[PATCH v3 1/4] clk: qcom: gdsc: Add support to enable/disable the clocks with GDSC

From: Amit Nischal
Date: Mon Aug 13 2018 - 02:33:36 EST


For some of the GDSCs, there is a requirement to enable/disable the
few clocks before turning on/off the gdsc power domain. Add support
for the same by specifying a list of clk_hw pointers per gdsc and
enable/disable them along with power domain on/off callbacks.

Signed-off-by: Amit Nischal <anischal@xxxxxxxxxxxxxx>
---
drivers/clk/qcom/gdsc.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
drivers/clk/qcom/gdsc.h | 5 +++++
2 files changed, 49 insertions(+)

diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c
index a077133..b6adca1 100644
--- a/drivers/clk/qcom/gdsc.c
+++ b/drivers/clk/qcom/gdsc.c
@@ -12,6 +12,8 @@
*/

#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/jiffies.h>
@@ -208,11 +210,41 @@ static inline void gdsc_assert_reset_aon(struct gdsc *sc)
regmap_update_bits(sc->regmap, sc->clamp_io_ctrl,
GMEM_RESET_MASK, 0);
}
+
+static int gdsc_clk_prepare_enable(struct gdsc *sc)
+{
+ int i, ret;
+
+ for (i = 0; i < sc->clk_count; i++) {
+ ret = clk_prepare_enable(sc->clk_hws[i]->clk);
+ if (ret) {
+ for (i--; i >= 0; i--)
+ clk_disable_unprepare(sc->clk_hws[i]->clk);
+ return ret;
+ }
+ }
+ return 0;
+}
+
+static void gdsc_clk_disable_unprepare(struct gdsc *sc)
+{
+ int i;
+
+ for (i = 0; i < sc->clk_count; i++)
+ clk_disable_unprepare(sc->clk_hws[i]->clk);
+}
+
static int gdsc_enable(struct generic_pm_domain *domain)
{
struct gdsc *sc = domain_to_gdsc(domain);
int ret;

+ if (sc->clk_count) {
+ ret = gdsc_clk_prepare_enable(sc);
+ if (ret)
+ return ret;
+ }
+
if (sc->pwrsts == PWRSTS_ON)
return gdsc_deassert_reset(sc);

@@ -260,6 +292,9 @@ static int gdsc_enable(struct generic_pm_domain *domain)
udelay(1);
}

+ if (sc->clk_count)
+ gdsc_clk_disable_unprepare(sc);
+
return 0;
}

@@ -268,6 +303,12 @@ static int gdsc_disable(struct generic_pm_domain *domain)
struct gdsc *sc = domain_to_gdsc(domain);
int ret;

+ if (sc->clk_count) {
+ ret = gdsc_clk_prepare_enable(sc);
+ if (ret)
+ return ret;
+ }
+
if (sc->pwrsts == PWRSTS_ON)
return gdsc_assert_reset(sc);

@@ -299,6 +340,9 @@ static int gdsc_disable(struct generic_pm_domain *domain)
if (sc->flags & CLAMP_IO)
gdsc_assert_clamp_io(sc);

+ if (sc->clk_count)
+ gdsc_clk_disable_unprepare(sc);
+
return 0;
}

diff --git a/drivers/clk/qcom/gdsc.h b/drivers/clk/qcom/gdsc.h
index bd1f2c7..59957d7 100644
--- a/drivers/clk/qcom/gdsc.h
+++ b/drivers/clk/qcom/gdsc.h
@@ -17,6 +17,7 @@
#include <linux/err.h>
#include <linux/pm_domain.h>

+struct clk_hw;
struct regmap;
struct reset_controller_dev;

@@ -32,6 +33,8 @@
* @resets: ids of resets associated with this gdsc
* @reset_count: number of @resets
* @rcdev: reset controller
+ * @clk_count: number of associated clocks
+ * @clk_hws: clk_hw pointers for associated clocks with gdsc
*/
struct gdsc {
struct generic_pm_domain pd;
@@ -60,6 +63,8 @@ struct gdsc {
struct reset_controller_dev *rcdev;
unsigned int *resets;
unsigned int reset_count;
+ unsigned int clk_count;
+ struct clk_hw *clk_hws[];
};

struct gdsc_desc {
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation