// 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 #include #include #include #include #include #include #include #include #include #include #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 "); MODULE_DESCRIPTION("RDA8810PL serial device driver"); MODULE_LICENSE("GPL");