[PATCH 0/2] drm/msm/dsi: Fix issues during cmd rx

[PATCH 0/2] drm/msm/dsi: Fix issues during cmd rx

[Hai Li]

These 2 patches are to fix the issues during DSI command rx.

Hai Li (2):
  drm/msm/dsi: Fixup missing *break* statement during cmd rx
  drm/msm/dsi: Simplify the code to get the number of read byte

 drivers/gpu/drm/msm/dsi/dsi_host.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

-- 
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[PATCH 1/2] drm/msm/dsi: Fixup missing *break* statement during cmd rx

[Hai Li]

Signed-off-by: Hai Li <hali@codeaurora.org>
---
 drivers/gpu/drm/msm/dsi/dsi_host.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index fdc54e3..473d417 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1797,6 +1797,7 @@ int msm_dsi_host_cmd_rx(struct mipi_dsi_host *host,
 	case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
 		pr_err("%s: rx ACK_ERR_PACLAGE\n", __func__);
 		ret = 0;
+		break;
 	case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
 		ret = dsi_short_read1_resp(buf, msg);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation

[PATCH 2/2] drm/msm/dsi: Simplify the code to get the number of read byte

[Hai Li]

During cmd rx, only new versions of H/W provide register to read back
the real number of byte returned by panel. For the old versions, reading
this register will not get the right number. In fact, we only need to
assume the returned data is the same size as we expected, because later
we will check the data type to detect error.

Signed-off-by: Hai Li <hali@codeaurora.org>
---
 drivers/gpu/drm/msm/dsi/dsi_host.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 473d417..72d4d5f 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1093,7 +1093,6 @@ static int dsi_cmd_dma_rx(struct msm_dsi_host *msm_host,
 {
 	u32 *lp, *temp, data;
 	int i, j = 0, cnt;
-	bool ack_error = false;
 	u32 read_cnt;
 	u8 reg[16];
 	int repeated_bytes = 0;
@@ -1105,15 +1104,10 @@ static int dsi_cmd_dma_rx(struct msm_dsi_host *msm_host,
 	if (cnt > 4)
 		cnt = 4; /* 4 x 32 bits registers only */
 
-	/* Calculate real read data count */
-	read_cnt = dsi_read(msm_host, 0x1d4) >> 16;
-
-	ack_error = (rx_byte == 4) ?
-		(read_cnt == 8) : /* short pkt + 4-byte error pkt */
-		(read_cnt == (pkt_size + 6 + 4)); /* long pkt+4-byte error pkt*/
-
-	if (ack_error)
-		read_cnt -= 4; /* Remove 4 byte error pkt */
+	if (rx_byte == 4)
+		read_cnt = 4;
+	else
+		read_cnt = pkt_size + 6;
 
 	/*
 	 * In case of multiple reads from the panel, after the first read, there
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation