media: cadence: csi2rx: Support runtime PM

Use runtime power management hooks to save power when CSI-RX is not in
use. Also, shift to goto based error handling in
csi2rx_enable_streams() function

Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
Tested-by: Rishikesh Donadkar <r-donadkar@ti.com>
Reviewed-by: Rishikesh Donadkar <r-donadkar@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Jai Luthra <jai.luthra@ideasonboard.com>
Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

diff --git a/drivers/media/platform/cadence/Kconfig b/drivers/media/platform/cadence/Kconfig
index 1aa608c00dbce9b52d0d48b5ac8c877db7494fd7..ea85ef82760e694c1e03fa323fc7a468b135e2e1 100644 (file)
--- a/drivers/media/platform/cadence/Kconfig
+++ b/drivers/media/platform/cadence/Kconfig
@@ -5,6 +5,7 @@ comment "Cadence media platform drivers"
 config VIDEO_CADENCE_CSI2RX
        tristate "Cadence MIPI-CSI2 RX Controller"
        depends on VIDEO_DEV
+       depends on PM
        select MEDIA_CONTROLLER
        select VIDEO_V4L2_SUBDEV_API
        select V4L2_FWNODE

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index 8931e824c597c17120879760158164b8b69b179f..1ff2d8f78d5b4c2d6b858298cc087dca64a63025 100644 (file)
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -340,11 +340,6 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
        u32 reg;
        int ret;
 
-       ret = clk_prepare_enable(csi2rx->p_clk);
-       if (ret)
-               return ret;
-
-       reset_control_deassert(csi2rx->p_rst);
        csi2rx_reset(csi2rx);
 
        if (csi2rx->error_irq >= 0)
@@ -385,7 +380,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
                if (ret) {
                        dev_err(csi2rx->dev,
                                "Failed to configure external DPHY: %d\n", ret);
-                       goto err_disable_pclk;
+                       return ret;
                }
        }
 
@@ -400,12 +395,6 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
         * hence the reference counting.
         */
        for (i = 0; i < csi2rx->max_streams; i++) {
-               ret = clk_prepare_enable(csi2rx->pixel_clk[i]);
-               if (ret)
-                       goto err_disable_pixclk;
-
-               reset_control_deassert(csi2rx->pixel_rst[i]);
-
                writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF |
                               FIELD_PREP(CSI2RX_STREAM_CFG_NUM_PIXELS_MASK,
                                          csi2rx->num_pixels[i]),
@@ -418,30 +407,8 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
                       csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
        }
 
-       ret = clk_prepare_enable(csi2rx->sys_clk);
-       if (ret)
-               goto err_disable_pixclk;
-
-       reset_control_deassert(csi2rx->sys_rst);
-
-       clk_disable_unprepare(csi2rx->p_clk);
 
        return 0;
-
-err_disable_pixclk:
-       for (; i > 0; i--) {
-               reset_control_assert(csi2rx->pixel_rst[i - 1]);
-               clk_disable_unprepare(csi2rx->pixel_clk[i - 1]);
-       }
-
-       if (csi2rx->dphy) {
-               writel(0, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
-               phy_power_off(csi2rx->dphy);
-       }
-err_disable_pclk:
-       clk_disable_unprepare(csi2rx->p_clk);
-
-       return ret;
 }
 
 static void csi2rx_stop(struct csi2rx_priv *csi2rx)
@@ -450,10 +417,6 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
        u32 val;
        int ret;
 
-       clk_prepare_enable(csi2rx->p_clk);
-       reset_control_assert(csi2rx->sys_rst);
-       clk_disable_unprepare(csi2rx->sys_clk);
-
        writel(0, csi2rx->base + CSI2RX_ERROR_IRQS_MASK_REG);
 
        for (i = 0; i < csi2rx->max_streams; i++) {
@@ -468,14 +431,8 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
                if (ret)
                        dev_warn(csi2rx->dev,
                                 "Failed to stop streaming on pad%u\n", i);
-
-               reset_control_assert(csi2rx->pixel_rst[i]);
-               clk_disable_unprepare(csi2rx->pixel_clk[i]);
        }
 
-       reset_control_assert(csi2rx->p_rst);
-       clk_disable_unprepare(csi2rx->p_clk);
-
        if (csi2rx->dphy) {
                writel(0, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
 
@@ -549,10 +506,15 @@ static int csi2rx_enable_streams(struct v4l2_subdev *subdev,
         * enable the whole controller.
         */
        if (!csi2rx->count) {
+               ret = pm_runtime_resume_and_get(csi2rx->dev);
+               if (ret < 0)
+                       goto err;
+
                csi2rx_update_vc_select(csi2rx, state);
+
                ret = csi2rx_start(csi2rx);
                if (ret)
-                       return ret;
+                       goto err_put_pm;
        }
 
        /* Start streaming on the source */
@@ -562,13 +524,20 @@ static int csi2rx_enable_streams(struct v4l2_subdev *subdev,
                dev_err(csi2rx->dev,
                        "Failed to start streams %#llx on subdev\n",
                        sink_streams);
-               if (!csi2rx->count)
-                       csi2rx_stop(csi2rx);
-               return ret;
+               goto err_stop_csi;
        }
 
        csi2rx->count++;
        return 0;
+
+err_stop_csi:
+       if (!csi2rx->count)
+               csi2rx_stop(csi2rx);
+err_put_pm:
+       if (!csi2rx->count)
+               pm_runtime_put(csi2rx->dev);
+err:
+       return ret;
 }
 
 static int csi2rx_disable_streams(struct v4l2_subdev *subdev,
@@ -590,8 +559,10 @@ static int csi2rx_disable_streams(struct v4l2_subdev *subdev,
        csi2rx->count--;
 
        /* Let the last user turn off the lights. */
-       if (!csi2rx->count)
+       if (!csi2rx->count) {
                csi2rx_stop(csi2rx);
+               pm_runtime_put(csi2rx->dev);
+       }
 
        return 0;
 }
@@ -1019,6 +990,7 @@ static int csi2rx_probe(struct platform_device *pdev)
        if (ret)
                goto err_cleanup;
 
+       pm_runtime_enable(csi2rx->dev);
        ret = v4l2_async_register_subdev(&csi2rx->subdev);
        if (ret < 0)
                goto err_free_state;
@@ -1033,6 +1005,7 @@ static int csi2rx_probe(struct platform_device *pdev)
 
 err_free_state:
        v4l2_subdev_cleanup(&csi2rx->subdev);
+       pm_runtime_disable(csi2rx->dev);
 err_cleanup:
        v4l2_async_nf_unregister(&csi2rx->notifier);
        v4l2_async_nf_cleanup(&csi2rx->notifier);
@@ -1051,9 +1024,72 @@ static void csi2rx_remove(struct platform_device *pdev)
        v4l2_async_unregister_subdev(&csi2rx->subdev);
        v4l2_subdev_cleanup(&csi2rx->subdev);
        media_entity_cleanup(&csi2rx->subdev.entity);
+       pm_runtime_disable(csi2rx->dev);
        kfree(csi2rx);
 }
 
+static int csi2rx_runtime_suspend(struct device *dev)
+{
+       struct csi2rx_priv *csi2rx = dev_get_drvdata(dev);
+
+       reset_control_assert(csi2rx->sys_rst);
+       clk_disable_unprepare(csi2rx->sys_clk);
+
+       for (unsigned int i = 0; i < csi2rx->max_streams; i++) {
+               reset_control_assert(csi2rx->pixel_rst[i]);
+               clk_disable_unprepare(csi2rx->pixel_clk[i]);
+       }
+
+       reset_control_assert(csi2rx->p_rst);
+       clk_disable_unprepare(csi2rx->p_clk);
+
+       return 0;
+}
+
+static int csi2rx_runtime_resume(struct device *dev)
+{
+       struct csi2rx_priv *csi2rx = dev_get_drvdata(dev);
+       unsigned int i;
+       int ret;
+
+       ret = clk_prepare_enable(csi2rx->p_clk);
+       if (ret)
+               return ret;
+
+       reset_control_deassert(csi2rx->p_rst);
+
+       for (i = 0; i < csi2rx->max_streams; i++) {
+               ret = clk_prepare_enable(csi2rx->pixel_clk[i]);
+               if (ret)
+                       goto err_disable_pixclk;
+
+               reset_control_deassert(csi2rx->pixel_rst[i]);
+       }
+
+       ret = clk_prepare_enable(csi2rx->sys_clk);
+       if (ret)
+               goto err_disable_pixclk;
+
+       reset_control_deassert(csi2rx->sys_rst);
+
+       return 0;
+
+err_disable_pixclk:
+       while (i--) {
+               reset_control_assert(csi2rx->pixel_rst[i]);
+               clk_disable_unprepare(csi2rx->pixel_clk[i]);
+       }
+
+       reset_control_assert(csi2rx->p_rst);
+       clk_disable_unprepare(csi2rx->p_clk);
+
+       return ret;
+}
+
+static const struct dev_pm_ops csi2rx_pm_ops = {
+       RUNTIME_PM_OPS(csi2rx_runtime_suspend, csi2rx_runtime_resume, NULL)
+};
+
 static const struct of_device_id csi2rx_of_table[] = {
        { .compatible = "starfive,jh7110-csi2rx" },
        { .compatible = "cdns,csi2rx" },
@@ -1068,6 +1104,7 @@ static struct platform_driver csi2rx_driver = {
        .driver = {
                .name           = "cdns-csi2rx",
                .of_match_table = csi2rx_of_table,
+               .pm             = &csi2rx_pm_ops,
        },
 };
 module_platform_driver(csi2rx_driver);