Messages in this thread | | | From | 吳昊澄 Ricky <> | Subject | RE: [PATCH 1/2] mmc: rtsx: add delay before power on | Date | Wed, 13 Jan 2021 10:20:42 +0000 |
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> On Wed, 30 Dec 2020 at 10:04, <ricky_wu@realtek.com> wrote: > > > > From: Ricky Wu <ricky_wu@realtek.com> > > > > Make sure voltage below 0.5V before power on when do power cycle > > > > Signed-off-by: Ricky Wu <ricky_wu@realtek.com> > > --- > > drivers/mmc/host/rtsx_pci_sdmmc.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c > > b/drivers/mmc/host/rtsx_pci_sdmmc.c > > index e6f5bbce5685..d21b99962b36 100644 > > --- a/drivers/mmc/host/rtsx_pci_sdmmc.c > > +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c > > @@ -906,6 +906,8 @@ static int sd_power_on(struct realtek_pci_sdmmc > *host) > > if (host->power_state == SDMMC_POWER_ON) > > return 0; > > > > + mdelay(100); > > + > > Why exactly 100 ms? Can you at least add a comment about why in the code? > > Moreover, I think you should convert to use msleep() rather than mdelay. >
Because we need to make sure voltage below 0.5V before power on mmc-core will do quickly power cycle at recognition card phase, we need at least 100ms to make our device voltage below 0.5V
I will change mdelay() to msleep()
> > rtsx_pci_init_cmd(pcr); > > rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, CARD_SELECT, 0x07, > SD_MOD_SEL); > > rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, CARD_SHARE_MODE, > > -- > > 2.17.1 > > > > Kind regards > Uffe > > ------Please consider the environment before printing this e-mail.
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