serial: st-asc: Read in all Pinctrl states

There are now 2 possible separate/different Pinctrl states which can
be provided from platform data.  One which encompasses the lines
required for HW flow-control (CTS/RTS) and another which does not
specify these lines, such that they can be used via GPIO mechanisms
for manually toggling (i.e. from a request by `stty`).

Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index 397df507579e943edb72e53358b7f473b5a6a9bf..105802099e47e9a19abd26902d47128f21d2509b 100644 (file)
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -18,6 +18,7 @@
 #include <linux/serial.h>
 #include <linux/console.h>
 #include <linux/sysrq.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -37,10 +38,16 @@
 #define ASC_FIFO_SIZE 16
 #define ASC_MAX_PORTS 8
 
+/* Pinctrl states */
+#define DEFAULT                0
+#define NO_HW_FLOWCTRL 1
+
 struct asc_port {
        struct uart_port port;
        struct gpio_desc *rts;
        struct clk *clk;
+       struct pinctrl *pinctrl;
+       struct pinctrl_state *states[2];
        unsigned int hw_flow_control:1;
        unsigned int force_m1:1;
 };
@@ -694,6 +701,7 @@ static int asc_init_port(struct asc_port *ascport,
 {
        struct uart_port *port = &ascport->port;
        struct resource *res;
+       int ret;
 
        port->iotype    = UPIO_MEM;
        port->flags     = UPF_BOOT_AUTOCONF;
@@ -720,6 +728,27 @@ static int asc_init_port(struct asc_port *ascport,
        WARN_ON(ascport->port.uartclk == 0);
        clk_disable_unprepare(ascport->clk);
 
+       ascport->pinctrl = devm_pinctrl_get(&pdev->dev);
+       if (IS_ERR(ascport->pinctrl)) {
+               ret = PTR_ERR(ascport->pinctrl);
+               dev_err(&pdev->dev, "Failed to get Pinctrl: %d\n", ret);
+       }
+
+       ascport->states[DEFAULT] =
+               pinctrl_lookup_state(ascport->pinctrl, "default");
+       if (IS_ERR(ascport->states[DEFAULT])) {
+               ret = PTR_ERR(ascport->states[DEFAULT]);
+               dev_err(&pdev->dev,
+                       "Failed to look up Pinctrl state 'default': %d\n", ret);
+               return ret;
+       }
+
+       /* "no-hw-flowctrl" state is optional */
+       ascport->states[NO_HW_FLOWCTRL] =
+               pinctrl_lookup_state(ascport->pinctrl, "no-hw-flowctrl");
+       if (IS_ERR(ascport->states[NO_HW_FLOWCTRL]))
+               ascport->states[NO_HW_FLOWCTRL] = NULL;
+
        return 0;
 }