Commit c7fe19ed authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpio: adnp: use lock guards for the I2C lock 

Reduce the code complexity by using automatic lock guards with the I2C
mutex.

Link: https://lore.kernel.org/r/20250306-gpiochip-set-conversion-v2-1-a76e72e21425@linaro.org


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent 46056010

drivers/gpio/gpio-adnp.c

+48 −72
Original line number Diff line number Diff line
@@ -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>
@@ -102,9 +103,9 @@ 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)
@@ -115,32 +116,26 @@ 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;



	if (value & BIT(pos)) {

		err = -EPERM;

		goto out;

	}

		return err;



	err = 0;

	if (value & BIT(pos))

		return -EPERM;



out:

	mutex_unlock(&adnp->i2c_lock);

	return err;

	return 0;

}



static int adnp_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
@@ -152,33 +147,28 @@ 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)
@@ -188,27 +178,26 @@ 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;



		mutex_lock(&adnp->i2c_lock);

		u8 ddr = 0, plr = 0, ier = 0, isr = 0;



		scoped_guard(mutex, &adnp->i2c_lock) {

			err = adnp_read(adnp, GPIO_DDR(adnp) + i, &ddr);

			if (err < 0)

			goto unlock;

				return;



			err = adnp_read(adnp, GPIO_PLR(adnp) + i, &plr);

			if (err < 0)

			goto unlock;

				return;



			err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);

			if (err < 0)

			goto unlock;

				return;



			err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);

			if (err < 0)

			goto unlock;

				return;



		mutex_unlock(&adnp->i2c_lock);

		}



		for (j = 0; j < 8; j++) {

			unsigned int bit = (i << adnp->reg_shift) + j;
@@ -233,11 +222,6 @@ 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)
@@ -249,32 +233,24 @@ 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) {

			mutex_unlock(&adnp->i2c_lock);

			if (err < 0)

				continue;

		}



			err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);

		if (err < 0) {

			mutex_unlock(&adnp->i2c_lock);

			if (err < 0)

				continue;

		}



			err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);

		if (err < 0) {

			mutex_unlock(&adnp->i2c_lock);

			if (err < 0)

				continue;

		}



		mutex_unlock(&adnp->i2c_lock);



		/* determine pins that changed levels */

		changed = level ^ adnp->irq_level[i];
@@ -366,12 +342,12 @@ 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]);

			adnp_write(adnp, GPIO_IER(adnp) + i,

				   adnp->irq_enable[i]);

	}



	mutex_unlock(&adnp->i2c_lock);

	mutex_unlock(&adnp->irq_lock);

}