[RFC 7/8] drm: Add support for pps and compression mode command packet

From: vikas . korjani
Date: Wed Aug 12 2015 - 05:26:57 EST


From: vkorjani <vikas.korjani@xxxxxxxxx>

After enabling DSC we need to send compression mode command packet
and pps data packet, for which 2 new data types are added
07h Compression Mode Data Type Write , short write, 2 parameters
0Ah PPS Long Write (word count determines number of bytes)
This patch adds support to send these packets.

Cc: David Airlie <airlied@xxxxxxxx>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@xxxxxxxxxxxx>
Cc: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-fbdev@xxxxxxxxxxxxxxx

Signed-off-by: vkorjani <vikas.korjani@xxxxxxxxx>
---
drivers/gpu/drm/drm_mipi_dsi.c | 29 +++++++++++++++++++++++++++++
include/drm/drm_mipi_dsi.h | 4 +++-
include/video/mipi_display.h | 3 +++
3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index 2d5ca8ee..cd536d1 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -521,6 +521,35 @@ ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi,
EXPORT_SYMBOL(mipi_dsi_dcs_write_buffer);

/**
+ * mipi_dsi_dsc_pps_write_buffer() - transmit a DSC command with payload
+ * @dsi: DSI peripheral device
+ * @data: buffer containing data to be transmitted
+ * @len: size of transmission buffer
+ *
+ * function will automatically choose the right data type depending on
+ * the command payload length.
+ *
+ * Return: The number of bytes successfully transmitted or a negative error
+ * code on failure.*/
+ssize_t mipi_dsi_dsc_pps_write_buffer(struct mipi_dsi_device *dsi,
+ const void *data, size_t len)
+{
+ struct mipi_dsi_msg msg = {
+ .channel = dsi->channel,
+ .tx_buf = data,
+ .tx_len = len
+ };
+
+ if (len == 0)
+ msg.type = MIPI_DSI_DCS_COMPRESSION_MODE;
+ else
+ msg.type = MIPI_DSI_PPS_LONG_WRITE;
+
+ return mipi_dsi_device_transfer(dsi, &msg);
+}
+EXPORT_SYMBOL(mipi_dsi_dsc_pps_write_buffer);
+
+/**
* mipi_dsi_dcs_write() - send DCS write command
* @dsi: DSI peripheral device
* @cmd: DCS command
diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
index f1d8d0d..2aa5120 100644
--- a/include/drm/drm_mipi_dsi.h
+++ b/include/drm/drm_mipi_dsi.h
@@ -197,7 +197,9 @@ ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi,
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);
+ size_t len);
+ssize_t mipi_dsi_dsc_pps_write_buffer(struct mipi_dsi_device *dsi,
+ const 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);
diff --git a/include/video/mipi_display.h b/include/video/mipi_display.h
index ddcc8ca..880e6e6 100644
--- a/include/video/mipi_display.h
+++ b/include/video/mipi_display.h
@@ -38,6 +38,9 @@ enum {

MIPI_DSI_DCS_READ = 0x06,

+ MIPI_DSI_DCS_COMPRESSION_MODE = 0x07,
+ MIPI_DSI_PPS_LONG_WRITE = 0x0A,
+
MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE = 0x37,

MIPI_DSI_END_OF_TRANSMISSION = 0x08,
--
1.7.9.5

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