From: Paul Davey <paul.davey@xxxxxxxxxxxxxxxxxxx> commit 64f93a9a27c1970fa8ee5ffc5a6ae2bda477ec5b upstream. 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> --- drivers/bus/mhi/core/init.c | 10 ++++++---- drivers/bus/mhi/core/internal.h | 2 +- 2 files changed, 7 insertions(+), 5 deletions(-) --- 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_s [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]; --- 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_cont 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); Patches currently in stable-queue which might be from paul.davey@xxxxxxxxxxxxxxxxxxx are queue-5.17/bus-mhi-fix-pm_state-conversion-to-string.patch queue-5.17/bus-mhi-fix-mhi-dma-structure-endianness.patch