This is a note to let you know that I've just added the patch titled bus: mhi: Fix pm_state conversion to string to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bus-mhi-fix-pm_state-conversion-to-string.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b459a1a4993d2711f8547107174c59a767db2fc8 Author: Paul Davey <paul.davey@xxxxxxxxxxxxxxxxxxx> Date: Tue Mar 1 21:33:00 2022 +0530 bus: mhi: Fix pm_state conversion to string [ Upstream commit 64f93a9a27c1970fa8ee5ffc5a6ae2bda477ec5b ] On big endian architectures the mhi debugfs files which report pm state give "Invalid State" for all states. This is caused by using find_last_bit which takes an unsigned long* while the state is passed in as an enum mhi_pm_state which will be of int size. Fix by using __fls to pass the value of state instead of find_last_bit. Also the current API expects "mhi_pm_state" enumerator as the function argument but the function only works with bitmasks. So as Alex suggested, let's change the argument to u32 to avoid confusion. Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions") Cc: stable@xxxxxxxxxxxxxxx [mani: changed the function argument to u32] Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx> Reviewed-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx> Reviewed-by: Alex Elder <elder@xxxxxxxxxx> Signed-off-by: Paul Davey <paul.davey@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220301160308.107452-3-manivannan.sadhasivam@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index c0187367ae75..d8787aaa176b 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -77,12 +77,14 @@ static const char * const mhi_pm_state_str[] = { [MHI_PM_STATE_LD_ERR_FATAL_DETECT] = "Linkdown or Error Fatal Detect", }; -const char *to_mhi_pm_state_str(enum mhi_pm_state state) +const char *to_mhi_pm_state_str(u32 state) { - unsigned long pm_state = state; - int index = find_last_bit(&pm_state, 32); + int index; - if (index >= ARRAY_SIZE(mhi_pm_state_str)) + if (state) + index = __fls(state); + + if (!state || index >= ARRAY_SIZE(mhi_pm_state_str)) return "Invalid State"; return mhi_pm_state_str[index]; diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h index c02c4d48b744..71f181402be9 100644 --- a/drivers/bus/mhi/core/internal.h +++ b/drivers/bus/mhi/core/internal.h @@ -622,7 +622,7 @@ void mhi_free_bhie_table(struct mhi_controller *mhi_cntrl, enum mhi_pm_state __must_check mhi_tryset_pm_state( struct mhi_controller *mhi_cntrl, enum mhi_pm_state state); -const char *to_mhi_pm_state_str(enum mhi_pm_state state); +const char *to_mhi_pm_state_str(u32 state); int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl, enum dev_st_transition state); void mhi_pm_st_worker(struct work_struct *work);