From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulf Hansson Subject: Re: [PATCH V2] MMC-4.5 Power OFF Notify rework Date: Mon, 30 Apr 2012 10:39:29 +0200 Message-ID: <4F9E4FC1.3010505@stericsson.com> References: <1335766496-15966-1-git-send-email-girish.shivananjappa@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from eu1sys200aog108.obsmtp.com ([207.126.144.125]:51073 "EHLO eu1sys200aog108.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754871Ab2D3Ijl (ORCPT ); Mon, 30 Apr 2012 04:39:41 -0400 In-Reply-To: <1335766496-15966-1-git-send-email-girish.shivananjappa@linaro.org> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Girish K S Cc: "linux-mmc@vger.kernel.org" , "patches@linaro.org" , "saugata.das@linaro.org" On 04/30/2012 08:14 AM, Girish K S wrote: > This is a rework of the existing POWER OFF NOTIFY patch. The current problem > with the patch comes from the ambiguity on the usage of POWER OFF NOTIFY > together with SLEEP and misunderstanding on the usage of MMC_POWER_OFF > power_mode from mmc_set_ios in different host controller drivers. > > This new patch works around this problem by adding a new host CAP, > MMC_CAP2_POWER_OFF_VCCQ_DURING_SUSPEND, which when set sends a > POWER OFF NOTIFY from mmc_suspend instead of SLEEP. It is expected that host > controller drivers will set this CAP, if they switch off both Vcc and Vccq > from MMC_POWER_OFF condition within mmc_set_ios. However, note that there > is no harm in sending MMC_POWER_NOTIFY even if Vccq is not switched off. > > This patch also sends POWER OFF NOTIFY from power management routines (e.g. > mmc_power_save_host, mmc_pm_notify/PM_SUSPEND_PREPARE, mmc_stop_host), which > does reinitialization of the eMMC on the return path of the power management > routines (e.g. mmc_power_restore_host, mmc_pm_notify/PM_POST_RESTORE, > mmc_start_host). > > This patch sets POWER_OFF_NOTIFICATION to POWER_OFF_SHORT if it is sent from > the suspend sequence. If it is sent from shutdown sequence then it is set to > POWER_OFF_LONG. > > Previuos implementation of PowerOff Notify as a core function is replaced as > a device's bus operation. > > Signed-off-by: Saugata Das > Signed-off-by: Girish K S > --- > drivers/mmc/core/core.c | 95 +++++++++++++++------------------------------ > drivers/mmc/core/core.h | 1 + > drivers/mmc/core/mmc.c | 76 +++++++++++++++++++++++++++++++------ > include/linux/mmc/host.h | 1 + > 4 files changed, 98 insertions(+), 75 deletions(-) > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index ba821fe..7f5461e 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -1100,48 +1100,6 @@ void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type) > mmc_host_clk_release(host); > } > > -static void mmc_poweroff_notify(struct mmc_host *host) > -{ > - struct mmc_card *card; > - unsigned int timeout; > - unsigned int notify_type = EXT_CSD_NO_POWER_NOTIFICATION; > - int err = 0; > - > - card = host->card; > - mmc_claim_host(host); > - > - /* > - * Send power notify command only if card > - * is mmc and notify state is powered ON > - */ > - if (card&& mmc_card_mmc(card)&& > - (card->poweroff_notify_state == MMC_POWERED_ON)) { > - > - if (host->power_notify_type == MMC_HOST_PW_NOTIFY_SHORT) { > - notify_type = EXT_CSD_POWER_OFF_SHORT; > - timeout = card->ext_csd.generic_cmd6_time; > - card->poweroff_notify_state = MMC_POWEROFF_SHORT; > - } else { > - notify_type = EXT_CSD_POWER_OFF_LONG; > - timeout = card->ext_csd.power_off_longtime; > - card->poweroff_notify_state = MMC_POWEROFF_LONG; > - } > - > - err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > - EXT_CSD_POWER_OFF_NOTIFICATION, > - notify_type, timeout); > - > - if (err&& err != -EBADMSG) > - pr_err("Device failed to respond within %d poweroff " > - "time. Forcefully powering down the device\n", > - timeout); > - > - /* Set the card state to no notification after the poweroff */ > - card->poweroff_notify_state = MMC_NO_POWER_NOTIFICATION; > - } > - mmc_release_host(host); > -} > - > /* > * Apply power to the MMC stack. This is a two-stage process. > * First, we enable power to the card without the clock running. > @@ -1198,30 +1156,12 @@ static void mmc_power_up(struct mmc_host *host) > > void mmc_power_off(struct mmc_host *host) > { > - int err = 0; > mmc_host_clk_hold(host); > > host->ios.clock = 0; > host->ios.vdd = 0; > > /* > - * For eMMC 4.5 device send AWAKE command before > - * POWER_OFF_NOTIFY command, because in sleep state > - * eMMC 4.5 devices respond to only RESET and AWAKE cmd > - */ > - if (host->card&& mmc_card_is_sleep(host->card)&& > - host->bus_ops->resume) { > - err = host->bus_ops->resume(host); > - > - if (!err) > - mmc_poweroff_notify(host); > - else > - pr_warning("%s: error %d during resume " > - "(continue with poweroff sequence)\n", > - mmc_hostname(host), err); > - } > - > - /* > * Reset ocr mask to be the highest possible voltage supported for > * this mmc host. This value will be used at next power up. > */ > @@ -2084,6 +2024,14 @@ void mmc_stop_host(struct mmc_host *host) > > mmc_bus_get(host); > if (host->bus_ops&& !host->bus_dead) { > + > + if (host->bus_ops->poweroff_notify) { > + int err = host->bus_ops->poweroff_notify(host); > + if (err) > + pr_info("%s: error [%x] in poweroff notify\n", > + mmc_hostname(host), err); > + } > + > /* Calling bus_ops->remove() with a claimed host can deadlock */ > if (host->bus_ops->remove) > host->bus_ops->remove(host); > @@ -2093,6 +2041,7 @@ void mmc_stop_host(struct mmc_host *host) > mmc_power_off(host); > mmc_release_host(host); > mmc_bus_put(host); > + > return; > } > mmc_bus_put(host); > @@ -2119,6 +2068,13 @@ int mmc_power_save_host(struct mmc_host *host) > > if (host->bus_ops->power_save) > ret = host->bus_ops->power_save(host); > + host->power_notify_type = MMC_HOST_PW_NOTIFY_SHORT; > + if (host->bus_ops->poweroff_notify) { > + int err = host->bus_ops->poweroff_notify(host); > + if (err) > + pr_info("%s: error [%x] in poweroff notify\n", > + mmc_hostname(host), err); > + } > > mmc_bus_put(host); > > @@ -2142,7 +2098,7 @@ int mmc_power_restore_host(struct mmc_host *host) > mmc_bus_put(host); > return -EINVAL; > } > - > + host->power_notify_type = MMC_HOST_PW_NOTIFY_LONG; > mmc_power_up(host); > ret = host->bus_ops->power_restore(host); > > @@ -2161,8 +2117,11 @@ int mmc_card_awake(struct mmc_host *host) > > mmc_bus_get(host); > > - if (host->bus_ops&& !host->bus_dead&& host->bus_ops->awake) > + if (host->bus_ops&& !host->bus_dead&& host->bus_ops->awake) { > err = host->bus_ops->awake(host); > + if (!err) > + mmc_card_clr_sleep(host->card); > + } > > mmc_bus_put(host); > > @@ -2179,8 +2138,11 @@ int mmc_card_sleep(struct mmc_host *host) > > mmc_bus_get(host); > > - if (host->bus_ops&& !host->bus_dead&& host->bus_ops->sleep) > + if (host->bus_ops&& !host->bus_dead&& host->bus_ops->sleep) { > err = host->bus_ops->sleep(host); > + if (!err) > + mmc_card_set_sleep(host->card); > + } > > mmc_bus_put(host); > > @@ -2379,6 +2341,12 @@ int mmc_pm_notify(struct notifier_block *notify_block, > > if (!host->bus_ops || host->bus_ops->suspend) > break; > + if (host->bus_ops->poweroff_notify) { > + int err = host->bus_ops->poweroff_notify(host); > + if (err) > + pr_info("%s: error [%x] in poweroff notify\n", > + mmc_hostname(host), err); > + } > > /* Calling bus_ops->remove() with a claimed host can deadlock */ > if (host->bus_ops->remove) > @@ -2388,6 +2356,7 @@ int mmc_pm_notify(struct notifier_block *notify_block, > mmc_detach_bus(host); > mmc_power_off(host); > mmc_release_host(host); > + > host->pm_flags = 0; > break; > > diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h > index 3bdafbc..351cbbe 100644 > --- a/drivers/mmc/core/core.h > +++ b/drivers/mmc/core/core.h > @@ -25,6 +25,7 @@ struct mmc_bus_ops { > int (*power_save)(struct mmc_host *); > int (*power_restore)(struct mmc_host *); > int (*alive)(struct mmc_host *); > + int (*poweroff_notify)(struct mmc_host *); > }; > > void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops); > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index 54df5ad..11ab536 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -1282,6 +1282,50 @@ err: > return err; > } > > +static int mmc_poweroff_notify(struct mmc_host *host) > +{ > + struct mmc_card *card; > + unsigned int timeout; > + unsigned int notify_type = EXT_CSD_NO_POWER_NOTIFICATION; > + int err = -EOPNOTSUPP; > + > + card = host->card; > + mmc_claim_host(host); > + > + /* > + * Send power notify command only if card > + * is mmc and notify state is powered ON > + */ > + if (card&& mmc_card_mmc(card)&& > + (card->poweroff_notify_state == MMC_POWERED_ON)) { > + > + if (host->power_notify_type == MMC_HOST_PW_NOTIFY_SHORT) { > + notify_type = EXT_CSD_POWER_OFF_SHORT; > + timeout = card->ext_csd.generic_cmd6_time; > + card->poweroff_notify_state = MMC_POWEROFF_SHORT; > + } else { > + notify_type = EXT_CSD_POWER_OFF_LONG; > + timeout = card->ext_csd.power_off_longtime; > + card->poweroff_notify_state = MMC_POWEROFF_LONG; > + } > + > + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > + EXT_CSD_POWER_OFF_NOTIFICATION, > + notify_type, timeout); > + > + if (err&& err != -EBADMSG) > + pr_err("%s: Device failed to respond within %d " > + "poweroff time. Forcefully powering down " > + "the device\n", mmc_hostname(host), timeout); > + > + /* Set the card state to no notification after the poweroff */ > + card->poweroff_notify_state = MMC_NO_POWER_NOTIFICATION; > + } > + mmc_release_host(host); > + > + return err; > +} > + > /* > * Host is being removed. Free up the current card. > */ > @@ -1341,15 +1385,21 @@ static int mmc_suspend(struct mmc_host *host) > BUG_ON(!host); > BUG_ON(!host->card); > > - mmc_claim_host(host); > - if (mmc_card_can_sleep(host)) { > - err = mmc_card_sleep(host); > - if (!err) > - mmc_card_set_sleep(host->card); > - } else if (!mmc_host_is_spi(host)) > - mmc_deselect_cards(host); > - host->card->state&= ~(MMC_STATE_HIGHSPEED | MMC_STATE_HIGHSPEED_200); > - mmc_release_host(host); > + if ((host->card)&& mmc_card_mmc(host->card)&& > + (host->caps2& MMC_CAP2_POWER_OFF_VCCQ_DURING_SUSPEND)) { > + err = mmc_poweroff_notify(host); This still wont work. What if the card supports sleep but not poweroff_notify. At the same time the host is able to cut VCCQ. Then the poweroff_notify will be issued and fail. Instead sleep should be issued. Again, a "mmc_card_can_poweroff_notify" would be useful here. > + } else { > + mmc_claim_host(host); > + if (mmc_card_can_sleep(host)) > + err = mmc_card_sleep(host); > + else if (!mmc_host_is_spi(host)) > + mmc_deselect_cards(host); > + mmc_release_host(host); > + } > + > + if (!err) > + host->card->state&= > + ~(MMC_STATE_HIGHSPEED | MMC_STATE_HIGHSPEED_200); > > return err; > } > @@ -1368,11 +1418,11 @@ static int mmc_resume(struct mmc_host *host) > BUG_ON(!host->card); > > mmc_claim_host(host); > - if (mmc_card_is_sleep(host->card)) { > + if (mmc_card_is_sleep(host->card)) > err = mmc_card_awake(host); > - mmc_card_clr_sleep(host->card); > - } else > + else > err = mmc_init_card(host, host->ocr, host->card); > + > mmc_release_host(host); > > return err; > @@ -1430,6 +1480,7 @@ static const struct mmc_bus_ops mmc_ops = { > .resume = NULL, > .power_restore = mmc_power_restore, > .alive = mmc_alive, > + .poweroff_notify = mmc_poweroff_notify, > }; > > static const struct mmc_bus_ops mmc_ops_unsafe = { > @@ -1441,6 +1492,7 @@ static const struct mmc_bus_ops mmc_ops_unsafe = { > .resume = mmc_resume, > .power_restore = mmc_power_restore, > .alive = mmc_alive, > + .poweroff_notify = mmc_poweroff_notify, > }; > > static void mmc_attach_bus_ops(struct mmc_host *host) > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index 0707d22..986e22b 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -238,6 +238,7 @@ struct mmc_host { > #define MMC_CAP2_BROKEN_VOLTAGE (1<< 7) /* Use the broken voltage */ > #define MMC_CAP2_DETECT_ON_ERR (1<< 8) /* On I/O err check card removal */ > #define MMC_CAP2_HC_ERASE_SZ (1<< 9) /* High-capacity erase size */ > +#define MMC_CAP2_POWER_OFF_VCCQ_DURING_SUSPEND (1<< 10) > > mmc_pm_flag_t pm_caps; /* supported pm features */ > unsigned int power_notify_type; Kind regards Ulf Hansson