[PATCH v2 2/7] drm: rcar-du: lvds: Add runtime PM

[Tomi Valkeinen]

Add simple runtime PM suspend and resume functionality.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen+rene...@ideasonboard.com>
---
 drivers/gpu/drm/rcar-du/rcar_lvds.c | 43 +++++++++++++++++++++++++----
 1 file changed, 37 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c 
b/drivers/gpu/drm/rcar-du/rcar_lvds.c
index 81a060c2fe3f..8e1be51fbee6 100644
--- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
+++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
@@ -16,6 +16,7 @@
 #include <linux/of_device.h>
 #include <linux/of_graph.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/sys_soc.h>
 
@@ -316,8 +317,8 @@ int rcar_lvds_pclk_enable(struct drm_bridge *bridge, 
unsigned long freq)
 
        dev_dbg(lvds->dev, "enabling LVDS PLL, freq=%luHz\n", freq);
 
-       ret = clk_prepare_enable(lvds->clocks.mod);
-       if (ret < 0)
+       ret = pm_runtime_resume_and_get(lvds->dev);
+       if (ret)
                return ret;
 
        __rcar_lvds_pll_setup_d3_e3(lvds, freq, true);
@@ -337,7 +338,7 @@ void rcar_lvds_pclk_disable(struct drm_bridge *bridge)
 
        rcar_lvds_write(lvds, LVDPLLCR, 0);
 
-       clk_disable_unprepare(lvds->clocks.mod);
+       pm_runtime_put(lvds->dev);
 }
 EXPORT_SYMBOL_GPL(rcar_lvds_pclk_disable);
 
@@ -396,8 +397,8 @@ static void __rcar_lvds_atomic_enable(struct drm_bridge 
*bridge,
        u32 lvdcr0;
        int ret;
 
-       ret = clk_prepare_enable(lvds->clocks.mod);
-       if (ret < 0)
+       ret = pm_runtime_resume_and_get(lvds->dev);
+       if (ret)
                return;
 
        /* Enable the companion LVDS encoder in dual-link mode. */
@@ -551,7 +552,7 @@ static void rcar_lvds_atomic_disable(struct drm_bridge 
*bridge,
                lvds->companion->funcs->atomic_disable(lvds->companion,
                                                       old_bridge_state);
 
-       clk_disable_unprepare(lvds->clocks.mod);
+       pm_runtime_put(lvds->dev);
 }
 
 static bool rcar_lvds_mode_fixup(struct drm_bridge *bridge,
@@ -844,6 +845,8 @@ static int rcar_lvds_probe(struct platform_device *pdev)
        if (ret < 0)
                return ret;
 
+       pm_runtime_enable(&pdev->dev);
+
        drm_bridge_add(&lvds->bridge);
 
        return 0;
@@ -855,6 +858,8 @@ static int rcar_lvds_remove(struct platform_device *pdev)
 
        drm_bridge_remove(&lvds->bridge);
 
+       pm_runtime_disable(&pdev->dev);
+
        return 0;
 }
 
@@ -913,11 +918,37 @@ static const struct of_device_id rcar_lvds_of_table[] = {
 
 MODULE_DEVICE_TABLE(of, rcar_lvds_of_table);
 
+static int rcar_lvds_runtime_suspend(struct device *dev)
+{
+       struct rcar_lvds *lvds = dev_get_drvdata(dev);
+
+       clk_disable_unprepare(lvds->clocks.mod);
+
+       return 0;
+}
+
+static int rcar_lvds_runtime_resume(struct device *dev)
+{
+       struct rcar_lvds *lvds = dev_get_drvdata(dev);
+       int ret;
+
+       ret = clk_prepare_enable(lvds->clocks.mod);
+       if (ret < 0)
+               return ret;
+
+       return 0;
+}
+
+static const struct dev_pm_ops rcar_lvds_pm_ops = {
+       SET_RUNTIME_PM_OPS(rcar_lvds_runtime_suspend, rcar_lvds_runtime_resume, 
NULL)
+};
+
 static struct platform_driver rcar_lvds_platform_driver = {
        .probe          = rcar_lvds_probe,
        .remove         = rcar_lvds_remove,
        .driver         = {
                .name   = "rcar-lvds",
+               .pm     = &rcar_lvds_pm_ops,
                .of_match_table = rcar_lvds_of_table,
        },
 };
-- 
2.34.1