diff options
Diffstat (limited to 'drivers/serial/atmel_serial.c')
-rw-r--r-- | drivers/serial/atmel_serial.c | 255 |
1 files changed, 150 insertions, 105 deletions
diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c index 60f5290..bb9c357 100644 --- a/drivers/serial/atmel_serial.c +++ b/drivers/serial/atmel_serial.c @@ -73,6 +73,7 @@ #define ATMEL_ISR_PASS_LIMIT 256 +/* UART registers. CR is write-only, hence no GET macro */ #define UART_PUT_CR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_CR) #define UART_GET_MR(port) __raw_readl((port)->membase + ATMEL_US_MR) #define UART_PUT_MR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_MR) @@ -86,8 +87,6 @@ #define UART_PUT_BRGR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_BRGR) #define UART_PUT_RTOR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_RTOR) -// #define UART_GET_CR(port) __raw_readl((port)->membase + ATMEL_US_CR) // is write-only - /* PDC registers */ #define UART_PUT_PTCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_PTCR) #define UART_GET_PTSR(port) __raw_readl((port)->membase + ATMEL_PDC_PTSR) @@ -100,8 +99,6 @@ #define UART_PUT_TPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TPR) #define UART_PUT_TCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TCR) -//#define UART_PUT_TNPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TNPR) -//#define UART_PUT_TNCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TNCR) static int (*atmel_open_hook)(struct uart_port *); static void (*atmel_close_hook)(struct uart_port *); @@ -141,8 +138,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) #ifdef CONFIG_ARCH_AT91RM9200 if (cpu_is_at91rm9200()) { /* - * AT91RM9200 Errata #39: RTS0 is not internally connected to PA21. - * We need to drive the pin manually. + * AT91RM9200 Errata #39: RTS0 is not internally connected + * to PA21. We need to drive the pin manually. */ if (port->mapbase == AT91RM9200_BASE_US0) { if (mctrl & TIOCM_RTS) @@ -227,7 +224,8 @@ static void atmel_stop_rx(struct uart_port *port) */ static void atmel_enable_ms(struct uart_port *port) { - UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC | ATMEL_US_CTSIC); + UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC + | ATMEL_US_DCDIC | ATMEL_US_CTSIC); } /* @@ -246,7 +244,7 @@ static void atmel_break_ctl(struct uart_port *port, int break_state) */ static void atmel_rx_chars(struct uart_port *port) { - struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port; + struct atmel_uart_port *atmel_port = (struct atmel_uart_port *)port; struct tty_struct *tty = port->info->tty; unsigned int status, ch, flg; @@ -265,10 +263,12 @@ static void atmel_rx_chars(struct uart_port *port) if (unlikely(status & (ATMEL_US_PARE | ATMEL_US_FRAME | ATMEL_US_OVRE | ATMEL_US_RXBRK) || atmel_port->break_active)) { - UART_PUT_CR(port, ATMEL_US_RSTSTA); /* clear error */ + /* clear error */ + UART_PUT_CR(port, ATMEL_US_RSTSTA); if (status & ATMEL_US_RXBRK && !atmel_port->break_active) { - status &= ~(ATMEL_US_PARE | ATMEL_US_FRAME); /* ignore side-effect */ + /* ignore side-effect */ + status &= ~(ATMEL_US_PARE | ATMEL_US_FRAME); port->icount.brk++; atmel_port->break_active = 1; UART_PUT_IER(port, ATMEL_US_RXBRK); @@ -308,7 +308,7 @@ static void atmel_rx_chars(struct uart_port *port) uart_insert_char(port, status, ATMEL_US_OVRE, ch, flg); - ignore_char: +ignore_char: status = UART_GET_CSR(port); } @@ -349,44 +349,73 @@ static void atmel_tx_chars(struct uart_port *port) } /* + * receive interrupt handler. + */ +static void +atmel_handle_receive(struct uart_port *port, unsigned int pending) +{ + struct atmel_uart_port *atmel_port = (struct atmel_uart_port *)port; + + /* Interrupt receive */ + if (pending & ATMEL_US_RXRDY) + atmel_rx_chars(port); + else if (pending & ATMEL_US_RXBRK) { + /* + * End of break detected. If it came along with a + * character, atmel_rx_chars will handle it. + */ + UART_PUT_CR(port, ATMEL_US_RSTSTA); + UART_PUT_IDR(port, ATMEL_US_RXBRK); + atmel_port->break_active = 0; + } +} + +/* + * transmit interrupt handler. + */ +static void +atmel_handle_transmit(struct uart_port *port, unsigned int pending) +{ + /* Interrupt transmit */ + if (pending & ATMEL_US_TXRDY) + atmel_tx_chars(port); +} + +/* + * status flags interrupt handler. + */ +static void +atmel_handle_status(struct uart_port *port, unsigned int pending, + unsigned int status) +{ + /* TODO: All reads to CSR will clear these interrupts! */ + if (pending & ATMEL_US_RIIC) + port->icount.rng++; + if (pending & ATMEL_US_DSRIC) + port->icount.dsr++; + if (pending & ATMEL_US_DCDIC) + uart_handle_dcd_change(port, !(status & ATMEL_US_DCD)); + if (pending & ATMEL_US_CTSIC) + uart_handle_cts_change(port, !(status & ATMEL_US_CTS)); + if (pending & (ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC + | ATMEL_US_CTSIC)) + wake_up_interruptible(&port->info->delta_msr_wait); +} + +/* * Interrupt handler */ static irqreturn_t atmel_interrupt(int irq, void *dev_id) { struct uart_port *port = dev_id; - struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port; unsigned int status, pending, pass_counter = 0; status = UART_GET_CSR(port); pending = status & UART_GET_IMR(port); while (pending) { - /* Interrupt receive */ - if (pending & ATMEL_US_RXRDY) - atmel_rx_chars(port); - else if (pending & ATMEL_US_RXBRK) { - /* - * End of break detected. If it came along - * with a character, atmel_rx_chars will - * handle it. - */ - UART_PUT_CR(port, ATMEL_US_RSTSTA); - UART_PUT_IDR(port, ATMEL_US_RXBRK); - atmel_port->break_active = 0; - } - - // TODO: All reads to CSR will clear these interrupts! - if (pending & ATMEL_US_RIIC) port->icount.rng++; - if (pending & ATMEL_US_DSRIC) port->icount.dsr++; - if (pending & ATMEL_US_DCDIC) - uart_handle_dcd_change(port, !(status & ATMEL_US_DCD)); - if (pending & ATMEL_US_CTSIC) - uart_handle_cts_change(port, !(status & ATMEL_US_CTS)); - if (pending & (ATMEL_US_RIIC | ATMEL_US_DSRIC | ATMEL_US_DCDIC | ATMEL_US_CTSIC)) - wake_up_interruptible(&port->info->delta_msr_wait); - - /* Interrupt transmit */ - if (pending & ATMEL_US_TXRDY) - atmel_tx_chars(port); + atmel_handle_receive(port, pending); + atmel_handle_status(port, pending, status); + atmel_handle_transmit(port, pending); if (pass_counter++ > ATMEL_ISR_PASS_LIMIT) break; @@ -414,7 +443,8 @@ static int atmel_startup(struct uart_port *port) /* * Allocate the IRQ */ - retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED, "atmel_serial", port); + retval = request_irq(port->irq, atmel_interrupt, IRQF_SHARED, + "atmel_serial", port); if (retval) { printk("atmel_serial: atmel_startup - Can't get irq\n"); return retval; @@ -436,9 +466,11 @@ static int atmel_startup(struct uart_port *port) * Finally, enable the serial port */ UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX); - UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN); /* enable xmit & rcvr */ + /* enable xmit & rcvr */ + UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN); - UART_PUT_IER(port, ATMEL_US_RXRDY); /* enable receive only */ + /* enable receive only */ + UART_PUT_IER(port, ATMEL_US_RXRDY); return 0; } @@ -470,45 +502,48 @@ static void atmel_shutdown(struct uart_port *port) /* * Power / Clock management. */ -static void atmel_serial_pm(struct uart_port *port, unsigned int state, unsigned int oldstate) +static void atmel_serial_pm(struct uart_port *port, unsigned int state, + unsigned int oldstate) { - struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port; + struct atmel_uart_port *atmel_port = (struct atmel_uart_port *)port; switch (state) { - case 0: - /* - * Enable the peripheral clock for this serial port. - * This is called on uart_open() or a resume event. - */ - clk_enable(atmel_port->clk); - break; - case 3: - /* - * Disable the peripheral clock for this serial port. - * This is called on uart_close() or a suspend event. - */ - clk_disable(atmel_port->clk); - break; - default: - printk(KERN_ERR "atmel_serial: unknown pm %d\n", state); + case 0: + /* + * Enable the peripheral clock for this serial port. + * This is called on uart_open() or a resume event. + */ + clk_enable(atmel_port->clk); + break; + case 3: + /* + * Disable the peripheral clock for this serial port. + * This is called on uart_close() or a suspend event. + */ + clk_disable(atmel_port->clk); + break; + default: + printk(KERN_ERR "atmel_serial: unknown pm %d\n", state); } } /* * Change the port parameters */ -static void atmel_set_termios(struct uart_port *port, struct ktermios * termios, struct ktermios * old) +static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) { unsigned long flags; unsigned int mode, imr, quot, baud; /* Get current mode register */ - mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL | ATMEL_US_NBSTOP | ATMEL_US_PAR); + mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL + | ATMEL_US_NBSTOP | ATMEL_US_PAR); - baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); quot = uart_get_divisor(port, baud); - if (quot > 65535) { /* BRGR is 16-bit, so switch to slower clock */ + if (quot > 65535) { /* BRGR is 16-bit, so switch to slower clock */ quot /= 8; mode |= ATMEL_US_USCLKS_MCK_DIV8; } @@ -535,18 +570,17 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios * termios, /* parity */ if (termios->c_cflag & PARENB) { - if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */ + /* Mark or Space parity */ + if (termios->c_cflag & CMSPAR) { if (termios->c_cflag & PARODD) mode |= ATMEL_US_PAR_MARK; else mode |= ATMEL_US_PAR_SPACE; - } - else if (termios->c_cflag & PARODD) + } else if (termios->c_cflag & PARODD) mode |= ATMEL_US_PAR_ODD; else mode |= ATMEL_US_PAR_EVEN; - } - else + } else mode |= ATMEL_US_PAR_NONE; spin_lock_irqsave(&port->lock, flags); @@ -572,16 +606,16 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios * termios, if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= ATMEL_US_OVRE; } - - // TODO: Ignore all characters if CREAD is set. + /* TODO: Ignore all characters if CREAD is set.*/ /* update the per-port timeout */ uart_update_timeout(port, termios->c_cflag, baud); - /* disable interrupts and drain transmitter */ - imr = UART_GET_IMR(port); /* get interrupt mask */ - UART_PUT_IDR(port, -1); /* disable all interrupts */ - while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY)) { barrier(); } + /* save/disable interrupts and drain transmitter */ + imr = UART_GET_IMR(port); + UART_PUT_IDR(port, -1); + while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY)) + barrier(); /* disable receiver and transmitter */ UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS); @@ -707,7 +741,8 @@ static struct uart_ops atmel_pops = { /* * Configure the port from the platform device resource info. */ -static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port, struct platform_device *pdev) +static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port, + struct platform_device *pdev) { struct uart_port *port = &atmel_port->uart; struct atmel_uart_data *data = pdev->dev.platform_data; @@ -730,7 +765,8 @@ static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port, struct port->membase = NULL; } - if (!atmel_port->clk) { /* for console, the clock could already be configured */ + /* for console, the clock could already be configured */ + if (!atmel_port->clk) { atmel_port->clk = clk_get(&pdev->dev, "usart"); clk_enable(atmel_port->clk); port->uartclk = clk_get_rate(atmel_port->clk); @@ -754,7 +790,6 @@ void __init atmel_register_uart_fns(struct atmel_port_fns *fns) atmel_pops.set_wake = fns->set_wake; } - #ifdef CONFIG_SERIAL_ATMEL_CONSOLE static void atmel_console_putchar(struct uart_port *port, int ch) { @@ -772,28 +807,30 @@ static void atmel_console_write(struct console *co, const char *s, u_int count) unsigned int status, imr; /* - * First, save IMR and then disable interrupts + * First, save IMR and then disable interrupts */ - imr = UART_GET_IMR(port); /* get interrupt mask */ + imr = UART_GET_IMR(port); UART_PUT_IDR(port, ATMEL_US_RXRDY | ATMEL_US_TXRDY); uart_console_write(port, s, count, atmel_console_putchar); /* - * Finally, wait for transmitter to become empty - * and restore IMR + * Finally, wait for transmitter to become empty + * and restore IMR */ do { status = UART_GET_CSR(port); } while (!(status & ATMEL_US_TXRDY)); - UART_PUT_IER(port, imr); /* set interrupts back the way they were */ + /* set interrupts back the way they were */ + UART_PUT_IER(port, imr); } /* - * If the port was already initialised (eg, by a boot loader), try to determine - * the current setup. + * If the port was already initialised (eg, by a boot loader), + * try to determine the current setup. */ -static void __init atmel_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits) +static void __init atmel_console_get_options(struct uart_port *port, int *baud, + int *parity, int *bits) { unsigned int mr, quot; @@ -835,10 +872,12 @@ static int __init atmel_console_setup(struct console *co, char *options) int parity = 'n'; int flow = 'n'; - if (port->membase == 0) /* Port not initialized yet - delay setup */ + if (port->membase == NULL) { + /* Port not initialized yet - delay setup */ return -ENODEV; + } - UART_PUT_IDR(port, -1); /* disable interrupts */ + UART_PUT_IDR(port, -1); UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX); UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN); @@ -870,13 +909,16 @@ static struct console atmel_console = { static int __init atmel_console_init(void) { if (atmel_default_console_device) { - add_preferred_console(ATMEL_DEVICENAME, atmel_default_console_device->id, NULL); - atmel_init_port(&(atmel_ports[atmel_default_console_device->id]), atmel_default_console_device); + add_preferred_console(ATMEL_DEVICENAME, + atmel_default_console_device->id, NULL); + atmel_init_port(&atmel_ports[atmel_default_console_device->id], + atmel_default_console_device); register_console(&atmel_console); } return 0; } + console_initcall(atmel_console_init); /* @@ -884,11 +926,13 @@ console_initcall(atmel_console_init); */ static int __init atmel_late_console_init(void) { - if (atmel_default_console_device && !(atmel_console.flags & CON_ENABLED)) + if (atmel_default_console_device + && !(atmel_console.flags & CON_ENABLED)) register_console(&atmel_console); return 0; } + core_initcall(atmel_late_console_init); #else @@ -896,22 +940,24 @@ core_initcall(atmel_late_console_init); #endif static struct uart_driver atmel_uart = { - .owner = THIS_MODULE, - .driver_name = "atmel_serial", - .dev_name = ATMEL_DEVICENAME, - .major = SERIAL_ATMEL_MAJOR, - .minor = MINOR_START, - .nr = ATMEL_MAX_UART, - .cons = ATMEL_CONSOLE_DEVICE, + .owner = THIS_MODULE, + .driver_name = "atmel_serial", + .dev_name = ATMEL_DEVICENAME, + .major = SERIAL_ATMEL_MAJOR, + .minor = MINOR_START, + .nr = ATMEL_MAX_UART, + .cons = ATMEL_CONSOLE_DEVICE, }; #ifdef CONFIG_PM -static int atmel_serial_suspend(struct platform_device *pdev, pm_message_t state) +static int atmel_serial_suspend(struct platform_device *pdev, + pm_message_t state) { struct uart_port *port = platform_get_drvdata(pdev); - struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port; + struct atmel_uart_port *atmel_port = (struct atmel_uart_port *)port; - if (device_may_wakeup(&pdev->dev) && !at91_suspend_entering_slow_clock()) + if (device_may_wakeup(&pdev->dev) + && !at91_suspend_entering_slow_clock()) enable_irq_wake(port->irq); else { uart_suspend_port(&atmel_uart, port); @@ -924,13 +970,12 @@ static int atmel_serial_suspend(struct platform_device *pdev, pm_message_t state static int atmel_serial_resume(struct platform_device *pdev) { struct uart_port *port = platform_get_drvdata(pdev); - struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port; + struct atmel_uart_port *atmel_port = (struct atmel_uart_port *)port; if (atmel_port->suspended) { uart_resume_port(&atmel_uart, port); atmel_port->suspended = 0; - } - else + } else disable_irq_wake(port->irq); return 0; @@ -960,7 +1005,7 @@ static int __devinit atmel_serial_probe(struct platform_device *pdev) static int __devexit atmel_serial_remove(struct platform_device *pdev) { struct uart_port *port = platform_get_drvdata(pdev); - struct atmel_uart_port *atmel_port = (struct atmel_uart_port *) port; + struct atmel_uart_port *atmel_port = (struct atmel_uart_port *)port; int ret = 0; clk_disable(atmel_port->clk); |