gpiolib: Introduce for_each_gpio_property_name() helper

Introduce a helper macro for_each_gpio_property_name().
With that in place, update users. This, in particular,
will help making the following simplifications easier.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240819142945.327808-2-andriy.shevchenko@linux.intel.comSigned-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpiolib-acpi.c

@@ -973,18 +973,9 @@ __acpi_find_gpio(struct fwnode_handle *fwnode, const char *con_id, unsigned int
 	struct acpi_device *adev = to_acpi_device_node(fwnode);
 	struct gpio_desc *desc;
 	char propname[32];
-	int i;
 
 	/* Try first from _DSD */
-	for (i = 0; i < gpio_suffix_count; i++) {
-		if (con_id) {
-			snprintf(propname, sizeof(propname), "%s-%s",
-				 con_id, gpio_suffixes[i]);
-		} else {
-			snprintf(propname, sizeof(propname), "%s",
-				 gpio_suffixes[i]);
-		}
-
+	for_each_gpio_property_name(propname, con_id) {
 		if (adev)
 			desc = acpi_get_gpiod_by_index(adev,
 						       propname, idx, info);
@@ -1450,17 +1441,9 @@ int acpi_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)
 	int count = -ENOENT;
 	int ret;
 	char propname[32];
-	unsigned int i;
 
 	/* Try first from _DSD */
-	for (i = 0; i < gpio_suffix_count; i++) {
-		if (con_id)
-			snprintf(propname, sizeof(propname), "%s-%s",
-				 con_id, gpio_suffixes[i]);
-		else
-			snprintf(propname, sizeof(propname), "%s",
-				 gpio_suffixes[i]);
-
+	for_each_gpio_property_name(propname, con_id) {
 		ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY, &obj);
 		if (ret == 0) {
 			if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)

drivers/gpio/gpiolib-of.c

@@ -97,20 +97,12 @@ int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)
 	const struct device_node *np = to_of_node(fwnode);
 	int ret;
 	char propname[32];
-	unsigned int i;
 
 	ret = of_gpio_spi_cs_get_count(np, con_id);
 	if (ret > 0)
 		return ret;
 
-	for (i = 0; i < gpio_suffix_count; i++) {
-		if (con_id)
-			snprintf(propname, sizeof(propname), "%s-%s",
-				 con_id, gpio_suffixes[i]);
-		else
-			snprintf(propname, sizeof(propname), "%s",
-				 gpio_suffixes[i]);
-
+	for_each_gpio_property_name(propname, con_id) {
 		ret = of_gpio_named_count(np, propname);
 		if (ret > 0)
 			break;
@@ -685,23 +677,14 @@ static const of_find_gpio_quirk of_find_gpio_quirks[] = {
 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,
 			       unsigned int idx, unsigned long *flags)
 {
-	char prop_name[32]; /* 32 is max size of property name */
+	char propname[32]; /* 32 is max size of property name */
 	enum of_gpio_flags of_flags;
 	const of_find_gpio_quirk *q;
 	struct gpio_desc *desc;
-	unsigned int i;
 
 	/* Try GPIO property "foo-gpios" and "foo-gpio" */
-	for (i = 0; i < gpio_suffix_count; i++) {
-		if (con_id)
-			snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
-				 gpio_suffixes[i]);
-		else
-			snprintf(prop_name, sizeof(prop_name), "%s",
-				 gpio_suffixes[i]);
-
-		desc = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags);
-
+	for_each_gpio_property_name(propname, con_id) {
+		desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags);
 		if (!gpiod_not_found(desc))
 			break;
 	}

drivers/gpio/gpiolib.h

@@ -93,6 +93,19 @@ static inline struct gpio_device *to_gpio_device(struct device *dev)
 extern const char *const gpio_suffixes[];
 extern const size_t gpio_suffix_count;
 
+#define for_each_gpio_property_name(propname, con_id)					\
+	for (unsigned int __i = 0;							\
+	     __i < gpio_suffix_count && ({						\
+		     const char *__gs = gpio_suffixes[__i];				\
+											\
+		if (con_id)								\
+			snprintf(propname, sizeof(propname), "%s-%s", con_id, __gs);	\
+		else									\
+			snprintf(propname, sizeof(propname), "%s", __gs);		\
+		1;									\
+	     });									\
+	     __i++)
+
 /**
  * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes
  *