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[209.132.180.67]) by mx.google.com with ESMTP id u7si5913964pgi.339.2019.05.16.13.59.50; Thu, 16 May 2019 14:00:06 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=pgPvoqyQ; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728943AbfEPRwK (ORCPT + 99 others); Thu, 16 May 2019 13:52:10 -0400 Received: from mail-it1-f196.google.com ([209.85.166.196]:54820 "EHLO mail-it1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726441AbfEPRwJ (ORCPT ); Thu, 16 May 2019 13:52:09 -0400 Received: by mail-it1-f196.google.com with SMTP id a190so7555448ite.4; Thu, 16 May 2019 10:52:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=K/rIAqoSBvW94YKGOgihZKoJ/TdYrLnwI6ascpNUFbE=; b=pgPvoqyQJhGv0tpcxJR3ZQGtqh6DeU9VS8dZdQzLk93w+5a7rihbHD3+E/D5SMSsBj AxM3QdqAv4gt+VfSCDHJd4iiymnwRt8W+FGUuIohKzcLJb7CybE/NEc2M1BlelxrqMNk ePmK5R2v83kn+NoAgYyfcY2E6sHWW1HEVoYXVPO6q/JZxd7WrFcr04wWO+oXzT4/RBff W5AJHLksSgMfcndLMmvOZtaNtnshNEYRwdtaiTTM6TU6Cg4EWwk3JVRNSpTDZGPEt8Ex n9JTe5Kr4i2wKBXHXDHcHg+Rt+EoaMBYXZW0EZjFykNAgaz5TcDmuqjWSKP0LmmDcFQA XdJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=K/rIAqoSBvW94YKGOgihZKoJ/TdYrLnwI6ascpNUFbE=; b=XDFnOpHe/A8GzhsgTiQfOe82GocpOXs41yJJys7knpp6BdrnCasCCu0syJ9MyoiQr6 b6DOcC5VWjLBfKW1MzbolsOHZ8M/xp7yBgaD1VS8PQ8sai/s6XbvtMzIW3g1vpMVu6o5 n+Qy2SG4UmjY70KFy0wWIiGJW8xad8UuQfXh8PRN5Dvpqu1RE3uFkr2aXuA7BNfFfmmO GVlb79qqhnqQwyxKvuz5OdOmuOmJ0+j66MUhmDGRl4v0O0tQseKqE767TASG+nbYXe9k psyKCydZXuR1d9wVLtEJw30GHrBnS2MYqvED4XEaTWpCkFQUhmGzDMgPnpCkXoKZG3Ac Xptg== X-Gm-Message-State: APjAAAWKslrS9n04IlwIA7br+ovOfi9V2WVwM8C62T+2ByN3ItLASm1B T0VdPZxHCdHchtAIPwcqdtXvp71vwfOyScMql7E= X-Received: by 2002:a02:a794:: with SMTP id e20mr31950271jaj.12.1558029128450; Thu, 16 May 2019 10:52:08 -0700 (PDT) MIME-Version: 1.0 References: <20190512082614.9045-1-tiny.windzz@gmail.com> <20190512082614.9045-3-tiny.windzz@gmail.com> <20190512133930.t5txssl7mou2gljt@flea> In-Reply-To: <20190512133930.t5txssl7mou2gljt@flea> From: Frank Lee Date: Fri, 17 May 2019 01:51:56 +0800 Message-ID: Subject: Re: [PATCH 2/3] thermal: sun50i: add thermal driver for h6 To: Maxime Ripard Cc: rui.zhang@intel.com, Eduardo Valentin , Daniel Lezcano , robh+dt@kernel.org, Mark Rutland , Chen-Yu Tsai , catalin.marinas@arm.com, will.deacon@arm.com, David Miller , Mauro Carvalho Chehab , Greg Kroah-Hartman , Jonathan.Cameron@huawei.com, Nicolas Ferre , paulmck@linux.ibm.com, Andy Gross , olof@lixom.net, bjorn.andersson@linaro.org, Jagan Teki , marc.w.gonzalez@free.fr, stefan.wahren@i2se.com, enric.balletbo@collabora.com, Linux PM , devicetree@vger.kernel.org, Linux ARM , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org HI Maxime, On Sun, May 12, 2019 at 9:39 PM Maxime Ripard wrote: > > Hi, > > Thanks a lot for working on this! > > On Sun, May 12, 2019 at 04:26:13AM -0400, Yangtao Li wrote: > > This patch adds the support for allwinner thermal sensor, within > > allwinner SoC. It will register sensors for thermal framework > > and use device tree to bind cooling device. > > > > Based on driver code found here: > > https://megous.com/git/linux and https://github.com/Allwinner-Homlet/H6-BSP4.9-linux > > I wouldn't place the URL in the commit log. The commit log stays > forever in the linux history. Git repos and branches are going away > over time. Removed. > > > Signed-off-by: Yangtao Li > > --- > > MAINTAINERS | 7 + > > drivers/thermal/Kconfig | 14 ++ > > drivers/thermal/Makefile | 1 + > > drivers/thermal/sun50i_thermal.c | 357 +++++++++++++++++++++++++++++++ > > The long term goal is to support all the thermal sensors, not just the > H6. Since that controller was introduced with the sun8i family, it > makes more sense to use that prefix for the driver and the functions. Done. > > > 4 files changed, 379 insertions(+) > > create mode 100644 drivers/thermal/sun50i_thermal.c > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index 3c65228e93c5..8da56582e72a 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -674,6 +674,13 @@ L: linux-crypto@vger.kernel.org > > S: Maintained > > F: drivers/crypto/sunxi-ss/ > > > > +ALLWINNER THERMAL DRIVER > > +M: Yangtao Li > > +L: linux-pm@vger.kernel.org > > +S: Maintained > > +F: Documentation/devicetree/bindings/thermal/sun50i-thermal.txt > > +F: drivers/thermal/sun50i_thermal.c > > + > > ALLWINNER VPU DRIVER > > M: Maxime Ripard > > M: Paul Kocialkowski > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > > index 653aa27a25a4..2a8d1c98c6ca 100644 > > --- a/drivers/thermal/Kconfig > > +++ b/drivers/thermal/Kconfig > > @@ -252,6 +252,20 @@ config SPEAR_THERMAL > > Enable this to plug the SPEAr thermal sensor driver into the Linux > > thermal framework. > > > > +config SUN50I_THERMAL > > + tristate "Allwinner sun50i thermal driver" > > + depends on ARCH_SUNXI || COMPILE_TEST > > + depends on HAS_IOMEM > > + depends on NVMEM > > + depends on OF > > + depends on RESET_CONTROLLER > > + help > > + Support for the sun50i thermal sensor driver into the Linux thermal > > + framework. > > + > > + To compile this driver as a module, choose M here: the > > + module will be called sun50i-thermal. > > + > > config ROCKCHIP_THERMAL > > tristate "Rockchip thermal driver" > > depends on ARCH_ROCKCHIP || COMPILE_TEST > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > > index 486d682be047..a09b30b90003 100644 > > --- a/drivers/thermal/Makefile > > +++ b/drivers/thermal/Makefile > > @@ -30,6 +30,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o > > # platform thermal drivers > > obj-y += broadcom/ > > obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o > > +obj-$(CONFIG_SUN50I_THERMAL) += sun50i_thermal.o > > obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o > > obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o > > obj-$(CONFIG_RCAR_GEN3_THERMAL) += rcar_gen3_thermal.o > > diff --git a/drivers/thermal/sun50i_thermal.c b/drivers/thermal/sun50i_thermal.c > > new file mode 100644 > > index 000000000000..3bdb3677b3d4 > > --- /dev/null > > +++ b/drivers/thermal/sun50i_thermal.c > > @@ -0,0 +1,357 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Thermal sensor driver for Allwinner SOC > > + * Copyright (C) 2019 Yangtao Li > > + * > > + * Based on the work of Icenowy Zheng > > + * Based on the work of Ondrej Jirman > > + * Based on the work of Josef Gajdusek > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +#define MAX_SENSOR_NUM 4 > > + > > +#define FT_TEMP_MASK GENMASK(11, 0) > > +#define TEMP_CALIB_MASK GENMASK(11, 0) > > +#define TEMP_TO_REG 672 > > +#define CALIBRATE_DEFAULT 0x800 > > + > > +#define SUN50I_THS_CTRL0 0x00 > > +#define SUN50I_H6_THS_ENABLE 0x04 > > +#define SUN50I_H6_THS_PC 0x08 > > +#define SUN50I_H6_THS_MFC 0x30 > > +#define SUN50I_H6_TEMP_CALIB 0xa0 > > +#define SUN50I_H6_TEMP_DATA 0xc0 > > + > > +#define SUN50I_THS_CTRL0_T_ACQ(x) ((GENMASK(15, 0) & (x)) << 16) > > +#define SUN50I_THS_FILTER_EN BIT(2) > > +#define SUN50I_THS_FILTER_TYPE(x) (GENMASK(1, 0) & (x)) > > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x) ((GENMASK(19, 0) & (x)) << 12) > > + > > +/* millidegree celsius */ > > +#define SUN50I_H6_FT_DEVIATION 7000 > > + > > +struct tsens_device; > > + > > +struct tsensor { > > + struct tsens_device *tmdev; > > + struct thermal_zone_device *tzd; > > + int id; > > +}; > > + > > +struct sun50i_thermal_chip { > > + int sensor_num; > > + int offset; > > + int scale; > > + int ft_deviation; > > + int temp_calib_base; > > + int temp_data_base; > > + int (*enable)(struct tsens_device *tmdev); > > + int (*disable)(struct tsens_device *tmdev); > > +}; > > I'm not super fond of having a lot of quirks that are not needed. If > we ever need those quirks when adding support for a new SoC, then > yeah, we should totally have some, but only when and if it's needed. > > Otherwise, the driver is more complicated for no particular reason. This is unavoidable because of the difference in soc. > > > + > > +struct tsens_device { > > IIRC the acronym used by allwinner is THS, maybe we can just use that > as a prefix? Done. > > > + const struct sun50i_thermal_chip *chip; > > + struct device *dev; > > + struct regmap *regmap; > > + struct reset_control *reset; > > + struct clk *bus_clk; > > + struct tsensor sensor[MAX_SENSOR_NUM]; > > +}; > > + > > +/* Temp Unit: millidegree Celsius */ > > +static int tsens_reg2temp(struct tsens_device *tmdev, > > + int reg) > > +{ > > + return (reg + tmdev->chip->offset) * tmdev->chip->scale; > > +} > > + > > +static int tsens_get_temp(void *data, int *temp) > > +{ > > + struct tsensor *s = data; > > + struct tsens_device *tmdev = s->tmdev; > > + int val; > > + > > + regmap_read(tmdev->regmap, tmdev->chip->temp_data_base + > > + 0x4 * s->id, &val); > > + > > + if (unlikely(val == 0)) > > + return -EBUSY; > > I'm not sure why a val equals to 0 would be associated with EBUSY? > > Also, it's not in a fast path, so you can drop the unlikely. Chances > are it's not that unlikely anyway. > BUSY: Ths have no data yet. > > + *temp = tsens_reg2temp(tmdev, val); > > + if (tmdev->chip->ft_deviation) > > + *temp += tmdev->chip->ft_deviation; > > + > > + return 0; > > +} > > + > > +static const struct thermal_zone_of_device_ops tsens_ops = { > > + .get_temp = tsens_get_temp, > > +}; > > + > > +static const struct regmap_config config = { > > + .reg_bits = 32, > > + .val_bits = 32, > > + .reg_stride = 4, > > + .fast_io = true, > > +}; > > + > > +static int tsens_init(struct tsens_device *tmdev) > > +{ > > + struct device *dev = tmdev->dev; > > + struct platform_device *pdev = to_platform_device(dev); > > + struct resource *mem; > > + void __iomem *base; > > + > > + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > + base = devm_ioremap_resource(dev, mem); > > + if (IS_ERR(base)) > > + return PTR_ERR(base); > > + > > + tmdev->regmap = devm_regmap_init_mmio_clk(dev, "bus", > > + base, > > + &config); > > + if (IS_ERR(tmdev->regmap)) > > + return PTR_ERR(tmdev->regmap); > > + > > + tmdev->reset = devm_reset_control_get(dev, "bus"); > > + if (IS_ERR(tmdev->reset)) > > + return PTR_ERR(tmdev->reset); > > + > > + tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus"); > > + if (IS_ERR(tmdev->bus_clk)) > > + return PTR_ERR(tmdev->bus_clk); > > You don't need to get that clock if regmap has it already. It seems that clk init should be after reset reset_control_deassert. So I convert devm_regmap_init_mmio_clk to devm_regmap_init_mmio. > > > + return 0; > > +} > > + > > +/* > > + * Even if the external calibration data stored in sid is not accessible, > > + * the THS hardware can still work, although the data won't be so accurate. > > + * The default value of calibration register is 0x800 for every sensor, > > + * and the calibration value is usually 0x7xx or 0x8xx, so they won't be > > + * away from the default value for a lot. > > + * > > + * So here we do not return error if the calibartion data is > > + * not available, except the probe needs deferring. > > + */ > > +static int tsens_calibrate(struct tsens_device *tmdev) > > +{ > > + struct nvmem_cell *calcell; > > + struct device *dev = tmdev->dev; > > + u16 *caldata; > > + size_t callen; > > + int ft_temp; > > + int i = 0; > > + > > + calcell = devm_nvmem_cell_get(dev, "calib"); > > + if (IS_ERR(calcell)) { > > + if (PTR_ERR(calcell) == -EPROBE_DEFER) > > + return -EPROBE_DEFER; > > + > > + goto out; > > + } > > + > > + caldata = nvmem_cell_read(calcell, &callen); > > + if (IS_ERR(caldata)) > > + goto out; > > + > > + if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) > > + goto out_free; > > The first part of your or isn't obvious and should have a comment. > > The second part shouldn't return 0 but an error Done. > > > + > > + /* > > + * The calbration data on H6 is stored as temperature-value > > + * pair when being filled at factory test stage. > > + * The unit of stored FT temperature is 0.1 degreee celusis. > > + */ > > + ft_temp = caldata[0] & FT_TEMP_MASK; > > + > > + for (; i < tmdev->chip->sensor_num; i++) { > > Usually you would initialize i here, and not when declared. Done. > > > + int reg = (int)caldata[i + 1]; > > + int sensor_temp = tsens_reg2temp(tmdev, reg); > > + int delta, cdata, calib_offest; > > + > > + /* > > + * To calculate the calibration value: > > + * > > + * X(in Celsius) = Ts - ft_temp > > + * delta = X * 10000 / TEMP_TO_REG > > + * cdata = CALIBRATE_DEFAULT - delta > > + * > > + * cdata: calibration value > > + */ > > + delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG; > > + cdata = CALIBRATE_DEFAULT - delta; > > + if (cdata & ~TEMP_CALIB_MASK) { > > + dev_warn(dev, "sensor%d calibration value error", i); > > + > > + continue; > > + } > > + > > + calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4; > > + > > + if (i % 2) { > > + int val; > > + > > + regmap_read(tmdev->regmap, calib_offest, &val); > > + val = (val & TEMP_CALIB_MASK) | (cdata << 16); > > + regmap_write(tmdev->regmap, calib_offest, val); > > + } else > > + regmap_write(tmdev->regmap, calib_offest, cdata); > > This should have brackets as well Done. > > > + } > > + > > +out_free: > > + kfree(caldata); > > +out: > > + return 0; > > +} > > + > > +static int tsens_register(struct tsens_device *tmdev) > > +{ > > + struct thermal_zone_device *tzd; > > + int i = 0; > > + > > + for (; i < tmdev->chip->sensor_num; i++) { > > Ditto Done. > > > + tmdev->sensor[i].tmdev = tmdev; > > + tmdev->sensor[i].id = i; > > + tmdev->sensor[i].tzd = devm_thermal_zone_of_sensor_register( > > + tmdev->dev, i, &tmdev->sensor[i], > > + &tsens_ops); > > + if (IS_ERR(tmdev->sensor[i].tzd)) > > + return PTR_ERR(tzd); > > + } > > + > > + return 0; > > +} > > + > > +static int tsens_probe(struct platform_device *pdev) > > +{ > > + struct tsens_device *tmdev; > > + struct device *dev = &pdev->dev; > > + int ret; > > + > > + tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL); > > + if (!tmdev) > > + return -ENOMEM; > > + > > + tmdev->dev = dev; > > + tmdev->chip = of_device_get_match_data(&pdev->dev); > > + if (!tmdev->chip) > > + return -EINVAL; > > + > > + ret = tsens_init(tmdev); > > + if (ret) > > + return ret; > > + > > + ret = tsens_register(tmdev); > > + if (ret) > > + return ret; > > + > > + ret = tmdev->chip->enable(tmdev); > > + if (ret) > > + return ret; > > > > + platform_set_drvdata(pdev, tmdev); > > Your registration should be the very last thing you do. Otherwise, you > have a small window where the get_temp callback can be called, but the > driver will not be functional yet. No. Anyway, ths data qcquisition is ms level. > > > + return ret; > > +} > > + > > +static int tsens_remove(struct platform_device *pdev) > > +{ > > + struct tsens_device *tmdev = platform_get_drvdata(pdev); > > + > > + tmdev->chip->disable(tmdev); > > + > > + return 0; > > +} > > + > > +static int sun50i_thermal_enable(struct tsens_device *tmdev) > > +{ > > + int ret, val; > > + > > + ret = reset_control_deassert(tmdev->reset); > > + if (ret) > > + return ret; > > + > > + ret = clk_prepare_enable(tmdev->bus_clk); > > + if (ret) > > + goto assert_reset; > > This is done by regmap as well > > > + ret = tsens_calibrate(tmdev); > > + if (ret) > > + return ret; > > + > > + /* > > + * clkin = 24MHz > > + * T acquire = clkin / (SUN50I_THS_CTRL0_T_ACQ + 1) > > + * = 20us > > + */ > > + regmap_write(tmdev->regmap, SUN50I_THS_CTRL0, > > + SUN50I_THS_CTRL0_T_ACQ(479)); > > + /* average over 4 samples */ > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC, > > + SUN50I_THS_FILTER_EN | > > + SUN50I_THS_FILTER_TYPE(1)); > > + /* period = (SUN50I_H6_THS_PC_TEMP_PERIOD + 1) * 4096 / clkin; ~10ms */ > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_PC, > > + SUN50I_H6_THS_PC_TEMP_PERIOD(58)); > > + /* enable sensor */ > > + val = GENMASK(tmdev->chip->sensor_num - 1, 0); > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val); > > + > > + return 0; > > + > > +assert_reset: > > + reset_control_assert(tmdev->reset); > > + > > + return ret; > > Can't we do that with runtime_pm? > Saving energy doesn't make much sense compared to system security. thx, Yangtao > Thanks! > Maxime > > -- > Maxime Ripard, Bootlin > Embedded Linux and Kernel engineering > https://bootlin.com