[PATCH v2 07/15] clk: qcom: gpucc-sm6115: Add runtime PM

[Konrad Dybcio <konrad.dybcio@linaro.org>]

The GPU_CC block on SM6115 is powered by the VDD_CX rail. We need to
ensure that CX is enabled to prevent unwanted power collapse and that
the reference is dropped when unused so that the system can enter a
firmware-managed lower power state.

Enable runtime PM to keep the power flowing only when necessary.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
---
 drivers/clk/qcom/gpucc-sm6115.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/qcom/gpucc-sm6115.c b/drivers/clk/qcom/gpucc-sm6115.c
index 93a50431aef8..b50979ce1cbe 100644
--- a/drivers/clk/qcom/gpucc-sm6115.c
+++ b/drivers/clk/qcom/gpucc-sm6115.c
@@ -8,6 +8,7 @@
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 
 #include <dt-bindings/clock/qcom,sm6115-gpucc.h>
@@ -443,10 +444,21 @@ MODULE_DEVICE_TABLE(of, gpu_cc_sm6115_match_table);
 static int gpu_cc_sm6115_probe(struct platform_device *pdev)
 {
 	struct regmap *regmap;
+	int ret;
+
+	ret = devm_pm_runtime_enable(&pdev->dev);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_resume_and_get(&pdev->dev);
+	if (ret)
+		return ret;
 
 	regmap = qcom_cc_map(pdev, &gpu_cc_sm6115_desc);
-	if (IS_ERR(regmap))
+	if (IS_ERR(regmap)) {
+		pm_runtime_put(&pdev->dev);
 		return PTR_ERR(regmap);
+	}
 
 	clk_alpha_pll_configure(&gpu_cc_pll0, regmap, &gpu_cc_pll0_config);
 	clk_alpha_pll_configure(&gpu_cc_pll1, regmap, &gpu_cc_pll1_config);
@@ -461,7 +473,10 @@ static int gpu_cc_sm6115_probe(struct platform_device *pdev)
 	qcom_branch_set_clk_en(regmap, 0x1078); /* GPU_CC_AHB_CLK */
 	qcom_branch_set_clk_en(regmap, 0x1060); /* GPU_CC_GX_CXO_CLK */
 
-	return qcom_cc_really_probe(pdev, &gpu_cc_sm6115_desc, regmap);
+	ret = qcom_cc_really_probe(pdev, &gpu_cc_sm6115_desc, regmap);
+	pm_runtime_put(&pdev->dev);
+
+	return ret;
 }
 
 static struct platform_driver gpu_cc_sm6115_driver = {

-- 
2.43.0