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path: root/drivers/serial/imx.c
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Diffstat (limited to 'drivers/serial/imx.c')
-rw-r--r--drivers/serial/imx.c294
1 files changed, 229 insertions, 65 deletions
diff --git a/drivers/serial/imx.c b/drivers/serial/imx.c
index 5f0be40dfdab..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
@@ -1072,22 +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)
@@ -1143,19 +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);
@@ -1193,13 +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,
},
};