From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Vrabel Subject: Re: [PATCH 3/3] mmc: omap_hsmmc: enable SDIO card interrupts Date: Wed, 17 Feb 2010 19:39:52 +0000 Message-ID: <4B7C4608.5010008@csr.com> References: <846fbf1a68cde5fd2d7c7ab084ace239c8de6867.1265801967.git.david.vrabel@csr.com> <9ce6cf93ba1e6c3fd239f732ea5889a856948db3.1265801967.git.david.vrabel@csr.com> <004901cab001$6b19f6c0$544ff780@am.dhcp.ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <004901cab001$6b19f6c0$544ff780@am.dhcp.ti.com> Sender: linux-mmc-owner@vger.kernel.org To: Madhusudhan Cc: linux-mmc@vger.kernel.org, linux-omap@vger.kernel.org List-Id: linux-omap@vger.kernel.org Madhusudhan wrote: > >> -----Original Message----- >> From: David Vrabel [mailto:david.vrabel@csr.com] >> Sent: Wednesday, February 10, 2010 5:52 AM >> To: linux-mmc@vger.kernel.org >> Cc: David Vrabel; linux-omap@vger.kernel.org; madhu.cr@ti.com >> Subject: [PATCH 3/3] mmc: omap_hsmmc: enable SDIO card interrupts >> >> Enable the use of SDIO card interrupts. This requires setting ENAWAKEUP >> in SYSCONFIG and IWE in HTCL to allow the MMC block to wake-up when in >> smart-idle mode. >> >> FCLK must be enabled while SDIO interrupts are enabled or the MMC block >> won't wake-up. >> > > I am curious to know the system behavior with this patch. Does the FCLK > remain enabled forever if a SDIO card is detected on the bus? Only if card interrupts are enabled. The card irq is disabled when the sdio_irq_thread exits. This is why I think that smart-idle mode needs to be used (it's turned on by default on the MMC controller) but I don't understand the clock/clockdomain code to see if that's doing the right thing. If smart-idle mode is used then we don't need to disable FCLK manually to save power. This will simplify the driver a bit. David