From patchwork Wed Jan 23 09:45:44 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Philip, Avinash" X-Patchwork-Id: 214863 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 003582C0082 for ; Wed, 23 Jan 2013 20:46:17 +1100 (EST) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TxwtX-00088e-P7; Wed, 23 Jan 2013 09:45:23 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TxwtV-00087G-HP; Wed, 23 Jan 2013 09:45:22 +0000 Received: from dbdp20.itg.ti.com ([172.24.170.38]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id r0N9jEgQ009080; Wed, 23 Jan 2013 03:45:15 -0600 Received: from DBDE71.ent.ti.com (localhost [127.0.0.1]) by dbdp20.itg.ti.com (8.13.8/8.13.8) with ESMTP id r0N9jBnH003973; Wed, 23 Jan 2013 15:15:12 +0530 (IST) Received: from dbdp32.itg.ti.com (172.24.170.251) by DBDE71.ent.ti.com (172.24.170.149) with Microsoft SMTP Server id 14.1.323.3; Wed, 23 Jan 2013 15:15:11 +0530 Received: from ucmsshproxy.india.ext.ti.com (dbdp20.itg.ti.com [172.24.170.38]) by dbdp32.itg.ti.com (8.13.8/8.13.8) with SMTP id r0N9j8u9003329; Wed, 23 Jan 2013 15:15:08 +0530 Received: from symphony.india.ext.ti.com (unknown [192.168.247.13]) by ucmsshproxy.india.ext.ti.com (Postfix) with ESMTP id 52C0E158003; Wed, 23 Jan 2013 15:15:06 +0530 (IST) Received: from ubuntu-psp-linux.india.ext.ti.com (ubuntu-psp-linux [192.168.247.46]) by symphony.india.ext.ti.com (8.11.7p1+Sun/8.11.7) with ESMTP id r0N9ixR28685; Wed, 23 Jan 2013 15:14:59 +0530 (IST) From: Philip Avinash To: , , , Subject: [PATCH 2/4] mtd: devices: elm: Low power transition support Date: Wed, 23 Jan 2013 15:15:44 +0530 Message-ID: <1358934346-16822-3-git-send-email-avinashphilip@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1358933176-12409-1-git-send-email-avinashphilip@ti.com> References: <1358933176-12409-1-git-send-email-avinashphilip@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130123_044521_654987_B457C4A1 X-CRM114-Status: GOOD ( 14.02 ) X-Spam-Score: -4.6 (----) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-4.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [192.94.94.40 listed in list.dnswl.org] 3.0 KHOP_BIG_TO_CC Sent to 10+ recipients instaed of Bcc or a list -0.0 SPF_PASS SPF: sender matches SPF record -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: afzal@ti.com, nsekhar@ti.com, linux-kernel@vger.kernel.org, gururaja.hebbar@ti.com, linux-mtd@lists.infradead.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-mtd-bounces@lists.infradead.org Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org In low power modes of AM335X platforms, peripherals power is cut off. This patch supports low power sleep transition support for ELM driver. Signed-off-by: Philip Avinash --- drivers/mtd/devices/elm.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/mtd/devices/elm.c b/drivers/mtd/devices/elm.c index f78f43f..4793cb0 100644 --- a/drivers/mtd/devices/elm.c +++ b/drivers/mtd/devices/elm.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -62,6 +63,7 @@ struct elm_info { struct completion elm_completion; struct list_head list; enum bch_ecc bch_type; + bool idle; }; static LIST_HEAD(elm_devices); @@ -86,9 +88,11 @@ void elm_config(struct device *dev, enum bch_ecc bch_type) u32 reg_val; struct elm_info *info = dev_get_drvdata(dev); + info->idle = true; reg_val = (bch_type & ECC_BCH_LEVEL_MASK) | (ELM_ECC_SIZE << 16); elm_write_reg(info, ELM_LOCATION_CONFIG, reg_val); info->bch_type = bch_type; + info->idle = false; } EXPORT_SYMBOL(elm_config); @@ -280,6 +284,7 @@ void elm_decode_bch_error_page(struct device *dev, u8 *ecc_calc, struct elm_info *info = dev_get_drvdata(dev); u32 reg_val; + info->idle = true; /* Enable page mode interrupt */ reg_val = elm_read_reg(info, ELM_IRQSTATUS); elm_write_reg(info, ELM_IRQSTATUS, reg_val & INTR_STATUS_PAGE_VALID); @@ -298,6 +303,7 @@ void elm_decode_bch_error_page(struct device *dev, u8 *ecc_calc, reg_val = elm_read_reg(info, ELM_IRQENABLE); elm_write_reg(info, ELM_IRQENABLE, reg_val & ~INTR_EN_PAGE_MASK); elm_error_correction(info, err_vec); + info->idle = false; } EXPORT_SYMBOL(elm_decode_bch_error_page); @@ -368,6 +374,7 @@ static int elm_probe(struct platform_device *pdev) INIT_LIST_HEAD(&info->list); list_add(&info->list, &elm_devices); platform_set_drvdata(pdev, info); + info->idle = false; return ret; } @@ -379,6 +386,38 @@ static int elm_remove(struct platform_device *pdev) return 0; } +static int elm_suspend(struct device *dev) +{ + struct elm_info *info = dev_get_drvdata(dev); + wait_queue_head_t wq; + DECLARE_WAITQUEUE(wait, current); + + init_waitqueue_head(&wq); + while (1) { + /* Make sure that ELM not running */ + if (info->idle) { + add_wait_queue(&wq, &wait); + schedule(); + remove_wait_queue(&wq, &wait); + } else { + break; + } + } + pm_runtime_put_sync(dev); + return 0; +} + +static int elm_resume(struct device *dev) +{ + struct elm_info *info = dev_get_drvdata(dev); + + pm_runtime_get_sync(dev); + elm_config(dev, info->bch_type); + return 0; +} + +static SIMPLE_DEV_PM_OPS(elm_pm_ops, elm_suspend, elm_resume); + #ifdef CONFIG_OF static const struct of_device_id elm_of_match[] = { { .compatible = "ti,am33xx-elm" }, @@ -392,6 +431,7 @@ static struct platform_driver elm_driver = { .name = "elm", .owner = THIS_MODULE, .of_match_table = of_match_ptr(elm_of_match), + .pm = &elm_pm_ops, }, .probe = elm_probe, .remove = elm_remove,