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media: i2c: max9286: Configure remote I2C speed from device tree

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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: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
This commit is contained in:
Laurent Pinchart 2022-01-01 19:28:04 +01:00 committed by Mauro Carvalho Chehab
parent cdcb186e36
commit e332061bbe
1 changed files with 47 additions and 9 deletions
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56
drivers/media/i2c/max9286.c
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@ -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 @@ error:
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;
}