Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755227AbcCPFxv (ORCPT ); Wed, 16 Mar 2016 01:53:51 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:15371 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752531AbcCPFxt convert rfc822-to-8bit (ORCPT ); Wed, 16 Mar 2016 01:53:49 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Tue, 15 Mar 2016 22:53:00 -0700 Message-ID: <56E8F4F1.1060603@nvidia.com> Date: Wed, 16 Mar 2016 13:53:53 +0800 From: Wei Ni User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Eduardo Valentin CC: , , , , , , , Subject: Re: [PATCH V7 09/12] thermal: tegra: add thermtrip function References: <1457665872-30046-1-git-send-email-wni@nvidia.com> <20160314191637.GC1872@localhost.localdomain> <56E7D1EC.5090907@nvidia.com> <20160315194929.GB26619@localhost.localdomain> In-Reply-To: <20160315194929.GB26619@localhost.localdomain> X-Originating-IP: [10.19.224.146] X-ClientProxiedBy: DRBGMAIL104.nvidia.com (10.18.16.23) To HKMAIL101.nvidia.com (10.18.16.10) Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4711 Lines: 129 On 2016年03月16日 03:49, Eduardo Valentin wrote: > * PGP Signed by an unknown key > > On Tue, Mar 15, 2016 at 05:12:12PM +0800, Wei Ni wrote: >> >> >> On 2016年03月15日 03:16, Eduardo Valentin wrote: >>>> Old Signed by an unknown key >>> >>> On Fri, Mar 11, 2016 at 11:11:12AM +0800, Wei Ni wrote: >>>> Add support for hardware critical thermal limits to the >>>> SOC_THERM driver. It use the Linux thermal framework to >>>> create critical trip temp, and set it to SOC_THERM hardware. >>>> If these limits are breached, the chip will reset, and if >>>> appropriately configured, will turn off the PMIC. >>>> >>>> This support is critical for safe usage of the chip. >>>> >>>> Signed-off-by: Wei Ni >>>> --- >>>> drivers/thermal/tegra/soctherm.c | 166 +++++++++++++++++++++++++++++- >>>> drivers/thermal/tegra/soctherm.h | 7 ++ >>>> drivers/thermal/tegra/tegra124-soctherm.c | 24 +++++ >>>> drivers/thermal/tegra/tegra210-soctherm.c | 24 +++++ >>>> 4 files changed, 216 insertions(+), 5 deletions(-) >>>> >>>> diff --git a/drivers/thermal/tegra/soctherm.c b/drivers/thermal/tegra/soctherm.c >>>> index 02ac6d2e5a20..dbaab160baba 100644 >>>> --- a/drivers/thermal/tegra/soctherm.c >>>> +++ b/drivers/thermal/tegra/soctherm.c >>>> @@ -73,9 +73,14 @@ >>>> #define REG_SET_MASK(r, m, v) (((r) & ~(m)) | \ >>>> (((v) & (m >> (ffs(m) - 1))) << (ffs(m) - 1))) >>>> >>>> +static const int min_low_temp = -127000; >>>> +static const int max_high_temp = 127000; >>>> + >>>> struct tegra_thermctl_zone { >>>> void __iomem *reg; >>>> - u32 mask; >>>> + struct device *dev; >>>> + struct thermal_zone_device *tz; >>> >>> >>> Why not using tz->dev for the *dev above? >> >> The tz is thermal_zone_device, this structure doesn't have *dev. >> It only have the member "struct device device;", but this device is created for >> the thermal class, not this tegra_soctherm device. >> >>> >>>> + const struct tegra_tsensor_group *sg; >>>> }; >>>> >>>> struct tegra_soctherm { >>>> @@ -145,22 +150,158 @@ static int tegra_thermctl_get_temp(void *data, int *out_temp) >>>> u32 val; >>>> >>>> val = readl(zone->reg); >>>> - val = REG_GET_MASK(val, zone->mask); >>>> + val = REG_GET_MASK(val, zone->sg->sensor_temp_mask); >>>> *out_temp = translate_temp(val); >>>> >>>> return 0; >>>> } >>>> >>>> +static int >>>> +thermtrip_program(struct device *dev, const struct tegra_tsensor_group *sg, >>>> + int trip_temp); >>>> + >>>> +static int tegra_thermctl_set_trip_temp(void *data, int trip, int temp) >>>> +{ >>>> + struct tegra_thermctl_zone *zone = data; >>>> + struct thermal_zone_device *tz = zone->tz; >>>> + const struct tegra_tsensor_group *sg = zone->sg; >>>> + struct device *dev = zone->dev; >>>> + enum thermal_trip_type type; >>>> + int ret; >>>> + >>>> + if (!tz) >>>> + return -EINVAL; >>> >>> >>> Is the above check needed? If you saw a case in which your function is >>> called without tz, would it be the case we have a but in the probe (or >>> even worse, in thermal-core)? >> >> This tz isn't from thermal-core, it's from the "void *data". >> This *data is the private structure "struct tegra_thermctl_zone *zone = data;". >> It is registered in devm_thermal_zone_of_sensor_register(*dev, sensor_id, *data, >> *ops). And when it register successful, I will set zone->tz = z, in here, the >> zone is the private data. >> Let's consider a special case, once the thermal_zone_of_sensor_register >> successful and didn't run to "zone->tz = z" yet, then the thermal_core implement >> .set_trip(), then it may cause problems in here, although it's difficult to hit >> this case. So I think we need to do this check. > > > Can you be more specific? I don't recall a case that core would call any > driver callbacks before setting up the data structures properly. Sorry for the confusion, I mean this data structure is the private data pointer, it doesn't handled by thermal_core. Let me explain more: In this tegra soctherm driver, I run following steps in probe routine: step1: z = devm_thermal_zone_of_sensor_register(*dev, sensor_id, zone, ops); register thermal zone device, in here, the parameter "zone" is the private data pointer "structure tegra_thermctl_zone". step 2: After register, it return the "z", and I set it to the private data: zone->tz = z; In the .set_trip() callback, it will pass back this private data pointer. So if the callback was called between step1 and step2, at that time the zone->tz didn't be set yet, it will cause problems, although I didn't hit this case. This check doesn't relate with core driver, it is used to check my private data pointer. Wei. > >>> > > * Unknown Key > * 0x7DA4E256 >