msm: camera: Add mutex protection while dumping registersLA.UM.8.9.r1-05900-SM6xx.0

During LDAR dump, LRME, FD registers are dumped. Due to race
conditions or concurrency, there might be a situation
where the hw is in OFF state and still the registers are
read. This will cause aborts on core.
This commit protects the dumping logic with the hw_mutex for
the two drivers.
Also it fixes one crash scenario while dumping the FD registers.

Change-Id: I9b58b43a005a717b059a1a59d64b1810969004aa
Signed-off-by: Gaurav Jindal <gjindal@codeaurora.org>

2 files changed, 9 insertions, 5 deletions

diff --git a/drivers/media/platform/msm/camera/cam_fd/fd_hw_mgr/fd_hw/cam_fd_hw_core.c b/drivers/media/platform/msm/camera/cam_fd/fd_hw_mgr/fd_hw/cam_fd_hw_core.c
index 20378cad81a6..ef48e9b5e1bc 100644
--- a/drivers/media/platform/msm/camera/cam_fd/fd_hw_mgr/fd_hw/cam_fd_hw_core.c
+++ b/drivers/media/platform/msm/camera/cam_fd/fd_hw_mgr/fd_hw/cam_fd_hw_core.c
@@ -540,7 +540,6 @@ static int cam_fd_hw_util_processcmd_hw_dump(struct cam_hw_info *fd_hw,
 		mutex_unlock(&fd_hw->hw_mutex);
 		return 0;
 	}
-	mutex_unlock(&fd_hw->hw_mutex);
 
 	dump_args = (struct cam_fd_hw_dump_args *)args;
 	soc_info = &fd_hw->soc_info;
@@ -551,6 +550,7 @@ static int cam_fd_hw_util_processcmd_hw_dump(struct cam_hw_info *fd_hw,
 	if (remain_len < min_len) {
 		CAM_ERR(CAM_FD, "dump buffer exhaust %d %d",
 			remain_len, min_len);
+		mutex_unlock(&fd_hw->hw_mutex);
 		return 0;
 	}
 	dst = (char *)dump_args->cpu_addr + dump_args->offset;
@@ -561,14 +561,15 @@ static int cam_fd_hw_util_processcmd_hw_dump(struct cam_hw_info *fd_hw,
 	addr = (uint32_t *)(dst + sizeof(struct cam_fd_hw_dump_header));
 	start = addr;
 	*addr++ = soc_info->index;
-	num_reg = soc_info->reg_map[0].size/4;
 	for (j = 0; j < soc_info->num_reg_map; j++) {
+		num_reg = soc_info->reg_map[j].size/4;
 		for (i = 0; i < num_reg; i++) {
-			*addr++ = soc_info->mem_block[0]->start + i*4;
-			*addr++ = cam_io_r(soc_info->reg_map[i].mem_base +
+			*addr++ = soc_info->mem_block[j]->start + i*4;
+			*addr++ = cam_io_r(soc_info->reg_map[j].mem_base +
 				(i*4));
 		}
 	}
+	mutex_unlock(&fd_hw->hw_mutex);
 	hdr->size = hdr->word_size * (addr - start);
 	dump_args->offset += hdr->size +
 		sizeof(struct cam_fd_hw_dump_header);
diff --git a/drivers/media/platform/msm/camera/cam_lrme/lrme_hw_mgr/lrme_hw/cam_lrme_hw_core.c b/drivers/media/platform/msm/camera/cam_lrme/lrme_hw_mgr/lrme_hw/cam_lrme_hw_core.c
index 880eaa4c20a6..4b6f0b9514ff 100644
--- a/drivers/media/platform/msm/camera/cam_lrme/lrme_hw_mgr/lrme_hw/cam_lrme_hw_core.c
+++ b/drivers/media/platform/msm/camera/cam_lrme/lrme_hw_mgr/lrme_hw/cam_lrme_hw_core.c
@@ -90,7 +90,6 @@ static int cam_lrme_hw_dump(struct cam_hw_info *lrme_hw,
 		mutex_unlock(&lrme_hw->hw_mutex);
 		return 0;
 	}
-	mutex_unlock(&lrme_hw->hw_mutex);
 	if (lrme_core->req_submit &&
 		lrme_core->req_submit->req_id == dump_args->request_id)
 		req = lrme_core->req_submit;
@@ -100,6 +99,7 @@ static int cam_lrme_hw_dump(struct cam_hw_info *lrme_hw,
 	if (!req) {
 		CAM_DBG(CAM_LRME, "LRME req %lld not with hw",
 			dump_args->request_id);
+		mutex_unlock(&lrme_hw->hw_mutex);
 		return 0;
 	}
 	cam_common_util_get_curr_timestamp(&cur_time);
@@ -112,6 +112,7 @@ static int cam_lrme_hw_dump(struct cam_hw_info *lrme_hw,
 			req->submit_timestamp.tv_usec,
 			cur_time.tv_sec,
 			cur_time.tv_usec);
+		mutex_unlock(&lrme_hw->hw_mutex);
 		return 0;
 	}
 	CAM_INFO(CAM_LRME, "Error req %lld %ld:%06ld %ld:%06ld",
@@ -126,6 +127,7 @@ static int cam_lrme_hw_dump(struct cam_hw_info *lrme_hw,
 	if (remain_len < min_len) {
 		CAM_ERR(CAM_LRME, "dump buffer exhaust %d %d",
 			remain_len, min_len);
+		mutex_unlock(&lrme_hw->hw_mutex);
 		return 0;
 	}
 	dst = (char *)dump_args->cpu_addr + dump_args->offset;
@@ -144,6 +146,7 @@ static int cam_lrme_hw_dump(struct cam_hw_info *lrme_hw,
 	dump_args->offset += hdr->size +
 		sizeof(struct cam_lrme_hw_dump_header);
 	cam_lrme_dump_regs_to_buf(req, lrme_hw, dump_args);
+	mutex_unlock(&lrme_hw->hw_mutex);
 	return 0;
 }