The Gateworks System Controller has a hwmon sub-component that exposes up to 16 ADC's, some of which are temperature sensors, others which are voltage inputs. The ADC configuration (register mapping and name) is configured via device-tree and varies board to board. Signed-off-by: Tim Harvey <tharvey@xxxxxxxxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- v11: - no change v10: - no change v9: - use exported gsc_{read,write} - added Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> v8: - move regmap init to hwmon v7: - fix whitespace in Kconfig - remove unnecessary device pointer in private data - change divider from mili-ohms to ohms - move fan base property to reg v6: - fix size of info field - improve pwm output control documentation - include unit suffix in divider and offset - change subnode name to gsc-adc - change to fan subnode - fix voltage offset v5: - fix various checkpatch issues - correct gsc-hwmon.rst in MAINTAINERS - encorporate Gunter's feedback: - switch to SENSOR_DEVICE_ATTR_{RW,RO} - use tmp value to avoid excessive pointer deference - simplify shift operation - scale voffset once - simplify is_visible function - remove empty line at end of file v4: - adjust for uV offset from device-tree - remove unnecessary optional write function - remove register range check - change dev_err prints to use gsc dev - hard-code resolution/scaling for raw adcs - describe units of ADC resolution - move to using pwm<n>_auto_point<m>_{pwm,temp} for FAN PWM - ensure space before/after operators - remove unnecessary parens - remove more debugging - add default case and comment for type_voltage - remove unnecessary index bounds checks for channel - remove unnecessary clearing of struct fields - added Documentation/hwmon/gsc-hwmon.rst v3: - add voltage_raw input type and supporting fields - add channel validation to is_visible function - remove unnecessary channel validation from read/write functions v2: - change license comment style - remove DEBUG - simplify regmap_bulk_read err check - remove break after returns in switch statement - fix fan setpoint buffer address - remove unnecessary parens - consistently use struct device *dev pointer - change license/comment block - add validation for hwmon child node props - move parsing of of to own function - use strlcpy to ensure null termination - fix static array sizes and removed unnecessary initializers - dynamically allocate channels - fix fan input label - support platform data - fixed whitespace issues --- Documentation/hwmon/gsc-hwmon.rst | 53 +++++ Documentation/hwmon/index.rst | 1 + MAINTAINERS | 3 + drivers/hwmon/Kconfig | 9 + drivers/hwmon/Makefile | 1 + drivers/hwmon/gsc-hwmon.c | 390 ++++++++++++++++++++++++++++++++ include/linux/platform_data/gsc_hwmon.h | 44 ++++ 7 files changed, 501 insertions(+) create mode 100644 Documentation/hwmon/gsc-hwmon.rst create mode 100644 drivers/hwmon/gsc-hwmon.c create mode 100644 include/linux/platform_data/gsc_hwmon.h diff --git a/Documentation/hwmon/gsc-hwmon.rst b/Documentation/hwmon/gsc-hwmon.rst new file mode 100644 index 00000000..ffac392 --- /dev/null +++ b/Documentation/hwmon/gsc-hwmon.rst @@ -0,0 +1,53 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Kernel driver gsc-hwmon +======================= + +Supported chips: Gateworks GSC +Datasheet: http://trac.gateworks.com/wiki/gsc +Author: Tim Harvey <tharvey@xxxxxxxxxxxxx> + +Description: +------------ + +This driver supports hardware monitoring for the temperature sensor, +various ADC's connected to the GSC, and optional FAN controller available +on some boards. + + +Voltage Monitoring +------------------ + +The voltage inputs are scaled either internally or by the driver depending +on the GSC version and firmware. The values returned by the driver do not need +further scaling. The voltage input labels provide the voltage rail name: + +inX_input Measured voltage (mV). +inX_label Name of voltage rail. + + +Temperature Monitoring +---------------------- + +Temperatures are measured with 12-bit or 10-bit resolution and are scaled +either internally or by the driver depending on the GSC version and firmware. +The values returned by the driver reflect millidegree Celcius: + +tempX_input Measured temperature. +tempX_label Name of temperature input. + + +PWM Output Control +------------------ + +The GSC features 1 PWM output that operates in automatic mode where the +PWM value will be scalled depending on 6 temperature boundaries. +The tempeature boundaries are read-write and in millidegree Celcius and the +read-only PWM values range from 0 (off) to 255 (full speed). +Fan speed will be set to minimum (off) when the temperature sensor reads +less than pwm1_auto_point1_temp and maximum when the temperature sensor +equals or exceeds pwm1_auto_point6_temp. + +pwm1_auto_point[1-6]_pwm PWM value. +pwm1_auto_point[1-6]_temp Temperature boundary. + diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 8ef62fd..1c02aa6 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -60,6 +60,7 @@ Hardware Monitoring Kernel Drivers ftsteutates g760a g762 + gsc-hwmon gl518sm hih6130 ibmaem diff --git a/MAINTAINERS b/MAINTAINERS index c78a014..7f8ece8 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7035,6 +7035,9 @@ S: Maintained F: Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml F: drivers/mfd/gateworks-gsc.c F: include/linux/mfd/gsc.h +F: Documentation/hwmon/gsc-hwmon.rst +F: drivers/hwmon/gsc-hwmon.c +F: include/linux/platform_data/gsc_hwmon.h GASKET DRIVER FRAMEWORK M: Rob Springer <rspringer@xxxxxxxxxx> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 4c62f90..5549906 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -523,6 +523,15 @@ config SENSORS_F75375S This driver can also be built as a module. If so, the module will be called f75375s. +config SENSORS_GSC + tristate "Gateworks System Controller ADC" + depends on MFD_GATEWORKS_GSC + help + Support for the Gateworks System Controller A/D converters. + + To compile this driver as a module, choose M here: + the module will be called gsc-hwmon. + config SENSORS_MC13783_ADC tristate "Freescale MC13783/MC13892 ADC" depends on MFD_MC13XXX diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index b0b9c8e..a6564d0 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -74,6 +74,7 @@ obj-$(CONFIG_SENSORS_G760A) += g760a.o obj-$(CONFIG_SENSORS_G762) += g762.o obj-$(CONFIG_SENSORS_GL518SM) += gl518sm.o obj-$(CONFIG_SENSORS_GL520SM) += gl520sm.o +obj-$(CONFIG_SENSORS_GSC) += gsc-hwmon.o obj-$(CONFIG_SENSORS_GPIO_FAN) += gpio-fan.o obj-$(CONFIG_SENSORS_HIH6130) += hih6130.o obj-$(CONFIG_SENSORS_ULTRA45) += ultra45_env.o diff --git a/drivers/hwmon/gsc-hwmon.c b/drivers/hwmon/gsc-hwmon.c new file mode 100644 index 00000000..2137bc6 --- /dev/null +++ b/drivers/hwmon/gsc-hwmon.c @@ -0,0 +1,390 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for Gateworks System Controller Hardware Monitor module + * + * Copyright (C) 2020 Gateworks Corporation + */ +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/mfd/gsc.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#include <linux/platform_data/gsc_hwmon.h> + +#define GSC_HWMON_MAX_TEMP_CH 16 +#define GSC_HWMON_MAX_IN_CH 16 + +#define GSC_HWMON_RESOLUTION 12 +#define GSC_HWMON_VREF 2500 + +struct gsc_hwmon_data { + struct gsc_dev *gsc; + struct gsc_hwmon_platform_data *pdata; + struct regmap *regmap; + const struct gsc_hwmon_channel *temp_ch[GSC_HWMON_MAX_TEMP_CH]; + const struct gsc_hwmon_channel *in_ch[GSC_HWMON_MAX_IN_CH]; + u32 temp_config[GSC_HWMON_MAX_TEMP_CH + 1]; + u32 in_config[GSC_HWMON_MAX_IN_CH + 1]; + struct hwmon_channel_info temp_info; + struct hwmon_channel_info in_info; + const struct hwmon_channel_info *info[3]; + struct hwmon_chip_info chip; +}; + +static struct regmap_bus gsc_hwmon_regmap_bus = { + .reg_read = gsc_read, + .reg_write = gsc_write, +}; + +static const struct regmap_config gsc_hwmon_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .cache_type = REGCACHE_NONE, +}; + +static ssize_t pwm_auto_point_temp_show(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + u8 reg = hwmon->pdata->fan_base + (2 * attr->index); + u8 regs[2]; + int ret; + + ret = regmap_bulk_read(hwmon->regmap, reg, regs, 2); + if (ret) + return ret; + + ret = regs[0] | regs[1] << 8; + return sprintf(buf, "%d\n", ret * 10); +} + +static ssize_t pwm_auto_point_temp_store(struct device *dev, + struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + u8 reg = hwmon->pdata->fan_base + (2 * attr->index); + u8 regs[2]; + long temp; + int err; + + if (kstrtol(buf, 10, &temp)) + return -EINVAL; + + temp = clamp_val(temp, 0, 10000); + temp = DIV_ROUND_CLOSEST(temp, 10); + + regs[0] = temp & 0xff; + regs[1] = (temp >> 8) & 0xff; + err = regmap_bulk_write(hwmon->regmap, reg, regs, 2); + if (err) + return err; + + return count; +} + +static ssize_t pwm_auto_point_pwm_show(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + + return sprintf(buf, "%d\n", 255 * (50 + (attr->index * 10)) / 100); +} + +static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm_auto_point_pwm, 0); +static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp, pwm_auto_point_temp, 0); + +static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point2_pwm, pwm_auto_point_pwm, 1); +static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp, pwm_auto_point_temp, 1); + +static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm_auto_point_pwm, 2); +static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp, pwm_auto_point_temp, 2); + +static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point4_pwm, pwm_auto_point_pwm, 3); +static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp, pwm_auto_point_temp, 3); + +static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm_auto_point_pwm, 4); +static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point5_temp, pwm_auto_point_temp, 4); + +static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point6_pwm, pwm_auto_point_pwm, 5); +static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point6_temp, pwm_auto_point_temp, 5); + +static struct attribute *gsc_hwmon_attributes[] = { + &sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point6_pwm.dev_attr.attr, + &sensor_dev_attr_pwm1_auto_point6_temp.dev_attr.attr, + NULL +}; + +static const struct attribute_group gsc_hwmon_group = { + .attrs = gsc_hwmon_attributes, +}; +__ATTRIBUTE_GROUPS(gsc_hwmon); + +static int +gsc_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, + int channel, long *val) +{ + struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); + const struct gsc_hwmon_channel *ch; + int sz, ret; + long tmp; + u8 buf[3]; + + switch (type) { + case hwmon_in: + ch = hwmon->in_ch[channel]; + break; + case hwmon_temp: + ch = hwmon->temp_ch[channel]; + break; + default: + return -EOPNOTSUPP; + } + + sz = (ch->mode == mode_voltage) ? 3 : 2; + ret = regmap_bulk_read(hwmon->regmap, ch->reg, buf, sz); + if (ret) + return ret; + + tmp = 0; + while (sz-- > 0) + tmp |= (buf[sz] << (8 * sz)); + + switch (ch->mode) { + case mode_temperature: + if (tmp > 0x8000) + tmp -= 0xffff; + break; + case mode_voltage_raw: + tmp = clamp_val(tmp, 0, BIT(GSC_HWMON_RESOLUTION)); + /* scale based on ref voltage and ADC resolution */ + tmp *= GSC_HWMON_VREF; + tmp >>= GSC_HWMON_RESOLUTION; + /* scale based on optional voltage divider */ + if (ch->vdiv[0] && ch->vdiv[1]) { + tmp *= (ch->vdiv[0] + ch->vdiv[1]); + tmp /= ch->vdiv[1]; + } + /* adjust by uV offset */ + tmp += ch->mvoffset; + break; + case mode_voltage: + /* no adjustment needed */ + break; + } + + *val = tmp; + + return 0; +} + +static int +gsc_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, const char **buf) +{ + struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); + + switch (type) { + case hwmon_in: + *buf = hwmon->in_ch[channel]->name; + break; + case hwmon_temp: + *buf = hwmon->temp_ch[channel]->name; + break; + default: + return -ENOTSUPP; + } + + return 0; +} + +static umode_t +gsc_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr, + int ch) +{ + return 0444; +} + +static const struct hwmon_ops gsc_hwmon_ops = { + .is_visible = gsc_hwmon_is_visible, + .read = gsc_hwmon_read, + .read_string = gsc_hwmon_read_string, +}; + +static struct gsc_hwmon_platform_data * +gsc_hwmon_get_devtree_pdata(struct device *dev) +{ + struct gsc_hwmon_platform_data *pdata; + struct gsc_hwmon_channel *ch; + struct fwnode_handle *child; + struct device_node *fan; + int nchannels; + + nchannels = device_get_child_node_count(dev); + if (nchannels == 0) + return ERR_PTR(-ENODEV); + + pdata = devm_kzalloc(dev, + sizeof(*pdata) + nchannels * sizeof(*ch), + GFP_KERNEL); + if (!pdata) + return ERR_PTR(-ENOMEM); + ch = (struct gsc_hwmon_channel *)(pdata + 1); + pdata->channels = ch; + pdata->nchannels = nchannels; + + /* fan controller base address */ + fan = of_find_compatible_node(dev->parent->of_node, NULL, "gw,gsc-fan"); + if (fan && of_property_read_u32(fan, "reg", &pdata->fan_base)) { + dev_err(dev, "fan node without base\n"); + return ERR_PTR(-EINVAL); + } + + /* allocate structures for channels and count instances of each type */ + device_for_each_child_node(dev, child) { + if (fwnode_property_read_string(child, "label", &ch->name)) { + dev_err(dev, "channel without label\n"); + fwnode_handle_put(child); + return ERR_PTR(-EINVAL); + } + if (fwnode_property_read_u32(child, "reg", &ch->reg)) { + dev_err(dev, "channel without reg\n"); + fwnode_handle_put(child); + return ERR_PTR(-EINVAL); + } + if (fwnode_property_read_u32(child, "gw,mode", &ch->mode)) { + dev_err(dev, "channel without mode\n"); + fwnode_handle_put(child); + return ERR_PTR(-EINVAL); + } + if (ch->mode > mode_max) { + dev_err(dev, "invalid channel mode\n"); + fwnode_handle_put(child); + return ERR_PTR(-EINVAL); + } + + if (!fwnode_property_read_u32(child, + "gw,voltage-offset-microvolt", + &ch->mvoffset)) + ch->mvoffset /= 1000; + fwnode_property_read_u32_array(child, + "gw,voltage-divider-ohms", + ch->vdiv, ARRAY_SIZE(ch->vdiv)); + ch++; + } + + return pdata; +} + +static int gsc_hwmon_probe(struct platform_device *pdev) +{ + struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct device *hwmon_dev; + struct gsc_hwmon_platform_data *pdata = dev_get_platdata(dev); + struct gsc_hwmon_data *hwmon; + const struct attribute_group **groups; + int i, i_in, i_temp; + + if (!pdata) { + pdata = gsc_hwmon_get_devtree_pdata(dev); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + } + + hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL); + if (!hwmon) + return -ENOMEM; + hwmon->gsc = gsc; + hwmon->pdata = pdata; + + hwmon->regmap = devm_regmap_init(dev, &gsc_hwmon_regmap_bus, + gsc->i2c_hwmon, + &gsc_hwmon_regmap_config); + if (IS_ERR(hwmon->regmap)) + return PTR_ERR(hwmon->regmap); + + for (i = 0, i_in = 0, i_temp = 0; i < hwmon->pdata->nchannels; i++) { + const struct gsc_hwmon_channel *ch = &pdata->channels[i]; + + switch (ch->mode) { + case mode_temperature: + if (i_temp == GSC_HWMON_MAX_TEMP_CH) { + dev_err(gsc->dev, "too many temp channels\n"); + return -EINVAL; + } + hwmon->temp_ch[i_temp] = ch; + hwmon->temp_config[i_temp] = HWMON_T_INPUT | + HWMON_T_LABEL; + i_temp++; + break; + case mode_voltage: + case mode_voltage_raw: + if (i_in == GSC_HWMON_MAX_IN_CH) { + dev_err(gsc->dev, "too many input channels\n"); + return -EINVAL; + } + hwmon->in_ch[i_in] = ch; + hwmon->in_config[i_in] = + HWMON_I_INPUT | HWMON_I_LABEL; + i_in++; + break; + default: + dev_err(gsc->dev, "invalid mode: %d\n", ch->mode); + return -EINVAL; + } + } + + /* setup config structures */ + hwmon->chip.ops = &gsc_hwmon_ops; + hwmon->chip.info = hwmon->info; + hwmon->info[0] = &hwmon->temp_info; + hwmon->info[1] = &hwmon->in_info; + hwmon->temp_info.type = hwmon_temp; + hwmon->temp_info.config = hwmon->temp_config; + hwmon->in_info.type = hwmon_in; + hwmon->in_info.config = hwmon->in_config; + + groups = pdata->fan_base ? gsc_hwmon_groups : NULL; + hwmon_dev = devm_hwmon_device_register_with_info(dev, + KBUILD_MODNAME, hwmon, + &hwmon->chip, groups); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct of_device_id gsc_hwmon_of_match[] = { + { .compatible = "gw,gsc-adc", }, + {} +}; + +static struct platform_driver gsc_hwmon_driver = { + .driver = { + .name = "gsc-hwmon", + .of_match_table = gsc_hwmon_of_match, + }, + .probe = gsc_hwmon_probe, +}; + +module_platform_driver(gsc_hwmon_driver); + +MODULE_AUTHOR("Tim Harvey <tharvey@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("GSC hardware monitor driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/platform_data/gsc_hwmon.h b/include/linux/platform_data/gsc_hwmon.h new file mode 100644 index 00000000..ec1611a --- /dev/null +++ b/include/linux/platform_data/gsc_hwmon.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _GSC_HWMON_H +#define _GSC_HWMON_H + +enum gsc_hwmon_mode { + mode_temperature, + mode_voltage, + mode_voltage_raw, + mode_max, +}; + +/** + * struct gsc_hwmon_channel - configuration parameters + * @reg: I2C register offset + * @mode: channel mode + * @name: channel name + * @mvoffset: voltage offset + * @vdiv: voltage divider array (2 resistor values in milli-ohms) + */ +struct gsc_hwmon_channel { + unsigned int reg; + unsigned int mode; + const char *name; + unsigned int mvoffset; + unsigned int vdiv[2]; +}; + +/** + * struct gsc_hwmon_platform_data - platform data for gsc_hwmon driver + * @channels: pointer to array of gsc_hwmon_channel structures + * describing channels + * @nchannels: number of elements in @channels array + * @vreference: voltage reference (mV) + * @resolution: ADC bit resolution + * @fan_base: register base for FAN controller + */ +struct gsc_hwmon_platform_data { + const struct gsc_hwmon_channel *channels; + int nchannels; + unsigned int resolution; + unsigned int vreference; + unsigned int fan_base; +}; +#endif -- 2.7.4