From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:60276 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752470AbcEAW5b (ORCPT ); Sun, 1 May 2016 18:57:31 -0400 Subject: Patch "pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs" has been added to the 4.5-stable tree To: j-keerthy@ti.com, gregkh@linuxfoundation.org, linus.walleij@linaro.org, tony@atomide.com Cc: , From: Date: Sun, 01 May 2016 15:57:27 -0700 Message-ID: <1462143447207128@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs to the 4.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pinctrl-single-fix-pcs_parse_bits_in_pinctrl_entry-to-use-__ffs-than-ffs.patch and it can be found in the queue-4.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 56b367c0cd67d4c3006738e7dc9dda9273fd2bfe Mon Sep 17 00:00:00 2001 From: Keerthy Date: Thu, 14 Apr 2016 10:29:16 +0530 Subject: pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs From: Keerthy 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 Acked-by: Tony Lindgren Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/pinctrl/pinctrl-single.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/pinctrl/pinctrl-single.c +++ b/drivers/pinctrl/pinctrl-single.c @@ -1273,9 +1273,9 @@ static int pcs_parse_bits_in_pinctrl_ent /* 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; @@ -1844,7 +1844,7 @@ static int pcs_probe(struct platform_dev 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. */ Patches currently in stable-queue which might be from j-keerthy@ti.com are queue-4.5/pinctrl-single-fix-pcs_parse_bits_in_pinctrl_entry-to-use-__ffs-than-ffs.patch