From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reduce the code complexity by using automatic lock guards with the I2C
mutex.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
drivers/gpio/gpio-adnp.c | 118 +++++++++++++++++++----------------------------
1 file changed, 47 insertions(+), 71 deletions(-)
diff --git a/drivers/gpio/gpio-adnp.c b/drivers/gpio/gpio-adnp.c
index 6dafab0cf964..dc87768276ec 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)
@@ -189,25 +179,24 @@ static void adnp_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
for (i = 0; i < num_regs; i++) {
u8 ddr, plr, ier, isr;
- 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)
@@ -252,28 +236,20 @@ static irqreturn_t adnp_irq(int irq, void *data)
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);
}
--
2.45.2Hi Bartosz,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 9778568dede2166c7bd124d473f9ec365f782935]
url: https://github.com/intel-lab-lkp/linux/commits/Bartosz-Golaszewski/gpio-74x164-use-new-line-value-setter-callbacks/20250303-212738
base: 9778568dede2166c7bd124d473f9ec365f782935
patch link: https://lore.kernel.org/r/20250303-gpiochip-set-conversion-v1-2-1d5cceeebf8b%40linaro.org
patch subject: [PATCH 02/15] gpio: adnp: use lock guards for the I2C lock
config: x86_64-buildonly-randconfig-001-20250304 (https://download.01.org/0day-ci/archive/20250304/202503041612.G8O0Bdrg-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250304/202503041612.G8O0Bdrg-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202503041612.G8O0Bdrg-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/gpio/gpio-adnp.c:241:8: warning: variable 'isr' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
241 | if (err < 0)
| ^~~~~~~
drivers/gpio/gpio-adnp.c:265:14: note: uninitialized use occurs here
265 | pending &= isr & ier;
| ^~~
drivers/gpio/gpio-adnp.c:241:4: note: remove the 'if' if its condition is always false
241 | if (err < 0)
| ^~~~~~~~~~~~
242 | continue;
| ~~~~~~~~
drivers/gpio/gpio-adnp.c:235:25: note: initialize the variable 'isr' to silence this warning
235 | u8 changed, level, isr, ier;
| ^
| = '\0'
>> drivers/gpio/gpio-adnp.c:245:8: warning: variable 'ier' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
245 | if (err < 0)
| ^~~~~~~
drivers/gpio/gpio-adnp.c:265:20: note: uninitialized use occurs here
265 | pending &= isr & ier;
| ^~~
drivers/gpio/gpio-adnp.c:245:4: note: remove the 'if' if its condition is always false
245 | if (err < 0)
| ^~~~~~~~~~~~
246 | continue;
| ~~~~~~~~
drivers/gpio/gpio-adnp.c:241:8: warning: variable 'ier' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
241 | if (err < 0)
| ^~~~~~~
drivers/gpio/gpio-adnp.c:265:20: note: uninitialized use occurs here
265 | pending &= isr & ier;
| ^~~
drivers/gpio/gpio-adnp.c:241:4: note: remove the 'if' if its condition is always false
241 | if (err < 0)
| ^~~~~~~~~~~~
242 | continue;
| ~~~~~~~~
drivers/gpio/gpio-adnp.c:235:30: note: initialize the variable 'ier' to silence this warning
235 | u8 changed, level, isr, ier;
| ^
| = '\0'
3 warnings generated.
vim +241 drivers/gpio/gpio-adnp.c
225
226 static irqreturn_t adnp_irq(int irq, void *data)
227 {
228 struct adnp *adnp = data;
229 unsigned int num_regs, i;
230
231 num_regs = 1 << adnp->reg_shift;
232
233 for (i = 0; i < num_regs; i++) {
234 unsigned int base = i << adnp->reg_shift, bit;
235 u8 changed, level, isr, ier;
236 unsigned long pending;
237 int err;
238
239 scoped_guard(mutex, &adnp->i2c_lock) {
240 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &level);
> 241 if (err < 0)
242 continue;
243
244 err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
> 245 if (err < 0)
246 continue;
247
248 err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
249 if (err < 0)
250 continue;
251 }
252
253 /* determine pins that changed levels */
254 changed = level ^ adnp->irq_level[i];
255
256 /* compute edge-triggered interrupts */
257 pending = changed & ((adnp->irq_fall[i] & ~level) |
258 (adnp->irq_rise[i] & level));
259
260 /* add in level-triggered interrupts */
261 pending |= (adnp->irq_high[i] & level) |
262 (adnp->irq_low[i] & ~level);
263
264 /* mask out non-pending and disabled interrupts */
265 pending &= isr & ier;
266
267 for_each_set_bit(bit, &pending, 8) {
268 unsigned int child_irq;
269 child_irq = irq_find_mapping(adnp->gpio.irq.domain,
270 base + bit);
271 handle_nested_irq(child_irq);
272 }
273 }
274
275 return IRQ_HANDLED;
276 }
277
--
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