[PATCH] pinctrl: mt7622: fix probe fail by misuse the selector

[PATCH] pinctrl: mt7622: fix probe fail by misuse the selector

[sean.wang]

From: Sean Wang <sean.wang@mediatek.com>

After the commit acf137951367 ("pinctrl: core: Return selector to the
pinctrl driver") and the commit 47f1242d19c3 ("pinctrl: pinmux: Return
selector to the pinctrl driver"), it's necessary to add the fixes
needed for the pin controller drivers to use the appropriate returned
selector for a negative error number returned in case of the fail at
these functions. Otherwise, the driver would have a failed probe and
that causes boot message cannot correctly output and devices fail
to acquire their own pins.

Cc: Kevin Hilman <khilman@baylibre.com>
Fixes: acf137951367 ("pinctrl: core: Return selector to the pinctrl driver")
Fixes: 47f1242d19c3 ("pinctrl: pinmux: Return selector to the pinctrl driver")
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
 drivers/pinctrl/mediatek/pinctrl-mt7622.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/mediatek/pinctrl-mt7622.c b/drivers/pinctrl/mediatek/pinctrl-mt7622.c
index 2411c384..6f931b8 100644
--- a/drivers/pinctrl/mediatek/pinctrl-mt7622.c
+++ b/drivers/pinctrl/mediatek/pinctrl-mt7622.c
@@ -1538,7 +1538,7 @@ static int mtk_build_groups(struct mtk_pinctrl *hw)
 		err = pinctrl_generic_add_group(hw->pctrl, group->name,
 						group->pins, group->num_pins,
 						group->data);
-		if (err) {
+		if (err < 0) {
 			dev_err(hw->dev, "Failed to register group %s\n",
 				group->name);
 			return err;
@@ -1559,7 +1559,7 @@ static int mtk_build_functions(struct mtk_pinctrl *hw)
 						  func->group_names,
 						  func->num_group_names,
 						  func->data);
-		if (err) {
+		if (err < 0) {
 			dev_err(hw->dev, "Failed to register function %s\n",
 				func->name);
 			return err;
-- 
2.7.4

Re: [PATCH] pinctrl: mt7622: fix probe fail by misuse the selector

[Linus Walleij]

On Thu, Jul 12, 2018 at 7:50 AM <sean.wang@mediatek.com> wrote:

> From: Sean Wang <sean.wang@mediatek.com>
>
> After the commit acf137951367 ("pinctrl: core: Return selector to the
> pinctrl driver") and the commit 47f1242d19c3 ("pinctrl: pinmux: Return
> selector to the pinctrl driver"), it's necessary to add the fixes
> needed for the pin controller drivers to use the appropriate returned
> selector for a negative error number returned in case of the fail at
> these functions. Otherwise, the driver would have a failed probe and
> that causes boot message cannot correctly output and devices fail
> to acquire their own pins.
>
> Cc: Kevin Hilman <khilman@baylibre.com>
> Fixes: acf137951367 ("pinctrl: core: Return selector to the pinctrl driver")
> Fixes: 47f1242d19c3 ("pinctrl: pinmux: Return selector to the pinctrl driver")
> Signed-off-by: Sean Wang <sean.wang@mediatek.com>

Applied on top of Tony's patches on the fixes branch.

Now there are fixes piling on top of fixes and I am starting to feel
insecure of pushing this to v4.18 and I feel like letting these
fixes go to v4.19 (it can be picked to stable from there).

Tony: do you think there could be more fallout like this?

Yours,
Linus Walleij

Re: [PATCH] pinctrl: mt7622: fix probe fail by misuse the selector

[Tony Lindgren]

* Linus Walleij <linus.walleij@linaro.org> [180713 08:14]:
> On Thu, Jul 12, 2018 at 7:50 AM <sean.wang@mediatek.com> wrote:
> 
> > From: Sean Wang <sean.wang@mediatek.com>
> >
> > After the commit acf137951367 ("pinctrl: core: Return selector to the
> > pinctrl driver") and the commit 47f1242d19c3 ("pinctrl: pinmux: Return
> > selector to the pinctrl driver"), it's necessary to add the fixes
> > needed for the pin controller drivers to use the appropriate returned
> > selector for a negative error number returned in case of the fail at
> > these functions. Otherwise, the driver would have a failed probe and
> > that causes boot message cannot correctly output and devices fail
> > to acquire their own pins.
> >
> > Cc: Kevin Hilman <khilman@baylibre.com>
> > Fixes: acf137951367 ("pinctrl: core: Return selector to the pinctrl driver")
> > Fixes: 47f1242d19c3 ("pinctrl: pinmux: Return selector to the pinctrl driver")
> > Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> 
> Applied on top of Tony's patches on the fixes branch.
> 
> Now there are fixes piling on top of fixes and I am starting to feel
> insecure of pushing this to v4.18 and I feel like letting these
> fixes go to v4.19 (it can be picked to stable from there).

Yes might be worth waiting as we're getting close to the merge window.

> Tony: do you think there could be more fallout like this?

Based on grep -A5 pinctrl_generic_add we have also:

drivers/pinctrl/pinctrl-ingenic.c

Looks like it should check for if (err < 0). Adding Paul Cercueil
to Cc as well, Paul can you please check and patch?

Then 12f953b382bf ("pinctrl: rza1: Fix selector use for groups and
functions") seems to have fixed a similar issue for
drivers/pinctrl/pinctrl-rza1.c

Regards,

Tony