Re: [PATCH 2/4] drm/dsi: Use peripheral's channel for DCS commands

[Andrzej Hajda <a.hajda@samsung.com>]

On 07/22/2014 09:12 AM, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
>
> When executing DCS commands, use the channel associated with the DSI
> peripheral rather than one explicitly specified in the function call.
> Devices shouldn't be able to step on each others' toes like this.
>
> Signed-off-by: Thierry Reding <treding@nvidia.com>

There could be a problem with devices associated with more than one channel,
but this is theoretical problem as for now, so:

Acked-by: Andrzej Hajda <a.hajda@samsung.com>

Regards
Andrzej


> ---
>  drivers/gpu/drm/drm_mipi_dsi.c        | 14 ++++++--------
>  drivers/gpu/drm/panel/panel-s6e8aa0.c |  4 ++--
>  include/drm/drm_mipi_dsi.h            |  8 ++++----
>  3 files changed, 12 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
> index 6d2fd2077dae..6aa6a9e95570 100644
> --- a/drivers/gpu/drm/drm_mipi_dsi.c
> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
> @@ -201,16 +201,15 @@ EXPORT_SYMBOL(mipi_dsi_detach);
>  /**
>   * mipi_dsi_dcs_write - send DCS write command
>   * @dsi: DSI device
> - * @channel: virtual channel
>   * @data: pointer to the command followed by parameters
>   * @len: length of @data
>   */
> -ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, unsigned int channel,
> -			   const void *data, size_t len)
> +ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, const void *data,
> +			    size_t len)
>  {
>  	const struct mipi_dsi_host_ops *ops = dsi->host->ops;
>  	struct mipi_dsi_msg msg = {
> -		.channel = channel,
> +		.channel = dsi->channel,
>  		.tx_buf = data,
>  		.tx_len = len
>  	};
> @@ -239,19 +238,18 @@ EXPORT_SYMBOL(mipi_dsi_dcs_write);
>  /**
>   * mipi_dsi_dcs_read - send DCS read request command
>   * @dsi: DSI device
> - * @channel: virtual channel
>   * @cmd: DCS read command
>   * @data: pointer to read buffer
>   * @len: length of @data
>   *
>   * Function returns number of read bytes or error code.
>   */
> -ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, unsigned int channel,
> -			  u8 cmd, void *data, size_t len)
> +ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,
> +			  size_t len)
>  {
>  	const struct mipi_dsi_host_ops *ops = dsi->host->ops;
>  	struct mipi_dsi_msg msg = {
> -		.channel = channel,
> +		.channel = dsi->channel,
>  		.type = MIPI_DSI_DCS_READ,
>  		.tx_buf = &cmd,
>  		.tx_len = 1,
> diff --git a/drivers/gpu/drm/panel/panel-s6e8aa0.c b/drivers/gpu/drm/panel/panel-s6e8aa0.c
> index beb43492b649..5502ef6bc074 100644
> --- a/drivers/gpu/drm/panel/panel-s6e8aa0.c
> +++ b/drivers/gpu/drm/panel/panel-s6e8aa0.c
> @@ -138,7 +138,7 @@ static void s6e8aa0_dcs_write(struct s6e8aa0 *ctx, const void *data, size_t len)
>  	if (ctx->error < 0)
>  		return;
>  
> -	ret = mipi_dsi_dcs_write(dsi, dsi->channel, data, len);
> +	ret = mipi_dsi_dcs_write(dsi, data, len);
>  	if (ret < 0) {
>  		dev_err(ctx->dev, "error %zd writing dcs seq: %*ph\n", ret, len,
>  			data);
> @@ -154,7 +154,7 @@ static int s6e8aa0_dcs_read(struct s6e8aa0 *ctx, u8 cmd, void *data, size_t len)
>  	if (ctx->error < 0)
>  		return ctx->error;
>  
> -	ret = mipi_dsi_dcs_read(dsi, dsi->channel, cmd, data, len);
> +	ret = mipi_dsi_dcs_read(dsi, cmd, data, len);
>  	if (ret < 0) {
>  		dev_err(ctx->dev, "error %d reading dcs seq(%#x)\n", ret, cmd);
>  		ctx->error = ret;
> diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
> index 4b0112781910..7b5e1a9244e1 100644
> --- a/include/drm/drm_mipi_dsi.h
> +++ b/include/drm/drm_mipi_dsi.h
> @@ -127,10 +127,10 @@ struct mipi_dsi_device {
>  
>  int mipi_dsi_attach(struct mipi_dsi_device *dsi);
>  int mipi_dsi_detach(struct mipi_dsi_device *dsi);
> -ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, unsigned int channel,
> -			   const void *data, size_t len);
> -ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, unsigned int channel,
> -			  u8 cmd, void *data, size_t len);
> +ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, const void *data,
> +			    size_t len);
> +ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,
> +			  size_t len);
>  
>  /**
>   * struct mipi_dsi_driver - DSI driver