> -----Original Message----- > From: Nicolas Pitre [mailto:nico@xxxxxxxxxxx] > Sent: Wednesday, July 07, 2010 9:03 AM > To: Roger Quadros > Cc: Hunter Adrian (Nokia-MS/Helsinki); Ohad Ben-Cohen; linux- > wireless@xxxxxxxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx; linux- > omap@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > linux@xxxxxxxxxxxxxxxx; Chikkature Rajashekar Madhusudhan; Coelho Luciano > (Nokia-MS/Helsinki); akpm@xxxxxxxxxxxxxxxxxxxx; San Mehat > Subject: Re: [PATCH 11/15] wireless: wl1271: introduce platform device > support > > On Wed, 7 Jul 2010, Roger Quadros wrote: > > > On 07/06/2010 10:51 PM, Hunter Adrian (Nokia-MS/Helsinki) wrote: > > > For eMMC in omap_hsmmc, this is all done via claim_host / release_host > > > which call ->enable() / ->disable() methods. omap_hsmmc makes use of > > > mmc_power_restore_host() which calls host->bus_ops->power_restore() > > > which is not implemented for SDIO, but for MMC and SD it reinitializes > > > the card. > > This is IMHO a really bad design. The power control decision has to > come from the top, not from the bottom. And certainly not with a > U-turn dependency the omap_hsmmc is using. > > I regret to say this, but the omap_hsmmc driver is becoming a total > mess. The host controller driver has to be a dumb interface serving > requests from the hardware used by the upper layer stack, not the place > where decisions such as power handling should be made. Think of it like > an ethernet driver. No ethernet driver in Linux is telling the IP stack > when to shut down. > The point is that MMC/SD core files were patched to provide this kind of a support. Any controller driver can use that framework today, right?. As an example omap_hsmmc driver was patched and it works fine. Why blame the controller driver for using a support provided by core files? Regards, Madhu > > Shouldn't the power control intelligence (i.e. when to turn power > ON/OFF) lie > > with the bus drivers? > > Absolutely! And in the SDIO case that should lie with each function > drivers. Please let's stop this omap_hsmmc madness. > > > Nicolas -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
