@@ -1764,10 +1764,12 @@ static int _regulator_do_enable(struct regulator_dev *rdev)
trace_regulator_enable(rdev_get_name(rdev));
if (rdev->ena_pin) {
- ret = regulator_ena_gpio_ctrl(rdev, true);
- if (ret < 0)
- return ret;
- rdev->ena_gpio_state = 1;
+ if (!rdev->ena_gpio_state) {
+ ret = regulator_ena_gpio_ctrl(rdev, true);
+ if (ret < 0)
+ return ret;
+ rdev->ena_gpio_state = 1;
+ }
} else if (rdev->desc->ops->enable) {
ret = rdev->desc->ops->enable(rdev);
if (ret < 0)
@@ -1897,10 +1899,12 @@ static int _regulator_do_disable(struct regulator_dev *rdev)
trace_regulator_disable(rdev_get_name(rdev));
if (rdev->ena_pin) {
- ret = regulator_ena_gpio_ctrl(rdev, false);
- if (ret < 0)
- return ret;
- rdev->ena_gpio_state = 0;
+ if (rdev->ena_gpio_state) {
+ ret = regulator_ena_gpio_ctrl(rdev, false);
+ if (ret < 0)
+ return ret;
+ rdev->ena_gpio_state = 0;
+ }
} else if (rdev->desc->ops->disable) {
ret = rdev->desc->ops->disable(rdev);
@@ -3454,12 +3458,6 @@ regulator_register(const struct regulator_desc *regulator_desc,
config->ena_gpio, ret);
goto wash;
}
-
- if (config->ena_gpio_flags & GPIOF_OUT_INIT_HIGH)
- rdev->ena_gpio_state = 1;
-
- if (config->ena_gpio_invert)
- rdev->ena_gpio_state = !rdev->ena_gpio_state;
}
/* set regulator constraints */
This is a note to let you know that I have just added a patch titled regulator: core: Fix enable GPIO reference counting to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11-ckt19. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From ca32d77443df505829db800366dc46536a34b904 Mon Sep 17 00:00:00 2001 From: Doug Anderson <dianders@chromium.org> Date: Tue, 3 Mar 2015 15:20:47 -0800 Subject: regulator: core: Fix enable GPIO reference counting commit 29d62ec5f87fbeec8413e2215ddad12e7f972e4c upstream. Normally _regulator_do_enable() isn't called on an already-enabled rdev. That's because the main caller, _regulator_enable() always calls _regulator_is_enabled() and only calls _regulator_do_enable() if the rdev was not already enabled. However, there is one caller of _regulator_do_enable() that doesn't check: regulator_suspend_finish(). While we might want to make regulator_suspend_finish() behave more like _regulator_enable(), it's probably also a good idea to make _regulator_do_enable() robust if it is called on an already enabled rdev. At the moment, _regulator_do_enable() is _not_ robust for already enabled rdevs if we're using an ena_pin. Each time _regulator_do_enable() is called for an rdev using an ena_pin the reference count of the ena_pin is incremented even if the rdev was already enabled. This is not as intended because the ena_pin is for something else: for keeping track of how many active rdevs there are sharing the same ena_pin. Here's how the reference counting works here: * Each time _regulator_enable() is called we increment rdev->use_count, so _regulator_enable() calls need to be balanced with _regulator_disable() calls. * There is no explicit reference counting in _regulator_do_enable() which is normally just a warapper around rdev->desc->ops->enable() with code for supporting delays. It's not expected that the "ops->enable()" call do reference counting. * Since regulator_ena_gpio_ctrl() does have reference counting (handling the sharing of the pin amongst multiple rdevs), we shouldn't call it if the current rdev is already enabled. Note that as part of this we cleanup (remove) the initting of ena_gpio_state in regulator_register(). In _regulator_do_enable(), _regulator_do_disable() and _regulator_is_enabled() is is clear that ena_gpio_state should be the state of whether this particular rdev has requested the GPIO be enabled. regulator_register() was initting it as the actual state of the pin. Fixes: 967cfb18c0e3 ("regulator: core: manage enable GPIO list") Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/regulator/core.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) -- 1.9.1