On Mon, 14 Mar 2022 at 10:53, Yann Gautier <yann.gautier@xxxxxxxxxxx> wrote: > > Add a disable_keep_power field in variant_data struct. The > MMC_PM_KEEP_POWER flag will be enabled if disable_keep_power is not set. > It is only set to true for stm32_sdmmc variants. > > The issue was seen on STM32MP157C-DK2 board, which embeds a wifi chip. > It doesn't correctly support low power, and we need to unbind the wifi > driver before a suspend sequence. But the wifi chip firmware is then > lost, and the communication with SDIO fails if MMC_PM_KEEP_POWER is > enabled. So the platform supports to maintain the power for the embedded wifi chip during system suspend, but the SDIO func driver (for the WiFi chip) doesn't implement its part correctly. Did I get that right? In that case, it sounds to me like we should try to fix the support for power management in the SDIO func driver instead, no? I am happy to help with guidance/review if that is needed. What SDIO func driver is this about? Kind regards Uffe > The flag can still be enabled through DT property: keep-power-in-suspend. > > Signed-off-by: Yann Gautier <yann.gautier@xxxxxxxxxxx> > --- > Resend the patch alone. It was previoulsy in a series [1] for which the > other patches will be reworked. > > [1] https://lore.kernel.org/lkml/20220304135134.47827-1-yann.gautier@xxxxxxxxxxx/ > > drivers/mmc/host/mmci.c | 5 ++++- > drivers/mmc/host/mmci.h | 1 + > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c > index 45b8608c935c..0e2f2f5d6a52 100644 > --- a/drivers/mmc/host/mmci.c > +++ b/drivers/mmc/host/mmci.c > @@ -274,6 +274,7 @@ static struct variant_data variant_stm32_sdmmc = { > .busy_detect = true, > .busy_detect_flag = MCI_STM32_BUSYD0, > .busy_detect_mask = MCI_STM32_BUSYD0ENDMASK, > + .disable_keep_power = true, > .init = sdmmc_variant_init, > }; > > @@ -301,6 +302,7 @@ static struct variant_data variant_stm32_sdmmcv2 = { > .busy_detect = true, > .busy_detect_flag = MCI_STM32_BUSYD0, > .busy_detect_mask = MCI_STM32_BUSYD0ENDMASK, > + .disable_keep_power = true, > .init = sdmmc_variant_init, > }; > > @@ -2172,7 +2174,8 @@ static int mmci_probe(struct amba_device *dev, > host->stop_abort.flags = MMC_RSP_R1B | MMC_CMD_AC; > > /* We support these PM capabilities. */ > - mmc->pm_caps |= MMC_PM_KEEP_POWER; > + if (!variant->disable_keep_power) > + mmc->pm_caps |= MMC_PM_KEEP_POWER; > > /* > * We can do SGIO > diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h > index e1a9b96a3396..2cad1ef9766a 100644 > --- a/drivers/mmc/host/mmci.h > +++ b/drivers/mmc/host/mmci.h > @@ -361,6 +361,7 @@ struct variant_data { > u32 opendrain; > u8 dma_lli:1; > u32 stm32_idmabsize_mask; > + u8 disable_keep_power:1; > void (*init)(struct mmci_host *host); > }; > > -- > 2.25.1 >
