From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: Re: [PATCH V2] MMC: PM: add suspend/resume in atmel-mci Date: Fri, 01 Jul 2011 16:22:14 +0200 Message-ID: <4E0DD816.7070104@atmel.com> References: <201106292339.12402.rjw@sisk.pl> <1309441781-11012-1-git-send-email-nicolas.ferre@atmel.com> <20110630131342.GK11559@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from newsmtp5.atmel.com ([204.2.163.5]:37940 "EHLO sjogate2.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756670Ab1GAOWs (ORCPT ); Fri, 1 Jul 2011 10:22:48 -0400 In-Reply-To: <20110630131342.GK11559@pengutronix.de> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: =?ISO-8859-1?Q?Uwe_Kleine-K=F6nig?= Cc: cjb@laptop.org, linux-mmc@vger.kernel.org, hans-christian.egtvedt@atmel.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@avr32linux.org Le 30/06/2011 15:13, Uwe Kleine-K=F6nig : > Hello Nicolas, >=20 > On Thu, Jun 30, 2011 at 03:49:41PM +0200, Nicolas Ferre wrote: >> Take care of slots while going to suspend state. >> >> Signed-off-by: Nicolas Ferre >> Signed-off-by: Uwe Kleine-K=F6nig >> --- >> V2: move to pm_ops >> >> drivers/mmc/host/atmel-mci.c | 47 +++++++++++++++++++++++++++++++= +++++++++++ >> 1 files changed, 47 insertions(+), 0 deletions(-) >> >> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-m= ci.c >> index aa8039f..058f1842 100644 >> --- a/drivers/mmc/host/atmel-mci.c >> +++ b/drivers/mmc/host/atmel-mci.c >> @@ -1878,10 +1878,57 @@ static int __exit atmci_remove(struct platfo= rm_device *pdev) >> return 0; >> } >> =20 >> +#ifdef CONFIG_PM >> +static int atmci_suspend(struct device *dev) >> +{ >> + struct atmel_mci *host =3D dev_get_drvdata(dev); >> + struct atmel_mci_slot *slot; >> + int i, ret; > slot and ret can have a more local scope. ok. >> + >> + for (i =3D 0; i < ATMEL_MCI_MAX_NR_SLOTS; i++) { >> + slot =3D host->slot[i]; >> + if (!slot) >> + continue; >> + ret =3D mmc_suspend_host(slot->mmc); >> + if (ret < 0) { >> + while (--i >=3D 0) { >> + slot =3D host->slot[i]; >> + if (slot) >> + mmc_resume_host(host->slot[i]->mmc); > hmm, mmc_resume_host could fail. But probably you cannot handle that = in > a sane way, do you? Well, actually for the current implementation the only return code is..= =2E 0. And here I try to have a king of best effort approach ;-) >> + } >> + return ret; >> + } >> + } >> + >> + return 0; >> +} >> + >> +static int atmci_resume(struct device *dev) >> +{ >> + struct atmel_mci *host =3D dev_get_drvdata(dev); >> + struct atmel_mci_slot *slot; >> + int i, ret; >> + >> + for (i =3D 0; i < ATMEL_MCI_MAX_NR_SLOTS; i++) { >> + slot =3D host->slot[i]; >> + if (!slot) >> + continue; >> + ret =3D mmc_resume_host(slot->mmc); >> + if (ret < 0) >> + return ret; > Maybe you should try to resume host 5 even if resuming host 4 failed? In fact all other drivers that are dealing with multiple slots are doin= g the same... So I have difficulties to know the truth. The question is: is it better to return an error to the "resume" function so that we are called later again or do we have to do our best to thaw everything out? >> + } >> + >> + return 0; >> +} >> +#endif >> +static SIMPLE_DEV_PM_OPS(atmci_pm, atmci_suspend, atmci_resume); >> + >> + > For my taste a single empty line is enough. Ok. >> static struct platform_driver atmci_driver =3D { >> .remove =3D __exit_p(atmci_remove), >> .driver =3D { >> .name =3D "atmel_mci", >> + .pm =3D &atmci_pm, >> }, >> }; >=20 Thanks, best regards, --=20 Nicolas Ferre