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According to Synopsys support channel, each region of HSA, HBP and HFP must
have minimum number of 10 bytes where constant 4 bytes are for HSS or HSE
and 6 bytes are for blanking packet(header + CRC).  Hence, the below table
comes in.

+------------+----------+-------+
| data lanes | min lbcc | bytes |
+------------+----------+-------+
|     1      |    10    |  1*10 |
+------------+----------+-------+
|     2      |    5     |  2*5  |
+------------+----------+-------+
|     3      |    4     |  3*4  |
+------------+----------+-------+
|     4      |    3     |  4*3  |
+------------+----------+-------+

Implement the minimum lbcc numbers to make sure that the values programmed
into DSI_VID_HSA_TIME and DSI_VID_HBP_TIME registers meet the minimum
number requirement.  For DSI_VID_HLINE_TIME register, it seems that the
value programmed should be based on mode->htotal as-is, instead of sum up
HSA, HBP, HFP and HDISPLAY.

This helps the case where Raydium RM67191 DSI panel is connected, since
it's video timing for hsync length is only 2 pixels and without this patch
the programmed value for DSI_VID_HSA_TIME is only 2 with 4 data lanes.
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230821034008.3876938-7-victor.liu@nxp.com