1 files changed, 215 insertions, 131 deletions

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index 14ea54b78e4..da201b8e37d 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -19,17 +19,21 @@
  */
 #include <linux/types.h>
 #include <linux/hwmon.h>
-#include <linux/init.h>
 #include <linux/err.h>
 #include <linux/sched.h>
 #include <linux/delay.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_device.h>
 #include <linux/gpio.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/ads7846.h>
 #include <linux/regulator/consumer.h>
+#include <linux/module.h>
 #include <asm/irq.h>
 
 /*
@@ -96,8 +100,7 @@ struct ads7846 {
 	struct spi_device	*spi;
 	struct regulator	*reg;
 
-#if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE)
-	struct attribute_group	*attr_group;
+#if IS_ENABLED(CONFIG_HWMON)
 	struct device		*hwmon;
 #endif
 
@@ -108,6 +111,7 @@ struct ads7846 {
 	u16			pressure_max;
 
 	bool			swap_xy;
+	bool			use_internal;
 
 	struct ads7846_packet	*packet;
 
@@ -233,7 +237,12 @@ static void __ads7846_disable(struct ads7846 *ts)
 /* Must be called with ts->lock held */
 static void __ads7846_enable(struct ads7846 *ts)
 {
-	regulator_enable(ts->reg);
+	int error;
+
+	error = regulator_enable(ts->reg);
+	if (error != 0)
+		dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error);
+
 	ads7846_restart(ts);
 }
 
@@ -280,17 +289,24 @@ struct ser_req {
 	u8			command;
 	u8			ref_off;
 	u16			scratch;
-	__be16			sample;
 	struct spi_message	msg;
 	struct spi_transfer	xfer[6];
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+	__be16 sample ____cacheline_aligned;
 };
 
 struct ads7845_ser_req {
 	u8			command[3];
-	u8			pwrdown[3];
-	u8			sample[3];
 	struct spi_message	msg;
 	struct spi_transfer	xfer[2];
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+	u8 sample[3] ____cacheline_aligned;
 };
 
 static int ads7846_read12_ser(struct device *dev, unsigned command)
@@ -299,7 +315,6 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
 	struct ads7846 *ts = dev_get_drvdata(dev);
 	struct ser_req *req;
 	int status;
-	int use_internal;
 
 	req = kzalloc(sizeof *req, GFP_KERNEL);
 	if (!req)
@@ -307,11 +322,8 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
 
 	spi_message_init(&req->msg);
 
-	/* FIXME boards with ads7846 might use external vref instead ... */
-	use_internal = (ts->model == 7846);
-
 	/* maybe turn on internal vREF, and let it settle */
-	if (use_internal) {
+	if (ts->use_internal) {
 		req->ref_on = REF_ON;
 		req->xfer[0].tx_buf = &req->ref_on;
 		req->xfer[0].len = 1;
@@ -323,8 +335,14 @@ static int ads7846_read12_ser(struct device *dev, unsigned command)
 		/* for 1uF, settle for 800 usec; no cap, 100 usec.  */
 		req->xfer[1].delay_usecs = ts->vref_delay_usecs;
 		spi_message_add_tail(&req->xfer[1], &req->msg);
+
+		/* Enable reference voltage */
+		command |= ADS_PD10_REF_ON;
 	}
 
+	/* Enable ADC in every case */
+	command |= ADS_PD10_ADC_ON;
+
 	/* take sample */
 	req->command = (u8) command;
 	req->xfer[2].tx_buf = &req->command;
@@ -401,14 +419,14 @@ static int ads7845_read12_ser(struct device *dev, unsigned command)
 	return status;
 }
 
-#if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE)
+#if IS_ENABLED(CONFIG_HWMON)
 
 #define SHOW(name, var, adjust) static ssize_t \
 name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
 { \
 	struct ads7846 *ts = dev_get_drvdata(dev); \
-	ssize_t v = ads7846_read12_ser(dev, \
-			READ_12BIT_SER(var) | ADS_PD10_ALL_ON); \
+	ssize_t v = ads7846_read12_ser(&ts->spi->dev, \
+			READ_12BIT_SER(var)); \
 	if (v < 0) \
 		return v; \
 	return sprintf(buf, "%u\n", adjust(ts, v)); \
@@ -459,48 +477,43 @@ static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v)
 SHOW(in0_input, vaux, vaux_adjust)
 SHOW(in1_input, vbatt, vbatt_adjust)
 
-static struct attribute *ads7846_attributes[] = {
-	&dev_attr_temp0.attr,
-	&dev_attr_temp1.attr,
-	&dev_attr_in0_input.attr,
-	&dev_attr_in1_input.attr,
-	NULL,
-};
-
-static struct attribute_group ads7846_attr_group = {
-	.attrs = ads7846_attributes,
-};
+static umode_t ads7846_is_visible(struct kobject *kobj, struct attribute *attr,
+				  int index)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct ads7846 *ts = dev_get_drvdata(dev);
 
-static struct attribute *ads7843_attributes[] = {
-	&dev_attr_in0_input.attr,
-	&dev_attr_in1_input.attr,
-	NULL,
-};
+	if (ts->model == 7843 && index < 2)	/* in0, in1 */
+		return 0;
+	if (ts->model == 7845 && index != 2)	/* in0 */
+		return 0;
 
-static struct attribute_group ads7843_attr_group = {
-	.attrs = ads7843_attributes,
-};
+	return attr->mode;
+}
 
-static struct attribute *ads7845_attributes[] = {
-	&dev_attr_in0_input.attr,
+static struct attribute *ads7846_attributes[] = {
+	&dev_attr_temp0.attr,		/* 0 */
+	&dev_attr_temp1.attr,		/* 1 */
+	&dev_attr_in0_input.attr,	/* 2 */
+	&dev_attr_in1_input.attr,	/* 3 */
 	NULL,
 };
 
-static struct attribute_group ads7845_attr_group = {
-	.attrs = ads7845_attributes,
+static struct attribute_group ads7846_attr_group = {
+	.attrs = ads7846_attributes,
+	.is_visible = ads7846_is_visible,
 };
+__ATTRIBUTE_GROUPS(ads7846_attr);
 
 static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
 {
-	struct device *hwmon;
-	int err;
-
 	/* hwmon sensors need a reference voltage */
 	switch (ts->model) {
 	case 7846:
 		if (!ts->vref_mv) {
 			dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n");
 			ts->vref_mv = 2500;
+			ts->use_internal = true;
 		}
 		break;
 	case 7845:
@@ -514,43 +527,19 @@ static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
 		break;
 	}
 
-	/* different chips have different sensor groups */
-	switch (ts->model) {
-	case 7846:
-		ts->attr_group = &ads7846_attr_group;
-		break;
-	case 7845:
-		ts->attr_group = &ads7845_attr_group;
-		break;
-	case 7843:
-		ts->attr_group = &ads7843_attr_group;
-		break;
-	default:
-		dev_dbg(&spi->dev, "ADS%d not recognized\n", ts->model);
-		return 0;
-	}
-
-	err = sysfs_create_group(&spi->dev.kobj, ts->attr_group);
-	if (err)
-		return err;
+	ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias,
+						      ts, ads7846_attr_groups);
+	if (IS_ERR(ts->hwmon))
+		return PTR_ERR(ts->hwmon);
 
-	hwmon = hwmon_device_register(&spi->dev);
-	if (IS_ERR(hwmon)) {
-		sysfs_remove_group(&spi->dev.kobj, ts->attr_group);
-		return PTR_ERR(hwmon);
-	}
-
-	ts->hwmon = hwmon;
 	return 0;
 }
 
 static void ads784x_hwmon_unregister(struct spi_device *spi,
 				     struct ads7846 *ts)
 {
-	if (ts->hwmon) {
-		sysfs_remove_group(&spi->dev.kobj, ts->attr_group);
+	if (ts->hwmon)
 		hwmon_device_unregister(ts->hwmon);
-	}
 }
 
 #else
@@ -589,10 +578,12 @@ static ssize_t ads7846_disable_store(struct device *dev,
 				     const char *buf, size_t count)
 {
 	struct ads7846 *ts = dev_get_drvdata(dev);
-	unsigned long i;
+	unsigned int i;
+	int err;
 
-	if (strict_strtoul(buf, 10, &i))
-		return -EINVAL;
+	err = kstrtouint(buf, 10, &i);
+	if (err)
+		return err;
 
 	if (i)
 		ads7846_disable(ts);
@@ -715,7 +706,7 @@ static void ads7846_read_state(struct ads7846 *ts)
 		m = &ts->msg[msg_idx];
 		error = spi_sync(ts->spi, m);
 		if (error) {
-			dev_err(&ts->spi->dev, "spi_async --> %d\n", error);
+			dev_err(&ts->spi->dev, "spi_sync --> %d\n", error);
 			packet->tc.ignore = true;
 			return;
 		}
@@ -892,9 +883,10 @@ static irqreturn_t ads7846_irq(int irq, void *handle)
 	return IRQ_HANDLED;
 }
 
-static int ads7846_suspend(struct spi_device *spi, pm_message_t message)
+#ifdef CONFIG_PM_SLEEP
+static int ads7846_suspend(struct device *dev)
 {
-	struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+	struct ads7846 *ts = dev_get_drvdata(dev);
 
 	mutex_lock(&ts->lock);
 
@@ -914,9 +906,9 @@ static int ads7846_suspend(struct spi_device *spi, pm_message_t message)
 	return 0;
 }
 
-static int ads7846_resume(struct spi_device *spi)
+static int ads7846_resume(struct device *dev)
 {
-	struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+	struct ads7846 *ts = dev_get_drvdata(dev);
 
 	mutex_lock(&ts->lock);
 
@@ -935,34 +927,44 @@ static int ads7846_resume(struct spi_device *spi)
 
 	return 0;
 }
+#endif
 
-static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads7846 *ts)
+static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume);
+
+static int ads7846_setup_pendown(struct spi_device *spi,
+				 struct ads7846 *ts,
+				 const struct ads7846_platform_data *pdata)
 {
-	struct ads7846_platform_data *pdata = spi->dev.platform_data;
 	int err;
 
-	/* REVISIT when the irq can be triggered active-low, or if for some
+	/*
+	 * REVISIT when the irq can be triggered active-low, or if for some
 	 * reason the touchscreen isn't hooked up, we don't need to access
 	 * the pendown state.
 	 */
-	if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
-		dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
-		return -EINVAL;
-	}
 
 	if (pdata->get_pendown_state) {
 		ts->get_pendown_state = pdata->get_pendown_state;
-		return 0;
-	}
+	} else if (gpio_is_valid(pdata->gpio_pendown)) {
+
+		err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN,
+				       "ads7846_pendown");
+		if (err) {
+			dev_err(&spi->dev,
+				"failed to request/setup pendown GPIO%d: %d\n",
+				pdata->gpio_pendown, err);
+			return err;
+		}
 
-	err = gpio_request(pdata->gpio_pendown, "ads7846_pendown");
-	if (err) {
-		dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
-			pdata->gpio_pendown);
-		return err;
-	}
+		ts->gpio_pendown = pdata->gpio_pendown;
 
-	ts->gpio_pendown = pdata->gpio_pendown;
+		if (pdata->gpio_pendown_debounce)
+			gpio_set_debounce(pdata->gpio_pendown,
+					  pdata->gpio_pendown_debounce);
+	} else {
+		dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
+		return -EINVAL;
+	}
 
 	return 0;
 }
@@ -971,8 +973,8 @@ static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads784
  * Set up the transfers to read touchscreen state; this assumes we
  * use formula #2 for pressure, not #3.
  */
-static void __devinit ads7846_setup_spi_msg(struct ads7846 *ts,
-				const struct ads7846_platform_data *pdata)
+static void ads7846_setup_spi_msg(struct ads7846 *ts,
+				  const struct ads7846_platform_data *pdata)
 {
 	struct spi_message *m = &ts->msg[0];
 	struct spi_transfer *x = ts->xfer;
@@ -1170,33 +1172,107 @@ static void __devinit ads7846_setup_spi_msg(struct ads7846 *ts,
 	spi_message_add_tail(x, m);
 }
 
-static int __devinit ads7846_probe(struct spi_device *spi)
+#ifdef CONFIG_OF
+static const struct of_device_id ads7846_dt_ids[] = {
+	{ .compatible = "ti,tsc2046",	.data = (void *) 7846 },
+	{ .compatible = "ti,ads7843",	.data = (void *) 7843 },
+	{ .compatible = "ti,ads7845",	.data = (void *) 7845 },
+	{ .compatible = "ti,ads7846",	.data = (void *) 7846 },
+	{ .compatible = "ti,ads7873",	.data = (void *) 7873 },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ads7846_dt_ids);
+
+static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+{
+	struct ads7846_platform_data *pdata;
+	struct device_node *node = dev->of_node;
+	const struct of_device_id *match;
+
+	if (!node) {
+		dev_err(dev, "Device does not have associated DT data\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	match = of_match_device(ads7846_dt_ids, dev);
+	if (!match) {
+		dev_err(dev, "Unknown device model\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return ERR_PTR(-ENOMEM);
+
+	pdata->model = (unsigned long)match->data;
+
+	of_property_read_u16(node, "ti,vref-delay-usecs",
+			     &pdata->vref_delay_usecs);
+	of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv);
+	pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on");
+
+	pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy");
+
+	of_property_read_u16(node, "ti,settle-delay-usec",
+			     &pdata->settle_delay_usecs);
+	of_property_read_u16(node, "ti,penirq-recheck-delay-usecs",
+			     &pdata->penirq_recheck_delay_usecs);
+
+	of_property_read_u16(node, "ti,x-plate-ohms", &pdata->x_plate_ohms);
+	of_property_read_u16(node, "ti,y-plate-ohms", &pdata->y_plate_ohms);
+
+	of_property_read_u16(node, "ti,x-min", &pdata->x_min);
+	of_property_read_u16(node, "ti,y-min", &pdata->y_min);
+	of_property_read_u16(node, "ti,x-max", &pdata->x_max);
+	of_property_read_u16(node, "ti,y-max", &pdata->y_max);
+
+	of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min);
+	of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max);
+
+	of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max);
+	of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol);
+	of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep);
+
+	of_property_read_u32(node, "ti,pendown-gpio-debounce",
+			     &pdata->gpio_pendown_debounce);
+
+	pdata->wakeup = of_property_read_bool(node, "linux,wakeup");
+
+	pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0);
+
+	return pdata;
+}
+#else
+static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+{
+	dev_err(dev, "no platform data defined\n");
+	return ERR_PTR(-EINVAL);
+}
+#endif
+
+static int ads7846_probe(struct spi_device *spi)
 {
+	const struct ads7846_platform_data *pdata;
 	struct ads7846 *ts;
 	struct ads7846_packet *packet;
 	struct input_dev *input_dev;
-	struct ads7846_platform_data *pdata = spi->dev.platform_data;
 	unsigned long irq_flags;
 	int err;
 
 	if (!spi->irq) {
 		dev_dbg(&spi->dev, "no IRQ?\n");
-		return -ENODEV;
-	}
-
-	if (!pdata) {
-		dev_dbg(&spi->dev, "no platform data?\n");
-		return -ENODEV;
+		return -EINVAL;
 	}
 
 	/* don't exceed max specified sample rate */
 	if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
-		dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
+		dev_err(&spi->dev, "f(sample) %d KHz?\n",
 				(spi->max_speed_hz/SAMPLE_BITS)/1000);
 		return -EINVAL;
 	}
 
-	/* We'd set TX word size 8 bits and RX word size to 13 bits ... except
+	/*
+	 * We'd set TX word size 8 bits and RX word size to 13 bits ... except
 	 * that even if the hardware can do that, the SPI controller driver
 	 * may not.  So we stick to very-portable 8 bit words, both RX and TX.
 	 */
@@ -1214,22 +1290,30 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 		goto err_free_mem;
 	}
 
-	dev_set_drvdata(&spi->dev, ts);
+	spi_set_drvdata(spi, ts);
 
 	ts->packet = packet;
 	ts->spi = spi;
 	ts->input = input_dev;
-	ts->vref_mv = pdata->vref_mv;
-	ts->swap_xy = pdata->swap_xy;
 
 	mutex_init(&ts->lock);
 	init_waitqueue_head(&ts->wait);
 
+	pdata = dev_get_platdata(&spi->dev);
+	if (!pdata) {
+		pdata = ads7846_probe_dt(&spi->dev);
+		if (IS_ERR(pdata))
+			return PTR_ERR(pdata);
+	}
+
 	ts->model = pdata->model ? : 7846;
 	ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
 	ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
 	ts->pressure_max = pdata->pressure_max ? : ~0;
 
+	ts->vref_mv = pdata->vref_mv;
+	ts->swap_xy = pdata->swap_xy;
+
 	if (pdata->filter != NULL) {
 		if (pdata->filter_init != NULL) {
 			err = pdata->filter_init(pdata, &ts->filter_data);
@@ -1250,7 +1334,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 		ts->filter = ads7846_no_filter;
 	}
 
-	err = ads7846_setup_pendown(spi, ts);
+	err = ads7846_setup_pendown(spi, ts, pdata);
 	if (err)
 		goto err_cleanup_filter;
 
@@ -1327,8 +1411,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 	if (ts->model == 7845)
 		ads7845_read12_ser(&spi->dev, PWRDOWN);
 	else
-		(void) ads7846_read12_ser(&spi->dev,
-				READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON);
+		(void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux));
 
 	err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group);
 	if (err)
@@ -1340,6 +1423,13 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 
 	device_init_wakeup(&spi->dev, pdata->wakeup);
 
+	/*
+	 * If device does not carry platform data we must have allocated it
+	 * when parsing DT data.
+	 */
+	if (!dev_get_platdata(&spi->dev))
+		devm_kfree(&spi->dev, (void *)pdata);
+
 	return 0;
 
  err_remove_attr_group:
@@ -1353,7 +1443,7 @@ static int __devinit ads7846_probe(struct spi_device *spi)
  err_put_regulator:
 	regulator_put(ts->reg);
  err_free_gpio:
-	if (ts->gpio_pendown != -1)
+	if (!ts->get_pendown_state)
 		gpio_free(ts->gpio_pendown);
  err_cleanup_filter:
 	if (ts->filter_cleanup)
@@ -1365,9 +1455,9 @@ static int __devinit ads7846_probe(struct spi_device *spi)
 	return err;
 }
 
-static int __devexit ads7846_remove(struct spi_device *spi)
+static int ads7846_remove(struct spi_device *spi)
 {
-	struct ads7846 *ts = dev_get_drvdata(&spi->dev);
+	struct ads7846 *ts = spi_get_drvdata(spi);
 
 	device_init_wakeup(&spi->dev, false);
 
@@ -1383,8 +1473,13 @@ static int __devexit ads7846_remove(struct spi_device *spi)
 	regulator_disable(ts->reg);
 	regulator_put(ts->reg);
 
-	if (ts->gpio_pendown != -1)
+	if (!ts->get_pendown_state) {
+		/*
+		 * If we are not using specialized pendown method we must
+		 * have been relying on gpio we set up ourselves.
+		 */
 		gpio_free(ts->gpio_pendown);
+	}
 
 	if (ts->filter_cleanup)
 		ts->filter_cleanup(ts->filter_data);
@@ -1400,26 +1495,15 @@ static int __devexit ads7846_remove(struct spi_device *spi)
 static struct spi_driver ads7846_driver = {
 	.driver = {
 		.name	= "ads7846",
-		.bus	= &spi_bus_type,
 		.owner	= THIS_MODULE,
+		.pm	= &ads7846_pm,
+		.of_match_table = of_match_ptr(ads7846_dt_ids),
 	},
 	.probe		= ads7846_probe,
-	.remove		= __devexit_p(ads7846_remove),
-	.suspend	= ads7846_suspend,
-	.resume		= ads7846_resume,
+	.remove		= ads7846_remove,
 };
 
-static int __init ads7846_init(void)
-{
-	return spi_register_driver(&ads7846_driver);
-}
-module_init(ads7846_init);
-
-static void __exit ads7846_exit(void)
-{
-	spi_unregister_driver(&ads7846_driver);
-}
-module_exit(ads7846_exit);
+module_spi_driver(ads7846_driver);
 
 MODULE_DESCRIPTION("ADS7846 TouchScreen Driver");
 MODULE_LICENSE("GPL");