@@ -1273,9 +1273,9 @@ static int pcs_parse_bits_in_pinctrl_entry(struct pcs_device *pcs,
/* Parse pins in each row from LSB */
while (mask) {
- bit_pos = ffs(mask);
+ bit_pos = __ffs(mask);
pin_num_from_lsb = bit_pos / pcs->bits_per_pin;
- mask_pos = ((pcs->fmask) << (bit_pos - 1));
+ mask_pos = ((pcs->fmask) << bit_pos);
val_pos = val & mask_pos;
submask = mask & mask_pos;
@@ -1852,7 +1852,7 @@ static int pcs_probe(struct platform_device *pdev)
ret = of_property_read_u32(np, "pinctrl-single,function-mask",
&pcs->fmask);
if (!ret) {
- pcs->fshift = ffs(pcs->fmask) - 1;
+ pcs->fshift = __ffs(pcs->fmask);
pcs->fmax = pcs->fmask >> pcs->fshift;
} else {
/* If mask property doesn't exist, function mux is invalid. */
This is a note to let you know that I have just added a patch titled pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue This patch is scheduled to be released in version 4.2.8-ckt9. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 4.2.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 317d73cda0cc9451fa2ff2224b5ed65f34623a8a Mon Sep 17 00:00:00 2001 From: Keerthy <j-keerthy@ti.com> Date: Thu, 14 Apr 2016 10:29:16 +0530 Subject: pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs commit 56b367c0cd67d4c3006738e7dc9dda9273fd2bfe upstream. 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> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/pinctrl/pinctrl-single.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) -- 2.7.4