Merge "clk: qcom: gdsc-regulator: Remove regulator_lock() call from GDSC driver" (b785a983) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/clk/qcom/gdsc-regulator.c

+27 −21

Original line number	Diff line number	Diff line
		@@ -344,20 +344,27 @@ static int gdsc_enable(struct regulator_dev *rdev)
		static int gdsc_disable(struct regulator_dev *rdev)
		{
		struct gdsc *sc = rdev_get_drvdata(rdev);
		struct regulator_dev *parent_rdev;
		uint32_t regval;
		int i, ret = 0, parent_enabled;
		int i, ret = 0;
		bool lock = false;

		if (rdev->supply) {
		regulator_lock(rdev->supply->rdev);
		parent_enabled = regulator_is_enabled(rdev->supply);
		if (parent_enabled < 0) {
		ret = parent_enabled;
		dev_err(&rdev->dev, "%s unable to check parent enable state, ret=%d\n",
		sc->rdesc.name, ret);
		goto done;
		}
		parent_rdev = rdev->supply->rdev;

		/*
		* At this point, it can be assumed that parent supply's mutex is always
		* locked by regulator framework before calling this callback but there
		* are code paths where it isn't locked (e.g regulator_late_cleanup()).
		*
		* If parent supply is not locked, lock the parent supply mutex before
		* checking it's enable count, so it won't get disabled while in the
		* middle of GDSC operations
		*/
		if (ww_mutex_trylock(&parent_rdev->mutex))
		lock = true;

		if (!parent_enabled) {
		if (!parent_rdev->use_count) {
		dev_err(&rdev->dev, "%s cannot disable GDSC while parent is disabled\n",
		sc->rdesc.name);
		ret = -EIO;
		@@ -435,8 +442,8 @@ static int gdsc_disable(struct regulator_dev *rdev)
		sc->is_gdsc_enabled = false;

		done:
		if (rdev->supply)
		regulator_unlock(rdev->supply->rdev);
		if (rdev->supply && lock)
		ww_mutex_unlock(&parent_rdev->mutex);

		return ret;
		}
		@@ -466,10 +473,12 @@ static unsigned int gdsc_get_mode(struct regulator_dev *rdev)
		static int gdsc_set_mode(struct regulator_dev *rdev, unsigned int mode)
		{
		struct gdsc *sc = rdev_get_drvdata(rdev);
		struct regulator_dev *parent_rdev;
		uint32_t regval;
		int ret = 0;

		if (rdev->supply) {
		parent_rdev = rdev->supply->rdev;
		/*
		* Ensure that the GDSC parent supply is enabled before
		* continuing. This is needed to avoid an unclocked access
		@@ -479,15 +488,12 @@ static int gdsc_set_mode(struct regulator_dev *rdev, unsigned int mode)
		* state cannot change after checking due to a race with another
		* consumer.
		*/
		regulator_lock(rdev->supply->rdev);
		ret = regulator_is_enabled(rdev->supply);
		if (ret < 0) {
		dev_err(&rdev->dev, "%s unable to check parent enable state, ret=%d\n",
		sc->rdesc.name, ret);
		goto done;
		} else if (WARN(!ret,
		ww_mutex_lock(&parent_rdev->mutex, NULL);

		if (!parent_rdev->use_count) {
		dev_err(&rdev->dev,
		"%s cannot change GDSC HW/SW control mode while parent is disabled\n",
		sc->rdesc.name)) {
		sc->rdesc.name);
		ret = -EIO;
		goto done;
		}
		@@ -554,7 +560,7 @@ static int gdsc_set_mode(struct regulator_dev *rdev, unsigned int mode)

		done:
		if (rdev->supply)
		regulator_unlock(rdev->supply->rdev);
		ww_mutex_unlock(&parent_rdev->mutex);

		return ret;
		}