@@ -220,6 +220,9 @@ static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev,
/* Set owner */
pindesc->pctldev = pctldev;
+#ifdef CONFIG_PINMUX
+ spin_lock_init(&pindesc->mux_lock);
+#endif
/* Copy basic pin info */
if (pin->name) {
@@ -12,6 +12,7 @@
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/radix-tree.h>
+#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/pinctrl/machine.h>
@@ -177,6 +178,7 @@ struct pin_desc {
const char *mux_owner;
const struct pinctrl_setting_mux *mux_setting;
const char *gpio_owner;
+ spinlock_t mux_lock;
#endif
};
@@ -14,6 +14,7 @@
#include <linux/array_size.h>
#include <linux/ctype.h>
+#include <linux/cleanup.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/err.h>
@@ -127,29 +128,31 @@ static int pin_request(struct pinctrl_dev *pctldev,
dev_dbg(pctldev->dev, "request pin %d (%s) for %s\n",
pin, desc->name, owner);
- if ((!gpio_range || ops->strict) &&
- desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
- dev_err(pctldev->dev,
- "pin %s already requested by %s; cannot claim for %s\n",
- desc->name, desc->mux_owner, owner);
- goto out;
- }
+ scoped_guard(spinlock_irqsave, &desc->mux_lock) {
> Any reason to use spinlock_irqsave and not mutex ? If spinlock is needed
> can we guard only the mux variables and exclude the printk
> as the same lock is used with pin_show API too.
> Moreover, is the mux_usecount variable in pinmux_can_be_used_for_gpio()
> needed guarding ?
+ if ((!gpio_range || ops->strict) &&
+ desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
+ dev_err(pctldev->dev,
+ "pin %s already requested by %s; cannot claim for %s\n",
+ desc->name, desc->mux_owner, owner);
+ goto out;
+ }
- if ((gpio_range || ops->strict) && desc->gpio_owner) {
- dev_err(pctldev->dev,
- "pin %s already requested by %s; cannot claim for %s\n",
- desc->name, desc->gpio_owner, owner);
- goto out;
- }
+ if ((gpio_range || ops->strict) && desc->gpio_owner) {
+ dev_err(pctldev->dev,
+ "pin %s already requested by %s; cannot claim for %s\n",
+ desc->name, desc->gpio_owner, owner);
+ goto out;
+ }
- if (gpio_range) {
- desc->gpio_owner = owner;
- } else {
- desc->mux_usecount++;
- if (desc->mux_usecount > 1)
- return 0;
+ if (gpio_range) {
+ desc->gpio_owner = owner;
+ } else {
+ desc->mux_usecount++;
+ if (desc->mux_usecount > 1)
+ return 0;