diff mbox series

[v14,18/18] media: i2c: ds90ub953: Support non-sync mode

Message ID 20230616135922.442979-19-tomi.valkeinen@ideasonboard.com
State Accepted
Commit 618aba51c294d553a8c32d40e014de2709247207
Headers show
Series [v14,01/18] dt-bindings: i2c: Add I2C Address Translator (ATR) | expand

Commit Message

Tomi Valkeinen June 16, 2023, 1:59 p.m. UTC 
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>
---
 drivers/media/i2c/ds90ub953.c | 34 ++++++++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 8 deletions(-)

Comments

Tomi Valkeinen June 19, 2023, 9 a.m. UTC | #1 
On 16/06/2023 17:47, Andy Shevchenko wrote:
> On Fri, Jun 16, 2023 at 04:59:22PM +0300, Tomi Valkeinen wrote:
>> 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.
> 
> ...
> 
>> +	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;
> 
> Redundant 'else'.

True, but I like the symmetry in:

if (foo)
	return 123;
else
	return 321;

> Do I understand correctly you don't want to fallthrough because it will give
> ±160 in the rate (depending if it's even or odd)?

Sorry, can you clarify? Fallthrough to what?

>> +	case UB953_MODE_NONSYNC_EXT:
>> +		/* CLKIN_DIV = 1 always */
>> +		return clk_get_rate(priv->clkin) * 80ull;
>> +
>> +	default:
>>   		/* Not supported */
>>   		return 0;
>>   	}
>
diff mbox series

Patch

diff --git a/drivers/media/i2c/ds90ub953.c b/drivers/media/i2c/ds90ub953.c
index ff55740965eb..ae90a647489a 100644
--- a/drivers/media/i2c/ds90ub953.c
+++ b/drivers/media/i2c/ds90ub953.c
@@ -143,6 +143,7 @@  struct ub953_data {
 
 	struct i2c_client	*client;
 	struct regmap		*regmap;
+	struct clk		*clkin;
 
 	u32			num_data_lanes;
 	bool			non_cont_clk;
@@ -842,15 +843,21 @@  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,
@@ -1189,9 +1196,15 @@  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: %d\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)
@@ -1319,6 +1332,11 @@  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))
+		return dev_err_probe(dev, PTR_ERR(priv->clkin),
+				     "failed to parse 'clkin'\n");
+
 	ret = ub953_parse_dt(priv);
 	if (ret)
 		goto err_mutex_destroy;