From mboxrd@z Thu Jan 1 00:00:00 1970 From: micky Subject: Re: [PATCH] mmc: rtsx: add card power off during probe Date: Wed, 17 Sep 2014 17:11:18 +0800 Message-ID: <54195036.2010409@realsil.com.cn> References: <1410485999-10939-1-git-send-email-micky_ching@realsil.com.cn> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" To: Ulf Hansson Cc: Samuel Ortiz , Greg Kroah-Hartman , linux-mmc , "linux-kernel@vger.kernel.org" , Chris Ball , Wei WANG , Roger , "driverdev-devel@linuxdriverproject.org" , Dan Carpenter List-Id: linux-mmc@vger.kernel.org On 09/17/2014 02:01 AM, Ulf Hansson wrote: > On 12 September 2014 03:39, wrote: >> From: Roger Tseng >> >> Some platform have both UEFI driver and MFD/mmc driver, if entering >> linux while card in the slot, the card power is already on, and rtsx-mmc >> driver have no chance to make card power off. This will lead UHSI card >> failed to enter UHSI mode. >> >> It is hard to control the UEFI driver leaving state, so we power off the >> card power during probe. >> >> Signed-off-by: Roger Tseng >> Signed-off-by: Micky Ching >> --- >> drivers/mmc/host/rtsx_pci_sdmmc.c | 7 ++++++- >> 1 file changed, 6 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c >> index dfde4a2..57b0796 100644 >> --- a/drivers/mmc/host/rtsx_pci_sdmmc.c >> +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c >> @@ -1341,8 +1341,13 @@ static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev) >> host->pcr = pcr; >> host->mmc = mmc; >> host->pdev = pdev; >> - host->power_state = SDMMC_POWER_OFF; >> INIT_WORK(&host->work, sd_request); >> + sd_power_off(host); >> + /* >> + * ref: SD spec 3.01: 6.4.1.2 Power On or Power Cycle >> + */ >> + usleep_range(1000, 2000); >> + > This won't work in cases were you power off eMMC cards, unless you can > do a full power cycle - cut both VCC and VCCQ. Can you? Hi Uffe, VCCQ will poweroff at the same time. if MMC_CAP2_NO_PRESCAN_POWERUP enable, will call mmc_power_off() at start, then it will check ios.power_mode, but the state is MMC_POWER_OFF and just return. Best Regards. micky. > There are also another option you might want to use, > MMC_CAP2_NO_PRESCAN_POWERUP. But again, it must only be used for those > hosts that you are able to do a full power cycle for. > > Kind regards > Uffe > >> platform_set_drvdata(pdev, host); >> pcr->slots[RTSX_SD_CARD].p_dev = pdev; >> pcr->slots[RTSX_SD_CARD].card_event = rtsx_pci_sdmmc_card_event; >> -- >> 1.7.9.5 >> > . >