Commit ffc23a20 authored by Brigham Campbell's avatar Brigham Campbell Committed by Douglas Anderson
Browse files

drm: Add MIPI read_multi func and two write macros 



Create mipi_dsi_dcs_read_multi(), which accepts a mipi_dsi_multi_context
struct for improved error handling and cleaner panel driver code.

Create mipi_dsi_dcs_write_var_seq_multi() and
mipi_dsi_generic_write_var_seq_multi() macros which allow MIPI panel
drivers to write non-constant data to display controllers.

Reviewed-by: default avatarDouglas Anderson <dianders@chromium.org>
Signed-off-by: default avatarBrigham Campbell <me@brighamcampbell.com>
Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20250731032343.1258366-3-me@brighamcampbell.com
parent 00708510

drivers/gpu/drm/drm_mipi_dsi.c

+37 −0
Original line number Diff line number Diff line
@@ -1096,6 +1096,43 @@ ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data, 
}

EXPORT_SYMBOL(mipi_dsi_dcs_read);



/**

 * mipi_dsi_dcs_read_multi() - mipi_dsi_dcs_read() w/ accum_err

 * @ctx: Context for multiple DSI transactions

 * @cmd: DCS command

 * @data: buffer in which to receive data

 * @len: size of receive buffer

 *

 * Like mipi_dsi_dcs_read() but deals with errors in a way that makes it

 * convenient to make several calls in a row.

 */

void mipi_dsi_dcs_read_multi(struct mipi_dsi_multi_context *ctx, u8 cmd,

			     void *data, size_t len)

{

	struct mipi_dsi_device *dsi = ctx->dsi;

	struct device *dev = &dsi->dev;

	struct mipi_dsi_msg msg = {

		.channel = dsi->channel,

		.type = MIPI_DSI_DCS_READ,

		.tx_buf = &cmd,

		.tx_len = 1,

		.rx_buf = data,

		.rx_len = len

	};

	ssize_t ret;



	if (ctx->accum_err)

		return;



	ret = mipi_dsi_device_transfer(dsi, &msg);

	if (ret < 0) {

		ctx->accum_err = ret;

		dev_err(dev, "dcs read with command %#x failed: %d\n", cmd,

			ctx->accum_err);

	}

}

EXPORT_SYMBOL(mipi_dsi_dcs_read_multi);



/**

 * mipi_dsi_dcs_nop() - send DCS nop packet

 * @dsi: DSI peripheral device

include/drm/drm_mipi_dsi.h

+35 −0
Original line number Diff line number Diff line
@@ -342,6 +342,8 @@ ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, u8 cmd, 
			   const void *data, size_t len);

ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,

			  size_t len);

void mipi_dsi_dcs_read_multi(struct mipi_dsi_multi_context *ctx, u8 cmd,

			     void *data, size_t len);

int mipi_dsi_dcs_nop(struct mipi_dsi_device *dsi);

int mipi_dsi_dcs_soft_reset(struct mipi_dsi_device *dsi);

int mipi_dsi_dcs_get_power_mode(struct mipi_dsi_device *dsi, u8 *mode);
@@ -403,6 +405,22 @@ void mipi_dsi_dcs_set_tear_off_multi(struct mipi_dsi_multi_context *ctx); 
		mipi_dsi_generic_write_multi(ctx, d, ARRAY_SIZE(d)); \

	} while (0)



/**

 * mipi_dsi_generic_write_var_seq_multi - transmit non-constant data using a

 * generic write packet

 *

 * This macro will print errors for you and error handling is optimized for

 * callers that call this multiple times in a row.

 *

 * @ctx: Context for multiple DSI transactions

 * @seq: buffer containing the payload

 */

#define mipi_dsi_generic_write_var_seq_multi(ctx, seq...)	     \

	do {							     \

		const u8 d[] = { seq };				     \

		mipi_dsi_generic_write_multi(ctx, d, ARRAY_SIZE(d)); \

	} while (0)



/**

 * mipi_dsi_dcs_write_seq_multi - transmit a DCS command with payload

 *
@@ -419,6 +437,23 @@ void mipi_dsi_dcs_set_tear_off_multi(struct mipi_dsi_multi_context *ctx); 
		mipi_dsi_dcs_write_buffer_multi(ctx, d, ARRAY_SIZE(d)); \

	} while (0)



/**

 * mipi_dsi_dcs_write_var_seq_multi - transmit a DCS command with non-constant

 * payload

 *

 * This macro will print errors for you and error handling is optimized for

 * callers that call this multiple times in a row.

 *

 * @ctx: Context for multiple DSI transactions

 * @cmd: Command

 * @seq: buffer containing data to be transmitted

 */

#define mipi_dsi_dcs_write_var_seq_multi(ctx, cmd, seq...)		\

	do {								\

		const u8 d[] = { cmd, seq };				\

		mipi_dsi_dcs_write_buffer_multi(ctx, d, ARRAY_SIZE(d));	\

	} while (0)



/**

 * mipi_dsi_dual - send the same MIPI DSI command to two interfaces

 *