@@ -4295,6 +4295,50 @@ struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
}
EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
+/**
+ * gpio_property_name_length - Returns the GPIO name length from a property name
+ * @str: string to check
+ *
+ * This function checks if the given name matches the GPIO property patterns, and
+ * returns the length of the name of the GPIO. The pattern is "*-<GPIO suffix>"
+ * or just "<GPIO suffix>".
+ *
+ * Returns:
+ * The length of the string before '-' if it matches "*-<GPIO suffix>", or
+ * 0 if no name part, just the suffix, or
+ * -EINVAL if the string doesn't match the pattern.
+ */
+int gpio_property_name_length(const char *str)
+{
+ size_t len;
+
+ len = strlen(str);
+
+ /* string need to be at minimum len(gpio) */
+ if (len < 4)
+ return -EINVAL;
+
+ /* Check for no-name case: "gpio" / "gpios" */
+ for (const char *const *p = gpio_suffixes; *p; p++)
+ if (!strcmp(str, *p))
+ return 0;
+
+ for (size_t i = len - 4; i > 0; i--) {
+ /* find right-most '-' and check if remainder matches suffix */
+ if (str[i] != '-')
+ continue;
+
+ for (const char *const *p = gpio_suffixes; *p; p++)
+ if (!strcmp(str + i + 1, *p))
+ return i;
+
+ return -EINVAL;
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(gpio_property_name_length);
+
/**
* gpiod_count - return the number of GPIOs associated with a device / function
* or -ENOENT if no GPIO has been assigned to the requested function
@@ -56,6 +56,8 @@ enum gpiod_flags {
#ifdef CONFIG_GPIOLIB
+int gpio_property_name_length(const char *name);
+
/* Return the number of GPIOs associated with a device / function */
int gpiod_count(struct device *dev, const char *con_id);
The I2C device tree component prober needs to get and toggle GPIO lines for the components it intends to probe. These components may not use the same name for their GPIO lines, so the prober must go through the device tree, check each property to see it is a GPIO property, and get the GPIO line. Instead of duplicating the GPIO suffixes, or exporting them to the prober to do pattern matching, simply add and export a new function that does the pattern matching and returns the length of the GPIO name. The caller can then use that to copy out the name if it needs to. Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> --- Changes since v4: - new patch Depends on commit 4b91188dced8 ("gpiolib: Replace gpio_suffix_count with NULL-terminated array"). --- drivers/gpio/gpiolib.c | 44 +++++++++++++++++++++++++++++++++++ include/linux/gpio/consumer.h | 2 ++ 2 files changed, 46 insertions(+)