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path: root/drivers/tty/serial/imx.c
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Diffstat (limited to 'drivers/tty/serial/imx.c')
-rw-r--r--drivers/tty/serial/imx.c148
1 files changed, 133 insertions, 15 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 163fc9021f5..0b7fed746b2 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)
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 11:22:50 +0000