[PATCH] iio: adc: ingenic-adc: use guard(mutex)(&lock) to handle synchronisation

[Felipe Ribeiro de Souza]

Replace mutex_lock(&lock) and mutex_unlock(&lock) calls with guard(mutex)(&lock)
in functions ingenic_adc_set_adcmd, ingenic_adc_set_config, ingenic_adc_enable,
ingenic_adc_capture and ingenic_adc_read_chan_info_raw.

This removes the need to call the unlock function, as the lock is automatically
released when the function return or the scope exits for any other case.

Signed-off-by: Felipe Ribeiro de Souza <felipers em usp.br>
Co-developed-by: Lucas Ivars Cadima Ciziks <lucas em ciziks.com>
Signed-off-by: Lucas Ivars Cadima Ciziks <lucas em ciziks.com>
---
 drivers/iio/adc/ingenic-adc.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
index 1e802c877..bb7abdcd8 100644
--- a/drivers/iio/adc/ingenic-adc.c
+++ b/drivers/iio/adc/ingenic-adc.c
@@ -20,6 +20,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
+#include <linux/cleanup.h>
 
 #define JZ_ADC_REG_ENABLE		0x00
 #define JZ_ADC_REG_CFG			0x04
@@ -115,7 +116,7 @@ static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, unsigned long mask)
 {
 	struct ingenic_adc *adc = iio_priv(iio_dev);
 
-	mutex_lock(&adc->lock);
+	guard(mutex)(&adc->lock);
 
 	/* Init ADCMD */
 	readl(adc->base + JZ_ADC_REG_ADCMD);
@@ -162,8 +163,6 @@ static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, unsigned long mask)
 
 	/* We're done */
 	writel(0, adc->base + JZ_ADC_REG_ADCMD);
-
-	mutex_unlock(&adc->lock);
 }
 
 static void ingenic_adc_set_config(struct ingenic_adc *adc,
@@ -172,13 +171,11 @@ static void ingenic_adc_set_config(struct ingenic_adc *adc,
 {
 	uint32_t cfg;
 
-	mutex_lock(&adc->lock);
+	guard(mutex)(&adc->lock);
 
 	cfg = readl(adc->base + JZ_ADC_REG_CFG) & ~mask;
 	cfg |= val;
 	writel(cfg, adc->base + JZ_ADC_REG_CFG);
-
-	mutex_unlock(&adc->lock);
 }
 
 static void ingenic_adc_enable_unlocked(struct ingenic_adc *adc,
@@ -201,9 +198,8 @@ static void ingenic_adc_enable(struct ingenic_adc *adc,
 			       int engine,
 			       bool enabled)
 {
-	mutex_lock(&adc->lock);
+	guard(mutex)(&adc->lock);
 	ingenic_adc_enable_unlocked(adc, engine, enabled);
-	mutex_unlock(&adc->lock);
 }
 
 static int ingenic_adc_capture(struct ingenic_adc *adc,
@@ -218,7 +214,7 @@ static int ingenic_adc_capture(struct ingenic_adc *adc,
 	 * probably due to the switch of VREF. We must keep the lock here to
 	 * avoid races with the buffer enable/disable functions.
 	 */
-	mutex_lock(&adc->lock);
+	guard(mutex)(&adc->lock);
 	cfg = readl(adc->base + JZ_ADC_REG_CFG);
 	writel(cfg & ~JZ_ADC_REG_CFG_CMD_SEL, adc->base + JZ_ADC_REG_CFG);
 
@@ -229,7 +225,6 @@ static int ingenic_adc_capture(struct ingenic_adc *adc,
 		ingenic_adc_enable_unlocked(adc, engine, false);
 
 	writel(cfg, adc->base + JZ_ADC_REG_CFG);
-	mutex_unlock(&adc->lock);
 
 	return ret;
 }
@@ -643,7 +638,8 @@ static int ingenic_adc_read_chan_info_raw(struct iio_dev *iio_dev,
 	}
 
 	/* We cannot sample the aux channels in parallel. */
-	mutex_lock(&adc->aux_lock);
+	guard(mutex)(&adc->lock);
+
 	if (adc->soc_data->has_aux_md && engine == 0) {
 		switch (chan->channel) {
 		case INGENIC_ADC_AUX0:
@@ -677,7 +673,6 @@ static int ingenic_adc_read_chan_info_raw(struct iio_dev *iio_dev,
 
 	ret = IIO_VAL_INT;
 out:
-	mutex_unlock(&adc->aux_lock);
 	clk_disable(adc->clk);
 
 	return ret;
-- 
2.43.0