1 files changed, 295 insertions, 180 deletions

diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c
index 948e167557f..1bf9906b5a3 100644
--- a/drivers/input/touchscreen/tsc2007.c
+++ b/drivers/input/touchscreen/tsc2007.c
@@ -21,15 +21,14 @@
  */
 
 #include <linux/module.h>
-#include <linux/hrtimer.h>
 #include <linux/slab.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
 #include <linux/i2c/tsc2007.h>
-
-#define TS_POLL_DELAY	(10 * 1000)	/* ns delay before the first sample */
-#define TS_POLL_PERIOD	(5 * 1000)	/* ns delay between samples */
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
 
 #define TSC2007_MEASURE_TEMP0		(0x0 << 4)
 #define TSC2007_MEASURE_AUX		(0x2 << 4)
@@ -70,20 +69,24 @@ struct ts_event {
 struct tsc2007 {
 	struct input_dev	*input;
 	char			phys[32];
-	struct hrtimer		timer;
-	struct ts_event		tc;
 
 	struct i2c_client	*client;
 
-	spinlock_t		lock;
-
 	u16			model;
 	u16			x_plate_ohms;
+	u16			max_rt;
+	unsigned long		poll_period;
+	int			fuzzx;
+	int			fuzzy;
+	int			fuzzz;
 
-	unsigned		pendown;
+	unsigned		gpio;
 	int			irq;
 
-	int			(*get_pendown_state)(void);
+	wait_queue_head_t	wait;
+	bool			stopped;
+
+	int			(*get_pendown_state)(struct device *);
 	void			(*clear_penirq)(void);
 };
 
@@ -109,186 +112,300 @@ static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
 	return val;
 }
 
-static void tsc2007_send_event(void *tsc)
+static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
 {
-	struct tsc2007	*ts = tsc;
-	u32		rt;
-	u16		x, y, z1, z2;
+	/* y- still on; turn on only y+ (and ADC) */
+	tc->y = tsc2007_xfer(tsc, READ_Y);
 
-	x = ts->tc.x;
-	y = ts->tc.y;
-	z1 = ts->tc.z1;
-	z2 = ts->tc.z2;
+	/* turn y- off, x+ on, then leave in lowpower */
+	tc->x = tsc2007_xfer(tsc, READ_X);
+
+	/* turn y+ off, x- on; we'll use formula #1 */
+	tc->z1 = tsc2007_xfer(tsc, READ_Z1);
+	tc->z2 = tsc2007_xfer(tsc, READ_Z2);
+
+	/* Prepare for next touch reading - power down ADC, enable PENIRQ */
+	tsc2007_xfer(tsc, PWRDOWN);
+}
+
+static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
+{
+	u32 rt = 0;
 
 	/* range filtering */
-	if (x == MAX_12BIT)
-		x = 0;
+	if (tc->x == MAX_12BIT)
+		tc->x = 0;
 
-	if (likely(x && z1)) {
+	if (likely(tc->x && tc->z1)) {
 		/* compute touch pressure resistance using equation #1 */
-		rt = z2;
-		rt -= z1;
-		rt *= x;
-		rt *= ts->x_plate_ohms;
-		rt /= z1;
+		rt = tc->z2 - tc->z1;
+		rt *= tc->x;
+		rt *= tsc->x_plate_ohms;
+		rt /= tc->z1;
 		rt = (rt + 2047) >> 12;
-	} else
-		rt = 0;
-
-	/* Sample found inconsistent by debouncing or pressure is beyond
-	 * the maximum. Don't report it to user space, repeat at least
-	 * once more the measurement
-	 */
-	if (rt > MAX_12BIT) {
-		dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
-
-		hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
-			      HRTIMER_MODE_REL);
-		return;
 	}
 
-	/* NOTE: We can't rely on the pressure to determine the pen down
-	 * state, even this controller has a pressure sensor.  The pressure
-	 * value can fluctuate for quite a while after lifting the pen and
-	 * in some cases may not even settle at the expected value.
+	return rt;
+}
+
+static bool tsc2007_is_pen_down(struct tsc2007 *ts)
+{
+	/*
+	 * NOTE: We can't rely on the pressure to determine the pen down
+	 * state, even though this controller has a pressure sensor.
+	 * The pressure value can fluctuate for quite a while after
+	 * lifting the pen and in some cases may not even settle at the
+	 * expected value.
 	 *
 	 * The only safe way to check for the pen up condition is in the
-	 * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
+	 * work function by reading the pen signal state (it's a GPIO
+	 * and IRQ). Unfortunately such callback is not always available,
+	 * in that case we assume that the pen is down and expect caller
+	 * to fall back on the pressure reading.
 	 */
-	if (rt) {
-		struct input_dev *input = ts->input;
 
-		if (!ts->pendown) {
-			dev_dbg(&ts->client->dev, "DOWN\n");
+	if (!ts->get_pendown_state)
+		return true;
 
-			input_report_key(input, BTN_TOUCH, 1);
-			ts->pendown = 1;
+	return ts->get_pendown_state(&ts->client->dev);
+}
+
+static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
+{
+	struct tsc2007 *ts = handle;
+	struct input_dev *input = ts->input;
+	struct ts_event tc;
+	u32 rt;
+
+	while (!ts->stopped && tsc2007_is_pen_down(ts)) {
+
+		/* pen is down, continue with the measurement */
+		tsc2007_read_values(ts, &tc);
+
+		rt = tsc2007_calculate_pressure(ts, &tc);
+
+		if (!rt && !ts->get_pendown_state) {
+			/*
+			 * If pressure reported is 0 and we don't have
+			 * callback to check pendown state, we have to
+			 * assume that pen was lifted up.
+			 */
+			break;
 		}
 
-		input_report_abs(input, ABS_X, x);
-		input_report_abs(input, ABS_Y, y);
-		input_report_abs(input, ABS_PRESSURE, rt);
+		if (rt <= ts->max_rt) {
+			dev_dbg(&ts->client->dev,
+				"DOWN point(%4d,%4d), pressure (%4u)\n",
+				tc.x, tc.y, rt);
 
-		input_sync(input);
+			input_report_key(input, BTN_TOUCH, 1);
+			input_report_abs(input, ABS_X, tc.x);
+			input_report_abs(input, ABS_Y, tc.y);
+			input_report_abs(input, ABS_PRESSURE, rt);
+
+			input_sync(input);
+
+		} else {
+			/*
+			 * Sample found inconsistent by debouncing or pressure is
+			 * beyond the maximum. Don't report it to user space,
+			 * repeat at least once more the measurement.
+			 */
+			dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
+		}
 
-		dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n",
-			x, y, rt);
+		wait_event_timeout(ts->wait, ts->stopped,
+				   msecs_to_jiffies(ts->poll_period));
 	}
 
-	hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
-			HRTIMER_MODE_REL);
+	dev_dbg(&ts->client->dev, "UP\n");
+
+	input_report_key(input, BTN_TOUCH, 0);
+	input_report_abs(input, ABS_PRESSURE, 0);
+	input_sync(input);
+
+	if (ts->clear_penirq)
+		ts->clear_penirq();
+
+	return IRQ_HANDLED;
 }
 
-static int tsc2007_read_values(struct tsc2007 *tsc)
+static irqreturn_t tsc2007_hard_irq(int irq, void *handle)
 {
-	/* y- still on; turn on only y+ (and ADC) */
-	tsc->tc.y = tsc2007_xfer(tsc, READ_Y);
+	struct tsc2007 *ts = handle;
 
-	/* turn y- off, x+ on, then leave in lowpower */
-	tsc->tc.x = tsc2007_xfer(tsc, READ_X);
+	if (tsc2007_is_pen_down(ts))
+		return IRQ_WAKE_THREAD;
 
-	/* turn y+ off, x- on; we'll use formula #1 */
-	tsc->tc.z1 = tsc2007_xfer(tsc, READ_Z1);
-	tsc->tc.z2 = tsc2007_xfer(tsc, READ_Z2);
+	if (ts->clear_penirq)
+		ts->clear_penirq();
 
-	/* power down */
-	tsc2007_xfer(tsc, PWRDOWN);
+	return IRQ_HANDLED;
+}
+
+static void tsc2007_stop(struct tsc2007 *ts)
+{
+	ts->stopped = true;
+	mb();
+	wake_up(&ts->wait);
+
+	disable_irq(ts->irq);
+}
+
+static int tsc2007_open(struct input_dev *input_dev)
+{
+	struct tsc2007 *ts = input_get_drvdata(input_dev);
+	int err;
+
+	ts->stopped = false;
+	mb();
+
+	enable_irq(ts->irq);
+
+	/* Prepare for touch readings - power down ADC and enable PENIRQ */
+	err = tsc2007_xfer(ts, PWRDOWN);
+	if (err < 0) {
+		tsc2007_stop(ts);
+		return err;
+	}
 
 	return 0;
 }
 
-static enum hrtimer_restart tsc2007_timer(struct hrtimer *handle)
+static void tsc2007_close(struct input_dev *input_dev)
+{
+	struct tsc2007 *ts = input_get_drvdata(input_dev);
+
+	tsc2007_stop(ts);
+}
+
+#ifdef CONFIG_OF
+static int tsc2007_get_pendown_state_gpio(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct tsc2007 *ts = i2c_get_clientdata(client);
+
+	return !gpio_get_value(ts->gpio);
+}
+
+static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
 {
-	struct tsc2007 *ts = container_of(handle, struct tsc2007, timer);
-	unsigned long flags;
+	struct device_node *np = client->dev.of_node;
+	u32 val32;
+	u64 val64;
 
-	spin_lock_irqsave(&ts->lock, flags);
+	if (!np) {
+		dev_err(&client->dev, "missing device tree data\n");
+		return -EINVAL;
+	}
 
-	if (unlikely(!ts->get_pendown_state() && ts->pendown)) {
-		struct input_dev *input = ts->input;
+	if (!of_property_read_u32(np, "ti,max-rt", &val32))
+		ts->max_rt = val32;
+	else
+		ts->max_rt = MAX_12BIT;
 
-		dev_dbg(&ts->client->dev, "UP\n");
+	if (!of_property_read_u32(np, "ti,fuzzx", &val32))
+		ts->fuzzx = val32;
 
-		input_report_key(input, BTN_TOUCH, 0);
-		input_report_abs(input, ABS_PRESSURE, 0);
-		input_sync(input);
+	if (!of_property_read_u32(np, "ti,fuzzy", &val32))
+		ts->fuzzy = val32;
 
-		ts->pendown = 0;
-		enable_irq(ts->irq);
-	} else {
-		/* pen is still down, continue with the measurement */
-		dev_dbg(&ts->client->dev, "pen is still down\n");
+	if (!of_property_read_u32(np, "ti,fuzzz", &val32))
+		ts->fuzzz = val32;
 
-		tsc2007_read_values(ts);
-		tsc2007_send_event(ts);
+	if (!of_property_read_u64(np, "ti,poll-period", &val64))
+		ts->poll_period = val64;
+	else
+		ts->poll_period = 1;
+
+	if (!of_property_read_u32(np, "ti,x-plate-ohms", &val32)) {
+		ts->x_plate_ohms = val32;
+	} else {
+		dev_err(&client->dev, "missing ti,x-plate-ohms devicetree property.");
+		return -EINVAL;
 	}
 
-	spin_unlock_irqrestore(&ts->lock, flags);
+	ts->gpio = of_get_gpio(np, 0);
+	if (gpio_is_valid(ts->gpio))
+		ts->get_pendown_state = tsc2007_get_pendown_state_gpio;
+	else
+		dev_warn(&client->dev,
+			 "GPIO not specified in DT (of_get_gpio returned %d)\n",
+			 ts->gpio);
 
-	return HRTIMER_NORESTART;
+	return 0;
 }
-
-static irqreturn_t tsc2007_irq(int irq, void *handle)
+#else
+static int tsc2007_probe_dt(struct i2c_client *client, struct tsc2007 *ts)
 {
-	struct tsc2007 *ts = handle;
-	unsigned long flags;
+	dev_err(&client->dev, "platform data is required!\n");
+	return -EINVAL;
+}
+#endif
 
-	spin_lock_irqsave(&ts->lock, flags);
+static int tsc2007_probe_pdev(struct i2c_client *client, struct tsc2007 *ts,
+			      const struct tsc2007_platform_data *pdata,
+			      const struct i2c_device_id *id)
+{
+	ts->model             = pdata->model;
+	ts->x_plate_ohms      = pdata->x_plate_ohms;
+	ts->max_rt            = pdata->max_rt ? : MAX_12BIT;
+	ts->poll_period       = pdata->poll_period ? : 1;
+	ts->get_pendown_state = pdata->get_pendown_state;
+	ts->clear_penirq      = pdata->clear_penirq;
+	ts->fuzzx             = pdata->fuzzx;
+	ts->fuzzy             = pdata->fuzzy;
+	ts->fuzzz             = pdata->fuzzz;
 
-	if (likely(ts->get_pendown_state())) {
-		disable_irq_nosync(ts->irq);
-		hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
-					HRTIMER_MODE_REL);
+	if (pdata->x_plate_ohms == 0) {
+		dev_err(&client->dev, "x_plate_ohms is not set up in platform data");
+		return -EINVAL;
 	}
 
-	if (ts->clear_penirq)
-		ts->clear_penirq();
+	return 0;
+}
 
-	spin_unlock_irqrestore(&ts->lock, flags);
+static void tsc2007_call_exit_platform_hw(void *data)
+{
+	struct device *dev = data;
+	const struct tsc2007_platform_data *pdata = dev_get_platdata(dev);
 
-	return IRQ_HANDLED;
+	pdata->exit_platform_hw();
 }
 
 static int tsc2007_probe(struct i2c_client *client,
-			const struct i2c_device_id *id)
+			 const struct i2c_device_id *id)
 {
+	const struct tsc2007_platform_data *pdata = dev_get_platdata(&client->dev);
 	struct tsc2007 *ts;
-	struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data;
 	struct input_dev *input_dev;
 	int err;
 
-	if (!pdata) {
-		dev_err(&client->dev, "platform data is required!\n");
-		return -EINVAL;
-	}
-
 	if (!i2c_check_functionality(client->adapter,
 				     I2C_FUNC_SMBUS_READ_WORD_DATA))
 		return -EIO;
 
-	ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL);
-	input_dev = input_allocate_device();
-	if (!ts || !input_dev) {
-		err = -ENOMEM;
-		goto err_free_mem;
-	}
-
-	ts->client = client;
-	i2c_set_clientdata(client, ts);
-
-	ts->input = input_dev;
+	ts = devm_kzalloc(&client->dev, sizeof(struct tsc2007), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
 
-	hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	ts->timer.function = tsc2007_timer;
+	if (pdata)
+		err = tsc2007_probe_pdev(client, ts, pdata, id);
+	else
+		err = tsc2007_probe_dt(client, ts);
+	if (err)
+		return err;
 
-	spin_lock_init(&ts->lock);
+	input_dev = devm_input_allocate_device(&client->dev);
+	if (!input_dev)
+		return -ENOMEM;
 
-	ts->model             = pdata->model;
-	ts->x_plate_ohms      = pdata->x_plate_ohms;
-	ts->get_pendown_state = pdata->get_pendown_state;
-	ts->clear_penirq      = pdata->clear_penirq;
+	i2c_set_clientdata(client, ts);
 
-	pdata->init_platform_hw();
+	ts->client = client;
+	ts->irq = client->irq;
+	ts->input = input_dev;
+	init_waitqueue_head(&ts->wait);
 
 	snprintf(ts->phys, sizeof(ts->phys),
 		 "%s/input0", dev_name(&client->dev));
@@ -297,86 +414,84 @@ static int tsc2007_probe(struct i2c_client *client,
 	input_dev->phys = ts->phys;
 	input_dev->id.bustype = BUS_I2C;
 
-	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
-	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+	input_dev->open = tsc2007_open;
+	input_dev->close = tsc2007_close;
 
-	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
-	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
-	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
+	input_set_drvdata(input_dev, ts);
 
-	tsc2007_read_values(ts);
+	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 
-	ts->irq = client->irq;
+	input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, ts->fuzzx, 0);
+	input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, ts->fuzzy, 0);
+	input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT,
+			     ts->fuzzz, 0);
+
+	if (pdata) {
+		if (pdata->exit_platform_hw) {
+			err = devm_add_action(&client->dev,
+					      tsc2007_call_exit_platform_hw,
+					      &client->dev);
+			if (err) {
+				dev_err(&client->dev,
+					"Failed to register exit_platform_hw action, %d\n",
+					err);
+				return err;
+			}
+		}
 
-	err = request_irq(ts->irq, tsc2007_irq, 0,
-			client->dev.driver->name, ts);
-	if (err < 0) {
-		dev_err(&client->dev, "irq %d busy?\n", ts->irq);
-		goto err_free_mem;
+		if (pdata->init_platform_hw)
+			pdata->init_platform_hw();
 	}
 
-	err = input_register_device(input_dev);
-	if (err)
-		goto err_free_irq;
-
-	dev_info(&client->dev, "registered with irq (%d)\n", ts->irq);
-
-	return 0;
-
- err_free_irq:
-	free_irq(ts->irq, ts);
-	hrtimer_cancel(&ts->timer);
- err_free_mem:
-	input_free_device(input_dev);
-	kfree(ts);
-	return err;
-}
-
-static int tsc2007_remove(struct i2c_client *client)
-{
-	struct tsc2007	*ts = i2c_get_clientdata(client);
-	struct tsc2007_platform_data *pdata;
+	err = devm_request_threaded_irq(&client->dev, ts->irq,
+					tsc2007_hard_irq, tsc2007_soft_irq,
+					IRQF_ONESHOT,
+					client->dev.driver->name, ts);
+	if (err) {
+		dev_err(&client->dev, "Failed to request irq %d: %d\n",
+			ts->irq, err);
+		return err;
+	}
 
-	pdata = client->dev.platform_data;
-	pdata->exit_platform_hw();
+	tsc2007_stop(ts);
 
-	free_irq(ts->irq, ts);
-	hrtimer_cancel(&ts->timer);
-	input_unregister_device(ts->input);
-	kfree(ts);
+	err = input_register_device(input_dev);
+	if (err) {
+		dev_err(&client->dev,
+			"Failed to register input device: %d\n", err);
+		return err;
+	}
 
 	return 0;
 }
 
-static struct i2c_device_id tsc2007_idtable[] = {
+static const struct i2c_device_id tsc2007_idtable[] = {
 	{ "tsc2007", 0 },
 	{ }
 };
 
 MODULE_DEVICE_TABLE(i2c, tsc2007_idtable);
 
+#ifdef CONFIG_OF
+static const struct of_device_id tsc2007_of_match[] = {
+	{ .compatible = "ti,tsc2007" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, tsc2007_of_match);
+#endif
+
 static struct i2c_driver tsc2007_driver = {
 	.driver = {
 		.owner	= THIS_MODULE,
-		.name	= "tsc2007"
+		.name	= "tsc2007",
+		.of_match_table = of_match_ptr(tsc2007_of_match),
 	},
 	.id_table	= tsc2007_idtable,
 	.probe		= tsc2007_probe,
-	.remove		= tsc2007_remove,
 };
 
-static int __init tsc2007_init(void)
-{
-	return i2c_add_driver(&tsc2007_driver);
-}
-
-static void __exit tsc2007_exit(void)
-{
-	i2c_del_driver(&tsc2007_driver);
-}
-
-module_init(tsc2007_init);
-module_exit(tsc2007_exit);
+module_i2c_driver(tsc2007_driver);
 
 MODULE_AUTHOR("Kwangwoo Lee <kwlee@mtekvision.com>");
 MODULE_DESCRIPTION("TSC2007 TouchScreen Driver");