Hi Girish, Saugata, There is an issue with this patch during resume. Please find comments inline below: > -----Original Message----- > From: Girish K S [mailto:girish.shivananjappa@xxxxxxxxxx] > Sent: Tuesday, May 22, 2012 5:15 PM > To: linux-mmc@xxxxxxxxxxxxxxx > Cc: cjb@xxxxxxxxxx; patches@xxxxxxxxxx; ulf.hansson@xxxxxxxxxxxxxx; > saugata.das@xxxxxxxxxx; subhashj@xxxxxxxxxxxxxx; Girish K S > Subject: [PATCH v5] MMC-4.5 Power OFF Notify Rework > > From: Saugata Das <saugata.das@xxxxxxxxxx> > > 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. > > Earlier implementation of PowerOff Notify as a core function is replaced as a > device's bus operation. > > Signed-off-by: Saugata Das <saugata.das@xxxxxxxxxx> > Signed-off-by: Girish K S <girish.shivananjappa@xxxxxxxxxx> > > changes in v5: > modified the the handling of return value in mmc_poweroff_notify. > changes in v4: > As suggested in review, > - Moved mmc_can_poweroff_notify to core.c > - Moved mmc_claim_host, mmc_release_host outside > mmc_poweroff_notify > - Added check for wrong initialization for poweroff_notify_type > - mmc_poweroff_notify is modified to take as 2nd parameter changes > in v3: > This version addresses the review comments given by Subhash and Ulf > changes in v2: > This version addresses the changes suggested by Ulf > --- > drivers/mmc/core/core.c | 108 ++++++++++++++++++-------------------------- > drivers/mmc/core/core.h | 1 + > drivers/mmc/core/mmc.c | 56 ++++++++++++++++++++--- > drivers/mmc/host/dw_mmc.c | 5 -- > drivers/mmc/host/sdhci.c | 9 ---- > include/linux/mmc/card.h | 5 +- > include/linux/mmc/core.h | 1 + > include/linux/mmc/host.h | 5 +-- > include/linux/mmc/mmc.h | 7 +++ > 9 files changed, 104 insertions(+), 93 deletions(-) > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index > 0b6141d..fe616b9 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -1101,48 +1101,6 @@ 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. > @@ -1202,8 +1160,6 @@ static void mmc_power_up(struct mmc_host *host) > > void mmc_power_off(struct mmc_host *host) { > - int err = 0; > - > if (host->ios.power_mode == MMC_POWER_OFF) > return; > > @@ -1212,22 +1168,6 @@ void mmc_power_off(struct mmc_host *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 @@ > -1726,6 +1666,15 @@ int mmc_can_secure_erase_trim(struct mmc_card > *card) } EXPORT_SYMBOL(mmc_can_secure_erase_trim); > > +int mmc_can_poweroff_notify(const struct mmc_card *card) { > + return card && > + mmc_card_mmc(card) && > + card->host->bus_ops->poweroff_notify && > + (card->poweroff_notify_state == MMC_POWERED_ON); } > +EXPORT_SYMBOL(mmc_can_poweroff_notify); > + > int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from, > unsigned int nr) > { > @@ -2096,6 +2045,15 @@ void mmc_stop_host(struct mmc_host *host) > > mmc_bus_get(host); > if (host->bus_ops && !host->bus_dead) { > + mmc_claim_host(host); > + if (mmc_can_poweroff_notify(host->card)) { > + int err = host->bus_ops->poweroff_notify(host, > + > MMC_PW_OFF_NOTIFY_LONG); > + if (err) > + pr_info("%s: error [%d] in poweroff notify\n", > + mmc_hostname(host), err); > + } > + mmc_release_host(host); > /* Calling bus_ops->remove() with a claimed host can deadlock > */ > if (host->bus_ops->remove) > host->bus_ops->remove(host); > @@ -2131,6 +2089,15 @@ int mmc_power_save_host(struct mmc_host *host) > > if (host->bus_ops->power_save) > ret = host->bus_ops->power_save(host); > + mmc_claim_host(host); > + if (mmc_can_poweroff_notify(host->card)) { > + int err = host->bus_ops->poweroff_notify(host, > + MMC_PW_OFF_NOTIFY_SHORT); > + if (err) > + pr_info("%s: error [%d] in poweroff notify\n", > + mmc_hostname(host), err); > + } > + mmc_release_host(host); > > mmc_bus_put(host); > > @@ -2173,8 +2140,11 @@ 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); > > @@ -2191,8 +2161,11 @@ 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); > > @@ -2385,12 +2358,20 @@ int mmc_pm_notify(struct notifier_block > *notify_block, > > spin_lock_irqsave(&host->lock, flags); > host->rescan_disable = 1; > - host->power_notify_type = MMC_HOST_PW_NOTIFY_SHORT; > spin_unlock_irqrestore(&host->lock, flags); > cancel_delayed_work_sync(&host->detect); > > if (!host->bus_ops || host->bus_ops->suspend) > break; > + mmc_claim_host(host); > + if (mmc_can_poweroff_notify(host->card)) { > + int err = host->bus_ops->poweroff_notify(host, > + > MMC_PW_OFF_NOTIFY_SHORT); > + if (err) > + pr_info("%s: error [%d] in poweroff notify\n", > + mmc_hostname(host), err); > + } > + mmc_release_host(host); > > /* Calling bus_ops->remove() with a claimed host can deadlock > */ > if (host->bus_ops->remove) > @@ -2409,7 +2390,6 @@ int mmc_pm_notify(struct notifier_block > *notify_block, > > spin_lock_irqsave(&host->lock, flags); > host->rescan_disable = 0; > - host->power_notify_type = MMC_HOST_PW_NOTIFY_LONG; > spin_unlock_irqrestore(&host->lock, flags); > mmc_detect_change(host, 0); > > diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h index > 3bdafbc..15b918d 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 *, int notify); > }; > > 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 > 2f0e11c..042dbdc 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -1259,6 +1259,40 @@ err: > return err; > } > > +static int mmc_poweroff_notify(struct mmc_host *host, int notify) { > + struct mmc_card *card; > + unsigned int timeout; > + unsigned int notify_type = EXT_CSD_NO_POWER_NOTIFICATION; > + int err; > + > + card = host->card; > + > + if (notify == MMC_PW_OFF_NOTIFY_SHORT) { > + notify_type = EXT_CSD_POWER_OFF_SHORT; > + timeout = card->ext_csd.generic_cmd6_time; > + } else if (notify == MMC_PW_OFF_NOTIFY_LONG) { > + notify_type = EXT_CSD_POWER_OFF_LONG; > + timeout = card->ext_csd.power_off_longtime; > + } else { > + pr_info("%s: mmc_poweroff_notify called " > + "with notify type %d\n", mmc_hostname(host), notify); > + return -EINVAL; > + } > + > + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > + EXT_CSD_POWER_OFF_NOTIFICATION, > + notify_type, timeout); > + > + if (err) > + pr_err("%s: Device failed to respond within %d " > + "poweroff timeout.\n", mmc_hostname(host), timeout); > + else > + card->poweroff_notify_state = > + MMC_NO_POWER_NOTIFICATION; > + > + return err; > +} > /* > * Host is being removed. Free up the current card. > */ > @@ -1319,13 +1353,18 @@ static int mmc_suspend(struct mmc_host *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); > + if (mmc_can_poweroff_notify(host->card) && > + (host->caps2 & > MMC_CAP2_POWER_OFF_VCCQ_DURING_SUSPEND)) { > + err = mmc_poweroff_notify(host, > MMC_PW_OFF_NOTIFY_SHORT); > + } else { > + if (mmc_card_can_sleep(host)) > + err = mmc_card_sleep(host); > + else if (!mmc_host_is_spi(host)) > + mmc_deselect_cards(host); > + } > + if (!err) > + host->card->state &= > + ~(MMC_STATE_HIGHSPEED | > MMC_STATE_HIGHSPEED_200); > mmc_release_host(host); > > return err; > @@ -1347,7 +1386,6 @@ static int mmc_resume(struct mmc_host *host) > mmc_claim_host(host); > if (mmc_card_is_sleep(host->card)) { > err = mmc_card_awake(host); > - mmc_card_clr_sleep(host->card); Without this patch, this was the suspend sequence/resume sequence for MMC cards: mmc_suspend_host() -> host->bus_ops->suspend() -> mmc_suspend() -> mmc_card_can_sleep() -> mmc_card_sleep() -> mmc_card_set_sleep() -> mmc_power_off() -> mmc_card_is_sleep(host->card) -> host->bus_ops->resume() -> mmc_resume() -> mmc_card_is_sleep() -> mmc_card_awake() -> mmc_card_clr_sleep() mmc_resume_host() -> mmc_power_up() -> This sets the buswidth=1, timing=legacy and clock=f_init -> host->bus_ops->resume() -> mmc_resume() -> mmc_card_is_sleep() -> this would return false because in mmc_suspend_host(), host->bus_ops->resume() call had cleared the sleep flag. -> mmc_init_card() -> As card sleep state is cleared, init_card() will be done which sets up the card again. But with this patch, you have removed the "host->bus_ops->resume()" call from mmc_power_off() which would mean card sleep state would be set to MMC_STATE_SLEEP during mmc_resume_host(). Following is the sequence with this patch: mmc_suspend_host() -> host->bus_ops->suspend() -> mmc_suspend() -> mmc_card_can_sleep() -> mmc_card_sleep() -> mmc_card_set_sleep() -> mmc_power_off() mmc_resume_host() -> mmc_power_up() -> This sets the bus_width=1, timing=legacy and clock=f_init -> host->bus_ops->resume() -> mmc_resume() -> mmc_card_is_sleep() -> this would return true because card sleep flag is set. -> mmc_card_awake() Block read/write operation: -> mmc_blk_issue_rw_rq -> send CMD25 -> But at this point, bus_width=1, timing=legacy and clock=f_init. Which is causing card not to respond back to data blocks sent from card and we are seeing the data timeout errors. So basically to fix this, in mmc_resume() either you have to call mmc_init_card() instead of mmc_card_awake() or if we still want to just call the mmc_card_awake() from resume, we need to save the state of host->ios before the sleep command issue so during resume, before calling mmc_awake(), we need to restore the saved host->ios state back and call mmc_set_ios() to restore the original parameters. Also, I couple of other concerns here: In mmc_suspend_host(), after we put the card into suspend (host->bus_ops_suspend()), we call mmc_power_off() which asks the host controller to switch off the eMMC power. Now assume that a particular host controller driver turns off both VCC and VCCQ rails when ios.power_mode = MMC_POWER_OFF. Now in mmc_resume_host(), we call mmc_power_up() which would switch ON the power back which would mean eMMC card have seen power down and power up sequence and that means card is no longer in sleep state. And now after mmc_power_up(), when we call the mmc_card_awake() from mmc_resume(), card may not even respond to CMD5 awake. So in this scenario, we should actually call mmc_init_card() to bring the card back to proper state. Regards, Subhash > } else > err = mmc_init_card(host, host->ocr, host->card); > mmc_release_host(host); > @@ -1407,6 +1445,7 @@ 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 = { @@ -1418,6 +1457,7 > @@ 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/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index > 1532357..463130f 100644 > --- a/drivers/mmc/host/dw_mmc.c > +++ b/drivers/mmc/host/dw_mmc.c > @@ -1788,11 +1788,6 @@ static int __init dw_mci_init_slot(struct dw_mci > *host, unsigned int id) > if (host->pdata->quirks & DW_MCI_QUIRK_HIGHSPEED) > mmc->caps |= MMC_CAP_SD_HIGHSPEED | > MMC_CAP_MMC_HIGHSPEED; > > - if (mmc->caps2 & MMC_CAP2_POWEROFF_NOTIFY) > - mmc->power_notify_type = MMC_HOST_PW_NOTIFY_SHORT; > - else > - mmc->power_notify_type = MMC_HOST_PW_NOTIFY_NONE; > - > if (host->pdata->blk_settings) { > mmc->max_segs = host->pdata->blk_settings->max_segs; > mmc->max_blk_size = host->pdata->blk_settings- > >max_blk_size; > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index > e626732..c0a5a91 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -2812,15 +2812,6 @@ int sdhci_add_host(struct sdhci_host *host) > if (caps[1] & SDHCI_DRIVER_TYPE_D) > mmc->caps |= MMC_CAP_DRIVER_TYPE_D; > > - /* > - * If Power Off Notify capability is enabled by the host, > - * set notify to short power off notify timeout value. > - */ > - if (mmc->caps2 & MMC_CAP2_POWEROFF_NOTIFY) > - mmc->power_notify_type = MMC_HOST_PW_NOTIFY_SHORT; > - else > - mmc->power_notify_type = MMC_HOST_PW_NOTIFY_NONE; > - > /* Initial value for re-tuning timer count */ > host->tuning_count = (caps[1] & > SDHCI_RETUNING_TIMER_COUNT_MASK) >> > SDHCI_RETUNING_TIMER_COUNT_SHIFT; diff --git > a/include/linux/mmc/card.h b/include/linux/mmc/card.h index > d76513b..040eec4 100644 > --- a/include/linux/mmc/card.h > +++ b/include/linux/mmc/card.h > @@ -239,11 +239,10 @@ struct mmc_card { > #define MMC_QUIRK_BROKEN_BYTE_MODE_512 (1<<8) /* Avoid > sending 512 bytes in */ > #define MMC_QUIRK_LONG_READ_TIME (1<<9) /* Data read > time > CSD says */ > /* byte mode */ > - unsigned int poweroff_notify_state; /* eMMC4.5 notify feature */ > + unsigned int poweroff_notify_state; /* MMC-4.5 poweroff > + notify feature */ > #define MMC_NO_POWER_NOTIFICATION 0 > #define MMC_POWERED_ON 1 > -#define MMC_POWEROFF_SHORT 2 > -#define MMC_POWEROFF_LONG 3 > > unsigned int erase_size; /* erase size in sectors */ > unsigned int erase_shift; /* if erase unit is power 2 */ > diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index > 1b431c7..54894d6 100644 > --- a/include/linux/mmc/core.h > +++ b/include/linux/mmc/core.h > @@ -161,6 +161,7 @@ extern int mmc_can_trim(struct mmc_card *card); > extern int mmc_can_discard(struct mmc_card *card); extern int > mmc_can_sanitize(struct mmc_card *card); extern int > mmc_can_secure_erase_trim(struct mmc_card *card); > +extern int mmc_can_poweroff_notify(const struct mmc_card *card); > extern int mmc_erase_group_aligned(struct mmc_card *card, unsigned int > from, > unsigned int nr); > extern unsigned int mmc_calc_max_discard(struct mmc_card *card); diff --git > a/include/linux/mmc/host.h b/include/linux/mmc/host.h index > 0707d22..0e9adac 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -238,12 +238,9 @@ 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; > -#define MMC_HOST_PW_NOTIFY_NONE 0 > -#define MMC_HOST_PW_NOTIFY_SHORT 1 > -#define MMC_HOST_PW_NOTIFY_LONG 2 > > #ifdef CONFIG_MMC_CLKGATE > int clk_requests; /* internal reference counter > */ > diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h index > d425cab..b11876b 100644 > --- a/include/linux/mmc/mmc.h > +++ b/include/linux/mmc/mmc.h > @@ -386,4 +386,11 @@ struct _mmc_csd { > #define MMC_SWITCH_MODE_CLEAR_BITS 0x02 /* Clear bits which are > 1 in value */ > #define MMC_SWITCH_MODE_WRITE_BYTE 0x03 /* Set target to value > */ > > +/* > + * MMC Poweroff Notify types > + */ > +#define MMC_PW_OFF_NOTIFY_NONE 0 > +#define MMC_PW_OFF_NOTIFY_SHORT 1 > +#define MMC_PW_OFF_NOTIFY_LONG 2 > + > #endif /* LINUX_MMC_MMC_H */ > -- > 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
