Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753549AbcC3NPZ (ORCPT ); Wed, 30 Mar 2016 09:15:25 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:12277 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751425AbcC3NPX (ORCPT ); Wed, 30 Mar 2016 09:15:23 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Wed, 30 Mar 2016 06:14:06 -0700 Subject: Re: Tegra boots failing due to as3722 I/O errors To: Mark Brown , Laxman Dewangan , "Maciej S. Szmigiero" , Lee Jones , Stephen Warren , "Thierry Reding" , Alexandre Courbot References: <20160329190319.GE2350@sirena.org.uk> <56FBB923.4000302@nvidia.com> CC: , , "Liam Girdwood" From: Jon Hunter Message-ID: <56FBD164.7040707@nvidia.com> Date: Wed, 30 Mar 2016 14:15:16 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <56FBB923.4000302@nvidia.com> X-Originating-IP: [10.21.132.115] X-ClientProxiedBy: UKMAIL101.nvidia.com (10.26.138.13) To UKMAIL101.nvidia.com (10.26.138.13) Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3959 Lines: 85 Hi Mark, On 30/03/16 12:31, Jon Hunter wrote: > On 29/03/16 20:03, Mark Brown wrote: >> * PGP Signed by an unknown key >> >> Hi, >> >> Currently the Jetson TK1 is failing to get regulators for MMC with at >> least my regulator tree and probably -next also due to: >> >> [ 1.665750] as3722 4-0040: AS3722 with revision 0x1 found >> [ 1.682945] +VDDIO_SDMMC3: failed to get the current voltage(-22) >> [ 1.689135] as3722-regulator as3722-regulator: regulator 13 register failed -22 >> [ 1.697593] as3722-regulator: probe of as3722-regulator failed with error -22 >> >> The get voltage operation here is just a simple mapping of a bitfield in >> the regmap which suggests that the underlying problem is somewhere >> further down the stack like the MFD or I2C drivers. The error is >> -EINVAL which suggests something like the register not being marked as >> readable but the _VOLTAGE_REG registers appear to be marked as readable >> in the MFD. >> >> Full log for one boot at: >> >> https://storage.kernelci.org/broonie-regulator/v4.6-rc1-24-ga7e614dd1f91/arm-multi_v7_defconfig+CONFIG_SMP=n/lab-mhart/boot-tegra124-jetson-tk1.html > > Thanks for the report. I took a quick look at this and it turns out > that i2c and regmap are all working fine. The problem is the > VDDIO_SDMMC3 LDO (aka. LDO6) on the as3722 has a bypass mode which is > not represented by the voltage ranges for the LDO. On boot the LDO is > in bypass and returns a value which is not recognised and hence an > EINVAL is returned. The following change fixes the problem. The 0x3F > value represents the bypass mode. I will send out a formal patch. > > Cheers > Jon > > diff --git a/drivers/regulator/as3722-regulator.c b/drivers/regulator/as3722-regulator.c > index 8b046ee..f16d0e5 100644 > --- a/drivers/regulator/as3722-regulator.c > +++ b/drivers/regulator/as3722-regulator.c > @@ -438,6 +438,13 @@ static const struct regulator_linear_range as3722_ldo_ranges[] = { > REGULATOR_LINEAR_RANGE(1725000, 0x40, 0x7F, 25000), > }; > > +static const struct regulator_linear_range as3722_ldo6_ranges[] = { > + REGULATOR_LINEAR_RANGE(0, 0x00, 0x00, 0), > + REGULATOR_LINEAR_RANGE(825000, 0x01, 0x24, 25000), > + REGULATOR_LINEAR_RANGE(3300000, 0x3F, 0x3F, 0), > + REGULATOR_LINEAR_RANGE(1725000, 0x40, 0x7F, 25000), > +}; > + > static struct regulator_ops as3722_ldo_ops = { > .is_enabled = regulator_is_enabled_regmap, > .enable = regulator_enable_regmap, > @@ -863,6 +870,16 @@ static int as3722_regulator_probe(struct platform_device *pdev) > as3722_regs->desc[id].n_linear_ranges = > ARRAY_SIZE(as3722_sd2345_ranges); > break; > + case AS3722_REGULATOR_ID_LDO6: > + if (reg_config->ext_control) > + ops = &as3722_ldo_extcntrl_ops; > + else > + ops = &as3722_ldo_ops; > + as3722_regs->desc[id].enable_time = 500; > + as3722_regs->desc[id].linear_ranges = as3722_ldo6_ranges; > + as3722_regs->desc[id].n_linear_ranges = > + ARRAY_SIZE(as3722_ldo6_ranges); > + break; > default: > if (reg_config->ext_control) > ops = &as3722_ldo_extcntrl_ops; On second thoughts, is this the correct way to fix this? I see that there are some operators defined for get/set_bypass for a regulator and these are not specified for LDO6 either. However, even if they were I don't believe this will fix the problem alone. The failure is caused by _regulator_get_voltage() returning an error. This function does not check if the regulator is bypassed, but I am wondering if it should and then return the bypass voltage? Cheers Jon