[PATCH V2 2/2] drm/bridge: ti-sn65dsi83: Add TI SN65DSI83 and SN65DSI84 driver

[Frieder Schrempf]

On 22.04.21 00:31, Marek Vasut wrote:
> Add driver for TI SN65DSI83 Single-link DSI to Single-link LVDS bridge
> and TI SN65DSI84 Single-link DSI to Dual-link or 2x Single-link LVDS
> bridge. TI SN65DSI85 is unsupported due to lack of hardware to test on,
> but easy to add.
> 
> The driver operates the chip via I2C bus. Currently the LVDS clock are
> always derived from DSI clock lane, which is the usual mode of operation.
> Support for clock from external oscillator is not implemented, but it is
> easy to add if ever needed. Only RGB888 pixel format is implemented, the
> LVDS666 is not supported, but could be added if needed.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Douglas Anderson <dianders at chromium.org>
> Cc: Jagan Teki <jagan at amarulasolutions.com>
> Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Cc: Linus Walleij <linus.walleij at linaro.org>
> Cc: Philippe Schenker <philippe.schenker at toradex.com>
> Cc: Sam Ravnborg <sam at ravnborg.org>
> Cc: Stephen Boyd <swboyd at chromium.org>
> Cc: Valentin Raevsky <valentin at compulab.co.il>
> To: dri-devel at lists.freedesktop.org
> Tested-by: Loic Poulain <loic.poulain at linaro.org>
> ---
> V2: - Use dev_err_probe()
>      - Set REG_RC_RESET as volatile
>      - Wait for PLL stabilization by polling REG_RC_LVDS_PLL
>      - Use ctx->mode = *adj instead of *mode in sn65dsi83_mode_set
>      - Add tested DSI84 support in dual-link mode
>      - Correctly set VCOM
>      - Fill in missing DSI CHB and LVDS CHB bits from DSI84 and DSI85
>        datasheets, with that all the reserved bits make far more sense
>        as the DSI83 and DSI84 seems to be reduced version of DSI85
> ---
>   drivers/gpu/drm/bridge/Kconfig        |  10 +
>   drivers/gpu/drm/bridge/Makefile       |   1 +
>   drivers/gpu/drm/bridge/ti-sn65dsi83.c | 617 ++++++++++++++++++++++++++
>   3 files changed, 628 insertions(+)
>   create mode 100644 drivers/gpu/drm/bridge/ti-sn65dsi83.c
> 
[...]
> +static int sn65dsi83_probe(struct i2c_client *client,
> +			   const struct i2c_device_id *id)
> +{
> +	struct device *dev = &client->dev;
> +	enum sn65dsi83_model model;
> +	struct sn65dsi83 *ctx;
> +	int ret;
> +
> +	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx)
> +		return -ENOMEM;
> +
> +	ctx->dev = dev;
> +
> +	if (dev->of_node)
> +		model = (enum sn65dsi83_model)of_device_get_match_data(dev);
> +	else
> +		model = id->driver_data;
> +
> +	/* Default to dual-link LVDS on all but DSI83. */
> +	if (model != MODEL_SN65DSI83)
> +		ctx->lvds_dual_link = true;

What if I use the DSI84 with a single link LVDS? I can't see any way to 
configure that right now.

> +
> +	ctx->enable_gpio = devm_gpiod_get(ctx->dev, "enable", GPIOD_OUT_LOW);
> +	if (IS_ERR(ctx->enable_gpio))
> +		return PTR_ERR(ctx->enable_gpio);
> +
> +	ret = sn65dsi83_parse_dt(ctx);
> +	if (ret)
> +		return ret;
> +
> +	ctx->regmap = devm_regmap_init_i2c(client, &sn65dsi83_regmap_config);
> +	if (IS_ERR(ctx->regmap))
> +		return PTR_ERR(ctx->regmap);
> +
> +	dev_set_drvdata(dev, ctx);
> +	i2c_set_clientdata(client, ctx);
> +
> +	ctx->bridge.funcs = &sn65dsi83_funcs;
> +	ctx->bridge.of_node = dev->of_node;
> +	drm_bridge_add(&ctx->bridge);
> +
> +	return 0;
> +}