Re: [RFC PATCH] drm/mipi-dsi: add some generic functions for DCS

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

Hi YoungJun, Thierry,

On 07/31/2014 06:14 AM, YoungJun Cho wrote:
> This patch adds some generic functions for DCS like below
> to standize on common APIs rather than per-driver
> implementations.
>
> mipi_dcs_enter_sleep_mode() / mipi_dcs_exit_sleep_mode()
> - These are required to disable / enable all blocks inside
>   the display module.
>
> mipi_dcs_set_display_off() / mipi_dcs_set_display_on()
> - These are required to stop / start displaying the image
>   data on the display device.
>
> mipi_dcs_set_tear_off() / mipi_dcs_set_tear_on()
> - These are required to turn off or on the display module's
>   TE output signal on the TE signal line.

I wonder if it wouldn't be better to make these functions inline.

Regards
Andrzej

>
> mipi_dsi_set_maximum_return_packet_size()
> - Although it is not related with DCS, it is required before
>   using mipi_dsi_dcs_read() to specify the maximum size of
>   the payload in a long packet.
>
> Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
> Acked-by: Inki Dae <inki.dae@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
>  drivers/gpu/drm/drm_mipi_dsi.c | 113 +++++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_mipi_dsi.h     |  14 +++++
>  2 files changed, 127 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
> index 6b2bbda..ba506d7 100644
> --- a/drivers/gpu/drm/drm_mipi_dsi.c
> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
> @@ -269,6 +269,119 @@ ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, unsigned int channel,
>  }
>  EXPORT_SYMBOL(mipi_dsi_dcs_read);
>  
> +/**
> + * mipi_dsi_set_maximum_return_packet_size
> + * - specify the maximum size of the payload in a Long packet transmitted from
> + *   peripheral back to the host processor
> + * @dsi: DSI peripheral device
> + * @size: the maximum size of the payload
> + */
> +int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
> +						u16 size)
> +{
> +	const struct mipi_dsi_host_ops *ops = dsi->host->ops;
> +	struct mipi_dsi_msg msg;
> +
> +	if (!ops || !ops->transfer)
> +		return -ENOSYS;
> +
> +	memset(&msg, 0, sizeof(msg));
> +	msg.channel = dsi->channel;
> +	msg.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE;
> +	msg.tx_len = sizeof(size);
> +	msg.tx_buf = (const void *)(&size);
> +
> +	return ops->transfer(dsi->host, &msg);
> +}
> +EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);
> +
> +/**
> + * mipi_dcs_enter_sleep_mode - disable all unnecessary blocks inside the display
> + *                             module except interface communication
> + * @dsi: DSI peripheral device
> + */
> +int mipi_dcs_enter_sleep_mode(struct mipi_dsi_device *dsi)
> +{
> +	u8 data = MIPI_DCS_ENTER_SLEEP_MODE;
> +
> +	return mipi_dsi_dcs_write(dsi, dsi->channel, (const void *)&data,
> +					sizeof(data));
> +}
> +EXPORT_SYMBOL(mipi_dcs_enter_sleep_mode);
> +
> +/**
> + * mipi_dcs_exit_sleep_mode - enable all blocks inside the display module
> + * @dsi: DSI peripheral device
> + */
> +int mipi_dcs_exit_sleep_mode(struct mipi_dsi_device *dsi)
> +{
> +	u8 data = MIPI_DCS_EXIT_SLEEP_MODE;
> +
> +	return mipi_dsi_dcs_write(dsi, dsi->channel, (const void *)&data,
> +					sizeof(data));
> +}
> +EXPORT_SYMBOL(mipi_dcs_exit_sleep_mode);
> +
> +/**
> + * mipi_dcs_set_display_off - stop displaying the image data on the display device
> + * @dsi: DSI peripheral device
> + */
> +int mipi_dcs_set_display_off(struct mipi_dsi_device *dsi)
> +{
> +	u8 data = MIPI_DCS_SET_DISPLAY_OFF;
> +
> +	return mipi_dsi_dcs_write(dsi, dsi->channel, (const void *)&data,
> +					sizeof(data));
> +}
> +EXPORT_SYMBOL(mipi_dcs_set_display_off);
> +
> +/**
> + * mipi_dcs_set_display_on - start displaying the image data on the display device
> + * @dsi: DSI peripheral device
> + */
> +int mipi_dcs_set_display_on(struct mipi_dsi_device *dsi)
> +{
> +	u8 data = MIPI_DCS_SET_DISPLAY_ON;
> +
> +	return mipi_dsi_dcs_write(dsi, dsi->channel, (const void *)&data,
> +					sizeof(data));
> +}
> +EXPORT_SYMBOL(mipi_dcs_set_display_on);
> +
> +/**
> + * mipi_dcs_set_tear_off - turn off the display module's Tearing Effect output
> + *                         signal on the TE signal line
> + * @dsi: DSI peripheral device
> + */
> +int mipi_dcs_set_tear_off(struct mipi_dsi_device *dsi)
> +{
> +	u8 data = MIPI_DCS_SET_TEAR_OFF;
> +
> +	return mipi_dsi_dcs_write(dsi, dsi->channel, (const void *)&data,
> +					sizeof(data));
> +}
> +EXPORT_SYMBOL(mipi_dcs_set_tear_off);
> +
> +/**
> + * mipi_dcs_set_tear_on - turn on the display module's Tearing Effect output
> + *                        signal on the TE signal line.
> + * @dsi: DSI peripheral device
> + * @mode: the Tearing Effect output line mode
> + *  - MIPI_DCS_TEAR_MODE_VBLANK: the TE output line consists of V-Blanking
> + *                               information only
> + *  - MIPI_DCS_TEAR_MODE_VHBLANK : the TE output line consists of both
> + *                                 V-Blanking and H-Blanking information
> + */
> +int mipi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
> +				enum mipi_dcs_tear_mode mode)
> +{
> +	u8 data[2] = { MIPI_DCS_SET_TEAR_ON, mode };
> +
> +	return mipi_dsi_dcs_write(dsi, dsi->channel, (const void *)data,
> +					sizeof(data));
> +}
> +EXPORT_SYMBOL(mipi_dcs_set_tear_on);
> +
>  static int mipi_dsi_drv_probe(struct device *dev)
>  {
>  	struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
> diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
> index 1c41e49..5af2d0e 100644
> --- a/include/drm/drm_mipi_dsi.h
> +++ b/include/drm/drm_mipi_dsi.h
> @@ -106,6 +106,11 @@ enum mipi_dsi_pixel_format {
>  	MIPI_DSI_FMT_RGB565,
>  };
>  
> +enum mipi_dcs_tear_mode {
> +	MIPI_DCS_TEAR_MODE_VBLANK,
> +	MIPI_DCS_TEAR_MODE_VHBLANK,
> +};
> +
>  /**
>   * struct mipi_dsi_device - DSI peripheral device
>   * @host: DSI host for this peripheral
> @@ -133,6 +138,15 @@ int 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);
> +int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
> +						u16 size);
> +int mipi_dcs_enter_sleep_mode(struct mipi_dsi_device *dsi);
> +int mipi_dcs_exit_sleep_mode(struct mipi_dsi_device *dsi);
> +int mipi_dcs_set_display_off(struct mipi_dsi_device *dsi);
> +int mipi_dcs_set_display_on(struct mipi_dsi_device *dsi);
> +int mipi_dcs_set_tear_off(struct mipi_dsi_device *dsi);
> +int mipi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
> +				enum mipi_dcs_tear_mode mode);
>  
>  /**
>   * struct mipi_dsi_driver - DSI driver