Hi Nicolas, > -----Original Message----- > From: Nicolas Pitre [mailto:nico@xxxxxxxxxxx] > Sent: Tuesday, September 07, 2010 6:29 PM > To: Bing Zhao > Cc: linux-mmc@xxxxxxxxxxxxxxx; Michal Miroslaw; Chris Ball; Andrew Morton > Subject: RE: [PATCH v2] sdio: skip initialization on powered resume > > On Tue, 7 Sep 2010, Bing Zhao wrote: > > > Thanks for the hint. > > > > The new patch skips reading CCCR, common CIS, and validation of > > vendor/device IDs inside mmc_sdio_init_card() when powered_resume is > > not zero. > > Why do you skip the reading of the CIS and IDs validation? That's > basically the main reason for still calling mmc_sdio_init_card(). And > that only requires CMD 52 so that should be fine. While the system is suspended, the SDIO card could be in sleep mode (deep sleep or IEEE Power Save) as well. Reading CIS or any other CMD52 will fail if the card happens to be in sleep at this moment. If we skip re-initialization (including CCCR/CIS and IDs validation), mmc_sdio_init_card() returns success. Then the client driver's resume() handler will be called and the card can be woken up by client driver. Regards, Bing > > > Nicolas -- 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
