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-rw-r--r--drivers/gpio/gpiolib.c19
-rw-r--r--drivers/regulator/fixed.c13
-rw-r--r--include/linux/gpio/consumer.h1
3 files changed, 31 insertions, 2 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e8f8a1999393..8228306aba46 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -3908,8 +3908,23 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
* the device name as label
*/
status = gpiod_request(desc, con_id ? con_id : devname);
- if (status < 0)
- return ERR_PTR(status);
+ if (status < 0) {
+ if (status == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
+ /*
+ * This happens when there are several consumers for
+ * the same GPIO line: we just return here without
+ * further initialization. It is a bit if a hack.
+ * This is necessary to support fixed regulators.
+ *
+ * FIXME: Make this more sane and safe.
+ */
+ dev_info(dev, "nonexclusive access to GPIO for %s\n",
+ con_id ? con_id : devname);
+ return desc;
+ } else {
+ return ERR_PTR(status);
+ }
+ }
status = gpiod_configure_flags(desc, con_id, lookupflags, flags);
if (status < 0) {
diff --git a/drivers/regulator/fixed.c b/drivers/regulator/fixed.c
index 7d639ad953b6..ccc29038f19a 100644
--- a/drivers/regulator/fixed.c
+++ b/drivers/regulator/fixed.c
@@ -170,6 +170,19 @@ static int reg_fixed_voltage_probe(struct platform_device *pdev)
gflags = GPIOD_OUT_LOW_OPEN_DRAIN;
}
+ /*
+ * Some fixed regulators share the enable line between two
+ * regulators which makes it necessary to get a handle on the
+ * same descriptor for two different consumers. This will get
+ * the GPIO descriptor, but only the first call will initialize
+ * it so any flags such as inversion or open drain will only
+ * be set up by the first caller and assumed identical on the
+ * next caller.
+ *
+ * FIXME: find a better way to deal with this.
+ */
+ gflags |= GPIOD_FLAGS_BIT_NONEXCLUSIVE;
+
cfg.ena_gpiod = devm_gpiod_get_optional(&pdev->dev, NULL, gflags);
if (IS_ERR(cfg.ena_gpiod))
return PTR_ERR(cfg.ena_gpiod);
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index 21ddbe440030..33695a1d8b35 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -30,6 +30,7 @@ struct gpio_descs {
#define GPIOD_FLAGS_BIT_DIR_OUT BIT(1)
#define GPIOD_FLAGS_BIT_DIR_VAL BIT(2)
#define GPIOD_FLAGS_BIT_OPEN_DRAIN BIT(3)
+#define GPIOD_FLAGS_BIT_NONEXCLUSIVE BIT(4)
/**
* Optional flags that can be passed to one of gpiod_* to configure direction