[COMMON] serial: samsung: Add pinctrl fucntion.

For some devices like Bluetooth, RTS line should be protected
while suspending or SICD in and out in case of unexpected data
flow.

Change-Id: I42fb8c3009c4642b0f5fb74e18e8a6151e5b3b3f
Signed-off-by: Kyungwoo Kang <kwoo.kang@samsung.com>

diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 3df8070c37a07b19bf1a7541f752caada38c5f22..b8e98d27d4ee6f692df7eff5b3ab94420e4f425c 100644 (file)
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -106,6 +106,30 @@ EXPORT_SYMBOL_GPL(s3c2410_serial_wake_peer);
 #define UART_LOOPBACK_MODE     (0x1 << 0)
 #define UART_DBG_MODE          (0x1 << 1)
 
+#define RTS_PINCTRL                    (1)
+#define DEFAULT_PINCTRL                (0)
+
+static void change_uart_gpio(int value, struct s3c24xx_uart_port *ourport)
+{
+       int status = 0;
+
+       if (value) {
+               if (!IS_ERR(ourport->uart_pinctrl_rts)) {
+                       ourport->default_uart_pinctrl->state = NULL;
+                       status = pinctrl_select_state(ourport->default_uart_pinctrl, ourport->uart_pinctrl_rts);
+                       if (status)
+                               dev_err(ourport->port.dev, "Can't set RTS uart pins!!!\n");
+               }
+       } else {
+               if (!IS_ERR(ourport->uart_pinctrl_default)) {
+                       ourport->default_uart_pinctrl->state = NULL;
+                       status = pinctrl_select_state(ourport->default_uart_pinctrl, ourport->uart_pinctrl_default);
+                       if (status)
+                               dev_err(ourport->port.dev, "Can't set default uart pins!!!\n");
+               }
+       }
+}
+
 static void print_uart_mode(struct uart_port *port,
                struct ktermios *termios, unsigned int baud)
 {
@@ -1016,6 +1040,7 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
                port->ignore_status_mask |= RXSTAT_DUMMY_READ;
 
        spin_unlock_irqrestore(&port->lock, flags);
+
 }
 
 static const char *s3c24xx_serial_type(struct uart_port *port)
@@ -1522,6 +1547,9 @@ static int s3c24xx_serial_notifier(struct notifier_block *self,
                        wr_regl(port, S3C2410_UMCON, umcon);
 
                        spin_unlock_irqrestore(&port->lock, flags);
+
+                       if (ourport->rts_control)
+                               change_uart_gpio(RTS_PINCTRL, ourport);
                }
                break;
 
@@ -1544,6 +1572,9 @@ static int s3c24xx_serial_notifier(struct notifier_block *self,
                        wr_regl(port, S3C2410_UMCON, umcon);
 
                        spin_unlock_irqrestore(&port->lock, flags);
+
+                       if (ourport->rts_control)
+                               change_uart_gpio(DEFAULT_PINCTRL, ourport);
                }
                break;
 
@@ -1610,6 +1641,24 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
        else
                ourport->usi_v2 = 0;
 
+       if (of_get_property(pdev->dev.of_node, "samsung,rts-gpio-control", NULL)) {
+               ourport->rts_control = 1;
+               ourport->default_uart_pinctrl = devm_pinctrl_get(&pdev->dev);
+               if (IS_ERR(ourport->default_uart_pinctrl))
+                       dev_err(&pdev->dev, "Can't get uart pinctrl!!!\n");
+               else {
+                       ourport->uart_pinctrl_rts = pinctrl_lookup_state(ourport->default_uart_pinctrl,
+                                               "rts");
+                       if (IS_ERR(ourport->uart_pinctrl_rts))
+                               dev_err(&pdev->dev, "Can't get RTS pinstate!!!\n");
+
+                       ourport->uart_pinctrl_default = pinctrl_lookup_state(ourport->default_uart_pinctrl,
+                                               "default");
+                       if (IS_ERR(ourport->uart_pinctrl_default))
+                               dev_err(&pdev->dev, "Can't get Default pinstate!!!\n");
+               }
+       }
+
        if (!of_property_read_u32(pdev->dev.of_node, "samsung,fifo-size",
                                &fifo_size)) {
                ourport->port.fifosize = fifo_size;
@@ -1734,12 +1783,19 @@ static int s3c24xx_serial_suspend(struct device *dev)
 #endif
 
        if (port) {
+               /*
+                * If rts line must be protected while suspending
+                * we change the gpio pad as output high
+               */
+               if (ourport->rts_control)
+                       change_uart_gpio(RTS_PINCTRL, ourport);
+
                uart_suspend_port(&s3c24xx_uart_drv, port);
 #ifdef CONFIG_SERIAL_SAMSUNG_HWACG
                uart_clock_enable(ourport);
                /* disable Tx, Rx mode bit for suspend in case of HWACG */
                ucon = rd_regl(port, S3C2410_UCON);
-               ucon &= ~(S3C2410_UCON_RXIRQMODE | S3C2410_UCON_TXIRQMODE) ;
+               ucon &= ~(S3C2410_UCON_RXIRQMODE | S3C2410_UCON_TXIRQMODE);
                wr_regl(port, S3C2410_UCON, ucon);
                exynos_usi_stop(port);
                uart_clock_disable(ourport);
@@ -1766,6 +1822,10 @@ static int s3c24xx_serial_resume(struct device *dev)
                uart_clock_disable(ourport);
 
                uart_resume_port(&s3c24xx_uart_drv, port);
+
+               if (ourport->rts_control)
+                       change_uart_gpio(DEFAULT_PINCTRL, ourport);
+
                if (ourport->dbg_mode & UART_DBG_MODE)
                        dev_err(dev, "UART resume notification for tty framework.\n");
        }
@@ -1782,6 +1842,7 @@ static int s3c24xx_serial_resume_noirq(struct device *dev)
                /* restore IRQ mask */
                if (s3c24xx_serial_has_interrupt_mask(port)) {
                        unsigned int uintm = 0xf;
+
                        if (tx_enabled(port))
                                uintm &= ~S3C64XX_UINTM_TXD_MSK;
                        if (rx_enabled(port))

diff --git a/drivers/tty/serial/samsung.h b/drivers/tty/serial/samsung.h
index bba203233f53790c15213a8e8df24be69b8260c4..a60bf514878d7a6615485f874c9611cfdc0ab17f 100644 (file)
--- a/drivers/tty/serial/samsung.h
+++ b/drivers/tty/serial/samsung.h
@@ -73,6 +73,10 @@ struct s3c24xx_uart_port {
        u32                             use_default_irq;
        unsigned long                   qos_timeout;
        unsigned int                    usi_v2;
+       struct pinctrl_state    *uart_pinctrl_rts;
+       struct pinctrl_state    *uart_pinctrl_default;
+       struct pinctrl *default_uart_pinctrl;
+       unsigned int            rts_control;
 
        /* reference to platform data */
        struct s3c2410_uartcfg          *cfg;
@@ -85,6 +89,7 @@ struct s3c24xx_uart_port {
 
        unsigned int                    in_band_wakeup;
        unsigned int dbg_mode;
+
 };
 
 /* conversion functions */