diff options
Diffstat (limited to 'drivers/serial/imx.c')
-rw-r--r-- | drivers/serial/imx.c | 296 |
1 files changed, 231 insertions, 65 deletions
diff --git a/drivers/serial/imx.c b/drivers/serial/imx.c index 9f460b175c50..7b5d1de9cfe3 100644 --- a/drivers/serial/imx.c +++ b/drivers/serial/imx.c @@ -8,6 +8,9 @@ * Author: Sascha Hauer <sascha@saschahauer.de> * Copyright (C) 2004 Pengutronix * + * Copyright (C) 2009 emlix GmbH + * Author: Fabian Godehardt (added IrDA support for iMX) + * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or @@ -41,6 +44,8 @@ #include <linux/serial_core.h> #include <linux/serial.h> #include <linux/clk.h> +#include <linux/delay.h> +#include <linux/rational.h> #include <asm/io.h> #include <asm/irq.h> @@ -148,6 +153,7 @@ #define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */ #define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */ #define UFCR_RFDIV (7<<7) /* Reference freq divider mask */ +#define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7) #define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */ #define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */ #define USR1_RTSS (1<<14) /* RTS pin status */ @@ -211,10 +217,20 @@ struct imx_port { struct timer_list timer; unsigned int old_status; int txirq,rxirq,rtsirq; - int have_rtscts:1; + unsigned int have_rtscts:1; + unsigned int use_irda:1; + unsigned int irda_inv_rx:1; + unsigned int irda_inv_tx:1; + unsigned short trcv_delay; /* transceiver delay */ struct clk *clk; }; +#ifdef CONFIG_IRDA +#define USE_IRDA(sport) ((sport)->use_irda) +#else +#define USE_IRDA(sport) (0) +#endif + /* * Handle any change of modem status signal since we were last called. */ @@ -268,6 +284,48 @@ static void imx_stop_tx(struct uart_port *port) struct imx_port *sport = (struct imx_port *)port; unsigned long temp; + if (USE_IRDA(sport)) { + /* half duplex - wait for end of transmission */ + int n = 256; + while ((--n > 0) && + !(readl(sport->port.membase + USR2) & USR2_TXDC)) { + udelay(5); + barrier(); + } + /* + * irda transceiver - wait a bit more to avoid + * cutoff, hardware dependent + */ + udelay(sport->trcv_delay); + + /* + * half duplex - reactivate receive mode, + * flush receive pipe echo crap + */ + if (readl(sport->port.membase + USR2) & USR2_TXDC) { + temp = readl(sport->port.membase + UCR1); + temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN); + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR4); + temp &= ~(UCR4_TCEN); + writel(temp, sport->port.membase + UCR4); + + while (readl(sport->port.membase + URXD0) & + URXD_CHARRDY) + barrier(); + + temp = readl(sport->port.membase + UCR1); + temp |= UCR1_RRDYEN; + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR4); + temp |= UCR4_DREN; + writel(temp, sport->port.membase + UCR4); + } + return; + } + temp = readl(sport->port.membase + UCR1); writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1); } @@ -302,13 +360,15 @@ static inline void imx_transmit_buffer(struct imx_port *sport) /* send xmit->buf[xmit->tail] * out the port here */ writel(xmit->buf[xmit->tail], sport->port.membase + URTX0); - xmit->tail = (xmit->tail + 1) & - (UART_XMIT_SIZE - 1); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); sport->port.icount.tx++; if (uart_circ_empty(xmit)) break; } + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(&sport->port); + if (uart_circ_empty(xmit)) imx_stop_tx(&sport->port); } @@ -321,9 +381,30 @@ static void imx_start_tx(struct uart_port *port) struct imx_port *sport = (struct imx_port *)port; unsigned long temp; + if (USE_IRDA(sport)) { + /* half duplex in IrDA mode; have to disable receive mode */ + temp = readl(sport->port.membase + UCR4); + temp &= ~(UCR4_DREN); + writel(temp, sport->port.membase + UCR4); + + temp = readl(sport->port.membase + UCR1); + temp &= ~(UCR1_RRDYEN); + writel(temp, sport->port.membase + UCR1); + } + temp = readl(sport->port.membase + UCR1); writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1); + if (USE_IRDA(sport)) { + temp = readl(sport->port.membase + UCR1); + temp |= UCR1_TRDYEN; + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR4); + temp |= UCR4_TCEN; + writel(temp, sport->port.membase + UCR4); + } + if (readl(sport->port.membase + UTS) & UTS_TXEMPTY) imx_transmit_buffer(sport); } @@ -395,8 +476,7 @@ static irqreturn_t imx_rxint(int irq, void *dev_id) continue; } - if (uart_handle_sysrq_char - (&sport->port, (unsigned char)rx)) + if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx)) continue; if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) { @@ -471,26 +551,26 @@ static unsigned int imx_tx_empty(struct uart_port *port) */ static unsigned int imx_get_mctrl(struct uart_port *port) { - struct imx_port *sport = (struct imx_port *)port; - unsigned int tmp = TIOCM_DSR | TIOCM_CAR; + struct imx_port *sport = (struct imx_port *)port; + unsigned int tmp = TIOCM_DSR | TIOCM_CAR; - if (readl(sport->port.membase + USR1) & USR1_RTSS) - tmp |= TIOCM_CTS; + if (readl(sport->port.membase + USR1) & USR1_RTSS) + tmp |= TIOCM_CTS; - if (readl(sport->port.membase + UCR2) & UCR2_CTS) - tmp |= TIOCM_RTS; + if (readl(sport->port.membase + UCR2) & UCR2_CTS) + tmp |= TIOCM_RTS; - return tmp; + return tmp; } static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl) { - struct imx_port *sport = (struct imx_port *)port; + struct imx_port *sport = (struct imx_port *)port; unsigned long temp; temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS; - if (mctrl & TIOCM_RTS) + if (mctrl & TIOCM_RTS) temp |= UCR2_CTS; writel(temp, sport->port.membase + UCR2); @@ -534,12 +614,7 @@ static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode) if(!ufcr_rfdiv) ufcr_rfdiv = 1; - if(ufcr_rfdiv >= 7) - ufcr_rfdiv = 6; - else - ufcr_rfdiv = 6 - ufcr_rfdiv; - - val |= UFCR_RFDIV & (ufcr_rfdiv << 7); + val |= UFCR_RFDIV_REG(ufcr_rfdiv); writel(val, sport->port.membase + UFCR); @@ -558,8 +633,24 @@ static int imx_startup(struct uart_port *port) * requesting IRQs */ temp = readl(sport->port.membase + UCR4); + + if (USE_IRDA(sport)) + temp |= UCR4_IRSC; + writel(temp & ~UCR4_DREN, sport->port.membase + UCR4); + if (USE_IRDA(sport)) { + /* reset fifo's and state machines */ + int i = 100; + temp = readl(sport->port.membase + UCR2); + temp &= ~UCR2_SRST; + writel(temp, sport->port.membase + UCR2); + while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) && + (--i > 0)) { + udelay(1); + } + } + /* * Allocate the IRQ(s) i.MX1 has three interrupts whereas later * chips only have one interrupt. @@ -575,12 +666,16 @@ static int imx_startup(struct uart_port *port) if (retval) goto error_out2; - retval = request_irq(sport->rtsirq, imx_rtsint, - (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 : - IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING, - DRIVER_NAME, sport); - if (retval) - goto error_out3; + /* do not use RTS IRQ on IrDA */ + if (!USE_IRDA(sport)) { + retval = request_irq(sport->rtsirq, imx_rtsint, + (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 : + IRQF_TRIGGER_FALLING | + IRQF_TRIGGER_RISING, + DRIVER_NAME, sport); + if (retval) + goto error_out3; + } } else { retval = request_irq(sport->port.irq, imx_int, 0, DRIVER_NAME, sport); @@ -597,18 +692,49 @@ static int imx_startup(struct uart_port *port) temp = readl(sport->port.membase + UCR1); temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN; + + if (USE_IRDA(sport)) { + temp |= UCR1_IREN; + temp &= ~(UCR1_RTSDEN); + } + writel(temp, sport->port.membase + UCR1); temp = readl(sport->port.membase + UCR2); temp |= (UCR2_RXEN | UCR2_TXEN); writel(temp, sport->port.membase + UCR2); + if (USE_IRDA(sport)) { + /* clear RX-FIFO */ + int i = 64; + while ((--i > 0) && + (readl(sport->port.membase + URXD0) & URXD_CHARRDY)) { + barrier(); + } + } + #if defined CONFIG_ARCH_MX2 || defined CONFIG_ARCH_MX3 temp = readl(sport->port.membase + UCR3); temp |= UCR3_RXDMUXSEL; writel(temp, sport->port.membase + UCR3); #endif + if (USE_IRDA(sport)) { + temp = readl(sport->port.membase + UCR4); + if (sport->irda_inv_rx) + temp |= UCR4_INVR; + else + temp &= ~(UCR4_INVR); + writel(temp | UCR4_DREN, sport->port.membase + UCR4); + + temp = readl(sport->port.membase + UCR3); + if (sport->irda_inv_tx) + temp |= UCR3_INVT; + else + temp &= ~(UCR3_INVT); + writel(temp, sport->port.membase + UCR3); + } + /* * Enable modem status interrupts */ @@ -616,6 +742,16 @@ static int imx_startup(struct uart_port *port) imx_enable_ms(&sport->port); spin_unlock_irqrestore(&sport->port.lock,flags); + if (USE_IRDA(sport)) { + struct imxuart_platform_data *pdata; + pdata = sport->port.dev->platform_data; + sport->irda_inv_rx = pdata->irda_inv_rx; + sport->irda_inv_tx = pdata->irda_inv_tx; + sport->trcv_delay = pdata->transceiver_delay; + if (pdata->irda_enable) + pdata->irda_enable(1); + } + return 0; error_out3: @@ -633,6 +769,17 @@ static void imx_shutdown(struct uart_port *port) struct imx_port *sport = (struct imx_port *)port; unsigned long temp; + temp = readl(sport->port.membase + UCR2); + temp &= ~(UCR2_TXEN); + writel(temp, sport->port.membase + UCR2); + + if (USE_IRDA(sport)) { + struct imxuart_platform_data *pdata; + pdata = sport->port.dev->platform_data; + if (pdata->irda_enable) + pdata->irda_enable(0); + } + /* * Stop our timer. */ @@ -642,7 +789,8 @@ static void imx_shutdown(struct uart_port *port) * Free the interrupts */ if (sport->txirq > 0) { - free_irq(sport->rtsirq, sport); + if (!USE_IRDA(sport)) + free_irq(sport->rtsirq, sport); free_irq(sport->txirq, sport); free_irq(sport->rxirq, sport); } else @@ -654,6 +802,9 @@ static void imx_shutdown(struct uart_port *port) temp = readl(sport->port.membase + UCR1); temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN); + if (USE_IRDA(sport)) + temp &= ~(UCR1_IREN); + writel(temp, sport->port.membase + UCR1); } @@ -665,7 +816,9 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, unsigned long flags; unsigned int ucr2, old_ucr1, old_txrxen, baud, quot; unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8; - unsigned int div, num, denom, ufcr; + unsigned int div, ufcr; + unsigned long num, denom; + uint64_t tdiv64; /* * If we don't support modem control lines, don't allow @@ -761,38 +914,39 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, sport->port.membase + UCR2); old_txrxen &= (UCR2_TXEN | UCR2_RXEN); - div = sport->port.uartclk / (baud * 16); - if (div > 7) - div = 7; - if (!div) + if (USE_IRDA(sport)) { + /* + * use maximum available submodule frequency to + * avoid missing short pulses due to low sampling rate + */ div = 1; - - num = baud; - denom = port->uartclk / div / 16; - - /* shift num and denom right until they fit into 16 bits */ - while (num > 0x10000 || denom > 0x10000) { - num >>= 1; - denom >>= 1; + } else { + div = sport->port.uartclk / (baud * 16); + if (div > 7) + div = 7; + if (!div) + div = 1; } - if (num > 0) - num -= 1; - if (denom > 0) - denom -= 1; - writel(num, sport->port.membase + UBIR); - writel(denom, sport->port.membase + UBMR); + rational_best_approximation(16 * div * baud, sport->port.uartclk, + 1 << 16, 1 << 16, &num, &denom); - if (div == 7) - div = 6; /* 6 in RFDIV means divide by 7 */ - else - div = 6 - div; + tdiv64 = sport->port.uartclk; + tdiv64 *= num; + do_div(tdiv64, denom * 16 * div); + tty_encode_baud_rate(sport->port.info->port.tty, + (speed_t)tdiv64, (speed_t)tdiv64); + + num -= 1; + denom -= 1; ufcr = readl(sport->port.membase + UFCR); - ufcr = (ufcr & (~UFCR_RFDIV)) | - (div << 7); + ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div); writel(ufcr, sport->port.membase + UFCR); + writel(num, sport->port.membase + UBIR); + writel(denom, sport->port.membase + UBMR); + #ifdef ONEMS writel(sport->port.uartclk / div / 1000, sport->port.membase + ONEMS); #endif @@ -1031,6 +1185,8 @@ imx_console_setup(struct console *co, char *options) if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports)) co->index = 0; sport = imx_ports[co->index]; + if(sport == NULL) + return -ENODEV; if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); @@ -1070,22 +1226,22 @@ 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); + struct imx_port *sport = platform_get_drvdata(dev); - if (sport) - uart_suspend_port(&imx_reg, &sport->port); + if (sport) + uart_suspend_port(&imx_reg, &sport->port); - return 0; + return 0; } static int serial_imx_resume(struct platform_device *dev) { - struct imx_port *sport = platform_get_drvdata(dev); + struct imx_port *sport = platform_get_drvdata(dev); - if (sport) - uart_resume_port(&imx_reg, &sport->port); + if (sport) + uart_resume_port(&imx_reg, &sport->port); - return 0; + return 0; } static int serial_imx_probe(struct platform_device *pdev) @@ -1141,19 +1297,29 @@ static int serial_imx_probe(struct platform_device *pdev) imx_ports[pdev->id] = sport; pdata = pdev->dev.platform_data; - if(pdata && (pdata->flags & IMXUART_HAVE_RTSCTS)) + if (pdata && (pdata->flags & IMXUART_HAVE_RTSCTS)) sport->have_rtscts = 1; +#ifdef CONFIG_IRDA + if (pdata && (pdata->flags & IMXUART_IRDA)) + sport->use_irda = 1; +#endif + if (pdata->init) { ret = pdata->init(pdev); if (ret) goto clkput; } - uart_add_one_port(&imx_reg, &sport->port); + ret = uart_add_one_port(&imx_reg, &sport->port); + if (ret) + goto deinit; platform_set_drvdata(pdev, &sport->port); return 0; +deinit: + if (pdata->exit) + pdata->exit(pdev); clkput: clk_put(sport->clk); clk_disable(sport->clk); @@ -1191,13 +1357,13 @@ static int serial_imx_remove(struct platform_device *pdev) } static struct platform_driver serial_imx_driver = { - .probe = serial_imx_probe, - .remove = serial_imx_remove, + .probe = serial_imx_probe, + .remove = serial_imx_remove, .suspend = serial_imx_suspend, .resume = serial_imx_resume, .driver = { - .name = "imx-uart", + .name = "imx-uart", .owner = THIS_MODULE, }, }; 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