[v10,0/9] Fix up and simplify error recovery mechanism

The changes have been tested with error injections of multiple error types (and
all kinds of mixture of them) during runtime, e.g. hibern8 enter/ exit error,
power mode change error and fatal/non-fatal error from IRQ context. During the
test, error injections happen randomly across all contexts, e.g. clk scaling,
clk gate/ungate, runtime suspend/resume and IRQ.

There are a few more fixes to resolve other minor problems based on the main
change, such as LINERESET handling and racing btw error handler and system
suspend/resume/shutdown, but they will be pushed after this series is taken,
due to there are already too many lines in these changes.

Change since v9:
- Fixed compilation warning from option [-Werror=implicit-fallthrough=] in patch "scsi: ufs: Fix a racing problem btw error handler and runtime PM ops"

Change since v8:
- Added one more fix to ufshcd_abort as requested by Stanley Chu

Change since v7:
- Incorporated Asutosh's comments
- Refined patch "scsi: ufs: Recover hba runtime PM error in error handler"

Change since v6:
- Modified change "scsi: ufs-qcom: Fix schedule while atomic error in ufs_qcom_dump_dbg_regs" to "scsi: ufs-qcom: Remove testbus dump in ufs_qcom_dump_dbg_regs"

Change since v5:
- Dropped change "scsi: ufs: Fix imbalanced scsi_block_reqs_cnt caused by ufshcd_hold()" as it is not quite related with this series
- Refined func ufshcd_err_handling_prepare in change "scsi: ufs: Recover hba runtime PM error in error handler"

Change since v4:
- Split the original change "ufs: ufs-qcom: Fix a few BUGs in func ufs_qcom_dump_dbg_regs()" to 2 small changes

Change since v3:
- Split the original change "scsi: ufs: Fix up and simplify error recovery mechanism" into 5 changes

Change since v2:
- Incorporate Bart's comment to change "scsi: ufs: Add checks before setting clk-gating states"
- Revised the commit msg of change "scsi: ufs: Fix up and simplify error recovery mechanism"

Change since v1:
- Fixed a compilation error in case that CONFIG_PM is N


Can Guo (9):
  scsi: ufs: Add checks before setting clk-gating states
  ufs: ufs-qcom: Fix race conditions caused by func
    ufs_qcom_testbus_config
  scsi: ufs-qcom: Remove testbus dump in ufs_qcom_dump_dbg_regs
  scsi: ufs: Add some debug infos to ufshcd_print_host_state
  scsi: ufs: Fix concurrency of error handler and other error recovery
    paths
  scsi: ufs: Recover hba runtime PM error in error handler
  scsi: ufs: Move dumps in IRQ handler to error handler
  scsi: ufs: Fix a racing problem btw error handler and runtime PM ops
  scsi: ufs: Properly release resources if a task is aborted
    successfully

 drivers/scsi/ufs/ufs-qcom.c  |  37 ----
 drivers/scsi/ufs/ufs-sysfs.c |   1 +
 drivers/scsi/ufs/ufshcd.c    | 509 +++++++++++++++++++++++++++----------------
 drivers/scsi/ufs/ufshcd.h    |  14 ++
 4 files changed, 339 insertions(+), 222 deletions(-)