diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/tty/serial/bcm63xx_uart.c | 921 |
1 files changed, 921 insertions, 0 deletions
diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c new file mode 100644 index 000000000..5d9737c2d --- /dev/null +++ b/drivers/tty/serial/bcm63xx_uart.c @@ -0,0 +1,921 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Derived from many drivers using generic_serial interface. + * + * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr> + * + * Serial driver for BCM63xx integrated UART. + * + * Hardware flow control was _not_ tested since I only have RX/TX on + * my board. + */ + +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/console.h> +#include <linux/clk.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/sysrq.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/serial_bcm63xx.h> +#include <linux/io.h> +#include <linux/of.h> + +#define BCM63XX_NR_UARTS 2 + +static struct uart_port ports[BCM63XX_NR_UARTS]; + +/* + * rx interrupt mask / stat + * + * mask: + * - rx fifo full + * - rx fifo above threshold + * - rx fifo not empty for too long + */ +#define UART_RX_INT_MASK (UART_IR_MASK(UART_IR_RXOVER) | \ + UART_IR_MASK(UART_IR_RXTHRESH) | \ + UART_IR_MASK(UART_IR_RXTIMEOUT)) + +#define UART_RX_INT_STAT (UART_IR_STAT(UART_IR_RXOVER) | \ + UART_IR_STAT(UART_IR_RXTHRESH) | \ + UART_IR_STAT(UART_IR_RXTIMEOUT)) + +/* + * tx interrupt mask / stat + * + * mask: + * - tx fifo empty + * - tx fifo below threshold + */ +#define UART_TX_INT_MASK (UART_IR_MASK(UART_IR_TXEMPTY) | \ + UART_IR_MASK(UART_IR_TXTRESH)) + +#define UART_TX_INT_STAT (UART_IR_STAT(UART_IR_TXEMPTY) | \ + UART_IR_STAT(UART_IR_TXTRESH)) + +/* + * external input interrupt + * + * mask: any edge on CTS, DCD + */ +#define UART_EXTINP_INT_MASK (UART_EXTINP_IRMASK(UART_EXTINP_IR_CTS) | \ + UART_EXTINP_IRMASK(UART_EXTINP_IR_DCD)) + +/* + * handy uart register accessor + */ +static inline unsigned int bcm_uart_readl(struct uart_port *port, + unsigned int offset) +{ + return __raw_readl(port->membase + offset); +} + +static inline void bcm_uart_writel(struct uart_port *port, + unsigned int value, unsigned int offset) +{ + __raw_writel(value, port->membase + offset); +} + +/* + * serial core request to check if uart tx fifo is empty + */ +static unsigned int bcm_uart_tx_empty(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_IR_REG); + return (val & UART_IR_STAT(UART_IR_TXEMPTY)) ? 1 : 0; +} + +/* + * serial core request to set RTS and DTR pin state and loopback mode + */ +static void bcm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_MCTL_REG); + val &= ~(UART_MCTL_DTR_MASK | UART_MCTL_RTS_MASK); + /* invert of written value is reflected on the pin */ + if (!(mctrl & TIOCM_DTR)) + val |= UART_MCTL_DTR_MASK; + if (!(mctrl & TIOCM_RTS)) + val |= UART_MCTL_RTS_MASK; + bcm_uart_writel(port, val, UART_MCTL_REG); + + val = bcm_uart_readl(port, UART_CTL_REG); + if (mctrl & TIOCM_LOOP) + val |= UART_CTL_LOOPBACK_MASK; + else + val &= ~UART_CTL_LOOPBACK_MASK; + bcm_uart_writel(port, val, UART_CTL_REG); +} + +/* + * serial core request to return RI, CTS, DCD and DSR pin state + */ +static unsigned int bcm_uart_get_mctrl(struct uart_port *port) +{ + unsigned int val, mctrl; + + mctrl = 0; + val = bcm_uart_readl(port, UART_EXTINP_REG); + if (val & UART_EXTINP_RI_MASK) + mctrl |= TIOCM_RI; + if (val & UART_EXTINP_CTS_MASK) + mctrl |= TIOCM_CTS; + if (val & UART_EXTINP_DCD_MASK) + mctrl |= TIOCM_CD; + if (val & UART_EXTINP_DSR_MASK) + mctrl |= TIOCM_DSR; + return mctrl; +} + +/* + * serial core request to disable tx ASAP (used for flow control) + */ +static void bcm_uart_stop_tx(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_CTL_REG); + val &= ~(UART_CTL_TXEN_MASK); + bcm_uart_writel(port, val, UART_CTL_REG); + + val = bcm_uart_readl(port, UART_IR_REG); + val &= ~UART_TX_INT_MASK; + bcm_uart_writel(port, val, UART_IR_REG); +} + +/* + * serial core request to (re)enable tx + */ +static void bcm_uart_start_tx(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_IR_REG); + val |= UART_TX_INT_MASK; + bcm_uart_writel(port, val, UART_IR_REG); + + val = bcm_uart_readl(port, UART_CTL_REG); + val |= UART_CTL_TXEN_MASK; + bcm_uart_writel(port, val, UART_CTL_REG); +} + +/* + * serial core request to stop rx, called before port shutdown + */ +static void bcm_uart_stop_rx(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_IR_REG); + val &= ~UART_RX_INT_MASK; + bcm_uart_writel(port, val, UART_IR_REG); +} + +/* + * serial core request to enable modem status interrupt reporting + */ +static void bcm_uart_enable_ms(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_IR_REG); + val |= UART_IR_MASK(UART_IR_EXTIP); + bcm_uart_writel(port, val, UART_IR_REG); +} + +/* + * serial core request to start/stop emitting break char + */ +static void bcm_uart_break_ctl(struct uart_port *port, int ctl) +{ + unsigned long flags; + unsigned int val; + + spin_lock_irqsave(&port->lock, flags); + + val = bcm_uart_readl(port, UART_CTL_REG); + if (ctl) + val |= UART_CTL_XMITBRK_MASK; + else + val &= ~UART_CTL_XMITBRK_MASK; + bcm_uart_writel(port, val, UART_CTL_REG); + + spin_unlock_irqrestore(&port->lock, flags); +} + +/* + * return port type in string format + */ +static const char *bcm_uart_type(struct uart_port *port) +{ + return (port->type == PORT_BCM63XX) ? "bcm63xx_uart" : NULL; +} + +/* + * read all chars in rx fifo and send them to core + */ +static void bcm_uart_do_rx(struct uart_port *port) +{ + struct tty_port *tty_port = &port->state->port; + unsigned int max_count; + + /* limit number of char read in interrupt, should not be + * higher than fifo size anyway since we're much faster than + * serial port */ + max_count = 32; + do { + unsigned int iestat, c, cstat; + char flag; + + /* get overrun/fifo empty information from ier + * register */ + iestat = bcm_uart_readl(port, UART_IR_REG); + + if (unlikely(iestat & UART_IR_STAT(UART_IR_RXOVER))) { + unsigned int val; + + /* fifo reset is required to clear + * interrupt */ + val = bcm_uart_readl(port, UART_CTL_REG); + val |= UART_CTL_RSTRXFIFO_MASK; + bcm_uart_writel(port, val, UART_CTL_REG); + + port->icount.overrun++; + tty_insert_flip_char(tty_port, 0, TTY_OVERRUN); + } + + if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY))) + break; + + cstat = c = bcm_uart_readl(port, UART_FIFO_REG); + port->icount.rx++; + flag = TTY_NORMAL; + c &= 0xff; + + if (unlikely((cstat & UART_FIFO_ANYERR_MASK))) { + /* do stats first */ + if (cstat & UART_FIFO_BRKDET_MASK) { + port->icount.brk++; + if (uart_handle_break(port)) + continue; + } + + if (cstat & UART_FIFO_PARERR_MASK) + port->icount.parity++; + if (cstat & UART_FIFO_FRAMEERR_MASK) + port->icount.frame++; + + /* update flag wrt read_status_mask */ + cstat &= port->read_status_mask; + if (cstat & UART_FIFO_BRKDET_MASK) + flag = TTY_BREAK; + if (cstat & UART_FIFO_FRAMEERR_MASK) + flag = TTY_FRAME; + if (cstat & UART_FIFO_PARERR_MASK) + flag = TTY_PARITY; + } + + if (uart_handle_sysrq_char(port, c)) + continue; + + + if ((cstat & port->ignore_status_mask) == 0) + tty_insert_flip_char(tty_port, c, flag); + + } while (--max_count); + + tty_flip_buffer_push(tty_port); +} + +/* + * fill tx fifo with chars to send, stop when fifo is about to be full + * or when all chars have been sent. + */ +static void bcm_uart_do_tx(struct uart_port *port) +{ + struct circ_buf *xmit; + unsigned int val, max_count; + + if (port->x_char) { + bcm_uart_writel(port, port->x_char, UART_FIFO_REG); + port->icount.tx++; + port->x_char = 0; + return; + } + + if (uart_tx_stopped(port)) { + bcm_uart_stop_tx(port); + return; + } + + xmit = &port->state->xmit; + if (uart_circ_empty(xmit)) + goto txq_empty; + + val = bcm_uart_readl(port, UART_MCTL_REG); + val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT; + max_count = port->fifosize - val; + + while (max_count--) { + unsigned int c; + + c = xmit->buf[xmit->tail]; + bcm_uart_writel(port, c, UART_FIFO_REG); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + if (uart_circ_empty(xmit)) + break; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + + if (uart_circ_empty(xmit)) + goto txq_empty; + return; + +txq_empty: + /* nothing to send, disable transmit interrupt */ + val = bcm_uart_readl(port, UART_IR_REG); + val &= ~UART_TX_INT_MASK; + bcm_uart_writel(port, val, UART_IR_REG); + return; +} + +/* + * process uart interrupt + */ +static irqreturn_t bcm_uart_interrupt(int irq, void *dev_id) +{ + struct uart_port *port; + unsigned int irqstat; + + port = dev_id; + spin_lock(&port->lock); + + irqstat = bcm_uart_readl(port, UART_IR_REG); + if (irqstat & UART_RX_INT_STAT) + bcm_uart_do_rx(port); + + if (irqstat & UART_TX_INT_STAT) + bcm_uart_do_tx(port); + + if (irqstat & UART_IR_MASK(UART_IR_EXTIP)) { + unsigned int estat; + + estat = bcm_uart_readl(port, UART_EXTINP_REG); + if (estat & UART_EXTINP_IRSTAT(UART_EXTINP_IR_CTS)) + uart_handle_cts_change(port, + estat & UART_EXTINP_CTS_MASK); + if (estat & UART_EXTINP_IRSTAT(UART_EXTINP_IR_DCD)) + uart_handle_dcd_change(port, + estat & UART_EXTINP_DCD_MASK); + } + + spin_unlock(&port->lock); + return IRQ_HANDLED; +} + +/* + * enable rx & tx operation on uart + */ +static void bcm_uart_enable(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_CTL_REG); + val |= (UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK | UART_CTL_RXEN_MASK); + bcm_uart_writel(port, val, UART_CTL_REG); +} + +/* + * disable rx & tx operation on uart + */ +static void bcm_uart_disable(struct uart_port *port) +{ + unsigned int val; + + val = bcm_uart_readl(port, UART_CTL_REG); + val &= ~(UART_CTL_BRGEN_MASK | UART_CTL_TXEN_MASK | + UART_CTL_RXEN_MASK); + bcm_uart_writel(port, val, UART_CTL_REG); +} + +/* + * clear all unread data in rx fifo and unsent data in tx fifo + */ +static void bcm_uart_flush(struct uart_port *port) +{ + unsigned int val; + + /* empty rx and tx fifo */ + val = bcm_uart_readl(port, UART_CTL_REG); + val |= UART_CTL_RSTRXFIFO_MASK | UART_CTL_RSTTXFIFO_MASK; + bcm_uart_writel(port, val, UART_CTL_REG); + + /* read any pending char to make sure all irq status are + * cleared */ + (void)bcm_uart_readl(port, UART_FIFO_REG); +} + +/* + * serial core request to initialize uart and start rx operation + */ +static int bcm_uart_startup(struct uart_port *port) +{ + unsigned int val; + int ret; + + /* mask all irq and flush port */ + bcm_uart_disable(port); + bcm_uart_writel(port, 0, UART_IR_REG); + bcm_uart_flush(port); + + /* clear any pending external input interrupt */ + (void)bcm_uart_readl(port, UART_EXTINP_REG); + + /* set rx/tx fifo thresh to fifo half size */ + val = bcm_uart_readl(port, UART_MCTL_REG); + val &= ~(UART_MCTL_RXFIFOTHRESH_MASK | UART_MCTL_TXFIFOTHRESH_MASK); + val |= (port->fifosize / 2) << UART_MCTL_RXFIFOTHRESH_SHIFT; + val |= (port->fifosize / 2) << UART_MCTL_TXFIFOTHRESH_SHIFT; + bcm_uart_writel(port, val, UART_MCTL_REG); + + /* set rx fifo timeout to 1 char time */ + val = bcm_uart_readl(port, UART_CTL_REG); + val &= ~UART_CTL_RXTMOUTCNT_MASK; + val |= 1 << UART_CTL_RXTMOUTCNT_SHIFT; + bcm_uart_writel(port, val, UART_CTL_REG); + + /* report any edge on dcd and cts */ + val = UART_EXTINP_INT_MASK; + val |= UART_EXTINP_DCD_NOSENSE_MASK; + val |= UART_EXTINP_CTS_NOSENSE_MASK; + bcm_uart_writel(port, val, UART_EXTINP_REG); + + /* register irq and enable rx interrupts */ + ret = request_irq(port->irq, bcm_uart_interrupt, 0, + dev_name(port->dev), port); + if (ret) + return ret; + bcm_uart_writel(port, UART_RX_INT_MASK, UART_IR_REG); + bcm_uart_enable(port); + return 0; +} + +/* + * serial core request to flush & disable uart + */ +static void bcm_uart_shutdown(struct uart_port *port) +{ + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + bcm_uart_writel(port, 0, UART_IR_REG); + spin_unlock_irqrestore(&port->lock, flags); + + bcm_uart_disable(port); + bcm_uart_flush(port); + free_irq(port->irq, port); +} + +/* + * serial core request to change current uart setting + */ +static void bcm_uart_set_termios(struct uart_port *port, struct ktermios *new, + const struct ktermios *old) +{ + unsigned int ctl, baud, quot, ier; + unsigned long flags; + int tries; + + spin_lock_irqsave(&port->lock, flags); + + /* Drain the hot tub fully before we power it off for the winter. */ + for (tries = 3; !bcm_uart_tx_empty(port) && tries; tries--) + mdelay(10); + + /* disable uart while changing speed */ + bcm_uart_disable(port); + bcm_uart_flush(port); + + /* update Control register */ + ctl = bcm_uart_readl(port, UART_CTL_REG); + ctl &= ~UART_CTL_BITSPERSYM_MASK; + + switch (new->c_cflag & CSIZE) { + case CS5: + ctl |= (0 << UART_CTL_BITSPERSYM_SHIFT); + break; + case CS6: + ctl |= (1 << UART_CTL_BITSPERSYM_SHIFT); + break; + case CS7: + ctl |= (2 << UART_CTL_BITSPERSYM_SHIFT); + break; + default: + ctl |= (3 << UART_CTL_BITSPERSYM_SHIFT); + break; + } + + ctl &= ~UART_CTL_STOPBITS_MASK; + if (new->c_cflag & CSTOPB) + ctl |= UART_CTL_STOPBITS_2; + else + ctl |= UART_CTL_STOPBITS_1; + + ctl &= ~(UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK); + if (new->c_cflag & PARENB) + ctl |= (UART_CTL_RXPAREN_MASK | UART_CTL_TXPAREN_MASK); + ctl &= ~(UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK); + if (new->c_cflag & PARODD) + ctl |= (UART_CTL_RXPAREVEN_MASK | UART_CTL_TXPAREVEN_MASK); + bcm_uart_writel(port, ctl, UART_CTL_REG); + + /* update Baudword register */ + baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16); + quot = uart_get_divisor(port, baud) - 1; + bcm_uart_writel(port, quot, UART_BAUD_REG); + + /* update Interrupt register */ + ier = bcm_uart_readl(port, UART_IR_REG); + + ier &= ~UART_IR_MASK(UART_IR_EXTIP); + if (UART_ENABLE_MS(port, new->c_cflag)) + ier |= UART_IR_MASK(UART_IR_EXTIP); + + bcm_uart_writel(port, ier, UART_IR_REG); + + /* update read/ignore mask */ + port->read_status_mask = UART_FIFO_VALID_MASK; + if (new->c_iflag & INPCK) { + port->read_status_mask |= UART_FIFO_FRAMEERR_MASK; + port->read_status_mask |= UART_FIFO_PARERR_MASK; + } + if (new->c_iflag & (IGNBRK | BRKINT)) + port->read_status_mask |= UART_FIFO_BRKDET_MASK; + + port->ignore_status_mask = 0; + if (new->c_iflag & IGNPAR) + port->ignore_status_mask |= UART_FIFO_PARERR_MASK; + if (new->c_iflag & IGNBRK) + port->ignore_status_mask |= UART_FIFO_BRKDET_MASK; + if (!(new->c_cflag & CREAD)) + port->ignore_status_mask |= UART_FIFO_VALID_MASK; + + uart_update_timeout(port, new->c_cflag, baud); + bcm_uart_enable(port); + spin_unlock_irqrestore(&port->lock, flags); +} + +/* + * serial core request to claim uart iomem + */ +static int bcm_uart_request_port(struct uart_port *port) +{ + /* UARTs always present */ + return 0; +} + +/* + * serial core request to release uart iomem + */ +static void bcm_uart_release_port(struct uart_port *port) +{ + /* Nothing to release ... */ +} + +/* + * serial core request to do any port required autoconfiguration + */ +static void bcm_uart_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) { + if (bcm_uart_request_port(port)) + return; + port->type = PORT_BCM63XX; + } +} + +/* + * serial core request to check that port information in serinfo are + * suitable + */ +static int bcm_uart_verify_port(struct uart_port *port, + struct serial_struct *serinfo) +{ + if (port->type != PORT_BCM63XX) + return -EINVAL; + if (port->irq != serinfo->irq) + return -EINVAL; + if (port->iotype != serinfo->io_type) + return -EINVAL; + if (port->mapbase != (unsigned long)serinfo->iomem_base) + return -EINVAL; + return 0; +} + +/* serial core callbacks */ +static const struct uart_ops bcm_uart_ops = { + .tx_empty = bcm_uart_tx_empty, + .get_mctrl = bcm_uart_get_mctrl, + .set_mctrl = bcm_uart_set_mctrl, + .start_tx = bcm_uart_start_tx, + .stop_tx = bcm_uart_stop_tx, + .stop_rx = bcm_uart_stop_rx, + .enable_ms = bcm_uart_enable_ms, + .break_ctl = bcm_uart_break_ctl, + .startup = bcm_uart_startup, + .shutdown = bcm_uart_shutdown, + .set_termios = bcm_uart_set_termios, + .type = bcm_uart_type, + .release_port = bcm_uart_release_port, + .request_port = bcm_uart_request_port, + .config_port = bcm_uart_config_port, + .verify_port = bcm_uart_verify_port, +}; + + + +#ifdef CONFIG_SERIAL_BCM63XX_CONSOLE +static void wait_for_xmitr(struct uart_port *port) +{ + unsigned int tmout; + + /* Wait up to 10ms for the character(s) to be sent. */ + tmout = 10000; + while (--tmout) { + unsigned int val; + + val = bcm_uart_readl(port, UART_IR_REG); + if (val & UART_IR_STAT(UART_IR_TXEMPTY)) + break; + udelay(1); + } + + /* Wait up to 1s for flow control if necessary */ + if (port->flags & UPF_CONS_FLOW) { + tmout = 1000000; + while (--tmout) { + unsigned int val; + + val = bcm_uart_readl(port, UART_EXTINP_REG); + if (val & UART_EXTINP_CTS_MASK) + break; + udelay(1); + } + } +} + +/* + * output given char + */ +static void bcm_console_putchar(struct uart_port *port, unsigned char ch) +{ + wait_for_xmitr(port); + bcm_uart_writel(port, ch, UART_FIFO_REG); +} + +/* + * console core request to output given string + */ +static void bcm_console_write(struct console *co, const char *s, + unsigned int count) +{ + struct uart_port *port; + unsigned long flags; + int locked; + + port = &ports[co->index]; + + local_irq_save(flags); + if (port->sysrq) { + /* bcm_uart_interrupt() already took the lock */ + locked = 0; + } else if (oops_in_progress) { + locked = spin_trylock(&port->lock); + } else { + spin_lock(&port->lock); + locked = 1; + } + + /* call helper to deal with \r\n */ + uart_console_write(port, s, count, bcm_console_putchar); + + /* and wait for char to be transmitted */ + wait_for_xmitr(port); + + if (locked) + spin_unlock(&port->lock); + local_irq_restore(flags); +} + +/* + * console core request to setup given console, find matching uart + * port and setup it. + */ +static int bcm_console_setup(struct console *co, char *options) +{ + struct uart_port *port; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (co->index < 0 || co->index >= BCM63XX_NR_UARTS) + return -EINVAL; + port = &ports[co->index]; + if (!port->membase) + return -ENODEV; + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct uart_driver bcm_uart_driver; + +static struct console bcm63xx_console = { + .name = "ttyS", + .write = bcm_console_write, + .device = uart_console_device, + .setup = bcm_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &bcm_uart_driver, +}; + +static int __init bcm63xx_console_init(void) +{ + register_console(&bcm63xx_console); + return 0; +} + +console_initcall(bcm63xx_console_init); + +static void bcm_early_write(struct console *con, const char *s, unsigned n) +{ + struct earlycon_device *dev = con->data; + + uart_console_write(&dev->port, s, n, bcm_console_putchar); + wait_for_xmitr(&dev->port); +} + +static int __init bcm_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = bcm_early_write; + return 0; +} + +OF_EARLYCON_DECLARE(bcm63xx_uart, "brcm,bcm6345-uart", bcm_early_console_setup); + +#define BCM63XX_CONSOLE (&bcm63xx_console) +#else +#define BCM63XX_CONSOLE NULL +#endif /* CONFIG_SERIAL_BCM63XX_CONSOLE */ + +static struct uart_driver bcm_uart_driver = { + .owner = THIS_MODULE, + .driver_name = "bcm63xx_uart", + .dev_name = "ttyS", + .major = TTY_MAJOR, + .minor = 64, + .nr = BCM63XX_NR_UARTS, + .cons = BCM63XX_CONSOLE, +}; + +/* + * platform driver probe/remove callback + */ +static int bcm_uart_probe(struct platform_device *pdev) +{ + struct resource *res_mem; + struct uart_port *port; + struct clk *clk; + int ret; + + if (pdev->dev.of_node) { + pdev->id = of_alias_get_id(pdev->dev.of_node, "serial"); + + if (pdev->id < 0) + pdev->id = of_alias_get_id(pdev->dev.of_node, "uart"); + } + + if (pdev->id < 0 || pdev->id >= BCM63XX_NR_UARTS) + return -EINVAL; + + port = &ports[pdev->id]; + if (port->membase) + return -EBUSY; + memset(port, 0, sizeof(*port)); + + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res_mem) + return -ENODEV; + + port->mapbase = res_mem->start; + port->membase = devm_ioremap_resource(&pdev->dev, res_mem); + if (IS_ERR(port->membase)) + return PTR_ERR(port->membase); + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + return ret; + port->irq = ret; + + clk = clk_get(&pdev->dev, "refclk"); + if (IS_ERR(clk) && pdev->dev.of_node) + clk = of_clk_get(pdev->dev.of_node, 0); + + if (IS_ERR(clk)) + return -ENODEV; + + port->iotype = UPIO_MEM; + port->ops = &bcm_uart_ops; + port->flags = UPF_BOOT_AUTOCONF; + port->dev = &pdev->dev; + port->fifosize = 16; + port->uartclk = clk_get_rate(clk) / 2; + port->line = pdev->id; + port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_BCM63XX_CONSOLE); + clk_put(clk); + + ret = uart_add_one_port(&bcm_uart_driver, port); + if (ret) { + ports[pdev->id].membase = NULL; + return ret; + } + platform_set_drvdata(pdev, port); + return 0; +} + +static int bcm_uart_remove(struct platform_device *pdev) +{ + struct uart_port *port; + + port = platform_get_drvdata(pdev); + uart_remove_one_port(&bcm_uart_driver, port); + /* mark port as free */ + ports[pdev->id].membase = NULL; + return 0; +} + +static const struct of_device_id bcm63xx_of_match[] = { + { .compatible = "brcm,bcm6345-uart" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, bcm63xx_of_match); + +/* + * platform driver stuff + */ +static struct platform_driver bcm_uart_platform_driver = { + .probe = bcm_uart_probe, + .remove = bcm_uart_remove, + .driver = { + .name = "bcm63xx_uart", + .of_match_table = bcm63xx_of_match, + }, +}; + +static int __init bcm_uart_init(void) +{ + int ret; + + ret = uart_register_driver(&bcm_uart_driver); + if (ret) + return ret; + + ret = platform_driver_register(&bcm_uart_platform_driver); + if (ret) + uart_unregister_driver(&bcm_uart_driver); + + return ret; +} + +static void __exit bcm_uart_exit(void) +{ + platform_driver_unregister(&bcm_uart_platform_driver); + uart_unregister_driver(&bcm_uart_driver); +} + +module_init(bcm_uart_init); +module_exit(bcm_uart_exit); + +MODULE_AUTHOR("Maxime Bizon <mbizon@freebox.fr>"); +MODULE_DESCRIPTION("Broadcom 63xx integrated uart driver"); +MODULE_LICENSE("GPL"); |