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[v3,5/7] iio: adc: exynos: Use input_device_enabled()

Message ID 20200605173335.13753-6-andrzej.p@collabora.com (mailing list archive)
State New, archived
Headers show
Series [v3,1/7] Input: add input_device_enabled() | expand

Commit Message

Andrzej Pietrasiewicz June 5, 2020, 5:33 p.m. UTC
A new helper is available, so use it. Inspecting 'users' member of
input_dev requires taking device's mutex.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
---
 drivers/iio/adc/exynos_adc.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

Comments

Michał Mirosław June 5, 2020, 7:49 p.m. UTC | #1
On Fri, Jun 05, 2020 at 07:33:33PM +0200, Andrzej Pietrasiewicz wrote:
> A new helper is available, so use it. Inspecting 'users' member of
> input_dev requires taking device's mutex.
> 
> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> ---
>  drivers/iio/adc/exynos_adc.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
> index 22131a677445..294715bafe25 100644
> --- a/drivers/iio/adc/exynos_adc.c
> +++ b/drivers/iio/adc/exynos_adc.c
> @@ -630,10 +630,13 @@ static irqreturn_t exynos_ts_isr(int irq, void *dev_id)
>  	struct exynos_adc *info = dev_id;
>  	struct iio_dev *dev = dev_get_drvdata(info->dev);
>  	u32 x, y;
> -	bool pressed;
> +	bool pressed, cont;
>  	int ret;
>  
> -	while (info->input->users) {
> +	mutex_lock(&info->input->mutex);
> +	cont = input_device_enabled(info->input);
> +	mutex_unlock(&info->input->mutex);
> +	while (cont) {
>  		ret = exynos_read_s3c64xx_ts(dev, &x, &y);
>  		if (ret == -ETIMEDOUT)
>  			break;
> @@ -651,6 +654,10 @@ static irqreturn_t exynos_ts_isr(int irq, void *dev_id)
>  		input_sync(info->input);
>  
>  		usleep_range(1000, 1100);
> +
> +		mutex_lock(&info->input->mutex);
> +		cont = input_device_enabled(info->input);
> +		mutex_unlock(&info->input->mutex);
>  	}

The mutex doesn't really protect anything here, but I would nevertheless
suggest this sequence instead:

lock()
while (test) {
	unlock()
	...
	lock()
}
unlock()

Best Regards,
Michał Mirosław
diff mbox series

Patch

diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index 22131a677445..294715bafe25 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -630,10 +630,13 @@  static irqreturn_t exynos_ts_isr(int irq, void *dev_id)
 	struct exynos_adc *info = dev_id;
 	struct iio_dev *dev = dev_get_drvdata(info->dev);
 	u32 x, y;
-	bool pressed;
+	bool pressed, cont;
 	int ret;
 
-	while (info->input->users) {
+	mutex_lock(&info->input->mutex);
+	cont = input_device_enabled(info->input);
+	mutex_unlock(&info->input->mutex);
+	while (cont) {
 		ret = exynos_read_s3c64xx_ts(dev, &x, &y);
 		if (ret == -ETIMEDOUT)
 			break;
@@ -651,6 +654,10 @@  static irqreturn_t exynos_ts_isr(int irq, void *dev_id)
 		input_sync(info->input);
 
 		usleep_range(1000, 1100);
+
+		mutex_lock(&info->input->mutex);
+		cont = input_device_enabled(info->input);
+		mutex_unlock(&info->input->mutex);
 	}
 
 	writel(0, ADC_V1_CLRINTPNDNUP(info->regs));