GENERIC:input: Dynamic enable or disable for the bu21013 touch screen

Added support for dynamic enable or disable for the bu21013 controller
events and external clock using sysfs.
enable command:
echo 1 > /sys/devices/platform/nmk-i2c.3/i2c-3/3-005c/enable
disable command:
echo 0 > /sys/devices/platform/nmk-i2c.3/i2c-3/3-005c/enable
enable external clock:
echo 1 > /sys/devices/platform/nmk-i2c.3/i2c-3/3-005c/ext_clk
disable external clock:
echo 0 > /sys/devices/platform/nmk-i2c.3/i2c-3/3-005c/ext_clk

ST-Ericsson Id: WP 273488

Change-Id: I89329cdebe9784ff3d32119ebe0976a56ca0e4d0
Signed-off-by: Srikanth Shivanand <srikanth.shivanand@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/7225
Tested-by: Naveen Kumar GADDIPATI <naveen.gaddipati@stericsson.com>
Reviewed-by: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>

1 files changed, 240 insertions, 164 deletions

diff --git a/drivers/input/touchscreen/bu21013_ts.c b/drivers/input/touchscreen/bu21013_ts.c
index da9cd0ad15f..efe1b01679f 100644
--- a/drivers/input/touchscreen/bu21013_ts.c
+++ b/drivers/input/touchscreen/bu21013_ts.c
@@ -15,6 +15,8 @@
 #include <linux/timer.h>
 #include <linux/input/bu21013.h>
 #include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+#include <linux/clk.h>
 
 #define PEN_DOWN_INTR	0
 #define PEN_UP_INTR	1
@@ -24,7 +26,7 @@
 #define MAX_TOUCH_MAJOR	255
 #define MAX_TOUCH_MINOR	15
 #define MAX_PRESSURE	1
-#define PENUP_TIMEOUT	(2)
+#define PENUP_TIMEOUT	(2)/* 2msecs */
 #define SCALE_FACTOR	1000
 #define DELTA_MIN	16
 #define MASK_BITS	0x03
@@ -49,8 +51,10 @@
  * @factor_x: x scale factor
  * @factor_y: y scale factor
  * @previous_press_reported: last reported flag
- * @touchp_kobj: pointer to kernel object for touch panel
  * @penup_timer: timeout value
+ * @regulator: pointer to the Regulator used for touch screen controller
+ * @tpclk: pointer to clock structure
+ * @enable: variable to indicate the enable/disable of touch screen
  *
  * Touch panel data structure
  */
@@ -67,126 +71,221 @@ struct bu21013_ts_data {
 	int	factor_x;
 	int	factor_y;
 	bool previous_press_reported;
-	struct kobject *touchp_kobj;
 	int penup_timer;
+	struct regulator *regulator;
+	struct clk *tpclk;
+	bool enable;
 };
 
-/* Global variable to maintain the sys data for two controllers */
-struct bu21013_ts_data *tp1_sys_data, *tp2_sys_data;
-
 static int bu21013_init_chip(struct bu21013_ts_data *data);
 
-/*
- * sysfs is used to change the touchpanel1 parameters
- * and also enable the external clock dynamically
+/**
+ * bu21013_extclk_en() - enable the external clock
+ * @pdata:touch screen data
+ *
+ * This function used to enable the external clock for driver
+ * and returns integer
  */
-static ssize_t touchp1_attr_show(struct kobject *kobj,
-				struct attribute *attr, char *buf)
+static int bu21013_extclk_en(struct bu21013_ts_data *pdata)
 {
-	u8 timeout;
-	u8 sys_ext_clock;
+	int retval;
+
+	if (pdata->tpclk && pdata->chip->ext_clk) {
+		retval = clk_enable(pdata->tpclk);
+		if (retval < 0)
+			return retval;
+	}
 
-	if (strcmp(attr->name, "timeout_value") == 0) {
-		timeout = tp1_sys_data->penup_timer;
-		sprintf(buf, "%d\n", timeout);
-	} else if (strcmp(attr->name, "ext_clk") == 0) {
-		sys_ext_clock = tp1_sys_data->chip->ext_clk;
-		sprintf(buf, "%d\n", sys_ext_clock);
+	retval = bu21013_init_chip(pdata);
+	if (retval < 0) {
+		dev_err(&pdata->client->dev, "chip config failed\n");
+		return retval;
 	}
-	return strlen(buf);
+
+	return 0;
 }
-static ssize_t touchp1_attr_store(struct kobject *kobj,
-			struct attribute *attr, const char *buf, size_t len)
+
+/**
+ * bu21013_extclk_dis() - disable the external clock
+ * @pdata:touch screen data
+ *
+ * This function used to disable the external clock for driver
+ * and returns none
+ */
+static void bu21013_extclk_dis(struct bu21013_ts_data *pdata)
 {
-	int ret = 0;
-	int timeout;
-	int sys_ext_clock;
-
-	if (strcmp(attr->name, "timeout_value") == 0) {
-		ret = sscanf(buf, "%d", &timeout);
-		if (ret == 1)
-			tp1_sys_data->penup_timer = timeout;
-	} else if (strcmp(attr->name, "ext_clk") == 0) {
-		ret = sscanf(buf, "%d", &sys_ext_clock);
-		if ((ret == 1) &&
-			(tp1_sys_data->chip->ext_clk != sys_ext_clock)) {
-			tp1_sys_data->chip->ext_clk = sys_ext_clock;
-			bu21013_init_chip(tp1_sys_data);
-		}
+	int retval;
+
+	clk_disable(pdata->tpclk);
+	pdata->chip->ext_clk = false;
+	retval = bu21013_init_chip(pdata);
+	if (retval < 0)
+		dev_err(&pdata->client->dev, "chip config failed\n");
+}
+/**
+ * bu21013_enable() - enable the touch driver event
+ * @pdata:touch screen data
+ *
+ * This function used to enable the driver and returns integer
+ */
+static int bu21013_enable(struct bu21013_ts_data *pdata)
+{
+	int retval;
+
+	if (pdata->regulator)
+		regulator_enable(pdata->regulator);
+
+	retval = bu21013_extclk_en(pdata);
+	if (retval < 0) {
+		dev_err(&pdata->client->dev, "enable clock failed\n");
+		return retval;
 	}
-	return ret == 1 ? len : -EINVAL;
+
+	enable_irq(pdata->chip->irq);
+
+	return 0;
 }
 
-/*
- * sysfs is used to change the touchpanel2 parameters
- * and also enable the external clock dynamically
+/**
+ * bu21013_enable() - disable the touch driver event
+ * @pdata:touch screen data
+ *
+ * This function used to disable the driver and returns integer
  */
-static ssize_t touchp2_attr_show(struct kobject *kobj,
-				struct attribute *attr, char *buf)
+static void bu21013_disable(struct bu21013_ts_data *pdata)
 {
-	u8 timeout;
-	u8 sys_ext_clock;
+	if (pdata->tpclk && pdata->chip->ext_clk)
+		bu21013_extclk_dis(pdata);
+	disable_irq(pdata->chip->irq);
+	if (pdata->regulator)
+		regulator_disable(pdata->regulator);
+}
 
-	if (strcmp(attr->name, "timeout_value") == 0) {
-		timeout = tp2_sys_data->penup_timer;
-		sprintf(buf, "%d\n", timeout);
-	} else if (strcmp(attr->name, "ext_clk") == 0) {
-		sys_ext_clock = tp2_sys_data->chip->ext_clk;
-		sprintf(buf, "%d\n", sys_ext_clock);
-	}
-	return strlen(buf);
+/**
+ * bu21013_show_attr_enable() - show the touch screen controller status
+ * @dev: pointer to device structure
+ * @attr: pointer to device attribute
+ * @buf: parameter buffer
+ *
+ * This funtion is used to show whether the touch screen is enabled or
+ * disabled
+ */
+static ssize_t bu21013_show_attr_enable(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct bu21013_ts_data *pdata = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", pdata->enable);
 }
-static ssize_t touchp2_attr_store(struct kobject *kobj,
-			struct attribute *attr, const char *buf, size_t len)
+
+/**
+ * bu21013_show_attr_enable() - Enable/Disable the touchscreen.
+ * @dev: pointer to device structure
+ * @attr: pointer to device attribute
+ * @buf: parameter buffer
+ * @count: number of parameters
+ *
+ * This funtion is used to enable or disable the touch screen controller.
+ */
+static ssize_t bu21013_store_attr_enable(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
 {
 	int ret = 0;
-	int timeout;
-	int sys_ext_clock;
-
-	if (strcmp(attr->name, "timeout_value") == 0) {
-		ret = sscanf(buf, "%d", &timeout);
-		if (ret == 1)
-			tp2_sys_data->penup_timer = timeout;
-	} else if (strcmp(attr->name, "ext_clk") == 0) {
-		ret = sscanf(buf, "%d", &sys_ext_clock);
-		if ((ret == 1) &&
-			(tp2_sys_data->chip->ext_clk != sys_ext_clock)) {
-			tp2_sys_data->chip->ext_clk = sys_ext_clock;
-			bu21013_init_chip(tp2_sys_data);
+	unsigned long val;
+
+	struct bu21013_ts_data *pdata = dev_get_drvdata(dev);
+
+	if (strict_strtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if ((val != 0) && (val != 1))
+		return -EINVAL;
+
+	if (pdata->enable != val) {
+		pdata->enable = val ? true : false;
+		if (pdata->enable) {
+			ret = bu21013_enable(pdata);
+			if (ret < 0)
+				return ret;
+		} else
+			bu21013_disable(pdata);
+	}
+	return count;
+}
+
+/**
+ * bu21013_show_attr_enable() - shows the external clock status
+ * @dev: pointer to device structure
+ * @attr: pointer to device attribute
+ * @buf: parameter buffer
+ *
+ * This funtion is used to show whether the external clock for the touch
+ * screen is enabled or disabled disabled.
+ */
+static ssize_t bu21013_show_attr_extclk(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct bu21013_ts_data *pdata = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", pdata->chip->ext_clk);
+}
+
+/**
+ * bu21013_show_attr_enable() - Enable/Disable the external clock
+ * for the tocuh screen controller.
+ * @dev: pointer to device structure
+ * @attr: pointer to device attribute
+ * @buf: parameter buffer
+ * @count: number of parameters
+ *
+ * This funtion is used enabled or disable the external clock for the touch
+ * screen controller.
+ */
+static ssize_t bu21013_store_attr_extclk(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	int retval = 0;
+	struct bu21013_ts_data *pdata = dev_get_drvdata(dev);
+	unsigned long val;
+
+	if (strict_strtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if ((val != 0) && (val != 1))
+		return -EINVAL;
+
+	if (val != pdata->chip->ext_clk) {
+		pdata->chip->ext_clk = val ? true : false;
+		if (pdata->chip->ext_clk) {
+			retval = bu21013_extclk_en(pdata);
+			if (retval < 0) {
+				dev_err(&pdata->client->dev,
+						"enable clock failed\n");
+				return retval;
+			}
+		} else {
+			if (pdata->tpclk)
+				bu21013_extclk_dis(pdata);
 		}
 	}
-	return ret == 1 ? len : -EINVAL;
+	return count;
 }
 
+static DEVICE_ATTR(enable, S_IWUSR | S_IRUGO,
+		bu21013_show_attr_enable, bu21013_store_attr_enable);
 
-static struct attribute touchp_timeout = {.name = "timeout_value",
-						.mode = 0666};
-static struct attribute touchp_ext_clk = {.name = "ext_clk", .mode = 0666};
+static DEVICE_ATTR(ext_clk, S_IWUSR | S_IRUGO,
+		bu21013_show_attr_extclk, bu21013_store_attr_extclk);
 
-static struct attribute *touchp_attribute[] = {
-	&touchp_timeout,
-	&touchp_ext_clk,
-	NULL
-};
 
-static const struct sysfs_ops touchp1_sysfs_ops = {
-	.show = touchp1_attr_show,
-	.store = touchp1_attr_store,
+static struct attribute *bu21013_attribute[] = {
+		&dev_attr_enable.attr,
+		&dev_attr_ext_clk.attr,
+		NULL,
 };
 
-static const struct sysfs_ops touchp2_sysfs_ops = {
-	.show = touchp2_attr_show,
-	.store = touchp2_attr_store,
+static struct attribute_group bu21013_attr_group = {
+		.attrs = bu21013_attribute,
 };
 
-static struct kobj_type ktype_touchp1 = {
-	.sysfs_ops = &touchp1_sysfs_ops,
-	.default_attrs = touchp_attribute,
-};
-static struct kobj_type ktype_touchp2 = {
-	.sysfs_ops = &touchp2_sysfs_ops,
-	.default_attrs = touchp_attribute,
-};
 
 /*
  * bu21013_get_number_of_bits() - count the bits in given value
@@ -675,10 +774,7 @@ static int bu21013_suspend(struct i2c_client *client, pm_message_t mesg)
 {
 	struct bu21013_ts_data *bu21013_data = i2c_get_clientdata(client);
 
-	if (device_may_wakeup(&client->dev))
-		enable_irq(bu21013_data->chip->irq);
-	else
-		disable_irq(bu21013_data->chip->irq);
+	bu21013_disable(bu21013_data);
 
 	return 0;
 }
@@ -692,69 +788,13 @@ static int bu21013_suspend(struct i2c_client *client, pm_message_t mesg)
  */
 static int bu21013_resume(struct i2c_client *client)
 {
-	int retval;
 	struct bu21013_ts_data *bu21013_data = i2c_get_clientdata(client);
 
-	retval = bu21013_init_chip(bu21013_data);
-	if (retval < 0) {
-		dev_err(&client->dev, "tsc config failed\n");
-		goto err;
-	}
-
-	if (device_may_wakeup(&client->dev))
-		disable_irq(bu21013_data->chip->irq);
-	else
-		enable_irq(bu21013_data->chip->irq);
-
-	return 0;
-err:
-	kfree(bu21013_data);
-	return retval;
+	return bu21013_enable(bu21013_data);
 }
 #endif
 
 /**
- * bu21013_sysfs() - sys fs parameters
- * @tp_kobj: kernel object structure pointer
- *
- * This function uses to initialize the sysfs for touch panel
- * based on the controller number
- */
-int bu21013_sysfs(struct kobject *tp_kobj , int ctrl)
-{
-	int retval = 0;
-
-	tp_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
-	if (tp_kobj == NULL) {
-		retval = -ENOMEM;
-		goto err;
-	}
-	if (ctrl == 1)
-		tp_kobj->ktype = &ktype_touchp1;
-	else if (ctrl == 2)
-		tp_kobj->ktype = &ktype_touchp2;
-	kobject_init(tp_kobj, tp_kobj->ktype);
-	if (ctrl == 1)
-		retval = kobject_set_name(tp_kobj, "touchp1");
-	else if (ctrl == 2)
-		retval = kobject_set_name(tp_kobj, "touchp2");
-	if (retval) {
-		kfree(tp_kobj);
-		goto err;
-	}
-	if (ctrl == 1)
-		retval = kobject_add(tp_kobj, NULL, "touchp1");
-	else if (ctrl == 2)
-		retval = kobject_add(tp_kobj, NULL, "touchp2");
-	if (retval) {
-		kfree(tp_kobj);
-		goto err;
-	}
-	return 0;
-err:
-	return retval;
-}
-/**
  * bu21013_probe() - initialzes the i2c-client touchscreen driver
  * @i2c: i2c client structure pointer
  * @id:i2c device id pointer
@@ -770,6 +810,7 @@ static int bu21013_probe(struct i2c_client *i2c,
 	struct input_dev *in_dev;
 	short x_max;
 	short y_max;
+
 	struct bu21013_platform_device *pdata = i2c->dev.platform_data;
 
 	if (!pdata) {
@@ -820,6 +861,15 @@ static int bu21013_probe(struct i2c_client *i2c,
 	bu21013_data->penirq_timer.function = bu21013_timer_callback;
 	i2c_set_clientdata(i2c, bu21013_data);
 
+	dev_set_name(&i2c->dev, pdata->name);
+	bu21013_data->regulator = regulator_get(&i2c->dev, "v-touch");
+	if (IS_ERR(bu21013_data->regulator)) {
+		dev_warn(&i2c->dev, "regulator_get failed\n");
+		bu21013_data->regulator = NULL;
+	}
+	if (bu21013_data->regulator)
+		regulator_enable(bu21013_data->regulator);
+
 	/* configure the gpio pins */
 	if (pdata->cs_en) {
 		retval = pdata->cs_en(pdata->cs_pin);
@@ -829,6 +879,18 @@ static int bu21013_probe(struct i2c_client *i2c,
 		}
 	}
 
+	bu21013_data->tpclk = clk_get(&i2c->dev, NULL);
+	if (IS_ERR(bu21013_data->tpclk)) {
+		dev_warn(&i2c->dev, "get extern clock failed\n");
+		bu21013_data->tpclk = NULL;
+	} else if (pdata->ext_clk) {
+		retval = clk_enable(bu21013_data->tpclk);
+		if (retval < 0) {
+			dev_err(&i2c->dev, "clock enable failed\n");
+			goto err_ext_clk;
+		}
+	}
+
 	/* configure the touch panel controller */
 	retval = bu21013_init_chip(bu21013_data);
 	if (retval < 0) {
@@ -871,29 +933,31 @@ static int bu21013_probe(struct i2c_client *i2c,
 		dev_err(&i2c->dev, "request irq %d failed\n", pdata->irq);
 		goto err_init_irq;
 	}
+	bu21013_data->enable = true;
 
-	retval = bu21013_sysfs(bu21013_data->touchp_kobj, pdata->tp_cntl);
-	if (retval)
-		goto err_init_sys;
-	/*
-	 * to maintain the each device data, we are storing
-	 * in global varaiables for tuning the touch screen
-	 */
-	if (pdata->tp_cntl == 1)
-		tp1_sys_data = bu21013_data;
-	else if (pdata->tp_cntl == 2)
-		tp2_sys_data = bu21013_data;
+	/* sysfs implementation for dynamic enable/disable the input event */
+	retval = sysfs_create_group(&i2c->dev.kobj,	&bu21013_attr_group);
+	if (retval) {
+		dev_err(&i2c->dev, "failed to create sysfs entries\n");
+		goto err_sysfs;
+	}
 
 	dev_dbg(&i2c->dev, "init done");
 
 	return retval;
-err_init_sys:
+
+err_sysfs:
 	free_irq(pdata->irq, bu21013_data);
 err_init_irq:
 	input_unregister_device(bu21013_data->in_dev);
 	bu21013_data->in_dev = NULL;
 err_input_register:
 err_init_config:
+	if (bu21013_data->tpclk && pdata->ext_clk) {
+		clk_disable(bu21013_data->tpclk);
+		clk_put(bu21013_data->tpclk);
+	}
+err_ext_clk:
 	pdata->cs_dis(pdata->cs_pin);
 err_init_cs:
 	del_timer_sync(&bu21013_data->penirq_timer);
@@ -904,6 +968,7 @@ err_alloc:
 	kfree(bu21013_data);
 	return retval;
 }
+
 /**
  * bu21013_remove() - removes the i2c-client touchscreen driver
  * @client: i2c client structure pointer
@@ -915,6 +980,8 @@ static int __devexit bu21013_remove(struct i2c_client *client)
 {
 	struct bu21013_ts_data *data = i2c_get_clientdata(client);
 
+	sysfs_remove_group(&client->dev.kobj, &bu21013_attr_group);
+
 	del_timer_sync(&data->penirq_timer);
 	cancel_work_sync(&data->timer_wq_handler);
 	cancel_work_sync(&data->gpio_wq_handler);
@@ -924,6 +991,15 @@ static int __devexit bu21013_remove(struct i2c_client *client)
 		data->chip->cs_dis(data->chip->cs_pin);
 	}
 	input_unregister_device(data->in_dev);
+
+	if (data->tpclk && data->chip->ext_clk) {
+		clk_disable(data->tpclk);
+		clk_put(data->tpclk);
+	}
+	if (data->regulator) {
+		regulator_disable(data->regulator);
+		regulator_put(data->regulator);
+	}
 	kfree(data);
 
 	return 0;