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Message-Id: <20250306-gpiochip-set-conversion-v2-1-a76e72e21425@linaro.org>
Date: Thu, 06 Mar 2025 18:19:26 +0100
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Linus Walleij <linus.walleij@...aro.org>,
Bartosz Golaszewski <brgl@...ev.pl>
Cc: linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org,
Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH v2 1/2] gpio: adnp: use lock guards for the I2C lock
From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Reduce the code complexity by using automatic lock guards with the I2C
mutex.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
drivers/gpio/gpio-adnp.c | 122 +++++++++++++++++++----------------------------
1 file changed, 49 insertions(+), 73 deletions(-)
diff --git a/drivers/gpio/gpio-adnp.c b/drivers/gpio/gpio-adnp.c
index 6dafab0cf964..1a282cba8489 100644
--- a/drivers/gpio/gpio-adnp.c
+++ b/drivers/gpio/gpio-adnp.c
@@ -3,6 +3,7 @@
* Copyright (C) 2011-2012 Avionic Design GmbH
*/
+#include <linux/cleanup.h>
#include <linux/gpio/driver.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
@@ -101,9 +102,9 @@ static void adnp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct adnp *adnp = gpiochip_get_data(chip);
- mutex_lock(&adnp->i2c_lock);
+ guard(mutex)(&adnp->i2c_lock);
+
__adnp_gpio_set(adnp, offset, value);
- mutex_unlock(&adnp->i2c_lock);
}
static int adnp_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
@@ -114,32 +115,26 @@ static int adnp_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
u8 value;
int err;
- mutex_lock(&adnp->i2c_lock);
+ guard(mutex)(&adnp->i2c_lock);
err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &value);
if (err < 0)
- goto out;
+ return err;
value &= ~BIT(pos);
err = adnp_write(adnp, GPIO_DDR(adnp) + reg, value);
if (err < 0)
- goto out;
+ return err;
err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &value);
if (err < 0)
- goto out;
+ return err;
- if (value & BIT(pos)) {
- err = -EPERM;
- goto out;
- }
+ if (value & BIT(pos))
+ return -EPERM;
- err = 0;
-
-out:
- mutex_unlock(&adnp->i2c_lock);
- return err;
+ return 0;
}
static int adnp_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
@@ -151,33 +146,28 @@ static int adnp_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
int err;
u8 val;
- mutex_lock(&adnp->i2c_lock);
+ guard(mutex)(&adnp->i2c_lock);
err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &val);
if (err < 0)
- goto out;
+ return err;
val |= BIT(pos);
err = adnp_write(adnp, GPIO_DDR(adnp) + reg, val);
if (err < 0)
- goto out;
+ return err;
err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &val);
if (err < 0)
- goto out;
+ return err;
- if (!(val & BIT(pos))) {
- err = -EPERM;
- goto out;
- }
+ if (!(val & BIT(pos)))
+ return -EPERM;
__adnp_gpio_set(adnp, offset, value);
- err = 0;
-out:
- mutex_unlock(&adnp->i2c_lock);
- return err;
+ return 0;
}
static void adnp_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
@@ -187,27 +177,26 @@ static void adnp_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
int err;
for (i = 0; i < num_regs; i++) {
- u8 ddr, plr, ier, isr;
+ u8 ddr = 0, plr = 0, ier = 0, isr = 0;
- mutex_lock(&adnp->i2c_lock);
+ scoped_guard(mutex, &adnp->i2c_lock) {
+ err = adnp_read(adnp, GPIO_DDR(adnp) + i, &ddr);
+ if (err < 0)
+ return;
- err = adnp_read(adnp, GPIO_DDR(adnp) + i, &ddr);
- if (err < 0)
- goto unlock;
+ err = adnp_read(adnp, GPIO_PLR(adnp) + i, &plr);
+ if (err < 0)
+ return;
- err = adnp_read(adnp, GPIO_PLR(adnp) + i, &plr);
- if (err < 0)
- goto unlock;
+ err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
+ if (err < 0)
+ return;
- err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
- if (err < 0)
- goto unlock;
+ err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
+ if (err < 0)
+ return;
- err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
- if (err < 0)
- goto unlock;
-
- mutex_unlock(&adnp->i2c_lock);
+ }
for (j = 0; j < 8; j++) {
unsigned int bit = (i << adnp->reg_shift) + j;
@@ -232,11 +221,6 @@ static void adnp_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
direction, level, interrupt, pending);
}
}
-
- return;
-
-unlock:
- mutex_unlock(&adnp->i2c_lock);
}
static irqreturn_t adnp_irq(int irq, void *data)
@@ -248,32 +232,24 @@ static irqreturn_t adnp_irq(int irq, void *data)
for (i = 0; i < num_regs; i++) {
unsigned int base = i << adnp->reg_shift, bit;
- u8 changed, level, isr, ier;
+ u8 changed, level = 0, isr = 0, ier = 0;
unsigned long pending;
int err;
- mutex_lock(&adnp->i2c_lock);
+ scoped_guard(mutex, &adnp->i2c_lock) {
+ err = adnp_read(adnp, GPIO_PLR(adnp) + i, &level);
+ if (err < 0)
+ continue;
- err = adnp_read(adnp, GPIO_PLR(adnp) + i, &level);
- if (err < 0) {
- mutex_unlock(&adnp->i2c_lock);
- continue;
+ err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
+ if (err < 0)
+ continue;
+
+ err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
+ if (err < 0)
+ continue;
}
- err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
- if (err < 0) {
- mutex_unlock(&adnp->i2c_lock);
- continue;
- }
-
- err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
- if (err < 0) {
- mutex_unlock(&adnp->i2c_lock);
- continue;
- }
-
- mutex_unlock(&adnp->i2c_lock);
-
/* determine pins that changed levels */
changed = level ^ adnp->irq_level[i];
@@ -365,12 +341,12 @@ static void adnp_irq_bus_unlock(struct irq_data *d)
struct adnp *adnp = gpiochip_get_data(gc);
unsigned int num_regs = 1 << adnp->reg_shift, i;
- mutex_lock(&adnp->i2c_lock);
+ scoped_guard(mutex, &adnp->i2c_lock) {
+ for (i = 0; i < num_regs; i++)
+ adnp_write(adnp, GPIO_IER(adnp) + i,
+ adnp->irq_enable[i]);
+ }
- for (i = 0; i < num_regs; i++)
- adnp_write(adnp, GPIO_IER(adnp) + i, adnp->irq_enable[i]);
-
- mutex_unlock(&adnp->i2c_lock);
mutex_unlock(&adnp->irq_lock);
}
--
2.45.2
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