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-rw-r--r--drivers/gpio/gpiolib-of.c11
-rw-r--r--drivers/gpio/gpiolib-of.h5
-rw-r--r--drivers/gpio/gpiolib.c38
3 files changed, 47 insertions, 7 deletions
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index b4a71119a4b0..baf0153b7bca 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -1039,3 +1039,14 @@ void of_gpiochip_remove(struct gpio_chip *chip)
{
of_node_put(chip->of_node);
}
+
+void of_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
+{
+ /* If the gpiochip has an assigned OF node this takes precedence */
+ if (gc->of_node)
+ gdev->dev.of_node = gc->of_node;
+ else
+ gc->of_node = gdev->dev.of_node;
+ if (gdev->dev.of_node)
+ gdev->dev.fwnode = of_fwnode_handle(gdev->dev.of_node);
+}
diff --git a/drivers/gpio/gpiolib-of.h b/drivers/gpio/gpiolib-of.h
index ed26664f1537..8af2bc899aab 100644
--- a/drivers/gpio/gpiolib-of.h
+++ b/drivers/gpio/gpiolib-of.h
@@ -15,6 +15,7 @@ int of_gpiochip_add(struct gpio_chip *gc);
void of_gpiochip_remove(struct gpio_chip *gc);
int of_gpio_get_count(struct device *dev, const char *con_id);
bool of_gpio_need_valid_mask(const struct gpio_chip *gc);
+void of_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev);
#else
static inline struct gpio_desc *of_find_gpio(struct device *dev,
const char *con_id,
@@ -33,6 +34,10 @@ static inline bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
{
return false;
}
+static inline void of_gpio_dev_init(struct gpio_chip *gc,
+ struct gpio_device *gdev)
+{
+}
#endif /* CONFIG_OF_GPIO */
extern struct notifier_block gpio_of_notifier;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index b78a634cca24..8e0564c50840 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -590,13 +590,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
gdev->dev.of_node = gc->parent->of_node;
}
-#ifdef CONFIG_OF_GPIO
- /* If the gpiochip has an assigned OF node this takes precedence */
- if (gc->of_node)
- gdev->dev.of_node = gc->of_node;
- else
- gc->of_node = gdev->dev.of_node;
-#endif
+ of_gpio_dev_init(gc, gdev);
gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
if (gdev->id < 0) {
@@ -4205,6 +4199,29 @@ void gpiod_put_array(struct gpio_descs *descs)
}
EXPORT_SYMBOL_GPL(gpiod_put_array);
+static int gpio_stub_drv_probe(struct device *dev)
+{
+ /*
+ * The DT node of some GPIO chips have a "compatible" property, but
+ * never have a struct device added and probed by a driver to register
+ * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause
+ * the consumers of the GPIO chip to get probe deferred forever because
+ * they will be waiting for a device associated with the GPIO chip
+ * firmware node to get added and bound to a driver.
+ *
+ * To allow these consumers to probe, we associate the struct
+ * gpio_device of the GPIO chip with the firmware node and then simply
+ * bind it to this stub driver.
+ */
+ return 0;
+}
+
+static struct device_driver gpio_stub_drv = {
+ .name = "gpio_stub_drv",
+ .bus = &gpio_bus_type,
+ .probe = gpio_stub_drv_probe,
+};
+
static int __init gpiolib_dev_init(void)
{
int ret;
@@ -4216,9 +4233,16 @@ static int __init gpiolib_dev_init(void)
return ret;
}
+ if (driver_register(&gpio_stub_drv) < 0) {
+ pr_err("gpiolib: could not register GPIO stub driver\n");
+ bus_unregister(&gpio_bus_type);
+ return ret;
+ }
+
ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME);
if (ret < 0) {
pr_err("gpiolib: failed to allocate char dev region\n");
+ driver_unregister(&gpio_stub_drv);
bus_unregister(&gpio_bus_type);
return ret;
}