diff options
Diffstat (limited to 'drivers/tty/serial/rda-uart.c')
| -rw-r--r-- | drivers/tty/serial/rda-uart.c | 831 |
1 files changed, 831 insertions, 0 deletions
diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c new file mode 100644 index 000000000..a45069e7e --- /dev/null +++ b/drivers/tty/serial/rda-uart.c @@ -0,0 +1,831 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * RDA8810PL serial device driver + * + * Copyright RDA Microelectronics Company Limited + * Copyright (c) 2017 Andreas Färber + * Copyright (c) 2018 Manivannan Sadhasivam + */ + +#include <linux/clk.h> +#include <linux/console.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.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> + +#define RDA_UART_PORT_NUM 3 +#define RDA_UART_DEV_NAME "ttyRDA" + +#define RDA_UART_CTRL 0x00 +#define RDA_UART_STATUS 0x04 +#define RDA_UART_RXTX_BUFFER 0x08 +#define RDA_UART_IRQ_MASK 0x0c +#define RDA_UART_IRQ_CAUSE 0x10 +#define RDA_UART_IRQ_TRIGGERS 0x14 +#define RDA_UART_CMD_SET 0x18 +#define RDA_UART_CMD_CLR 0x1c + +/* UART_CTRL Bits */ +#define RDA_UART_ENABLE BIT(0) +#define RDA_UART_DBITS_8 BIT(1) +#define RDA_UART_TX_SBITS_2 BIT(2) +#define RDA_UART_PARITY_EN BIT(3) +#define RDA_UART_PARITY(x) (((x) & 0x3) << 4) +#define RDA_UART_PARITY_ODD RDA_UART_PARITY(0) +#define RDA_UART_PARITY_EVEN RDA_UART_PARITY(1) +#define RDA_UART_PARITY_SPACE RDA_UART_PARITY(2) +#define RDA_UART_PARITY_MARK RDA_UART_PARITY(3) +#define RDA_UART_DIV_MODE BIT(20) +#define RDA_UART_IRDA_EN BIT(21) +#define RDA_UART_DMA_EN BIT(22) +#define RDA_UART_FLOW_CNT_EN BIT(23) +#define RDA_UART_LOOP_BACK_EN BIT(24) +#define RDA_UART_RX_LOCK_ERR BIT(25) +#define RDA_UART_RX_BREAK_LEN(x) (((x) & 0xf) << 28) + +/* UART_STATUS Bits */ +#define RDA_UART_RX_FIFO(x) (((x) & 0x7f) << 0) +#define RDA_UART_RX_FIFO_MASK (0x7f << 0) +#define RDA_UART_TX_FIFO(x) (((x) & 0x1f) << 8) +#define RDA_UART_TX_FIFO_MASK (0x1f << 8) +#define RDA_UART_TX_ACTIVE BIT(14) +#define RDA_UART_RX_ACTIVE BIT(15) +#define RDA_UART_RX_OVERFLOW_ERR BIT(16) +#define RDA_UART_TX_OVERFLOW_ERR BIT(17) +#define RDA_UART_RX_PARITY_ERR BIT(18) +#define RDA_UART_RX_FRAMING_ERR BIT(19) +#define RDA_UART_RX_BREAK_INT BIT(20) +#define RDA_UART_DCTS BIT(24) +#define RDA_UART_CTS BIT(25) +#define RDA_UART_DTR BIT(28) +#define RDA_UART_CLK_ENABLED BIT(31) + +/* UART_RXTX_BUFFER Bits */ +#define RDA_UART_RX_DATA(x) (((x) & 0xff) << 0) +#define RDA_UART_TX_DATA(x) (((x) & 0xff) << 0) + +/* UART_IRQ_MASK Bits */ +#define RDA_UART_TX_MODEM_STATUS BIT(0) +#define RDA_UART_RX_DATA_AVAILABLE BIT(1) +#define RDA_UART_TX_DATA_NEEDED BIT(2) +#define RDA_UART_RX_TIMEOUT BIT(3) +#define RDA_UART_RX_LINE_ERR BIT(4) +#define RDA_UART_TX_DMA_DONE BIT(5) +#define RDA_UART_RX_DMA_DONE BIT(6) +#define RDA_UART_RX_DMA_TIMEOUT BIT(7) +#define RDA_UART_DTR_RISE BIT(8) +#define RDA_UART_DTR_FALL BIT(9) + +/* UART_IRQ_CAUSE Bits */ +#define RDA_UART_TX_MODEM_STATUS_U BIT(16) +#define RDA_UART_RX_DATA_AVAILABLE_U BIT(17) +#define RDA_UART_TX_DATA_NEEDED_U BIT(18) +#define RDA_UART_RX_TIMEOUT_U BIT(19) +#define RDA_UART_RX_LINE_ERR_U BIT(20) +#define RDA_UART_TX_DMA_DONE_U BIT(21) +#define RDA_UART_RX_DMA_DONE_U BIT(22) +#define RDA_UART_RX_DMA_TIMEOUT_U BIT(23) +#define RDA_UART_DTR_RISE_U BIT(24) +#define RDA_UART_DTR_FALL_U BIT(25) + +/* UART_TRIGGERS Bits */ +#define RDA_UART_RX_TRIGGER(x) (((x) & 0x1f) << 0) +#define RDA_UART_TX_TRIGGER(x) (((x) & 0xf) << 8) +#define RDA_UART_AFC_LEVEL(x) (((x) & 0x1f) << 16) + +/* UART_CMD_SET Bits */ +#define RDA_UART_RI BIT(0) +#define RDA_UART_DCD BIT(1) +#define RDA_UART_DSR BIT(2) +#define RDA_UART_TX_BREAK_CONTROL BIT(3) +#define RDA_UART_TX_FINISH_N_WAIT BIT(4) +#define RDA_UART_RTS BIT(5) +#define RDA_UART_RX_FIFO_RESET BIT(6) +#define RDA_UART_TX_FIFO_RESET BIT(7) + +#define RDA_UART_TX_FIFO_SIZE 16 + +static struct uart_driver rda_uart_driver; + +struct rda_uart_port { + struct uart_port port; + struct clk *clk; +}; + +#define to_rda_uart_port(port) container_of(port, struct rda_uart_port, port) + +static struct rda_uart_port *rda_uart_ports[RDA_UART_PORT_NUM]; + +static inline void rda_uart_write(struct uart_port *port, u32 val, + unsigned int off) +{ + writel(val, port->membase + off); +} + +static inline u32 rda_uart_read(struct uart_port *port, unsigned int off) +{ + return readl(port->membase + off); +} + +static unsigned int rda_uart_tx_empty(struct uart_port *port) +{ + unsigned long flags; + unsigned int ret; + u32 val; + + spin_lock_irqsave(&port->lock, flags); + + val = rda_uart_read(port, RDA_UART_STATUS); + ret = (val & RDA_UART_TX_FIFO_MASK) ? TIOCSER_TEMT : 0; + + spin_unlock_irqrestore(&port->lock, flags); + + return ret; +} + +static unsigned int rda_uart_get_mctrl(struct uart_port *port) +{ + unsigned int mctrl = 0; + u32 cmd_set, status; + + cmd_set = rda_uart_read(port, RDA_UART_CMD_SET); + status = rda_uart_read(port, RDA_UART_STATUS); + if (cmd_set & RDA_UART_RTS) + mctrl |= TIOCM_RTS; + if (!(status & RDA_UART_CTS)) + mctrl |= TIOCM_CTS; + + return mctrl; +} + +static void rda_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + u32 val; + + if (mctrl & TIOCM_RTS) { + val = rda_uart_read(port, RDA_UART_CMD_SET); + rda_uart_write(port, (val | RDA_UART_RTS), RDA_UART_CMD_SET); + } else { + /* Clear RTS to stop to receive. */ + val = rda_uart_read(port, RDA_UART_CMD_CLR); + rda_uart_write(port, (val | RDA_UART_RTS), RDA_UART_CMD_CLR); + } + + val = rda_uart_read(port, RDA_UART_CTRL); + + if (mctrl & TIOCM_LOOP) + val |= RDA_UART_LOOP_BACK_EN; + else + val &= ~RDA_UART_LOOP_BACK_EN; + + rda_uart_write(port, val, RDA_UART_CTRL); +} + +static void rda_uart_stop_tx(struct uart_port *port) +{ + u32 val; + + val = rda_uart_read(port, RDA_UART_IRQ_MASK); + val &= ~RDA_UART_TX_DATA_NEEDED; + rda_uart_write(port, val, RDA_UART_IRQ_MASK); + + val = rda_uart_read(port, RDA_UART_CMD_SET); + val |= RDA_UART_TX_FIFO_RESET; + rda_uart_write(port, val, RDA_UART_CMD_SET); +} + +static void rda_uart_stop_rx(struct uart_port *port) +{ + u32 val; + + val = rda_uart_read(port, RDA_UART_IRQ_MASK); + val &= ~(RDA_UART_RX_DATA_AVAILABLE | RDA_UART_RX_TIMEOUT); + rda_uart_write(port, val, RDA_UART_IRQ_MASK); + + /* Read Rx buffer before reset to avoid Rx timeout interrupt */ + val = rda_uart_read(port, RDA_UART_RXTX_BUFFER); + + val = rda_uart_read(port, RDA_UART_CMD_SET); + val |= RDA_UART_RX_FIFO_RESET; + rda_uart_write(port, val, RDA_UART_CMD_SET); +} + +static void rda_uart_start_tx(struct uart_port *port) +{ + u32 val; + + if (uart_tx_stopped(port)) { + rda_uart_stop_tx(port); + return; + } + + val = rda_uart_read(port, RDA_UART_IRQ_MASK); + val |= RDA_UART_TX_DATA_NEEDED; + rda_uart_write(port, val, RDA_UART_IRQ_MASK); +} + +static void rda_uart_change_baudrate(struct rda_uart_port *rda_port, + unsigned long baud) +{ + clk_set_rate(rda_port->clk, baud * 8); +} + +static void rda_uart_set_termios(struct uart_port *port, + struct ktermios *termios, + struct ktermios *old) +{ + struct rda_uart_port *rda_port = to_rda_uart_port(port); + unsigned long flags; + unsigned int ctrl, cmd_set, cmd_clr, triggers; + unsigned int baud; + u32 irq_mask; + + spin_lock_irqsave(&port->lock, flags); + + baud = uart_get_baud_rate(port, termios, old, 9600, port->uartclk / 4); + rda_uart_change_baudrate(rda_port, baud); + + ctrl = rda_uart_read(port, RDA_UART_CTRL); + cmd_set = rda_uart_read(port, RDA_UART_CMD_SET); + cmd_clr = rda_uart_read(port, RDA_UART_CMD_CLR); + + switch (termios->c_cflag & CSIZE) { + case CS5: + case CS6: + dev_warn(port->dev, "bit size not supported, using 7 bits\n"); + fallthrough; + case CS7: + ctrl &= ~RDA_UART_DBITS_8; + termios->c_cflag &= ~CSIZE; + termios->c_cflag |= CS7; + break; + default: + ctrl |= RDA_UART_DBITS_8; + break; + } + + /* stop bits */ + if (termios->c_cflag & CSTOPB) + ctrl |= RDA_UART_TX_SBITS_2; + else + ctrl &= ~RDA_UART_TX_SBITS_2; + + /* parity check */ + if (termios->c_cflag & PARENB) { + ctrl |= RDA_UART_PARITY_EN; + + /* Mark or Space parity */ + if (termios->c_cflag & CMSPAR) { + if (termios->c_cflag & PARODD) + ctrl |= RDA_UART_PARITY_MARK; + else + ctrl |= RDA_UART_PARITY_SPACE; + } else if (termios->c_cflag & PARODD) { + ctrl |= RDA_UART_PARITY_ODD; + } else { + ctrl |= RDA_UART_PARITY_EVEN; + } + } else { + ctrl &= ~RDA_UART_PARITY_EN; + } + + /* Hardware handshake (RTS/CTS) */ + if (termios->c_cflag & CRTSCTS) { + ctrl |= RDA_UART_FLOW_CNT_EN; + cmd_set |= RDA_UART_RTS; + } else { + ctrl &= ~RDA_UART_FLOW_CNT_EN; + cmd_clr |= RDA_UART_RTS; + } + + ctrl |= RDA_UART_ENABLE; + ctrl &= ~RDA_UART_DMA_EN; + + triggers = (RDA_UART_AFC_LEVEL(20) | RDA_UART_RX_TRIGGER(16)); + irq_mask = rda_uart_read(port, RDA_UART_IRQ_MASK); + rda_uart_write(port, 0, RDA_UART_IRQ_MASK); + + rda_uart_write(port, triggers, RDA_UART_IRQ_TRIGGERS); + rda_uart_write(port, ctrl, RDA_UART_CTRL); + rda_uart_write(port, cmd_set, RDA_UART_CMD_SET); + rda_uart_write(port, cmd_clr, RDA_UART_CMD_CLR); + + rda_uart_write(port, irq_mask, RDA_UART_IRQ_MASK); + + /* Don't rewrite B0 */ + if (tty_termios_baud_rate(termios)) + tty_termios_encode_baud_rate(termios, baud, baud); + + /* update the per-port timeout */ + uart_update_timeout(port, termios->c_cflag, baud); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static void rda_uart_send_chars(struct uart_port *port) +{ + struct circ_buf *xmit = &port->state->xmit; + unsigned int ch; + u32 val; + + if (uart_tx_stopped(port)) + return; + + if (port->x_char) { + while (!(rda_uart_read(port, RDA_UART_STATUS) & + RDA_UART_TX_FIFO_MASK)) + cpu_relax(); + + rda_uart_write(port, port->x_char, RDA_UART_RXTX_BUFFER); + port->icount.tx++; + port->x_char = 0; + } + + while (rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_TX_FIFO_MASK) { + if (uart_circ_empty(xmit)) + break; + + ch = xmit->buf[xmit->tail]; + rda_uart_write(port, ch, RDA_UART_RXTX_BUFFER); + xmit->tail = (xmit->tail + 1) & (SERIAL_XMIT_SIZE - 1); + port->icount.tx++; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (!uart_circ_empty(xmit)) { + /* Re-enable Tx FIFO interrupt */ + val = rda_uart_read(port, RDA_UART_IRQ_MASK); + val |= RDA_UART_TX_DATA_NEEDED; + rda_uart_write(port, val, RDA_UART_IRQ_MASK); + } +} + +static void rda_uart_receive_chars(struct uart_port *port) +{ + u32 status, val; + + status = rda_uart_read(port, RDA_UART_STATUS); + while ((status & RDA_UART_RX_FIFO_MASK)) { + char flag = TTY_NORMAL; + + if (status & RDA_UART_RX_PARITY_ERR) { + port->icount.parity++; + flag = TTY_PARITY; + } + + if (status & RDA_UART_RX_FRAMING_ERR) { + port->icount.frame++; + flag = TTY_FRAME; + } + + if (status & RDA_UART_RX_OVERFLOW_ERR) { + port->icount.overrun++; + flag = TTY_OVERRUN; + } + + val = rda_uart_read(port, RDA_UART_RXTX_BUFFER); + val &= 0xff; + + port->icount.rx++; + tty_insert_flip_char(&port->state->port, val, flag); + + status = rda_uart_read(port, RDA_UART_STATUS); + } + + spin_unlock(&port->lock); + tty_flip_buffer_push(&port->state->port); + spin_lock(&port->lock); +} + +static irqreturn_t rda_interrupt(int irq, void *dev_id) +{ + struct uart_port *port = dev_id; + unsigned long flags; + u32 val, irq_mask; + + spin_lock_irqsave(&port->lock, flags); + + /* Clear IRQ cause */ + val = rda_uart_read(port, RDA_UART_IRQ_CAUSE); + rda_uart_write(port, val, RDA_UART_IRQ_CAUSE); + + if (val & (RDA_UART_RX_DATA_AVAILABLE | RDA_UART_RX_TIMEOUT)) + rda_uart_receive_chars(port); + + if (val & (RDA_UART_TX_DATA_NEEDED)) { + irq_mask = rda_uart_read(port, RDA_UART_IRQ_MASK); + irq_mask &= ~RDA_UART_TX_DATA_NEEDED; + rda_uart_write(port, irq_mask, RDA_UART_IRQ_MASK); + + rda_uart_send_chars(port); + } + + spin_unlock_irqrestore(&port->lock, flags); + + return IRQ_HANDLED; +} + +static int rda_uart_startup(struct uart_port *port) +{ + unsigned long flags; + int ret; + u32 val; + + spin_lock_irqsave(&port->lock, flags); + rda_uart_write(port, 0, RDA_UART_IRQ_MASK); + spin_unlock_irqrestore(&port->lock, flags); + + ret = request_irq(port->irq, rda_interrupt, IRQF_NO_SUSPEND, + "rda-uart", port); + if (ret) + return ret; + + spin_lock_irqsave(&port->lock, flags); + + val = rda_uart_read(port, RDA_UART_CTRL); + val |= RDA_UART_ENABLE; + rda_uart_write(port, val, RDA_UART_CTRL); + + /* enable rx interrupt */ + val = rda_uart_read(port, RDA_UART_IRQ_MASK); + val |= (RDA_UART_RX_DATA_AVAILABLE | RDA_UART_RX_TIMEOUT); + rda_uart_write(port, val, RDA_UART_IRQ_MASK); + + spin_unlock_irqrestore(&port->lock, flags); + + return 0; +} + +static void rda_uart_shutdown(struct uart_port *port) +{ + unsigned long flags; + u32 val; + + spin_lock_irqsave(&port->lock, flags); + + rda_uart_stop_tx(port); + rda_uart_stop_rx(port); + + val = rda_uart_read(port, RDA_UART_CTRL); + val &= ~RDA_UART_ENABLE; + rda_uart_write(port, val, RDA_UART_CTRL); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static const char *rda_uart_type(struct uart_port *port) +{ + return (port->type == PORT_RDA) ? "rda-uart" : NULL; +} + +static int rda_uart_request_port(struct uart_port *port) +{ + struct platform_device *pdev = to_platform_device(port->dev); + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENXIO; + + if (!devm_request_mem_region(port->dev, port->mapbase, + resource_size(res), dev_name(port->dev))) + return -EBUSY; + + if (port->flags & UPF_IOREMAP) { + port->membase = devm_ioremap(port->dev, port->mapbase, + resource_size(res)); + if (!port->membase) + return -EBUSY; + } + + return 0; +} + +static void rda_uart_config_port(struct uart_port *port, int flags) +{ + unsigned long irq_flags; + + if (flags & UART_CONFIG_TYPE) { + port->type = PORT_RDA; + rda_uart_request_port(port); + } + + spin_lock_irqsave(&port->lock, irq_flags); + + /* Clear mask, so no surprise interrupts. */ + rda_uart_write(port, 0, RDA_UART_IRQ_MASK); + + /* Clear status register */ + rda_uart_write(port, 0, RDA_UART_STATUS); + + spin_unlock_irqrestore(&port->lock, irq_flags); +} + +static void rda_uart_release_port(struct uart_port *port) +{ + struct platform_device *pdev = to_platform_device(port->dev); + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return; + + if (port->flags & UPF_IOREMAP) { + devm_release_mem_region(port->dev, port->mapbase, + resource_size(res)); + devm_iounmap(port->dev, port->membase); + port->membase = NULL; + } +} + +static int rda_uart_verify_port(struct uart_port *port, + struct serial_struct *ser) +{ + if (port->type != PORT_RDA) + return -EINVAL; + + if (port->irq != ser->irq) + return -EINVAL; + + return 0; +} + +static const struct uart_ops rda_uart_ops = { + .tx_empty = rda_uart_tx_empty, + .get_mctrl = rda_uart_get_mctrl, + .set_mctrl = rda_uart_set_mctrl, + .start_tx = rda_uart_start_tx, + .stop_tx = rda_uart_stop_tx, + .stop_rx = rda_uart_stop_rx, + .startup = rda_uart_startup, + .shutdown = rda_uart_shutdown, + .set_termios = rda_uart_set_termios, + .type = rda_uart_type, + .request_port = rda_uart_request_port, + .release_port = rda_uart_release_port, + .config_port = rda_uart_config_port, + .verify_port = rda_uart_verify_port, +}; + +#ifdef CONFIG_SERIAL_RDA_CONSOLE + +static void rda_console_putchar(struct uart_port *port, int ch) +{ + if (!port->membase) + return; + + while (!(rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_TX_FIFO_MASK)) + cpu_relax(); + + rda_uart_write(port, ch, RDA_UART_RXTX_BUFFER); +} + +static void rda_uart_port_write(struct uart_port *port, const char *s, + u_int count) +{ + u32 old_irq_mask; + unsigned long flags; + int locked; + + 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; + } + + old_irq_mask = rda_uart_read(port, RDA_UART_IRQ_MASK); + rda_uart_write(port, 0, RDA_UART_IRQ_MASK); + + uart_console_write(port, s, count, rda_console_putchar); + + /* wait until all contents have been sent out */ + while (!(rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_TX_FIFO_MASK)) + cpu_relax(); + + rda_uart_write(port, old_irq_mask, RDA_UART_IRQ_MASK); + + if (locked) + spin_unlock(&port->lock); + + local_irq_restore(flags); +} + +static void rda_uart_console_write(struct console *co, const char *s, + u_int count) +{ + struct rda_uart_port *rda_port; + + rda_port = rda_uart_ports[co->index]; + if (!rda_port) + return; + + rda_uart_port_write(&rda_port->port, s, count); +} + +static int rda_uart_console_setup(struct console *co, char *options) +{ + struct rda_uart_port *rda_port; + int baud = 921600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (co->index < 0 || co->index >= RDA_UART_PORT_NUM) + return -EINVAL; + + rda_port = rda_uart_ports[co->index]; + if (!rda_port || !rda_port->port.membase) + return -ENODEV; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(&rda_port->port, co, baud, parity, bits, flow); +} + +static struct console rda_uart_console = { + .name = RDA_UART_DEV_NAME, + .write = rda_uart_console_write, + .device = uart_console_device, + .setup = rda_uart_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &rda_uart_driver, +}; + +static int __init rda_uart_console_init(void) +{ + register_console(&rda_uart_console); + + return 0; +} +console_initcall(rda_uart_console_init); + +static void rda_uart_early_console_write(struct console *co, + const char *s, + u_int count) +{ + struct earlycon_device *dev = co->data; + + rda_uart_port_write(&dev->port, s, count); +} + +static int __init +rda_uart_early_console_setup(struct earlycon_device *device, const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = rda_uart_early_console_write; + + return 0; +} + +OF_EARLYCON_DECLARE(rda, "rda,8810pl-uart", + rda_uart_early_console_setup); + +#define RDA_UART_CONSOLE (&rda_uart_console) +#else +#define RDA_UART_CONSOLE NULL +#endif /* CONFIG_SERIAL_RDA_CONSOLE */ + +static struct uart_driver rda_uart_driver = { + .owner = THIS_MODULE, + .driver_name = "rda-uart", + .dev_name = RDA_UART_DEV_NAME, + .nr = RDA_UART_PORT_NUM, + .cons = RDA_UART_CONSOLE, +}; + +static const struct of_device_id rda_uart_dt_matches[] = { + { .compatible = "rda,8810pl-uart" }, + { } +}; +MODULE_DEVICE_TABLE(of, rda_uart_dt_matches); + +static int rda_uart_probe(struct platform_device *pdev) +{ + struct resource *res_mem; + struct rda_uart_port *rda_port; + int ret, irq; + + if (pdev->dev.of_node) + pdev->id = of_alias_get_id(pdev->dev.of_node, "serial"); + + if (pdev->id < 0 || pdev->id >= RDA_UART_PORT_NUM) { + dev_err(&pdev->dev, "id %d out of range\n", pdev->id); + return -EINVAL; + } + + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res_mem) { + dev_err(&pdev->dev, "could not get mem\n"); + return -ENODEV; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + if (rda_uart_ports[pdev->id]) { + dev_err(&pdev->dev, "port %d already allocated\n", pdev->id); + return -EBUSY; + } + + rda_port = devm_kzalloc(&pdev->dev, sizeof(*rda_port), GFP_KERNEL); + if (!rda_port) + return -ENOMEM; + + rda_port->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(rda_port->clk)) { + dev_err(&pdev->dev, "could not get clk\n"); + return PTR_ERR(rda_port->clk); + } + + rda_port->port.dev = &pdev->dev; + rda_port->port.regshift = 0; + rda_port->port.line = pdev->id; + rda_port->port.type = PORT_RDA; + rda_port->port.iotype = UPIO_MEM; + rda_port->port.mapbase = res_mem->start; + rda_port->port.irq = irq; + rda_port->port.uartclk = clk_get_rate(rda_port->clk); + if (rda_port->port.uartclk == 0) { + dev_err(&pdev->dev, "clock rate is zero\n"); + return -EINVAL; + } + rda_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP | + UPF_LOW_LATENCY; + rda_port->port.x_char = 0; + rda_port->port.fifosize = RDA_UART_TX_FIFO_SIZE; + rda_port->port.ops = &rda_uart_ops; + + rda_uart_ports[pdev->id] = rda_port; + platform_set_drvdata(pdev, rda_port); + + ret = uart_add_one_port(&rda_uart_driver, &rda_port->port); + if (ret) + rda_uart_ports[pdev->id] = NULL; + + return ret; +} + +static int rda_uart_remove(struct platform_device *pdev) +{ + struct rda_uart_port *rda_port = platform_get_drvdata(pdev); + + uart_remove_one_port(&rda_uart_driver, &rda_port->port); + rda_uart_ports[pdev->id] = NULL; + + return 0; +} + +static struct platform_driver rda_uart_platform_driver = { + .probe = rda_uart_probe, + .remove = rda_uart_remove, + .driver = { + .name = "rda-uart", + .of_match_table = rda_uart_dt_matches, + }, +}; + +static int __init rda_uart_init(void) +{ + int ret; + + ret = uart_register_driver(&rda_uart_driver); + if (ret) + return ret; + + ret = platform_driver_register(&rda_uart_platform_driver); + if (ret) + uart_unregister_driver(&rda_uart_driver); + + return ret; +} + +static void __exit rda_uart_exit(void) +{ + platform_driver_unregister(&rda_uart_platform_driver); + uart_unregister_driver(&rda_uart_driver); +} + +module_init(rda_uart_init); +module_exit(rda_uart_exit); + +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); +MODULE_DESCRIPTION("RDA8810PL serial device driver"); +MODULE_LICENSE("GPL"); |