From eea63e0e8a60d00485b47fb6e75d9aa2566b989b Mon Sep 17 00:00:00 2001 From: Thomas Bogendoerfer Date: Wed, 6 Feb 2008 01:37:27 -0800 Subject: SC26XX: New serial driver for SC2681 uarts New serial driver for SC2681/SC2691 uarts. Older SNI RM400 machines are using these chips for onboard serial ports. Signed-off-by: Thomas Bogendoerfer Cc: Ralf Baechle Cc: Alan Cox Cc: Torben Mathiasen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/serial/sc26xx.c | 755 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 755 insertions(+) create mode 100644 drivers/serial/sc26xx.c (limited to 'drivers/serial/sc26xx.c') diff --git a/drivers/serial/sc26xx.c b/drivers/serial/sc26xx.c new file mode 100644 index 00000000000..a350b6d2a18 --- /dev/null +++ b/drivers/serial/sc26xx.c @@ -0,0 +1,755 @@ +/* + * SC268xx.c: Serial driver for Philiphs SC2681/SC2692 devices. + * + * Copyright (C) 2006,2007 Thomas Bogendörfer (tsbogend@alpha.franken.de) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#if defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + +#include + +#define SC26XX_MAJOR 204 +#define SC26XX_MINOR_START 205 +#define SC26XX_NR 2 + +struct uart_sc26xx_port { + struct uart_port port[2]; + u8 dsr_mask[2]; + u8 cts_mask[2]; + u8 dcd_mask[2]; + u8 ri_mask[2]; + u8 dtr_mask[2]; + u8 rts_mask[2]; + u8 imr; +}; + +/* register common to both ports */ +#define RD_ISR 0x14 +#define RD_IPR 0x34 + +#define WR_ACR 0x10 +#define WR_IMR 0x14 +#define WR_OPCR 0x34 +#define WR_OPR_SET 0x38 +#define WR_OPR_CLR 0x3C + +/* access common register */ +#define READ_SC(p, r) readb((p)->membase + RD_##r) +#define WRITE_SC(p, r, v) writeb((v), (p)->membase + WR_##r) + +/* register per port */ +#define RD_PORT_MRx 0x00 +#define RD_PORT_SR 0x04 +#define RD_PORT_RHR 0x0c + +#define WR_PORT_MRx 0x00 +#define WR_PORT_CSR 0x04 +#define WR_PORT_CR 0x08 +#define WR_PORT_THR 0x0c + +/* SR bits */ +#define SR_BREAK (1 << 7) +#define SR_FRAME (1 << 6) +#define SR_PARITY (1 << 5) +#define SR_OVERRUN (1 << 4) +#define SR_TXRDY (1 << 2) +#define SR_RXRDY (1 << 0) + +#define CR_RES_MR (1 << 4) +#define CR_RES_RX (2 << 4) +#define CR_RES_TX (3 << 4) +#define CR_STRT_BRK (6 << 4) +#define CR_STOP_BRK (7 << 4) +#define CR_DIS_TX (1 << 3) +#define CR_ENA_TX (1 << 2) +#define CR_DIS_RX (1 << 1) +#define CR_ENA_RX (1 << 0) + +/* ISR bits */ +#define ISR_RXRDYB (1 << 5) +#define ISR_TXRDYB (1 << 4) +#define ISR_RXRDYA (1 << 1) +#define ISR_TXRDYA (1 << 0) + +/* IMR bits */ +#define IMR_RXRDY (1 << 1) +#define IMR_TXRDY (1 << 0) + +/* access port register */ +static inline u8 read_sc_port(struct uart_port *p, u8 reg) +{ + return readb(p->membase + p->line * 0x20 + reg); +} + +static inline void write_sc_port(struct uart_port *p, u8 reg, u8 val) +{ + writeb(val, p->membase + p->line * 0x20 + reg); +} + +#define READ_SC_PORT(p, r) read_sc_port(p, RD_PORT_##r) +#define WRITE_SC_PORT(p, r, v) write_sc_port(p, WR_PORT_##r, v) + +static void sc26xx_enable_irq(struct uart_port *port, int mask) +{ + struct uart_sc26xx_port *up; + int line = port->line; + + port -= line; + up = container_of(port, struct uart_sc26xx_port, port[0]); + + up->imr |= mask << (line * 4); + WRITE_SC(port, IMR, up->imr); +} + +static void sc26xx_disable_irq(struct uart_port *port, int mask) +{ + struct uart_sc26xx_port *up; + int line = port->line; + + port -= line; + up = container_of(port, struct uart_sc26xx_port, port[0]); + + up->imr &= ~(mask << (line * 4)); + WRITE_SC(port, IMR, up->imr); +} + +static struct tty_struct *receive_chars(struct uart_port *port) +{ + struct tty_struct *tty = NULL; + int limit = 10000; + unsigned char ch; + char flag; + u8 status; + + if (port->info != NULL) /* Unopened serial console */ + tty = port->info->tty; + + while (limit-- > 0) { + status = READ_SC_PORT(port, SR); + if (!(status & SR_RXRDY)) + break; + ch = READ_SC_PORT(port, RHR); + + flag = TTY_NORMAL; + port->icount.rx++; + + if (unlikely(status & (SR_BREAK | SR_FRAME | + SR_PARITY | SR_OVERRUN))) { + if (status & SR_BREAK) { + status &= ~(SR_PARITY | SR_FRAME); + port->icount.brk++; + if (uart_handle_break(port)) + continue; + } else if (status & SR_PARITY) + port->icount.parity++; + else if (status & SR_FRAME) + port->icount.frame++; + if (status & SR_OVERRUN) + port->icount.overrun++; + + status &= port->read_status_mask; + if (status & SR_BREAK) + flag = TTY_BREAK; + else if (status & SR_PARITY) + flag = TTY_PARITY; + else if (status & SR_FRAME) + flag = TTY_FRAME; + } + + if (uart_handle_sysrq_char(port, ch)) + continue; + + if (status & port->ignore_status_mask) + continue; + + tty_insert_flip_char(tty, ch, flag); + } + return tty; +} + +static void transmit_chars(struct uart_port *port) +{ + struct circ_buf *xmit; + + if (!port->info) + return; + + xmit = &port->info->xmit; + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { + sc26xx_disable_irq(port, IMR_TXRDY); + return; + } + while (!uart_circ_empty(xmit)) { + if (!(READ_SC_PORT(port, SR) & SR_TXRDY)) + break; + + WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + } + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); +} + +static irqreturn_t sc26xx_interrupt(int irq, void *dev_id) +{ + struct uart_sc26xx_port *up = dev_id; + struct tty_struct *tty; + unsigned long flags; + u8 isr; + + spin_lock_irqsave(&up->port[0].lock, flags); + + tty = NULL; + isr = READ_SC(&up->port[0], ISR); + if (isr & ISR_TXRDYA) + transmit_chars(&up->port[0]); + if (isr & ISR_RXRDYA) + tty = receive_chars(&up->port[0]); + + spin_unlock(&up->port[0].lock); + + if (tty) + tty_flip_buffer_push(tty); + + spin_lock(&up->port[1].lock); + + tty = NULL; + if (isr & ISR_TXRDYB) + transmit_chars(&up->port[1]); + if (isr & ISR_RXRDYB) + tty = receive_chars(&up->port[1]); + + spin_unlock_irqrestore(&up->port[1].lock, flags); + + if (tty) + tty_flip_buffer_push(tty); + + return IRQ_HANDLED; +} + +/* port->lock is not held. */ +static unsigned int sc26xx_tx_empty(struct uart_port *port) +{ + return (READ_SC_PORT(port, SR) & SR_TXRDY) ? TIOCSER_TEMT : 0; +} + +/* port->lock held by caller. */ +static void sc26xx_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + struct uart_sc26xx_port *up; + int line = port->line; + + port -= line; + up = container_of(port, struct uart_sc26xx_port, port[0]); + + if (up->dtr_mask[line]) { + if (mctrl & TIOCM_DTR) + WRITE_SC(port, OPR_SET, up->dtr_mask[line]); + else + WRITE_SC(port, OPR_CLR, up->dtr_mask[line]); + } + if (up->rts_mask[line]) { + if (mctrl & TIOCM_RTS) + WRITE_SC(port, OPR_SET, up->rts_mask[line]); + else + WRITE_SC(port, OPR_CLR, up->rts_mask[line]); + } +} + +/* port->lock is held by caller and interrupts are disabled. */ +static unsigned int sc26xx_get_mctrl(struct uart_port *port) +{ + struct uart_sc26xx_port *up; + int line = port->line; + unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR; + u8 ipr; + + port -= line; + up = container_of(port, struct uart_sc26xx_port, port[0]); + ipr = READ_SC(port, IPR) ^ 0xff; + + if (up->dsr_mask[line]) { + mctrl &= ~TIOCM_DSR; + mctrl |= ipr & up->dsr_mask[line] ? TIOCM_DSR : 0; + } + if (up->cts_mask[line]) { + mctrl &= ~TIOCM_CTS; + mctrl |= ipr & up->cts_mask[line] ? TIOCM_CTS : 0; + } + if (up->dcd_mask[line]) { + mctrl &= ~TIOCM_CAR; + mctrl |= ipr & up->dcd_mask[line] ? TIOCM_CAR : 0; + } + if (up->ri_mask[line]) { + mctrl &= ~TIOCM_RNG; + mctrl |= ipr & up->ri_mask[line] ? TIOCM_RNG : 0; + } + return mctrl; +} + +/* port->lock held by caller. */ +static void sc26xx_stop_tx(struct uart_port *port) +{ + return; +} + +/* port->lock held by caller. */ +static void sc26xx_start_tx(struct uart_port *port) +{ + struct circ_buf *xmit = &port->info->xmit; + + while (!uart_circ_empty(xmit)) { + if (!(READ_SC_PORT(port, SR) & SR_TXRDY)) { + sc26xx_enable_irq(port, IMR_TXRDY); + break; + } + WRITE_SC_PORT(port, THR, xmit->buf[xmit->tail]); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + } +} + +/* port->lock held by caller. */ +static void sc26xx_stop_rx(struct uart_port *port) +{ +} + +/* port->lock held by caller. */ +static void sc26xx_enable_ms(struct uart_port *port) +{ +} + +/* port->lock is not held. */ +static void sc26xx_break_ctl(struct uart_port *port, int break_state) +{ + if (break_state == -1) + WRITE_SC_PORT(port, CR, CR_STRT_BRK); + else + WRITE_SC_PORT(port, CR, CR_STOP_BRK); +} + +/* port->lock is not held. */ +static int sc26xx_startup(struct uart_port *port) +{ + sc26xx_disable_irq(port, IMR_TXRDY | IMR_RXRDY); + WRITE_SC(port, OPCR, 0); + + /* reset tx and rx */ + WRITE_SC_PORT(port, CR, CR_RES_RX); + WRITE_SC_PORT(port, CR, CR_RES_TX); + + /* start rx/tx */ + WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX); + + /* enable irqs */ + sc26xx_enable_irq(port, IMR_RXRDY); + return 0; +} + +/* port->lock is not held. */ +static void sc26xx_shutdown(struct uart_port *port) +{ + /* disable interrupst */ + sc26xx_disable_irq(port, IMR_TXRDY | IMR_RXRDY); + + /* stop tx/rx */ + WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX); +} + +/* port->lock is not held. */ +static void sc26xx_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000); + unsigned int quot = uart_get_divisor(port, baud); + unsigned int iflag, cflag; + unsigned long flags; + u8 mr1, mr2, csr; + + spin_lock_irqsave(&port->lock, flags); + + while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc) + udelay(2); + + WRITE_SC_PORT(port, CR, CR_DIS_TX | CR_DIS_RX); + + iflag = termios->c_iflag; + cflag = termios->c_cflag; + + port->read_status_mask = SR_OVERRUN; + if (iflag & INPCK) + port->read_status_mask |= SR_PARITY | SR_FRAME; + if (iflag & (BRKINT | PARMRK)) + port->read_status_mask |= SR_BREAK; + + port->ignore_status_mask = 0; + if (iflag & IGNBRK) + port->ignore_status_mask |= SR_BREAK; + if ((cflag & CREAD) == 0) + port->ignore_status_mask |= SR_BREAK | SR_FRAME | + SR_PARITY | SR_OVERRUN; + + switch (cflag & CSIZE) { + case CS5: + mr1 = 0x00; + break; + case CS6: + mr1 = 0x01; + break; + case CS7: + mr1 = 0x02; + break; + default: + case CS8: + mr1 = 0x03; + break; + } + mr2 = 0x07; + if (cflag & CSTOPB) + mr2 = 0x0f; + if (cflag & PARENB) { + if (cflag & PARODD) + mr1 |= (1 << 2); + } else + mr1 |= (2 << 3); + + switch (baud) { + case 50: + csr = 0x00; + break; + case 110: + csr = 0x11; + break; + case 134: + csr = 0x22; + break; + case 200: + csr = 0x33; + break; + case 300: + csr = 0x44; + break; + case 600: + csr = 0x55; + break; + case 1200: + csr = 0x66; + break; + case 2400: + csr = 0x88; + break; + case 4800: + csr = 0x99; + break; + default: + case 9600: + csr = 0xbb; + break; + case 19200: + csr = 0xcc; + break; + } + + WRITE_SC_PORT(port, CR, CR_RES_MR); + WRITE_SC_PORT(port, MRx, mr1); + WRITE_SC_PORT(port, MRx, mr2); + + WRITE_SC(port, ACR, 0x80); + WRITE_SC_PORT(port, CSR, csr); + + /* reset tx and rx */ + WRITE_SC_PORT(port, CR, CR_RES_RX); + WRITE_SC_PORT(port, CR, CR_RES_TX); + + WRITE_SC_PORT(port, CR, CR_ENA_TX | CR_ENA_RX); + while ((READ_SC_PORT(port, SR) & ((1 << 3) | (1 << 2))) != 0xc) + udelay(2); + + /* XXX */ + uart_update_timeout(port, cflag, + (port->uartclk / (16 * quot))); + + spin_unlock_irqrestore(&port->lock, flags); +} + +static const char *sc26xx_type(struct uart_port *port) +{ + return "SC26XX"; +} + +static void sc26xx_release_port(struct uart_port *port) +{ +} + +static int sc26xx_request_port(struct uart_port *port) +{ + return 0; +} + +static void sc26xx_config_port(struct uart_port *port, int flags) +{ +} + +static int sc26xx_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + return -EINVAL; +} + +static struct uart_ops sc26xx_ops = { + .tx_empty = sc26xx_tx_empty, + .set_mctrl = sc26xx_set_mctrl, + .get_mctrl = sc26xx_get_mctrl, + .stop_tx = sc26xx_stop_tx, + .start_tx = sc26xx_start_tx, + .stop_rx = sc26xx_stop_rx, + .enable_ms = sc26xx_enable_ms, + .break_ctl = sc26xx_break_ctl, + .startup = sc26xx_startup, + .shutdown = sc26xx_shutdown, + .set_termios = sc26xx_set_termios, + .type = sc26xx_type, + .release_port = sc26xx_release_port, + .request_port = sc26xx_request_port, + .config_port = sc26xx_config_port, + .verify_port = sc26xx_verify_port, +}; + +static struct uart_port *sc26xx_port; + +#ifdef CONFIG_SERIAL_SC26XX_CONSOLE +static void sc26xx_console_putchar(struct uart_port *port, char c) +{ + unsigned long flags; + int limit = 1000000; + + spin_lock_irqsave(&port->lock, flags); + + while (limit-- > 0) { + if (READ_SC_PORT(port, SR) & SR_TXRDY) { + WRITE_SC_PORT(port, THR, c); + break; + } + udelay(2); + } + + spin_unlock_irqrestore(&port->lock, flags); +} + +static void sc26xx_console_write(struct console *con, const char *s, unsigned n) +{ + struct uart_port *port = sc26xx_port; + int i; + + for (i = 0; i < n; i++) { + if (*s == '\n') + sc26xx_console_putchar(port, '\r'); + sc26xx_console_putchar(port, *s++); + } +} + +static int __init sc26xx_console_setup(struct console *con, char *options) +{ + struct uart_port *port = sc26xx_port; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (port->type != PORT_SC26XX) + return -1; + + printk(KERN_INFO "Console: ttySC%d (SC26XX)\n", con->index); + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, con, baud, parity, bits, flow); +} + +static struct uart_driver sc26xx_reg; +static struct console sc26xx_console = { + .name = "ttySC", + .write = sc26xx_console_write, + .device = uart_console_device, + .setup = sc26xx_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &sc26xx_reg, +}; +#define SC26XX_CONSOLE &sc26xx_console +#else +#define SC26XX_CONSOLE NULL +#endif + +static struct uart_driver sc26xx_reg = { + .owner = THIS_MODULE, + .driver_name = "SC26xx", + .dev_name = "ttySC", + .major = SC26XX_MAJOR, + .minor = SC26XX_MINOR_START, + .nr = SC26XX_NR, + .cons = SC26XX_CONSOLE, +}; + +static u8 sc26xx_flags2mask(unsigned int flags, unsigned int bitpos) +{ + unsigned int bit = (flags >> bitpos) & 15; + + return bit ? (1 << (bit - 1)) : 0; +} + +static void __devinit sc26xx_init_masks(struct uart_sc26xx_port *up, + int line, unsigned int data) +{ + up->dtr_mask[line] = sc26xx_flags2mask(data, 0); + up->rts_mask[line] = sc26xx_flags2mask(data, 4); + up->dsr_mask[line] = sc26xx_flags2mask(data, 8); + up->cts_mask[line] = sc26xx_flags2mask(data, 12); + up->dcd_mask[line] = sc26xx_flags2mask(data, 16); + up->ri_mask[line] = sc26xx_flags2mask(data, 20); +} + +static int __devinit sc26xx_probe(struct platform_device *dev) +{ + struct resource *res; + struct uart_sc26xx_port *up; + unsigned int *sc26xx_data = dev->dev.platform_data; + int err; + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + up = kzalloc(sizeof *up, GFP_KERNEL); + if (unlikely(!up)) + return -ENOMEM; + + up->port[0].line = 0; + up->port[0].ops = &sc26xx_ops; + up->port[0].type = PORT_SC26XX; + up->port[0].uartclk = (29491200 / 16); /* arbitrary */ + + up->port[0].mapbase = res->start; + up->port[0].membase = ioremap_nocache(up->port[0].mapbase, 0x40); + up->port[0].iotype = UPIO_MEM; + up->port[0].irq = platform_get_irq(dev, 0); + + up->port[0].dev = &dev->dev; + + sc26xx_init_masks(up, 0, sc26xx_data[0]); + + sc26xx_port = &up->port[0]; + + up->port[1].line = 1; + up->port[1].ops = &sc26xx_ops; + up->port[1].type = PORT_SC26XX; + up->port[1].uartclk = (29491200 / 16); /* arbitrary */ + + up->port[1].mapbase = up->port[0].mapbase; + up->port[1].membase = up->port[0].membase; + up->port[1].iotype = UPIO_MEM; + up->port[1].irq = up->port[0].irq; + + up->port[1].dev = &dev->dev; + + sc26xx_init_masks(up, 1, sc26xx_data[1]); + + err = uart_register_driver(&sc26xx_reg); + if (err) + goto out_free_port; + + sc26xx_reg.tty_driver->name_base = sc26xx_reg.minor; + + err = uart_add_one_port(&sc26xx_reg, &up->port[0]); + if (err) + goto out_unregister_driver; + + err = uart_add_one_port(&sc26xx_reg, &up->port[1]); + if (err) + goto out_remove_port0; + + err = request_irq(up->port[0].irq, sc26xx_interrupt, 0, "sc26xx", up); + if (err) + goto out_remove_ports; + + dev_set_drvdata(&dev->dev, up); + return 0; + +out_remove_ports: + uart_remove_one_port(&sc26xx_reg, &up->port[1]); +out_remove_port0: + uart_remove_one_port(&sc26xx_reg, &up->port[0]); + +out_unregister_driver: + uart_unregister_driver(&sc26xx_reg); + +out_free_port: + kfree(up); + sc26xx_port = NULL; + return err; +} + + +static int __exit sc26xx_driver_remove(struct platform_device *dev) +{ + struct uart_sc26xx_port *up = dev_get_drvdata(&dev->dev); + + free_irq(up->port[0].irq, up); + + uart_remove_one_port(&sc26xx_reg, &up->port[0]); + uart_remove_one_port(&sc26xx_reg, &up->port[1]); + + uart_unregister_driver(&sc26xx_reg); + + kfree(up); + sc26xx_port = NULL; + + dev_set_drvdata(&dev->dev, NULL); + return 0; +} + +static struct platform_driver sc26xx_driver = { + .probe = sc26xx_probe, + .remove = __devexit_p(sc26xx_driver_remove), + .driver = { + .name = "SC26xx", + }, +}; + +static int __init sc26xx_init(void) +{ + return platform_driver_register(&sc26xx_driver); +} + +static void __exit sc26xx_exit(void) +{ + platform_driver_unregister(&sc26xx_driver); +} + +module_init(sc26xx_init); +module_exit(sc26xx_exit); + + +MODULE_AUTHOR("Thomas Bogendörfer"); +MODULE_DESCRIPTION("SC681/SC2692 serial driver"); +MODULE_VERSION("1.0"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3