serial: clps711x: Use mctrl_gpio helpers for handling modem signals

CLPS711X serial driver uses the system wide registers to control the
modem signals. Now gpio-syscon driver can be used for this purposes.
mctrl_gpio helpers allow us to create GPIO bindings for any of modem/tty
control signals that extends the functionality of the driver.
This patch makes such change.

This change does not break any current DT bindings, since DT support
for this platform is not introduced yet.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/serial/cirrus,clps711x-uart.txt b/Documentation/devicetree/bindings/serial/cirrus,clps711x-uart.txt
index 12f3cf834debafda85c3b19ce9145eca650f57c6..caaeb2583579ba758bcd31747f47cb3450a2672f 100644 (file)
--- a/Documentation/devicetree/bindings/serial/cirrus,clps711x-uart.txt
+++ b/Documentation/devicetree/bindings/serial/cirrus,clps711x-uart.txt
@@ -8,7 +8,8 @@ Required properties:
 - syscon: Phandle to SYSCON node, which contain UART control bits.
 
 Optional properties:
-- uart-use-ms: Indicate the UART has modem signal (DCD, DSR, CTS).
+- {rts,cts,dtr,dsr,rng,dcd}-gpios: specify a GPIO for RTS/CTS/DTR/DSR/RI/DCD
+  line respectively.
 
 Note: Each UART port should have an alias correctly numbered
 in "aliases" node.
@@ -24,5 +25,7 @@ Example:
                interrupts = <12 13>;
                clocks = <&clks 11>;
                syscon = <&syscon1>;
-               uart-use-ms;
+               cts-gpios = <&sysgpio 0 GPIO_ACTIVE_LOW>;
+               dsr-gpios = <&sysgpio 1 GPIO_ACTIVE_LOW>;
+               dcd-gpios = <&sysgpio 2 GPIO_ACTIVE_LOW>;
        };

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 26cec64dadd7fe25bf9f1569e2fc81077a6bb2f1..75cc59f5d2533c3ea52a442a9a9ddc36bfda456b 100644 (file)
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -204,6 +204,7 @@ config SERIAL_CLPS711X
        tristate "CLPS711X serial port support"
        depends on ARCH_CLPS711X || COMPILE_TEST
        select SERIAL_CORE
+       select SERIAL_MCTRL_GPIO
        help
          This enables the driver for the on-chip UARTs of the Cirrus
          Logic EP711x/EP721x/EP731x processors.

diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c
index f5b4c3d7e38fef6000b21e00b788e4e80d70a578..acfe3177364383da409c9db2fd1d017ab5530b21 100644 (file)
--- a/drivers/tty/serial/clps711x.c
+++ b/drivers/tty/serial/clps711x.c
@@ -33,6 +33,8 @@
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/clps711x.h>
 
+#include "serial_mctrl_gpio.h"
+
 #define UART_CLPS711X_DEVNAME  "ttyCL"
 #define UART_CLPS711X_NR       2
 #define UART_CLPS711X_MAJOR    204
@@ -62,7 +64,7 @@ struct clps711x_port {
        unsigned int            tx_enabled;
        int                     rx_irq;
        struct regmap           *syscon;
-       bool                    use_ms;
+       struct mctrl_gpios      *gpios;
 };
 
 static struct uart_driver clps711x_uart = {
@@ -198,28 +200,17 @@ static unsigned int uart_clps711x_tx_empty(struct uart_port *port)
 
 static unsigned int uart_clps711x_get_mctrl(struct uart_port *port)
 {
+       unsigned int result = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
        struct clps711x_port *s = dev_get_drvdata(port->dev);
-       unsigned int result = 0;
-
-       if (s->use_ms) {
-               u32 sysflg = 0;
-
-               regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg);
-               if (sysflg & SYSFLG1_DCD)
-                       result |= TIOCM_CAR;
-               if (sysflg & SYSFLG1_DSR)
-                       result |= TIOCM_DSR;
-               if (sysflg & SYSFLG1_CTS)
-                       result |= TIOCM_CTS;
-       } else
-               result = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
 
-       return result;
+       return mctrl_gpio_get(s->gpios, &result);
 }
 
 static void uart_clps711x_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
-       /* Do nothing */
+       struct clps711x_port *s = dev_get_drvdata(port->dev);
+
+       mctrl_gpio_set(s->gpios, mctrl);
 }
 
 static void uart_clps711x_break_ctl(struct uart_port *port, int break_state)
@@ -490,15 +481,10 @@ static int uart_clps711x_probe(struct platform_device *pdev)
                s->syscon = syscon_regmap_lookup_by_pdevname(syscon_name);
                if (IS_ERR(s->syscon))
                        return PTR_ERR(s->syscon);
-
-               s->use_ms = !index;
        } else {
                s->syscon = syscon_regmap_lookup_by_phandle(np, "syscon");
                if (IS_ERR(s->syscon))
                        return PTR_ERR(s->syscon);
-
-               if (!index)
-                       s->use_ms = of_property_read_bool(np, "uart-use-ms");
        }
 
        s->port.line            = index;
@@ -513,6 +499,8 @@ static int uart_clps711x_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, s);
 
+       s->gpios = mctrl_gpio_init(&pdev->dev, 0);
+
        ret = uart_add_one_port(&clps711x_uart, &s->port);
        if (ret)
                return ret;