regulator: gpio: properly check return value of of_get_named_gpio

The function of_get_named_gpio() could return -ENOENT, -EPROBE_DEFER
-EINVAL and so on. Currently, for the optional property "enable-gpio",
we only check -EPROBE_DEFER, this is not enough since there may be
misconfigured "enable-gpio" in the DTB, of_get_named_gpio() will return
-EINVAL in this case, we should return immediately here. And for the
optional property "gpios", we didn't check the return value, the driver
will continue to the point where gpio_request_array() is called, it
doesn't make sense to continue if we got -EPROBE_DEFER or -EINVAL here.

This patch tries to address these two issues by properly checking the
return value of of_get_named_gpio.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/regulator/gpio-regulator.c b/drivers/regulator/gpio-regulator.c
index 83e89e5d4752..0fce06acfaec 100644
--- a/drivers/regulator/gpio-regulator.c
+++ b/drivers/regulator/gpio-regulator.c
@@ -162,8 +162,8 @@ of_get_gpio_regulator_config(struct device *dev, struct device_node *np,
         of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
 
         config->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0);
-        if (config->enable_gpio == -EPROBE_DEFER)
-                return ERR_PTR(-EPROBE_DEFER);
+        if (config->enable_gpio < 0 && config->enable_gpio != -ENOENT)
+                return ERR_PTR(config->enable_gpio);
 
         /* Fetch GPIOs. - optional property*/
         ret = of_gpio_count(np);
@@ -190,8 +190,11 @@ of_get_gpio_regulator_config(struct device *dev, struct device_node *np,
 
                 for (i = 0; i < config->nr_gpios; i++) {
                         gpio = of_get_named_gpio(np, "gpios", i);
-                        if (gpio < 0)
+                        if (gpio < 0) {
+                                if (gpio != -ENOENT)
+                                        return ERR_PTR(gpio);
                                 break;
+                        }
                         config->gpios[i].gpio = gpio;
                         if (proplen > 0) {
                                 of_property_read_u32_index(np, "gpios-states",