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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.c133
1 files changed, 91 insertions, 42 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 72065532c1c7..b747c76fd2b1 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -68,6 +68,7 @@ LIST_HEAD(gpio_devices);
static void gpiochip_free_hogs(struct gpio_chip *chip);
static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
+static bool gpiolib_initialized;
static inline void desc_set_label(struct gpio_desc *d, const char *label)
{
@@ -440,9 +441,63 @@ static void gpiodevice_release(struct device *dev)
cdev_del(&gdev->chrdev);
list_del(&gdev->list);
ida_simple_remove(&gpio_ida, gdev->id);
+ kfree(gdev->label);
+ kfree(gdev->descs);
kfree(gdev);
}
+static int gpiochip_setup_dev(struct gpio_device *gdev)
+{
+ int status;
+
+ cdev_init(&gdev->chrdev, &gpio_fileops);
+ gdev->chrdev.owner = THIS_MODULE;
+ gdev->chrdev.kobj.parent = &gdev->dev.kobj;
+ gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
+ status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1);
+ if (status < 0)
+ chip_warn(gdev->chip, "failed to add char device %d:%d\n",
+ MAJOR(gpio_devt), gdev->id);
+ else
+ chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
+ MAJOR(gpio_devt), gdev->id);
+ status = device_add(&gdev->dev);
+ if (status)
+ goto err_remove_chardev;
+
+ status = gpiochip_sysfs_register(gdev);
+ if (status)
+ goto err_remove_device;
+
+ /* From this point, the .release() function cleans up gpio_device */
+ gdev->dev.release = gpiodevice_release;
+ get_device(&gdev->dev);
+ pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
+ __func__, gdev->base, gdev->base + gdev->ngpio - 1,
+ dev_name(&gdev->dev), gdev->chip->label ? : "generic");
+
+ return 0;
+
+err_remove_device:
+ device_del(&gdev->dev);
+err_remove_chardev:
+ cdev_del(&gdev->chrdev);
+ return status;
+}
+
+static void gpiochip_setup_devs(void)
+{
+ struct gpio_device *gdev;
+ int err;
+
+ list_for_each_entry(gdev, &gpio_devices, list) {
+ err = gpiochip_setup_dev(gdev);
+ if (err)
+ pr_err("%s: Failed to initialize gpio device (%d)\n",
+ dev_name(&gdev->dev), err);
+ }
+}
+
/**
* gpiochip_add_data() - register a gpio_chip
* @chip: the chip to register, with chip->base initialized
@@ -457,6 +512,9 @@ static void gpiodevice_release(struct device *dev)
* the gpio framework's arch_initcall(). Otherwise sysfs initialization
* for GPIOs will fail rudely.
*
+ * gpiochip_add_data() must only be called after gpiolib initialization,
+ * ie after core_initcall().
+ *
* If chip->base is negative, this requests dynamic assignment of
* a range of valid GPIOs.
*/
@@ -504,8 +562,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
else
gdev->owner = THIS_MODULE;
- gdev->descs = devm_kcalloc(&gdev->dev, chip->ngpio,
- sizeof(gdev->descs[0]), GFP_KERNEL);
+ gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
if (!gdev->descs) {
status = -ENOMEM;
goto err_free_gdev;
@@ -514,16 +571,16 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
if (chip->ngpio == 0) {
chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
status = -EINVAL;
- goto err_free_gdev;
+ goto err_free_descs;
}
if (chip->label)
- gdev->label = devm_kstrdup(&gdev->dev, chip->label, GFP_KERNEL);
+ gdev->label = kstrdup(chip->label, GFP_KERNEL);
else
- gdev->label = devm_kstrdup(&gdev->dev, "unknown", GFP_KERNEL);
+ gdev->label = kstrdup("unknown", GFP_KERNEL);
if (!gdev->label) {
status = -ENOMEM;
- goto err_free_gdev;
+ goto err_free_descs;
}
gdev->ngpio = chip->ngpio;
@@ -543,7 +600,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
if (base < 0) {
status = base;
spin_unlock_irqrestore(&gpio_lock, flags);
- goto err_free_gdev;
+ goto err_free_label;
}
/*
* TODO: it should not be necessary to reflect the assigned
@@ -558,7 +615,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
status = gpiodev_add_to_list(gdev);
if (status) {
spin_unlock_irqrestore(&gpio_lock, flags);
- goto err_free_gdev;
+ goto err_free_label;
}
for (i = 0; i < chip->ngpio; i++) {
@@ -596,39 +653,16 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
* we get a device node entry in sysfs under
* /sys/bus/gpio/devices/gpiochipN/dev that can be used for
* coldplug of device nodes and other udev business.
+ * We can do this only if gpiolib has been initialized.
+ * Otherwise, defer until later.
*/
- cdev_init(&gdev->chrdev, &gpio_fileops);
- gdev->chrdev.owner = THIS_MODULE;
- gdev->chrdev.kobj.parent = &gdev->dev.kobj;
- gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
- status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1);
- if (status < 0)
- chip_warn(chip, "failed to add char device %d:%d\n",
- MAJOR(gpio_devt), gdev->id);
- else
- chip_dbg(chip, "added GPIO chardev (%d:%d)\n",
- MAJOR(gpio_devt), gdev->id);
- status = device_add(&gdev->dev);
- if (status)
- goto err_remove_chardev;
-
- status = gpiochip_sysfs_register(gdev);
- if (status)
- goto err_remove_device;
-
- /* From this point, the .release() function cleans up gpio_device */
- gdev->dev.release = gpiodevice_release;
- get_device(&gdev->dev);
- pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
- __func__, gdev->base, gdev->base + gdev->ngpio - 1,
- dev_name(&gdev->dev), chip->label ? : "generic");
-
+ if (gpiolib_initialized) {
+ status = gpiochip_setup_dev(gdev);
+ if (status)
+ goto err_remove_chip;
+ }
return 0;
-err_remove_device:
- device_del(&gdev->dev);
-err_remove_chardev:
- cdev_del(&gdev->chrdev);
err_remove_chip:
acpi_gpiochip_remove(chip);
gpiochip_free_hogs(chip);
@@ -637,6 +671,10 @@ err_remove_from_list:
spin_lock_irqsave(&gpio_lock, flags);
list_del(&gdev->list);
spin_unlock_irqrestore(&gpio_lock, flags);
+err_free_label:
+ kfree(gdev->label);
+err_free_descs:
+ kfree(gdev->descs);
err_free_gdev:
ida_simple_remove(&gpio_ida, gdev->id);
/* failures here can mean systems won't boot... */
@@ -2231,9 +2269,11 @@ static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
return desc;
}
-static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
+static struct gpio_desc *acpi_find_gpio(struct device *dev,
+ const char *con_id,
unsigned int idx,
- enum gpio_lookup_flags *flags)
+ enum gpiod_flags flags,
+ enum gpio_lookup_flags *lookupflags)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
struct acpi_gpio_info info;
@@ -2264,10 +2304,16 @@ static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
if (IS_ERR(desc))
return desc;
+
+ if ((flags == GPIOD_OUT_LOW || flags == GPIOD_OUT_HIGH) &&
+ info.gpioint) {
+ dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
+ return ERR_PTR(-ENOENT);
+ }
}
if (info.polarity == GPIO_ACTIVE_LOW)
- *flags |= GPIO_ACTIVE_LOW;
+ *lookupflags |= GPIO_ACTIVE_LOW;
return desc;
}
@@ -2530,7 +2576,7 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
desc = of_find_gpio(dev, con_id, idx, &lookupflags);
} else if (ACPI_COMPANION(dev)) {
dev_dbg(dev, "using ACPI for GPIO lookup\n");
- desc = acpi_find_gpio(dev, con_id, idx, &lookupflags);
+ desc = acpi_find_gpio(dev, con_id, idx, flags, &lookupflags);
}
}
@@ -2829,6 +2875,9 @@ static int __init gpiolib_dev_init(void)
if (ret < 0) {
pr_err("gpiolib: failed to allocate char dev region\n");
bus_unregister(&gpio_bus_type);
+ } else {
+ gpiolib_initialized = true;
+ gpiochip_setup_devs();
}
return ret;
}