I believe my latest patch (v4) addresses all the comments except for the use of the pm_notifier API. This API was used because I need the whole system sleep status to be sent to the controller, so that it can correctly control the power button state. If I can get the same information through PM callbacks, please confirm and I will switch to using them.
On Thu, Aug 24, 2023, at 2:39 PM, Jeremy Soller wrote:
> The System76 Thelio Io is a fan and power button LED controller. This
> driver fully supports the System76 Thelio Io, by exposing fan controls
> and sending the system suspend/resume state.
>
> Signed-off-by: Jeremy Soller <jeremy@xxxxxxxxxxxx>
> ---
> Documentation/hwmon/system76-thelio-io.rst | 31 ++
> MAINTAINERS | 7 +
> drivers/hwmon/Kconfig | 10 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/system76-thelio-io.c | 424 +++++++++++++++++++++
> 5 files changed, 473 insertions(+)
> create mode 100644 Documentation/hwmon/system76-thelio-io.rst
> create mode 100644 drivers/hwmon/system76-thelio-io.c
>
> diff --git a/Documentation/hwmon/system76-thelio-io.rst
> b/Documentation/hwmon/system76-thelio-io.rst
> new file mode 100644
> index 000000000000..7ca34bb47bbb
> --- /dev/null
> +++ b/Documentation/hwmon/system76-thelio-io.rst
> @@ -0,0 +1,31 @@
> +.. SPDX-License-Identifier: GPL-2.0-or-later
> +
> +Kernel driver system76-thelio-io
> +==========================
> +
> +Supported devices:
> +
> + * System76 Thelio Io (thelio_io_2)
> +
> +Author: Jeremy Soller
> +
> +Description
> +-----------
> +
> +This driver implements the sysfs interface for the System76 Thelio Io.
> +The System76 Thelio Io is a USB device with 4 fan connectors and a
> +power button LED.
> +
> +Usage Notes
> +-----------
> +
> +Since it is a USB device, hotswapping is possible. The device is
> autodetected.
> +
> +Sysfs entries
> +-------------
> +
> +=======================
> =====================================================================
> +fan[1-4]_input Connected fan rpm.
> +fan[1-4]_label Shows fan connector name.
> +pwm[1-4] Sets the fan speed. Values from 0-255.
> +=======================
> =====================================================================
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 48abe1a281f2..f4e8f7bdd1f5 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -20738,6 +20738,13 @@ L: platform-driver-x86@xxxxxxxxxxxxxxx
> S: Maintained
> F: drivers/platform/x86/system76_acpi.c
>
> +SYSTEM76 THELIO IO DRIVER
> +M: Jeremy Soller <jeremy@xxxxxxxxxxxx>
> +M: System76 <info@xxxxxxxxxxxx>
> +L: linux-hwmon@xxxxxxxxxxxxxxx
> +S: Maintained
> +F: drivers/hwmon/system76-thelio-io.c
> +
> SYSV FILESYSTEM
> S: Orphan
> F: Documentation/filesystems/sysv-fs.rst
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 307477b8a371..fdcf0baa2669 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1965,6 +1965,16 @@ config SENSORS_SMM665
> This driver can also be built as a module. If so, the module will
> be called smm665.
>
> +config SENSORS_SYSTEM76_THELIO_IO
> + tristate "System76 Thelio Io controller"
> + depends on HID
> + help
> + If you say yes here you get support for the System76 Thelio Io
> + controller.
> +
> + This driver can also be built as a module. If so, the module
> + will be called system76-thelio-io.
> +
> config SENSORS_ADC128D818
> tristate "Texas Instruments ADC128D818"
> depends on I2C
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 3f4b0fda0998..7cfdabb4e66f 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -199,6 +199,7 @@ obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
> obj-$(CONFIG_SENSORS_SPARX5) += sparx5-temp.o
> obj-$(CONFIG_SENSORS_STTS751) += stts751.o
> obj-$(CONFIG_SENSORS_SY7636A) += sy7636a-hwmon.o
> +obj-$(CONFIG_SENSORS_SYSTEM76_THELIO_IO) += system76-thelio-io.o
> obj-$(CONFIG_SENSORS_AMC6821) += amc6821.o
> obj-$(CONFIG_SENSORS_TC74) += tc74.o
> obj-$(CONFIG_SENSORS_THMC50) += thmc50.o
> diff --git a/drivers/hwmon/system76-thelio-io.c
> b/drivers/hwmon/system76-thelio-io.c
> new file mode 100644
> index 000000000000..4d9c2229cd3d
> --- /dev/null
> +++ b/drivers/hwmon/system76-thelio-io.c
> @@ -0,0 +1,424 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + *
> + * system76-thelio-io.c - Linux driver for System76 Thelio Io
> + * Copyright (C) 2023 System76
> + *
> + * Based on:
> + * corsair-cpro.c - Linux driver for Corsair Commander Pro
> + * Copyright (C) 2020 Marius Zachmann <mail@xxxxxxxxxxxxxxxxx>
> + *
> + * This driver uses hid reports to communicate with the device to
> allow hidraw userspace drivers
> + * still being used. The device does not use report ids. When using
> hidraw and this driver
> + * simultaniously, reports could be switched.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/completion.h>
> +#include <linux/hid.h>
> +#include <linux/hwmon.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/slab.h>
> +#include <linux/suspend.h>
> +#include <linux/types.h>
> +
> +#define BUFFER_SIZE 32
> +#define REQ_TIMEOUT 300
> +
> +#define HID_CMD 0
> +#define HID_RES 1
> +#define HID_DATA 2
> +
> +#define CMD_FAN_GET 7
> +#define CMD_FAN_SET 8
> +#define CMD_LED_SET_MODE 16
> +#define CMD_FAN_TACH 22
> +
> +struct thelio_io_device {
> + struct hid_device *hdev;
> + struct device *hwmon_dev;
> +#ifdef CONFIG_PM_SLEEP
> + struct notifier_block pm_notifier;
> +#endif
> + struct completion wait_input_report;
> + struct mutex mutex; /* whenever buffer is used, lock before
> send_usb_cmd */
> + u8 *buffer;
> +};
> +
> +/* converts response error in buffer to errno */
> +static int thelio_io_get_errno(struct thelio_io_device *thelio_io)
> +{
> + switch (thelio_io->buffer[HID_RES]) {
> + case 0x00: /* success */
> + return 0;
> + default:
> + return -EIO;
> + }
> +}
> +
> +/* send command, check for error in response, response in
> thelio_io->buffer */
> +static int send_usb_cmd(struct thelio_io_device *thelio_io, u8 command,
> + u8 byte1, u8 byte2, u8 byte3)
> +{
> + int ret;
> +
> + memset(thelio_io->buffer, 0x00, BUFFER_SIZE);
> + thelio_io->buffer[HID_CMD] = command;
> + thelio_io->buffer[HID_DATA] = byte1;
> + thelio_io->buffer[HID_DATA + 1] = byte2;
> + thelio_io->buffer[HID_DATA + 2] = byte3;
> +
> + reinit_completion(&thelio_io->wait_input_report);
> +
> + ret = hid_hw_output_report(thelio_io->hdev, thelio_io->buffer,
> BUFFER_SIZE);
> + if (ret < 0)
> + return ret;
> +
> + if (!wait_for_completion_timeout(&thelio_io->wait_input_report,
> + msecs_to_jiffies(REQ_TIMEOUT)))
> + return -ETIMEDOUT;
> +
> + return thelio_io_get_errno(thelio_io);
> +}
> +
> +static int thelio_io_raw_event(struct hid_device *hdev, struct
> hid_report *report,
> + u8 *data, int size)
> +{
> + struct thelio_io_device *thelio_io = hid_get_drvdata(hdev);
> +
> + /* only copy buffer when requested */
> + if (completion_done(&thelio_io->wait_input_report))
> + return 0;
> +
> + memcpy(thelio_io->buffer, data, min(BUFFER_SIZE, size));
> + complete(&thelio_io->wait_input_report);
> +
> + return 0;
> +}
> +
> +/* requests and returns single data values depending on channel */
> +static int get_data(struct thelio_io_device *thelio_io, int command,
> int channel,
> + bool two_byte_data)
> +{
> + int ret;
> +
> + mutex_lock(&thelio_io->mutex);
> +
> + ret = send_usb_cmd(thelio_io, command, channel, 0, 0);
> + if (ret)
> + goto out_unlock;
> +
> + ret = thelio_io->buffer[HID_DATA + 1];
> + if (two_byte_data)
> + ret |= thelio_io->buffer[HID_DATA + 2] << 8;
> +
> +out_unlock:
> + mutex_unlock(&thelio_io->mutex);
> + return ret;
> +}
> +
> +static int set_pwm(struct thelio_io_device *thelio_io, int channel,
> long val)
> +{
> + int ret;
> +
> + if (val < 0 || val > 255)
> + return -EINVAL;
> +
> + mutex_lock(&thelio_io->mutex);
> +
> + ret = send_usb_cmd(thelio_io, CMD_FAN_SET, channel, val, 0);
> +
> + mutex_unlock(&thelio_io->mutex);
> + return ret;
> +}
> +
> +static int thelio_io_read_string(struct device *dev, enum
> hwmon_sensor_types type,
> + u32 attr, int channel, const char **str)
> +{
> + switch (type) {
> + case hwmon_fan:
> + switch (attr) {
> + case hwmon_fan_label:
> + switch (channel) {
> + case 0:
> + *str = "CPU Fan";
> + return 0;
> + case 1:
> + *str = "Intake Fan";
> + return 0;
> + case 2:
> + *str = "GPU Fan";
> + return 0;
> + case 3:
> + *str = "Aux Fan";
> + return 0;
> + default:
> + break;
> + }
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int thelio_io_read(struct device *dev, enum hwmon_sensor_types
> type,
> + u32 attr, int channel, long *val)
> +{
> + struct thelio_io_device *thelio_io = dev_get_drvdata(dev);
> + int ret;
> +
> + switch (type) {
> + case hwmon_fan:
> + switch (attr) {
> + case hwmon_fan_input:
> + ret = get_data(thelio_io, CMD_FAN_TACH, channel, true);
> + if (ret < 0)
> + return ret;
> + *val = ret;
> + return 0;
> + default:
> + break;
> + }
> + break;
> + case hwmon_pwm:
> + switch (attr) {
> + case hwmon_pwm_input:
> + ret = get_data(thelio_io, CMD_FAN_GET, channel, false);
> + if (ret < 0)
> + return ret;
> + *val = ret;
> + return 0;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return -EOPNOTSUPP;
> +};
> +
> +static int thelio_io_write(struct device *dev, enum hwmon_sensor_types
> type,
> + u32 attr, int channel, long val)
> +{
> + struct thelio_io_device *thelio_io = dev_get_drvdata(dev);
> +
> + switch (type) {
> + case hwmon_pwm:
> + switch (attr) {
> + case hwmon_pwm_input:
> + return set_pwm(thelio_io, channel, val);
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return -EOPNOTSUPP;
> +};
> +
> +static umode_t thelio_io_is_visible(const void *data, enum
> hwmon_sensor_types type,
> + u32 attr, int channel)
> +{
> + switch (type) {
> + case hwmon_fan:
> + switch (attr) {
> + case hwmon_fan_input:
> + return 0444;
> + case hwmon_fan_label:
> + return 0444;
> + default:
> + break;
> + }
> + break;
> + case hwmon_pwm:
> + switch (attr) {
> + case hwmon_pwm_input:
> + return 0644;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return 0;
> +};
> +
> +static const struct hwmon_ops thelio_io_hwmon_ops = {
> + .is_visible = thelio_io_is_visible,
> + .read = thelio_io_read,
> + .read_string = thelio_io_read_string,
> + .write = thelio_io_write,
> +};
> +
> +static const struct hwmon_channel_info *thelio_io_info[] = {
> + HWMON_CHANNEL_INFO(chip,
> + HWMON_C_REGISTER_TZ),
> + HWMON_CHANNEL_INFO(fan,
> + HWMON_F_INPUT | HWMON_F_LABEL,
> + HWMON_F_INPUT | HWMON_F_LABEL,
> + HWMON_F_INPUT | HWMON_F_LABEL,
> + HWMON_F_INPUT | HWMON_F_LABEL
> + ),
> + HWMON_CHANNEL_INFO(pwm,
> + HWMON_PWM_INPUT,
> + HWMON_PWM_INPUT,
> + HWMON_PWM_INPUT,
> + HWMON_PWM_INPUT
> + ),
> + NULL
> +};
> +
> +static const struct hwmon_chip_info thelio_io_chip_info = {
> + .ops = &thelio_io_hwmon_ops,
> + .info = thelio_io_info,
> +};
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int thelio_io_pm(struct notifier_block *nb, unsigned long
> action, void *data)
> +{
> + struct thelio_io_device *thelio_io = container_of(nb, struct
> thelio_io_device, pm_notifier);
> +
> + switch (action) {
> + case PM_HIBERNATION_PREPARE:
> + case PM_SUSPEND_PREPARE:
> + mutex_lock(&thelio_io->mutex);
> + send_usb_cmd(thelio_io, CMD_LED_SET_MODE, 0, 1, 0);
> + mutex_unlock(&thelio_io->mutex);
> + break;
> +
> + case PM_POST_HIBERNATION:
> + case PM_POST_SUSPEND:
> + mutex_lock(&thelio_io->mutex);
> + send_usb_cmd(thelio_io, CMD_LED_SET_MODE, 0, 0, 0);
> + mutex_unlock(&thelio_io->mutex);
> + break;
> +
> + case PM_POST_RESTORE:
> + case PM_RESTORE_PREPARE:
> + default:
> + break;
> + }
> +
> + return NOTIFY_DONE;
> +}
> +#endif
> +
> +static int thelio_io_probe(struct hid_device *hdev, const struct
> hid_device_id *id)
> +{
> + struct thelio_io_device *thelio_io;
> + int ret;
> +
> + thelio_io = devm_kzalloc(&hdev->dev, sizeof(*thelio_io), GFP_KERNEL);
> + if (!thelio_io)
> + return -ENOMEM;
> +
> + thelio_io->buffer = devm_kmalloc(&hdev->dev, BUFFER_SIZE, GFP_KERNEL);
> + if (!thelio_io->buffer)
> + return -ENOMEM;
> +
> + ret = hid_parse(hdev);
> + if (ret)
> + return ret;
> +
> + ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
> + if (ret)
> + return ret;
> +
> + ret = hid_hw_open(hdev);
> + if (ret)
> + goto out_hw_stop;
> +
> + thelio_io->hdev = hdev;
> + hid_set_drvdata(hdev, thelio_io);
> + mutex_init(&thelio_io->mutex);
> + init_completion(&thelio_io->wait_input_report);
> +
> + hid_device_io_start(hdev);
> +
> + if (hdev->maxcollection == 1 && hdev->collection[0].usage ==
> 0xFF600061) {
> + thelio_io->hwmon_dev = hwmon_device_register_with_info(&hdev->dev,
> + "system76_thelio_io",
> + thelio_io,
> + &thelio_io_chip_info,
> + 0);
> + if (IS_ERR(thelio_io->hwmon_dev)) {
> + ret = PTR_ERR(thelio_io->hwmon_dev);
> + goto out_hw_close;
> + }
> +
> + #ifdef CONFIG_PM_SLEEP
> + thelio_io->pm_notifier.notifier_call = thelio_io_pm;
> + register_pm_notifier(&thelio_io->pm_notifier);
> + #endif
> + }
> +
> + return 0;
> +
> +out_hw_close:
> + hid_hw_close(hdev);
> +out_hw_stop:
> + hid_hw_stop(hdev);
> + return ret;
> +}
> +
> +static void thelio_io_remove(struct hid_device *hdev)
> +{
> + struct thelio_io_device *thelio_io = hid_get_drvdata(hdev);
> +
> + if (thelio_io->hwmon_dev) {
> + hwmon_device_unregister(thelio_io->hwmon_dev);
> +
> + #ifdef CONFIG_PM_SLEEP
> + unregister_pm_notifier(&thelio_io->pm_notifier);
> + #endif
> + }
> +
> + hid_hw_close(hdev);
> + hid_hw_stop(hdev);
> +}
> +
> +static const struct hid_device_id thelio_io_devices[] = {
> + { HID_USB_DEVICE(0x3384, 0x000B) }, /* thelio_io_2 */
> + { }
> +};
> +
> +static struct hid_driver thelio_io_driver = {
> + .name = "system76-thelio-io",
> + .id_table = thelio_io_devices,
> + .probe = thelio_io_probe,
> + .remove = thelio_io_remove,
> + .raw_event = thelio_io_raw_event,
> +};
> +
> +MODULE_DEVICE_TABLE(hid, thelio_io_devices);
> +MODULE_LICENSE("GPL");
> +
> +static int __init thelio_io_init(void)
> +{
> + return hid_register_driver(&thelio_io_driver);
> +}
> +
> +static void __exit thelio_io_exit(void)
> +{
> + hid_unregister_driver(&thelio_io_driver);
> +}
> +
> +/*
> + * When compiling this driver as built-in, hwmon initcalls will get
> called before the
> + * hid driver and this driver would fail to register. late_initcall
> solves this.
> + */
> +late_initcall(thelio_io_init);
> +module_exit(thelio_io_exit);
> --
> 2.34.1
