[PATCH v4 1/2] bus: mhi: Fix pm_state conversion to string

[Paul Davey <paul.davey@alliedtelesis.co.nz>]

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")
Cc: stable@vger.kernel.org
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>
---
 drivers/bus/mhi/core/init.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 5aaca6d0f52b..0d588b60929e 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -79,9 +79,12 @@ static const char * const mhi_pm_state_str[] = {
 
 const char *to_mhi_pm_state_str(enum mhi_pm_state state)
 {
-	int index = find_last_bit((unsigned long *)&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];
-- 
2.32.0