diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 79 |
1 files changed, 62 insertions, 17 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 844198cb4e31..6367646dce83 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, }; /* @@ -365,22 +367,18 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc) * * Looks for device property "gpio-line-names" and if it exists assigns * GPIO line names for the chip. The memory allocated for the assigned - * names belong to the underlying software node and should not be released + * names belong to the underlying firmware node and should not be released * by the caller. */ static int devprop_gpiochip_set_names(struct gpio_chip *chip) { struct gpio_device *gdev = chip->gpiodev; - struct device *dev = chip->parent; + struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); const char **names; int ret, i; int count; - /* GPIO chip may not have a parent device whose properties we inspect. */ - if (!dev) - return 0; - - count = device_property_string_array_count(dev, "gpio-line-names"); + count = fwnode_property_string_array_count(fwnode, "gpio-line-names"); if (count < 0) return 0; @@ -394,7 +392,7 @@ static int devprop_gpiochip_set_names(struct gpio_chip *chip) if (!names) return -ENOMEM; - ret = device_property_read_string_array(dev, "gpio-line-names", + ret = fwnode_property_read_string_array(fwnode, "gpio-line-names", names, count); if (ret < 0) { dev_warn(&gdev->dev, "failed to read GPIO line names\n"); @@ -472,9 +470,13 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); static void gpiodevice_release(struct device *dev) { - struct gpio_device *gdev = dev_get_drvdata(dev); + struct gpio_device *gdev = container_of(dev, struct gpio_device, dev); + unsigned long flags; + spin_lock_irqsave(&gpio_lock, flags); list_del(&gdev->list); + spin_unlock_irqrestore(&gpio_lock, flags); + ida_free(&gpio_ida, gdev->id); kfree_const(gdev->label); kfree(gdev->descs); @@ -569,6 +571,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, struct lock_class_key *lock_key, struct lock_class_key *request_key) { + struct fwnode_handle *fwnode = gc->parent ? dev_fwnode(gc->parent) : NULL; unsigned long flags; int ret = 0; unsigned i; @@ -590,13 +593,13 @@ 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); + + /* + * Assign fwnode depending on the result of the previous calls, + * if none of them succeed, assign it to the parent's one. + */ + gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode; gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL); if (gdev->id < 0) { @@ -609,7 +612,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, goto err_free_ida; device_initialize(&gdev->dev); - dev_set_drvdata(&gdev->dev, gdev); if (gc->parent && gc->parent->driver) gdev->owner = gc->parent->driver->owner; else if (gc->owner) @@ -4215,6 +4217,41 @@ 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; @@ -4226,9 +4263,17 @@ static int __init gpiolib_dev_init(void) return ret; } + ret = driver_register(&gpio_stub_drv); + if (ret < 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; } |