iio: adc: ti-ads7950: switch to using guard() notation

guard() notation allows early returns when encountering errors, making
control flow more obvious. Use it.

Reviewed-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c
index 028acd42741f3d81f6440bba23f076ff2b91e792..6e9ea9cc33bff00c5989098e777517d068a4959d 100644 (file)
--- a/drivers/iio/adc/ti-ads7950.c
+++ b/drivers/iio/adc/ti-ads7950.c
@@ -299,18 +299,19 @@ static irqreturn_t ti_ads7950_trigger_handler(int irq, void *p)
        struct ti_ads7950_state *st = iio_priv(indio_dev);
        int ret;
 
-       mutex_lock(&st->slock);
-       ret = spi_sync(st->spi, &st->ring_msg);
-       if (ret < 0)
-               goto out;
-
-       iio_push_to_buffers_with_ts_unaligned(indio_dev, &st->rx_buf[2],
-                                             sizeof(*st->rx_buf) *
-                                             TI_ADS7950_MAX_CHAN,
-                                             iio_get_time_ns(indio_dev));
-
-out:
-       mutex_unlock(&st->slock);
+       do {
+               guard(mutex)(&st->slock);
+
+               ret = spi_sync(st->spi, &st->ring_msg);
+               if (ret)
+                       break;
+
+               iio_push_to_buffers_with_ts_unaligned(indio_dev, &st->rx_buf[2],
+                                                     sizeof(*st->rx_buf) *
+                                                     TI_ADS7950_MAX_CHAN,
+                                                     iio_get_time_ns(indio_dev));
+       } while (0);
+
        iio_trigger_notify_done(indio_dev->trig);
 
        return IRQ_HANDLED;
@@ -321,20 +322,16 @@ static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
        struct ti_ads7950_state *st = iio_priv(indio_dev);
        int ret, cmd;
 
-       mutex_lock(&st->slock);
+       guard(mutex)(&st->slock);
+
        cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(ch));
        st->single_tx = cmd;
 
        ret = spi_sync(st->spi, &st->scan_single_msg);
        if (ret)
-               goto out;
-
-       ret = st->single_rx;
-
-out:
-       mutex_unlock(&st->slock);
+               return ret;
 
-       return ret;
+       return st->single_rx;
 }
 
 static int ti_ads7950_get_range(struct ti_ads7950_state *st)
@@ -400,9 +397,8 @@ static int ti_ads7950_set(struct gpio_chip *chip, unsigned int offset,
                          int value)
 {
        struct ti_ads7950_state *st = gpiochip_get_data(chip);
-       int ret;
 
-       mutex_lock(&st->slock);
+       guard(mutex)(&st->slock);
 
        if (value)
                st->cmd_settings_bitmask |= BIT(offset);
@@ -410,11 +406,8 @@ static int ti_ads7950_set(struct gpio_chip *chip, unsigned int offset,
                st->cmd_settings_bitmask &= ~BIT(offset);
 
        st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
-       ret = spi_sync(st->spi, &st->scan_single_msg);
-
-       mutex_unlock(&st->slock);
 
-       return ret;
+       return spi_sync(st->spi, &st->scan_single_msg);
 }
 
 static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset)
@@ -423,13 +416,12 @@ static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset)
        bool state;
        int ret;
 
-       mutex_lock(&st->slock);
+       guard(mutex)(&st->slock);
 
        /* If set as output, return the output */
        if (st->gpio_cmd_settings_bitmask & BIT(offset)) {
                state = st->cmd_settings_bitmask & BIT(offset);
-               ret = 0;
-               goto out;
+               return state;
        }
 
        /* GPIO data bit sets SDO bits 12-15 to GPIO input */
@@ -437,7 +429,7 @@ static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset)
        st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
        ret = spi_sync(st->spi, &st->scan_single_msg);
        if (ret)
-               goto out;
+               return ret;
 
        state = (st->single_rx >> 12) & BIT(offset);
 
@@ -446,12 +438,9 @@ static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset)
        st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
        ret = spi_sync(st->spi, &st->scan_single_msg);
        if (ret)
-               goto out;
-
-out:
-       mutex_unlock(&st->slock);
+               return ret;
 
-       return ret ?: state;
+       return state;
 }
 
 static int ti_ads7950_get_direction(struct gpio_chip *chip,
@@ -467,9 +456,8 @@ static int _ti_ads7950_set_direction(struct gpio_chip *chip, int offset,
                                     int input)
 {
        struct ti_ads7950_state *st = gpiochip_get_data(chip);
-       int ret = 0;
 
-       mutex_lock(&st->slock);
+       guard(mutex)(&st->slock);
 
        /* Only change direction if needed */
        if (input && (st->gpio_cmd_settings_bitmask & BIT(offset)))
@@ -477,15 +465,11 @@ static int _ti_ads7950_set_direction(struct gpio_chip *chip, int offset,
        else if (!input && !(st->gpio_cmd_settings_bitmask & BIT(offset)))
                st->gpio_cmd_settings_bitmask |= BIT(offset);
        else
-               goto out;
+               return 0;
 
        st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st);
-       ret = spi_sync(st->spi, &st->scan_single_msg);
-
-out:
-       mutex_unlock(&st->slock);
 
-       return ret;
+       return spi_sync(st->spi, &st->scan_single_msg);
 }
 
 static int ti_ads7950_direction_input(struct gpio_chip *chip,
@@ -508,9 +492,9 @@ static int ti_ads7950_direction_output(struct gpio_chip *chip,
 
 static int ti_ads7950_init_hw(struct ti_ads7950_state *st)
 {
-       int ret = 0;
+       int ret;
 
-       mutex_lock(&st->slock);
+       guard(mutex)(&st->slock);
 
        /* Settings for Manual/Auto1/Auto2 commands */
        /* Default to 5v ref */
@@ -518,17 +502,12 @@ static int ti_ads7950_init_hw(struct ti_ads7950_state *st)
        st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
        ret = spi_sync(st->spi, &st->scan_single_msg);
        if (ret)
-               goto out;
+               return ret;
 
        /* Settings for GPIO command */
        st->gpio_cmd_settings_bitmask = 0x0;
        st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st);
-       ret = spi_sync(st->spi, &st->scan_single_msg);
-
-out:
-       mutex_unlock(&st->slock);
-
-       return ret;
+       return spi_sync(st->spi, &st->scan_single_msg);
 }
 
 static int ti_ads7950_probe(struct spi_device *spi)