[PATCH 4/7] drm: mipi: add mipi_dsi_generic_write_multi_type()

[Dmitry Baryshkov]

On Mon, Jun 24, 2024 at 03:30:28AM GMT, Caleb Connolly wrote:
> Some panels like the Samsung AMB655X use long write commands for all
> non-standard messages and do not work when trying to use the appropriate
> command type.
> 
> Support these panels by introducing a new helper to send commands of a
> specific type, overriding the normal rules.
> 
> Signed-off-by: Caleb Connolly <caleb at postmarketos.org>
> ---
>  drivers/gpu/drm/drm_mipi_dsi.c | 40 ++++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_mipi_dsi.h     | 16 ++++++++++++++++
>  2 files changed, 56 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
> index a471c46f5ca6..d0fee0498d91 100644
> --- a/drivers/gpu/drm/drm_mipi_dsi.c
> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
> @@ -819,8 +819,48 @@ void mipi_dsi_generic_write_multi(struct mipi_dsi_multi_context *ctx,
>  	}
>  }
>  EXPORT_SYMBOL(mipi_dsi_generic_write_multi);
>  
> +/**
> + * mipi_dsi_generic_write_type() - transmit data using a generic write packet of

This doesn't match the name of the function.

> + * a specific type
> + * @dsi: DSI peripheral device
> + * @type: data type of the packet
> + * @payload: buffer containing the payload
> + * @size: size of payload buffer
> + *
> + * This function will automatically choose the right data type depending on
> + * the payload length.
> + *
> + * Return: The number of bytes transmitted on success or a negative error code
> + * on failure.
> + */
> +ssize_t mipi_dsi_generic_write_multi_type(struct mipi_dsi_multi_context *ctx,
> +					  u8 type, const void *payload, size_t size)

write_type_multi. Or maybe write_raw_multi.

> +{
> +	struct mipi_dsi_device *dsi = ctx->dsi;
> +	struct mipi_dsi_msg msg = {
> +		.channel = dsi->channel,
> +		.tx_buf = payload,
> +		.tx_len = size,
> +		.type = type,
> +	};
> +	ssize_t ret;
> +
> +	if (ctx->accum_err)
> +		return 0;
> +
> +	ret = mipi_dsi_device_transfer(dsi, &msg);
> +	if (ret < 0) {
> +		ctx->accum_err = ret;
> +		dev_err(&dsi->dev, "sending generic data %*ph failed: %zd\n",
> +			(int)size, payload, ret);
> +	}
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(mipi_dsi_generic_write_multi_type);
> +
>  /**
>   * mipi_dsi_generic_read() - receive data using a generic read packet
>   * @dsi: DSI peripheral device
>   * @params: buffer containing the request parameters
> diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
> index 71d121aeef24..a5d949e695d4 100644
> --- a/include/drm/drm_mipi_dsi.h
> +++ b/include/drm/drm_mipi_dsi.h
> @@ -287,8 +287,10 @@ ssize_t mipi_dsi_generic_write(struct mipi_dsi_device *dsi, const void *payload,
>  int mipi_dsi_generic_write_chatty(struct mipi_dsi_device *dsi,
>  				  const void *payload, size_t size);
>  void mipi_dsi_generic_write_multi(struct mipi_dsi_multi_context *ctx,
>  				  const void *payload, size_t size);
> +ssize_t mipi_dsi_generic_write_multi_type(struct mipi_dsi_multi_context *ctx, u8 type,
> +				    const void *payload, size_t size);
>  ssize_t mipi_dsi_generic_read(struct mipi_dsi_device *dsi, const void *params,
>  			      size_t num_params, void *data, size_t size);
>  
>  #define mipi_dsi_msleep(ctx, delay)	\
> @@ -432,8 +434,22 @@ void mipi_dsi_dcs_set_tear_on_multi(struct mipi_dsi_multi_context *ctx,
>  		static const u8 d[] = { cmd, seq };                     \
>  		mipi_dsi_dcs_write_buffer_multi(ctx, d, ARRAY_SIZE(d)); \
>  	} while (0)
>  
> +/**
> + * mipi_dsi_dcs_write_long - transmit a DCS long command with payload
> + * @dsi: DSI peripheral device
> + * @cmd: Commands
> + * @seq: buffer containing data to be transmitted
> + */
> +#define mipi_dsi_dcs_write_long(ctx, cmd, seq...)                          \

foo_multi

> +	do {                                                               \
> +		static const u8 d[] = { cmd, seq };                        \
> +		mipi_dsi_generic_write_multi_type(ctx,                     \
> +						  MIPI_DSI_DCS_LONG_WRITE, \
> +						  d, ARRAY_SIZE(d));       \
> +	} while (0)
> +
>  /**
>   * struct mipi_dsi_driver - DSI driver
>   * @driver: device driver model driver
>   * @probe: callback for device binding
> 
> -- 
> 2.45.0
> 

-- 
With best wishes
Dmitry