Commit 1b771839 authored by Dmitry Baryshkov's avatar Dmitry Baryshkov Committed by Stephen Boyd
Browse files

clk: qcom: gdsc: enable optional power domain support 



On sm8250 dispcc and videocc registers are powered up by the MMCX power
domain. Currently we use a regulator to enable this domain on demand,
however this has some consequences, as genpd code is not reentrant.

Make gdsc code also use pm_runtime calls to ensure that registers are
accessible during the gdsc_enable/gdsc_disable operations.

Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210829154757.784699-6-dmitry.baryshkov@linaro.org


Signed-off-by: default avatarStephen Boyd <sboyd@kernel.org>
parent a91c483b

drivers/clk/qcom/gdsc.c

+48 −3
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/kernel.h>

#include <linux/ktime.h>

#include <linux/pm_domain.h>

#include <linux/pm_runtime.h>

#include <linux/regmap.h>

#include <linux/regulator/consumer.h>

#include <linux/reset-controller.h>
@@ -50,6 +51,22 @@ enum gdsc_status { 
	GDSC_ON

};



static int gdsc_pm_runtime_get(struct gdsc *sc)

{

	if (!sc->dev)

		return 0;



	return pm_runtime_resume_and_get(sc->dev);

}



static int gdsc_pm_runtime_put(struct gdsc *sc)

{

	if (!sc->dev)

		return 0;



	return pm_runtime_put_sync(sc->dev);

}



/* Returns 1 if GDSC status is status, 0 if not, and < 0 on error */

static int gdsc_check_status(struct gdsc *sc, enum gdsc_status status)

{
@@ -232,9 +249,8 @@ static void gdsc_retain_ff_on(struct gdsc *sc) 
	regmap_update_bits(sc->regmap, sc->gdscr, mask, mask);

}



static int gdsc_enable(struct generic_pm_domain *domain)

static int _gdsc_enable(struct gdsc *sc)

{

	struct gdsc *sc = domain_to_gdsc(domain);

	int ret;



	if (sc->pwrsts == PWRSTS_ON)
@@ -290,11 +306,22 @@ static int gdsc_enable(struct generic_pm_domain *domain) 
	return 0;

}



static int gdsc_disable(struct generic_pm_domain *domain)

static int gdsc_enable(struct generic_pm_domain *domain)

{

	struct gdsc *sc = domain_to_gdsc(domain);

	int ret;



	ret = gdsc_pm_runtime_get(sc);

	if (ret)

		return ret;



	return _gdsc_enable(sc);

}



static int _gdsc_disable(struct gdsc *sc)

{

	int ret;



	if (sc->pwrsts == PWRSTS_ON)

		return gdsc_assert_reset(sc);
@@ -329,6 +356,18 @@ static int gdsc_disable(struct generic_pm_domain *domain) 
	return 0;

}



static int gdsc_disable(struct generic_pm_domain *domain)

{

	struct gdsc *sc = domain_to_gdsc(domain);

	int ret;



	ret = _gdsc_disable(sc);



	gdsc_pm_runtime_put(sc);



	return ret;

}



static int gdsc_init(struct gdsc *sc)

{

	u32 mask, val;
@@ -443,6 +482,8 @@ int gdsc_register(struct gdsc_desc *desc, 
	for (i = 0; i < num; i++) {

		if (!scs[i])

			continue;

		if (pm_runtime_enabled(dev))

			scs[i]->dev = dev;

		scs[i]->regmap = regmap;

		scs[i]->rcdev = rcdev;

		ret = gdsc_init(scs[i]);
@@ -457,6 +498,8 @@ int gdsc_register(struct gdsc_desc *desc, 
			continue;

		if (scs[i]->parent)

			pm_genpd_add_subdomain(scs[i]->parent, &scs[i]->pd);

		else if (!IS_ERR_OR_NULL(dev->pm_domain))

			pm_genpd_add_subdomain(pd_to_genpd(dev->pm_domain), &scs[i]->pd);

	}



	return of_genpd_add_provider_onecell(dev->of_node, data);
@@ -475,6 +518,8 @@ void gdsc_unregister(struct gdsc_desc *desc) 
			continue;

		if (scs[i]->parent)

			pm_genpd_remove_subdomain(scs[i]->parent, &scs[i]->pd);

		else if (!IS_ERR_OR_NULL(dev->pm_domain))

			pm_genpd_remove_subdomain(pd_to_genpd(dev->pm_domain), &scs[i]->pd);

	}

	of_genpd_del_provider(dev->of_node);

}

drivers/clk/qcom/gdsc.h

+2 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ struct reset_controller_dev; 
 * @resets: ids of resets associated with this gdsc

 * @reset_count: number of @resets

 * @rcdev: reset controller

 * @dev: the device holding the GDSC, used for pm_runtime calls

 */

struct gdsc {

	struct generic_pm_domain	pd;
@@ -58,6 +59,7 @@ struct gdsc { 


	const char 			*supply;

	struct regulator		*rsupply;

	struct device			*dev;

};



struct gdsc_desc {