Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756285AbZGJMm3 (ORCPT ); Fri, 10 Jul 2009 08:42:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754914AbZGJMjJ (ORCPT ); Fri, 10 Jul 2009 08:39:09 -0400 Received: from smtp.nokia.com ([192.100.122.233]:34988 "EHLO mgw-mx06.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755373AbZGJMjF (ORCPT ); Fri, 10 Jul 2009 08:39:05 -0400 From: Adrian Hunter To: Pierre Ossman Cc: Jarkko Lavinen , Denis Karpov , Adrian Hunter , lkml , linux-omap Mailing List Date: Fri, 10 Jul 2009 15:42:27 +0300 Message-Id: <20090710124227.1262.7056.sendpatchset@ahunter-tower> In-Reply-To: <20090710124004.1262.10422.sendpatchset@ahunter-tower> References: <20090710124004.1262.10422.sendpatchset@ahunter-tower> Subject: [PATCH 20/32] omap_hsmmc: put MMC regulator to sleep X-OriginalArrivalTime: 10 Jul 2009 12:38:53.0768 (UTC) FILETIME=[62615C80:01CA015B] X-Nokia-AV: Clean Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4832 Lines: 155 >From 66c91dd04118c2e2111dade9d5a327c442912046 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Tue, 12 May 2009 20:54:51 +0300 Subject: [PATCH] omap_hsmmc: put MMC regulator to sleep When a card is not in use, the voltage regulator can be put to sleep. This is an alternative to powering the card off, when powering off is not safe because the card might be replaced without the driver being aware of it. That situation happens if: - the card is removable i.e. not eMMC - and there is no card detect - and there is a cover switch but the cover is open Signed-off-by: Adrian Hunter --- drivers/mmc/host/omap_hsmmc.c | 59 +++++++++++++++++++++++++++++++++++++--- 1 files changed, 54 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index c69ab89..eb301c1 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -160,6 +160,7 @@ struct mmc_omap_host { int response_busy; int context_loss; int dpm_state; + int vdd; struct omap_mmc_platform_data *pdata; }; @@ -1031,10 +1032,12 @@ static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) case MMC_POWER_OFF: mmc_slot(host).set_power(host->dev, host->slot_id, 0, 0); + host->vdd = 0; break; case MMC_POWER_UP: mmc_slot(host).set_power(host->dev, host->slot_id, 1, ios->vdd); + host->vdd = ios->vdd; break; case MMC_POWER_ON: do_send_init_stream = 1; @@ -1172,19 +1175,20 @@ static void omap_hsmmc_init(struct mmc_omap_host *host) /* * Dynamic power saving handling, FSM: - * ENABLED -> DISABLED -> OFF + * ENABLED -> DISABLED -> OFF / REGSLEEP * ^___________| | * |______________________| * * ENABLED: mmc host is fully functional * DISABLED: fclk is off * OFF: fclk is off,voltage regulator is off + * REGSLEEP: fclk is off,voltage regulator is asleep * * Transition handlers return the timeout for the next state transition * or negative error. */ -enum {ENABLED = 0, DISABLED, OFF}; +enum {ENABLED = 0, DISABLED, REGSLEEP, OFF}; /* Handler for [ENABLED -> DISABLED] transition */ static int omap_mmc_enabled_to_disabled(struct mmc_omap_host *host) @@ -1221,8 +1225,12 @@ static int omap_mmc_disabled_to_off(struct mmc_omap_host *host) mmc_slot(host).get_cover_state(host->dev, host->slot_id))) { mmc_power_save_host(host->mmc); new_state = OFF; - } else - new_state = DISABLED; + } else { + if (mmc_slot(host).set_sleep) + mmc_slot(host).set_sleep(host->dev, host->slot_id, + 1, 0, 0); + new_state = REGSLEEP; + } OMAP_HSMMC_WRITE(host->base, ISE, 0); OMAP_HSMMC_WRITE(host->base, IE, 0); @@ -1279,6 +1287,44 @@ static int omap_mmc_off_to_enabled(struct mmc_omap_host *host) return 0; } +/* Handler for [REGSLEEP -> ENABLED] transition */ +static int omap_mmc_regsleep_to_enabled(struct mmc_omap_host *host) +{ + unsigned long timeout; + + dev_dbg(mmc_dev(host->mmc), "REGSLEEP -> ENABLED\n"); + + clk_enable(host->fclk); + clk_enable(host->iclk); + + if (clk_enable(host->dbclk)) + dev_dbg(mmc_dev(host->mmc), + "Enabling debounce clk failed\n"); + + omap_mmc_restore_ctx(host); + + /* + * We turned off interrupts and bus power. Interrupts + * are turned on by 'mmc_omap_start_command()' so we + * just need to turn on the bus power here. + */ + OMAP_HSMMC_WRITE(host->base, HCTL, + OMAP_HSMMC_READ(host->base, HCTL) | SDBP); + + timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS); + while ((OMAP_HSMMC_READ(host->base, HCTL) & SDBP) != SDBP && + time_before(jiffies, timeout)) + ; + + if (mmc_slot(host).set_sleep) + mmc_slot(host).set_sleep(host->dev, host->slot_id, + 0, host->vdd, 0); + + host->dpm_state = ENABLED; + + return 0; +} + /* * Bring MMC host to ENABLED from any other PM state. */ @@ -1289,6 +1335,8 @@ static int omap_mmc_enable(struct mmc_host *mmc) switch (host->dpm_state) { case DISABLED: return omap_mmc_disabled_to_enabled(host); + case REGSLEEP: + return omap_mmc_regsleep_to_enabled(host); case OFF: return omap_mmc_off_to_enabled(host); default: @@ -1386,7 +1434,8 @@ static int mmc_regs_show(struct seq_file *s, void *data) host->dpm_state, mmc->nesting_cnt, host->context_loss, context_loss); - if (host->suspended || host->dpm_state == OFF) { + if (host->suspended || host->dpm_state == OFF || + host->dpm_state == REGSLEEP) { seq_printf(s, "host suspended, can't read registers\n"); return 0; } -- 1.5.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/