[PATCH 1/3] regulator-core: support multiple enable GPIO

[Kim, Milo]

 This patch fixes a limitation in case of multiple enable pin usages.
 Several regulators can be enabled/disabled at the same time by one
 shared GPIO pin.
 If specific GPIO pin is already used, then skip requesting the GPIO.

Signed-off-by: Milo(Woogyom) Kim <milo....@ti.com>
---
 drivers/regulator/core.c |   21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index de47880..21b4247 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1456,6 +1456,23 @@ void devm_regulator_put(struct regulator *regulator)
 }
 EXPORT_SYMBOL_GPL(devm_regulator_put);
 
+static int regulator_enable_gpio_request(struct regulator_dev *rdev,
+                                       const struct regulator_config *config)
+{
+       struct regulator_dev *r;
+       int gpio = config->ena_gpio;
+
+       list_for_each_entry(r, &regulator_list, list) {
+               if (r->ena_gpio == gpio) {
+                       rdev_info(rdev, "GPIO %d is already used\n", gpio);
+                       return 0;
+               }
+       }
+
+       return gpio_request_one(gpio, GPIOF_DIR_OUT | config->ena_gpio_flags,
+                               rdev_get_name(rdev));
+}
+
 static int _regulator_do_enable(struct regulator_dev *rdev)
 {
        int ret, delay;
@@ -3420,9 +3437,7 @@ regulator_register(const struct regulator_desc 
*regulator_desc,
        dev_set_drvdata(&rdev->dev, rdev);
 
        if (config->ena_gpio && gpio_is_valid(config->ena_gpio)) {
-               ret = gpio_request_one(config->ena_gpio,
-                                      GPIOF_DIR_OUT | config->ena_gpio_flags,
-                                      rdev_get_name(rdev));
+               ret = regulator_enable_gpio_request(rdev, config);
                if (ret != 0) {
                        rdev_err(rdev, "Failed to request enable GPIO%d: %d\n",
                                 config->ena_gpio, ret);
-- 
1.7.9.5


Best Regards,
Milo


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