From patchwork Thu May 8 23:20:34 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Fenkart X-Patchwork-Id: 4139491 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 80B649F1E1 for ; Thu, 8 May 2014 23:21:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 741A0201C8 for ; Thu, 8 May 2014 23:21:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8519020035 for ; Thu, 8 May 2014 23:21:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932165AbaEHXVj (ORCPT ); Thu, 8 May 2014 19:21:39 -0400 Received: from mail-ee0-f49.google.com ([74.125.83.49]:60857 "EHLO mail-ee0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932080AbaEHXVi (ORCPT ); Thu, 8 May 2014 19:21:38 -0400 Received: by mail-ee0-f49.google.com with SMTP id e53so2125952eek.8 for ; Thu, 08 May 2014 16:21:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=D7sbdNEbBHVfi0TrO/DS8O42LI74sanL/wVPXy1bPRU=; b=I5tnd7L0EaGR7kLBp9449iHaGjLzGi696jCwZ1wGNo61xVSY/FX4CX5cauIjKpk+qT 1JZDrXpGJv752CoIGt/wtw5jMXTuTfXJ35aeHMsgP4O1/Ojt/f1lLOOHUzaCqKD2yahe JGbSflFwXElgh3rI1EJXmG4vb4j+pTznMA3aNlxFsl4u+c6HE3vlJx6nXFlmuWEEKmo3 Qmr4amh2fIia1ZdAOK0OLi1nMyTSY4fSRD2QoBimWBLDMggWu1B1zAPXTGmu8C3Qz2W3 rErk2MbHuwgWIDs03iMbxCuef/uMfY3AalZvbr/eGrQ3KwAIp2Lm+iHNQNbEk9fNDU/g fWxA== X-Received: by 10.14.127.197 with SMTP id d45mr8654884eei.59.1399591297081; Thu, 08 May 2014 16:21:37 -0700 (PDT) Received: from localhost (13-242.62-81.cust.bluewin.ch. [81.62.242.13]) by mx.google.com with ESMTPSA id x45sm7305356eee.37.2014.05.08.16.21.35 for (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Thu, 08 May 2014 16:21:36 -0700 (PDT) From: Andreas Fenkart To: Tony Lindgren Cc: Chris Ball , Grant Likely , Felipe Balbi , Balaji T K , Andreas Mueller , zonque@gmail.com, galak@codeaurora.org, linux-doc@vger.kernel.org, linux-mmc@vger.kernel.org, linux-omap@vger.kernel.org, Andreas Fenkart Subject: [PATCH v11 7/7] mmc: omap_hsmmc: Pin remux workaround to support SDIO interrupt on AM335x Date: Fri, 9 May 2014 01:20:34 +0200 Message-Id: <1399591234-13089-7-git-send-email-afenkart@gmail.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1399591234-13089-1-git-send-email-afenkart@gmail.com> References: <1399591018-12930-1-git-send-email-afenkart@gmail.com> <1399591234-13089-1-git-send-email-afenkart@gmail.com> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The am335x can't detect pending cirq in PM runtime suspend. This patch reconfigures dat1 as a GPIO before going to suspend. SDIO interrupts are detected with the GPIO, the GPIO will only wake the module from suspend, SDIO irq detection will still happen through the IP block. Idea of remuxing the pins by Tony Lindgren. Code contributions from Tony Lindgren and Balaji T K Signed-off-by: Andreas Fenkart Signed-off-by: Tony Lindgren Conflicts: drivers/mmc/host/omap_hsmmc.c Acked-by: Balaji T K diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt index ce80561..946bc5f 100644 --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt @@ -56,3 +56,56 @@ Examples: &edma 25>; dma-names = "tx", "rx"; }; + +[workaround for missing swakeup on am33xx] + +This SOC is missing the swakeup line, it will not detect SDIO irq +while in suspend. + + ------ + | PRCM | + ------ + ^ | + swakeup | | fclk + | v + ------ ------- ----- + | card | -- CIRQ --> | hsmmc | -- IRQ --> | CPU | + ------ ------- ----- + +In suspend the fclk is off and the module is disfunctional. Even register reads +will fail. A small logic in the host will request fclk restore, when an +external event is detected. Once the clock is restored, the host detects the +event normally. Since am33xx doesn't have this line it never wakes from +suspend. + +The workaround is to reconfigure the dat1 line as a GPIO upon suspend. To make +this work, we need to set the named pinctrl states "default" and "idle". +Prepare idle to remux dat1 as a gpio, and default to remux it back as sdio +dat1. The MMC driver will then toggle between idle and default state during +runtime. + +In summary: +1. select matching 'compatible' section, see example below. +2. specify pinctrl states "default" and "idle", "sleep" is optional. +3. specify the gpio irq used for detecting sdio irq in suspend + +If configuration is incomplete, a warning message is emitted "falling back to +polling". Also check the "sdio irq mode" in /sys/kernel/debug/mmc0/regs. Mind +not every application needs SDIO irq, e.g. MMC cards. + + mmc1: mmc@48060100 { + compatible = "ti,am33xx-hsmmc"; + ... + pinctrl-names = "default", "idle", "sleep" + pinctrl-0 = <&mmc1_pins>; + pinctrl-1 = <&mmc1_idle>; + pinctrl-2 = <&mmc1_sleep>; + ... + interrupts-extended = <&intc 64 &gpio2 28 0>; + }; + + mmc1_idle : pinmux_cirq_pin { + pinctrl-single,pins = < + 0x0f8 0x3f /* GPIO2_28 */ + >; + }; diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 5a321f98..497b2fc 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -1782,15 +1782,25 @@ static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host) * and need to remux SDIO DAT1 to GPIO for wake-up from idle. */ if (host->pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) { - ret = -ENODEV; - devm_free_irq(host->dev, host->wake_irq, host); - goto err; + if (IS_ERR(host->dev->pins->default_state)) { + dev_info(host->dev, "missing default pinctrl state\n"); + ret = -EINVAL; + goto err_free_irq; + } + + if (IS_ERR(host->dev->pins->idle_state)) { + dev_info(host->dev, "missing idle pinctrl state\n"); + ret = -EINVAL; + goto err_free_irq; + } } OMAP_HSMMC_WRITE(host->base, HCTL, OMAP_HSMMC_READ(host->base, HCTL) | IWE); return 0; +err_free_irq: + devm_free_irq(host->dev, host->wake_irq, host); err: dev_warn(host->dev, "no SDIO IRQ support, falling back to polling\n"); host->wake_irq = 0;