15 files changed, 947 insertions, 15 deletions

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index 9d35499faca4..08d496411f75 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -290,19 +290,14 @@ static int evdev_flush(struct file *file, fl_owner_t id)
 {
 	struct evdev_client *client = file->private_data;
 	struct evdev *evdev = client->evdev;
-	int retval;
 
-	retval = mutex_lock_interruptible(&evdev->mutex);
-	if (retval)
-		return retval;
+	mutex_lock(&evdev->mutex);
 
-	if (!evdev->exist || client->revoked)
-		retval = -ENODEV;
-	else
-		retval = input_flush_device(&evdev->handle, file);
+	if (evdev->exist && !client->revoked)
+		input_flush_device(&evdev->handle, file);
 
 	mutex_unlock(&evdev->mutex);
-	return retval;
+	return 0;
 }
 
 static void evdev_free(struct device *dev)
diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
index d2ea863d6a45..2165f3dd328b 100644
--- a/drivers/input/keyboard/imx_keypad.c
+++ b/drivers/input/keyboard/imx_keypad.c
@@ -5,8 +5,6 @@
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
- *
- * <<Power management needs to be implemented>>.
  */
 
 #include <linux/clk.h>
diff --git a/drivers/input/misc/ab8500-ponkey.c b/drivers/input/misc/ab8500-ponkey.c
index 1f7e15ca5fbe..4f5ef5bb535b 100644
--- a/drivers/input/misc/ab8500-ponkey.c
+++ b/drivers/input/misc/ab8500-ponkey.c
@@ -118,6 +118,7 @@ static const struct of_device_id ab8500_ponkey_match[] = {
 	{ .compatible = "stericsson,ab8500-ponkey", },
 	{}
 };
+MODULE_DEVICE_TABLE(of, ab8500_ponkey_match);
 #endif
 
 static struct platform_driver ab8500_ponkey_driver = {
diff --git a/drivers/input/misc/pwm-beeper.c b/drivers/input/misc/pwm-beeper.c
index e82edf810d1f..f2261ab54701 100644
--- a/drivers/input/misc/pwm-beeper.c
+++ b/drivers/input/misc/pwm-beeper.c
@@ -173,6 +173,7 @@ static const struct of_device_id pwm_beeper_match[] = {
 	{ .compatible = "pwm-beeper", },
 	{ },
 };
+MODULE_DEVICE_TABLE(of, pwm_beeper_match);
 #endif
 
 static struct platform_driver pwm_beeper_driver = {
diff --git a/drivers/input/misc/regulator-haptic.c b/drivers/input/misc/regulator-haptic.c
index 6bf3f1082f71..a804705eb04a 100644
--- a/drivers/input/misc/regulator-haptic.c
+++ b/drivers/input/misc/regulator-haptic.c
@@ -249,6 +249,7 @@ static const struct of_device_id regulator_haptic_dt_match[] = {
 	{ .compatible = "regulator-haptic" },
 	{ /* sentinel */ },
 };
+MODULE_DEVICE_TABLE(of, regulator_haptic_dt_match);
 
 static struct platform_driver regulator_haptic_driver = {
 	.probe		= regulator_haptic_probe,
diff --git a/drivers/input/misc/sparcspkr.c b/drivers/input/misc/sparcspkr.c
index 54116e544c96..6f997aa49183 100644
--- a/drivers/input/misc/sparcspkr.c
+++ b/drivers/input/misc/sparcspkr.c
@@ -253,6 +253,7 @@ static const struct of_device_id bbc_beep_match[] = {
 	},
 	{},
 };
+MODULE_DEVICE_TABLE(of, bbc_beep_match);
 
 static struct platform_driver bbc_beep_driver = {
 	.driver = {
@@ -332,6 +333,7 @@ static const struct of_device_id grover_beep_match[] = {
 	},
 	{},
 };
+MODULE_DEVICE_TABLE(of, grover_beep_match);
 
 static struct platform_driver grover_beep_driver = {
 	.driver = {
diff --git a/drivers/input/mouse/elan_i2c_core.c b/drivers/input/mouse/elan_i2c_core.c
index e2b7420eed97..fa945304b9a5 100644
--- a/drivers/input/mouse/elan_i2c_core.c
+++ b/drivers/input/mouse/elan_i2c_core.c
@@ -1170,6 +1170,7 @@ static const struct acpi_device_id elan_acpi_id[] = {
 	{ "ELAN0000", 0 },
 	{ "ELAN0100", 0 },
 	{ "ELAN0600", 0 },
+	{ "ELAN1000", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c
index c9c98f0ab284..db91de539ee3 100644
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -877,7 +877,7 @@ static int __init i8042_check_aux(void)
 static int i8042_controller_check(void)
 {
 	if (i8042_flush()) {
-		pr_err("No controller found\n");
+		pr_info("No controller found\n");
 		return -ENODEV;
 	}
 
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 059edeb7f04a..600dcceff542 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -479,6 +479,18 @@ config TOUCHSCREEN_MTOUCH
 	  To compile this driver as a module, choose M here: the
 	  module will be called mtouch.
 
+config TOUCHSCREEN_IMX6UL_TSC
+	tristate "Freescale i.MX6UL touchscreen controller"
+	depends on (OF && GPIOLIB) || COMPILE_TEST
+	help
+	  Say Y here if you have a Freescale i.MX6UL, and want to
+	  use the internal touchscreen controller.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called imx6ul_tsc.
+
 config TOUCHSCREEN_INEXIO
 	tristate "iNexio serial touchscreens"
 	select SERIO
@@ -1040,4 +1052,16 @@ config TOUCHSCREEN_ZFORCE
 	  To compile this driver as a module, choose M here: the
 	  module will be called zforce_ts.
 
+config TOUCHSCREEN_COLIBRI_VF50
+	tristate "Toradex Colibri on board touchscreen driver"
+	depends on GPIOLIB && IIO && VF610_ADC
+	help
+	  Say Y here if you have a Colibri VF50 and plan to use
+	  the on-board provided 4-wire touchscreen driver.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called colibri_vf50_ts.
+
 endif
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index c85aae23e7f8..1b79cc09744a 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -38,6 +38,7 @@ obj-$(CONFIG_TOUCHSCREEN_EGALAX)	+= egalax_ts.o
 obj-$(CONFIG_TOUCHSCREEN_FUJITSU)	+= fujitsu_ts.o
 obj-$(CONFIG_TOUCHSCREEN_GOODIX)	+= goodix.o
 obj-$(CONFIG_TOUCHSCREEN_ILI210X)	+= ili210x.o
+obj-$(CONFIG_TOUCHSCREEN_IMX6UL_TSC)	+= imx6ul_tsc.o
 obj-$(CONFIG_TOUCHSCREEN_INEXIO)	+= inexio.o
 obj-$(CONFIG_TOUCHSCREEN_INTEL_MID)	+= intel-mid-touch.o
 obj-$(CONFIG_TOUCHSCREEN_IPROC)		+= bcm_iproc_tsc.o
@@ -85,3 +86,4 @@ obj-$(CONFIG_TOUCHSCREEN_W90X900)	+= w90p910_ts.o
 obj-$(CONFIG_TOUCHSCREEN_SX8654)	+= sx8654.o
 obj-$(CONFIG_TOUCHSCREEN_TPS6507X)	+= tps6507x-ts.o
 obj-$(CONFIG_TOUCHSCREEN_ZFORCE)	+= zforce_ts.o
+obj-$(CONFIG_TOUCHSCREEN_COLIBRI_VF50)	+= colibri-vf50-ts.o
diff --git a/drivers/input/touchscreen/colibri-vf50-ts.c b/drivers/input/touchscreen/colibri-vf50-ts.c
new file mode 100644
index 000000000000..5d4903a402cc
--- /dev/null
+++ b/drivers/input/touchscreen/colibri-vf50-ts.c
@@ -0,0 +1,386 @@
+/*
+ * Toradex Colibri VF50 Touchscreen driver
+ *
+ * Copyright 2015 Toradex AG
+ *
+ * Originally authored by Stefan Agner for 3.0 kernel
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/consumer.h>
+#include <linux/iio/types.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define DRIVER_NAME			"colibri-vf50-ts"
+#define DRV_VERSION			"1.0"
+
+#define VF_ADC_MAX			((1 << 12) - 1)
+
+#define COLI_TOUCH_MIN_DELAY_US		1000
+#define COLI_TOUCH_MAX_DELAY_US		2000
+#define COLI_PULLUP_MIN_DELAY_US	10000
+#define COLI_PULLUP_MAX_DELAY_US	11000
+#define COLI_TOUCH_NO_OF_AVGS		5
+#define COLI_TOUCH_REQ_ADC_CHAN		4
+
+struct vf50_touch_device {
+	struct platform_device *pdev;
+	struct input_dev *ts_input;
+	struct iio_channel *channels;
+	struct gpio_desc *gpio_xp;
+	struct gpio_desc *gpio_xm;
+	struct gpio_desc *gpio_yp;
+	struct gpio_desc *gpio_ym;
+	int pen_irq;
+	int min_pressure;
+	bool stop_touchscreen;
+};
+
+/*
+ * Enables given plates and measures touch parameters using ADC
+ */
+static int adc_ts_measure(struct iio_channel *channel,
+			  struct gpio_desc *plate_p, struct gpio_desc *plate_m)
+{
+	int i, value = 0, val = 0;
+	int error;
+
+	gpiod_set_value(plate_p, 1);
+	gpiod_set_value(plate_m, 1);
+
+	usleep_range(COLI_TOUCH_MIN_DELAY_US, COLI_TOUCH_MAX_DELAY_US);
+
+	for (i = 0; i < COLI_TOUCH_NO_OF_AVGS; i++) {
+		error = iio_read_channel_raw(channel, &val);
+		if (error < 0) {
+			value = error;
+			goto error_iio_read;
+		}
+
+		value += val;
+	}
+
+	value /= COLI_TOUCH_NO_OF_AVGS;
+
+error_iio_read:
+	gpiod_set_value(plate_p, 0);
+	gpiod_set_value(plate_m, 0);
+
+	return value;
+}
+
+/*
+ * Enable touch detection using falling edge detection on XM
+ */
+static void vf50_ts_enable_touch_detection(struct vf50_touch_device *vf50_ts)
+{
+	/* Enable plate YM (needs to be strong GND, high active) */
+	gpiod_set_value(vf50_ts->gpio_ym, 1);
+
+	/*
+	 * Let the platform mux to idle state in order to enable
+	 * Pull-Up on GPIO
+	 */
+	pinctrl_pm_select_idle_state(&vf50_ts->pdev->dev);
+
+	/* Wait for the pull-up to be stable on high */
+	usleep_range(COLI_PULLUP_MIN_DELAY_US, COLI_PULLUP_MAX_DELAY_US);
+}
+
+/*
+ * ADC touch screen sampling bottom half irq handler
+ */
+static irqreturn_t vf50_ts_irq_bh(int irq, void *private)
+{
+	struct vf50_touch_device *vf50_ts = private;
+	struct device *dev = &vf50_ts->pdev->dev;
+	int val_x, val_y, val_z1, val_z2, val_p = 0;
+	bool discard_val_on_start = true;
+
+	/* Disable the touch detection plates */
+	gpiod_set_value(vf50_ts->gpio_ym, 0);
+
+	/* Let the platform mux to default state in order to mux as ADC */
+	pinctrl_pm_select_default_state(dev);
+
+	while (!vf50_ts->stop_touchscreen) {
+		/* X-Direction */
+		val_x = adc_ts_measure(&vf50_ts->channels[0],
+				vf50_ts->gpio_xp, vf50_ts->gpio_xm);
+		if (val_x < 0)
+			break;
+
+		/* Y-Direction */
+		val_y = adc_ts_measure(&vf50_ts->channels[1],
+				vf50_ts->gpio_yp, vf50_ts->gpio_ym);
+		if (val_y < 0)
+			break;
+
+		/*
+		 * Touch pressure
+		 * Measure on XP/YM
+		 */
+		val_z1 = adc_ts_measure(&vf50_ts->channels[2],
+				vf50_ts->gpio_yp, vf50_ts->gpio_xm);
+		if (val_z1 < 0)
+			break;
+		val_z2 = adc_ts_measure(&vf50_ts->channels[3],
+				vf50_ts->gpio_yp, vf50_ts->gpio_xm);
+		if (val_z2 < 0)
+			break;
+
+		/* Validate signal (avoid calculation using noise) */
+		if (val_z1 > 64 && val_x > 64) {
+			/*
+			 * Calculate resistance between the plates
+			 * lower resistance means higher pressure
+			 */
+			int r_x = (1000 * val_x) / VF_ADC_MAX;
+
+			val_p = (r_x * val_z2) / val_z1 - r_x;
+
+		} else {
+			val_p = 2000;
+		}
+
+		val_p = 2000 - val_p;
+		dev_dbg(dev,
+			"Measured values: x: %d, y: %d, z1: %d, z2: %d, p: %d\n",
+			val_x, val_y, val_z1, val_z2, val_p);
+
+		/*
+		 * If touch pressure is too low, stop measuring and reenable
+		 * touch detection
+		 */
+		if (val_p < vf50_ts->min_pressure || val_p > 2000)
+			break;
+
+		/*
+		 * The pressure may not be enough for the first x and the
+		 * second y measurement, but, the pressure is ok when the
+		 * driver is doing the third and fourth measurement. To
+		 * take care of this, we drop the first measurement always.
+		 */
+		if (discard_val_on_start) {
+			discard_val_on_start = false;
+		} else {
+			/*
+			 * Report touch position and sleep for
+			 * the next measurement.
+			 */
+			input_report_abs(vf50_ts->ts_input,
+					ABS_X, VF_ADC_MAX - val_x);
+			input_report_abs(vf50_ts->ts_input,
+					ABS_Y, VF_ADC_MAX - val_y);
+			input_report_abs(vf50_ts->ts_input,
+					ABS_PRESSURE, val_p);
+			input_report_key(vf50_ts->ts_input, BTN_TOUCH, 1);
+			input_sync(vf50_ts->ts_input);
+		}
+
+		usleep_range(COLI_PULLUP_MIN_DELAY_US,
+			     COLI_PULLUP_MAX_DELAY_US);
+	}
+
+	/* Report no more touch, re-enable touch detection */
+	input_report_abs(vf50_ts->ts_input, ABS_PRESSURE, 0);
+	input_report_key(vf50_ts->ts_input, BTN_TOUCH, 0);
+	input_sync(vf50_ts->ts_input);
+
+	vf50_ts_enable_touch_detection(vf50_ts);
+
+	return IRQ_HANDLED;
+}
+
+static int vf50_ts_open(struct input_dev *dev_input)
+{
+	struct vf50_touch_device *touchdev = input_get_drvdata(dev_input);
+	struct device *dev = &touchdev->pdev->dev;
+
+	dev_dbg(dev, "Input device %s opened, starting touch detection\n",
+		dev_input->name);
+
+	touchdev->stop_touchscreen = false;
+
+	/* Mux detection before request IRQ, wait for pull-up to settle */
+	vf50_ts_enable_touch_detection(touchdev);
+
+	return 0;
+}
+
+static void vf50_ts_close(struct input_dev *dev_input)
+{
+	struct vf50_touch_device *touchdev = input_get_drvdata(dev_input);
+	struct device *dev = &touchdev->pdev->dev;
+
+	touchdev->stop_touchscreen = true;
+
+	/* Make sure IRQ is not running past close */
+	mb();
+	synchronize_irq(touchdev->pen_irq);
+
+	gpiod_set_value(touchdev->gpio_ym, 0);
+	pinctrl_pm_select_default_state(dev);
+
+	dev_dbg(dev, "Input device %s closed, disable touch detection\n",
+		dev_input->name);
+}
+
+static int vf50_ts_get_gpiod(struct device *dev, struct gpio_desc **gpio_d,
+			     const char *con_id, enum gpiod_flags flags)
+{
+	int error;
+
+	*gpio_d = devm_gpiod_get(dev, con_id, flags);
+	if (IS_ERR(*gpio_d)) {
+		error = PTR_ERR(*gpio_d);
+		dev_err(dev, "Could not get gpio_%s %d\n", con_id, error);
+		return error;
+	}
+
+	return 0;
+}
+
+static void vf50_ts_channel_release(void *data)
+{
+	struct iio_channel *channels = data;
+
+	iio_channel_release_all(channels);
+}
+
+static int vf50_ts_probe(struct platform_device *pdev)
+{
+	struct input_dev *input;
+	struct iio_channel *channels;
+	struct device *dev = &pdev->dev;
+	struct vf50_touch_device *touchdev;
+	int num_adc_channels;
+	int error;
+
+	channels = iio_channel_get_all(dev);
+	if (IS_ERR(channels))
+		return PTR_ERR(channels);
+
+	error = devm_add_action(dev, vf50_ts_channel_release, channels);
+	if (error) {
+		iio_channel_release_all(channels);
+		dev_err(dev, "Failed to register iio channel release action");
+		return error;
+	}
+
+	num_adc_channels = 0;
+	while (channels[num_adc_channels].indio_dev)
+		num_adc_channels++;
+
+	if (num_adc_channels != COLI_TOUCH_REQ_ADC_CHAN) {
+		dev_err(dev, "Inadequate ADC channels specified\n");
+		return -EINVAL;
+	}
+
+	touchdev = devm_kzalloc(dev, sizeof(*touchdev), GFP_KERNEL);
+	if (!touchdev)
+		return -ENOMEM;
+
+	touchdev->pdev = pdev;
+	touchdev->channels = channels;
+
+	error = of_property_read_u32(dev->of_node, "vf50-ts-min-pressure",
+				 &touchdev->min_pressure);
+	if (error)
+		return error;
+
+	input = devm_input_allocate_device(dev);
+	if (!input) {
+		dev_err(dev, "Failed to allocate TS input device\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, touchdev);
+
+	input->name = DRIVER_NAME;
+	input->id.bustype = BUS_HOST;
+	input->dev.parent = dev;
+	input->open = vf50_ts_open;
+	input->close = vf50_ts_close;
+
+	input_set_capability(input, EV_KEY, BTN_TOUCH);
+	input_set_abs_params(input, ABS_X, 0, VF_ADC_MAX, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, VF_ADC_MAX, 0, 0);
+	input_set_abs_params(input, ABS_PRESSURE, 0, VF_ADC_MAX, 0, 0);
+
+	touchdev->ts_input = input;
+	input_set_drvdata(input, touchdev);
+
+	error = input_register_device(input);
+	if (error) {
+		dev_err(dev, "Failed to register input device\n");
+		return error;
+	}
+
+	error = vf50_ts_get_gpiod(dev, &touchdev->gpio_xp, "xp", GPIOD_OUT_LOW);
+	if (error)
+		return error;
+
+	error = vf50_ts_get_gpiod(dev, &touchdev->gpio_xm,
+				"xm", GPIOD_OUT_LOW);
+	if (error)
+		return error;
+
+	error = vf50_ts_get_gpiod(dev, &touchdev->gpio_yp, "yp", GPIOD_OUT_LOW);
+	if (error)
+		return error;
+
+	error = vf50_ts_get_gpiod(dev, &touchdev->gpio_ym, "ym", GPIOD_OUT_LOW);
+	if (error)
+		return error;
+
+	touchdev->pen_irq = platform_get_irq(pdev, 0);
+	if (touchdev->pen_irq < 0)
+		return touchdev->pen_irq;
+
+	error = devm_request_threaded_irq(dev, touchdev->pen_irq,
+					  NULL, vf50_ts_irq_bh, IRQF_ONESHOT,
+					  "vf50 touch", touchdev);
+	if (error) {
+		dev_err(dev, "Failed to request IRQ %d: %d\n",
+			touchdev->pen_irq, error);
+		return error;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id vf50_touch_of_match[] = {
+	{ .compatible = "toradex,vf50-touchscreen", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, vf50_touch_of_match);
+
+static struct platform_driver vf50_touch_driver = {
+	.driver = {
+		.name = "toradex,vf50_touchctrl",
+		.of_match_table = vf50_touch_of_match,
+	},
+	.probe = vf50_ts_probe,
+};
+module_platform_driver(vf50_touch_driver);
+
+MODULE_AUTHOR("Sanchayan Maity");
+MODULE_DESCRIPTION("Colibri VF50 Touchscreen driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
diff --git a/drivers/input/touchscreen/cyttsp4_i2c.c b/drivers/input/touchscreen/cyttsp4_i2c.c
index 9a323dd915de..a9f95c7d3c00 100644
--- a/drivers/input/touchscreen/cyttsp4_i2c.c
+++ b/drivers/input/touchscreen/cyttsp4_i2c.c
@@ -86,4 +86,3 @@ module_i2c_driver(cyttsp4_i2c_driver);
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
 MODULE_AUTHOR("Cypress");
-MODULE_ALIAS("i2c:cyttsp4");
diff --git a/drivers/input/touchscreen/cyttsp_i2c.c b/drivers/input/touchscreen/cyttsp_i2c.c
index 519e2de2f8df..eee51b3f2e3f 100644
--- a/drivers/input/touchscreen/cyttsp_i2c.c
+++ b/drivers/input/touchscreen/cyttsp_i2c.c
@@ -86,4 +86,3 @@ module_i2c_driver(cyttsp_i2c_driver);
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
 MODULE_AUTHOR("Cypress");
-MODULE_ALIAS("i2c:cyttsp");
diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c
index ddac134b25b1..17cc20ef4923 100644
--- a/drivers/input/touchscreen/elants_i2c.c
+++ b/drivers/input/touchscreen/elants_i2c.c
@@ -102,7 +102,7 @@
 #define ELAN_FW_PAGESIZE	132
 
 /* calibration timeout definition */
-#define ELAN_CALI_TIMEOUT_MSEC	10000
+#define ELAN_CALI_TIMEOUT_MSEC	12000
 
 #define ELAN_POWERON_DELAY_USEC	500
 #define ELAN_RESET_DELAY_MSEC	20
diff --git a/drivers/input/touchscreen/imx6ul_tsc.c b/drivers/input/touchscreen/imx6ul_tsc.c
new file mode 100644
index 000000000000..ff0b75813daa
--- /dev/null
+++ b/drivers/input/touchscreen/imx6ul_tsc.c
@@ -0,0 +1,523 @@
+/*
+ * Freescale i.MX6UL touchscreen controller driver
+ *
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+/* ADC configuration registers field define */
+#define ADC_AIEN		(0x1 << 7)
+#define ADC_CONV_DISABLE	0x1F
+#define ADC_CAL			(0x1 << 7)
+#define ADC_CALF		0x2
+#define ADC_12BIT_MODE		(0x2 << 2)
+#define ADC_IPG_CLK		0x00
+#define ADC_CLK_DIV_8		(0x03 << 5)
+#define ADC_SHORT_SAMPLE_MODE	(0x0 << 4)
+#define ADC_HARDWARE_TRIGGER	(0x1 << 13)
+#define SELECT_CHANNEL_4	0x04
+#define SELECT_CHANNEL_1	0x01
+#define DISABLE_CONVERSION_INT	(0x0 << 7)
+
+/* ADC registers */
+#define REG_ADC_HC0		0x00
+#define REG_ADC_HC1		0x04
+#define REG_ADC_HC2		0x08
+#define REG_ADC_HC3		0x0C
+#define REG_ADC_HC4		0x10
+#define REG_ADC_HS		0x14
+#define REG_ADC_R0		0x18
+#define REG_ADC_CFG		0x2C
+#define REG_ADC_GC		0x30
+#define REG_ADC_GS		0x34
+
+#define ADC_TIMEOUT		msecs_to_jiffies(100)
+
+/* TSC registers */
+#define REG_TSC_BASIC_SETING	0x00
+#define REG_TSC_PRE_CHARGE_TIME	0x10
+#define REG_TSC_FLOW_CONTROL	0x20
+#define REG_TSC_MEASURE_VALUE	0x30
+#define REG_TSC_INT_EN		0x40
+#define REG_TSC_INT_SIG_EN	0x50
+#define REG_TSC_INT_STATUS	0x60
+#define REG_TSC_DEBUG_MODE	0x70
+#define REG_TSC_DEBUG_MODE2	0x80
+
+/* TSC configuration registers field define */
+#define DETECT_4_WIRE_MODE	(0x0 << 4)
+#define AUTO_MEASURE		0x1
+#define MEASURE_SIGNAL		0x1
+#define DETECT_SIGNAL		(0x1 << 4)
+#define VALID_SIGNAL		(0x1 << 8)
+#define MEASURE_INT_EN		0x1
+#define MEASURE_SIG_EN		0x1
+#define VALID_SIG_EN		(0x1 << 8)
+#define DE_GLITCH_2		(0x2 << 29)
+#define START_SENSE		(0x1 << 12)
+#define TSC_DISABLE		(0x1 << 16)
+#define DETECT_MODE		0x2
+
+struct imx6ul_tsc {
+	struct device *dev;
+	struct input_dev *input;
+	void __iomem *tsc_regs;
+	void __iomem *adc_regs;
+	struct clk *tsc_clk;
+	struct clk *adc_clk;
+	struct gpio_desc *xnur_gpio;
+
+	int measure_delay_time;
+	int pre_charge_time;
+
+	struct completion completion;
+};
+
+/*
+ * TSC module need ADC to get the measure value. So
+ * before config TSC, we should initialize ADC module.
+ */
+static void imx6ul_adc_init(struct imx6ul_tsc *tsc)
+{
+	int adc_hc = 0;
+	int adc_gc;
+	int adc_gs;
+	int adc_cfg;
+	int timeout;
+
+	reinit_completion(&tsc->completion);
+
+	adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
+	adc_cfg |= ADC_12BIT_MODE | ADC_IPG_CLK;
+	adc_cfg |= ADC_CLK_DIV_8 | ADC_SHORT_SAMPLE_MODE;
+	adc_cfg &= ~ADC_HARDWARE_TRIGGER;
+	writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
+
+	/* enable calibration interrupt */
+	adc_hc |= ADC_AIEN;
+	adc_hc |= ADC_CONV_DISABLE;
+	writel(adc_hc, tsc->adc_regs + REG_ADC_HC0);
+
+	/* start ADC calibration */
+	adc_gc = readl(tsc->adc_regs + REG_ADC_GC);
+	adc_gc |= ADC_CAL;
+	writel(adc_gc, tsc->adc_regs + REG_ADC_GC);
+
+	timeout = wait_for_completion_timeout
+			(&tsc->completion, ADC_TIMEOUT);
+	if (timeout == 0)
+		dev_err(tsc->dev, "Timeout for adc calibration\n");
+
+	adc_gs = readl(tsc->adc_regs + REG_ADC_GS);
+	if (adc_gs & ADC_CALF)
+		dev_err(tsc->dev, "ADC calibration failed\n");
+
+	/* TSC need the ADC work in hardware trigger */
+	adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
+	adc_cfg |= ADC_HARDWARE_TRIGGER;
+	writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
+}
+
+/*
+ * This is a TSC workaround. Currently TSC misconnect two
+ * ADC channels, this function remap channel configure for
+ * hardware trigger.
+ */
+static void imx6ul_tsc_channel_config(struct imx6ul_tsc *tsc)
+{
+	int adc_hc0, adc_hc1, adc_hc2, adc_hc3, adc_hc4;
+
+	adc_hc0 = DISABLE_CONVERSION_INT;
+	writel(adc_hc0, tsc->adc_regs + REG_ADC_HC0);
+
+	adc_hc1 = DISABLE_CONVERSION_INT | SELECT_CHANNEL_4;
+	writel(adc_hc1, tsc->adc_regs + REG_ADC_HC1);
+
+	adc_hc2 = DISABLE_CONVERSION_INT;
+	writel(adc_hc2, tsc->adc_regs + REG_ADC_HC2);
+
+	adc_hc3 = DISABLE_CONVERSION_INT | SELECT_CHANNEL_1;
+	writel(adc_hc3, tsc->adc_regs + REG_ADC_HC3);
+
+	adc_hc4 = DISABLE_CONVERSION_INT;
+	writel(adc_hc4, tsc->adc_regs + REG_ADC_HC4);
+}
+
+/*
+ * TSC setting, confige the pre-charge time and measure delay time.
+ * different touch screen may need different pre-charge time and
+ * measure delay time.
+ */
+static void imx6ul_tsc_set(struct imx6ul_tsc *tsc)
+{
+	int basic_setting = 0;
+	int start;
+
+	basic_setting |= tsc->measure_delay_time << 8;
+	basic_setting |= DETECT_4_WIRE_MODE | AUTO_MEASURE;
+	writel(basic_setting, tsc->tsc_regs + REG_TSC_BASIC_SETING);
+
+	writel(DE_GLITCH_2, tsc->tsc_regs + REG_TSC_DEBUG_MODE2);
+
+	writel(tsc->pre_charge_time, tsc->tsc_regs + REG_TSC_PRE_CHARGE_TIME);
+	writel(MEASURE_INT_EN, tsc->tsc_regs + REG_TSC_INT_EN);
+	writel(MEASURE_SIG_EN | VALID_SIG_EN,
+		tsc->tsc_regs + REG_TSC_INT_SIG_EN);
+
+	/* start sense detection */
+	start = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+	start |= START_SENSE;
+	start &= ~TSC_DISABLE;
+	writel(start, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+}
+
+static void imx6ul_tsc_init(struct imx6ul_tsc *tsc)
+{
+	imx6ul_adc_init(tsc);
+	imx6ul_tsc_channel_config(tsc);
+	imx6ul_tsc_set(tsc);
+}
+
+static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
+{
+	int tsc_flow;
+	int adc_cfg;
+
+	/* TSC controller enters to idle status */
+	tsc_flow = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+	tsc_flow |= TSC_DISABLE;
+	writel(tsc_flow, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+
+	/* ADC controller enters to stop mode */
+	adc_cfg = readl(tsc->adc_regs + REG_ADC_HC0);
+	adc_cfg |= ADC_CONV_DISABLE;
+	writel(adc_cfg, tsc->adc_regs + REG_ADC_HC0);
+}
+
+/* Delay some time (max 2ms), wait the pre-charge done. */
+static bool tsc_wait_detect_mode(struct imx6ul_tsc *tsc)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(2);
+	int state_machine;
+	int debug_mode2;
+
+	do {
+		if (time_after(jiffies, timeout))
+			return false;
+
+		usleep_range(200, 400);
+		debug_mode2 = readl(tsc->tsc_regs + REG_TSC_DEBUG_MODE2);
+		state_machine = (debug_mode2 >> 20) & 0x7;
+	} while (state_machine != DETECT_MODE);
+
+	usleep_range(200, 400);
+	return true;
+}
+
+static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
+{
+	struct imx6ul_tsc *tsc = dev_id;
+	int status;
+	int value;
+	int x, y;
+	int start;
+
+	status = readl(tsc->tsc_regs + REG_TSC_INT_STATUS);
+
+	/* write 1 to clear the bit measure-signal */
+	writel(MEASURE_SIGNAL | DETECT_SIGNAL,
+		tsc->tsc_regs + REG_TSC_INT_STATUS);
+
+	/* It's a HW self-clean bit. Set this bit and start sense detection */
+	start = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+	start |= START_SENSE;
+	writel(start, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+
+	if (status & MEASURE_SIGNAL) {
+		value = readl(tsc->tsc_regs + REG_TSC_MEASURE_VALUE);
+		x = (value >> 16) & 0x0fff;
+		y = value & 0x0fff;
+
+		/*
+		 * In detect mode, we can get the xnur gpio value,
+		 * otherwise assume contact is stiull active.
+		 */
+		if (!tsc_wait_detect_mode(tsc) ||
+		    gpiod_get_value_cansleep(tsc->xnur_gpio)) {
+			input_report_key(tsc->input, BTN_TOUCH, 1);
+			input_report_abs(tsc->input, ABS_X, x);
+			input_report_abs(tsc->input, ABS_Y, y);
+		} else {
+			input_report_key(tsc->input, BTN_TOUCH, 0);
+		}
+
+		input_sync(tsc->input);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t adc_irq_fn(int irq, void *dev_id)
+{
+	struct imx6ul_tsc *tsc = dev_id;
+	int coco;
+	int value;
+
+	coco = readl(tsc->adc_regs + REG_ADC_HS);
+	if (coco & 0x01) {
+		value = readl(tsc->adc_regs + REG_ADC_R0);
+		complete(&tsc->completion);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int imx6ul_tsc_open(struct input_dev *input_dev)
+{
+	struct imx6ul_tsc *tsc = input_get_drvdata(input_dev);
+	int err;
+
+	err = clk_prepare_enable(tsc->adc_clk);
+	if (err) {
+		dev_err(tsc->dev,
+			"Could not prepare or enable the adc clock: %d\n",
+			err);
+		return err;
+	}
+
+	err = clk_prepare_enable(tsc->tsc_clk);
+	if (err) {
+		dev_err(tsc->dev,
+			"Could not prepare or enable the tsc clock: %d\n",
+			err);
+		clk_disable_unprepare(tsc->adc_clk);
+		return err;
+	}
+
+	imx6ul_tsc_init(tsc);
+
+	return 0;
+}
+
+static void imx6ul_tsc_close(struct input_dev *input_dev)
+{
+	struct imx6ul_tsc *tsc = input_get_drvdata(input_dev);
+
+	imx6ul_tsc_disable(tsc);
+
+	clk_disable_unprepare(tsc->tsc_clk);
+	clk_disable_unprepare(tsc->adc_clk);
+}
+
+static int imx6ul_tsc_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct imx6ul_tsc *tsc;
+	struct input_dev *input_dev;
+	struct resource *tsc_mem;
+	struct resource *adc_mem;
+	int err;
+	int tsc_irq;
+	int adc_irq;
+
+	tsc = devm_kzalloc(&pdev->dev, sizeof(struct imx6ul_tsc), GFP_KERNEL);
+	if (!tsc)
+		return -ENOMEM;
+
+	input_dev = devm_input_allocate_device(&pdev->dev);
+	if (!input_dev)
+		return -ENOMEM;
+
+	input_dev->name = "iMX6UL TouchScreen Controller";
+	input_dev->id.bustype = BUS_HOST;
+
+	input_dev->open = imx6ul_tsc_open;
+	input_dev->close = imx6ul_tsc_close;
+
+	input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
+	input_set_abs_params(input_dev, ABS_X, 0, 0xFFF, 0, 0);
+	input_set_abs_params(input_dev, ABS_Y, 0, 0xFFF, 0, 0);
+
+	input_set_drvdata(input_dev, tsc);
+
+	tsc->dev = &pdev->dev;
+	tsc->input = input_dev;
+	init_completion(&tsc->completion);
+
+	tsc->xnur_gpio = devm_gpiod_get(&pdev->dev, "xnur", GPIOD_IN);
+	if (IS_ERR(tsc->xnur_gpio)) {
+		err = PTR_ERR(tsc->xnur_gpio);
+		dev_err(&pdev->dev,
+			"failed to request GPIO tsc_X- (xnur): %d\n", err);
+		return err;
+	}
+
+	tsc_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	tsc->tsc_regs = devm_ioremap_resource(&pdev->dev, tsc_mem);
+	if (IS_ERR(tsc->tsc_regs)) {
+		err = PTR_ERR(tsc->tsc_regs);
+		dev_err(&pdev->dev, "failed to remap tsc memory: %d\n", err);
+		return err;
+	}
+
+	adc_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	tsc->adc_regs = devm_ioremap_resource(&pdev->dev, adc_mem);
+	if (IS_ERR(tsc->adc_regs)) {
+		err = PTR_ERR(tsc->adc_regs);
+		dev_err(&pdev->dev, "failed to remap adc memory: %d\n", err);
+		return err;
+	}
+
+	tsc->tsc_clk = devm_clk_get(&pdev->dev, "tsc");
+	if (IS_ERR(tsc->tsc_clk)) {
+		err = PTR_ERR(tsc->tsc_clk);
+		dev_err(&pdev->dev, "failed getting tsc clock: %d\n", err);
+		return err;
+	}
+
+	tsc->adc_clk = devm_clk_get(&pdev->dev, "adc");
+	if (IS_ERR(tsc->adc_clk)) {
+		err = PTR_ERR(tsc->adc_clk);
+		dev_err(&pdev->dev, "failed getting adc clock: %d\n", err);
+		return err;
+	}
+
+	tsc_irq = platform_get_irq(pdev, 0);
+	if (tsc_irq < 0) {
+		dev_err(&pdev->dev, "no tsc irq resource?\n");
+		return tsc_irq;
+	}
+
+	adc_irq = platform_get_irq(pdev, 1);
+	if (adc_irq <= 0) {
+		dev_err(&pdev->dev, "no adc irq resource?\n");
+		return adc_irq;
+	}
+
+	err = devm_request_threaded_irq(tsc->dev, tsc_irq,
+					NULL, tsc_irq_fn, IRQF_ONESHOT,
+					dev_name(&pdev->dev), tsc);
+	if (err) {
+		dev_err(&pdev->dev,
+			"failed requesting tsc irq %d: %d\n",
+			tsc_irq, err);
+		return err;
+	}
+
+	err = devm_request_irq(tsc->dev, adc_irq, adc_irq_fn, 0,
+				dev_name(&pdev->dev), tsc);
+	if (err) {
+		dev_err(&pdev->dev,
+			"failed requesting adc irq %d: %d\n",
+			adc_irq, err);
+		return err;
+	}
+
+	err = of_property_read_u32(np, "measure-delay-time",
+				   &tsc->measure_delay_time);
+	if (err)
+		tsc->measure_delay_time = 0xffff;
+
+	err = of_property_read_u32(np, "pre-charge-time",
+				   &tsc->pre_charge_time);
+	if (err)
+		tsc->pre_charge_time = 0xfff;
+
+	err = input_register_device(tsc->input);
+	if (err) {
+		dev_err(&pdev->dev,
+			"failed to register input device: %d\n", err);
+		return err;
+	}
+
+	platform_set_drvdata(pdev, tsc);
+	return 0;
+}
+
+static int __maybe_unused imx6ul_tsc_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = tsc->input;
+
+	mutex_lock(&input_dev->mutex);
+
+	if (input_dev->users) {
+		imx6ul_tsc_disable(tsc);
+
+		clk_disable_unprepare(tsc->tsc_clk);
+		clk_disable_unprepare(tsc->adc_clk);
+	}
+
+	mutex_unlock(&input_dev->mutex);
+
+	return 0;
+}
+
+static int __maybe_unused imx6ul_tsc_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = tsc->input;
+	int retval = 0;
+
+	mutex_lock(&input_dev->mutex);
+
+	if (input_dev->users) {
+		retval = clk_prepare_enable(tsc->adc_clk);
+		if (retval)
+			goto out;
+
+		retval = clk_prepare_enable(tsc->tsc_clk);
+		if (retval) {
+			clk_disable_unprepare(tsc->adc_clk);
+			goto out;
+		}
+
+		imx6ul_tsc_init(tsc);
+	}
+
+out:
+	mutex_unlock(&input_dev->mutex);
+	return retval;
+}
+
+static SIMPLE_DEV_PM_OPS(imx6ul_tsc_pm_ops,
+			 imx6ul_tsc_suspend, imx6ul_tsc_resume);
+
+static const struct of_device_id imx6ul_tsc_match[] = {
+	{ .compatible = "fsl,imx6ul-tsc", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx6ul_tsc_match);
+
+static struct platform_driver imx6ul_tsc_driver = {
+	.driver		= {
+		.name	= "imx6ul-tsc",
+		.of_match_table	= imx6ul_tsc_match,
+		.pm	= &imx6ul_tsc_pm_ops,
+	},
+	.probe		= imx6ul_tsc_probe,
+};
+module_platform_driver(imx6ul_tsc_driver);
+
+MODULE_AUTHOR("Haibo Chen <haibo.chen@freescale.com>");
+MODULE_DESCRIPTION("Freescale i.MX6UL Touchscreen controller driver");
+MODULE_LICENSE("GPL v2");