Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753633AbdGUNVX (ORCPT ); Fri, 21 Jul 2017 09:21:23 -0400 Received: from conssluserg-05.nifty.com ([210.131.2.90]:42647 "EHLO conssluserg-05.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750777AbdGUNVU (ORCPT ); Fri, 21 Jul 2017 09:21:20 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-05.nifty.com v6LDL7dO028423 X-Nifty-SrcIP: [209.85.161.182] MIME-Version: 1.0 In-Reply-To: <1500636105-11520-3-git-send-email-hayashi.kunihiko@socionext.com> References: <1500636105-11520-1-git-send-email-hayashi.kunihiko@socionext.com> <1500636105-11520-3-git-send-email-hayashi.kunihiko@socionext.com> From: Masahiro Yamada Date: Fri, 21 Jul 2017 22:21:05 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v5 2/2] thermal: uniphier: add UniPhier thermal driver To: Kunihiko Hayashi Cc: rui.zhang@intel.com, Eduardo Valentin , linux-pm@vger.kernel.org, linux-arm-kernel , Linux Kernel Mailing List , Rob Herring , Mark Rutland , Masami Hiramatsu , Jassi Brar Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5861 Lines: 175 2017-07-21 20:21 GMT+09:00 Kunihiko Hayashi : > +static int uniphier_tm_initialize_sensor(struct uniphier_tm_dev *tdev) > +{ > + struct regmap *map = tdev->regmap; > + u32 val; > + int ret; > + > + /* stop PVT */ > + regmap_write_bits(map, tdev->data->block_base + PVTCTLEN, > + PVTCTLEN_EN, 0); > + > + /* > + * set default value if missing calibrated value > + * > + * Since SoC has a calibrated value that was set in advance, > + * TMODCOEF shows non-zero and PVT refers the value internally. > + * > + * However, some boards don't have the calibrated value. > + * In that case, TMODCOEF shows zero and the driver has to set > + * default value manually. > + */ > + ret = regmap_read(map, tdev->data->map_base + TMODCOEF, &val); > + if (ret) > + return ret; > + if (!val) > + regmap_write(map, tdev->data->tmod_setup_addr, > + TMODSETUP0_EN | TMODSETUP0_VAL(tdev->tmod_calib0) | > + TMODSETUP1_EN | TMODSETUP1_VAL(tdev->tmod_calib1)); This code is strange. What if TMODCOEF has no calibrated value and "socionext,tmod-calibration" is not set either? ->tmod_setupaddr will be set to zero and the sensor would not work, right? > + /* get tmod-calibration values */ > + calib = of_get_property(dev->of_node, "socionext,tmod-calibration", > + NULL); > + if (calib) { > + tdev->tmod_calib0 = of_read_number(calib, 1); > + tdev->tmod_calib1 = of_read_number(calib + 1, 1); > + } >From your DT change (https://patchwork.kernel.org/patch/9826391/), this property seems a pair of u32 values, like follows: socionext,tmod-calibration = <0x0f22 0x68ee>; Why do you need to use of_read_number() to retrieve each u32 value? See the comment and return value (u64): ------------------>8----------------- /* Helper to read a big number; size is in cells (not bytes) */ static inline u64 of_read_number(const __be32 *cell, int size) ------------------8<----------------- Also, you are not checking the length of the property. of_read_number() may over-run the property. of_property_read_u32_array() will be a better choice. I'd propose the code like follows: diff --git a/drivers/thermal/uniphier_thermal.c b/drivers/thermal/uniphier_thermal.c index 1a77c5bf6930..eea8a3053584 100644 --- a/drivers/thermal/uniphier_thermal.c +++ b/drivers/thermal/uniphier_thermal.c @@ -94,16 +94,16 @@ struct uniphier_tm_soc_data { struct uniphier_tm_dev { struct regmap *regmap; bool alert_en[ALERT_CH_NUM]; - u32 tmod_calib0; - u32 tmod_calib1; struct thermal_zone_device *tz_dev; const struct uniphier_tm_soc_data *data; }; -static int uniphier_tm_initialize_sensor(struct uniphier_tm_dev *tdev) +static int uniphier_tm_initialize_sensor(struct uniphier_tm_dev *tdev, + struct device *dev) { struct regmap *map = tdev->regmap; u32 val; + u32 tmod_val[2]; int ret; /* stop PVT */ @@ -123,10 +123,22 @@ static int uniphier_tm_initialize_sensor(struct uniphier_tm_dev *tdev) ret = regmap_read(map, tdev->data->map_base + TMODCOEF, &val); if (ret) return ret; - if (!val) + if (!val) { + /* + * No preset value found in the register. + * Look for the fall-back values in DT. + */ + ret = of_property_read_u32_array(dev->of_node, + "socionext,tmod-calibration", + tmod_val, ARRAY_SIZE(tmod_val)); + if (ret) { + dev_err(dev, "neither register nor DT has calibrated values.\n"); + return ret; + } regmap_write(map, tdev->data->tmod_setup_addr, - TMODSETUP0_EN | TMODSETUP0_VAL(tdev->tmod_calib0) | - TMODSETUP1_EN | TMODSETUP1_VAL(tdev->tmod_calib1)); + TMODSETUP0_EN | TMODSETUP0_VAL(tmod_val[0]) | + TMODSETUP1_EN | TMODSETUP1_VAL(tmod_val[1])); + } /* select temperature mode */ regmap_write_bits(map, tdev->data->block_base + PVTCTLMODE, @@ -254,7 +266,6 @@ static int uniphier_tm_probe(struct platform_device *pdev) struct device_node *parent; struct uniphier_tm_dev *tdev; const struct thermal_trip *trips; - const __be32 *calib; int i, ret, irq, ntrips, crit_temp = INT_MAX; tdev = devm_kzalloc(dev, sizeof(*tdev), GFP_KERNEL); @@ -269,14 +280,6 @@ static int uniphier_tm_probe(struct platform_device *pdev) if (irq < 0) return irq; - /* get tmod-calibration values */ - calib = of_get_property(dev->of_node, "socionext,tmod-calibration", - NULL); - if (calib) { - tdev->tmod_calib0 = of_read_number(calib, 1); - tdev->tmod_calib1 = of_read_number(calib + 1, 1); - } - /* get regmap from syscon node */ parent = of_get_parent(dev->of_node); /* parent should be syscon node */ regmap = syscon_node_to_regmap(parent); @@ -288,7 +291,7 @@ static int uniphier_tm_probe(struct platform_device *pdev) } tdev->regmap = regmap; - ret = uniphier_tm_initialize_sensor(tdev); + ret = uniphier_tm_initialize_sensor(tdev, dev); if (ret) { dev_err(dev, "failed to initialize sensor\n"); return ret; -- Best Regards Masahiro Yamada