media: i2c: ds90ub953: Support non-sync mode

Add support for FPD-Link non-sync mode with external clock. The only
thing that needs to be added is the calculation for the clkout.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

diff --git a/drivers/media/i2c/ds90ub953.c b/drivers/media/i2c/ds90ub953.c
index e1bd33e..d56c1dd 100644 (file)
--- a/drivers/media/i2c/ds90ub953.c
+++ b/drivers/media/i2c/ds90ub953.c
@@ -145,6 +145,7 @@ struct ub953_data {
 
        struct i2c_client       *client;
        struct regmap           *regmap;
+       struct clk              *clkin;
 
        u32                     num_data_lanes;
        bool                    non_continous_clk;
@@ -844,15 +845,21 @@ static int ub953_i2c_master_init(struct ub953_data *priv)
 
 static u64 ub953_get_fc_rate(struct ub953_data *priv)
 {
-       if (priv->mode != UB953_MODE_SYNC) {
+       switch (priv->mode) {
+       case UB953_MODE_SYNC:
+               if (priv->hw_data->is_ub971)
+                       return priv->plat_data->bc_rate * 160ull;
+               else
+                       return priv->plat_data->bc_rate / 2 * 160ull;
+
+       case UB953_MODE_NONSYNC_EXT:
+               /* CLKIN_DIV = 1 always */
+               return clk_get_rate(priv->clkin) * 80ull;
+
+       default:
                /* Not supported */
                return 0;
        }
-
-       if (priv->hw_data->is_ub971)
-               return priv->plat_data->bc_rate * 160ull;
-       else
-               return priv->plat_data->bc_rate / 2 * 160ull;
 }
 
 static unsigned long ub953_calc_clkout_ub953(struct ub953_data *priv,
@@ -1195,9 +1202,15 @@ static int ub953_hw_init(struct ub953_data *priv)
        dev_dbg(dev, "mode from %s: %#x\n", mode_override ? "reg" : "strap",
                priv->mode);
 
-       if (priv->mode != UB953_MODE_SYNC)
+       if (priv->mode != UB953_MODE_SYNC &&
+           priv->mode != UB953_MODE_NONSYNC_EXT)
                return dev_err_probe(dev, -ENODEV,
-                                    "Only synchronous mode supported\n");
+                                    "Unsupported mode selected: %u\n",
+                                    priv->mode);
+
+       if (priv->mode == UB953_MODE_NONSYNC_EXT && !priv->clkin)
+               return dev_err_probe(dev, -EINVAL,
+                                    "clkin required for non-sync ext mode\n");
 
        ret = ub953_read(priv, UB953_REG_REV_MASK_ID, &v);
        if (ret)
@@ -1314,6 +1327,13 @@ static int ub953_probe(struct i2c_client *client)
                goto err_mutex_destroy;
        }
 
+       priv->clkin = devm_clk_get_optional(dev, "clkin");
+       if (IS_ERR(priv->clkin)) {
+               ret = PTR_ERR(priv->clkin);
+               dev_err_probe(dev, ret, "failed to parse 'clkin'\n");
+               goto err_mutex_destroy;
+       }
+
        ret = ub953_parse_dt(priv);
        if (ret)
                goto err_mutex_destroy;