Re: [PATCH v2 2/2] hwmon: (sfctemp) Add StarFive JH7100 temperature sensor
From: Guenter Roeck <linux@roeck-us.net>
Date: 2021-06-28 15:44:14
Also in:
linux-doc, linux-hwmon, lkml
On Thu, Jun 24, 2021 at 06:21:08PM +0200, Emil Renner Berthing wrote:
quoted hunk ↗ jump to hunk
From: Emil Renner Berthing <kernel@esmil.dk> Register definitions and conversion constants based on sfctemp driver by Samin in the StarFive 5.10 kernel. Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> Signed-off-by: Samin Guo <redacted> --- Documentation/hwmon/index.rst | 1 + Documentation/hwmon/sfctemp.rst | 32 ++++ MAINTAINERS | 8 + drivers/hwmon/Kconfig | 10 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/sfctemp.c | 288 ++++++++++++++++++++++++++++++++ 6 files changed, 340 insertions(+) create mode 100644 Documentation/hwmon/sfctemp.rst create mode 100644 drivers/hwmon/sfctemp.cdiff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 9ed60fa84cbe..f23308e97d2e 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst@@ -161,6 +161,7 @@ Hardware Monitoring Kernel Drivers sch5627 sch5636 scpi-hwmon + sfctemp sht15 sht21 sht3xdiff --git a/Documentation/hwmon/sfctemp.rst b/Documentation/hwmon/sfctemp.rst new file mode 100644 index 000000000000..465edce2fea5 --- /dev/null +++ b/Documentation/hwmon/sfctemp.rst@@ -0,0 +1,32 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Kernel driver sfctemp +===================== + +Supported chips: + - StarFive JH7100 + +Authors: + - Emil Renner Berthing <kernel@esmil.dk> + +Description +----------- + +This driver adds support for reading the built-in temperature sensor on the +JH7100 RISC-V SoC by StarFive Technology Co. Ltd. + +``sysfs`` interface +------------------- + +The temperature sensor can be enabled, disabled and queried via the standard +hwmon interface in sysfs under ``/sys/class/hwmon/hwmonX`` for some value of +``X``: + +================ ==== ============================================= +Name Perm Description +================ ==== ============================================= +temp1_enable RW Enable or disable temperature sensor. + Automatically enabled by the driver, + but may be disabled to save power. +temp1_input RO Temperature reading in milli-degrees Celsius. +================ ==== =============================================diff --git a/MAINTAINERS b/MAINTAINERS index 8c5ee008301a..a7d25a672270 100644 --- a/MAINTAINERS +++ b/MAINTAINERS@@ -16535,6 +16535,14 @@ L: netdev@vger.kernel.org S: Supported F: drivers/net/ethernet/sfc/ +SFCTEMP HWMON DRIVER +M: Emil Renner Berthing <kernel@esmil.dk> +L: linux-hwmon@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/hwmon/starfive,jh7100-temp.yaml +F: Documentation/hwmon/sfctemp.rst +F: drivers/hwmon/sfctemp.c + SFF/SFP/SFP+ MODULE SUPPORT M: Russell King <linux@armlinux.org.uk> L: netdev@vger.kernel.orgdiff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 87624902ea80..7da8fd8beb06 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig@@ -1751,6 +1751,16 @@ 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" + depends on OF && (RISCV || COMPILE_TEST) + 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 I2Cdiff --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.odiff --git a/drivers/hwmon/sfctemp.c b/drivers/hwmon/sfctemp.c new file mode 100644 index 000000000000..4328aacf9272 --- /dev/null +++ b/drivers/hwmon/sfctemp.c@@ -0,0 +1,288 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 Emil Renner Berthing <kernel@esmil.dk> + * Copyright (C) 2021 Samin Guo <samin.guo@starfivetech.com> + */ +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/hwmon.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +/* + * TempSensor reset. The RSTN can be de-asserted once the analog core has + * powered up. Trst(min 100ns) + * 0:reset 1:de-assert + */ +#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 conversion value output. + * Temp(C)=DOUT*Y/4094 - K + */ +#define SFCTEMP_DOUT_POS 16 +#define SFCTEMP_DOUT_MSK GENMASK(27, 16) + +/* DOUT to Celcius conversion constants */ +#define SFCTEMP_Y1000 237500L +#define SFCTEMP_Z 4094L +#define SFCTEMP_K1000 81100L + +struct sfctemp { + /* serialize access to hardware register and enabled below */ + 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 void sfctemp_disable_action(void *data) +{ + sfctemp_disable(data); +} + +static int sfctemp_convert(struct sfctemp *sfctemp, long *val) +{ + int ret; + + 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;
Does this need to handle timeouts ? if (ret == 0) return -ETIMEDOUT;
+
+ /* 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;
+ 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 = devm_add_action(dev, sfctemp_disable_action, sfctemp);
+ if (ret)
+ return ret;
+
+ ret = sfctemp_enable(sfctemp);
+ if (ret)
+ return ret;
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev, pdev->name, sfctemp,
+ &sfctemp_chip_info, NULL);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+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,
+};
+module_platform_driver(sfctemp_driver);
+
+MODULE_AUTHOR("Emil Renner Berthing");
+MODULE_DESCRIPTION("StarFive JH7100 temperature sensor driver");
+MODULE_LICENSE("GPL");
--
2.32.0