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path: root/drivers/gpio/gpiolib.c
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Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c71
1 files changed, 61 insertions, 10 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index b02cc2abd3b6..adf55db080d8 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -56,8 +56,10 @@
static DEFINE_IDA(gpio_ida);
static dev_t gpio_devt;
#define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
+static int gpio_bus_match(struct device *dev, struct device_driver *drv);
static struct bus_type gpio_bus_type = {
.name = "gpio",
+ .match = gpio_bus_match,
};
/*
@@ -590,20 +592,18 @@ 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) {
ret = gdev->id;
goto err_free_gdev;
}
- dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
+
+ ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
+ if (ret)
+ goto err_free_ida;
+
device_initialize(&gdev->dev);
dev_set_drvdata(&gdev->dev, gdev);
if (gc->parent && gc->parent->driver)
@@ -617,7 +617,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
if (!gdev->descs) {
ret = -ENOMEM;
- goto err_free_ida;
+ goto err_free_dev_name;
}
if (gc->ngpio == 0) {
@@ -768,6 +768,8 @@ err_free_label:
kfree_const(gdev->label);
err_free_descs:
kfree(gdev->descs);
+err_free_dev_name:
+ kfree(dev_name(&gdev->dev));
err_free_ida:
ida_free(&gpio_ida, gdev->id);
err_free_gdev:
@@ -1489,6 +1491,9 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc,
type = IRQ_TYPE_NONE;
}
+ if (gc->to_irq)
+ chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__);
+
gc->to_irq = gpiochip_to_irq;
gc->irq.default_type = type;
gc->irq.lock_key = lock_key;
@@ -2548,7 +2553,7 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep,
struct gpio_chip *gc = desc_array[i]->gdev->chip;
unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
unsigned long *mask, *bits;
- int first, j, ret;
+ int first, j;
if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
mask = fastpath;
@@ -3460,6 +3465,10 @@ EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);
*/
void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
{
+ /* Nothing to remove */
+ if (!table)
+ return;
+
mutex_lock(&gpio_lookup_lock);
list_del(&table->list);
@@ -4202,6 +4211,41 @@ void gpiod_put_array(struct gpio_descs *descs)
}
EXPORT_SYMBOL_GPL(gpiod_put_array);
+
+static int gpio_bus_match(struct device *dev, struct device_driver *drv)
+{
+ /*
+ * Only match if the fwnode doesn't already have a proper struct device
+ * created for it.
+ */
+ if (dev->fwnode && dev->fwnode->dev != dev)
+ return 0;
+ return 1;
+}
+
+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;
@@ -4213,9 +4257,16 @@ 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;
}