From patchwork Tue Apr 26 19:54:42 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 615197 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 3qvYlq4hnbz9sBG; Wed, 27 Apr 2016 05:57:27 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1av96q-0007ON-H9; Tue, 26 Apr 2016 19:57:24 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1av94J-0006Ji-4W for kernel-team@lists.ubuntu.com; Tue, 26 Apr 2016 19:54:47 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1av94I-0008GS-Jj; Tue, 26 Apr 2016 19:54:46 +0000 Received: from kamal by fourier with local (Exim 4.86_2) (envelope-from ) id 1av94F-0001UQ-Tm; Tue, 26 Apr 2016 12:54:43 -0700 From: Kamal Mostafa To: Keerthy Subject: [3.19.y-ckt stable] Patch "pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs" has been added to the 3.19.y-ckt tree Date: Tue, 26 Apr 2016 12:54:42 -0700 Message-Id: <1461700482-5691-1-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 X-Extended-Stable: 3.19 Cc: Tony Lindgren , Linus Walleij , Kamal Mostafa , kernel-team@lists.ubuntu.com X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 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-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt20. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 1cd6c04c227847bcb6d4bb5238abe7413860dc82 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 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: Kamal Mostafa --- drivers/pinctrl/pinctrl-single.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) -- 2.7.4 diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c index 772f7c4..64ac7b1 100644 --- a/drivers/pinctrl/pinctrl-single.c +++ b/drivers/pinctrl/pinctrl-single.c @@ -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; @@ -1851,7 +1851,7 @@ 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. */