From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967246AbaFQWGA (ORCPT ); Tue, 17 Jun 2014 18:06:00 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:54760 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965989AbaFQVwK (ORCPT ); Tue, 17 Jun 2014 17:52:10 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Thomas Petazzoni , Jason Cooper , Kamal Mostafa Subject: [PATCH 3.13 070/212] memory: mvebu-devbus: fix the conversion of the bus width Date: Tue, 17 Jun 2014 14:42:44 -0700 Message-Id: <1403041506-13646-71-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1403041506-13646-1-git-send-email-kamal@canonical.com> References: <1403041506-13646-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Petazzoni commit ce965c3d2e68c5325dd5624eb101d70423022fef upstream. According to the Armada 370 and Armada XP datasheets, the part of the Device Bus register that configure the bus width should contain 0 for a 8 bits bus width, and 1 for a 16 bits bus width (other values are unsupported/reserved). However, the current conversion done in the driver to convert from a bus width in bits to the value expected by the register leads to setting the register to 1 for a 8 bits bus, and 2 for a 16 bits bus. This mistake was compensated by a mistake in the existing Device Tree files for Armada 370/XP platforms: they were declaring a 8 bits bus width, while the hardware in fact uses a 16 bits bus width. This commit fixes that by adjusting the conversion logic. This patch fixes a bug that was introduced in 3edad321b1bd2e6c8b5f38146c115c8982438f06 ('drivers: memory: Introduce Marvell EBU Device Bus driver'), which was merged in v3.11. Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397489361-5833-2-git-send-email-thomas.petazzoni@free-electrons.com Fixes: 3edad321b1bd ('drivers: memory: Introduce Marvell EBU Device Bus driver') Acked-by: Ezequiel Garcia Acked-by: Gregory CLEMENT Signed-off-by: Jason Cooper Signed-off-by: Kamal Mostafa --- drivers/memory/mvebu-devbus.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/memory/mvebu-devbus.c b/drivers/memory/mvebu-devbus.c index 110c036..b59a17f 100644 --- a/drivers/memory/mvebu-devbus.c +++ b/drivers/memory/mvebu-devbus.c @@ -108,8 +108,19 @@ static int devbus_set_timing_params(struct devbus *devbus, node->full_name); return err; } - /* Convert bit width to byte width */ - r.bus_width /= 8; + + /* + * The bus width is encoded into the register as 0 for 8 bits, + * and 1 for 16 bits, so we do the necessary conversion here. + */ + if (r.bus_width == 8) + r.bus_width = 0; + else if (r.bus_width == 16) + r.bus_width = 1; + else { + dev_err(devbus->dev, "invalid bus width %d\n", r.bus_width); + return -EINVAL; + } err = get_timing_param_ps(devbus, node, "devbus,badr-skew-ps", &r.badr_skew); -- 1.9.1