Input: ads7846 - Convert to use software nodes

The Nokia 770 is using GPIOs from the global numberspace on the
CBUS node to pass down to the LCD controller. This regresses when we
let the OMAP GPIO driver use dynamic GPIO base.

The Nokia 770 now has dynamic allocation of IRQ numbers, so this
needs to be fixed for it to work.

As this is the only user of LCD MIPID we can easily augment the
driver to use a GPIO descriptor instead and resolve the issue.

The platform data .shutdown() callback wasn't even used in the
code, but we encode a shutdown asserting RESET in the remove()
callback for completeness sake.

The CBUS also has the ADS7846 touchscreen attached.

Populate the devices on the Nokia 770 CBUS I2C using software
nodes instead of platform data quirks. This includes the LCD
and the ADS7846 touchscreen so the conversion just brings the LCD
along with it as software nodes is an all-or-nothing design
pattern.

The ADS7846 has some limited support for using GPIO descriptors,
let's convert it over completely to using device properties and then
fix all remaining boardfile users to provide all platform data using
software nodes.

Dump the of includes and of_match_ptr() in the ADS7846 driver as part
of the job.

Since we have to move ADS7846 over to obtaining the GPIOs it is
using exclusively from descriptors, we provide descriptor tables
for the two remaining in-kernel boardfiles using ADS7846:

- PXA Spitz
- MIPS Alchemy DB1000 development board

It was too hard for me to include software node conversion of
these two remaining users at this time: the spitz is using a
hscync callback in the platform data that would require further
GPIO descriptor conversion of the Spitz, and moving the hsync
callback down into the driver: it will just become too big of
a job, but it can be done separately.

The MIPS Alchemy DB1000 is simply something I cannot test, so take
the easier approach of just providing some GPIO descriptors in
this case as I don't want the patch to grow too intrusive.

As we see that several device trees have incorrect polarity flags
and just expect to bypass the gpiolib polarity handling, fix up
all device trees too, in a separate patch.

Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Fixes: 92bf78b33b0b ("gpio: omap: use dynamic allocation of base")
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 41 insertions, 72 deletions

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index bb1058b1e7fd..40eb27f1b23f 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -24,11 +24,8 @@
 #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/property.h>
 #include <linux/gpio/consumer.h>
-#include <linux/gpio.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/ads7846.h>
 #include <linux/regulator/consumer.h>
@@ -140,7 +137,7 @@ struct ads7846 {
 	int			(*filter)(void *data, int data_idx, int *val);
 	void			*filter_data;
 	int			(*get_pendown_state)(void);
-	int			gpio_pendown;
+	struct gpio_desc	*gpio_pendown;
 
 	void			(*wait_for_sync)(void);
 };
@@ -223,7 +220,7 @@ static int get_pendown_state(struct ads7846 *ts)
 	if (ts->get_pendown_state)
 		return ts->get_pendown_state();
 
-	return !gpio_get_value(ts->gpio_pendown);
+	return gpiod_get_value(ts->gpio_pendown);
 }
 
 static void ads7846_report_pen_up(struct ads7846 *ts)
@@ -989,8 +986,6 @@ static int ads7846_setup_pendown(struct spi_device *spi,
 				 struct ads7846 *ts,
 				 const struct ads7846_platform_data *pdata)
 {
-	int err;
-
 	/*
 	 * 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
@@ -999,25 +994,15 @@ static int ads7846_setup_pendown(struct spi_device *spi,
 
 	if (pdata->get_pendown_state) {
 		ts->get_pendown_state = pdata->get_pendown_state;
-	} else if (gpio_is_valid(pdata->gpio_pendown)) {
-
-		err = devm_gpio_request_one(&spi->dev, 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;
+	} else {
+		ts->gpio_pendown = gpiod_get(&spi->dev, "pendown", GPIOD_IN);
+		if (IS_ERR(ts->gpio_pendown)) {
+			dev_err(&spi->dev, "failed to request pendown GPIO\n");
+			return PTR_ERR(ts->gpio_pendown);
 		}
-
-		ts->gpio_pendown = pdata->gpio_pendown;
-
 		if (pdata->gpio_pendown_debounce)
-			gpiod_set_debounce(gpio_to_desc(ts->gpio_pendown),
+			gpiod_set_debounce(ts->gpio_pendown,
 					   pdata->gpio_pendown_debounce);
-	} else {
-		dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
-		return -EINVAL;
 	}
 
 	return 0;
@@ -1119,7 +1104,6 @@ static int ads7846_setup_spi_msg(struct ads7846 *ts,
 	return 0;
 }
 
-#ifdef CONFIG_OF
 static const struct of_device_id ads7846_dt_ids[] = {
 	{ .compatible = "ti,tsc2046",	.data = (void *) 7846 },
 	{ .compatible = "ti,ads7843",	.data = (void *) 7843 },
@@ -1130,20 +1114,14 @@ static const struct of_device_id ads7846_dt_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, ads7846_dt_ids);
 
-static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
+static const struct ads7846_platform_data *ads7846_get_props(struct device *dev)
 {
 	struct ads7846_platform_data *pdata;
-	struct device_node *node = dev->of_node;
-	const struct of_device_id *match;
+	const struct platform_device_id *pdev_id;
 	u32 value;
 
-	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) {
+	pdev_id = device_get_match_data(dev);
+	if (!pdev_id) {
 		dev_err(dev, "Unknown device model\n");
 		return ERR_PTR(-EINVAL);
 	}
@@ -1152,60 +1130,51 @@ static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
 	if (!pdata)
 		return ERR_PTR(-ENOMEM);
 
-	pdata->model = (unsigned long)match->data;
+	pdata->model = (unsigned long)pdev_id->driver_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");
+	device_property_read_u16(dev, "ti,vref-delay-usecs",
+				 &pdata->vref_delay_usecs);
+	device_property_read_u16(dev, "ti,vref-mv", &pdata->vref_mv);
+	pdata->keep_vref_on = device_property_read_bool(dev, "ti,keep-vref-on");
 
-	pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy");
+	pdata->swap_xy = device_property_read_bool(dev, "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);
+	device_property_read_u16(dev, "ti,settle-delay-usec",
+				 &pdata->settle_delay_usecs);
+	device_property_read_u16(dev, "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);
+	device_property_read_u16(dev, "ti,x-plate-ohms", &pdata->x_plate_ohms);
+	device_property_read_u16(dev, "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);
+	device_property_read_u16(dev, "ti,x-min", &pdata->x_min);
+	device_property_read_u16(dev, "ti,y-min", &pdata->y_min);
+	device_property_read_u16(dev, "ti,x-max", &pdata->x_max);
+	device_property_read_u16(dev, "ti,y-max", &pdata->y_max);
 
 	/*
 	 * touchscreen-max-pressure gets parsed during
 	 * touchscreen_parse_properties()
 	 */
-	of_property_read_u16(node, "ti,pressure-min", &pdata->pressure_min);
-	if (!of_property_read_u32(node, "touchscreen-min-pressure", &value))
+	device_property_read_u16(dev, "ti,pressure-min", &pdata->pressure_min);
+	if (!device_property_read_u32(dev, "touchscreen-min-pressure", &value))
 		pdata->pressure_min = (u16) value;
-	of_property_read_u16(node, "ti,pressure-max", &pdata->pressure_max);
+	device_property_read_u16(dev, "ti,pressure-max", &pdata->pressure_max);
 
-	of_property_read_u16(node, "ti,debounce-max", &pdata->debounce_max);
-	if (!of_property_read_u32(node, "touchscreen-average-samples", &value))
+	device_property_read_u16(dev, "ti,debounce-max", &pdata->debounce_max);
+	if (!device_property_read_u32(dev, "touchscreen-average-samples", &value))
 		pdata->debounce_max = (u16) value;
-	of_property_read_u16(node, "ti,debounce-tol", &pdata->debounce_tol);
-	of_property_read_u16(node, "ti,debounce-rep", &pdata->debounce_rep);
+	device_property_read_u16(dev, "ti,debounce-tol", &pdata->debounce_tol);
+	device_property_read_u16(dev, "ti,debounce-rep", &pdata->debounce_rep);
 
-	of_property_read_u32(node, "ti,pendown-gpio-debounce",
+	device_property_read_u32(dev, "ti,pendown-gpio-debounce",
 			     &pdata->gpio_pendown_debounce);
 
-	pdata->wakeup = of_property_read_bool(node, "wakeup-source") ||
-			of_property_read_bool(node, "linux,wakeup");
-
-	pdata->gpio_pendown = of_get_named_gpio(dev->of_node, "pendown-gpio", 0);
+	pdata->wakeup = device_property_read_bool(dev, "wakeup-source") ||
+			device_property_read_bool(dev, "linux,wakeup");
 
 	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 void ads7846_regulator_disable(void *regulator)
 {
@@ -1269,7 +1238,7 @@ static int ads7846_probe(struct spi_device *spi)
 
 	pdata = dev_get_platdata(dev);
 	if (!pdata) {
-		pdata = ads7846_probe_dt(dev);
+		pdata = ads7846_get_props(dev);
 		if (IS_ERR(pdata))
 			return PTR_ERR(pdata);
 	}
@@ -1426,7 +1395,7 @@ static struct spi_driver ads7846_driver = {
 	.driver = {
 		.name	= "ads7846",
 		.pm	= pm_sleep_ptr(&ads7846_pm),
-		.of_match_table = of_match_ptr(ads7846_dt_ids),
+		.of_match_table = ads7846_dt_ids,
 	},
 	.probe		= ads7846_probe,
 	.remove		= ads7846_remove,