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-rw-r--r--Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml196
-rw-r--r--Documentation/hwmon/gsc-hwmon.rst53
-rw-r--r--Documentation/hwmon/index.rst1
-rw-r--r--MAINTAINERS11
-rw-r--r--drivers/hwmon/Kconfig9
-rw-r--r--drivers/hwmon/Makefile1
-rw-r--r--drivers/hwmon/gsc-hwmon.c390
-rw-r--r--drivers/mfd/Kconfig15
-rw-r--r--drivers/mfd/Makefile1
-rw-r--r--drivers/mfd/gateworks-gsc.c277
-rw-r--r--include/linux/mfd/gsc.h76
-rw-r--r--include/linux/platform_data/gsc_hwmon.h44
12 files changed, 1074 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml b/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
new file mode 100644
index 000000000000..487a8445722e
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
@@ -0,0 +1,196 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/gateworks-gsc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Gateworks System Controller
+
+description: |
+ The Gateworks System Controller (GSC) is a device present across various
+ Gateworks product families that provides a set of system related features
+ such as the following (refer to the board hardware user manuals to see what
+ features are present)
+ - Watchdog Timer
+ - GPIO
+ - Pushbutton controller
+ - Hardware monitor with ADC's for temperature and voltage rails and
+ fan controller
+
+maintainers:
+ - Tim Harvey <tharvey@gateworks.com>
+ - Robert Jones <rjones@gateworks.com>
+
+properties:
+ $nodename:
+ pattern: "gsc@[0-9a-f]{1,2}"
+ compatible:
+ const: gw,gsc
+
+ reg:
+ description: I2C device address
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ interrupt-controller: true
+
+ "#interrupt-cells":
+ const: 1
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+ adc:
+ type: object
+ description: Optional hardware monitoring module
+
+ properties:
+ compatible:
+ const: gw,gsc-adc
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+ patternProperties:
+ "^channel@[0-9]+$":
+ type: object
+ description: |
+ Properties for a single ADC which can report cooked values
+ (i.e. temperature sensor based on thermister), raw values
+ (i.e. voltage rail with a pre-scaling resistor divider).
+
+ properties:
+ reg:
+ description: Register of the ADC
+ maxItems: 1
+
+ label:
+ description: Name of the ADC input
+
+ gw,mode:
+ description: |
+ conversion mode:
+ 0 - temperature, in C*10
+ 1 - pre-scaled voltage value
+ 2 - scaled voltage based on an optional resistor divider
+ and optional offset
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [0, 1, 2]
+
+ gw,voltage-divider-ohms:
+ description: Values of resistors for divider on raw ADC input
+ maxItems: 2
+ items:
+ minimum: 1000
+ maximum: 1000000
+
+ gw,voltage-offset-microvolt:
+ description: |
+ A positive voltage offset to apply to a raw ADC
+ (i.e. to compensate for a diode drop).
+ minimum: 0
+ maximum: 1000000
+
+ required:
+ - gw,mode
+ - reg
+ - label
+
+ required:
+ - compatible
+ - "#address-cells"
+ - "#size-cells"
+
+patternProperties:
+ "^fan-controller@[0-9a-f]+$":
+ type: object
+ description: Optional fan controller
+
+ properties:
+ compatible:
+ const: gw,gsc-fan
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+ reg:
+ description: The fan controller base address
+ maxItems: 1
+
+ required:
+ - compatible
+ - reg
+ - "#address-cells"
+ - "#size-cells"
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - interrupt-controller
+ - "#interrupt-cells"
+ - "#address-cells"
+ - "#size-cells"
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ gsc@20 {
+ compatible = "gw,gsc";
+ reg = <0x20>;
+ interrupt-parent = <&gpio1>;
+ interrupts = <4 GPIO_ACTIVE_LOW>;
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ adc {
+ compatible = "gw,gsc-adc";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ channel@0 { /* A0: Board Temperature */
+ reg = <0x00>;
+ label = "temp";
+ gw,mode = <0>;
+ };
+
+ channel@2 { /* A1: Input Voltage (raw ADC) */
+ reg = <0x02>;
+ label = "vdd_vin";
+ gw,mode = <1>;
+ gw,voltage-divider-ohms = <22100 1000>;
+ gw,voltage-offset-microvolt = <800000>;
+ };
+
+ channel@b { /* A2: Battery voltage */
+ reg = <0x0b>;
+ label = "vdd_bat";
+ gw,mode = <1>;
+ };
+ };
+
+ fan-controller@2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "gw,gsc-fan";
+ reg = <0x2c>;
+ };
+ };
+ };
diff --git a/Documentation/hwmon/gsc-hwmon.rst b/Documentation/hwmon/gsc-hwmon.rst
new file mode 100644
index 000000000000..ffac392a7129
--- /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@gateworks.com>
+
+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 fb51c7ce8b27..e463fa9a219d 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -61,6 +61,7 @@ Hardware Monitoring Kernel Drivers
ftsteutates
g760a
g762
+ gsc-hwmon
gl518sm
hih6130
ibmaem
diff --git a/MAINTAINERS b/MAINTAINERS
index 2b1591875abf..bd6f9b6f55e3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7035,6 +7035,17 @@ F: kernel/futex.c
F: tools/perf/bench/futex*
F: tools/testing/selftests/futex/
+GATEWORKS SYSTEM CONTROLLER (GSC) DRIVER
+M: Tim Harvey <tharvey@gateworks.com>
+M: Robert Jones <rjones@gateworks.com>
+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@google.com>
M: Todd Poynor <toddpoynor@google.com>
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 2362be5a5b11..3ae303d6c12b 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -533,6 +533,15 @@ 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 318f89dc7133..892174f18f6b 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -75,6 +75,7 @@ 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 000000000000..2137bc65829d
--- /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@gateworks.com>");
+MODULE_DESCRIPTION("GSC hardware monitor driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 0a59249198d3..05448e78e5b8 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -407,6 +407,21 @@ config MFD_EXYNOS_LPASS
Select this option to enable support for Samsung Exynos Low Power
Audio Subsystem.
+config MFD_GATEWORKS_GSC
+ tristate "Gateworks System Controller"
+ depends on (I2C && OF)
+ select MFD_CORE
+ select REGMAP_I2C
+ select REGMAP_IRQ
+ help
+ Enable support for the Gateworks System Controller (GSC) found
+ on Gateworks Single Board Computers supporting system functions
+ such as push-button monitor, multiple ADC's for voltage and
+ temperature monitoring, fan controller and watchdog monitor.
+ This driver provides common support for accessing the device.
+ Additional drivers must be enabled in order to use the
+ functionality of the device.
+
config MFD_MC13XXX
tristate
depends on (SPI_MASTER || I2C)
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index f935d10cbf0f..ed433aed7010 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o
obj-$(CONFIG_MFD_BD9571MWV) += bd9571mwv.o
obj-$(CONFIG_MFD_CROS_EC_DEV) += cros_ec_dev.o
obj-$(CONFIG_MFD_EXYNOS_LPASS) += exynos-lpass.o
+obj-$(CONFIG_MFD_GATEWORKS_GSC) += gateworks-gsc.o
obj-$(CONFIG_HTC_PASIC3) += htc-pasic3.o
obj-$(CONFIG_HTC_I2CPLD) += htc-i2cpld.o
diff --git a/drivers/mfd/gateworks-gsc.c b/drivers/mfd/gateworks-gsc.c
new file mode 100644
index 000000000000..576da62fbb0c
--- /dev/null
+++ b/drivers/mfd/gateworks-gsc.c
@@ -0,0 +1,277 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * The Gateworks System Controller (GSC) is a multi-function
+ * device designed for use in Gateworks Single Board Computers.
+ * The control interface is I2C, with an interrupt. The device supports
+ * system functions such as push-button monitoring, multiple ADC's for
+ * voltage and temperature monitoring, fan controller and watchdog monitor.
+ *
+ * Copyright (C) 2020 Gateworks Corporation
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/gsc.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <asm/unaligned.h>
+
+/*
+ * The GSC suffers from an errata where occasionally during
+ * ADC cycles the chip can NAK I2C transactions. To ensure we have reliable
+ * register access we place retries around register access.
+ */
+#define I2C_RETRIES 3
+
+int gsc_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct i2c_client *client = context;
+ int retry, ret;
+
+ for (retry = 0; retry < I2C_RETRIES; retry++) {
+ ret = i2c_smbus_write_byte_data(client, reg, val);
+ /*
+ * -EAGAIN returned when the i2c host controller is busy
+ * -EIO returned when i2c device is busy
+ */
+ if (ret != -EAGAIN && ret != -EIO)
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gsc_write);
+
+int gsc_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct i2c_client *client = context;
+ int retry, ret;
+
+ for (retry = 0; retry < I2C_RETRIES; retry++) {
+ ret = i2c_smbus_read_byte_data(client, reg);
+ /*
+ * -EAGAIN returned when the i2c host controller is busy
+ * -EIO returned when i2c device is busy
+ */
+ if (ret != -EAGAIN && ret != -EIO)
+ break;
+ }
+ *val = ret & 0xff;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gsc_read);
+
+/*
+ * gsc_powerdown - API to use GSC to power down board for a specific time
+ *
+ * secs - number of seconds to remain powered off
+ */
+static int gsc_powerdown(struct gsc_dev *gsc, unsigned long secs)
+{
+ int ret;
+ unsigned char regs[4];
+
+ dev_info(&gsc->i2c->dev, "GSC powerdown for %ld seconds\n",
+ secs);
+
+ put_unaligned_le32(secs, regs);
+ ret = regmap_bulk_write(gsc->regmap, GSC_TIME_ADD, regs, 4);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(gsc->regmap, GSC_CTRL_1,
+ BIT(GSC_CTRL_1_SLEEP_ADD),
+ BIT(GSC_CTRL_1_SLEEP_ADD));
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(gsc->regmap, GSC_CTRL_1,
+ BIT(GSC_CTRL_1_SLEEP_ACTIVATE) |
+ BIT(GSC_CTRL_1_SLEEP_ENABLE),
+ BIT(GSC_CTRL_1_SLEEP_ACTIVATE) |
+ BIT(GSC_CTRL_1_SLEEP_ENABLE));
+
+
+ return ret;
+}
+
+static ssize_t gsc_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct gsc_dev *gsc = dev_get_drvdata(dev);
+ const char *name = attr->attr.name;
+ int rz = 0;
+
+ if (strcasecmp(name, "fw_version") == 0)
+ rz = sprintf(buf, "%d\n", gsc->fwver);
+ else if (strcasecmp(name, "fw_crc") == 0)
+ rz = sprintf(buf, "0x%04x\n", gsc->fwcrc);
+ else
+ dev_err(dev, "invalid command: '%s'\n", name);
+
+ return rz;
+}
+
+static ssize_t gsc_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct gsc_dev *gsc = dev_get_drvdata(dev);
+ const char *name = attr->attr.name;
+ long value;
+
+ if (strcasecmp(name, "powerdown") == 0) {
+ if (kstrtol(buf, 0, &value) == 0)
+ gsc_powerdown(gsc, value);
+ } else {
+ dev_err(dev, "invalid command: '%s\n", name);
+ }
+
+ return count;
+}
+
+static struct device_attribute attr_fwver =
+ __ATTR(fw_version, 0440, gsc_show, NULL);
+static struct device_attribute attr_fwcrc =
+ __ATTR(fw_crc, 0440, gsc_show, NULL);
+static struct device_attribute attr_pwrdown =
+ __ATTR(powerdown, 0220, NULL, gsc_store);
+
+static struct attribute *gsc_attrs[] = {
+ &attr_fwver.attr,
+ &attr_fwcrc.attr,
+ &attr_pwrdown.attr,
+ NULL,
+};
+
+static struct attribute_group attr_group = {
+ .attrs = gsc_attrs,
+};
+
+static const struct of_device_id gsc_of_match[] = {
+ { .compatible = "gw,gsc", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, gsc_of_match);
+
+static struct regmap_bus gsc_regmap_bus = {
+ .reg_read = gsc_read,
+ .reg_write = gsc_write,
+};
+
+static const struct regmap_config gsc_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .cache_type = REGCACHE_NONE,
+ .max_register = GSC_WP,
+};
+
+static const struct regmap_irq gsc_irqs[] = {
+ REGMAP_IRQ_REG(GSC_IRQ_PB, 0, BIT(GSC_IRQ_PB)),
+ REGMAP_IRQ_REG(GSC_IRQ_KEY_ERASED, 0, BIT(GSC_IRQ_KEY_ERASED)),
+ REGMAP_IRQ_REG(GSC_IRQ_EEPROM_WP, 0, BIT(GSC_IRQ_EEPROM_WP)),
+ REGMAP_IRQ_REG(GSC_IRQ_RESV, 0, BIT(GSC_IRQ_RESV)),
+ REGMAP_IRQ_REG(GSC_IRQ_GPIO, 0, BIT(GSC_IRQ_GPIO)),
+ REGMAP_IRQ_REG(GSC_IRQ_TAMPER, 0, BIT(GSC_IRQ_TAMPER)),
+ REGMAP_IRQ_REG(GSC_IRQ_WDT_TIMEOUT, 0, BIT(GSC_IRQ_WDT_TIMEOUT)),
+ REGMAP_IRQ_REG(GSC_IRQ_SWITCH_HOLD, 0, BIT(GSC_IRQ_SWITCH_HOLD)),
+};
+
+static const struct regmap_irq_chip gsc_irq_chip = {
+ .name = "gateworks-gsc",
+ .irqs = gsc_irqs,
+ .num_irqs = ARRAY_SIZE(gsc_irqs),
+ .num_regs = 1,
+ .status_base = GSC_IRQ_STATUS,
+ .mask_base = GSC_IRQ_ENABLE,
+ .mask_invert = true,
+ .ack_base = GSC_IRQ_STATUS,
+ .ack_invert = true,
+};
+
+static int gsc_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct gsc_dev *gsc;
+ struct regmap_irq_chip_data *irq_data;
+ int ret;
+ unsigned int reg;
+
+ gsc = devm_kzalloc(dev, sizeof(*gsc), GFP_KERNEL);
+ if (!gsc)
+ return -ENOMEM;
+
+ gsc->dev = &client->dev;
+ gsc->i2c = client;
+ i2c_set_clientdata(client, gsc);
+
+ gsc->regmap = devm_regmap_init(dev, &gsc_regmap_bus, client,
+ &gsc_regmap_config);
+ if (IS_ERR(gsc->regmap))
+ return PTR_ERR(gsc->regmap);
+
+ if (regmap_read(gsc->regmap, GSC_FW_VER, &reg))
+ return -EIO;
+ gsc->fwver = reg;
+
+ regmap_read(gsc->regmap, GSC_FW_CRC, &reg);
+ gsc->fwcrc = reg;
+ regmap_read(gsc->regmap, GSC_FW_CRC + 1, &reg);
+ gsc->fwcrc |= reg << 8;
+
+ gsc->i2c_hwmon = devm_i2c_new_dummy_device(dev, client->adapter,
+ GSC_HWMON);
+ if (IS_ERR(gsc->i2c_hwmon)) {
+ dev_err(dev, "Failed to allocate I2C device for HWMON\n");
+ return PTR_ERR(gsc->i2c_hwmon);
+ }
+
+ ret = devm_regmap_add_irq_chip(dev, gsc->regmap, client->irq,
+ IRQF_ONESHOT | IRQF_SHARED |
+ IRQF_TRIGGER_FALLING, 0,
+ &gsc_irq_chip, &irq_data);
+ if (ret)
+ return ret;
+
+ dev_info(dev, "Gateworks System Controller v%d: fw 0x%04x\n",
+ gsc->fwver, gsc->fwcrc);
+
+ ret = sysfs_create_group(&dev->kobj, &attr_group);
+ if (ret)
+ dev_err(dev, "failed to create sysfs attrs\n");
+
+ ret = devm_of_platform_populate(dev);
+ if (ret) {
+ sysfs_remove_group(&dev->kobj, &attr_group);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int gsc_remove(struct i2c_client *client)
+{
+ sysfs_remove_group(&client->dev.kobj, &attr_group);
+
+ return 0;
+}
+
+static struct i2c_driver gsc_driver = {
+ .driver = {
+ .name = "gateworks-gsc",
+ .of_match_table = gsc_of_match,
+ },
+ .probe_new = gsc_probe,
+ .remove = gsc_remove,
+};
+module_i2c_driver(gsc_driver);
+
+MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>");
+MODULE_DESCRIPTION("I2C Core interface for GSC");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/gsc.h b/include/linux/mfd/gsc.h
new file mode 100644
index 000000000000..6bd639c285b4
--- /dev/null
+++ b/include/linux/mfd/gsc.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2020 Gateworks Corporation
+ */
+#ifndef __LINUX_MFD_GSC_H_
+#define __LINUX_MFD_GSC_H_
+
+#include <linux/regmap.h>
+
+/* Device Addresses */
+#define GSC_MISC 0x20
+#define GSC_UPDATE 0x21
+#define GSC_GPIO 0x23
+#define GSC_HWMON 0x29
+#define GSC_EEPROM0 0x50
+#define GSC_EEPROM1 0x51
+#define GSC_EEPROM2 0x52
+#define GSC_EEPROM3 0x53
+#define GSC_RTC 0x68
+
+/* Register offsets */
+enum {
+ GSC_CTRL_0 = 0x00,
+ GSC_CTRL_1 = 0x01,
+ GSC_TIME = 0x02,
+ GSC_TIME_ADD = 0x06,
+ GSC_IRQ_STATUS = 0x0A,
+ GSC_IRQ_ENABLE = 0x0B,
+ GSC_FW_CRC = 0x0C,
+ GSC_FW_VER = 0x0E,
+ GSC_WP = 0x0F,
+};
+
+/* Bit definitions */
+#define GSC_CTRL_0_PB_HARD_RESET 0
+#define GSC_CTRL_0_PB_CLEAR_SECURE_KEY 1
+#define GSC_CTRL_0_PB_SOFT_POWER_DOWN 2
+#define GSC_CTRL_0_PB_BOOT_ALTERNATE 3
+#define GSC_CTRL_0_PERFORM_CRC 4
+#define GSC_CTRL_0_TAMPER_DETECT 5
+#define GSC_CTRL_0_SWITCH_HOLD 6
+
+#define GSC_CTRL_1_SLEEP_ENABLE 0
+#define GSC_CTRL_1_SLEEP_ACTIVATE 1
+#define GSC_CTRL_1_SLEEP_ADD 2
+#define GSC_CTRL_1_SLEEP_NOWAKEPB 3
+#define GSC_CTRL_1_WDT_TIME 4
+#define GSC_CTRL_1_WDT_ENABLE 5
+#define GSC_CTRL_1_SWITCH_BOOT_ENABLE 6
+#define GSC_CTRL_1_SWITCH_BOOT_CLEAR 7
+
+#define GSC_IRQ_PB 0
+#define GSC_IRQ_KEY_ERASED 1
+#define GSC_IRQ_EEPROM_WP 2
+#define GSC_IRQ_RESV 3
+#define GSC_IRQ_GPIO 4
+#define GSC_IRQ_TAMPER 5
+#define GSC_IRQ_WDT_TIMEOUT 6
+#define GSC_IRQ_SWITCH_HOLD 7
+
+int gsc_read(void *context, unsigned int reg, unsigned int *val);
+int gsc_write(void *context, unsigned int reg, unsigned int val);
+
+struct gsc_dev {
+ struct device *dev;
+
+ struct i2c_client *i2c; /* 0x20: interrupt controller, WDT */
+ struct i2c_client *i2c_hwmon; /* 0x29: hwmon, fan controller */
+
+ struct regmap *regmap;
+
+ unsigned int fwver;
+ unsigned short fwcrc;
+};
+
+#endif /* __LINUX_MFD_GSC_H_ */
diff --git a/include/linux/platform_data/gsc_hwmon.h b/include/linux/platform_data/gsc_hwmon.h
new file mode 100644
index 000000000000..ec1611aff863
--- /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
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.