[PATCH v2 0/3] gpiolib: generalize GPIO line names property

[PATCH v2 0/3] gpiolib: generalize GPIO line names property

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

I initially sent this as part of the gpio-mockup overhaul but since
these patches are indepentent and the work on gpio-mockup may become
more complicated - I'm sending these separately.

The only change is adding additional property helpers to count strings
in array.

v1 -> v2:
- actually remove the previous devprop source file in patch 3
- rename the string counting functions to something more explicit

Bartosz Golaszewski (3):
  device: property: add helpers to count items in string arrays
  gpiolib: generalize devprop_gpiochip_set_names() for device properties
  gpiolib: unexport devprop_gpiochip_set_names()

 drivers/gpio/Makefile          |  1 -
 drivers/gpio/gpiolib-acpi.c    |  3 --
 drivers/gpio/gpiolib-devprop.c | 63 ----------------------------------
 drivers/gpio/gpiolib-of.c      |  5 ---
 drivers/gpio/gpiolib.c         | 55 ++++++++++++++++++++++++++---
 include/linux/gpio/driver.h    |  3 --
 include/linux/property.h       | 13 +++++++
 7 files changed, 64 insertions(+), 79 deletions(-)
 delete mode 100644 drivers/gpio/gpiolib-devprop.c

-- 
2.26.1

[PATCH v2 1/3] device: property: add helpers to count items in string arrays

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Instead of doing the following:

    count = device_property_read_string_array(dev, propname, NULL, 0);

Let's provide inline helpers with hardcoded arguments for counting
strings in property arrays.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 include/linux/property.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/linux/property.h b/include/linux/property.h
index 9f805c442819..75c178055bc9 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -170,6 +170,12 @@ static inline int device_property_count_u64(struct device *dev, const char *prop
 	return device_property_read_u64_array(dev, propname, NULL, 0);
 }
 
+static inline int device_property_string_array_count(struct device *dev,
+						     const char *propname)
+{
+	return device_property_read_string_array(dev, propname, NULL, 0);
+}
+
 static inline bool fwnode_property_read_bool(const struct fwnode_handle *fwnode,
 					     const char *propname)
 {
@@ -224,6 +230,13 @@ static inline int fwnode_property_count_u64(const struct fwnode_handle *fwnode,
 	return fwnode_property_read_u64_array(fwnode, propname, NULL, 0);
 }
 
+static inline int
+fwnode_property_string_array_count(const struct fwnode_handle *fwnode,
+				   const char *propname)
+{
+	return fwnode_property_read_string_array(fwnode, propname, NULL, 0);
+}
+
 struct software_node;
 
 /**
-- 
2.26.1

[PATCH v2 2/3] gpiolib: generalize devprop_gpiochip_set_names() for device properties

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

devprop_gpiochip_set_names() is overly complicated with taking the
fwnode argument (which requires using dev_fwnode() & of_fwnode_handle()
in ACPI and OF GPIO code respectively). Let's just switch to using the
generic device properties.

This allows us to pull the code setting line names directly into
gpiochip_add_data_with_key() instead of handling it separately for
ACPI and OF.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/gpio/gpiolib-acpi.c    |  3 ---
 drivers/gpio/gpiolib-devprop.c | 20 ++++++++++----------
 drivers/gpio/gpiolib-of.c      |  5 -----
 drivers/gpio/gpiolib.c         |  8 ++++----
 include/linux/gpio/driver.h    |  3 +--
 5 files changed, 15 insertions(+), 24 deletions(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 54ca3c18b291..834a12f3219e 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -1221,9 +1221,6 @@ void acpi_gpiochip_add(struct gpio_chip *chip)
 		return;
 	}
 
-	if (!chip->names)
-		devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent));
-
 	acpi_gpiochip_request_regions(acpi_gpio);
 	acpi_gpiochip_scan_gpios(acpi_gpio);
 	acpi_walk_dep_device_list(handle);
diff --git a/drivers/gpio/gpiolib-devprop.c b/drivers/gpio/gpiolib-devprop.c
index 26741032fa9e..31599d89a85d 100644
--- a/drivers/gpio/gpiolib-devprop.c
+++ b/drivers/gpio/gpiolib-devprop.c
@@ -17,25 +17,23 @@
 /**
  * devprop_gpiochip_set_names - Set GPIO line names using device properties
  * @chip: GPIO chip whose lines should be named, if possible
- * @fwnode: Property Node containing the gpio-line-names property
  *
  * Looks for device property "gpio-line-names" and if it exists assigns
  * GPIO line names for the chip. The memory allocated for the assigned
- * names belong to the underlying firmware node and should not be released
+ * names belong to the underlying software node and should not be released
  * by the caller.
  */
-void devprop_gpiochip_set_names(struct gpio_chip *chip,
-				const struct fwnode_handle *fwnode)
+int devprop_gpiochip_set_names(struct gpio_chip *chip)
 {
 	struct gpio_device *gdev = chip->gpiodev;
+	struct device *dev = chip->parent;
 	const char **names;
 	int ret, i;
 	int count;
 
-	count = fwnode_property_read_string_array(fwnode, "gpio-line-names",
-						  NULL, 0);
+	count = device_property_string_array_count(dev, "gpio-line-names");
 	if (count < 0)
-		return;
+		return 0;
 
 	if (count > gdev->ngpio) {
 		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
@@ -45,19 +43,21 @@ void devprop_gpiochip_set_names(struct gpio_chip *chip,
 
 	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
 	if (!names)
-		return;
+		return -ENOMEM;
 
-	ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
+	ret = device_property_read_string_array(dev, "gpio-line-names",
 						names, count);
 	if (ret < 0) {
 		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
 		kfree(names);
-		return;
+		return ret;
 	}
 
 	for (i = 0; i < count; i++)
 		gdev->descs[i].name = names[i];
 
 	kfree(names);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names);
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index bd31dd3b6a75..2f895a2b8411 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -1026,11 +1026,6 @@ int of_gpiochip_add(struct gpio_chip *chip)
 	if (ret)
 		return ret;
 
-	/* If the chip defines names itself, these take precedence */
-	if (!chip->names)
-		devprop_gpiochip_set_names(chip,
-					   of_fwnode_handle(chip->of_node));
-
 	of_node_get(chip->of_node);
 
 	ret = of_gpiochip_scan_gpios(chip);
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 80137c1b3cdc..0d390f0ec32c 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -340,9 +340,6 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc)
 	struct gpio_device *gdev = gc->gpiodev;
 	int i;
 
-	if (!gc->names)
-		return 0;
-
 	/* First check all names if they are unique */
 	for (i = 0; i != gc->ngpio; ++i) {
 		struct gpio_desc *gpio;
@@ -621,7 +618,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 	INIT_LIST_HEAD(&gdev->pin_ranges);
 #endif
 
-	ret = gpiochip_set_desc_names(gc);
+	if (gc->names)
+		ret = gpiochip_set_desc_names(gc);
+	else
+		ret = devprop_gpiochip_set_names(gc);
 	if (ret)
 		goto err_remove_from_list;
 
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index d1cef5c2715c..56485a040b82 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -756,8 +756,7 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
 					    enum gpiod_flags dflags);
 void gpiochip_free_own_desc(struct gpio_desc *desc);
 
-void devprop_gpiochip_set_names(struct gpio_chip *gc,
-				const struct fwnode_handle *fwnode);
+int devprop_gpiochip_set_names(struct gpio_chip *gc);
 
 #ifdef CONFIG_GPIOLIB
 
-- 
2.26.1

[PATCH v2 3/3] gpiolib: unexport devprop_gpiochip_set_names()

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Now that devprop_gpiochip_set_names() is only used in a single place
inside drivers/gpio/gpiolib.c, there's no need anymore for it to be
exported or to even live in its own source file. Pull this function into
the core source file for gpiolib.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 drivers/gpio/Makefile          |  1 -
 drivers/gpio/gpiolib-devprop.c | 63 ----------------------------------
 drivers/gpio/gpiolib.c         | 47 +++++++++++++++++++++++++
 include/linux/gpio/driver.h    |  2 --
 4 files changed, 47 insertions(+), 66 deletions(-)
 delete mode 100644 drivers/gpio/gpiolib-devprop.c

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 4f9abff4f2dc..639275eb4e4d 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -6,7 +6,6 @@ ccflags-$(CONFIG_DEBUG_GPIO)	+= -DDEBUG
 obj-$(CONFIG_GPIOLIB)		+= gpiolib.o
 obj-$(CONFIG_GPIOLIB)		+= gpiolib-devres.o
 obj-$(CONFIG_GPIOLIB)		+= gpiolib-legacy.o
-obj-$(CONFIG_GPIOLIB)		+= gpiolib-devprop.o
 obj-$(CONFIG_GPIOLIB)		+= gpiolib-cdev.o
 obj-$(CONFIG_OF_GPIO)		+= gpiolib-of.o
 obj-$(CONFIG_GPIO_SYSFS)	+= gpiolib-sysfs.o
diff --git a/drivers/gpio/gpiolib-devprop.c b/drivers/gpio/gpiolib-devprop.c
deleted file mode 100644
index 31599d89a85d..000000000000
--- a/drivers/gpio/gpiolib-devprop.c
+++ /dev/null
@@ -1,63 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Device property helpers for GPIO chips.
- *
- * Copyright (C) 2016, Intel Corporation
- * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
- */
-
-#include <linux/property.h>
-#include <linux/slab.h>
-#include <linux/gpio/consumer.h>
-#include <linux/gpio/driver.h>
-#include <linux/export.h>
-
-#include "gpiolib.h"
-
-/**
- * devprop_gpiochip_set_names - Set GPIO line names using device properties
- * @chip: GPIO chip whose lines should be named, if possible
- *
- * Looks for device property "gpio-line-names" and if it exists assigns
- * GPIO line names for the chip. The memory allocated for the assigned
- * names belong to the underlying software node and should not be released
- * by the caller.
- */
-int devprop_gpiochip_set_names(struct gpio_chip *chip)
-{
-	struct gpio_device *gdev = chip->gpiodev;
-	struct device *dev = chip->parent;
-	const char **names;
-	int ret, i;
-	int count;
-
-	count = device_property_string_array_count(dev, "gpio-line-names");
-	if (count < 0)
-		return 0;
-
-	if (count > gdev->ngpio) {
-		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
-			 count, gdev->ngpio);
-		count = gdev->ngpio;
-	}
-
-	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
-	if (!names)
-		return -ENOMEM;
-
-	ret = device_property_read_string_array(dev, "gpio-line-names",
-						names, count);
-	if (ret < 0) {
-		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
-		kfree(names);
-		return ret;
-	}
-
-	for (i = 0; i < count; i++)
-		gdev->descs[i].name = names[i];
-
-	kfree(names);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names);
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 0d390f0ec32c..943a2de340d8 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -358,6 +358,53 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc)
 	return 0;
 }
 
+/*
+ * devprop_gpiochip_set_names - Set GPIO line names using device properties
+ * @chip: GPIO chip whose lines should be named, if possible
+ *
+ * Looks for device property "gpio-line-names" and if it exists assigns
+ * GPIO line names for the chip. The memory allocated for the assigned
+ * names belong to the underlying software node and should not be released
+ * by the caller.
+ */
+static int devprop_gpiochip_set_names(struct gpio_chip *chip)
+{
+	struct gpio_device *gdev = chip->gpiodev;
+	struct device *dev = chip->parent;
+	const char **names;
+	int ret, i;
+	int count;
+
+	count = device_property_string_array_count(dev, "gpio-line-names");
+	if (count < 0)
+		return 0;
+
+	if (count > gdev->ngpio) {
+		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
+			 count, gdev->ngpio);
+		count = gdev->ngpio;
+	}
+
+	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
+	if (!names)
+		return -ENOMEM;
+
+	ret = device_property_read_string_array(dev, "gpio-line-names",
+						names, count);
+	if (ret < 0) {
+		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
+		kfree(names);
+		return ret;
+	}
+
+	for (i = 0; i < count; i++)
+		gdev->descs[i].name = names[i];
+
+	kfree(names);
+
+	return 0;
+}
+
 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
 {
 	unsigned long *p;
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 56485a040b82..4a7e295c3640 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -756,8 +756,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc,
 					    enum gpiod_flags dflags);
 void gpiochip_free_own_desc(struct gpio_desc *desc);
 
-int devprop_gpiochip_set_names(struct gpio_chip *gc);
-
 #ifdef CONFIG_GPIOLIB
 
 /* lock/unlock as IRQ */
-- 
2.26.1

Re: [PATCH v2 0/3] gpiolib: generalize GPIO line names property

[Mika Westerberg]

On Wed, Sep 09, 2020 at 10:54:23AM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> 
> I initially sent this as part of the gpio-mockup overhaul but since
> these patches are indepentent and the work on gpio-mockup may become
> more complicated - I'm sending these separately.
> 
> The only change is adding additional property helpers to count strings
> in array.
> 
> v1 -> v2:
> - actually remove the previous devprop source file in patch 3
> - rename the string counting functions to something more explicit
> 
> Bartosz Golaszewski (3):
>   device: property: add helpers to count items in string arrays
>   gpiolib: generalize devprop_gpiochip_set_names() for device properties
>   gpiolib: unexport devprop_gpiochip_set_names()

The series looks good to me,

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Re: [PATCH v2 0/3] gpiolib: generalize GPIO line names property

[Andy Shevchenko]

On Wed, Sep 09, 2020 at 10:54:23AM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> 
> I initially sent this as part of the gpio-mockup overhaul but since
> these patches are indepentent and the work on gpio-mockup may become
> more complicated - I'm sending these separately.
> 
> The only change is adding additional property helpers to count strings
> in array.

Seems it lost my tag for patch 1/3, but in any case now I'm good with it
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> v1 -> v2:
> - actually remove the previous devprop source file in patch 3
> - rename the string counting functions to something more explicit
> 
> Bartosz Golaszewski (3):
>   device: property: add helpers to count items in string arrays
>   gpiolib: generalize devprop_gpiochip_set_names() for device properties
>   gpiolib: unexport devprop_gpiochip_set_names()
> 
>  drivers/gpio/Makefile          |  1 -
>  drivers/gpio/gpiolib-acpi.c    |  3 --
>  drivers/gpio/gpiolib-devprop.c | 63 ----------------------------------
>  drivers/gpio/gpiolib-of.c      |  5 ---
>  drivers/gpio/gpiolib.c         | 55 ++++++++++++++++++++++++++---
>  include/linux/gpio/driver.h    |  3 --
>  include/linux/property.h       | 13 +++++++
>  7 files changed, 64 insertions(+), 79 deletions(-)
>  delete mode 100644 drivers/gpio/gpiolib-devprop.c
> 
> -- 
> 2.26.1
> 

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 0/3] gpiolib: generalize GPIO line names property

[Bartosz Golaszewski]

On Wed, Sep 9, 2020 at 12:34 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Wed, Sep 09, 2020 at 10:54:23AM +0200, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> >
> > I initially sent this as part of the gpio-mockup overhaul but since
> > these patches are indepentent and the work on gpio-mockup may become
> > more complicated - I'm sending these separately.
> >
> > The only change is adding additional property helpers to count strings
> > in array.
>
> Seems it lost my tag for patch 1/3, but in any case now I'm good with it
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>

I removed your tag from patch 1 because I changed the name of the helpers.

Bartosz