[PATCH v2 01/23] bus: mhi: Fix pm_state conversion to string

From: Manivannan Sadhasivam
Date: Wed Feb 09 2022 - 05:06:18 EST


From: Paul Davey <paul.davey@xxxxxxxxxxxxxxxxxxx>

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.

Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
Signed-off-by: Paul Davey <paul.davey@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Reviewed-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/bus/mhi/core/init.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 046f407dc5d6..0d588b60929e 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -79,10 +79,12 @@ static const char * const mhi_pm_state_str[] = {

const char *to_mhi_pm_state_str(enum mhi_pm_state 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];
@@ -789,7 +791,6 @@ static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
mhi_chan->offload_ch = ch_cfg->offload_channel;
mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
mhi_chan->pre_alloc = ch_cfg->auto_queue;
- mhi_chan->wake_capable = ch_cfg->wake_capable;

/*
* If MHI host allocates buffers, then the channel direction
--
2.25.1