From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH v3] mmc: host: sdhci-sprd: Fix the incorrect soft reset operation when runtime resuming Date: Tue, 16 Jul 2019 13:39:37 +0300 Message-ID: <07e348a0-6a80-e176-d18d-6a1e54313fa6@intel.com> References: <7ab490e5b311f6cb057c4663d69ef7cbe3318dae.1563266066.git.baolin.wang@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <7ab490e5b311f6cb057c4663d69ef7cbe3318dae.1563266066.git.baolin.wang@linaro.org> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Baolin Wang , ulf.hansson@linaro.org, zhang.lyra@gmail.com, orsonzhai@gmail.com Cc: vincent.guittot@linaro.org, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-mmc@vger.kernel.org On 16/07/19 11:39 AM, Baolin Wang wrote: > In sdhci_runtime_resume_host() function, we will always do software reset > for all, which will cause Spreadtrum host controller work abnormally after > resuming. > > Thus for Spreadtrum platform that do not power down the SD/eMMC card during > runtime suspend, we should not do software reset for all. To fix this > issue, adding a specific reset operation that add one condition to validate > the MMC_CAP_AGGRESSIVE_PM to decide if we can do software reset for all or > just reset command and data lines. > > Signed-off-by: Baolin Wang > --- > Changes from v2: > - Simplify the sdhci_sprd_reset() by issuing sdhci_reset(). > > Changes from v1: > - Add a specific reset operation instead of changing the core to avoid > affecting other hardware. > --- > drivers/mmc/host/sdhci-sprd.c | 19 ++++++++++++++++++- > 1 file changed, 18 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c > index 603a5d9..bc9393c 100644 > --- a/drivers/mmc/host/sdhci-sprd.c > +++ b/drivers/mmc/host/sdhci-sprd.c > @@ -373,6 +373,23 @@ static unsigned int sdhci_sprd_get_max_timeout_count(struct sdhci_host *host) > return 1 << 31; > } > > +static void sdhci_sprd_reset(struct sdhci_host *host, u8 mask) > +{ > + struct mmc_host *mmc = host->mmc; > + > + /* > + * When try to reset controller after runtime suspend, we should not > + * reset for all if the SD/eMMC card is not power down, just reset > + * command and data lines instead. Otherwise will meet some strange > + * behaviors for Spreadtrum host controller. > + */ > + if (host->runtime_suspended && (mask & SDHCI_RESET_ALL) && > + !(mmc->caps & MMC_CAP_AGGRESSIVE_PM)) MMC_CAP_AGGRESSIVE_PM does not necessarily mean that the card will have been runtime suspended. What about checking if the card power is on? i.e. if (host->runtime_suspended && (mask & SDHCI_RESET_ALL) && mmc->ios.power_mode == MMC_POWER_ON) > + mask = SDHCI_RESET_CMD | SDHCI_RESET_DATA; > + > + sdhci_reset(host, mask); > +} > + > static struct sdhci_ops sdhci_sprd_ops = { > .read_l = sdhci_sprd_readl, > .write_l = sdhci_sprd_writel, > @@ -381,7 +398,7 @@ static unsigned int sdhci_sprd_get_max_timeout_count(struct sdhci_host *host) > .get_max_clock = sdhci_sprd_get_max_clock, > .get_min_clock = sdhci_sprd_get_min_clock, > .set_bus_width = sdhci_set_bus_width, > - .reset = sdhci_reset, > + .reset = sdhci_sprd_reset, > .set_uhs_signaling = sdhci_sprd_set_uhs_signaling, > .hw_reset = sdhci_sprd_hw_reset, > .get_max_timeout_count = sdhci_sprd_get_max_timeout_count, >