diff options
| -rw-r--r-- | drivers/serial/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/serial/Makefile | 1 | ||||
| -rw-r--r-- | drivers/serial/timbuart.c | 520 | ||||
| -rw-r--r-- | drivers/serial/timbuart.h | 58 | ||||
| -rw-r--r-- | include/linux/serial_core.h | 3 |
5 files changed, 589 insertions, 0 deletions
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 343e3a35b6a3..3391ef0d761d 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -1433,4 +1433,11 @@ config SPORT_BAUD_RATE default 19200 if (SERIAL_SPORT_BAUD_RATE_19200) default 9600 if (SERIAL_SPORT_BAUD_RATE_9600) +config SERIAL_TIMBERDALE + tristate "Support for timberdale UART" + depends on MFD_TIMBERDALE + select SERIAL_CORE + ---help--- + Add support for UART controller on timberdale. + endmenu diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index d438eb2a73de..45a8658f54d5 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -77,3 +77,4 @@ obj-$(CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL) += nwpserial.o obj-$(CONFIG_SERIAL_KS8695) += serial_ks8695.o obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o obj-$(CONFIG_SERIAL_QE) += ucc_uart.o +obj-$(CONFIG_SERIAL_TIMBERDALE) += timbuart.o diff --git a/drivers/serial/timbuart.c b/drivers/serial/timbuart.c new file mode 100644 index 000000000000..30ba3c4cc180 --- /dev/null +++ b/drivers/serial/timbuart.c @@ -0,0 +1,520 @@ +/* + * timbuart.c timberdale FPGA UART driver + * Copyright (c) 2009 Intel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* Supports: + * Timberdale FPGA UART + */ + +#include <linux/pci.h> +#include <linux/interrupt.h> +#include <linux/serial_core.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/ioport.h> + +#include "timbuart.h" + +struct timbuart_port { + struct uart_port port; + struct tasklet_struct tasklet; + int usedma; + u8 last_ier; + struct platform_device *dev; +}; + +static int baudrates[] = {9600, 19200, 38400, 57600, 115200, 230400, 460800, + 921600, 1843200, 3250000}; + +static void timbuart_mctrl_check(struct uart_port *port, u8 isr, u8 *ier); + +static irqreturn_t timbuart_handleinterrupt(int irq, void *devid); + +static void timbuart_stop_rx(struct uart_port *port) +{ + /* spin lock held by upper layer, disable all RX interrupts */ + u8 ier = ioread8(port->membase + TIMBUART_IER) & ~RXFLAGS; + iowrite8(ier, port->membase + TIMBUART_IER); +} + +static void timbuart_stop_tx(struct uart_port *port) +{ + /* spinlock held by upper layer, disable TX interrupt */ + u8 ier = ioread8(port->membase + TIMBUART_IER) & ~TXBAE; + iowrite8(ier, port->membase + TIMBUART_IER); +} + +static void timbuart_start_tx(struct uart_port *port) +{ + struct timbuart_port *uart = + container_of(port, struct timbuart_port, port); + + /* do not transfer anything here -> fire off the tasklet */ + tasklet_schedule(&uart->tasklet); +} + +static void timbuart_flush_buffer(struct uart_port *port) +{ + u8 ctl = ioread8(port->membase + TIMBUART_CTRL) | TIMBUART_CTRL_FLSHTX; + + iowrite8(ctl, port->membase + TIMBUART_CTRL); + iowrite8(TXBF, port->membase + TIMBUART_ISR); +} + +static void timbuart_rx_chars(struct uart_port *port) +{ + struct tty_struct *tty = port->info->port.tty; + + while (ioread8(port->membase + TIMBUART_ISR) & RXDP) { + u8 ch = ioread8(port->membase + TIMBUART_RXFIFO); + port->icount.rx++; + tty_insert_flip_char(tty, ch, TTY_NORMAL); + } + + spin_unlock(&port->lock); + tty_flip_buffer_push(port->info->port.tty); + spin_lock(&port->lock); + + dev_dbg(port->dev, "%s - total read %d bytes\n", + __func__, port->icount.rx); +} + +static void timbuart_tx_chars(struct uart_port *port) +{ + struct circ_buf *xmit = &port->info->xmit; + + while (!(ioread8(port->membase + TIMBUART_ISR) & TXBF) && + !uart_circ_empty(xmit)) { + iowrite8(xmit->buf[xmit->tail], + port->membase + TIMBUART_TXFIFO); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + port->icount.tx++; + } + + dev_dbg(port->dev, + "%s - total written %d bytes, CTL: %x, RTS: %x, baud: %x\n", + __func__, + port->icount.tx, + ioread8(port->membase + TIMBUART_CTRL), + port->mctrl & TIOCM_RTS, + ioread8(port->membase + TIMBUART_BAUDRATE)); +} + +static void timbuart_handle_tx_port(struct uart_port *port, u8 isr, u8 *ier) +{ + struct timbuart_port *uart = + container_of(port, struct timbuart_port, port); + struct circ_buf *xmit = &port->info->xmit; + + if (uart_circ_empty(xmit) || uart_tx_stopped(port)) + return; + + if (port->x_char) + return; + + if (isr & TXFLAGS) { + timbuart_tx_chars(port); + /* clear all TX interrupts */ + iowrite8(TXFLAGS, port->membase + TIMBUART_ISR); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + } else + /* Re-enable any tx interrupt */ + *ier |= uart->last_ier & TXFLAGS; + + /* enable interrupts if there are chars in the transmit buffer, + * Or if we delivered some bytes and want the almost empty interrupt + * we wake up the upper layer later when we got the interrupt + * to give it some time to go out... + */ + if (!uart_circ_empty(xmit)) + *ier |= TXBAE; + + dev_dbg(port->dev, "%s - leaving\n", __func__); +} + +void timbuart_handle_rx_port(struct uart_port *port, u8 isr, u8 *ier) +{ + if (isr & RXFLAGS) { + /* Some RX status is set */ + if (isr & RXBF) { + u8 ctl = ioread8(port->membase + TIMBUART_CTRL) | + TIMBUART_CTRL_FLSHRX; + iowrite8(ctl, port->membase + TIMBUART_CTRL); + port->icount.overrun++; + } else if (isr & (RXDP)) + timbuart_rx_chars(port); + + /* ack all RX interrupts */ + iowrite8(RXFLAGS, port->membase + TIMBUART_ISR); + } + + /* always have the RX interrupts enabled */ + *ier |= RXBAF | RXBF | RXTT; + + dev_dbg(port->dev, "%s - leaving\n", __func__); +} + +void timbuart_tasklet(unsigned long arg) +{ + struct timbuart_port *uart = (struct timbuart_port *)arg; + u8 isr, ier = 0; + + spin_lock(&uart->port.lock); + + isr = ioread8(uart->port.membase + TIMBUART_ISR); + dev_dbg(uart->port.dev, "%s ISR: %x\n", __func__, isr); + + if (!uart->usedma) + timbuart_handle_tx_port(&uart->port, isr, &ier); + + timbuart_mctrl_check(&uart->port, isr, &ier); + + if (!uart->usedma) + timbuart_handle_rx_port(&uart->port, isr, &ier); + + iowrite8(ier, uart->port.membase + TIMBUART_IER); + + spin_unlock(&uart->port.lock); + dev_dbg(uart->port.dev, "%s leaving\n", __func__); +} + +static unsigned int timbuart_tx_empty(struct uart_port *port) +{ + u8 isr = ioread8(port->membase + TIMBUART_ISR); + + return (isr & TXBAE) ? TIOCSER_TEMT : 0; +} + +static unsigned int timbuart_get_mctrl(struct uart_port *port) +{ + u8 cts = ioread8(port->membase + TIMBUART_CTRL); + dev_dbg(port->dev, "%s - cts %x\n", __func__, cts); + + if (cts & TIMBUART_CTRL_CTS) + return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; + else + return TIOCM_DSR | TIOCM_CAR; +} + +static void timbuart_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + dev_dbg(port->dev, "%s - %x\n", __func__, mctrl); + + if (mctrl & TIOCM_RTS) + iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL); + else + iowrite8(TIMBUART_CTRL_RTS, port->membase + TIMBUART_CTRL); +} + +static void timbuart_mctrl_check(struct uart_port *port, u8 isr, u8 *ier) +{ + unsigned int cts; + + if (isr & CTS_DELTA) { + /* ack */ + iowrite8(CTS_DELTA, port->membase + TIMBUART_ISR); + cts = timbuart_get_mctrl(port); + uart_handle_cts_change(port, cts & TIOCM_CTS); + wake_up_interruptible(&port->info->delta_msr_wait); + } + + *ier |= CTS_DELTA; +} + +static void timbuart_enable_ms(struct uart_port *port) +{ + /* N/A */ +} + +static void timbuart_break_ctl(struct uart_port *port, int ctl) +{ + /* N/A */ +} + +static int timbuart_startup(struct uart_port *port) +{ + struct timbuart_port *uart = + container_of(port, struct timbuart_port, port); + + dev_dbg(port->dev, "%s\n", __func__); + + iowrite8(TIMBUART_CTRL_FLSHRX, port->membase + TIMBUART_CTRL); + iowrite8(0xff, port->membase + TIMBUART_ISR); + /* Enable all but TX interrupts */ + iowrite8(RXBAF | RXBF | RXTT | CTS_DELTA, + port->membase + TIMBUART_IER); + + return request_irq(port->irq, timbuart_handleinterrupt, IRQF_SHARED, + "timb-uart", uart); +} + +static void timbuart_shutdown(struct uart_port *port) +{ + struct timbuart_port *uart = + container_of(port, struct timbuart_port, port); + dev_dbg(port->dev, "%s\n", __func__); + free_irq(port->irq, uart); + iowrite8(0, port->membase + TIMBUART_IER); +} + +static int get_bindex(int baud) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(baudrates); i++) + if (baud == baudrates[i]) + return i; + + return -1; +} + +static void timbuart_set_termios(struct uart_port *port, + struct ktermios *termios, + struct ktermios *old) +{ + unsigned int baud; + short bindex; + unsigned long flags; + + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); + bindex = get_bindex(baud); + dev_dbg(port->dev, "%s - bindex %d\n", __func__, bindex); + + if (bindex < 0) { + printk(KERN_ALERT "timbuart: Unsupported baud rate\n"); + } else { + spin_lock_irqsave(&port->lock, flags); + iowrite8((u8)bindex, port->membase + TIMBUART_BAUDRATE); + uart_update_timeout(port, termios->c_cflag, baud); + spin_unlock_irqrestore(&port->lock, flags); + } +} + +static const char *timbuart_type(struct uart_port *port) +{ + return port->type == PORT_UNKNOWN ? "timbuart" : NULL; +} + +/* We do not request/release mappings of the registers here, + * currently it's done in the proble function. + */ +static void timbuart_release_port(struct uart_port *port) +{ + struct platform_device *pdev = to_platform_device(port->dev); + int size = + resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0)); + + if (port->flags & UPF_IOREMAP) { + iounmap(port->membase); + port->membase = NULL; + } + + release_mem_region(port->mapbase, size); +} + +static int timbuart_request_port(struct uart_port *port) +{ + struct platform_device *pdev = to_platform_device(port->dev); + int size = + resource_size(platform_get_resource(pdev, IORESOURCE_MEM, 0)); + + if (!request_mem_region(port->mapbase, size, "timb-uart")) + return -EBUSY; + + if (port->flags & UPF_IOREMAP) { + port->membase = ioremap(port->mapbase, size); + if (port->membase == NULL) { + release_mem_region(port->mapbase, size); + return -ENOMEM; + } + } + + return 0; +} + +static irqreturn_t timbuart_handleinterrupt(int irq, void *devid) +{ + struct timbuart_port *uart = (struct timbuart_port *)devid; + + if (ioread8(uart->port.membase + TIMBUART_IPR)) { + uart->last_ier = ioread8(uart->port.membase + TIMBUART_IER); + + /* disable interrupts, the tasklet enables them again */ + iowrite8(0, uart->port.membase + TIMBUART_IER); + + /* fire off bottom half */ + tasklet_schedule(&uart->tasklet); + + return IRQ_HANDLED; + } else + return IRQ_NONE; +} + +/* + * Configure/autoconfigure the port. + */ +static void timbuart_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE) { + port->type = PORT_TIMBUART; + timbuart_request_port(port); + } +} + +static int timbuart_verify_port(struct uart_port *port, + struct serial_struct *ser) +{ + /* we don't want the core code to modify any port params */ + return -EINVAL; +} + +static struct uart_ops timbuart_ops = { + .tx_empty = timbuart_tx_empty, + .set_mctrl = timbuart_set_mctrl, + .get_mctrl = timbuart_get_mctrl, + .stop_tx = timbuart_stop_tx, + .start_tx = timbuart_start_tx, + .flush_buffer = timbuart_flush_buffer, + .stop_rx = timbuart_stop_rx, + .enable_ms = timbuart_enable_ms, + .break_ctl = timbuart_break_ctl, + .startup = timbuart_startup, + .shutdown = timbuart_shutdown, + .set_termios = timbuart_set_termios, + .type = timbuart_type, + .release_port = timbuart_release_port, + .request_port = timbuart_request_port, + .config_port = timbuart_config_port, + .verify_port = timbuart_verify_port +}; + +static struct uart_driver timbuart_driver = { + .owner = THIS_MODULE, + .driver_name = "timberdale_uart", + .dev_name = "ttyTU", + .major = TIMBUART_MAJOR, + .minor = TIMBUART_MINOR, + .nr = 1 +}; + +static int timbuart_probe(struct platform_device *dev) +{ + int err; + struct timbuart_port *uart; + struct resource *iomem; + + dev_dbg(&dev->dev, "%s\n", __func__); + + uart = kzalloc(sizeof(*uart), GFP_KERNEL); + if (!uart) { + err = -EINVAL; + goto err_mem; + } + + uart->usedma = 0; + + uart->port.uartclk = 3250000 * 16; + uart->port.fifosize = TIMBUART_FIFO_SIZE; + uart->port.regshift = 2; + uart->port.iotype = UPIO_MEM; + uart->port.ops = &timbuart_ops; + uart->port.irq = 0; + uart->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP; + uart->port.line = 0; + uart->port.dev = &dev->dev; + + iomem = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (!iomem) { + err = -ENOMEM; + goto err_register; + } + uart->port.mapbase = iomem->start; + uart->port.membase = NULL; + + uart->port.irq = platform_get_irq(dev, 0); + if (uart->port.irq < 0) { + err = -EINVAL; + goto err_register; + } + + tasklet_init(&uart->tasklet, timbuart_tasklet, (unsigned long)uart); + + err = uart_register_driver(&timbuart_driver); + if (err) + goto err_register; + + err = uart_add_one_port(&timbuart_driver, &uart->port); + if (err) + goto err_add_port; + + platform_set_drvdata(dev, uart); + + return 0; + +err_add_port: + uart_unregister_driver(&timbuart_driver); +err_register: + kfree(uart); +err_mem: + printk(KERN_ERR "timberdale: Failed to register Timberdale UART: %d\n", + err); + + return err; +} + +static int timbuart_remove(struct platform_device *dev) +{ + struct timbuart_port *uart = platform_get_drvdata(dev); + + tasklet_kill(&uart->tasklet); + uart_remove_one_port(&timbuart_driver, &uart->port); + uart_unregister_driver(&timbuart_driver); + kfree(uart); + + return 0; +} + +static struct platform_driver timbuart_platform_driver = { + .driver = { + .name = "timb-uart", + .owner = THIS_MODULE, + }, + .probe = timbuart_probe, + .remove = timbuart_remove, +}; + +/*--------------------------------------------------------------------------*/ + +static int __init timbuart_init(void) +{ + return platform_driver_register(&timbuart_platform_driver); +} + +static void __exit timbuart_exit(void) +{ + platform_driver_unregister(&timbuart_platform_driver); +} + +module_init(timbuart_init); +module_exit(timbuart_exit); + +MODULE_DESCRIPTION("Timberdale UART driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:timb-uart"); + diff --git a/drivers/serial/timbuart.h b/drivers/serial/timbuart.h new file mode 100644 index 000000000000..7e566766bc43 --- /dev/null +++ b/drivers/serial/timbuart.h @@ -0,0 +1,58 @@ +/* + * timbuart.c timberdale FPGA GPIO driver + * Copyright (c) 2009 Intel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* Supports: + * Timberdale FPGA UART + */ + +#ifndef _TIMBUART_H +#define _TIMBUART_H + +#define TIMBUART_FIFO_SIZE 2048 + +#define TIMBUART_RXFIFO 0x08 +#define TIMBUART_TXFIFO 0x0c +#define TIMBUART_IER 0x10 +#define TIMBUART_IPR 0x14 +#define TIMBUART_ISR 0x18 +#define TIMBUART_CTRL 0x1c +#define TIMBUART_BAUDRATE 0x20 + +#define TIMBUART_CTRL_RTS 0x01 +#define TIMBUART_CTRL_CTS 0x02 +#define TIMBUART_CTRL_FLSHTX 0x40 +#define TIMBUART_CTRL_FLSHRX 0x80 + +#define TXBF 0x01 +#define TXBAE 0x02 +#define CTS_DELTA 0x04 +#define RXDP 0x08 +#define RXBAF 0x10 +#define RXBF 0x20 +#define RXTT 0x40 +#define RXBNAE 0x80 +#define TXBE 0x100 + +#define RXFLAGS (RXDP | RXBAF | RXBF | RXTT | RXBNAE) +#define TXFLAGS (TXBF | TXBAE) + +#define TIMBUART_MAJOR 204 +#define TIMBUART_MINOR 192 + +#endif /* _TIMBUART_H */ + diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 48766ea845cf..6fd80c4243f1 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -168,6 +168,9 @@ /* MAX3100 */ #define PORT_MAX3100 86 +/* Timberdale UART */ +#define PORT_TIMBUART 87 + #ifdef __KERNEL__ #include <linux/compiler.h> |