This series adds support for the Gateworks System Controller used on Gateworks
Laguna, Ventana, and Newport product families.
The GSC is an MSP430 I2C slave controller whose firmware embeds the following
features:
- I/O expander (16 GPIO's emulating a PCA955x)
- EEPROM (enumating AT24)
- RTC (enumating DS1672)
- HWMON
- Interrupt controller with tamper detect, user pushbotton
- Watchdog controller capable of full board power-cycle
- Power Control capable of full board power-cycle
see http://trac.gateworks.com/wiki/gsc for more details
---
v6:
- hwmon: fix size of info field
- hwmon: improve pwm output control documentation
- hwmon: include unit suffix in divider and offset
- hwmon: change subnode name to gsc-adc
- hwmon: change to fan subnode
- hwmon: fix voltage offset
- dt-bindings: fix commit message typo
- dt-bindings: drop invalid description from #interrupt-cells property
- dt-bindings: fix adc pattern property
- dt-bindings: add unit suffix
- dt-bindings: replace hwmon/adc with adc/channel
- dt-bindings: changed adc type to gw,mode
- dt-bindings: add unit suffix and drop ref for voltage-divider
- dt-bindings: add unit suffix for voltage-offset
- dt-bindings: moved fan to its own subnode with base register
v5:
- fix checkpatch issues
- fix dt_binding_check issues
- address feedback from v4
v4:
- hwmon: move to using pwm<n>_auto_point<m>_{pwm,temp} for FAN PWM
- hwmon: remove unncessary resolution/scaling properties for ADCs
- bindings: update to yaml Documentation
- removed watchdog driver
v3:
- removed unnecessary input driver
- added wdt driver
- bindings: encorporated feedback from mailng list
- hwmon:
- encoroprated feedback from mailng list
- added support for raw ADC voltage input used in newer GSC firmware
v2:
- change license comment block style
- remove COMPILE_TEST
- fixed whitespace issues
- replaced a printk with dev_err
- 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
- 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
Tim Harvey (3):
dt-bindings: mfd: Add Gateworks System Controller bindings
mfd: add Gateworks System Controller core driver
hwmon: add Gateworks System Controller support
.../devicetree/bindings/mfd/gateworks-gsc.yaml | 172 ++++++++++
Documentation/hwmon/gsc-hwmon.rst | 53 +++
Documentation/hwmon/index.rst | 1 +
MAINTAINERS | 11 +
drivers/hwmon/Kconfig | 9 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/gsc-hwmon.c | 372 +++++++++++++++++++++
drivers/mfd/Kconfig | 10 +
drivers/mfd/Makefile | 1 +
drivers/mfd/gateworks-gsc.c | 292 ++++++++++++++++
include/linux/mfd/gsc.h | 72 ++++
include/linux/platform_data/gsc_hwmon.h | 44 +++
12 files changed, 1038 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
create mode 100644 Documentation/hwmon/gsc-hwmon.rst
create mode 100644 drivers/hwmon/gsc-hwmon.c
create mode 100644 drivers/mfd/gateworks-gsc.c
create mode 100644 include/linux/mfd/gsc.h
create mode 100644 include/linux/platform_data/gsc_hwmon.h
--
2.7.4
The Gateworks System Controller (GSC) is an I2C slave controller
implemented with an MSP430 micro-controller whose firmware embeds the
following features:
- I/O expander (16 GPIO's) using PCA955x protocol
- Real Time Clock using DS1672 protocol
- User EEPROM using AT24 protocol
- HWMON using custom protocol
- Interrupt controller with tamper detect, user pushbotton
- Watchdog controller capable of full board power-cycle
- Power Control capable of full board power-cycle
see http://trac.gateworks.com/wiki/gsc for more details
Cc: Randy Dunlap <[email protected]>
Signed-off-by: Tim Harvey <[email protected]>
---
v6:
- remove duplicate signature and fix commit log
v5:
- simplify powerdown function
v4:
- remove hwmon max reg check/define
- fix powerdown function
v3:
- rename gsc->gateworks-gsc
- remove uncecessary include for linux/mfd/core.h
- upercase I2C in comments
- remove i2c debug
- remove uncecessary comments
- don't use KBUILD_MODNAME for name
- remove unnecessary v1/v2/v3 tracking
- unregister hwmon i2c adapter on remove
v2:
- change license comment block style
- remove COMPILE_TEST (Randy)
- fixed whitespace issues
- replaced a printk with dev_err
---
MAINTAINERS | 8 ++
drivers/mfd/Kconfig | 10 ++
drivers/mfd/Makefile | 1 +
drivers/mfd/gateworks-gsc.c | 292 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/mfd/gsc.h | 72 +++++++++++
5 files changed, 383 insertions(+)
create mode 100644 drivers/mfd/gateworks-gsc.c
create mode 100644 include/linux/mfd/gsc.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 56765f5..bb79b60 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6839,6 +6839,14 @@ F: tools/testing/selftests/futex/
F: tools/perf/bench/futex*
F: Documentation/*futex*
+GATEWORKS SYSTEM CONTROLLER (GSC) DRIVER
+M: Tim Harvey <[email protected]>
+M: Robert Jones <[email protected]>
+S: Maintained
+F: Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
+F: drivers/mfd/gateworks-gsc.c
+F: include/linux/mfd/gsc.h
+
GCC PLUGINS
M: Kees Cook <[email protected]>
R: Emese Revfy <[email protected]>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 4209008..d84725a 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -407,6 +407,16 @@ 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 found
+ on Gateworks Single Board Computers.
+
config MFD_MC13XXX
tristate
depends on (SPI_MASTER || I2C)
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index aed99f0..c82b442 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 00000000..f22fa63
--- /dev/null
+++ b/drivers/mfd/gateworks-gsc.c
@@ -0,0 +1,292 @@
+// 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 pushbutton monitoring, multiple ADC's for
+ * voltage and temperature, 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>
+
+/*
+ * 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
+
+static int gsc_regmap_regwrite(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;
+}
+
+static int gsc_regmap_regread(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;
+}
+
+static struct regmap_bus regmap_gsc = {
+ .reg_write = gsc_regmap_regwrite,
+ .reg_read = gsc_regmap_regread,
+};
+
+/*
+ * 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);
+ regs[0] = secs & 0xff;
+ regs[1] = (secs >> 8) & 0xff;
+ regs[2] = (secs >> 16) & 0xff;
+ regs[3] = (secs >> 24) & 0xff;
+ ret = regmap_bulk_write(gsc->regmap, GSC_TIME_ADD, regs, 4);
+ if (ret)
+ return ret;
+ regs[0] = 1 << GSC_CTRL_1_LATCH_SLEEP_ADD;
+ ret = regmap_update_bits(gsc->regmap, GSC_CTRL_1, regs[0], regs[0]);
+ if (ret)
+ return ret;
+ regs[0] = (1 << GSC_CTRL_1_ACTIVATE_SLEEP) |
+ (1 << GSC_CTRL_1_SLEEP_ENABLE);
+ ret = regmap_update_bits(gsc->regmap, GSC_CTRL_1, regs[0], regs[0]);
+
+ 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);
+
+ 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 name '%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", },
+ { }
+};
+
+static const struct regmap_config gsc_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .cache_type = REGCACHE_NONE,
+ .max_register = 0xf,
+};
+
+static const struct regmap_config gsc_regmap_hwmon_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .cache_type = REGCACHE_NONE,
+};
+
+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, const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ struct gsc_dev *gsc;
+ int ret;
+ unsigned int reg;
+
+ gsc = devm_kzalloc(dev, sizeof(*gsc), GFP_KERNEL);
+ if (!gsc)
+ return -ENOMEM;
+
+ gsc->dev = &client->dev;
+ gsc->i2c = client;
+ gsc->irq = client->irq;
+ i2c_set_clientdata(client, gsc);
+
+ gsc->regmap = devm_regmap_init(dev, ®map_gsc, client,
+ &gsc_regmap_config);
+ if (IS_ERR(gsc->regmap))
+ return PTR_ERR(gsc->regmap);
+
+ if (regmap_read(gsc->regmap, GSC_FW_VER, ®))
+ return -EIO;
+ gsc->fwver = reg;
+
+ regmap_read(gsc->regmap, GSC_FW_CRC, ®);
+ gsc->fwcrc = reg;
+ regmap_read(gsc->regmap, GSC_FW_CRC + 1, ®);
+ gsc->fwcrc |= reg << 8;
+
+ gsc->i2c_hwmon = i2c_new_dummy_device(client->adapter, GSC_HWMON);
+ if (!gsc->i2c_hwmon) {
+ dev_err(dev, "Failed to allocate I2C device for HWMON\n");
+ return -ENODEV;
+ }
+ i2c_set_clientdata(gsc->i2c_hwmon, gsc);
+
+ gsc->regmap_hwmon = devm_regmap_init(dev, ®map_gsc, gsc->i2c_hwmon,
+ &gsc_regmap_hwmon_config);
+ if (IS_ERR(gsc->regmap_hwmon)) {
+ ret = PTR_ERR(gsc->regmap_hwmon);
+ dev_err(dev, "failed to allocate register map: %d\n", ret);
+ goto err_regmap;
+ }
+
+ ret = devm_regmap_add_irq_chip(dev, gsc->regmap, gsc->irq,
+ IRQF_ONESHOT | IRQF_SHARED |
+ IRQF_TRIGGER_FALLING, 0,
+ &gsc_irq_chip, &gsc->irq_chip_data);
+ if (ret)
+ goto err_regmap;
+
+ 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 = of_platform_populate(dev->of_node, NULL, NULL, dev);
+ if (ret)
+ goto err_sysfs;
+
+ return 0;
+
+err_sysfs:
+ sysfs_remove_group(&dev->kobj, &attr_group);
+err_regmap:
+ i2c_unregister_device(gsc->i2c_hwmon);
+
+ return ret;
+}
+
+static int gsc_remove(struct i2c_client *client)
+{
+ struct gsc_dev *gsc = i2c_get_clientdata(client);
+
+ sysfs_remove_group(&client->dev.kobj, &attr_group);
+ i2c_unregister_device(gsc->i2c_hwmon);
+
+ return 0;
+}
+
+static struct i2c_driver gsc_driver = {
+ .driver = {
+ .name = "gateworks-gsc",
+ .of_match_table = of_match_ptr(gsc_of_match),
+ },
+ .probe = gsc_probe,
+ .remove = gsc_remove,
+};
+
+module_i2c_driver(gsc_driver);
+
+MODULE_AUTHOR("Tim Harvey <[email protected]>");
+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 00000000..ed9e92d
--- /dev/null
+++ b/include/linux/mfd/gsc.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2018 Gateworks Corporation
+ */
+#ifndef __LINUX_MFD_GSC_H_
+#define __LINUX_MFD_GSC_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 */
+#define GSC_CTRL_0 0x00
+#define GSC_CTRL_1 0x01
+#define GSC_TIME 0x02
+#define GSC_TIME_ADD 0x06
+#define GSC_IRQ_STATUS 0x0A
+#define GSC_IRQ_ENABLE 0x0B
+#define GSC_FW_CRC 0x0C
+#define GSC_FW_VER 0x0E
+#define 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_ACTIVATE_SLEEP 1
+#define GSC_CTRL_1_LATCH_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
+
+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;
+ struct regmap *regmap_hwmon;
+ struct regmap_irq_chip_data *irq_chip_data;
+
+ int irq;
+ unsigned int fwver;
+ unsigned short fwcrc;
+};
+
+#endif /* __LINUX_MFD_GSC_H_ */
--
2.7.4