From 1bbeff1c53f90475f79c7078ce65e2d4e1fac2ee Mon Sep 17 00:00:00 2001 From: Bengt Jonsson Date: Wed, 10 Nov 2010 11:06:22 +0100 Subject: regulator: enable supply regulator only when use count is zero Supply regulators are disabled only when the last reference count is removed on the child regulator (the use count goes from 1 to 0). This patch changes the behaviour of enable so the supply regulator is enabled only when the use count of the child regulator goes from 0 to 1. Signed-off-by: Bengt Jonsson Acked-by: Linus Walleij Acked-by: Mark Brown Signed-off-by: Liam Girdwood Reviewed-on: http://git.kernel.org/?p=linux/kernel/git/torvalds/ linux-2.6.git;a=commit;h=acaf6ffefdf65188071f88664435b86651d70e7c Change-Id: I145643ad26a461e63f4bf2cb21bda6b05425c5a2 Reviewed-on: http://git-master/r/30953 Tested-by: Varun Wadekar Reviewed-by: Scott Williams Reviewed-by: Daniel Willemsen --- drivers/regulator/core.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'drivers/regulator') diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 347b4be5c898..4a93e8cc0bf1 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1264,13 +1264,17 @@ static int _regulator_enable(struct regulator_dev *rdev) { int ret, delay; - /* do we need to enable the supply regulator first */ - if (rdev->supply) { - ret = _regulator_enable(rdev->supply); - if (ret < 0) { - printk(KERN_ERR "%s: failed to enable %s: %d\n", - __func__, rdev_get_name(rdev), ret); - return ret; + if (rdev->use_count == 0) { + /* do we need to enable the supply regulator first */ + if (rdev->supply) { + mutex_lock(&rdev->supply->mutex); + ret = _regulator_enable(rdev->supply); + mutex_unlock(&rdev->supply->mutex); + if (ret < 0) { + printk(KERN_ERR "%s: failed to enable %s: %d\n", + __func__, rdev_get_name(rdev), ret); + return ret; + } } } -- cgit v1.2.3