| Message ID | 1453455902-3987-2-git-send-email-adrian.hunter@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 22 January 2016 at 10:45, Adrian Hunter <adrian.hunter@intel.com> wrote: > In the future sdhci will be a library. When that happens > a callback will be needed to allow drivers easily to override > the standard way of determining whether a card is present. There's already a ->get_cd() callback in the struct mmc_host_ops. By turning sdhci into a library, each sdhci variant should decide whether they want to use a default "sdhci_get_cd()" version, rely on slot-gpio or implement their own. I don't understand why we need a specific sdhci callback to deal with this, it doesn't make sense to me. > That is needed because functions like sdhci_request() also > check the card presence. Why does sdhci do that? Is that because some variants needs it or because of all? Reading a state of a GPIO pin before every request doesn't come without a cost in performance. My point is, it should only be done when *really* needed. Again, by having sdhci to become a library each variant should decide what's needed for them. > > The get_cd callback is being added now to facilitate > a bug fix, for which subsequent patches are provided. > > Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> > Cc: stable@vger.kernel.org # v4.4+ > --- > drivers/mmc/host/sdhci.c | 6 +++++- > drivers/mmc/host/sdhci.h | 1 + > 2 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index d622435d1bcc..535236084b27 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -1612,7 +1612,7 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) > > static int sdhci_do_get_cd(struct sdhci_host *host) > { > - int gpio_cd = mmc_gpio_get_cd(host->mmc); > + int gpio_cd; > > if (host->flags & SDHCI_DEVICE_DEAD) > return 0; > @@ -1621,10 +1621,14 @@ static int sdhci_do_get_cd(struct sdhci_host *host) > if (host->mmc->caps & MMC_CAP_NONREMOVABLE) > return 1; > > + if (host->ops->get_cd) > + return host->ops->get_cd(host); > + > /* > * Try slot gpio detect, if defined it take precedence > * over build in controller functionality > */ > + gpio_cd = mmc_gpio_get_cd(host->mmc); > if (!IS_ERR_VALUE(gpio_cd)) > return !!gpio_cd; > > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index 7654ae5d2b4e..a6c2cd8ef0b2 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -552,6 +552,7 @@ struct sdhci_ops { > struct mmc_card *card, > unsigned int max_dtr, int host_drv, > int card_drv, int *drv_type); > + int (*get_cd)(struct sdhci_host *host); > }; > > #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS > -- > 1.9.1 > Can you please try to fix this without adding a new callback!? I know, it requires some more efforts but for sure it's doable. Kind regards Uffe -- 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
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index d622435d1bcc..535236084b27 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1612,7 +1612,7 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) static int sdhci_do_get_cd(struct sdhci_host *host) { - int gpio_cd = mmc_gpio_get_cd(host->mmc); + int gpio_cd; if (host->flags & SDHCI_DEVICE_DEAD) return 0; @@ -1621,10 +1621,14 @@ static int sdhci_do_get_cd(struct sdhci_host *host) if (host->mmc->caps & MMC_CAP_NONREMOVABLE) return 1; + if (host->ops->get_cd) + return host->ops->get_cd(host); + /* * Try slot gpio detect, if defined it take precedence * over build in controller functionality */ + gpio_cd = mmc_gpio_get_cd(host->mmc); if (!IS_ERR_VALUE(gpio_cd)) return !!gpio_cd; diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index 7654ae5d2b4e..a6c2cd8ef0b2 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -552,6 +552,7 @@ struct sdhci_ops { struct mmc_card *card, unsigned int max_dtr, int host_drv, int card_drv, int *drv_type); + int (*get_cd)(struct sdhci_host *host); }; #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
In the future sdhci will be a library. When that happens a callback will be needed to allow drivers easily to override the standard way of determining whether a card is present. That is needed because functions like sdhci_request() also check the card presence. The get_cd callback is being added now to facilitate a bug fix, for which subsequent patches are provided. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org # v4.4+ --- drivers/mmc/host/sdhci.c | 6 +++++- drivers/mmc/host/sdhci.h | 1 + 2 files changed, 6 insertions(+), 1 deletion(-)