From patchwork Wed Nov 18 23:20:47 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steve deRosier X-Patchwork-Id: 7653441 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: X-Original-To: patchwork-linux-wireless@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0FDC0BF90C for ; Wed, 18 Nov 2015 23:22:43 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0EA382045E for ; Wed, 18 Nov 2015 23:22:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 27864205EE for ; Wed, 18 Nov 2015 23:22:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757382AbbKRXWj (ORCPT ); Wed, 18 Nov 2015 18:22:39 -0500 Received: from mail-qg0-f54.google.com ([209.85.192.54]:33279 "EHLO mail-qg0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757222AbbKRXWi (ORCPT ); Wed, 18 Nov 2015 18:22:38 -0500 Received: by qgea14 with SMTP id a14so40139770qge.0 for ; Wed, 18 Nov 2015 15:22:37 -0800 (PST) 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=UWlruAaUFYeK+dAMaH6uJb6F0lzNVVKb0rVMRqIfjbc=; b=v4P/TeXu/ob1CGbkofR1Hv+WGTXldJ+HuzFgWtdJsh2h0o2IXva/XHfliqWyLnJYIk U4v7/dk/f1tp2QgwtEfqECHxzsbioe3lmtfIeVgl1aA/i70rBspm9DTaX7CeFj5OXodZ oCtbB6/ygXf4oyBYptW6I65lTcv2vidT+1H/N5rCZnLIRHxwNw+3ZEfXU4c1FhQnlb25 hGVutY51gWTpsx+fnlemXVl3pA6LEBF88ZBq+pFrhf4scmvSwhyPkpl3bBWgO/lMM83G dnHGA0Vi1vD7j0QNF171KASjSvl4kSzYT45S/TOu5dPk+VfdmtpCPU/vAvQwLWC0tscB rvKg== X-Received: by 10.141.4.4 with SMTP id g4mr4550416qhd.45.1447888957195; Wed, 18 Nov 2015 15:22:37 -0800 (PST) Received: from elmer.corp.lairdtech.com (c-50-184-185-234.hsd1.ca.comcast.net. [50.184.185.234]) by smtp.gmail.com with ESMTPSA id v202sm739351qka.38.2015.11.18.15.22.36 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 18 Nov 2015 15:22:36 -0800 (PST) From: Steve deRosier X-Google-Original-From: Steve deRosier To: Kalle Valo Cc: ath6kl@lists.infradead.org, linux-wireless@vger.kernel.org, Steve deRosier Subject: [PATCH v2 1/2] ath6kl_sdio: Add reset gpio module parameter for CHIP_PWD_L pin Date: Wed, 18 Nov 2015 15:20:47 -0800 Message-Id: <1447888848-19530-2-git-send-email-steve.derosier@lairdtech.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1447888848-19530-1-git-send-email-steve.derosier@lairdtech.com> References: <1447888848-19530-1-git-send-email-steve.derosier@lairdtech.com> Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Spam-Status: No, score=-7.3 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 Many ath6k chips have a reset pin, usually labeled CHIP_PWD_L. This pin can be pulled low by the host processor to hold the wifi chip in reset. By holding the chip in reset, the lowest power consumption available can be achieved. This adds a module parameter so the ath6kl_sdio driver can control the CHIP_PWD_L pin if the implementer so desires. This code is only available if GPIOLIB is configured. Signed-off-by: Steve deRosier --- drivers/net/wireless/ath/ath6kl/sdio.c | 73 +++++++++++++++++++++++++++++++++- 1 file changed, 72 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath6kl/sdio.c b/drivers/net/wireless/ath/ath6kl/sdio.c index eab0ab9..c0755eb 100644 --- a/drivers/net/wireless/ath/ath6kl/sdio.c +++ b/drivers/net/wireless/ath/ath6kl/sdio.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "hif.h" #include "hif-ops.h" #include "target.h" @@ -67,8 +68,15 @@ struct ath6kl_sdio { /* protects access to wr_asyncq */ spinlock_t wr_async_lock; + }; +static unsigned int reset_pwd_gpio = ARCH_NR_GPIOS; +#ifdef CONFIG_GPIOLIB +module_param(reset_pwd_gpio, uint, 0644); +MODULE_PARM_DESC(reset_pwd_gpio, "WIFI CHIP_PWD reset pin GPIO"); +#endif + #define CMD53_ARG_READ 0 #define CMD53_ARG_WRITE 1 #define CMD53_ARG_BLOCK_BASIS 1 @@ -1414,20 +1422,83 @@ static struct sdio_driver ath6kl_sdio_driver = { .drv.pm = ATH6KL_SDIO_PM_OPS, }; +/* Delay to avoid the mmc driver calling the probe on the prior notice of + * the chip, which we just killed. If this is missing, it results in a + * spurious warning: + * "ath6kl_sdio: probe of mmc0:0001:1 failed with error -110" + * + * Time chosen experimentally, with padding + */ +#define ATH6KL_MMC_PROBE_DELAY 150 + +static int ath6kl_sdio_init_gpio(void) +{ + int ret = 0; + + if (gpio_is_valid(reset_pwd_gpio)) { + /* Request the reset GPIO, and assert it to make sure we get a + * clean boot in-case we had a floating input or other issue. + */ + ret = gpio_request_one(reset_pwd_gpio, + GPIOF_OUT_INIT_LOW | + GPIOF_EXPORT_DIR_FIXED, + "WIFI_RESET"); + if (ret) { + ath6kl_err("Unable to get WIFI power gpio: %d\n", ret); + return ret; + } + + ath6kl_dbg(ATH6KL_DBG_SUSPEND, "Setup wifi gpio #%d\n", + reset_pwd_gpio); + usleep_range(20, 50); /* Pin must be asserted at least 5 usec */ + gpio_set_value(reset_pwd_gpio, 1); /* De-assert the pin */ + + msleep(ATH6KL_MMC_PROBE_DELAY); + } + + return 0; +} + +static void ath6kl_sdio_release_gpio(void) +{ + if (gpio_is_valid(reset_pwd_gpio)) { + /* Be sure we leave the chip in reset when we unload and also + * release the GPIO + */ + gpio_set_value(reset_pwd_gpio, 0); + gpio_free(reset_pwd_gpio); + } +} + static int __init ath6kl_sdio_init(void) { int ret; - ret = sdio_register_driver(&ath6kl_sdio_driver); + ret = ath6kl_sdio_init_gpio(); if (ret) + goto err_gpio; + + ret = sdio_register_driver(&ath6kl_sdio_driver); + if (ret) { ath6kl_err("sdio driver registration failed: %d\n", ret); + goto err_register; + } return ret; + +err_register: + ath6kl_sdio_release_gpio(); + +err_gpio: + return ret; } static void __exit ath6kl_sdio_exit(void) { sdio_unregister_driver(&ath6kl_sdio_driver); + + if (gpio_is_valid(reset_pwd_gpio)) + ath6kl_sdio_release_gpio(); } module_init(ath6kl_sdio_init);