2013/2/27 Chris Ball <cjb@xxxxxxxxxx>: > Hi, > > The CC: list seems excessively long here. > > On Wed, Feb 27 2013, Kevin Liu wrote: >> Who can help to answer below question? >> Which statement is true if quirk SDHCI_QUIRK_BROKEN_CARD_DETECTION is selected? >> 1. The host controller Present State Register[18] (offset 0x24) can >> reflect card status (present or not) but can't trigger interrupt when >> card insert/remove. >> 2. The host controller Present State Register[18] can't reflect card >> status at all and can't trigger card insert/remove interrupt either. >> But have other way out of host controller to detect card like slot >> gpio. >> 3. The host controller Present State Register[18] can't reflect card >> status at all, can't trigger card insert/remove interrupt, and don't >> have the other ways to detect card like slot gpio. So have to use >> polling to know card present status. > > (3) > > The best documentation for this is probably the DT bindings file: > > Card detection: > If no property below is supplied, host native card detect is used. > Only one of the properties in this section should be supplied: > - broken-cd: There is no card detection available; polling must be used. > - cd-gpios: Specify GPIOs for card detection, see gpio binding > - non-removable: non-removable slot (like eMMC); assume always present. > > (SDHCI_QUIRK_BROKEN_CARD_DETECTION maps to broken-cd) > Chris, Thanks for quick answer! Then if broken-cd/SDHCI_QUIRK_BROKEN_CARD_DETECTION is selected, can I use host controller Present State Register[18] (offset 0x24) to know card status (present or not)? Kevin > - Chris. > -- > Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/> > One Laptop Per Child -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
