[PATCH v3 4/6] drm: atmel-hlcdc: enable sys_clk during initalization.

From: Claudiu.Beznea
Date: Thu Apr 25 2019 - 08:28:44 EST


From: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@xxxxxxxxxxxxx>

For SAM9X60 SoC, sys_clk is through lcd_gclk clock source and this
needs to be enabled before enabling lcd_clk.

Signed-off-by: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@xxxxxxxxxxxxx>
[claudiu.beznea@xxxxxxxxxxxxx: add fixed_clksrc checks]
Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
---
drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
index 0be13eceedba..8bf51f853721 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
@@ -625,10 +625,18 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev)
dc->hlcdc = dev_get_drvdata(dev->dev->parent);
dev->dev_private = dc;

+ if (dc->desc->fixed_clksrc) {
+ ret = clk_prepare_enable(dc->hlcdc->sys_clk);
+ if (ret) {
+ dev_err(dev->dev, "failed to enable sys_clk\n");
+ goto err_destroy_wq;
+ }
+ }
+
ret = clk_prepare_enable(dc->hlcdc->periph_clk);
if (ret) {
dev_err(dev->dev, "failed to enable periph_clk\n");
- goto err_destroy_wq;
+ goto err_sys_clk_disable;
}

pm_runtime_enable(dev->dev);
@@ -664,6 +672,9 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev)
err_periph_clk_disable:
pm_runtime_disable(dev->dev);
clk_disable_unprepare(dc->hlcdc->periph_clk);
+err_sys_clk_disable:
+ if (dc->desc->fixed_clksrc)
+ clk_disable_unprepare(dc->hlcdc->sys_clk);

err_destroy_wq:
destroy_workqueue(dc->wq);
@@ -688,6 +699,8 @@ static void atmel_hlcdc_dc_unload(struct drm_device *dev)

pm_runtime_disable(dev->dev);
clk_disable_unprepare(dc->hlcdc->periph_clk);
+ if (dc->desc->fixed_clksrc)
+ clk_disable_unprepare(dc->hlcdc->sys_clk);
destroy_workqueue(dc->wq);
}

@@ -805,6 +818,8 @@ static int atmel_hlcdc_dc_drm_suspend(struct device *dev)
regmap_read(regmap, ATMEL_HLCDC_IMR, &dc->suspend.imr);
regmap_write(regmap, ATMEL_HLCDC_IDR, dc->suspend.imr);
clk_disable_unprepare(dc->hlcdc->periph_clk);
+ if (dc->desc->fixed_clksrc)
+ clk_disable_unprepare(dc->hlcdc->sys_clk);

return 0;
}
@@ -814,6 +829,8 @@ static int atmel_hlcdc_dc_drm_resume(struct device *dev)
struct drm_device *drm_dev = dev_get_drvdata(dev);
struct atmel_hlcdc_dc *dc = drm_dev->dev_private;

+ if (dc->desc->fixed_clksrc)
+ clk_prepare_enable(dc->hlcdc->sys_clk);
clk_prepare_enable(dc->hlcdc->periph_clk);
regmap_write(dc->hlcdc->regmap, ATMEL_HLCDC_IER, dc->suspend.imr);

--
2.7.4