Commit e332061b authored by Laurent Pinchart's avatar Laurent Pinchart Committed by Mauro Carvalho Chehab
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media: i2c: max9286: Configure remote I2C speed from device tree 



Read the maxim,i2c-clock-frequency DT property that specifies the speed
of the remote I2C bus, and configure the MAX9286 accordingly. The remote
serializers must all have a matching configuration.

Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: default avatarJacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent cdcb186e

drivers/media/i2c/max9286.c

+47 −9
Original line number Diff line number Diff line
@@ -144,6 +144,11 @@ struct max9286_format_info { 
	u8 datatype;

};



struct max9286_i2c_speed {

	u32 rate;

	u8 mstbt;

};



struct max9286_source {

	struct v4l2_subdev *sd;

	struct fwnode_handle *fwnode;
@@ -177,6 +182,7 @@ struct max9286_priv { 
	/* The initial reverse control channel amplitude. */

	u32 init_rev_chan_mv;

	u32 rev_chan_mv;

	u8 i2c_mstbt;



	bool use_gpio_poc;

	u32 gpio_poc[2];
@@ -254,6 +260,17 @@ static const struct max9286_format_info max9286_formats[] = { 
	},

};



static const struct max9286_i2c_speed max9286_i2c_speeds[] = {

	{ .rate =   8470, .mstbt = MAX9286_I2CMSTBT_8KBPS },

	{ .rate =  28300, .mstbt = MAX9286_I2CMSTBT_28KBPS },

	{ .rate =  84700, .mstbt = MAX9286_I2CMSTBT_84KBPS },

	{ .rate = 105000, .mstbt = MAX9286_I2CMSTBT_105KBPS },

	{ .rate = 173000, .mstbt = MAX9286_I2CMSTBT_173KBPS },

	{ .rate = 339000, .mstbt = MAX9286_I2CMSTBT_339KBPS },

	{ .rate = 533000, .mstbt = MAX9286_I2CMSTBT_533KBPS },

	{ .rate = 837000, .mstbt = MAX9286_I2CMSTBT_837KBPS },

};



/* -----------------------------------------------------------------------------

 * I2C IO

 */
@@ -374,7 +391,7 @@ static int max9286_i2c_mux_init(struct max9286_priv *priv) 
static void max9286_configure_i2c(struct max9286_priv *priv, bool localack)

{

	u8 config = MAX9286_I2CSLVSH_469NS_234NS | MAX9286_I2CSLVTO_1024US |

		    MAX9286_I2CMSTBT_105KBPS;

		    priv->i2c_mstbt;



	if (localack)

		config |= MAX9286_I2CLOCACK;
@@ -1387,6 +1404,8 @@ static int max9286_parse_dt(struct max9286_priv *priv) 
	struct device_node *node = NULL;

	unsigned int i2c_mux_mask = 0;

	u32 reverse_channel_microvolt;

	u32 i2c_clk_freq = 105000;

	unsigned int i;



	/* Balance the of_node_put() performed by of_find_node_by_name(). */

	of_node_get(dev->of_node);
@@ -1477,6 +1496,23 @@ static int max9286_parse_dt(struct max9286_priv *priv) 
	}

	of_node_put(node);



	of_property_read_u32(dev->of_node, "maxim,i2c-remote-bus-hz",

			     &i2c_clk_freq);

	for (i = 0; i < ARRAY_SIZE(max9286_i2c_speeds); ++i) {

		const struct max9286_i2c_speed *speed = &max9286_i2c_speeds[i];



		if (speed->rate == i2c_clk_freq) {

			priv->i2c_mstbt = speed->mstbt;

			break;

		}

	}



	if (i == ARRAY_SIZE(max9286_i2c_speeds)) {

		dev_err(dev, "Invalid %s value %u\n", "maxim,i2c-remote-bus-hz",

			i2c_clk_freq);

		return -EINVAL;

	}



	/*

	 * Parse the initial value of the reverse channel amplitude from

	 * the firmware interface and convert it to millivolts.
@@ -1550,10 +1586,16 @@ static int max9286_probe(struct i2c_client *client) 
	/* GPIO values default to high */

	priv->gpio_state = BIT(0) | BIT(1);



	ret = max9286_parse_dt(priv);

	if (ret)

		goto err_cleanup_dt;



	priv->gpiod_pwdn = devm_gpiod_get_optional(&client->dev, "enable",

						   GPIOD_OUT_HIGH);

	if (IS_ERR(priv->gpiod_pwdn))

		return PTR_ERR(priv->gpiod_pwdn);

	if (IS_ERR(priv->gpiod_pwdn)) {

		ret = PTR_ERR(priv->gpiod_pwdn);

		goto err_cleanup_dt;

	}



	gpiod_set_consumer_name(priv->gpiod_pwdn, "max9286-pwdn");

	gpiod_set_value_cansleep(priv->gpiod_pwdn, 1);
@@ -1580,10 +1622,6 @@ static int max9286_probe(struct i2c_client *client) 
	if (ret)

		goto err_powerdown;



	ret = max9286_parse_dt(priv);

	if (ret)

		goto err_cleanup_dt;



	if (!priv->use_gpio_poc) {

		ret = max9286_get_poc_supplies(priv);

		if (ret)
@@ -1596,10 +1634,10 @@ static int max9286_probe(struct i2c_client *client) 


	return 0;



err_cleanup_dt:

	max9286_cleanup_dt(priv);

err_powerdown:

	gpiod_set_value_cansleep(priv->gpiod_pwdn, 0);

err_cleanup_dt:

	max9286_cleanup_dt(priv);



	return ret;

}