On Sat, 23 Nov 2024 22:01:49 +0000
Jiasheng Jiang <jiashengjiangcool@xxxxxxxxx> wrote:
> Add check for the return value of clk_enable() in order to catch the
> potential exception.
>
> Reviewed-by: David Lechner <dlechner@xxxxxxxxxxxx>
> Signed-off-by: Jiasheng Jiang <jiashengjiangcool@xxxxxxxxx>
Applied.
thanks,
Jonathan
> ---
> Changelog:
>
> v4 -> v5:
>
> 1. Add a default in the switch.
>
> v3 -> v4:
>
> 1. Place braces around the case body.
>
> v2 -> v3:
>
> 1. Use guard() to simplify the resulting code.
>
> v1 -> v2:
>
> 1. Remove unsuitable dev_err_probe().
> ---
> drivers/iio/trigger/stm32-timer-trigger.c | 49 ++++++++++++++---------
> 1 file changed, 29 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c
> index 0684329956d9..67528ec7d0a5 100644
> --- a/drivers/iio/trigger/stm32-timer-trigger.c
> +++ b/drivers/iio/trigger/stm32-timer-trigger.c
> @@ -119,7 +119,7 @@ static int stm32_timer_start(struct stm32_timer_trigger *priv,
> unsigned int frequency)
> {
> unsigned long long prd, div;
> - int prescaler = 0;
> + int prescaler = 0, ret;
> u32 ccer;
>
> /* Period and prescaler values depends of clock rate */
> @@ -150,10 +150,12 @@ static int stm32_timer_start(struct stm32_timer_trigger *priv,
> if (ccer & TIM_CCER_CCXE)
> return -EBUSY;
>
> - mutex_lock(&priv->lock);
> + guard(mutex)(&priv->lock);
> if (!priv->enabled) {
> priv->enabled = true;
> - clk_enable(priv->clk);
> + ret = clk_enable(priv->clk);
> + if (ret)
> + return ret;
> }
>
> regmap_write(priv->regmap, TIM_PSC, prescaler);
> @@ -173,7 +175,6 @@ static int stm32_timer_start(struct stm32_timer_trigger *priv,
>
> /* Enable controller */
> regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
> - mutex_unlock(&priv->lock);
>
> return 0;
> }
> @@ -307,7 +308,7 @@ static ssize_t stm32_tt_store_master_mode(struct device *dev,
> struct stm32_timer_trigger *priv = dev_get_drvdata(dev);
> struct iio_trigger *trig = to_iio_trigger(dev);
> u32 mask, shift, master_mode_max;
> - int i;
> + int i, ret;
>
> if (stm32_timer_is_trgo2_name(trig->name)) {
> mask = TIM_CR2_MMS2;
> @@ -322,15 +323,16 @@ static ssize_t stm32_tt_store_master_mode(struct device *dev,
> for (i = 0; i <= master_mode_max; i++) {
> if (!strncmp(master_mode_table[i], buf,
> strlen(master_mode_table[i]))) {
> - mutex_lock(&priv->lock);
> + guard(mutex)(&priv->lock);
> if (!priv->enabled) {
> /* Clock should be enabled first */
> priv->enabled = true;
> - clk_enable(priv->clk);
> + ret = clk_enable(priv->clk);
> + if (ret)
> + return ret;
> }
> regmap_update_bits(priv->regmap, TIM_CR2, mask,
> i << shift);
> - mutex_unlock(&priv->lock);
> return len;
> }
> }
> @@ -482,6 +484,7 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,
> int val, int val2, long mask)
> {
> struct stm32_timer_trigger *priv = iio_priv(indio_dev);
> + int ret;
>
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> @@ -491,12 +494,14 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,
> /* fixed scale */
> return -EINVAL;
>
> - case IIO_CHAN_INFO_ENABLE:
> - mutex_lock(&priv->lock);
> + case IIO_CHAN_INFO_ENABLE: {
> + guard(mutex)(&priv->lock);
> if (val) {
> if (!priv->enabled) {
> priv->enabled = true;
> - clk_enable(priv->clk);
> + ret = clk_enable(priv->clk);
> + if (ret)
> + return ret;
> }
> regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
> } else {
> @@ -506,11 +511,12 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,
> clk_disable(priv->clk);
> }
> }
> - mutex_unlock(&priv->lock);
> +
> return 0;
> }
> -
> - return -EINVAL;
> + default:
> + return -EINVAL;
> + }
> }
>
> static int stm32_counter_validate_trigger(struct iio_dev *indio_dev,
> @@ -601,7 +607,7 @@ static int stm32_set_enable_mode(struct iio_dev *indio_dev,
> unsigned int mode)
> {
> struct stm32_timer_trigger *priv = iio_priv(indio_dev);
> - int sms = stm32_enable_mode2sms(mode);
> + int sms = stm32_enable_mode2sms(mode), ret;
>
> if (sms < 0)
> return sms;
> @@ -609,12 +615,15 @@ static int stm32_set_enable_mode(struct iio_dev *indio_dev,
> * Triggered mode sets CEN bit automatically by hardware. So, first
> * enable counter clock, so it can use it. Keeps it in sync with CEN.
> */
> - mutex_lock(&priv->lock);
> - if (sms == 6 && !priv->enabled) {
> - clk_enable(priv->clk);
> - priv->enabled = true;
> + scoped_guard(mutex, &priv->lock) {
> + if (sms == 6 && !priv->enabled) {
> + ret = clk_enable(priv->clk);
> + if (ret)
> + return ret;
> +
> + priv->enabled = true;
> + }
> }
> - mutex_unlock(&priv->lock);
>
> regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
>
