* [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 @ 2012-04-23 9:11 Seungwon Jeon 2012-04-24 8:12 ` Subhash Jadavani 0 siblings, 1 reply; 4+ messages in thread From: Seungwon Jeon @ 2012-04-23 9:11 UTC (permalink / raw) To: linux-mmc; +Cc: 'Chris Ball', 'Girish K S' Currently only 1.2V is treated for HS200 mode. If the host has only 1.8V I/O capability not 1.2V, mmc_set_signal_voltage can't be called for 1.8V HS200. EXT_CSD_CARD_TYPE_SDR_1_8V needs to be considered. Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com> --- drivers/mmc/core/mmc.c | 12 +++++++----- 1 files changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index ebb9522..71eb320 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -732,7 +732,7 @@ static int mmc_select_powerclass(struct mmc_card *card, */ static int mmc_select_hs200(struct mmc_card *card) { - int idx, err = 0; + int idx, err = -EINVAL; struct mmc_host *host; static unsigned ext_csd_bits[] = { EXT_CSD_BUS_WIDTH_4, @@ -748,10 +748,12 @@ static int mmc_select_hs200(struct mmc_card *card) host = card->host; if (card->ext_csd.card_type & EXT_CSD_CARD_TYPE_SDR_1_2V && - host->caps2 & MMC_CAP2_HS200_1_2V_SDR) - if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120, 0)) - err = mmc_set_signal_voltage(host, - MMC_SIGNAL_VOLTAGE_180, 0); + host->caps2 & MMC_CAP2_HS200_1_2V_SDR) + err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120, 0); + + if (err && card->ext_csd.card_type & EXT_CSD_CARD_TYPE_SDR_1_8V && + host->caps2 & MMC_CAP2_HS200_1_8V_SDR) + err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180, 0); /* If fails try again during next card power cycle */ if (err) -- 1.7.0.4 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 2012-04-23 9:11 [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 Seungwon Jeon @ 2012-04-24 8:12 ` Subhash Jadavani 2012-04-25 5:15 ` Seungwon Jeon 0 siblings, 1 reply; 4+ messages in thread From: Subhash Jadavani @ 2012-04-24 8:12 UTC (permalink / raw) To: Seungwon Jeon; +Cc: linux-mmc, 'Chris Ball', 'Girish K S' Hi Seungwon, On 4/23/2012 2:41 PM, Seungwon Jeon wrote: > Currently only 1.2V is treated for HS200 mode. If the host has > only 1.8V I/O capability not 1.2V, mmc_set_signal_voltage can't > be called for 1.8V HS200. EXT_CSD_CARD_TYPE_SDR_1_8V needs to be > considered. Commit text looks confusing to me. In this change, you are trying to set the 1.8V I/O voltage only if there is an error setting the 1.2v I/O? Can you please clarify more? > > Signed-off-by: Seungwon Jeon<tgih.jun@samsung.com> > --- > drivers/mmc/core/mmc.c | 12 +++++++----- > 1 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index ebb9522..71eb320 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -732,7 +732,7 @@ static int mmc_select_powerclass(struct mmc_card *card, > */ > static int mmc_select_hs200(struct mmc_card *card) > { > - int idx, err = 0; > + int idx, err = -EINVAL; > struct mmc_host *host; > static unsigned ext_csd_bits[] = { > EXT_CSD_BUS_WIDTH_4, > @@ -748,10 +748,12 @@ static int mmc_select_hs200(struct mmc_card *card) > host = card->host; > > if (card->ext_csd.card_type& EXT_CSD_CARD_TYPE_SDR_1_2V&& > - host->caps2& MMC_CAP2_HS200_1_2V_SDR) > - if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120, 0)) > - err = mmc_set_signal_voltage(host, > - MMC_SIGNAL_VOLTAGE_180, 0); > + host->caps2& MMC_CAP2_HS200_1_2V_SDR) > + err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120, 0); > + > + if (err&& card->ext_csd.card_type& EXT_CSD_CARD_TYPE_SDR_1_8V&& > + host->caps2& MMC_CAP2_HS200_1_8V_SDR) > + err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180, 0); > > /* If fails try again during next card power cycle */ > if (err) ^ permalink raw reply [flat|nested] 4+ messages in thread
* RE: [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 2012-04-24 8:12 ` Subhash Jadavani @ 2012-04-25 5:15 ` Seungwon Jeon 2012-04-25 6:24 ` Subhash Jadavani 0 siblings, 1 reply; 4+ messages in thread From: Seungwon Jeon @ 2012-04-25 5:15 UTC (permalink / raw) To: 'Subhash Jadavani' Cc: linux-mmc, 'Chris Ball', 'Girish K S' Subhash Jadavani <subhashj@codeaurora.org> wrote: > Hi Seungwon, > > On 4/23/2012 2:41 PM, Seungwon Jeon wrote: > > Currently only 1.2V is treated for HS200 mode. If the host has > > only 1.8V I/O capability not 1.2V, mmc_set_signal_voltage can't > > be called for 1.8V HS200. EXT_CSD_CARD_TYPE_SDR_1_8V needs to be > > considered. > Commit text looks confusing to me. In this change, you are trying to set > the 1.8V I/O voltage only if there is an error setting the 1.2v I/O? Can > you please clarify more? This patch's purpose is to support 1.8V I/O. Origin considers only 1.2V I/O case. If the host has only 1.8V capability and card type is HS200 1.8V, there is no way to 1.8V I/O. Assuming that card is type of HS200 1.2V and host has 1.2V capability, the 1.2 I/O voltage will be tried. If it succeeds in 1.2V I/O , we don't need to trying the 1.8V I/O voltage though 1.8V I/O is possible. But the 1.8V I/O may be tried in case of 1.2V I/O failure, so error condition is needed. And error is initialized by -EINVAL at the first time. Thus, if card and host only are capable of 1.8V I/O, we can try to set the 1.8V I/O regardless of 1.2V I/O result. Best regards, Seungwon Jeon. > > > > Signed-off-by: Seungwon Jeon<tgih.jun@samsung.com> > > --- > > drivers/mmc/core/mmc.c | 12 +++++++----- > > 1 files changed, 7 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > > index ebb9522..71eb320 100644 > > --- a/drivers/mmc/core/mmc.c > > +++ b/drivers/mmc/core/mmc.c > > @@ -732,7 +732,7 @@ static int mmc_select_powerclass(struct mmc_card *card, > > */ > > static int mmc_select_hs200(struct mmc_card *card) > > { > > - int idx, err = 0; > > + int idx, err = -EINVAL; > > struct mmc_host *host; > > static unsigned ext_csd_bits[] = { > > EXT_CSD_BUS_WIDTH_4, > > @@ -748,10 +748,12 @@ static int mmc_select_hs200(struct mmc_card *card) > > host = card->host; > > > > if (card->ext_csd.card_type& EXT_CSD_CARD_TYPE_SDR_1_2V&& > > - host->caps2& MMC_CAP2_HS200_1_2V_SDR) > > - if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120, 0)) > > - err = mmc_set_signal_voltage(host, > > - MMC_SIGNAL_VOLTAGE_180, 0); > > + host->caps2& MMC_CAP2_HS200_1_2V_SDR) > > + err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120, 0); > > + > > + if (err&& card->ext_csd.card_type& EXT_CSD_CARD_TYPE_SDR_1_8V&& > > + host->caps2& MMC_CAP2_HS200_1_8V_SDR) > > + err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180, 0); > > > > /* If fails try again during next card power cycle */ > > if (err) > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 4+ messages in thread
* RE: [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 2012-04-25 5:15 ` Seungwon Jeon @ 2012-04-25 6:24 ` Subhash Jadavani 0 siblings, 0 replies; 4+ messages in thread From: Subhash Jadavani @ 2012-04-25 6:24 UTC (permalink / raw) To: 'Seungwon Jeon' Cc: linux-mmc, 'Chris Ball', 'Girish K S' > -----Original Message----- > From: Seungwon Jeon [mailto:tgih.jun@samsung.com] > Sent: Wednesday, April 25, 2012 10:46 AM > To: 'Subhash Jadavani' > Cc: linux-mmc@vger.kernel.org; 'Chris Ball'; 'Girish K S' > Subject: RE: [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 > > Subhash Jadavani <subhashj@codeaurora.org> wrote: > > Hi Seungwon, > > > > On 4/23/2012 2:41 PM, Seungwon Jeon wrote: > > > Currently only 1.2V is treated for HS200 mode. If the host has only > > > 1.8V I/O capability not 1.2V, mmc_set_signal_voltage can't be called > > > for 1.8V HS200. EXT_CSD_CARD_TYPE_SDR_1_8V needs to be considered. > > Commit text looks confusing to me. In this change, you are trying to > > set the 1.8V I/O voltage only if there is an error setting the 1.2v > > I/O? Can you please clarify more? > This patch's purpose is to support 1.8V I/O. Origin considers only 1.2V I/O case. > If the host has only 1.8V capability and card type is HS200 1.8V, there is no way > to 1.8V I/O. Thanks for clarification. I was assuming that most of the devices will have I/O voltage always set to 1.8v by host (when device is powered up) but yes, according to spec, it's possible that I/O may be at 3.3v (high voltage) as well. This patch looks good to me. Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org> Regards, Subhash > > Assuming that card is type of HS200 1.2V and host has 1.2V capability, the 1.2 > I/O voltage will be tried. If it succeeds in 1.2V I/O , we don't need to trying the > 1.8V I/O voltage though 1.8V I/O is possible. > But the 1.8V I/O may be tried in case of 1.2V I/O failure, so error condition is > needed. > > And error is initialized by -EINVAL at the first time. > Thus, if card and host only are capable of 1.8V I/O, we can try to set the 1.8V > I/O regardless of 1.2V I/O result. > > Best regards, > Seungwon Jeon. > > > > > > > Signed-off-by: Seungwon Jeon<tgih.jun@samsung.com> > > > --- > > > drivers/mmc/core/mmc.c | 12 +++++++----- > > > 1 files changed, 7 insertions(+), 5 deletions(-) > > > > > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index > > > ebb9522..71eb320 100644 > > > --- a/drivers/mmc/core/mmc.c > > > +++ b/drivers/mmc/core/mmc.c > > > @@ -732,7 +732,7 @@ static int mmc_select_powerclass(struct mmc_card > *card, > > > */ > > > static int mmc_select_hs200(struct mmc_card *card) > > > { > > > - int idx, err = 0; > > > + int idx, err = -EINVAL; > > > struct mmc_host *host; > > > static unsigned ext_csd_bits[] = { > > > EXT_CSD_BUS_WIDTH_4, > > > @@ -748,10 +748,12 @@ static int mmc_select_hs200(struct mmc_card > *card) > > > host = card->host; > > > > > > if (card->ext_csd.card_type& EXT_CSD_CARD_TYPE_SDR_1_2V&& > > > - host->caps2& MMC_CAP2_HS200_1_2V_SDR) > > > - if (mmc_set_signal_voltage(host, > MMC_SIGNAL_VOLTAGE_120, 0)) > > > - err = mmc_set_signal_voltage(host, > > > - > MMC_SIGNAL_VOLTAGE_180, 0); > > > + host->caps2& MMC_CAP2_HS200_1_2V_SDR) > > > + err = mmc_set_signal_voltage(host, > MMC_SIGNAL_VOLTAGE_120, 0); > > > + > > > + if (err&& card->ext_csd.card_type& > EXT_CSD_CARD_TYPE_SDR_1_8V&& > > > + host->caps2& MMC_CAP2_HS200_1_8V_SDR) > > > + err = mmc_set_signal_voltage(host, > MMC_SIGNAL_VOLTAGE_180, 0); > > > > > > /* If fails try again during next card power cycle */ > > > if (err) > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-mmc" > > in the body of a message to majordomo@vger.kernel.org More majordomo > > info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2012-04-25 6:24 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2012-04-23 9:11 [PATCH 2/2] mmc: core: fix the signaling 1.8V for HS200 Seungwon Jeon 2012-04-24 8:12 ` Subhash Jadavani 2012-04-25 5:15 ` Seungwon Jeon 2012-04-25 6:24 ` Subhash Jadavani
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