Messages in this thread | | | Date | Fri, 15 Apr 2016 11:27:51 +0200 | Subject | Re: [PATCH v2] pinctrl: pinctrl-single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs | From | Linus Walleij <> |
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On Thu, Apr 14, 2016 at 6:59 AM, Keerthy <j-keerthy@ti.com> wrote:
> pcs_parse_bits_in_pinctrl_entry uses ffs which gives bit indices > ranging from 1 to MAX. This leads to a corner case where we try to request > the pin number = MAX and fails. > > bit_pos value is being calculted using ffs. pin_num_from_lsb uses > bit_pos value. pins array is populated with: > > pin + pin_num_from_lsb. > > The above is 1 more than usual bit indices as bit_pos uses ffs to compute > first set bit. Hence the last of the pins array is populated with the MAX > value and not MAX - 1 which causes error when we call pin_request. > > mask_pos is rightly calculated as ((pcs->fmask) << (bit_pos - 1)) > Consequently val_pos and submask are correct. > > Hence use __ffs which gives (ffs(x) - 1) as the first bit set. > > fixes: 4e7e8017a8 ("pinctrl: pinctrl-single: enhance to configure multiple pins of different modules") > Signed-off-by: Keerthy <j-keerthy@ti.com> > --- > > Changes in v2: > > * Changed pcs->fshift to use __ffs instead of ffs to be consistent. > > Boot tesed on da850-evm and checked the pinctrl sysfs nodes.
Patch applied for fixes with Tony's ACK.
Should it also be tagged for stable?
Yours, Linus Walleij
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