Input: tsc2005 - add DT support

This adds DT support to the tsc2005 touchscreen driver. It also adds
regulator support to the driver if booted via DT.

Reviewed-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

2 files changed, 146 insertions, 20 deletions

diff --git a/Documentation/devicetree/bindings/input/touchscreen/tsc2005.txt b/Documentation/devicetree/bindings/input/touchscreen/tsc2005.txt
new file mode 100644
index 000000000000..4b641c7bf1c2
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/tsc2005.txt
@@ -0,0 +1,42 @@
+* Texas Instruments tsc2005 touchscreen controller
+
+Required properties:
+ - compatible                 : "ti,tsc2005"
+ - reg                        : SPI device address
+ - spi-max-frequency          : Maximal SPI speed
+ - interrupts                 : IRQ specifier
+ - reset-gpios                : GPIO specifier
+ - vio-supply                 : Regulator specifier
+
+Optional properties:
+ - ti,x-plate-ohms            : integer, resistance of the touchscreen's X plates
+                                in ohm (defaults to 280)
+ - ti,esd-recovery-timeout-ms : integer, if the touchscreen does not respond after
+                                the configured time (in milli seconds), the driver
+                                will reset it. This is disabled by default.
+ - properties defined in touchscreen.txt
+
+Example:
+
+&mcspi1 {
+        tsc2005@0 {
+                compatible = "ti,tsc2005";
+                spi-max-frequency = <6000000>;
+                reg = <0>;
+
+                vio-supply = <&vio>;
+
+                reset-gpios = <&gpio4 8 GPIO_ACTIVE_HIGH>; /* 104 */
+                interrupts-extended = <&gpio4 4 IRQ_TYPE_EDGE_RISING>; /* 100 */
+
+                touchscreen-fuzz-x = <4>;
+                touchscreen-fuzz-y = <7>;
+                touchscreen-fuzz-pressure = <2>;
+                touchscreen-max-x = <4096>;
+                touchscreen-max-y = <4096>;
+                touchscreen-max-pressure = <2048>;
+
+                ti,x-plate-ohms = <280>;
+                ti,esd-recovery-timeout-ms = <8000>;
+        };
+}
diff --git a/drivers/input/touchscreen/tsc2005.c b/drivers/input/touchscreen/tsc2005.c
index d981e49368ad..52380b68ebdf 100644
--- a/drivers/input/touchscreen/tsc2005.c
+++ b/drivers/input/touchscreen/tsc2005.c
@@ -25,11 +25,15 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/input.h>
+#include <linux/input/touchscreen.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
 #include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/tsc2005.h>
+#include <linux/regulator/consumer.h>
 
 /*
  * The touchscreen interface operates as follows:
@@ -100,6 +104,11 @@
                                          TSC2005_CFR2_AVG_7)
 
 #define MAX_12BIT                       0xfff
+#define TSC2005_DEF_X_FUZZ              4
+#define TSC2005_DEF_Y_FUZZ              8
+#define TSC2005_DEF_P_FUZZ              2
+#define TSC2005_DEF_RESISTOR            280
+
 #define TSC2005_SPI_MAX_SPEED_HZ        10000000
 #define TSC2005_PENUP_TIME_MS           40
 
@@ -143,6 +152,9 @@ struct tsc2005 {
 
         bool                    pen_down;
 
+        struct regulator        *vio;
+
+        int                     reset_gpio;
         void                    (*set_reset)(bool enable);
 };
 
@@ -337,6 +349,14 @@ static void tsc2005_stop_scan(struct tsc2005 *ts)
         tsc2005_cmd(ts, TSC2005_CMD_STOP);
 }
 
+static void tsc2005_set_reset(struct tsc2005 *ts, bool enable)
+{
+        if (ts->reset_gpio >= 0)
+                gpio_set_value(ts->reset_gpio, enable);
+        else if (ts->set_reset)
+                ts->set_reset(enable);
+}
+
 /* must be called with ts->mutex held */
 static void __tsc2005_disable(struct tsc2005 *ts)
 {
@@ -355,7 +375,7 @@ static void __tsc2005_enable(struct tsc2005 *ts)
 {
         tsc2005_start_scan(ts);
 
-        if (ts->esd_timeout && ts->set_reset) {
+        if (ts->esd_timeout && (ts->set_reset || ts->reset_gpio)) {
                 ts->last_valid_interrupt = jiffies;
                 schedule_delayed_work(&ts->esd_work,
                                 round_jiffies_relative(
@@ -414,9 +434,9 @@ static ssize_t tsc2005_selftest_show(struct device *dev,
         }
 
         /* hardware reset */
-        ts->set_reset(false);
+        tsc2005_set_reset(ts, false);
         usleep_range(100, 500); /* only 10us required */
-        ts->set_reset(true);
+        tsc2005_set_reset(ts, true);
 
         if (!success)
                 goto out;
@@ -459,7 +479,7 @@ static umode_t tsc2005_attr_is_visible(struct kobject *kobj,
         umode_t mode = attr->mode;
 
         if (attr == &dev_attr_selftest.attr) {
-                if (!ts->set_reset)
+                if (!ts->set_reset && !ts->reset_gpio)
                         mode = 0;
         }
 
@@ -509,9 +529,9 @@ static void tsc2005_esd_work(struct work_struct *work)
 
         tsc2005_update_pen_state(ts, 0, 0, 0);
 
-        ts->set_reset(false);
+        tsc2005_set_reset(ts, false);
         usleep_range(100, 500); /* only 10us required */
-        ts->set_reset(true);
+        tsc2005_set_reset(ts, true);
 
         enable_irq(ts->spi->irq);
         tsc2005_start_scan(ts);
@@ -572,29 +592,47 @@ static void tsc2005_setup_spi_xfer(struct tsc2005 *ts)
 static int tsc2005_probe(struct spi_device *spi)
 {
         const struct tsc2005_platform_data *pdata = dev_get_platdata(&spi->dev);
+        struct device_node *np = spi->dev.of_node;
+
         struct tsc2005 *ts;
         struct input_dev *input_dev;
-        unsigned int max_x, max_y, max_p;
-        unsigned int fudge_x, fudge_y, fudge_p;
+        unsigned int max_x = MAX_12BIT;
+        unsigned int max_y = MAX_12BIT;
+        unsigned int max_p = MAX_12BIT;
+        unsigned int fudge_x = TSC2005_DEF_X_FUZZ;
+        unsigned int fudge_y = TSC2005_DEF_Y_FUZZ;
+        unsigned int fudge_p = TSC2005_DEF_P_FUZZ;
+        unsigned int x_plate_ohm = TSC2005_DEF_RESISTOR;
+        unsigned int esd_timeout;
         int error;
 
-        if (!pdata) {
+        if (!np && !pdata) {
                 dev_err(&spi->dev, "no platform data\n");
                 return -ENODEV;
         }
 
-        fudge_x = pdata->ts_x_fudge        ? : 4;
-        fudge_y = pdata->ts_y_fudge        ? : 8;
-        fudge_p = pdata->ts_pressure_fudge ? : 2;
-        max_x   = pdata->ts_x_max          ? : MAX_12BIT;
-        max_y   = pdata->ts_y_max          ? : MAX_12BIT;
-        max_p   = pdata->ts_pressure_max   ? : MAX_12BIT;
-
         if (spi->irq <= 0) {
                 dev_err(&spi->dev, "no irq\n");
                 return -ENODEV;
         }
 
+        if (pdata) {
+                fudge_x = pdata->ts_x_fudge;
+                fudge_y = pdata->ts_y_fudge;
+                fudge_p = pdata->ts_pressure_fudge;
+                max_x   = pdata->ts_x_max;
+                max_y   = pdata->ts_y_max;
+                max_p   = pdata->ts_pressure_max;
+                x_plate_ohm = pdata->ts_x_plate_ohm;
+                esd_timeout = pdata->esd_timeout_ms;
+        } else {
+                x_plate_ohm = TSC2005_DEF_RESISTOR;
+                of_property_read_u32(np, "ti,x-plate-ohms", &x_plate_ohm);
+                esd_timeout = 0;
+                of_property_read_u32(np, "ti,esd-recovery-timeout-ms",
+                                                                &esd_timeout);
+        }
+
         spi->mode = SPI_MODE_0;
         spi->bits_per_word = 8;
         if (!spi->max_speed_hz)
@@ -615,9 +653,37 @@ static int tsc2005_probe(struct spi_device *spi)
         ts->spi = spi;
         ts->idev = input_dev;
 
-        ts->x_plate_ohm = pdata->ts_x_plate_ohm ? : 280;
-        ts->esd_timeout = pdata->esd_timeout_ms;
-        ts->set_reset   = pdata->set_reset;
+        ts->x_plate_ohm = x_plate_ohm;
+        ts->esd_timeout = esd_timeout;
+
+        if (np) {
+                ts->reset_gpio = of_get_named_gpio(np, "reset-gpios", 0);
+                if (ts->reset_gpio == -EPROBE_DEFER)
+                        return ts->reset_gpio;
+                if (ts->reset_gpio < 0) {
+                        dev_err(&spi->dev, "error acquiring reset gpio: %d\n",
+                                ts->reset_gpio);
+                        return ts->reset_gpio;
+                }
+
+                error = devm_gpio_request_one(&spi->dev, ts->reset_gpio, 0,
+                                              "reset-gpios");
+                if (error) {
+                        dev_err(&spi->dev, "error requesting reset gpio: %d\n",
+                                error);
+                        return error;
+                }
+
+                ts->vio = devm_regulator_get(&spi->dev, "vio");
+                if (IS_ERR(ts->vio)) {
+                        error = PTR_ERR(ts->vio);
+                        dev_err(&spi->dev, "vio regulator missing (%d)", error);
+                        return error;
+                }
+        } else {
+                ts->reset_gpio = -1;
+                ts->set_reset = pdata->set_reset;
+        }
 
         mutex_init(&ts->mutex);
 
@@ -642,6 +708,9 @@ static int tsc2005_probe(struct spi_device *spi)
         input_set_abs_params(input_dev, ABS_Y, 0, max_y, fudge_y, 0);
         input_set_abs_params(input_dev, ABS_PRESSURE, 0, max_p, fudge_p, 0);
 
+        if (np)
+                touchscreen_parse_of_params(input_dev);
+
         input_dev->open = tsc2005_open;
         input_dev->close = tsc2005_close;
 
@@ -659,12 +728,19 @@ static int tsc2005_probe(struct spi_device *spi)
                 return error;
         }
 
+        /* enable regulator for DT */
+        if (ts->vio) {
+                error = regulator_enable(ts->vio);
+                if (error)
+                        return error;
+        }
+
         spi_set_drvdata(spi, ts);
         error = sysfs_create_group(&spi->dev.kobj, &tsc2005_attr_group);
         if (error) {
                 dev_err(&spi->dev,
                         "Failed to create sysfs attributes, err: %d\n", error);
-                return error;
+                goto disable_regulator;
         }
 
         error = input_register_device(ts->idev);
@@ -679,13 +755,21 @@ static int tsc2005_probe(struct spi_device *spi)
 
 err_remove_sysfs:
         sysfs_remove_group(&spi->dev.kobj, &tsc2005_attr_group);
+disable_regulator:
+        if (ts->vio)
+                regulator_disable(ts->vio);
         return error;
 }
 
 static int tsc2005_remove(struct spi_device *spi)
 {
+        struct tsc2005 *ts = spi_get_drvdata(spi);
+
         sysfs_remove_group(&spi->dev.kobj, &tsc2005_attr_group);
 
+        if (ts->vio)
+                regulator_disable(ts->vio);
+
         return 0;
 }