int lsr) +{ + struct circ_buf *xmit = &up->port.state->xmit; + int count; + + if (up->port.x_char) { + serial_omap_put_char(up, up->port.x_char); + up->port.icount.tx++; + up->port.x_char = 0; + return; + } + if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { + serial_omap_stop_tx(&up->port); + return; + } + count = up->port.fifosize / 4; + do { + serial_omap_put_char(up, xmit->buf[xmit->tail]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + up->port.icount.tx++; + + if (uart_circ_empty(xmit)) + break; + } while (--count > 0); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(&up->port); + + if (uart_circ_empty(xmit)) + serial_omap_stop_tx(&up->port); +} + +static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up) +{ + if (!(up->ier & UART_IER_THRI)) { + up->ier |= UART_IER_THRI; + serial_out(up, UART_IER, up->ier); + } +} + +static void serial_omap_start_tx(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + int res; + + /* Handle RS-485 */ + if (port->rs485.flags & SER_RS485_ENABLED) { + /* Fire THR interrupts when FIFO is below trigger level */ + up->scr &= ~OMAP_UART_SCR_TX_EMPTY; + serial_out(up, UART_OMAP_SCR, up->scr); + + /* if rts not already enabled */ + res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0; + if (gpiod_get_value(up->rts_gpiod) != res) { + gpiod_set_value(up->rts_gpiod, res); + if (port->rs485.delay_rts_before_send > 0) + mdelay(port->rs485.delay_rts_before_send); + } + } + + if ((port->rs485.flags & SER_RS485_ENABLED) && + !(port->rs485.flags & SER_RS485_RX_DURING_TX)) + up->rs485_tx_filter_count = 0; + + serial_omap_enable_ier_thri(up); +} + +static void serial_omap_throttle(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned long flags; + + spin_lock_irqsave(&up->port.lock, flags); + up->ier &= ~(UART_IER_RLSI | UART_IER_RDI); + serial_out(up, UART_IER, up->ier); + spin_unlock_irqrestore(&up->port.lock, flags); +} + +static void serial_omap_unthrottle(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned long flags; + + spin_lock_irqsave(&up->port.lock, flags); + up->ier |= UART_IER_RLSI | UART_IER_RDI; + serial_out(up, UART_IER, up->ier); + spin_unlock_irqrestore(&up->port.lock, flags); +} + +static unsigned int check_modem_status(struct uart_omap_port *up) +{ + unsigned int status; + + status = serial_in(up, UART_MSR); + status |= up->msr_saved_flags; + up->msr_saved_flags = 0; + if ((status & UART_MSR_ANY_DELTA) == 0) + return status; + + if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI && + up->port.state != NULL) { + if (status & UART_MSR_TERI) + up->port.icount.rng++; + if (status & UART_MSR_DDSR) + up->port.icount.dsr++; + if (status & UART_MSR_DDCD) + uart_handle_dcd_change + (&up->port, status & UART_MSR_DCD); + if (status & UART_MSR_DCTS) + uart_handle_cts_change + (&up->port, status & UART_MSR_CTS); + wake_up_interruptible(&up->port.state->port.delta_msr_wait); + } + + return status; +} + +static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr) +{ + unsigned int flag; + + /* + * Read one data character out to avoid stalling the receiver according + * to the table 23-246 of the omap4 TRM. + */ + if (likely(lsr & UART_LSR_DR)) { + serial_in(up, UART_RX); + if ((up->port.rs485.flags & SER_RS485_ENABLED) && + !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) && + up->rs485_tx_filter_count) + up->rs485_tx_filter_count--; + } + + up->port.icount.rx++; + flag = TTY_NORMAL; + + if (lsr & UART_LSR_BI) { + flag = TTY_BREAK; + lsr &= ~(UART_LSR_FE | UART_LSR_PE); + up->port.icount.brk++; + /* + * We do the SysRQ and SAK checking + * here because otherwise the break + * may get masked by ignore_status_mask + * or read_status_mask. + */ + if (uart_handle_break(&up->port)) + return; + + } + + if (lsr & UART_LSR_PE) { + flag = TTY_PARITY; + up->port.icount.parity++; + } + + if (lsr & UART_LSR_FE) { + flag = TTY_FRAME; + up->port.icount.frame++; + } + + if (lsr & UART_LSR_OE) + up->port.icount.overrun++; + +#ifdef CONFIG_SERIAL_OMAP_CONSOLE + if (up->port.line == up->port.cons->index) { + /* Recover the break flag from console xmit */ + lsr |= up->lsr_break_flag; + } +#endif + uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag); +} + +static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr) +{ + unsigned char ch = 0; + unsigned int flag; + + if (!(lsr & UART_LSR_DR)) + return; + + ch = serial_in(up, UART_RX); + if ((up->port.rs485.flags & SER_RS485_ENABLED) && + !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) && + up->rs485_tx_filter_count) { + up->rs485_tx_filter_count--; + return; + } + + flag = TTY_NORMAL; + up->port.icount.rx++; + + if (uart_handle_sysrq_char(&up->port, ch)) + return; + + uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag); +} + +/** + * serial_omap_irq() - This handles the interrupt from one port + * @irq: uart port irq number + * @dev_id: uart port info + */ +static irqreturn_t serial_omap_irq(int irq, void *dev_id) +{ + struct uart_omap_port *up = dev_id; + unsigned int iir, lsr; + unsigned int type; + irqreturn_t ret = IRQ_NONE; + int max_count = 256; + + spin_lock(&up->port.lock); + + do { + iir = serial_in(up, UART_IIR); + if (iir & UART_IIR_NO_INT) + break; + + ret = IRQ_HANDLED; + lsr = serial_in(up, UART_LSR); + + /* extract IRQ type from IIR register */ + type = iir & 0x3e; + + switch (type) { + case UART_IIR_MSI: + check_modem_status(up); + break; + case UART_IIR_THRI: + transmit_chars(up, lsr); + break; + case UART_IIR_RX_TIMEOUT: + case UART_IIR_RDI: + serial_omap_rdi(up, lsr); + break; + case UART_IIR_RLSI: + serial_omap_rlsi(up, lsr); + break; + case UART_IIR_CTS_RTS_DSR: + /* simply try again */ + break; + case UART_IIR_XOFF: + default: + break; + } + } while (max_count--); + + spin_unlock(&up->port.lock); + + tty_flip_buffer_push(&up->port.state->port); + + up->port_activity = jiffies; + + return ret; +} + +static unsigned int serial_omap_tx_empty(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned long flags; + unsigned int ret = 0; + + dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line); + spin_lock_irqsave(&up->port.lock, flags); + ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0; + spin_unlock_irqrestore(&up->port.lock, flags); + + return ret; +} + +static unsigned int serial_omap_get_mctrl(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned int status; + unsigned int ret = 0; + + status = check_modem_status(up); + + dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line); + + if (status & UART_MSR_DCD) + ret |= TIOCM_CAR; + if (status & UART_MSR_RI) + ret |= TIOCM_RNG; + if (status & UART_MSR_DSR) + ret |= TIOCM_DSR; + if (status & UART_MSR_CTS) + ret |= TIOCM_CTS; + return ret; +} + +static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned char mcr = 0, old_mcr, lcr; + + dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line); + if (mctrl & TIOCM_RTS) + mcr |= UART_MCR_RTS; + if (mctrl & TIOCM_DTR) + mcr |= UART_MCR_DTR; + if (mctrl & TIOCM_OUT1) + mcr |= UART_MCR_OUT1; + if (mctrl & TIOCM_OUT2) + mcr |= UART_MCR_OUT2; + if (mctrl & TIOCM_LOOP) + mcr |= UART_MCR_LOOP; + + old_mcr = serial_in(up, UART_MCR); + old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 | + UART_MCR_DTR | UART_MCR_RTS); + up->mcr = old_mcr | mcr; + serial_out(up, UART_MCR, up->mcr); + + /* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */ + lcr = serial_in(up, UART_LCR); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS)) + up->efr |= UART_EFR_RTS; + else + up->efr &= ~UART_EFR_RTS; + serial_out(up, UART_EFR, up->efr); + serial_out(up, UART_LCR, lcr); +} + +static void serial_omap_break_ctl(struct uart_port *port, int break_state) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned long flags; + + dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line); + spin_lock_irqsave(&up->port.lock, flags); + if (break_state == -1) + up->lcr |= UART_LCR_SBC; + else + up->lcr &= ~UART_LCR_SBC; + serial_out(up, UART_LCR, up->lcr); + spin_unlock_irqrestore(&up->port.lock, flags); +} + +static int serial_omap_startup(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned long flags; + int retval; + + /* + * Allocate the IRQ + */ + retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags, + up->name, up); + if (retval) + return retval; + + /* Optional wake-up IRQ */ + if (up->wakeirq) { + retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq); + if (retval) { + free_irq(up->port.irq, up); + return retval; + } + } + + dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line); + + pm_runtime_get_sync(up->dev); + /* + * Clear the FIFO buffers and disable them. + * (they will be reenabled in set_termios()) + */ + serial_omap_clear_fifos(up); + + /* + * Clear the interrupt registers. + */ + (void) serial_in(up, UART_LSR); + if (serial_in(up, UART_LSR) & UART_LSR_DR) + (void) serial_in(up, UART_RX); + (void) serial_in(up, UART_IIR); + (void) serial_in(up, UART_MSR); + + /* + * Now, initialize the UART + */ + serial_out(up, UART_LCR, UART_LCR_WLEN8); + spin_lock_irqsave(&up->port.lock, flags); + /* + * Most PC uarts need OUT2 raised to enable interrupts. + */ + up->port.mctrl |= TIOCM_OUT2; + serial_omap_set_mctrl(&up->port, up->port.mctrl); + spin_unlock_irqrestore(&up->port.lock, flags); + + up->msr_saved_flags = 0; + /* + * Finally, enable interrupts. Note: Modem status interrupts + * are set via set_termios(), which will be occurring imminently + * anyway, so we don't enable them here. + */ + up->ier = UART_IER_RLSI | UART_IER_RDI; + serial_out(up, UART_IER, up->ier); + + /* Enable module level wake up */ + up->wer = OMAP_UART_WER_MOD_WKUP; + if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP) + up->wer |= OMAP_UART_TX_WAKEUP_EN; + + serial_out(up, UART_OMAP_WER, up->wer); + + up->port_activity = jiffies; + return 0; +} + +static void serial_omap_shutdown(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned long flags; + + dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line); + + /* + * Disable interrupts from this port + */ + up->ier = 0; + serial_out(up, UART_IER, 0); + + spin_lock_irqsave(&up->port.lock, flags); + up->port.mctrl &= ~TIOCM_OUT2; + serial_omap_set_mctrl(&up->port, up->port.mctrl); + spin_unlock_irqrestore(&up->port.lock, flags); + + /* + * Disable break condition and FIFOs + */ + serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC); + serial_omap_clear_fifos(up); + + /* + * Read data port to reset things, and then free the irq + */ + if (serial_in(up, UART_LSR) & UART_LSR_DR) + (void) serial_in(up, UART_RX); + + pm_runtime_put_sync(up->dev); + free_irq(up->port.irq, up); + dev_pm_clear_wake_irq(up->dev); +} + +static void serial_omap_uart_qos_work(struct work_struct *work) +{ + struct uart_omap_port *up = container_of(work, struct uart_omap_port, + qos_work); + + cpu_latency_qos_update_request(&up->pm_qos_request, up->latency); +} + +static void +serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, + const struct ktermios *old) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned char cval = 0; + unsigned long flags; + unsigned int baud, quot; + + cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag)); + + if (termios->c_cflag & CSTOPB) + cval |= UART_LCR_STOP; + if (termios->c_cflag & PARENB) + cval |= UART_LCR_PARITY; + if (!(termios->c_cflag & PARODD)) + cval |= UART_LCR_EPAR; + if (termios->c_cflag & CMSPAR) + cval |= UART_LCR_SPAR; + + /* + * Ask the core to calculate the divisor for us. + */ + + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13); + quot = serial_omap_get_divisor(port, baud); + + /* calculate wakeup latency constraint */ + up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8); + up->latency = up->calc_latency; + schedule_work(&up->qos_work); + + up->dll = quot & 0xff; + up->dlh = quot >> 8; + up->mdr1 = UART_OMAP_MDR1_DISABLE; + + up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 | + UART_FCR_ENABLE_FIFO; + + /* + * Ok, we're now changing the port state. Do it with + * interrupts disabled. + */ + spin_lock_irqsave(&up->port.lock, flags); + + /* + * Update the per-port timeout. + */ + uart_update_timeout(port, termios->c_cflag, baud); + + up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; + if (termios->c_iflag & INPCK) + up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE; + if (termios->c_iflag & (BRKINT | PARMRK)) + up->port.read_status_mask |= UART_LSR_BI; + + /* + * Characters to ignore + */ + up->port.ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; + if (termios->c_iflag & IGNBRK) { + up->port.ignore_status_mask |= UART_LSR_BI; + /* + * If we're ignoring parity and break indicators, + * ignore overruns too (for real raw support). + */ + if (termios->c_iflag & IGNPAR) + up->port.ignore_status_mask |= UART_LSR_OE; + } + + /* + * ignore all characters if CREAD is not set + */ + if ((termios->c_cflag & CREAD) == 0) + up->port.ignore_status_mask |= UART_LSR_DR; + + /* + * Modem status interrupts + */ + up->ier &= ~UART_IER_MSI; + if (UART_ENABLE_MS(&up->port, termios->c_cflag)) + up->ier |= UART_IER_MSI; + serial_out(up, UART_IER, up->ier); + serial_out(up, UART_LCR, cval); /* reset DLAB */ + up->lcr = cval; + up->scr = 0; + + /* FIFOs and DMA Settings */ + + /* FCR can be changed only when the + * baud clock is not running + * DLL_REG and DLH_REG set to 0. + */ + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); + serial_out(up, UART_DLL, 0); + serial_out(up, UART_DLM, 0); + serial_out(up, UART_LCR, 0); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + + up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB; + up->efr &= ~UART_EFR_SCD; + serial_out(up, UART_EFR, up->efr | UART_EFR_ECB); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); + up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR; + serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR); + /* FIFO ENABLE, DMA MODE */ + + up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK; + /* + * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK + * sets Enables the granularity of 1 for TRIGGER RX + * level. Along with setting RX FIFO trigger level + * to 1 (as noted below, 16 characters) and TLR[3:0] + * to zero this will result RX FIFO threshold level + * to 1 character, instead of 16 as noted in comment + * below. + */ + + /* Set receive FIFO threshold to 16 characters and + * transmit FIFO threshold to 32 spaces + */ + up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK; + up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK; + up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 | + UART_FCR_ENABLE_FIFO; + + serial_out(up, UART_FCR, up->fcr); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + + serial_out(up, UART_OMAP_SCR, up->scr); + + /* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */ + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); + serial_out(up, UART_MCR, up->mcr); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + serial_out(up, UART_EFR, up->efr); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); + + /* Protocol, Baud Rate, and Interrupt Settings */ + + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) + serial_omap_mdr1_errataset(up, up->mdr1); + else + serial_out(up, UART_OMAP_MDR1, up->mdr1); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + serial_out(up, UART_EFR, up->efr | UART_EFR_ECB); + + serial_out(up, UART_LCR, 0); + serial_out(up, UART_IER, 0); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + + serial_out(up, UART_DLL, up->dll); /* LS of divisor */ + serial_out(up, UART_DLM, up->dlh); /* MS of divisor */ + + serial_out(up, UART_LCR, 0); + serial_out(up, UART_IER, up->ier); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + + serial_out(up, UART_EFR, up->efr); + serial_out(up, UART_LCR, cval); + + if (!serial_omap_baud_is_mode16(port, baud)) + up->mdr1 = UART_OMAP_MDR1_13X_MODE; + else + up->mdr1 = UART_OMAP_MDR1_16X_MODE; + + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) + serial_omap_mdr1_errataset(up, up->mdr1); + else + serial_out(up, UART_OMAP_MDR1, up->mdr1); + + /* Configure flow control */ + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + + /* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */ + serial_out(up, UART_XON1, termios->c_cc[VSTART]); + serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]); + + /* Enable access to TCR/TLR */ + serial_out(up, UART_EFR, up->efr | UART_EFR_ECB); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); + serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR); + + serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG); + + up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); + + if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) { + /* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */ + up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS; + up->efr |= UART_EFR_CTS; + } else { + /* Disable AUTORTS and AUTOCTS */ + up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS); + } + + if (up->port.flags & UPF_SOFT_FLOW) { + /* clear SW control mode bits */ + up->efr &= OMAP_UART_SW_CLR; + + /* + * IXON Flag: + * Enable XON/XOFF flow control on input. + * Receiver compares XON1, XOFF1. + */ + if (termios->c_iflag & IXON) + up->efr |= OMAP_UART_SW_RX; + + /* + * IXOFF Flag: + * Enable XON/XOFF flow control on output. + * Transmit XON1, XOFF1 + */ + if (termios->c_iflag & IXOFF) { + up->port.status |= UPSTAT_AUTOXOFF; + up->efr |= OMAP_UART_SW_TX; + } + + /* + * IXANY Flag: + * Enable any character to restart output. + * Operation resumes after receiving any + * character after recognition of the XOFF character + */ + if (termios->c_iflag & IXANY) + up->mcr |= UART_MCR_XONANY; + else + up->mcr &= ~UART_MCR_XONANY; + } + serial_out(up, UART_MCR, up->mcr); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + serial_out(up, UART_EFR, up->efr); + serial_out(up, UART_LCR, up->lcr); + + serial_omap_set_mctrl(&up->port, up->port.mctrl); + + spin_unlock_irqrestore(&up->port.lock, flags); + dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line); +} + +static void +serial_omap_pm(struct uart_port *port, unsigned int state, + unsigned int oldstate) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned char efr; + + dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + efr = serial_in(up, UART_EFR); + serial_out(up, UART_EFR, efr | UART_EFR_ECB); + serial_out(up, UART_LCR, 0); + + serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); + serial_out(up, UART_EFR, efr); + serial_out(up, UART_LCR, 0); +} + +static void serial_omap_release_port(struct uart_port *port) +{ + dev_dbg(port->dev, "serial_omap_release_port+\n"); +} + +static int serial_omap_request_port(struct uart_port *port) +{ + dev_dbg(port->dev, "serial_omap_request_port+\n"); + return 0; +} + +static void serial_omap_config_port(struct uart_port *port, int flags) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + + dev_dbg(up->port.dev, "serial_omap_config_port+%d\n", + up->port.line); + up->port.type = PORT_OMAP; + up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW; +} + +static int +serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + /* we don't want the core code to modify any port params */ + dev_dbg(port->dev, "serial_omap_verify_port+\n"); + return -EINVAL; +} + +static const char * +serial_omap_type(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + + dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line); + return up->name; +} + +static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up) +{ + unsigned int status, tmout = 10000; + + /* Wait up to 10ms for the character(s) to be sent. */ + do { + status = serial_in(up, UART_LSR); + + if (status & UART_LSR_BI) + up->lsr_break_flag = UART_LSR_BI; + + if (--tmout == 0) + break; + udelay(1); + } while (!uart_lsr_tx_empty(status)); + + /* Wait up to 1s for flow control if necessary */ + if (up->port.flags & UPF_CONS_FLOW) { + tmout = 1000000; + for (tmout = 1000000; tmout; tmout--) { + unsigned int msr = serial_in(up, UART_MSR); + + up->msr_saved_flags |= msr & MSR_SAVE_FLAGS; + if (msr & UART_MSR_CTS) + break; + + udelay(1); + } + } +} + +#ifdef CONFIG_CONSOLE_POLL + +static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + + wait_for_xmitr(up); + serial_out(up, UART_TX, ch); +} + +static int serial_omap_poll_get_char(struct uart_port *port) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned int status; + + status = serial_in(up, UART_LSR); + if (!(status & UART_LSR_DR)) { + status = NO_POLL_CHAR; + goto out; + } + + status = serial_in(up, UART_RX); + +out: + return status; +} + +#endif /* CONFIG_CONSOLE_POLL */ + +#ifdef CONFIG_SERIAL_OMAP_CONSOLE + +#ifdef CONFIG_SERIAL_EARLYCON +static unsigned int omap_serial_early_in(struct uart_port *port, int offset) +{ + offset <<= port->regshift; + return readw(port->membase + offset); +} + +static void omap_serial_early_out(struct uart_port *port, int offset, + int value) +{ + offset <<= port->regshift; + writew(value, port->membase + offset); +} + +static void omap_serial_early_putc(struct uart_port *port, unsigned char c) +{ + unsigned int status; + + for (;;) { + status = omap_serial_early_in(port, UART_LSR); + if (uart_lsr_tx_empty(status)) + break; + cpu_relax(); + } + omap_serial_early_out(port, UART_TX, c); +} + +static void early_omap_serial_write(struct console *console, const char *s, + unsigned int count) +{ + struct earlycon_device *device = console->data; + struct uart_port *port = &device->port; + + uart_console_write(port, s, count, omap_serial_early_putc); +} + +static int __init early_omap_serial_setup(struct earlycon_device *device, + const char *options) +{ + struct uart_port *port = &device->port; + + if (!(device->port.membase || device->port.iobase)) + return -ENODEV; + + port->regshift = 2; + device->con->write = early_omap_serial_write; + return 0; +} + +OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup); +OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup); +OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup); +#endif /* CONFIG_SERIAL_EARLYCON */ + +static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS]; + +static struct uart_driver serial_omap_reg; + +static void serial_omap_console_putchar(struct uart_port *port, unsigned char ch) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + + wait_for_xmitr(up); + serial_out(up, UART_TX, ch); +} + +static void +serial_omap_console_write(struct console *co, const char *s, + unsigned int count) +{ + struct uart_omap_port *up = serial_omap_console_ports[co->index]; + unsigned long flags; + unsigned int ier; + int locked = 1; + + local_irq_save(flags); + if (up->port.sysrq) + locked = 0; + else if (oops_in_progress) + locked = spin_trylock(&up->port.lock); + else + spin_lock(&up->port.lock); + + /* + * First save the IER then disable the interrupts + */ + ier = serial_in(up, UART_IER); + serial_out(up, UART_IER, 0); + + uart_console_write(&up->port, s, count, serial_omap_console_putchar); + + /* + * Finally, wait for transmitter to become empty + * and restore the IER + */ + wait_for_xmitr(up); + serial_out(up, UART_IER, ier); + /* + * The receive handling will happen properly because the + * receive ready bit will still be set; it is not cleared + * on read. However, modem control will not, we must + * call it if we have saved something in the saved flags + * while processing with interrupts off. + */ + if (up->msr_saved_flags) + check_modem_status(up); + + if (locked) + spin_unlock(&up->port.lock); + local_irq_restore(flags); +} + +static int __init +serial_omap_console_setup(struct console *co, char *options) +{ + struct uart_omap_port *up; + int baud = 115200; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (serial_omap_console_ports[co->index] == NULL) + return -ENODEV; + up = serial_omap_console_ports[co->index]; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(&up->port, co, baud, parity, bits, flow); +} + +static struct console serial_omap_console = { + .name = OMAP_SERIAL_NAME, + .write = serial_omap_console_write, + .device = uart_console_device, + .setup = serial_omap_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &serial_omap_reg, +}; + +static void serial_omap_add_console_port(struct uart_omap_port *up) +{ + serial_omap_console_ports[up->port.line] = up; +} + +#define OMAP_CONSOLE (&serial_omap_console) + +#else + +#define OMAP_CONSOLE NULL + +static inline void serial_omap_add_console_port(struct uart_omap_port *up) +{} + +#endif + +/* Enable or disable the rs485 support */ +static int +serial_omap_config_rs485(struct uart_port *port, struct ktermios *termios, + struct serial_rs485 *rs485) +{ + struct uart_omap_port *up = to_uart_omap_port(port); + unsigned int mode; + int val; + + /* Disable interrupts from this port */ + mode = up->ier; + up->ier = 0; + serial_out(up, UART_IER, 0); + + /* enable / disable rts */ + val = (rs485->flags & SER_RS485_ENABLED) ? + SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND; + val = (rs485->flags & val) ? 1 : 0; + gpiod_set_value(up->rts_gpiod, val); + + /* Enable interrupts */ + up->ier = mode; + serial_out(up, UART_IER, up->ier); + + /* If RS-485 is disabled, make sure the THR interrupt is fired when + * TX FIFO is below the trigger level. + */ + if (!(rs485->flags & SER_RS485_ENABLED) && + (up->scr & OMAP_UART_SCR_TX_EMPTY)) { + up->scr &= ~OMAP_UART_SCR_TX_EMPTY; + serial_out(up, UART_OMAP_SCR, up->scr); + } + + return 0; +} + +static const struct uart_ops serial_omap_pops = { + .tx_empty = serial_omap_tx_empty, + .set_mctrl = serial_omap_set_mctrl, + .get_mctrl = serial_omap_get_mctrl, + .stop_tx = serial_omap_stop_tx, + .start_tx = serial_omap_start_tx, + .throttle = serial_omap_throttle, + .unthrottle = serial_omap_unthrottle, + .stop_rx = serial_omap_stop_rx, + .enable_ms = serial_omap_enable_ms, + .break_ctl = serial_omap_break_ctl, + .startup = serial_omap_startup, + .shutdown = serial_omap_shutdown, + .set_termios = serial_omap_set_termios, + .pm = serial_omap_pm, + .type = serial_omap_type, + .release_port = serial_omap_release_port, + .request_port = serial_omap_request_port, + .config_port = serial_omap_config_port, + .verify_port = serial_omap_verify_port, +#ifdef CONFIG_CONSOLE_POLL + .poll_put_char = serial_omap_poll_put_char, + .poll_get_char = serial_omap_poll_get_char, +#endif +}; + +static struct uart_driver serial_omap_reg = { + .owner = THIS_MODULE, + .driver_name = "OMAP-SERIAL", + .dev_name = OMAP_SERIAL_NAME, + .nr = OMAP_MAX_HSUART_PORTS, + .cons = OMAP_CONSOLE, +}; + +#ifdef CONFIG_PM_SLEEP +static int serial_omap_prepare(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + up->is_suspending = true; + + return 0; +} + +static void serial_omap_complete(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + up->is_suspending = false; +} + +static int serial_omap_suspend(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + uart_suspend_port(&serial_omap_reg, &up->port); + flush_work(&up->qos_work); + + if (device_may_wakeup(dev)) + serial_omap_enable_wakeup(up, true); + else + serial_omap_enable_wakeup(up, false); + + return 0; +} + +static int serial_omap_resume(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + serial_omap_enable_wakeup(up, false); + + uart_resume_port(&serial_omap_reg, &up->port); + + return 0; +} +#else +#define serial_omap_prepare NULL +#define serial_omap_complete NULL +#endif /* CONFIG_PM_SLEEP */ + +static void omap_serial_fill_features_erratas(struct uart_omap_port *up) +{ + u32 mvr, scheme; + u16 revision, major, minor; + + mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift)); + + /* Check revision register scheme */ + scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT; + + switch (scheme) { + case 0: /* Legacy Scheme: OMAP2/3 */ + /* MINOR_REV[0:4], MAJOR_REV[4:7] */ + major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >> + OMAP_UART_LEGACY_MVR_MAJ_SHIFT; + minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK); + break; + case 1: + /* New Scheme: OMAP4+ */ + /* MINOR_REV[0:5], MAJOR_REV[8:10] */ + major = (mvr & OMAP_UART_MVR_MAJ_MASK) >> + OMAP_UART_MVR_MAJ_SHIFT; + minor = (mvr & OMAP_UART_MVR_MIN_MASK); + break; + default: + dev_warn(up->dev, + "Unknown %s revision, defaulting to highest\n", + up->name); + /* highest possible revision */ + major = 0xff; + minor = 0xff; + } + + /* normalize revision for the driver */ + revision = UART_BUILD_REVISION(major, minor); + + switch (revision) { + case OMAP_UART_REV_46: + up->errata |= (UART_ERRATA_i202_MDR1_ACCESS | + UART_ERRATA_i291_DMA_FORCEIDLE); + break; + case OMAP_UART_REV_52: + up->errata |= (UART_ERRATA_i202_MDR1_ACCESS | + UART_ERRATA_i291_DMA_FORCEIDLE); + up->features |= OMAP_UART_WER_HAS_TX_WAKEUP; + break; + case OMAP_UART_REV_63: + up->errata |= UART_ERRATA_i202_MDR1_ACCESS; + up->features |= OMAP_UART_WER_HAS_TX_WAKEUP; + break; + default: + break; + } +} + +static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev) +{ + struct omap_uart_port_info *omap_up_info; + + omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL); + if (!omap_up_info) + return NULL; /* out of memory */ + + of_property_read_u32(dev->of_node, "clock-frequency", + &omap_up_info->uartclk); + + omap_up_info->flags = UPF_BOOT_AUTOCONF; + + return omap_up_info; +} + +static const struct serial_rs485 serial_omap_rs485_supported = { + .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND | + SER_RS485_RX_DURING_TX, + .delay_rts_before_send = 1, + .delay_rts_after_send = 1, +}; + +static int serial_omap_probe_rs485(struct uart_omap_port *up, + struct device *dev) +{ + struct serial_rs485 *rs485conf = &up->port.rs485; + struct device_node *np = dev->of_node; + enum gpiod_flags gflags; + int ret; + + rs485conf->flags = 0; + up->rts_gpiod = NULL; + + if (!np) + return 0; + + up->port.rs485_config = serial_omap_config_rs485; + up->port.rs485_supported = serial_omap_rs485_supported; + + ret = uart_get_rs485_mode(&up->port); + if (ret) + return ret; + + if (of_property_read_bool(np, "rs485-rts-active-high")) { + rs485conf->flags |= SER_RS485_RTS_ON_SEND; + rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND; + } else { + rs485conf->flags &= ~SER_RS485_RTS_ON_SEND; + rs485conf->flags |= SER_RS485_RTS_AFTER_SEND; + } + + /* check for tx enable gpio */ + gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ? + GPIOD_OUT_HIGH : GPIOD_OUT_LOW; + up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags); + if (IS_ERR(up->rts_gpiod)) { + ret = PTR_ERR(up->rts_gpiod); + if (ret == -EPROBE_DEFER) + return ret; + + up->rts_gpiod = NULL; + up->port.rs485_supported = (const struct serial_rs485) { }; + if (rs485conf->flags & SER_RS485_ENABLED) { + dev_err(dev, "disabling RS-485 (rts-gpio missing in device tree)\n"); + memset(rs485conf, 0, sizeof(*rs485conf)); + } + } else { + gpiod_set_consumer_name(up->rts_gpiod, "omap-serial"); + } + + return 0; +} + +static int serial_omap_probe(struct platform_device *pdev) +{ + struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev); + struct uart_omap_port *up; + struct resource *mem; + void __iomem *base; + int uartirq = 0; + int wakeirq = 0; + int ret; + + /* The optional wakeirq may be specified in the board dts file */ + if (pdev->dev.of_node) { + uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0); + if (!uartirq) + return -EPROBE_DEFER; + wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1); + omap_up_info = of_get_uart_port_info(&pdev->dev); + pdev->dev.platform_data = omap_up_info; + } else { + uartirq = platform_get_irq(pdev, 0); + if (uartirq < 0) + return -EPROBE_DEFER; + } + + up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL); + if (!up) + return -ENOMEM; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(base)) + return PTR_ERR(base); + + up->dev = &pdev->dev; + up->port.dev = &pdev->dev; + up->port.type = PORT_OMAP; + up->port.iotype = UPIO_MEM; + up->port.irq = uartirq; + up->port.regshift = 2; + up->port.fifosize = 64; + up->port.ops = &serial_omap_pops; + up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE); + + if (pdev->dev.of_node) + ret = of_alias_get_id(pdev->dev.of_node, "serial"); + else + ret = pdev->id; + + if (ret < 0) { + dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n", + ret); + goto err_port_line; + } + up->port.line = ret; + + if (up->port.line >= OMAP_MAX_HSUART_PORTS) { + dev_err(&pdev->dev, "uart ID %d > MAX %d.\n", up->port.line, + OMAP_MAX_HSUART_PORTS); + ret = -ENXIO; + goto err_port_line; + } + + up->wakeirq = wakeirq; + if (!up->wakeirq) + dev_info(up->port.dev, "no wakeirq for uart%d\n", + up->port.line); + + sprintf(up->name, "OMAP UART%d", up->port.line); + up->port.mapbase = mem->start; + up->port.membase = base; + up->port.flags = omap_up_info->flags; + up->port.uartclk = omap_up_info->uartclk; + if (!up->port.uartclk) { + up->port.uartclk = DEFAULT_CLK_SPEED; + dev_warn(&pdev->dev, + "No clock speed specified: using default: %d\n", + DEFAULT_CLK_SPEED); + } + + ret = serial_omap_probe_rs485(up, &pdev->dev); + if (ret < 0) + goto err_rs485; + + up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; + up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; + cpu_latency_qos_add_request(&up->pm_qos_request, up->latency); + INIT_WORK(&up->qos_work, serial_omap_uart_qos_work); + + platform_set_drvdata(pdev, up); + if (omap_up_info->autosuspend_timeout == 0) + omap_up_info->autosuspend_timeout = -1; + + device_init_wakeup(up->dev, true); + + pm_runtime_enable(&pdev->dev); + + pm_runtime_get_sync(&pdev->dev); + + omap_serial_fill_features_erratas(up); + + ui[up->port.line] = up; + serial_omap_add_console_port(up); + + ret = uart_add_one_port(&serial_omap_reg, &up->port); + if (ret != 0) + goto err_add_port; + + return 0; + +err_add_port: + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + cpu_latency_qos_remove_request(&up->pm_qos_request); + device_init_wakeup(up->dev, false); +err_rs485: +err_port_line: + return ret; +} + +static int serial_omap_remove(struct platform_device *dev) +{ + struct uart_omap_port *up = platform_get_drvdata(dev); + + pm_runtime_get_sync(up->dev); + + uart_remove_one_port(&serial_omap_reg, &up->port); + + pm_runtime_put_sync(up->dev); + pm_runtime_disable(up->dev); + cpu_latency_qos_remove_request(&up->pm_qos_request); + device_init_wakeup(&dev->dev, false); + + return 0; +} + +/* + * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460) + * The access to uart register after MDR1 Access + * causes UART to corrupt data. + * + * Need a delay = + * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS) + * give 10 times as much + */ +static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1) +{ + u8 timeout = 255; + + serial_out(up, UART_OMAP_MDR1, mdr1); + udelay(2); + serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT | + UART_FCR_CLEAR_RCVR); + /* + * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and + * TX_FIFO_E bit is 1. + */ + while (UART_LSR_THRE != (serial_in(up, UART_LSR) & + (UART_LSR_THRE | UART_LSR_DR))) { + timeout--; + if (!timeout) { + /* Should *never* happen. we warn and carry on */ + dev_crit(up->dev, "Errata i202: timedout %x\n", + serial_in(up, UART_LSR)); + break; + } + udelay(1); + } +} + +#ifdef CONFIG_PM +static void serial_omap_restore_context(struct uart_omap_port *up) +{ + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) + serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE); + else + serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE); + + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */ + serial_out(up, UART_EFR, UART_EFR_ECB); + serial_out(up, UART_LCR, 0x0); /* Operational mode */ + serial_out(up, UART_IER, 0x0); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */ + serial_out(up, UART_DLL, up->dll); + serial_out(up, UART_DLM, up->dlh); + serial_out(up, UART_LCR, 0x0); /* Operational mode */ + serial_out(up, UART_IER, up->ier); + serial_out(up, UART_FCR, up->fcr); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); + serial_out(up, UART_MCR, up->mcr); + serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */ + serial_out(up, UART_OMAP_SCR, up->scr); + serial_out(up, UART_EFR, up->efr); + serial_out(up, UART_LCR, up->lcr); + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) + serial_omap_mdr1_errataset(up, up->mdr1); + else + serial_out(up, UART_OMAP_MDR1, up->mdr1); + serial_out(up, UART_OMAP_WER, up->wer); +} + +static int serial_omap_runtime_suspend(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + if (!up) + return -EINVAL; + + /* + * When using 'no_console_suspend', the console UART must not be + * suspended. Since driver suspend is managed by runtime suspend, + * preventing runtime suspend (by returning error) will keep device + * active during suspend. + */ + if (up->is_suspending && !console_suspend_enabled && + uart_console(&up->port)) + return -EBUSY; + + up->context_loss_cnt = serial_omap_get_context_loss_count(up); + + serial_omap_enable_wakeup(up, true); + + up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE; + schedule_work(&up->qos_work); + + return 0; +} + +static int serial_omap_runtime_resume(struct device *dev) +{ + struct uart_omap_port *up = dev_get_drvdata(dev); + + int loss_cnt = serial_omap_get_context_loss_count(up); + + serial_omap_enable_wakeup(up, false); + + if (loss_cnt < 0) { + dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n", + loss_cnt); + serial_omap_restore_context(up); + } else if (up->context_loss_cnt != loss_cnt) { + serial_omap_restore_context(up); + } + up->latency = up->calc_latency; + schedule_work(&up->qos_work); + + return 0; +} +#endif + +static const struct dev_pm_ops serial_omap_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume) + SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend, + serial_omap_runtime_resume, NULL) + .prepare = serial_omap_prepare, + .complete = serial_omap_complete, +}; + +#if defined(CONFIG_OF) +static const struct of_device_id omap_serial_of_match[] = { + { .compatible = "ti,omap2-uart" }, + { .compatible = "ti,omap3-uart" }, + { .compatible = "ti,omap4-uart" }, + {}, +}; +MODULE_DEVICE_TABLE(of, omap_serial_of_match); +#endif + +static struct platform_driver serial_omap_driver = { + .probe = serial_omap_probe, + .remove = serial_omap_remove, + .driver = { + .name = OMAP_SERIAL_DRIVER_NAME, + .pm = &serial_omap_dev_pm_ops, + .of_match_table = of_match_ptr(omap_serial_of_match), + }, +}; + +static int __init serial_omap_init(void) +{ + int ret; + + ret = uart_register_driver(&serial_omap_reg); + if (ret != 0) + return ret; + ret = platform_driver_register(&serial_omap_driver); + if (ret != 0) + uart_unregister_driver(&serial_omap_reg); + return ret; +} + +static void __exit serial_omap_exit(void) +{ + platform_driver_unregister(&serial_omap_driver); + uart_unregister_driver(&serial_omap_reg); +} + +module_init(serial_omap_init); +module_exit(serial_omap_exit); + +MODULE_DESCRIPTION("OMAP High Speed UART driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Texas Instruments Inc"); |