diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
-rw-r--r-- | drivers/tty/serial/imx.c | 148 |
1 files changed, 133 insertions, 15 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 163fc9021f5a..0b7fed746b27 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -102,6 +102,7 @@ #define UCR2_STPB (1<<6) /* Stop */ #define UCR2_WS (1<<5) /* Word size */ #define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */ +#define UCR2_ATEN (1<<3) /* Aging Timer Enable */ #define UCR2_TXEN (1<<2) /* Transmitter enabled */ #define UCR2_RXEN (1<<1) /* Receiver enabled */ #define UCR2_SRST (1<<0) /* SW reset */ @@ -207,6 +208,12 @@ struct imx_port { struct imx_uart_data *devdata; }; +struct imx_port_ucrs { + unsigned int ucr1; + unsigned int ucr2; + unsigned int ucr3; +}; + #ifdef CONFIG_IRDA #define USE_IRDA(sport) ((sport)->use_irda) #else @@ -260,6 +267,27 @@ static inline int is_imx21_uart(struct imx_port *sport) } /* + * Save and restore functions for UCR1, UCR2 and UCR3 registers + */ +static void imx_port_ucrs_save(struct uart_port *port, + struct imx_port_ucrs *ucr) +{ + /* save control registers */ + ucr->ucr1 = readl(port->membase + UCR1); + ucr->ucr2 = readl(port->membase + UCR2); + ucr->ucr3 = readl(port->membase + UCR3); +} + +static void imx_port_ucrs_restore(struct uart_port *port, + struct imx_port_ucrs *ucr) +{ + /* restore control registers */ + writel(ucr->ucr1, port->membase + UCR1); + writel(ucr->ucr2, port->membase + UCR2); + writel(ucr->ucr3, port->membase + UCR3); +} + +/* * Handle any change of modem status signal since we were last called. */ static void imx_mctrl_check(struct imx_port *sport) @@ -566,6 +594,9 @@ static irqreturn_t imx_int(int irq, void *dev_id) if (sts & USR1_RTSD) imx_rtsint(irq, dev_id); + if (sts & USR1_AWAKE) + writel(USR1_AWAKE, sport->port.membase + USR1); + return IRQ_HANDLED; } @@ -901,6 +932,8 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, ucr2 |= UCR2_PROE; } + del_timer_sync(&sport->timer); + /* * Ask the core to calculate the divisor for us. */ @@ -931,8 +964,6 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, sport->port.ignore_status_mask |= URXD_OVRRUN; } - del_timer_sync(&sport->timer); - /* * Update the per-port timeout. */ @@ -1079,6 +1110,70 @@ imx_verify_port(struct uart_port *port, struct serial_struct *ser) return ret; } +#if defined(CONFIG_CONSOLE_POLL) +static int imx_poll_get_char(struct uart_port *port) +{ + struct imx_port_ucrs old_ucr; + unsigned int status; + unsigned char c; + + /* save control registers */ + imx_port_ucrs_save(port, &old_ucr); + + /* disable interrupts */ + writel(UCR1_UARTEN, port->membase + UCR1); + writel(old_ucr.ucr2 & ~(UCR2_ATEN | UCR2_RTSEN | UCR2_ESCI), + port->membase + UCR2); + writel(old_ucr.ucr3 & ~(UCR3_DCD | UCR3_RI | UCR3_DTREN), + port->membase + UCR3); + + /* poll */ + do { + status = readl(port->membase + USR2); + } while (~status & USR2_RDR); + + /* read */ + c = readl(port->membase + URXD0); + + /* restore control registers */ + imx_port_ucrs_restore(port, &old_ucr); + + return c; +} + +static void imx_poll_put_char(struct uart_port *port, unsigned char c) +{ + struct imx_port_ucrs old_ucr; + unsigned int status; + + /* save control registers */ + imx_port_ucrs_save(port, &old_ucr); + + /* disable interrupts */ + writel(UCR1_UARTEN, port->membase + UCR1); + writel(old_ucr.ucr2 & ~(UCR2_ATEN | UCR2_RTSEN | UCR2_ESCI), + port->membase + UCR2); + writel(old_ucr.ucr3 & ~(UCR3_DCD | UCR3_RI | UCR3_DTREN), + port->membase + UCR3); + + /* drain */ + do { + status = readl(port->membase + USR1); + } while (~status & USR1_TRDY); + + /* write */ + writel(c, port->membase + URTX0); + + /* flush */ + do { + status = readl(port->membase + USR2); + } while (~status & USR2_TXDC); + + /* restore control registers */ + imx_port_ucrs_restore(port, &old_ucr); +} +#endif + static struct uart_ops imx_pops = { .tx_empty = imx_tx_empty, .set_mctrl = imx_set_mctrl, @@ -1096,6 +1191,10 @@ static struct uart_ops imx_pops = { .request_port = imx_request_port, .config_port = imx_config_port, .verify_port = imx_verify_port, +#if defined(CONFIG_CONSOLE_POLL) + .poll_get_char = imx_poll_get_char, + .poll_put_char = imx_poll_put_char, +#endif }; static struct imx_port *imx_ports[UART_NR]; @@ -1118,13 +1217,14 @@ static void imx_console_write(struct console *co, const char *s, unsigned int count) { struct imx_port *sport = imx_ports[co->index]; - unsigned int old_ucr1, old_ucr2, ucr1; + struct imx_port_ucrs old_ucr; + unsigned int ucr1; /* - * First, save UCR1/2 and then disable interrupts + * First, save UCR1/2/3 and then disable interrupts */ - ucr1 = old_ucr1 = readl(sport->port.membase + UCR1); - old_ucr2 = readl(sport->port.membase + UCR2); + imx_port_ucrs_save(&sport->port, &old_ucr); + ucr1 = old_ucr.ucr1; if (is_imx1_uart(sport)) ucr1 |= IMX1_UCR1_UARTCLKEN; @@ -1133,18 +1233,17 @@ imx_console_write(struct console *co, const char *s, unsigned int count) writel(ucr1, sport->port.membase + UCR1); - writel(old_ucr2 | UCR2_TXEN, sport->port.membase + UCR2); + writel(old_ucr.ucr2 | UCR2_TXEN, sport->port.membase + UCR2); uart_console_write(&sport->port, s, count, imx_console_putchar); /* * Finally, wait for transmitter to become empty - * and restore UCR1/2 + * and restore UCR1/2/3 */ while (!(readl(sport->port.membase + USR2) & USR2_TXDC)); - writel(old_ucr1, sport->port.membase + UCR1); - writel(old_ucr2, sport->port.membase + UCR2); + imx_port_ucrs_restore(&sport->port, &old_ucr); } /* @@ -1269,6 +1368,12 @@ static struct uart_driver imx_reg = { static int serial_imx_suspend(struct platform_device *dev, pm_message_t state) { struct imx_port *sport = platform_get_drvdata(dev); + unsigned int val; + + /* enable wakeup from i.MX UART */ + val = readl(sport->port.membase + UCR3); + val |= UCR3_AWAKEN; + writel(val, sport->port.membase + UCR3); if (sport) uart_suspend_port(&imx_reg, &sport->port); @@ -1279,6 +1384,12 @@ static int serial_imx_suspend(struct platform_device *dev, pm_message_t state) static int serial_imx_resume(struct platform_device *dev) { struct imx_port *sport = platform_get_drvdata(dev); + unsigned int val; + + /* disable wakeup from i.MX UART */ + val = readl(sport->port.membase + UCR3); + val &= ~UCR3_AWAKEN; + writel(val, sport->port.membase + UCR3); if (sport) uart_resume_port(&imx_reg, &sport->port); @@ -1287,6 +1398,10 @@ static int serial_imx_resume(struct platform_device *dev) } #ifdef CONFIG_OF +/* + * This function returns 1 iff pdev isn't a device instatiated by dt, 0 iff it + * could successfully get all information from dt or a negative errno. + */ static int serial_imx_probe_dt(struct imx_port *sport, struct platform_device *pdev) { @@ -1296,12 +1411,13 @@ static int serial_imx_probe_dt(struct imx_port *sport, int ret; if (!np) - return -ENODEV; + /* no device tree device */ + return 1; ret = of_alias_get_id(np, "serial"); if (ret < 0) { dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret); - return -ENODEV; + return ret; } sport->port.line = ret; @@ -1319,7 +1435,7 @@ static int serial_imx_probe_dt(struct imx_port *sport, static inline int serial_imx_probe_dt(struct imx_port *sport, struct platform_device *pdev) { - return -ENODEV; + return 1; } #endif @@ -1354,8 +1470,10 @@ static int serial_imx_probe(struct platform_device *pdev) return -ENOMEM; ret = serial_imx_probe_dt(sport, pdev); - if (ret == -ENODEV) + if (ret > 0) serial_imx_probe_pdata(sport, pdev); + else if (ret < 0) + goto free; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { @@ -1476,7 +1594,7 @@ static int __init imx_serial_init(void) if (ret != 0) uart_unregister_driver(&imx_reg); - return 0; + return ret; } static void __exit imx_serial_exit(void) |