[PATCH/RFC v6 15/36] leds: blinkm: Remove work queue

From: Jacek Anaszewski
Date: Thu Aug 20 2015 - 10:46:43 EST


From: Andrew Lunn <andrew@xxxxxxx>

Now the core implements the work queue, remove it from the driver,
and switch to using brightness_set_blocking op.

Signed-off-by: Andrew Lunn <andrew@xxxxxxx>
Cc: Jan-Simon Moeller <dl9pf@xxxxxx>
Signed-off-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
---
drivers/leds/leds-blinkm.c | 87 +++++++++-----------------------------------
1 file changed, 17 insertions(+), 70 deletions(-)

diff --git a/drivers/leds/leds-blinkm.c b/drivers/leds/leds-blinkm.c
index d0452b0..617fe97 100644
--- a/drivers/leds/leds-blinkm.c
+++ b/drivers/leds/leds-blinkm.c
@@ -39,16 +39,9 @@ struct blinkm_led {
struct i2c_client *i2c_client;
struct led_classdev led_cdev;
int id;
- atomic_t active;
-};
-
-struct blinkm_work {
- struct blinkm_led *blinkm_led;
- struct work_struct work;
};

#define cdev_to_blmled(c) container_of(c, struct blinkm_led, led_cdev)
-#define work_to_blmwork(c) container_of(c, struct blinkm_work, work)

struct blinkm_data {
struct i2c_client *i2c_client;
@@ -439,65 +432,30 @@ static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
return 0;
}

-static void led_work(struct work_struct *work)
-{
- int ret;
- struct blinkm_led *led;
- struct blinkm_data *data;
- struct blinkm_work *blm_work = work_to_blmwork(work);
-
- led = blm_work->blinkm_led;
- data = i2c_get_clientdata(led->i2c_client);
- ret = blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
- atomic_dec(&led->active);
- dev_dbg(&led->i2c_client->dev,
- "# DONE # next_red = %d, next_green = %d,"
- " next_blue = %d, active = %d\n",
- data->next_red, data->next_green,
- data->next_blue, atomic_read(&led->active));
- kfree(blm_work);
-}
-
static int blinkm_led_common_set(struct led_classdev *led_cdev,
enum led_brightness value, int color)
{
/* led_brightness is 0, 127 or 255 - we just use it here as-is */
struct blinkm_led *led = cdev_to_blmled(led_cdev);
struct blinkm_data *data = i2c_get_clientdata(led->i2c_client);
- struct blinkm_work *bl_work;

switch (color) {
case RED:
/* bail out if there's no change */
if (data->next_red == (u8) value)
return 0;
- /* we assume a quite fast sequence here ([off]->on->off)
- * think of network led trigger - we cannot blink that fast, so
- * in case we already have a off->on->off transition queued up,
- * we refuse to queue up more.
- * Revisit: fast-changing brightness. */
- if (atomic_read(&led->active) > 1)
- return 0;
data->next_red = (u8) value;
break;
case GREEN:
/* bail out if there's no change */
if (data->next_green == (u8) value)
return 0;
- /* we assume a quite fast sequence here ([off]->on->off)
- * Revisit: fast-changing brightness. */
- if (atomic_read(&led->active) > 1)
- return 0;
data->next_green = (u8) value;
break;
case BLUE:
/* bail out if there's no change */
if (data->next_blue == (u8) value)
return 0;
- /* we assume a quite fast sequence here ([off]->on->off)
- * Revisit: fast-changing brightness. */
- if (atomic_read(&led->active) > 1)
- return 0;
data->next_blue = (u8) value;
break;

@@ -506,42 +464,31 @@ static int blinkm_led_common_set(struct led_classdev *led_cdev,
return -EINVAL;
}

- bl_work = kzalloc(sizeof(*bl_work), GFP_ATOMIC);
- if (!bl_work)
- return -ENOMEM;
-
- atomic_inc(&led->active);
+ blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
dev_dbg(&led->i2c_client->dev,
- "#TO_SCHED# next_red = %d, next_green = %d,"
- " next_blue = %d, active = %d\n",
+ "# DONE # next_red = %d, next_green = %d,"
+ " next_blue = %d\n",
data->next_red, data->next_green,
- data->next_blue, atomic_read(&led->active));
-
- /* a fresh work _item_ for each change */
- bl_work->blinkm_led = led;
- INIT_WORK(&bl_work->work, led_work);
- /* queue work in own queue for easy sync on exit*/
- schedule_work(&bl_work->work);
-
+ data->next_blue);
return 0;
}

-static void blinkm_led_red_set(struct led_classdev *led_cdev,
+static int blinkm_led_red_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
- blinkm_led_common_set(led_cdev, value, RED);
+ return blinkm_led_common_set(led_cdev, value, RED);
}

-static void blinkm_led_green_set(struct led_classdev *led_cdev,
+static int blinkm_led_green_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
- blinkm_led_common_set(led_cdev, value, GREEN);
+ return blinkm_led_common_set(led_cdev, value, GREEN);
}

-static void blinkm_led_blue_set(struct led_classdev *led_cdev,
+static int blinkm_led_blue_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
- blinkm_led_common_set(led_cdev, value, BLUE);
+ return blinkm_led_common_set(led_cdev, value, BLUE);
}

static void blinkm_init_hw(struct i2c_client *client)
@@ -669,7 +616,6 @@ static int blinkm_probe(struct i2c_client *client,
led[i]->id = i;
led[i]->led_cdev.max_brightness = 255;
led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
- atomic_set(&led[i]->active, 0);
switch (i) {
case RED:
snprintf(blinkm_led_name, sizeof(blinkm_led_name),
@@ -677,7 +623,8 @@ static int blinkm_probe(struct i2c_client *client,
client->adapter->nr,
client->addr);
led[i]->led_cdev.name = blinkm_led_name;
- led[i]->led_cdev.brightness_set = blinkm_led_red_set;
+ led[i]->led_cdev.brightness_set_blocking =
+ blinkm_led_red_set;
err = led_classdev_register(&client->dev,
&led[i]->led_cdev);
if (err < 0) {
@@ -693,7 +640,8 @@ static int blinkm_probe(struct i2c_client *client,
client->adapter->nr,
client->addr);
led[i]->led_cdev.name = blinkm_led_name;
- led[i]->led_cdev.brightness_set = blinkm_led_green_set;
+ led[i]->led_cdev.brightness_set_blocking =
+ blinkm_led_green_set;
err = led_classdev_register(&client->dev,
&led[i]->led_cdev);
if (err < 0) {
@@ -709,7 +657,8 @@ static int blinkm_probe(struct i2c_client *client,
client->adapter->nr,
client->addr);
led[i]->led_cdev.name = blinkm_led_name;
- led[i]->led_cdev.brightness_set = blinkm_led_blue_set;
+ led[i]->led_cdev.brightness_set_blocking =
+ blinkm_led_blue_set;
err = led_classdev_register(&client->dev,
&led[i]->led_cdev);
if (err < 0) {
@@ -746,10 +695,8 @@ static int blinkm_remove(struct i2c_client *client)
int i;

/* make sure no workqueue entries are pending */
- for (i = 0; i < 3; i++) {
- flush_scheduled_work();
+ for (i = 0; i < 3; i++)
led_classdev_unregister(&data->blinkm_leds[i].led_cdev);
- }

/* reset rgb */
data->next_red = 0x00;
--
1.7.9.5

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