[PATCH v2 0/5] Input: gpio_decoder - update driver to use modern APIs

[PATCH v2 0/5] Input: gpio_decoder - update driver to use modern APIs

[Andy Shevchenko]

Update gpio_decoder driver to use modern in-kernel APIs.

Changelog v2:
- fixed typo (LKP), dunno what I have compiled before

v1: 20251112191412.2088105-1-andriy.shevchenko@linux.intel.com

Andy Shevchenko (5):
  Input: gpio_decoder - make use of device properties
  Input: gpio_decoder - unify messages with help of dev_err_probe()
  Input: gpio_decoder - replace custom loop by
    gpiod_get_array_value_cansleep()
  Input: gpio_decoder - make use of the macros from bits.h
  Input: gpio_decoder - don't use "proxy" headers

 drivers/input/misc/gpio_decoder.c | 72 ++++++++++++++-----------------
 1 file changed, 33 insertions(+), 39 deletions(-)

-- 
2.50.1

[PATCH v2 1/5] Input: gpio_decoder - make use of device properties

[Andy Shevchenko]

Convert the module to be property provider agnostic and allow
it to be used on non-OF platforms.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/input/misc/gpio_decoder.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/input/misc/gpio_decoder.c b/drivers/input/misc/gpio_decoder.c
index ee668eba302f..459abc749a49 100644
--- a/drivers/input/misc/gpio_decoder.c
+++ b/drivers/input/misc/gpio_decoder.c
@@ -10,9 +10,10 @@
 #include <linux/gpio/consumer.h>
 #include <linux/input.h>
 #include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
-#include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 
 struct gpio_decoder {
 	struct gpio_descs *input_gpios;
@@ -110,19 +111,17 @@ static int gpio_decoder_probe(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_OF
 static const struct of_device_id gpio_decoder_of_match[] = {
 	{ .compatible = "gpio-decoder", },
-	{ },
+	{ }
 };
 MODULE_DEVICE_TABLE(of, gpio_decoder_of_match);
-#endif
 
 static struct platform_driver gpio_decoder_driver = {
 	.probe		= gpio_decoder_probe,
 	.driver		= {
 		.name	= "gpio-decoder",
-		.of_match_table = of_match_ptr(gpio_decoder_of_match),
+		.of_match_table = gpio_decoder_of_match,
 	}
 };
 module_platform_driver(gpio_decoder_driver);
-- 
2.50.1

[PATCH v2 2/5] Input: gpio_decoder - unify messages with help of dev_err_probe()

[Andy Shevchenko]

Unify error messages that might appear during probe phase by
switching to use dev_err_probe().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/input/misc/gpio_decoder.c | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/input/misc/gpio_decoder.c b/drivers/input/misc/gpio_decoder.c
index 459abc749a49..a2ae400790f9 100644
--- a/drivers/input/misc/gpio_decoder.c
+++ b/drivers/input/misc/gpio_decoder.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/device.h>
+#include <linux/err.h>
 #include <linux/gpio/consumer.h>
 #include <linux/input.h>
 #include <linux/kernel.h>
@@ -73,15 +74,12 @@ static int gpio_decoder_probe(struct platform_device *pdev)
 	device_property_read_u32(dev, "linux,axis", &decoder->axis);
 
 	decoder->input_gpios = devm_gpiod_get_array(dev, NULL, GPIOD_IN);
-	if (IS_ERR(decoder->input_gpios)) {
-		dev_err(dev, "unable to acquire input gpios\n");
-		return PTR_ERR(decoder->input_gpios);
-	}
+	if (IS_ERR(decoder->input_gpios))
+		return dev_err_probe(dev, PTR_ERR(decoder->input_gpios),
+				     "unable to acquire input gpios\n");
 
-	if (decoder->input_gpios->ndescs < 2) {
-		dev_err(dev, "not enough gpios found\n");
-		return -EINVAL;
-	}
+	if (decoder->input_gpios->ndescs < 2)
+		return dev_err_probe(dev, -EINVAL, "not enough gpios found\n");
 
 	if (device_property_read_u32(dev, "decoder-max-value", &max))
 		max = (1U << decoder->input_gpios->ndescs) - 1;
@@ -97,16 +95,12 @@ static int gpio_decoder_probe(struct platform_device *pdev)
 	input_set_abs_params(input, decoder->axis, 0, max, 0, 0);
 
 	err = input_setup_polling(input, gpio_decoder_poll_gpios);
-	if (err) {
-		dev_err(dev, "failed to set up polling\n");
-		return err;
-	}
+	if (err)
+		return dev_err_probe(dev, err, "failed to set up polling\n");
 
 	err = input_register_device(input);
-	if (err) {
-		dev_err(dev, "failed to register input device\n");
-		return err;
-	}
+	if (err)
+		return dev_err_probe(dev, err, "failed to register input device\n");
 
 	return 0;
 }
-- 
2.50.1

[PATCH v2 3/5] Input: gpio_decoder - replace custom loop by gpiod_get_array_value_cansleep()

[Andy Shevchenko]

There is a custom loop that repeats parts of gpiod_get_array_value_cansleep().
Use that in conjunction with bitmap API to make code shorter and easier to
follow.

With this done, add an upper check for amount of GPIOs given based on
the driver's code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/input/misc/gpio_decoder.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/input/misc/gpio_decoder.c b/drivers/input/misc/gpio_decoder.c
index a2ae400790f9..7f319b932550 100644
--- a/drivers/input/misc/gpio_decoder.c
+++ b/drivers/input/misc/gpio_decoder.c
@@ -6,11 +6,13 @@
  * encoded numeric value into an input event.
  */
 
+#include <linux/bitmap.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/gpio/consumer.h>
 #include <linux/input.h>
 #include <linux/kernel.h>
+#include <linux/minmax.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
@@ -26,23 +28,18 @@ struct gpio_decoder {
 static int gpio_decoder_get_gpios_state(struct gpio_decoder *decoder)
 {
 	struct gpio_descs *gpios = decoder->input_gpios;
-	unsigned int ret = 0;
-	int i, val;
+	DECLARE_BITMAP(values, 32);
+	unsigned int size;
+	int err;
 
-	for (i = 0; i < gpios->ndescs; i++) {
-		val = gpiod_get_value_cansleep(gpios->desc[i]);
-		if (val < 0) {
-			dev_err(decoder->dev,
-				"Error reading gpio %d: %d\n",
-				desc_to_gpio(gpios->desc[i]), val);
-			return val;
-		}
-
-		val = !!val;
-		ret = (ret << 1) | val;
+	size = min(gpios->ndescs, 32U);
+	err = gpiod_get_array_value_cansleep(size, gpios->desc, gpios->info, values);
+	if (err) {
+		dev_err(decoder->dev, "Error reading GPIO: %d\n", err);
+		return err;
 	}
 
-	return ret;
+	return bitmap_read(values, 0, size);
 }
 
 static void gpio_decoder_poll_gpios(struct input_dev *input)
@@ -81,6 +78,9 @@ static int gpio_decoder_probe(struct platform_device *pdev)
 	if (decoder->input_gpios->ndescs < 2)
 		return dev_err_probe(dev, -EINVAL, "not enough gpios found\n");
 
+	if (decoder->input_gpios->ndescs > 31)
+		return dev_err_probe(dev, -EINVAL, "too many gpios found\n");
+
 	if (device_property_read_u32(dev, "decoder-max-value", &max))
 		max = (1U << decoder->input_gpios->ndescs) - 1;
 
-- 
2.50.1

[PATCH v2 4/5] Input: gpio_decoder - make use of the macros from bits.h

[Andy Shevchenko]

Make use of BIT() where it makes sense.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/input/misc/gpio_decoder.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/input/misc/gpio_decoder.c b/drivers/input/misc/gpio_decoder.c
index 7f319b932550..057717de9849 100644
--- a/drivers/input/misc/gpio_decoder.c
+++ b/drivers/input/misc/gpio_decoder.c
@@ -60,7 +60,7 @@ static int gpio_decoder_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct gpio_decoder *decoder;
 	struct input_dev *input;
-	u32  max;
+	u32 max;
 	int err;
 
 	decoder = devm_kzalloc(dev, sizeof(*decoder), GFP_KERNEL);
@@ -82,7 +82,7 @@ static int gpio_decoder_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, -EINVAL, "too many gpios found\n");
 
 	if (device_property_read_u32(dev, "decoder-max-value", &max))
-		max = (1U << decoder->input_gpios->ndescs) - 1;
+		max = BIT(decoder->input_gpios->ndescs) - 1;
 
 	input = devm_input_allocate_device(dev);
 	if (!input)
-- 
2.50.1

[PATCH v2 5/5] Input: gpio_decoder - don't use "proxy" headers

[Andy Shevchenko]

Update header inclusions to follow IWYU (Include What You Use)
principle.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/input/misc/gpio_decoder.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/input/misc/gpio_decoder.c b/drivers/input/misc/gpio_decoder.c
index 057717de9849..f0759dd39b35 100644
--- a/drivers/input/misc/gpio_decoder.c
+++ b/drivers/input/misc/gpio_decoder.c
@@ -7,16 +7,17 @@
  */
 
 #include <linux/bitmap.h>
-#include <linux/device.h>
+#include <linux/dev_printk.h>
+#include <linux/device/devres.h>
 #include <linux/err.h>
 #include <linux/gpio/consumer.h>
 #include <linux/input.h>
-#include <linux/kernel.h>
 #include <linux/minmax.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
+#include <linux/types.h>
 
 struct gpio_decoder {
 	struct gpio_descs *input_gpios;
-- 
2.50.1