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From:   Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
To:     linux-media@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        Luca Ceresoli <luca.ceresoli@bootlin.com>,
        Andy Shevchenko <andriy.shevchenko@intel.com>,
        Matti Vaittinen <Matti.Vaittinen@fi.rohmeurope.com>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>
Cc:     Wolfram Sang <wsa@kernel.org>, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Peter Rosin <peda@axentia.se>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Michael Tretter <m.tretter@pengutronix.de>,
        Hans Verkuil <hverkuil@xs4all.nl>,
        Mike Pagano <mpagano@gentoo.org>,
        =?UTF-8?q?Krzysztof=20Ha=C5=82asa?= <khalasa@piap.pl>,
        Marek Vasut <marex@denx.de>,
        Satish Nagireddy <satish.nagireddy@getcruise.com>,
        Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Subject: [PATCH v14 18/18] media: i2c: ds90ub953: Support non-sync mode
Date:   Fri, 16 Jun 2023 16:59:22 +0300
Message-Id: <20230616135922.442979-19-tomi.valkeinen@ideasonboard.com>
In-Reply-To: <20230616135922.442979-1-tomi.valkeinen@ideasonboard.com>
References: <20230616135922.442979-1-tomi.valkeinen@ideasonboard.com>
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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(-)

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;
-- 
2.34.1