[PATCH v1 5/5] gpio: regmap: Allow ngpio to be read from the property

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

GPIOLIB supports the case when number of supported GPIOs can be read
from the device property. Enable this for drivers that are using
GPIO regmap layer.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 drivers/gpio/gpio-regmap.c  | 13 +++++++++----
 include/linux/gpio/regmap.h |  2 +-
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
index 41ee576e7cd0..856f8569566e 100644
--- a/drivers/gpio/gpio-regmap.c
+++ b/drivers/gpio/gpio-regmap.c
@@ -17,6 +17,8 @@
 #include <linux/gpio/driver.h>
 #include <linux/gpio/regmap.h>
 
+#include "gpiolib.h"
+
 struct gpio_regmap {
 	struct device *parent;
 	struct regmap *regmap;
@@ -210,9 +212,6 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
 	if (!config->parent)
 		return ERR_PTR(-EINVAL);
 
-	if (!config->ngpio)
-		return ERR_PTR(-EINVAL);
-
 	/* we need at least one */
 	if (!config->reg_dat_base && !config->reg_set_base)
 		return ERR_PTR(-EINVAL);
@@ -243,7 +242,6 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
 	chip->parent = config->parent;
 	chip->fwnode = config->fwnode;
 	chip->base = -1;
-	chip->ngpio = config->ngpio;
 	chip->names = config->names;
 	chip->label = config->label ?: dev_name(config->parent);
 	chip->can_sleep = regmap_might_sleep(config->regmap);
@@ -262,6 +260,13 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
 		chip->direction_output = gpio_regmap_direction_output;
 	}
 
+	chip->ngpio = config->ngpio;
+	if (!chip->ngpio) {
+		ret = gpiochip_get_ngpios(chip, chip->parent);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
 	/* if not set, assume there is only one register */
 	gpio->ngpio_per_reg = config->ngpio_per_reg;
 	if (!gpio->ngpio_per_reg)
diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
index b9240e4156cc..c722c67668c6 100644
--- a/include/linux/gpio/regmap.h
+++ b/include/linux/gpio/regmap.h
@@ -21,7 +21,7 @@ struct regmap;
  *			If not given, the fwnode of the parent is used.
  * @label:		(Optional) Descriptive name for GPIO controller.
  *			If not given, the name of the device is used.
- * @ngpio:		Number of GPIOs
+ * @ngpio:		(Optional) Number of GPIOs
  * @names:		(Optional) Array of names for gpios
  * @reg_dat_base:	(Optional) (in) register base address
  * @reg_set_base:	(Optional) set register base address
-- 
2.45.1.3035.g276e886db78b