From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2987FC49361 for ; Thu, 17 Jun 2021 15:36:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 085D1613E2 for ; Thu, 17 Jun 2021 15:36:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232541AbhFQPic convert rfc822-to-8bit (ORCPT ); Thu, 17 Jun 2021 11:38:32 -0400 Received: from mail-yb1-f169.google.com ([209.85.219.169]:46642 "EHLO mail-yb1-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231661AbhFQPib (ORCPT ); Thu, 17 Jun 2021 11:38:31 -0400 Received: by mail-yb1-f169.google.com with SMTP id h15so8790878ybm.13; Thu, 17 Jun 2021 08:36:23 -0700 (PDT) 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:content-transfer-encoding; bh=bdQuWeQt6RjtSg4ZgCNzfCdi542ckNbGHKSYlXEGyqc=; b=CmbZl1Amn6alLwaP39jIztg2dD9wT5HYaMH0vmRGifBh4O9nlTVntZ/dRdTsXIHCy5 aTh2DRVNXfiWAqANtD/pUERXjkAtIdW1dGoHl49GRR5vG2itgJNC1weZctaLxKzhKh/x H3oHthJ94nO9WtDnJyduIpOvaS3S+XsAHZEBK96FH/vMfire943t0vEXNU3PewttYvWN eOUf2T5OiCAvROVOw/+IyOw+FZgjMux7RBZw5FHDLyCEACzztoaxEvbvBNIA6rRzDbaU BRblfCX+ibq4xPvyvcW69lLhwifffygdpTYKyOQgexWCCMms3ih56dlQi7wbbuB7Zs8K +1Vw== X-Gm-Message-State: AOAM532x2SksKqr62l8MSLO6wY/n52uNJfLjksCrkhhZs4q/iX+GBNOi TbJP9BsPmXiGgAa+AgXNyozdfUdcKybWT3hytqY= X-Google-Smtp-Source: ABdhPJxoPYfA3myfATBHrxyD3e4u4v3B9+ji5LUHFHCGi4wP9+vD9SA5XsaTpiL8O+ftIHM/TIJOdgJDp988HdsjugA= X-Received: by 2002:a25:3d41:: with SMTP id k62mr6597424yba.479.1623944183284; Thu, 17 Jun 2021 08:36:23 -0700 (PDT) MIME-Version: 1.0 References: <20210616181545.496149-1-kernel@esmil.dk> <20210616181545.496149-3-kernel@esmil.dk> <20210617150740.GA2676642@roeck-us.net> In-Reply-To: <20210617150740.GA2676642@roeck-us.net> From: Emil Renner Berthing Date: Thu, 17 Jun 2021 17:36:12 +0200 Message-ID: Subject: Re: [PATCH v1 2/2] hwmon: (sfctemp) Add StarFive JH7100 temperature sensor To: Guenter Roeck Cc: Jean Delvare , Rob Herring , Samin Guo , linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 17 Jun 2021 at 17:07, Guenter Roeck wrote: > On Wed, Jun 16, 2021 at 08:15:45PM +0200, Emil Renner Berthing wrote: > > Register definitions based on sfctemp driver in the StarFive > > 5.10 kernel by Samin Guo . > > > > Signed-off-by: Emil Renner Berthing > > --- > > > > @Samin: Only the register definitions and conversion constants are left > > from your driver, but still it would be really nice if you could reply > > to this mail with your Signed-off-by. Thanks! > > > > > > drivers/hwmon/Kconfig | 9 ++ > > drivers/hwmon/Makefile | 1 + > > drivers/hwmon/sfctemp.c | 309 ++++++++++++++++++++++++++++++++++++++++ > > Documentation/hwmon/sfctemp is missing. > > > 3 files changed, 319 insertions(+) > > create mode 100644 drivers/hwmon/sfctemp.c > > > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > > index 87624902ea80..fa7562920dfa 100644 > > --- a/drivers/hwmon/Kconfig > > +++ b/drivers/hwmon/Kconfig > > @@ -1751,6 +1751,15 @@ config SENSORS_STTS751 > > This driver can also be built as a module. If so, the module > > will be called stts751. > > > > +config SENSORS_SFCTEMP > > + tristate "Starfive JH7100 temperature sensor" > > + help > > + If you say yes here you get support for temperature sensor > > + on the Starfive JH7100 SoC. > > + > > + This driver can also be built as a module. If so, the module > > + will be called sfctemp. > > + > > config SENSORS_SMM665 > > tristate "Summit Microelectronics SMM665" > > depends on I2C > > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > > index 59e78bc212cf..3723eb580bf3 100644 > > --- a/drivers/hwmon/Makefile > > +++ b/drivers/hwmon/Makefile > > @@ -167,6 +167,7 @@ obj-$(CONFIG_SENSORS_SBTSI) += sbtsi_temp.o > > obj-$(CONFIG_SENSORS_SCH56XX_COMMON)+= sch56xx-common.o > > obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o > > obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o > > +obj-$(CONFIG_SENSORS_SFCTEMP) += sfctemp.o > > obj-$(CONFIG_SENSORS_SL28CPLD) += sl28cpld-hwmon.o > > obj-$(CONFIG_SENSORS_SHT15) += sht15.o > > obj-$(CONFIG_SENSORS_SHT21) += sht21.o > > diff --git a/drivers/hwmon/sfctemp.c b/drivers/hwmon/sfctemp.c > > new file mode 100644 > > index 000000000000..62a838063e4e > > --- /dev/null > > +++ b/drivers/hwmon/sfctemp.c > > @@ -0,0 +1,309 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Copyright (C) 2021 Emil Renner Berthing > > + * Copyright (C) 2021 Samin Guo > > + */ > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > This may work on some systems, but on others it will result in: > > drivers/hwmon/sfctemp.c: In function ‘sfctemp_power_up’: > drivers/hwmon/sfctemp.c:76:2: error: implicit declaration of function ‘writel’ > > drivers/hwmon/sfctemp.c: In function ‘sfctemp_convert’: > drivers/hwmon/sfctemp.c:144:17: error: implicit declaration of function ‘readl’ > > It is necessary to include . > > > + > > +/* TempSensor reset. The RSTN can be de-asserted once the analog core has > > + * powered up. Trst(min 100ns) > > + * 0:reset 1:de-assert */ > > /* > * Please use standard multi-line comments. > * checkpatch would tell you, plus it has other complaints. > * Please run checkpatch --strict and fix what it reports. > */ > > +#define SFCTEMP_RSTN BIT(0) > > + > > +/* TempSensor analog core power down. The analog core will be powered up > > + * Tpu(min 50us) after PD is de-asserted. RSTN should be held low until the > > + * analog core is powered up. > > + * 0:power up 1:power down */ > > +#define SFCTEMP_PD BIT(1) > > + > > +/* TempSensor start conversion enable. > > + * 0:disable 1:enable */ > > +#define SFCTEMP_RUN BIT(2) > > + > > +/* TempSensor calibration mode enable. > > + * 0:disable 1:enable */ > > +#define SFCTEMP_CAL BIT(4) > > + > > +/* TempSensor signature enable. Generate a toggle value outputting on DOUT for > > + * test purpose. > > + * 0:disable 1:enable */ > > +#define SFCTEMP_SGN BIT(5) > > + > > +/* TempSensor test access control. > > + * 0000:normal 0001:Test1 0010:Test2 0011:Test3 > > + * 0100:Test4 1000:Test8 1001:Test9 */ > > +#define SFCTEMP_TM_Pos 12 > > +#define SFCTEMP_TM_Msk GENMASK(15, 12) > > Defines should upper case. Besides, the above defines are not > used. Please remove unused defines, and please rename the others > to be upper case only. > > > + > > +/* TempSensor conversion value output. > > + * Temp(c)=DOUT*Y/4094 - K */ > > +#define SFCTEMP_DOUT_Pos 16 > > +#define SFCTEMP_DOUT_Msk GENMASK(27, 16) > > + > > +/* TempSensor digital test output. */ > > +#define SFCTEMP_DIGO BIT(31) > > + > > +/* DOUT to Celcius conversion constants */ > > +#define SFCTEMP_Y1000 237500L > > +#define SFCTEMP_Z 4094L > > Please use > > #define, eg > > #define SFCTEMP_Y1000 237500L > #define SFCTEMP_Z 4094L > > for all defines. > > > +#define SFCTEMP_K1000 81100L > > + > > +struct sfctemp { > > + struct mutex lock; > > + struct completion conversion_done; > > + void __iomem *regs; > > + bool enabled; > > +}; > > + > > +static irqreturn_t sfctemp_isr(int irq, void *data) > > +{ > > + struct sfctemp *sfctemp = data; > > + > > + complete(&sfctemp->conversion_done); > > + return IRQ_HANDLED; > > +} > > + > > +static void sfctemp_power_up(struct sfctemp *sfctemp) > > +{ > > + /* make sure we're powered down first */ > > + writel(SFCTEMP_PD, sfctemp->regs); > > + udelay(1); > > + > > + writel(0, sfctemp->regs); > > + /* wait t_pu(50us) + t_rst(100ns) */ > > + usleep_range(60, 200); > > + > > + /* de-assert reset */ > > + writel(SFCTEMP_RSTN, sfctemp->regs); > > + udelay(1); /* wait t_su(500ps) */ > > +} > > + > > +static void sfctemp_power_down(struct sfctemp *sfctemp) > > +{ > > + writel(SFCTEMP_PD, sfctemp->regs); > > +} > > + > > +static void sfctemp_run_single(struct sfctemp *sfctemp) > > +{ > > + writel(SFCTEMP_RSTN | SFCTEMP_RUN, sfctemp->regs); > > + udelay(1); > > + writel(SFCTEMP_RSTN, sfctemp->regs); > > +} > > + > > +static int sfctemp_enable(struct sfctemp *sfctemp) > > +{ > > + mutex_lock(&sfctemp->lock); > > + if (sfctemp->enabled) > > + goto done; > > + > > + sfctemp_power_up(sfctemp); > > + sfctemp->enabled = true; > > +done: > > + mutex_unlock(&sfctemp->lock); > > + return 0; > > +} > > + > > +static int sfctemp_disable(struct sfctemp *sfctemp) > > +{ > > + mutex_lock(&sfctemp->lock); > > + if (!sfctemp->enabled) > > + goto done; > > + > > + sfctemp_power_down(sfctemp); > > + sfctemp->enabled = false; > > +done: > > + mutex_unlock(&sfctemp->lock); > > + return 0; > > +} > > + > > +static int sfctemp_convert(struct sfctemp *sfctemp, long *val) > > +{ > > + long ret; > > Why long ? Sure, wait_for_completion_interruptible_timeout() > returns a long, but it will never return a value large enough to warrant > a long here. > > > + > > + mutex_lock(&sfctemp->lock); > > + if (!sfctemp->enabled) { > > + ret = -ENODATA; > > + goto out; > > + } > > + > > + sfctemp_run_single(sfctemp); > > + > > + ret = wait_for_completion_interruptible_timeout(&sfctemp->conversion_done, > > + msecs_to_jiffies(10)); > > + if (ret < 0) > > + goto out; > > + > > + /* calculate temperature in milli Celcius */ > > + *val = (long)((readl(sfctemp->regs) & SFCTEMP_DOUT_Msk) >> SFCTEMP_DOUT_Pos) > > + * SFCTEMP_Y1000 / SFCTEMP_Z - SFCTEMP_K1000; > > + > > + ret = 0; > > +out: > > + mutex_unlock(&sfctemp->lock); > > + return ret; > > +} > > + > > +static umode_t sfctemp_is_visible(const void *data, enum hwmon_sensor_types type, > > + u32 attr, int channel) > > +{ > > + switch (type) { > > + case hwmon_temp: > > + switch (attr) { > > + case hwmon_temp_enable: > > + return 0644; > > + case hwmon_temp_input: > > + return 0444; > > + } > > + return 0; > > + default: > > + return 0; > > + } > > +} > > + > > +static int sfctemp_read(struct device *dev, enum hwmon_sensor_types type, > > + u32 attr, int channel, long *val) > > +{ > > + struct sfctemp *sfctemp = dev_get_drvdata(dev); > > + > > + switch (type) { > > + case hwmon_temp: > > + switch (attr) { > > + case hwmon_temp_enable: > > + *val = sfctemp->enabled; > > + return 0; > > + case hwmon_temp_input: > > + return sfctemp_convert(sfctemp, val); > > + } > > + return -EINVAL; > > + default: > > + return -EINVAL; > > + } > > +} > > + > > +static int sfctemp_write(struct device *dev, enum hwmon_sensor_types type, > > + u32 attr, int channel, long val) > > +{ > > + struct sfctemp *sfctemp = dev_get_drvdata(dev); > > + > > + switch (type) { > > + case hwmon_temp: > > + switch (attr) { > > + case hwmon_temp_enable: > > + if (val == 0) > > + return sfctemp_disable(sfctemp); > > + if (val == 1) > > + return sfctemp_enable(sfctemp); > > + break; > > + } > > + return -EINVAL; > > + default: > > + return -EINVAL; > > + } > > +} > > + > > +static const struct hwmon_channel_info *sfctemp_info[] = { > > + HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ), > > + HWMON_CHANNEL_INFO(temp, HWMON_T_ENABLE | HWMON_T_INPUT), > > + NULL > > +}; > > + > > +static const struct hwmon_ops sfctemp_hwmon_ops = { > > + .is_visible = sfctemp_is_visible, > > + .read = sfctemp_read, > > + .write = sfctemp_write, > > +}; > > + > > +static const struct hwmon_chip_info sfctemp_chip_info = { > > + .ops = &sfctemp_hwmon_ops, > > + .info = sfctemp_info, > > +}; > > + > > +static int sfctemp_probe(struct platform_device *pdev) > > +{ > > + struct device *dev = &pdev->dev; > > + struct device *hwmon_dev; > > + struct resource *mem; > > + struct sfctemp *sfctemp; > > + long val; > > + int ret; > > + > > + sfctemp = devm_kzalloc(dev, sizeof(*sfctemp), GFP_KERNEL); > > + if (!sfctemp) > > + return -ENOMEM; > > + > > + dev_set_drvdata(dev, sfctemp); > > + mutex_init(&sfctemp->lock); > > + init_completion(&sfctemp->conversion_done); > > + > > + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > + sfctemp->regs = devm_ioremap_resource(dev, mem); > > + if (IS_ERR(sfctemp->regs)) > > + return PTR_ERR(sfctemp->regs); > > + > > + ret = platform_get_irq(pdev, 0); > > + if (ret < 0) > > + return ret; > > + > > + ret = devm_request_irq(dev, ret, sfctemp_isr, > > + IRQF_SHARED, pdev->name, sfctemp); > > + if (ret) { > > + dev_err(dev, "request irq failed: %d\n", ret); > > + return ret; > > + } > > + > > + ret = sfctemp_enable(sfctemp); > > + if (ret) > > + return ret; > > Please consider adding devm_add_action_or_reset() to disable the sensor. > Then you can use devm_hwmon_device_register_with_info(), and there is > no need for a remove function. > > + > > + hwmon_dev = hwmon_device_register_with_info(dev, pdev->name, sfctemp, > > + &sfctemp_chip_info, NULL); > > + if (IS_ERR(hwmon_dev)) > > + return PTR_ERR(hwmon_dev); > > + > > + /* do a conversion to check everything works */ > > + ret = sfctemp_convert(sfctemp, &val); > > Please drop this check; it will result in substantial boot delays. > The assumption is the the hardware works; the system should not be > optimized (slowed down) to handle a potential and hopefully rare > failure case. > > > + if (ret) { > > + hwmon_device_unregister(hwmon_dev); > > + return ret; > > + } > > + > > + dev_info(dev, "%ld.%03ld C\n", val / 1000, val % 1000); > > Please drop this message. Anyone interested in boot-time temperature > readings can add a script and get it from sysfs attributes as needed. > > > + return 0; > > +} > > + > > +static int sfctemp_remove(struct platform_device *pdev) > > +{ > > + struct device *dev = &pdev->dev; > > + struct sfctemp *sfctemp = dev_get_drvdata(dev); > > + > > + hwmon_device_unregister(dev); > > + return sfctemp_disable(sfctemp); > > +} > > + > > +static const struct of_device_id sfctemp_of_match[] = { > > + { .compatible = "starfive,jh7100-temp" }, > > + { /* sentinel */ } > > +}; > > + > > +MODULE_DEVICE_TABLE(of, sfctemp_of_match); > > + > > +static struct platform_driver sfctemp_driver = { > > + .driver = { > > + .name = "sfctemp", > > + .of_match_table = of_match_ptr(sfctemp_of_match), > > + }, > > + .probe = sfctemp_probe, > > + .remove = sfctemp_remove, > > +}; > > +module_platform_driver(sfctemp_driver); > > + > > +MODULE_AUTHOR("Emil Renner Berthing"); > > +MODULE_DESCRIPTION("StarFive JH7100 temperature sensor driver"); > > +MODULE_LICENSE("GPL"); Hi Guenter, Thanks for the review. It all sounds reasonable. I'll address it all in v2. /Emil