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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.c84
1 files changed, 50 insertions, 34 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 94903fc1c145..fa62367ee929 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -101,6 +101,7 @@ static bool gpiolib_initialized;
const char *gpiod_get_label(struct gpio_desc *desc)
{
+ struct gpio_desc_label *label;
unsigned long flags;
flags = READ_ONCE(desc->flags);
@@ -108,23 +109,36 @@ const char *gpiod_get_label(struct gpio_desc *desc)
!test_bit(FLAG_REQUESTED, &flags))
return "interrupt";
- return test_bit(FLAG_REQUESTED, &flags) ?
- srcu_dereference(desc->label, &desc->srcu) : NULL;
+ if (!test_bit(FLAG_REQUESTED, &flags))
+ return NULL;
+
+ label = srcu_dereference_check(desc->label, &desc->gdev->desc_srcu,
+ srcu_read_lock_held(&desc->gdev->desc_srcu));
+
+ return label->str;
+}
+
+static void desc_free_label(struct rcu_head *rh)
+{
+ kfree(container_of(rh, struct gpio_desc_label, rh));
}
static int desc_set_label(struct gpio_desc *desc, const char *label)
{
- const char *new = NULL, *old;
+ struct gpio_desc_label *new = NULL, *old;
if (label) {
- new = kstrdup_const(label, GFP_KERNEL);
+ new = kzalloc(struct_size(new, str, strlen(label) + 1),
+ GFP_KERNEL);
if (!new)
return -ENOMEM;
+
+ strcpy(new->str, label);
}
old = rcu_replace_pointer(desc->label, new, 1);
- synchronize_srcu(&desc->srcu);
- kfree_const(old);
+ if (old)
+ call_srcu(&desc->gdev->desc_srcu, &old->rh, desc_free_label);
return 0;
}
@@ -150,9 +164,6 @@ struct gpio_desc *gpio_to_desc(unsigned gpio)
}
}
- if (!gpio_is_valid(gpio))
- pr_warn("invalid GPIO %d\n", gpio);
-
return NULL;
}
EXPORT_SYMBOL_GPL(gpio_to_desc);
@@ -297,10 +308,10 @@ struct gpio_chip *gpio_device_get_chip(struct gpio_device *gdev)
EXPORT_SYMBOL_GPL(gpio_device_get_chip);
/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
-static int gpiochip_find_base_unlocked(int ngpio)
+static int gpiochip_find_base_unlocked(u16 ngpio)
{
+ unsigned int base = GPIO_DYNAMIC_BASE;
struct gpio_device *gdev;
- int base = GPIO_DYNAMIC_BASE;
list_for_each_entry_srcu(gdev, &gpio_devices, list,
lockdep_is_held(&gpio_devices_lock)) {
@@ -311,9 +322,11 @@ static int gpiochip_find_base_unlocked(int ngpio)
base = gdev->base + gdev->ngpio;
if (base < GPIO_DYNAMIC_BASE)
base = GPIO_DYNAMIC_BASE;
+ if (base > GPIO_DYNAMIC_MAX - ngpio)
+ break;
}
- if (gpio_is_valid(base)) {
+ if (base <= GPIO_DYNAMIC_MAX - ngpio) {
pr_debug("%s: found new base at %d\n", __func__, base);
return base;
} else {
@@ -365,7 +378,10 @@ int gpiod_get_direction(struct gpio_desc *desc)
if (ret < 0)
return ret;
- /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
+ /*
+ * GPIO_LINE_DIRECTION_IN or other positive,
+ * otherwise GPIO_LINE_DIRECTION_OUT.
+ */
if (ret > 0)
ret = 1;
@@ -695,10 +711,10 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
static void gpiodev_release(struct device *dev)
{
struct gpio_device *gdev = to_gpio_device(dev);
- unsigned int i;
- for (i = 0; i < gdev->ngpio; i++)
- cleanup_srcu_struct(&gdev->descs[i].srcu);
+ /* Call pending kfree()s for descriptor labels. */
+ synchronize_srcu(&gdev->desc_srcu);
+ cleanup_srcu_struct(&gdev->desc_srcu);
ida_free(&gpio_ida, gdev->id);
kfree_const(gdev->label);
@@ -746,7 +762,7 @@ static int gpiochip_setup_dev(struct gpio_device *gdev)
if (ret)
goto err_remove_device;
- dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
+ dev_dbg(&gdev->dev, "registered GPIOs %u to %u on %s\n", gdev->base,
gdev->base + gdev->ngpio - 1, gdev->label);
return 0;
@@ -975,6 +991,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
if (ret)
goto err_remove_from_list;
+ ret = init_srcu_struct(&gdev->desc_srcu);
+ if (ret)
+ goto err_cleanup_gdev_srcu;
+
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&gdev->pin_ranges);
#endif
@@ -982,23 +1002,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
if (gc->names) {
ret = gpiochip_set_desc_names(gc);
if (ret)
- goto err_cleanup_gdev_srcu;
+ goto err_cleanup_desc_srcu;
}
ret = gpiochip_set_names(gc);
if (ret)
- goto err_cleanup_gdev_srcu;
+ goto err_cleanup_desc_srcu;
ret = gpiochip_init_valid_mask(gc);
if (ret)
- goto err_cleanup_gdev_srcu;
+ goto err_cleanup_desc_srcu;
for (desc_index = 0; desc_index < gc->ngpio; desc_index++) {
struct gpio_desc *desc = &gdev->descs[desc_index];
- ret = init_srcu_struct(&desc->srcu);
- if (ret)
- goto err_cleanup_desc_srcu;
-
if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) {
assign_bit(FLAG_IS_OUT,
&desc->flags, !gc->get_direction(gc, desc_index));
@@ -1010,7 +1026,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
ret = of_gpiochip_add(gc);
if (ret)
- goto err_cleanup_desc_srcu;
+ goto err_free_valid_mask;
ret = gpiochip_add_pin_ranges(gc);
if (ret)
@@ -1057,10 +1073,10 @@ err_free_hogs:
gpiochip_remove_pin_ranges(gc);
err_remove_of_chip:
of_gpiochip_remove(gc);
-err_cleanup_desc_srcu:
- while (desc_index--)
- cleanup_srcu_struct(&gdev->descs[desc_index].srcu);
+err_free_valid_mask:
gpiochip_free_valid_mask(gc);
+err_cleanup_desc_srcu:
+ cleanup_srcu_struct(&gdev->desc_srcu);
err_cleanup_gdev_srcu:
cleanup_srcu_struct(&gdev->srcu);
err_remove_from_list:
@@ -2390,7 +2406,7 @@ char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset)
if (!test_bit(FLAG_REQUESTED, &desc->flags))
return NULL;
- guard(srcu)(&desc->srcu);
+ guard(srcu)(&desc->gdev->desc_srcu);
label = kstrdup(gpiod_get_label(desc), GFP_KERNEL);
if (!label)
@@ -4240,7 +4256,7 @@ struct gpio_desc *gpiod_find_and_request(struct device *consumer,
ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
if (ret < 0) {
gpiod_put(desc);
- dev_dbg(consumer, "setup of GPIO %s failed\n", name);
+ dev_err(consumer, "setup of GPIO %s failed: %d\n", name, ret);
return ERR_PTR(ret);
}
@@ -4781,21 +4797,21 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
}
for_each_gpio_desc(gc, desc) {
- guard(srcu)(&desc->srcu);
+ guard(srcu)(&desc->gdev->desc_srcu);
if (test_bit(FLAG_REQUESTED, &desc->flags)) {
gpiod_get_direction(desc);
is_out = test_bit(FLAG_IS_OUT, &desc->flags);
value = gpio_chip_get_value(gc, desc);
is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);
active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);
- seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s\n",
+ seq_printf(s, " gpio-%-3u (%-20.20s|%-20.20s) %s %s %s%s\n",
gpio, desc->name ?: "", gpiod_get_label(desc),
is_out ? "out" : "in ",
value >= 0 ? (value ? "hi" : "lo") : "? ",
is_irq ? "IRQ " : "",
active_low ? "ACTIVE LOW" : "");
} else if (desc->name) {
- seq_printf(s, " gpio-%-3d (%-20.20s)\n", gpio, desc->name);
+ seq_printf(s, " gpio-%-3u (%-20.20s)\n", gpio, desc->name);
}
gpio++;
@@ -4867,7 +4883,7 @@ static int gpiolib_seq_show(struct seq_file *s, void *v)
return 0;
}
- seq_printf(s, "%s%s: GPIOs %d-%d", priv->newline ? "\n" : "",
+ seq_printf(s, "%s%s: GPIOs %u-%u", priv->newline ? "\n" : "",
dev_name(&gdev->dev),
gdev->base, gdev->base + gdev->ngpio - 1);
parent = gc->parent;
generated by cgit v1.2.3 (git 2.39.0) at 2024-08-16 17:15:17 +0300