drm/dsi: Add mipi_dsi_set_maximum_return_packet_size() helper

This function can be used to set the maximum return packet size for a
MIPI DSI peripheral.

Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
[treding: endianess, kerneldoc, return value]
Signed-off-by: Thierry Reding <treding@nvidia.com>
This commit is contained in:
YoungJun Cho 2014-08-05 09:27:15 +02:00 committed by Thierry Reding
parent ed6ff40ee7
commit dbf30b6958
2 changed files with 26 additions and 0 deletions

View file

@ -332,6 +332,30 @@ int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
}
EXPORT_SYMBOL(mipi_dsi_create_packet);
/*
* mipi_dsi_set_maximum_return_packet_size() - specify the maximum size of the
* the payload in a long packet transmitted from the peripheral back to the
* host processor
* @dsi: DSI peripheral device
* @value: the maximum size of the payload
*
* Return: 0 on success or a negative error code on failure.
*/
int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
u16 value)
{
u8 tx[2] = { value & 0xff, value >> 8 };
struct mipi_dsi_msg msg = {
.channel = dsi->channel,
.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE,
.tx_len = sizeof(tx),
.tx_buf = tx,
};
return mipi_dsi_device_transfer(dsi, &msg);
}
EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);
/**
* mipi_dsi_dcs_write_buffer() - transmit a DCS command with payload
* @dsi: DSI peripheral device

View file

@ -153,6 +153,8 @@ static inline struct mipi_dsi_device *to_mipi_dsi_device(struct device *dev)
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_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,