[PATCH] iio:light:tsl2563: avoid flush_scheduled_work() usage

[PATCH] iio:light:tsl2563: avoid flush_scheduled_work() usage

[Tetsuo Handa]

Use local wq in order to avoid flush_scheduled_work() usage.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
---
Please see commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue()
using a macro") for background.

This is a blind conversion, and is only compile tested.

 drivers/iio/light/tsl2563.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/light/tsl2563.c b/drivers/iio/light/tsl2563.c
index 0a278eea36ca..0739fced0d34 100644
--- a/drivers/iio/light/tsl2563.c
+++ b/drivers/iio/light/tsl2563.c
@@ -75,6 +75,8 @@
 #define TSL2563_INT_LEVEL	0x10
 #define TSL2563_INT_PERSIST(n)	((n) & 0x0F)
 
+static struct workqueue_struct *tsl2563_wq;
+
 struct tsl2563_gainlevel_coeff {
 	u8 gaintime;
 	u16 min;
@@ -343,7 +345,7 @@ static int tsl2563_get_adc(struct tsl2563_chip *chip)
 	chip->data1 = tsl2563_normalize_adc(adc1, chip->gainlevel->gaintime);
 
 	if (!chip->int_enabled)
-		schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
+		queue_delayed_work(tsl2563_wq, &chip->poweroff_work, 5 * HZ);
 
 	ret = 0;
 out:
@@ -660,7 +662,7 @@ static int tsl2563_write_interrupt_config(struct iio_dev *indio_dev,
 						chip->intr);
 		chip->int_enabled = false;
 		/* now the interrupt is not enabled, we can go to sleep */
-		schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
+		queue_delayed_work(tsl2563_wq, &chip->poweroff_work, 5 * HZ);
 	}
 out:
 	mutex_unlock(&chip->lock);
@@ -781,7 +783,7 @@ static int tsl2563_probe(struct i2c_client *client,
 	INIT_DELAYED_WORK(&chip->poweroff_work, tsl2563_poweroff_work);
 
 	/* The interrupt cannot yet be enabled so this is fine without lock */
-	schedule_delayed_work(&chip->poweroff_work, 5 * HZ);
+	queue_delayed_work(tsl2563_wq, &chip->poweroff_work, 5 * HZ);
 
 	err = iio_device_register(indio_dev);
 	if (err) {
@@ -808,7 +810,7 @@ static int tsl2563_remove(struct i2c_client *client)
 	chip->intr &= ~0x30;
 	i2c_smbus_write_byte_data(chip->client, TSL2563_CMD | TSL2563_REG_INT,
 				  chip->intr);
-	flush_scheduled_work();
+	flush_workqueue(tsl2563_wq);
 	tsl2563_set_power(chip, 0);
 
 	return 0;
@@ -887,7 +889,27 @@ static struct i2c_driver tsl2563_i2c_driver = {
 	.remove		= tsl2563_remove,
 	.id_table	= tsl2563_id,
 };
-module_i2c_driver(tsl2563_i2c_driver);
+
+static int __init tsl2563_init(void)
+{
+	int ret;
+
+	tsl2563_wq = alloc_workqueue("tsl2563_wq", 0, 0);
+	if (!tsl2563_wq)
+		return -ENOMEM;
+	ret = i2c_add_driver(&tsl2563_i2c_driver);
+	if (ret)
+		destroy_workqueue(tsl2563_wq);
+	return ret;
+}
+module_init(tsl2563_init);
+
+static void __exit tsl2563_exit(void)
+{
+	i2c_del_driver(&tsl2563_i2c_driver);
+	destroy_workqueue(tsl2563_wq);
+}
+module_exit(tsl2563_exit);
 
 MODULE_AUTHOR("Nokia Corporation");
 MODULE_DESCRIPTION("tsl2563 light sensor driver");
-- 
2.18.4

[PATCH v2] iio:light:tsl2563: Replace flush_scheduled_work() with cancel_delayed_work_sync().

[Tetsuo Handa]

Commit 9e61d901155bcd4e ("iio: light: tsl2563: Remove
flush_scheduled_work") replaced cancel_delayed_work() +
flush_scheduled_work() with cancel_delayed_work_sync() for only
tsl2563_probe() side.

Do the same thing for tsl2563_remove() side, which was added by
commit 388be4883952872b ("staging:iio: tsl2563 abi fixes and interrupt
handling").

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
---
Changes in v2:
  Use cancel_delayed_work_sync() instead of introducing a dedicated WQ.

Please see commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue()
using a macro") for background.

 drivers/iio/light/tsl2563.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/iio/light/tsl2563.c b/drivers/iio/light/tsl2563.c
index 0a278eea36ca..4d89ac3a5bbc 100644
--- a/drivers/iio/light/tsl2563.c
+++ b/drivers/iio/light/tsl2563.c
@@ -803,12 +803,11 @@ static int tsl2563_remove(struct i2c_client *client)
 
 	iio_device_unregister(indio_dev);
 	if (!chip->int_enabled)
-		cancel_delayed_work(&chip->poweroff_work);
+		cancel_delayed_work_sync(&chip->poweroff_work);
 	/* Ensure that interrupts are disabled - then flush any bottom halves */
 	chip->intr &= ~0x30;
 	i2c_smbus_write_byte_data(chip->client, TSL2563_CMD | TSL2563_REG_INT,
 				  chip->intr);
-	flush_scheduled_work();
 	tsl2563_set_power(chip, 0);
 
 	return 0;
-- 
2.18.4

Re: [PATCH v2] iio:light:tsl2563: Replace flush_scheduled_work() with cancel_delayed_work_sync().

[Jonathan Cameron]

On Sun, 12 Jun 2022 23:52:59 +0900
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> wrote:

> Commit 9e61d901155bcd4e ("iio: light: tsl2563: Remove
> flush_scheduled_work") replaced cancel_delayed_work() +
> flush_scheduled_work() with cancel_delayed_work_sync() for only
> tsl2563_probe() side.
> 
> Do the same thing for tsl2563_remove() side, which was added by
> commit 388be4883952872b ("staging:iio: tsl2563 abi fixes and interrupt
> handling").
> 
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> ---
> Changes in v2:
>   Use cancel_delayed_work_sync() instead of introducing a dedicated WQ.
Nice.  This does the job without the complexity or overhead of a dedicated
work queue.  

Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to see if we missed anything.

Thanks,

Jonathqan

> 
> Please see commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue()
> using a macro") for background.
> 
>  drivers/iio/light/tsl2563.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/light/tsl2563.c b/drivers/iio/light/tsl2563.c
> index 0a278eea36ca..4d89ac3a5bbc 100644
> --- a/drivers/iio/light/tsl2563.c
> +++ b/drivers/iio/light/tsl2563.c
> @@ -803,12 +803,11 @@ static int tsl2563_remove(struct i2c_client *client)
>  
>  	iio_device_unregister(indio_dev);
>  	if (!chip->int_enabled)
> -		cancel_delayed_work(&chip->poweroff_work);
> +		cancel_delayed_work_sync(&chip->poweroff_work);
>  	/* Ensure that interrupts are disabled - then flush any bottom halves */
>  	chip->intr &= ~0x30;
>  	i2c_smbus_write_byte_data(chip->client, TSL2563_CMD | TSL2563_REG_INT,
>  				  chip->intr);
> -	flush_scheduled_work();
>  	tsl2563_set_power(chip, 0);
>  
>  	return 0;