summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--drivers/gpio/gpio-shared-proxy.c76
-rw-r--r--drivers/gpio/gpiolib-shared.c9
-rw-r--r--drivers/gpio/gpiolib-shared.h28
3 files changed, 32 insertions, 81 deletions
diff --git a/drivers/gpio/gpio-shared-proxy.c b/drivers/gpio/gpio-shared-proxy.c
index 6941e4be6cf1..10ca2ef77ef3 100644
--- a/drivers/gpio/gpio-shared-proxy.c
+++ b/drivers/gpio/gpio-shared-proxy.c
@@ -9,8 +9,10 @@
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/driver.h>
+#include <linux/lockdep.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/string_choices.h>
#include <linux/types.h>
@@ -24,15 +26,13 @@ struct gpio_shared_proxy_data {
};
static int
-gpio_shared_proxy_set_unlocked(struct gpio_shared_proxy_data *proxy,
- int (*set_func)(struct gpio_desc *desc, int value),
- int value)
+gpio_shared_proxy_set_unlocked(struct gpio_shared_proxy_data *proxy, int value)
{
struct gpio_shared_desc *shared_desc = proxy->shared_desc;
struct gpio_desc *desc = shared_desc->desc;
int ret = 0;
- gpio_shared_lockdep_assert(shared_desc);
+ lockdep_assert_held(&shared_desc->mutex);
if (value) {
/* User wants to set value to high. */
@@ -46,7 +46,7 @@ gpio_shared_proxy_set_unlocked(struct gpio_shared_proxy_data *proxy,
* Current value is low, need to actually set value
* to high.
*/
- ret = set_func(desc, 1);
+ ret = gpiod_set_value_cansleep(desc, 1);
if (ret)
goto out;
}
@@ -65,7 +65,7 @@ gpio_shared_proxy_set_unlocked(struct gpio_shared_proxy_data *proxy,
/* We previously voted for high. */
if (shared_desc->highcnt == 1) {
/* This is the last remaining vote for high, set value to low. */
- ret = set_func(desc, 0);
+ ret = gpiod_set_value_cansleep(desc, 0);
if (ret)
goto out;
}
@@ -89,7 +89,7 @@ static int gpio_shared_proxy_request(struct gpio_chip *gc, unsigned int offset)
struct gpio_shared_proxy_data *proxy = gpiochip_get_data(gc);
struct gpio_shared_desc *shared_desc = proxy->shared_desc;
- guard(gpio_shared_desc_lock)(shared_desc);
+ guard(mutex)(&shared_desc->mutex);
proxy->shared_desc->usecnt++;
@@ -105,11 +105,10 @@ static void gpio_shared_proxy_free(struct gpio_chip *gc, unsigned int offset)
struct gpio_shared_desc *shared_desc = proxy->shared_desc;
int ret;
- guard(gpio_shared_desc_lock)(shared_desc);
+ guard(mutex)(&shared_desc->mutex);
if (proxy->voted_high) {
- ret = gpio_shared_proxy_set_unlocked(proxy,
- shared_desc->can_sleep ? gpiod_set_value_cansleep : gpiod_set_value, 0);
+ ret = gpio_shared_proxy_set_unlocked(proxy, 0);
if (ret)
dev_err(proxy->dev,
"Failed to unset the shared GPIO value on release: %d\n", ret);
@@ -129,7 +128,7 @@ static int gpio_shared_proxy_set_config(struct gpio_chip *gc,
struct gpio_desc *desc = shared_desc->desc;
int ret;
- guard(gpio_shared_desc_lock)(shared_desc);
+ guard(mutex)(&shared_desc->mutex);
if (shared_desc->usecnt > 1) {
if (shared_desc->cfg != cfg) {
@@ -157,7 +156,7 @@ static int gpio_shared_proxy_direction_input(struct gpio_chip *gc,
struct gpio_desc *desc = shared_desc->desc;
int dir;
- guard(gpio_shared_desc_lock)(shared_desc);
+ guard(mutex)(&shared_desc->mutex);
if (shared_desc->usecnt == 1) {
dev_dbg(proxy->dev,
@@ -187,7 +186,7 @@ static int gpio_shared_proxy_direction_output(struct gpio_chip *gc,
struct gpio_desc *desc = shared_desc->desc;
int ret, dir;
- guard(gpio_shared_desc_lock)(shared_desc);
+ guard(mutex)(&shared_desc->mutex);
if (shared_desc->usecnt == 1) {
dev_dbg(proxy->dev,
@@ -219,14 +218,7 @@ static int gpio_shared_proxy_direction_output(struct gpio_chip *gc,
return -EPERM;
}
- return gpio_shared_proxy_set_unlocked(proxy, gpiod_direction_output, value);
-}
-
-static int gpio_shared_proxy_get(struct gpio_chip *gc, unsigned int offset)
-{
- struct gpio_shared_proxy_data *proxy = gpiochip_get_data(gc);
-
- return gpiod_get_value(proxy->shared_desc->desc);
+ return gpio_shared_proxy_set_unlocked(proxy, value);
}
static int gpio_shared_proxy_get_cansleep(struct gpio_chip *gc,
@@ -237,29 +229,14 @@ static int gpio_shared_proxy_get_cansleep(struct gpio_chip *gc,
return gpiod_get_value_cansleep(proxy->shared_desc->desc);
}
-static int gpio_shared_proxy_do_set(struct gpio_shared_proxy_data *proxy,
- int (*set_func)(struct gpio_desc *desc, int value),
- int value)
-{
- guard(gpio_shared_desc_lock)(proxy->shared_desc);
-
- return gpio_shared_proxy_set_unlocked(proxy, set_func, value);
-}
-
-static int gpio_shared_proxy_set(struct gpio_chip *gc, unsigned int offset,
- int value)
-{
- struct gpio_shared_proxy_data *proxy = gpiochip_get_data(gc);
-
- return gpio_shared_proxy_do_set(proxy, gpiod_set_value, value);
-}
-
static int gpio_shared_proxy_set_cansleep(struct gpio_chip *gc,
unsigned int offset, int value)
{
struct gpio_shared_proxy_data *proxy = gpiochip_get_data(gc);
- return gpio_shared_proxy_do_set(proxy, gpiod_set_value_cansleep, value);
+ guard(mutex)(&proxy->shared_desc->mutex);
+
+ return gpio_shared_proxy_set_unlocked(proxy, value);
}
static int gpio_shared_proxy_get_direction(struct gpio_chip *gc,
@@ -302,20 +279,25 @@ static int gpio_shared_proxy_probe(struct auxiliary_device *adev,
gc->label = dev_name(dev);
gc->parent = dev;
gc->owner = THIS_MODULE;
- gc->can_sleep = shared_desc->can_sleep;
+ /*
+ * Under the descriptor mutex the proxy may call
+ * gpiod_set_config()/gpiod_direction_*(), which can reach pinctrl
+ * paths that take a mutex (e.g. gpiod_set_config() ->
+ * gpiochip_generic_config() -> pinctrl_gpio_set_config()), independent
+ * of the underlying chip's can_sleep. So the descriptor lock must be a
+ * mutex and the proxy gpiochip is therefore always sleeping; drive the
+ * underlying GPIO through the cansleep value accessors, which are valid
+ * for both sleeping and non-sleeping chips.
+ */
+ gc->can_sleep = true;
gc->request = gpio_shared_proxy_request;
gc->free = gpio_shared_proxy_free;
gc->set_config = gpio_shared_proxy_set_config;
gc->direction_input = gpio_shared_proxy_direction_input;
gc->direction_output = gpio_shared_proxy_direction_output;
- if (gc->can_sleep) {
- gc->set = gpio_shared_proxy_set_cansleep;
- gc->get = gpio_shared_proxy_get_cansleep;
- } else {
- gc->set = gpio_shared_proxy_set;
- gc->get = gpio_shared_proxy_get;
- }
+ gc->set = gpio_shared_proxy_set_cansleep;
+ gc->get = gpio_shared_proxy_get_cansleep;
gc->get_direction = gpio_shared_proxy_get_direction;
gc->to_irq = gpio_shared_proxy_to_irq;
diff --git a/drivers/gpio/gpiolib-shared.c b/drivers/gpio/gpiolib-shared.c
index de72776fb154..495bd3d0ddf0 100644
--- a/drivers/gpio/gpiolib-shared.c
+++ b/drivers/gpio/gpiolib-shared.c
@@ -627,8 +627,7 @@ static void gpio_shared_release(struct kref *kref)
shared_desc = entry->shared_desc;
gpio_device_put(shared_desc->desc->gdev);
- if (shared_desc->can_sleep)
- mutex_destroy(&shared_desc->mutex);
+ mutex_destroy(&shared_desc->mutex);
kfree(shared_desc);
entry->shared_desc = NULL;
}
@@ -659,11 +658,7 @@ gpiod_shared_desc_create(struct gpio_shared_entry *entry)
}
shared_desc->desc = &gdev->descs[entry->offset];
- shared_desc->can_sleep = gpiod_cansleep(shared_desc->desc);
- if (shared_desc->can_sleep)
- mutex_init(&shared_desc->mutex);
- else
- spin_lock_init(&shared_desc->spinlock);
+ mutex_init(&shared_desc->mutex);
return shared_desc;
}
diff --git a/drivers/gpio/gpiolib-shared.h b/drivers/gpio/gpiolib-shared.h
index 15e72a8dcdb1..bbdc0ab7b647 100644
--- a/drivers/gpio/gpiolib-shared.h
+++ b/drivers/gpio/gpiolib-shared.h
@@ -3,10 +3,7 @@
#ifndef __LINUX_GPIO_SHARED_H
#define __LINUX_GPIO_SHARED_H
-#include <linux/cleanup.h>
-#include <linux/lockdep.h>
#include <linux/mutex.h>
-#include <linux/spinlock.h>
struct gpio_device;
struct gpio_desc;
@@ -42,35 +39,12 @@ static inline int gpio_shared_add_proxy_lookup(struct device *consumer,
struct gpio_shared_desc {
struct gpio_desc *desc;
- bool can_sleep;
unsigned long cfg;
unsigned int usecnt;
unsigned int highcnt;
- union {
- struct mutex mutex;
- spinlock_t spinlock;
- };
+ struct mutex mutex; /* serializes all proxy operations on this descriptor */
};
struct gpio_shared_desc *devm_gpiod_shared_get(struct device *dev);
-DEFINE_LOCK_GUARD_1(gpio_shared_desc_lock, struct gpio_shared_desc,
- if (_T->lock->can_sleep)
- mutex_lock(&_T->lock->mutex);
- else
- spin_lock_irqsave(&_T->lock->spinlock, _T->flags),
- if (_T->lock->can_sleep)
- mutex_unlock(&_T->lock->mutex);
- else
- spin_unlock_irqrestore(&_T->lock->spinlock, _T->flags),
- unsigned long flags)
-
-static inline void gpio_shared_lockdep_assert(struct gpio_shared_desc *shared_desc)
-{
- if (shared_desc->can_sleep)
- lockdep_assert_held(&shared_desc->mutex);
- else
- lockdep_assert_held(&shared_desc->spinlock);
-}
-
#endif /* __LINUX_GPIO_SHARED_H */
generated by cgit v1.2.3 (git 2.25.1) at 2026-07-18 12:49:00 +0000