media: cadence: Add operation on reset

Add operation on reset for Cadence MIPI-CSI2 RX Controller.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jack Zhu <jack.zhu@starfivetech.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index 9755d1c..c9b80ac 100644 (file)
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -13,6 +13,7 @@
 #include <linux/of_graph.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 
 #include <media/v4l2-ctrls.h>
@@ -68,6 +69,9 @@ struct csi2rx_priv {
        struct clk                      *sys_clk;
        struct clk                      *p_clk;
        struct clk                      *pixel_clk[CSI2RX_STREAMS_MAX];
+       struct reset_control            *sys_rst;
+       struct reset_control            *p_rst;
+       struct reset_control            *pixel_rst[CSI2RX_STREAMS_MAX];
        struct phy                      *dphy;
 
        u8                              lanes[CSI2RX_LANES_MAX];
@@ -112,6 +116,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
        if (ret)
                return ret;
 
+       reset_control_deassert(csi2rx->p_rst);
        csi2rx_reset(csi2rx);
 
        reg = csi2rx->num_lanes << 8;
@@ -154,6 +159,8 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
                if (ret)
                        goto err_disable_pixclk;
 
+               reset_control_deassert(csi2rx->pixel_rst[i]);
+
                writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF,
                       csi2rx->base + CSI2RX_STREAM_CFG_REG(i));
 
@@ -169,13 +176,16 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
        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--)
+       for (; i > 0; i--) {
+               reset_control_assert(csi2rx->pixel_rst[i - 1]);
                clk_disable_unprepare(csi2rx->pixel_clk[i - 1]);
+       }
 
 err_disable_pclk:
        clk_disable_unprepare(csi2rx->p_clk);
@@ -188,14 +198,17 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
        unsigned int i;
 
        clk_prepare_enable(csi2rx->p_clk);
+       reset_control_assert(csi2rx->sys_rst);
        clk_disable_unprepare(csi2rx->sys_clk);
 
        for (i = 0; i < csi2rx->max_streams; i++) {
                writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(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 (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
@@ -299,6 +312,16 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
                return PTR_ERR(csi2rx->p_clk);
        }
 
+       csi2rx->sys_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
+                                                                   "sys");
+       if (IS_ERR(csi2rx->sys_rst))
+               return PTR_ERR(csi2rx->sys_rst);
+
+       csi2rx->p_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
+                                                                 "reg_bank");
+       if (IS_ERR(csi2rx->p_rst))
+               return PTR_ERR(csi2rx->p_rst);
+
        csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy");
        if (IS_ERR(csi2rx->dphy)) {
                dev_err(&pdev->dev, "Couldn't get external D-PHY\n");
@@ -349,14 +372,21 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
        }
 
        for (i = 0; i < csi2rx->max_streams; i++) {
-               char clk_name[16];
+               char name[16];
 
-               snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i);
-               csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name);
+               snprintf(name, sizeof(name), "pixel_if%u_clk", i);
+               csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, name);
                if (IS_ERR(csi2rx->pixel_clk[i])) {
-                       dev_err(&pdev->dev, "Couldn't get clock %s\n", clk_name);
+                       dev_err(&pdev->dev, "Couldn't get clock %s\n", name);
                        return PTR_ERR(csi2rx->pixel_clk[i]);
                }
+
+               snprintf(name, sizeof(name), "pixel_if%u", i);
+               csi2rx->pixel_rst[i] =
+                       devm_reset_control_get_optional_exclusive(&pdev->dev,
+                                                                 name);
+               if (IS_ERR(csi2rx->pixel_rst[i]))
+                       return PTR_ERR(csi2rx->pixel_rst[i]);
        }
 
        return 0;