From mboxrd@z Thu Jan 1 00:00:00 1970 From: Javier Martinez Canillas Subject: Re: [PATCH v9 1/2] regulator: Add driver for max77802 PMIC PMIC regulators Date: Mon, 25 Aug 2014 11:07:08 +0200 Message-ID: <53FAFCBC.2050407@collabora.co.uk> References: <1408350762-15520-1-git-send-email-javier.martinez@collabora.co.uk> <1408350762-15520-2-git-send-email-javier.martinez@collabora.co.uk> <53F73472.8010609@collabora.co.uk> <20140822144531.GV24407@sirena.org.uk> <53F7838F.8060906@collabora.co.uk> <20140822183054.GY24407@sirena.org.uk> <53F7BDD8.7060500@collabora.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-samsung-soc-owner@vger.kernel.org To: Yuvaraj Cd , Doug Anderson Cc: Mark Brown , Olof Johansson , "devicetree@vger.kernel.org" , linux-samsung-soc , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Abhilash Kesavan , Prashanth G , Alim Akhtar , sunil joshi List-Id: devicetree@vger.kernel.org Hello Yuvaraj, On 08/25/2014 10:22 AM, Yuvaraj Cd wrote: >>> Good question. I'm not that familiar with the dw_mmc host controller nor >>> its driver implementation so I'll let Yuvaraj or Doug to answer that. > Well,here it goes! > 1. Power ON the board LDO4CTRL1[7:6] 11b > 2. dw_mmc driver enable the vqmmc. > 3. checks for UHS support, complete the voltage switching t0 1.8V > 4. Does warm reset by reboot command. > 5. mmc core calls mmc_set_ios() with MMC_POWER_OFF. > 6. dw_mmc driver cut-off the regulator with LDO4CTRL1[7:6] is 00b > 7.dw_mmc driver enable the vqmmc. > But after step 7 also, LD4CTRL[7:6] is 00b. Ok, so the dw_mmc driver is enabling vqmmc, that's good. >> >> I haven't seen the issue that Yuvaraj is reporting (but I also haven't >> picked up all of the relevant patches and tried to reproduce), so I'm >> going to have to leave it to Yuvaraj to answer. > static int max77802_enable(struct regulator_dev *rdev) > { > struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev); > int id = rdev_get_id(rdev); > int shift = max77802_get_opmode_shift(id); > return regmap_update_bits(rdev->regmap, > rdev->desc->enable_reg,rdev->desc->enable_mask,max77802->opmode[id] << > shift); > } > I think in the above code snippet, the "val" is what we got it during > the probe.We always write that value for enabling this regulator(which > is LDO4CTRL1[7:6] 00b after warm reset) which is not correct according > the MAX77802 manual. >> I see, so probably until we have a way to define the operating mode for each regulator using DT we should set the opmode to normal when enabling a regulator independently of the value the hardware register reported on probe. Can you please test the following change [0] so I can post as a proper patch? Doug, Mark do you think that forcing the regulator to opmode normal when enabling is the right solution here? Best regards, Javier [0] diff --git a/drivers/regulator/max77802.c b/drivers/regulator/max77802.c index ad1caa9..917b5ab 100644 --- a/drivers/regulator/max77802.c +++ b/drivers/regulator/max77802.c @@ -180,7 +180,7 @@ static int max77802_enable(struct regulator_dev *rdev) return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg, rdev->desc->enable_mask, - max77802->opmode[id] << shift); + MAX77802_OPMODE_NORMAL << shift); }