From: Thierry Reding treding@nvidia.com
Implement generic read and write commands. Selection of the proper data type for packets is done automatically based on the number of parameters or payload length.
Signed-off-by: Thierry Reding treding@nvidia.com --- Changes in v4: - do not handle protocol-level details in generic read/write
Changes in v3: - use common helper to simplify code
drivers/gpu/drm/drm_mipi_dsi.c | 89 ++++++++++++++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 6 +++ 2 files changed, 95 insertions(+)
diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c index 640cabcd6c1f..aee7962401fd 100644 --- a/drivers/gpu/drm/drm_mipi_dsi.c +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -282,6 +282,95 @@ int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi, EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);
/** + * mipi_dsi_generic_write() - transmit data using a generic write packet + * @dsi: DSI peripheral device + * @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(struct mipi_dsi_device *dsi, const void *payload, + size_t size) +{ + struct mipi_dsi_msg msg = { + .channel = dsi->channel, + .tx_buf = payload, + .tx_len = size + }; + + switch (size) { + case 0: + msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM; + break; + + case 1: + msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM; + break; + + case 2: + msg.type = MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM; + break; + + default: + msg.type = MIPI_DSI_GENERIC_LONG_WRITE; + break; + } + + return mipi_dsi_device_transfer(dsi, &msg); +} +EXPORT_SYMBOL(mipi_dsi_generic_write); + +/** + * mipi_dsi_generic_read() - receive data using a generic read packet + * @dsi: DSI peripheral device + * @params: buffer containing the request parameters + * @num_params: number of request parameters + * @data: buffer in which to return the received data + * @size: size of receive buffer + * + * This function will automatically choose the right data type depending on + * the number of parameters passed in. + * + * Return: The number of bytes successfully read or a negative error code on + * failure. + */ +ssize_t mipi_dsi_generic_read(struct mipi_dsi_device *dsi, const void *params, + size_t num_params, void *data, size_t size) +{ + struct mipi_dsi_msg msg = { + .channel = dsi->channel, + .tx_len = num_params, + .tx_buf = params, + .rx_len = size, + .rx_buf = data + }; + + switch (num_params) { + case 0: + msg.type = MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM; + break; + + case 1: + msg.type = MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM; + break; + + case 2: + msg.type = MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM; + break; + + default: + return -EINVAL; + } + + return mipi_dsi_device_transfer(dsi, &msg); +} +EXPORT_SYMBOL(mipi_dsi_generic_read); + +/** * mipi_dsi_dcs_write_buffer() - transmit a DCS command with payload * @dsi: DSI peripheral device * @data: buffer containing data to be transmitted diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index bab67099872b..7b7bf895e1b2 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -152,6 +152,12 @@ int mipi_dsi_attach(struct mipi_dsi_device *dsi); int mipi_dsi_detach(struct mipi_dsi_device *dsi); int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi, u16 value); + +ssize_t mipi_dsi_generic_write(struct mipi_dsi_device *dsi, 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); + ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi, const void *data, size_t len); ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, u8 cmd,