Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751187AbdCNNHM (ORCPT ); Tue, 14 Mar 2017 09:07:12 -0400 Received: from exsmtp01.microchip.com ([198.175.253.37]:41449 "EHLO email.microchip.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750930AbdCNNHL (ORCPT ); Tue, 14 Mar 2017 09:07:11 -0400 Date: Tue, 14 Mar 2017 14:06:40 +0100 From: Ludovic Desroches To: Romain Izard CC: , , , Ludovic Desroches , Adrian Hunter , Ulf Hansson Subject: Re: [PATCH] mmc: sdhci-of-at91: Support external regulators Message-ID: <20170314130640.wz2wnebphaluvsjw@rfolt0960.corp.atmel.com> Mail-Followup-To: Romain Izard , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mmc@vger.kernel.org, Adrian Hunter , Ulf Hansson References: <20170309151820.7510-1-romain.izard.pro@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20170309151820.7510-1-romain.izard.pro@gmail.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2302 Lines: 64 On Thu, Mar 09, 2017 at 04:18:20PM +0100, Romain Izard wrote: > The SDHCI controller in the SAMA5D2 chip requires a valid voltage set > in the power control register, otherwise commands will fail with a > timeout error. > > When using the regulator framework to specify the regulator used by the > mmc device, the voltage is not configured, and it is not possible to use > the connected device. > > Implement a custom 'set_power' function for this specific hardware, that > configures the voltage in the register in all cases. > > Signed-off-by: Romain Izard Cc: stable@vger.kernel.org #4.9+ Can be added since sdhci_set_power_noreg was introduced in 4.9. > --- > drivers/mmc/host/sdhci-of-at91.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c > index 2f9ad213377a..291a74955a4c 100644 > --- a/drivers/mmc/host/sdhci-of-at91.c > +++ b/drivers/mmc/host/sdhci-of-at91.c > @@ -85,11 +85,30 @@ static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) > sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); > } > > +/* > + * In this specific implementation of the SDHCI contoller, the power register > + * needs to have a valid voltage set even when the power supply is managed by > + * an external regulator. > + */ > +static void sdhci_at91_set_power(struct sdhci_host *host, unsigned char mode, > + unsigned short vdd) > +{ > + if (!IS_ERR(host->mmc->supply.vmmc)) { > + struct mmc_host *mmc = host->mmc; > + > + spin_unlock_irq(&host->lock); > + mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd); > + spin_lock_irq(&host->lock); > + } > + sdhci_set_power_noreg(host, mode, vdd); > +} > + > static const struct sdhci_ops sdhci_at91_sama5d2_ops = { > .set_clock = sdhci_at91_set_clock, > .set_bus_width = sdhci_set_bus_width, > .reset = sdhci_reset, > .set_uhs_signaling = sdhci_set_uhs_signaling, > + .set_power = sdhci_at91_set_power, > }; > > static const struct sdhci_pltfm_data soc_data_sama5d2 = { > -- > 2.9.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html