linux-kernel - [PATCH v2] leds: lp5521/5523: Remove duplicate mutex

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Date:	Tue, 3 Dec 2013 10:21:44 +0900
From:	Milo Kim <milo.kim@...com>
To:	Bryan Wu <cooloney@...il.com>
CC:	<linux-kernel@...r.kernel.org>, <linux-leds@...r.kernel.org>,
	Milo Kim <milo.kim@...com>,
	Pali Rohár <pali.rohar@...il.com>
Subject: [PATCH v2] leds: lp5521/5523: Remove duplicate mutex

It can be a problem when a pattern is loaded via the firmware interface.
LP55xx common driver has already locked the mutex in 'lp55xx_firmware_loaded()'.
So it should be deleted.

On the other hand, locks are required in store_engine_load()
on updating program memory.

Cc: Pali Rohár <pali.rohar@...il.com>
Signed-off-by: Milo Kim <milo.kim@...com>
---
 drivers/leds/leds-lp5521.c |   12 ++++--------
 drivers/leds/leds-lp5523.c |   12 ++++--------
 2 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
index 26f89ac..2ec34cf 100644
--- a/drivers/leds/leds-lp5521.c
+++ b/drivers/leds/leds-lp5521.c
@@ -258,18 +258,12 @@ static int lp5521_update_program_memory(struct lp55xx_chip *chip,
 	if (i % 2)
 		goto err;
 
-	mutex_lock(&chip->lock);
-
 	for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
 		ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
-		if (ret) {
-			mutex_unlock(&chip->lock);
+		if (ret)
 			return -EINVAL;
-		}
 	}
 
-	mutex_unlock(&chip->lock);
-
 	return size;
 
 err:
@@ -441,15 +435,17 @@ static ssize_t store_engine_load(struct device *dev,
 {
 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 	struct lp55xx_chip *chip = led->chip;
+	int ret;
 
 	mutex_lock(&chip->lock);
 
 	chip->engine_idx = nr;
 	lp5521_load_engine(chip);
+	ret = lp5521_update_program_memory(chip, buf, len);
 
 	mutex_unlock(&chip->lock);
 
-	return lp5521_update_program_memory(chip, buf, len);
+	return ret;
 }
 store_load(1)
 store_load(2)
diff --git a/drivers/leds/leds-lp5523.c b/drivers/leds/leds-lp5523.c
index 2ce1723..bf21852 100644
--- a/drivers/leds/leds-lp5523.c
+++ b/drivers/leds/leds-lp5523.c
@@ -351,18 +351,12 @@ static int lp5523_update_program_memory(struct lp55xx_chip *chip,
 	if (i % 2)
 		goto err;
 
-	mutex_lock(&chip->lock);
-
 	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
 		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
-		if (ret) {
-			mutex_unlock(&chip->lock);
+		if (ret)
 			return -EINVAL;
-		}
 	}
 
-	mutex_unlock(&chip->lock);
-
 	return size;
 
 err:
@@ -562,15 +556,17 @@ static ssize_t store_engine_load(struct device *dev,
 {
 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 	struct lp55xx_chip *chip = led->chip;
+	int ret;
 
 	mutex_lock(&chip->lock);
 
 	chip->engine_idx = nr;
 	lp5523_load_engine_and_select_page(chip);
+	ret = lp5523_update_program_memory(chip, buf, len);
 
 	mutex_unlock(&chip->lock);
 
-	return lp5523_update_program_memory(chip, buf, len);
+	return ret;
 }
 store_load(1)
 store_load(2)
-- 
1.7.9.5

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