diff options
Diffstat (limited to 'drivers/tty/serial/meson_uart.c')
| -rw-r--r-- | drivers/tty/serial/meson_uart.c | 847 |
1 files changed, 847 insertions, 0 deletions
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c new file mode 100644 index 000000000..8f6d54c04 --- /dev/null +++ b/drivers/tty/serial/meson_uart.c @@ -0,0 +1,847 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Based on meson_uart.c, by AMLOGIC, INC. + * + * Copyright (C) 2014 Carlo Caione <carlo@caione.org> + */ + +#include <linux/clk.h> +#include <linux/console.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> + +/* Register offsets */ +#define AML_UART_WFIFO 0x00 +#define AML_UART_RFIFO 0x04 +#define AML_UART_CONTROL 0x08 +#define AML_UART_STATUS 0x0c +#define AML_UART_MISC 0x10 +#define AML_UART_REG5 0x14 + +/* AML_UART_CONTROL bits */ +#define AML_UART_TX_EN BIT(12) +#define AML_UART_RX_EN BIT(13) +#define AML_UART_TWO_WIRE_EN BIT(15) +#define AML_UART_STOP_BIT_LEN_MASK (0x03 << 16) +#define AML_UART_STOP_BIT_1SB (0x00 << 16) +#define AML_UART_STOP_BIT_2SB (0x01 << 16) +#define AML_UART_PARITY_TYPE BIT(18) +#define AML_UART_PARITY_EN BIT(19) +#define AML_UART_TX_RST BIT(22) +#define AML_UART_RX_RST BIT(23) +#define AML_UART_CLEAR_ERR BIT(24) +#define AML_UART_RX_INT_EN BIT(27) +#define AML_UART_TX_INT_EN BIT(28) +#define AML_UART_DATA_LEN_MASK (0x03 << 20) +#define AML_UART_DATA_LEN_8BIT (0x00 << 20) +#define AML_UART_DATA_LEN_7BIT (0x01 << 20) +#define AML_UART_DATA_LEN_6BIT (0x02 << 20) +#define AML_UART_DATA_LEN_5BIT (0x03 << 20) + +/* AML_UART_STATUS bits */ +#define AML_UART_PARITY_ERR BIT(16) +#define AML_UART_FRAME_ERR BIT(17) +#define AML_UART_TX_FIFO_WERR BIT(18) +#define AML_UART_RX_EMPTY BIT(20) +#define AML_UART_TX_FULL BIT(21) +#define AML_UART_TX_EMPTY BIT(22) +#define AML_UART_XMIT_BUSY BIT(25) +#define AML_UART_ERR (AML_UART_PARITY_ERR | \ + AML_UART_FRAME_ERR | \ + AML_UART_TX_FIFO_WERR) + +/* AML_UART_MISC bits */ +#define AML_UART_XMIT_IRQ(c) (((c) & 0xff) << 8) +#define AML_UART_RECV_IRQ(c) ((c) & 0xff) + +/* AML_UART_REG5 bits */ +#define AML_UART_BAUD_MASK 0x7fffff +#define AML_UART_BAUD_USE BIT(23) +#define AML_UART_BAUD_XTAL BIT(24) +#define AML_UART_BAUD_XTAL_DIV2 BIT(27) + +#define AML_UART_PORT_NUM 12 +#define AML_UART_PORT_OFFSET 6 +#define AML_UART_DEV_NAME "ttyAML" + +#define AML_UART_POLL_USEC 5 +#define AML_UART_TIMEOUT_USEC 10000 + +static struct uart_driver meson_uart_driver; + +static struct uart_port *meson_ports[AML_UART_PORT_NUM]; + +struct meson_uart_data { + bool has_xtal_div2; +}; + +static void meson_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ +} + +static unsigned int meson_uart_get_mctrl(struct uart_port *port) +{ + return TIOCM_CTS; +} + +static unsigned int meson_uart_tx_empty(struct uart_port *port) +{ + u32 val; + + val = readl(port->membase + AML_UART_STATUS); + val &= (AML_UART_TX_EMPTY | AML_UART_XMIT_BUSY); + return (val == AML_UART_TX_EMPTY) ? TIOCSER_TEMT : 0; +} + +static void meson_uart_stop_tx(struct uart_port *port) +{ + u32 val; + + val = readl(port->membase + AML_UART_CONTROL); + val &= ~AML_UART_TX_INT_EN; + writel(val, port->membase + AML_UART_CONTROL); +} + +static void meson_uart_stop_rx(struct uart_port *port) +{ + u32 val; + + val = readl(port->membase + AML_UART_CONTROL); + val &= ~AML_UART_RX_EN; + writel(val, port->membase + AML_UART_CONTROL); +} + +static void meson_uart_shutdown(struct uart_port *port) +{ + unsigned long flags; + u32 val; + + free_irq(port->irq, port); + + spin_lock_irqsave(&port->lock, flags); + + val = readl(port->membase + AML_UART_CONTROL); + val &= ~AML_UART_RX_EN; + val &= ~(AML_UART_RX_INT_EN | AML_UART_TX_INT_EN); + writel(val, port->membase + AML_UART_CONTROL); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static void meson_uart_start_tx(struct uart_port *port) +{ + struct circ_buf *xmit = &port->state->xmit; + unsigned int ch; + u32 val; + + if (uart_tx_stopped(port)) { + meson_uart_stop_tx(port); + return; + } + + while (!(readl(port->membase + AML_UART_STATUS) & AML_UART_TX_FULL)) { + if (port->x_char) { + writel(port->x_char, port->membase + AML_UART_WFIFO); + port->icount.tx++; + port->x_char = 0; + continue; + } + + if (uart_circ_empty(xmit)) + break; + + ch = xmit->buf[xmit->tail]; + writel(ch, port->membase + AML_UART_WFIFO); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + } + + if (!uart_circ_empty(xmit)) { + val = readl(port->membase + AML_UART_CONTROL); + val |= AML_UART_TX_INT_EN; + writel(val, port->membase + AML_UART_CONTROL); + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); +} + +static void meson_receive_chars(struct uart_port *port) +{ + struct tty_port *tport = &port->state->port; + char flag; + u32 ostatus, status, ch, mode; + + do { + flag = TTY_NORMAL; + port->icount.rx++; + ostatus = status = readl(port->membase + AML_UART_STATUS); + + if (status & AML_UART_ERR) { + if (status & AML_UART_TX_FIFO_WERR) + port->icount.overrun++; + else if (status & AML_UART_FRAME_ERR) + port->icount.frame++; + else if (status & AML_UART_PARITY_ERR) + port->icount.frame++; + + mode = readl(port->membase + AML_UART_CONTROL); + mode |= AML_UART_CLEAR_ERR; + writel(mode, port->membase + AML_UART_CONTROL); + + /* It doesn't clear to 0 automatically */ + mode &= ~AML_UART_CLEAR_ERR; + writel(mode, port->membase + AML_UART_CONTROL); + + status &= port->read_status_mask; + if (status & AML_UART_FRAME_ERR) + flag = TTY_FRAME; + else if (status & AML_UART_PARITY_ERR) + flag = TTY_PARITY; + } + + ch = readl(port->membase + AML_UART_RFIFO); + ch &= 0xff; + + if ((ostatus & AML_UART_FRAME_ERR) && (ch == 0)) { + port->icount.brk++; + flag = TTY_BREAK; + if (uart_handle_break(port)) + continue; + } + + if (uart_handle_sysrq_char(port, ch)) + continue; + + if ((status & port->ignore_status_mask) == 0) + tty_insert_flip_char(tport, ch, flag); + + if (status & AML_UART_TX_FIFO_WERR) + tty_insert_flip_char(tport, 0, TTY_OVERRUN); + + } while (!(readl(port->membase + AML_UART_STATUS) & AML_UART_RX_EMPTY)); + + tty_flip_buffer_push(tport); +} + +static irqreturn_t meson_uart_interrupt(int irq, void *dev_id) +{ + struct uart_port *port = (struct uart_port *)dev_id; + + spin_lock(&port->lock); + + if (!(readl(port->membase + AML_UART_STATUS) & AML_UART_RX_EMPTY)) + meson_receive_chars(port); + + if (!(readl(port->membase + AML_UART_STATUS) & AML_UART_TX_FULL)) { + if (readl(port->membase + AML_UART_CONTROL) & AML_UART_TX_INT_EN) + meson_uart_start_tx(port); + } + + spin_unlock(&port->lock); + + return IRQ_HANDLED; +} + +static const char *meson_uart_type(struct uart_port *port) +{ + return (port->type == PORT_MESON) ? "meson_uart" : NULL; +} + +/* + * This function is called only from probe() using a temporary io mapping + * in order to perform a reset before setting up the device. Since the + * temporarily mapped region was successfully requested, there can be no + * console on this port at this time. Hence it is not necessary for this + * function to acquire the port->lock. (Since there is no console on this + * port at this time, the port->lock is not initialized yet.) + */ +static void meson_uart_reset(struct uart_port *port) +{ + u32 val; + + val = readl(port->membase + AML_UART_CONTROL); + val |= (AML_UART_RX_RST | AML_UART_TX_RST | AML_UART_CLEAR_ERR); + writel(val, port->membase + AML_UART_CONTROL); + + val &= ~(AML_UART_RX_RST | AML_UART_TX_RST | AML_UART_CLEAR_ERR); + writel(val, port->membase + AML_UART_CONTROL); +} + +static int meson_uart_startup(struct uart_port *port) +{ + unsigned long flags; + u32 val; + int ret = 0; + + spin_lock_irqsave(&port->lock, flags); + + val = readl(port->membase + AML_UART_CONTROL); + val |= AML_UART_CLEAR_ERR; + writel(val, port->membase + AML_UART_CONTROL); + val &= ~AML_UART_CLEAR_ERR; + writel(val, port->membase + AML_UART_CONTROL); + + val |= (AML_UART_RX_EN | AML_UART_TX_EN); + writel(val, port->membase + AML_UART_CONTROL); + + val |= (AML_UART_RX_INT_EN | AML_UART_TX_INT_EN); + writel(val, port->membase + AML_UART_CONTROL); + + val = (AML_UART_RECV_IRQ(1) | AML_UART_XMIT_IRQ(port->fifosize / 2)); + writel(val, port->membase + AML_UART_MISC); + + spin_unlock_irqrestore(&port->lock, flags); + + ret = request_irq(port->irq, meson_uart_interrupt, 0, + port->name, port); + + return ret; +} + +static void meson_uart_change_speed(struct uart_port *port, unsigned long baud) +{ + const struct meson_uart_data *private_data = port->private_data; + u32 val = 0; + + while (!meson_uart_tx_empty(port)) + cpu_relax(); + + if (port->uartclk == 24000000) { + unsigned int xtal_div = 3; + + if (private_data && private_data->has_xtal_div2) { + xtal_div = 2; + val |= AML_UART_BAUD_XTAL_DIV2; + } + val |= DIV_ROUND_CLOSEST(port->uartclk / xtal_div, baud) - 1; + val |= AML_UART_BAUD_XTAL; + } else { + val = DIV_ROUND_CLOSEST(port->uartclk / 4, baud) - 1; + } + val |= AML_UART_BAUD_USE; + writel(val, port->membase + AML_UART_REG5); +} + +static void meson_uart_set_termios(struct uart_port *port, + struct ktermios *termios, + const struct ktermios *old) +{ + unsigned int cflags, iflags, baud; + unsigned long flags; + u32 val; + + spin_lock_irqsave(&port->lock, flags); + + cflags = termios->c_cflag; + iflags = termios->c_iflag; + + val = readl(port->membase + AML_UART_CONTROL); + + val &= ~AML_UART_DATA_LEN_MASK; + switch (cflags & CSIZE) { + case CS8: + val |= AML_UART_DATA_LEN_8BIT; + break; + case CS7: + val |= AML_UART_DATA_LEN_7BIT; + break; + case CS6: + val |= AML_UART_DATA_LEN_6BIT; + break; + case CS5: + val |= AML_UART_DATA_LEN_5BIT; + break; + } + + if (cflags & PARENB) + val |= AML_UART_PARITY_EN; + else + val &= ~AML_UART_PARITY_EN; + + if (cflags & PARODD) + val |= AML_UART_PARITY_TYPE; + else + val &= ~AML_UART_PARITY_TYPE; + + val &= ~AML_UART_STOP_BIT_LEN_MASK; + if (cflags & CSTOPB) + val |= AML_UART_STOP_BIT_2SB; + else + val |= AML_UART_STOP_BIT_1SB; + + if (cflags & CRTSCTS) { + if (port->flags & UPF_HARD_FLOW) + val &= ~AML_UART_TWO_WIRE_EN; + else + termios->c_cflag &= ~CRTSCTS; + } else { + val |= AML_UART_TWO_WIRE_EN; + } + + writel(val, port->membase + AML_UART_CONTROL); + + baud = uart_get_baud_rate(port, termios, old, 50, 4000000); + meson_uart_change_speed(port, baud); + + port->read_status_mask = AML_UART_TX_FIFO_WERR; + if (iflags & INPCK) + port->read_status_mask |= AML_UART_PARITY_ERR | + AML_UART_FRAME_ERR; + + port->ignore_status_mask = 0; + if (iflags & IGNPAR) + port->ignore_status_mask |= AML_UART_PARITY_ERR | + AML_UART_FRAME_ERR; + + uart_update_timeout(port, termios->c_cflag, baud); + spin_unlock_irqrestore(&port->lock, flags); +} + +static int meson_uart_verify_port(struct uart_port *port, + struct serial_struct *ser) +{ + int ret = 0; + + if (port->type != PORT_MESON) + ret = -EINVAL; + if (port->irq != ser->irq) + ret = -EINVAL; + if (ser->baud_base < 9600) + ret = -EINVAL; + return ret; +} + +static void meson_uart_release_port(struct uart_port *port) +{ + devm_iounmap(port->dev, port->membase); + port->membase = NULL; + devm_release_mem_region(port->dev, port->mapbase, port->mapsize); +} + +static int meson_uart_request_port(struct uart_port *port) +{ + if (!devm_request_mem_region(port->dev, port->mapbase, port->mapsize, + dev_name(port->dev))) { + dev_err(port->dev, "Memory region busy\n"); + return -EBUSY; + } + + port->membase = devm_ioremap(port->dev, port->mapbase, + port->mapsize); + if (!port->membase) + return -ENOMEM; + + return 0; +} + +static void meson_uart_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) { + port->type = PORT_MESON; + meson_uart_request_port(port); + } +} + +#ifdef CONFIG_CONSOLE_POLL +/* + * Console polling routines for writing and reading from the uart while + * in an interrupt or debug context (i.e. kgdb). + */ + +static int meson_uart_poll_get_char(struct uart_port *port) +{ + u32 c; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + + if (readl(port->membase + AML_UART_STATUS) & AML_UART_RX_EMPTY) + c = NO_POLL_CHAR; + else + c = readl(port->membase + AML_UART_RFIFO); + + spin_unlock_irqrestore(&port->lock, flags); + + return c; +} + +static void meson_uart_poll_put_char(struct uart_port *port, unsigned char c) +{ + unsigned long flags; + u32 reg; + int ret; + + spin_lock_irqsave(&port->lock, flags); + + /* Wait until FIFO is empty or timeout */ + ret = readl_poll_timeout_atomic(port->membase + AML_UART_STATUS, reg, + reg & AML_UART_TX_EMPTY, + AML_UART_POLL_USEC, + AML_UART_TIMEOUT_USEC); + if (ret == -ETIMEDOUT) { + dev_err(port->dev, "Timeout waiting for UART TX EMPTY\n"); + goto out; + } + + /* Write the character */ + writel(c, port->membase + AML_UART_WFIFO); + + /* Wait until FIFO is empty or timeout */ + ret = readl_poll_timeout_atomic(port->membase + AML_UART_STATUS, reg, + reg & AML_UART_TX_EMPTY, + AML_UART_POLL_USEC, + AML_UART_TIMEOUT_USEC); + if (ret == -ETIMEDOUT) + dev_err(port->dev, "Timeout waiting for UART TX EMPTY\n"); + +out: + spin_unlock_irqrestore(&port->lock, flags); +} + +#endif /* CONFIG_CONSOLE_POLL */ + +static const struct uart_ops meson_uart_ops = { + .set_mctrl = meson_uart_set_mctrl, + .get_mctrl = meson_uart_get_mctrl, + .tx_empty = meson_uart_tx_empty, + .start_tx = meson_uart_start_tx, + .stop_tx = meson_uart_stop_tx, + .stop_rx = meson_uart_stop_rx, + .startup = meson_uart_startup, + .shutdown = meson_uart_shutdown, + .set_termios = meson_uart_set_termios, + .type = meson_uart_type, + .config_port = meson_uart_config_port, + .request_port = meson_uart_request_port, + .release_port = meson_uart_release_port, + .verify_port = meson_uart_verify_port, +#ifdef CONFIG_CONSOLE_POLL + .poll_get_char = meson_uart_poll_get_char, + .poll_put_char = meson_uart_poll_put_char, +#endif +}; + +#ifdef CONFIG_SERIAL_MESON_CONSOLE +static void meson_uart_enable_tx_engine(struct uart_port *port) +{ + u32 val; + + val = readl(port->membase + AML_UART_CONTROL); + val |= AML_UART_TX_EN; + writel(val, port->membase + AML_UART_CONTROL); +} + +static void meson_console_putchar(struct uart_port *port, unsigned char ch) +{ + if (!port->membase) + return; + + while (readl(port->membase + AML_UART_STATUS) & AML_UART_TX_FULL) + cpu_relax(); + writel(ch, port->membase + AML_UART_WFIFO); +} + +static void meson_serial_port_write(struct uart_port *port, const char *s, + u_int count) +{ + unsigned long flags; + int locked; + u32 val, tmp; + + local_irq_save(flags); + if (port->sysrq) { + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&port->lock); + } else { + spin_lock(&port->lock); + locked = 1; + } + + val = readl(port->membase + AML_UART_CONTROL); + tmp = val & ~(AML_UART_TX_INT_EN | AML_UART_RX_INT_EN); + writel(tmp, port->membase + AML_UART_CONTROL); + + uart_console_write(port, s, count, meson_console_putchar); + writel(val, port->membase + AML_UART_CONTROL); + + if (locked) + spin_unlock(&port->lock); + local_irq_restore(flags); +} + +static void meson_serial_console_write(struct console *co, const char *s, + u_int count) +{ + struct uart_port *port; + + port = meson_ports[co->index]; + if (!port) + return; + + meson_serial_port_write(port, s, count); +} + +static int meson_serial_console_setup(struct console *co, char *options) +{ + struct uart_port *port; + int baud = 115200; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (co->index < 0 || co->index >= AML_UART_PORT_NUM) + return -EINVAL; + + port = meson_ports[co->index]; + if (!port || !port->membase) + return -ENODEV; + + meson_uart_enable_tx_engine(port); + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct console meson_serial_console = { + .name = AML_UART_DEV_NAME, + .write = meson_serial_console_write, + .device = uart_console_device, + .setup = meson_serial_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &meson_uart_driver, +}; + +static int __init meson_serial_console_init(void) +{ + register_console(&meson_serial_console); + return 0; +} + +static void meson_serial_early_console_write(struct console *co, + const char *s, + u_int count) +{ + struct earlycon_device *dev = co->data; + + meson_serial_port_write(&dev->port, s, count); +} + +static int __init +meson_serial_early_console_setup(struct earlycon_device *device, const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + meson_uart_enable_tx_engine(&device->port); + device->con->write = meson_serial_early_console_write; + return 0; +} + +OF_EARLYCON_DECLARE(meson, "amlogic,meson-ao-uart", + meson_serial_early_console_setup); + +#define MESON_SERIAL_CONSOLE (&meson_serial_console) +#else +static int __init meson_serial_console_init(void) { + return 0; +} +#define MESON_SERIAL_CONSOLE NULL +#endif + +static struct uart_driver meson_uart_driver = { + .owner = THIS_MODULE, + .driver_name = "meson_uart", + .dev_name = AML_UART_DEV_NAME, + .nr = AML_UART_PORT_NUM, + .cons = MESON_SERIAL_CONSOLE, +}; + +static int meson_uart_probe_clocks(struct platform_device *pdev, + struct uart_port *port) +{ + struct clk *clk_xtal = NULL; + struct clk *clk_pclk = NULL; + struct clk *clk_baud = NULL; + + clk_pclk = devm_clk_get_enabled(&pdev->dev, "pclk"); + if (IS_ERR(clk_pclk)) + return PTR_ERR(clk_pclk); + + clk_xtal = devm_clk_get_enabled(&pdev->dev, "xtal"); + if (IS_ERR(clk_xtal)) + return PTR_ERR(clk_xtal); + + clk_baud = devm_clk_get_enabled(&pdev->dev, "baud"); + if (IS_ERR(clk_baud)) + return PTR_ERR(clk_baud); + + port->uartclk = clk_get_rate(clk_baud); + + return 0; +} + +static int meson_uart_probe(struct platform_device *pdev) +{ + struct resource *res_mem; + struct uart_port *port; + u32 fifosize = 64; /* Default is 64, 128 for EE UART_0 */ + int ret = 0; + int irq; + bool has_rtscts; + + if (pdev->dev.of_node) + pdev->id = of_alias_get_id(pdev->dev.of_node, "serial"); + + if (pdev->id < 0) { + int id; + + for (id = AML_UART_PORT_OFFSET; id < AML_UART_PORT_NUM; id++) { + if (!meson_ports[id]) { + pdev->id = id; + break; + } + } + } + + if (pdev->id < 0 || pdev->id >= AML_UART_PORT_NUM) + return -EINVAL; + + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res_mem) + return -ENODEV; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + of_property_read_u32(pdev->dev.of_node, "fifo-size", &fifosize); + has_rtscts = of_property_read_bool(pdev->dev.of_node, "uart-has-rtscts"); + + if (meson_ports[pdev->id]) { + dev_err(&pdev->dev, "port %d already allocated\n", pdev->id); + return -EBUSY; + } + + port = devm_kzalloc(&pdev->dev, sizeof(struct uart_port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + ret = meson_uart_probe_clocks(pdev, port); + if (ret) + return ret; + + port->iotype = UPIO_MEM; + port->mapbase = res_mem->start; + port->mapsize = resource_size(res_mem); + port->irq = irq; + port->flags = UPF_BOOT_AUTOCONF | UPF_LOW_LATENCY; + if (has_rtscts) + port->flags |= UPF_HARD_FLOW; + port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MESON_CONSOLE); + port->dev = &pdev->dev; + port->line = pdev->id; + port->type = PORT_MESON; + port->x_char = 0; + port->ops = &meson_uart_ops; + port->fifosize = fifosize; + port->private_data = (void *)device_get_match_data(&pdev->dev); + + meson_ports[pdev->id] = port; + platform_set_drvdata(pdev, port); + + /* reset port before registering (and possibly registering console) */ + if (meson_uart_request_port(port) >= 0) { + meson_uart_reset(port); + meson_uart_release_port(port); + } + + ret = uart_add_one_port(&meson_uart_driver, port); + if (ret) + meson_ports[pdev->id] = NULL; + + return ret; +} + +static int meson_uart_remove(struct platform_device *pdev) +{ + struct uart_port *port; + + port = platform_get_drvdata(pdev); + uart_remove_one_port(&meson_uart_driver, port); + meson_ports[pdev->id] = NULL; + + return 0; +} + +static struct meson_uart_data s4_uart_data = { + .has_xtal_div2 = true, +}; + +static const struct of_device_id meson_uart_dt_match[] = { + { .compatible = "amlogic,meson6-uart" }, + { .compatible = "amlogic,meson8-uart" }, + { .compatible = "amlogic,meson8b-uart" }, + { .compatible = "amlogic,meson-gx-uart" }, + { + .compatible = "amlogic,meson-s4-uart", + .data = (void *)&s4_uart_data, + }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, meson_uart_dt_match); + +static struct platform_driver meson_uart_platform_driver = { + .probe = meson_uart_probe, + .remove = meson_uart_remove, + .driver = { + .name = "meson_uart", + .of_match_table = meson_uart_dt_match, + }, +}; + +static int __init meson_uart_init(void) +{ + int ret; + + ret = meson_serial_console_init(); + if (ret) + return ret; + + ret = uart_register_driver(&meson_uart_driver); + if (ret) + return ret; + + ret = platform_driver_register(&meson_uart_platform_driver); + if (ret) + uart_unregister_driver(&meson_uart_driver); + + return ret; +} + +static void __exit meson_uart_exit(void) +{ + platform_driver_unregister(&meson_uart_platform_driver); + uart_unregister_driver(&meson_uart_driver); +} + +module_init(meson_uart_init); +module_exit(meson_uart_exit); + +MODULE_AUTHOR("Carlo Caione <carlo@caione.org>"); +MODULE_DESCRIPTION("Amlogic Meson serial port driver"); +MODULE_LICENSE("GPL v2"); |