Re: [PATCH v4 06/13] platform/x86: oxpec: Add charge threshold and behaviour to OneXPlayer

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 11-Mar-25 17:53, Antheas Kapenekakis wrote:
> With the X1 (AMD), OneXPlayer added a charge limit and charge bypass to
> their devices. Charge limit allows for choosing an arbitrary battery
> charge setpoint in percentages. Charge bypass allows to instruct the
> device to stop charging either when it is in s0 or always.

Again please don't use the word bypass, use inhibit instead.

> This feature was then extended for the F1Pro as well. OneXPlayer also
> released BIOS updates for the X1 Mini, X1 (Intel), and F1 devices that
> add support for this feature. Therefore, enable it for all F1 and
> X1 devices.
> 
> Add both of these under the standard sysfs battery endpoints for them,
> by looking for the battery. OneXPlayer devices have a single battery.
> 
> Signed-off-by: Antheas Kapenekakis <lkml@antheas.dev>
> ---
>  drivers/platform/x86/Kconfig |   1 +
>  drivers/platform/x86/oxpec.c | 217 +++++++++++++++++++++++++++++++++++
>  2 files changed, 218 insertions(+)
> 
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 82cfc76bc5c9..f4d993658c01 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -1189,6 +1189,7 @@ config SEL3350_PLATFORM
>  config OXP_EC
>  	tristate "OneXPlayer EC platform control"
>  	depends on ACPI_EC
> +	depends on ACPI_BATTERY
>  	depends on HWMON
>  	depends on X86
>  	help
> diff --git a/drivers/platform/x86/oxpec.c b/drivers/platform/x86/oxpec.c
> index dc3a0871809c..d73a10598d8f 100644
> --- a/drivers/platform/x86/oxpec.c
> +++ b/drivers/platform/x86/oxpec.c
> @@ -24,6 +24,7 @@
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>  #include <linux/processor.h>
> +#include <acpi/battery.h>
>  
>  /* Handle ACPI lock mechanism */
>  static u32 oxp_mutex;
> @@ -87,6 +88,24 @@ static enum oxp_board board;
>  
>  #define OXP_TURBO_RETURN_VAL           0x00 /* Common return val */
>  
> +/* Battery bypass settings */
> +#define EC_CHARGE_CONTROL_BEHAVIOURS_X1	(BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO)             | \
> +					 BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE)    | \
> +					 BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE_S0))
> +
> +#define OXP_X1_CHARGE_LIMIT_REG      0xA3 /* X1 charge limit (%) */
> +#define OXP_X1_CHARGE_BYPASS_REG     0xA4 /* X1 bypass charging */
> +
> +#define OXP_X1_CHARGE_BYPASS_MASK_S0 0x01

Again avoid the word BYPASS please, if OneXPlayer are calling this bypass in their 
own documentation maybe add a note here when defining the registers that OneXPlayer
calls this bypass and then use inhibit from there on.

> +/*
> + * Cannot control S3, S5 individually.
> + * X1 Mask is 0x0A, OneXFly F1Pro is just 0x02
> + * but the extra bit on the X1 does nothing.
> + */
> +#define OXP_X1_CHARGE_BYPASS_MASK_S3S5 0x02

Ok, so suspend is treated as off, but that is for S3 suspend, what about
s2idle, or does this hw not do s2idle ?

> +#define OXP_X1_CHARGE_BYPASS_MASK_ALWAYS (OXP_X1_CHARGE_BYPASS_MASK_S0 | \
> +	OXP_X1_CHARGE_BYPASS_MASK_S3S5)
> +
>  static const struct dmi_system_id dmi_table[] = {
>  	{
>  		.matches = {
> @@ -434,6 +453,194 @@ static ssize_t tt_toggle_show(struct device *dev,
>  
>  static DEVICE_ATTR_RW(tt_toggle);
>  
> +/* Callbacks for charge behaviour attributes */
> +static bool charge_behaviour_supported(void)
> +{
> +	switch (board) {
> +	case oxp_x1:
> +	case oxp_fly:
> +		return 1;
> +	default:
> +		break;
> +	}
> +	return 0;
> +}
> +
> +static ssize_t charge_behaviour_store(struct device *dev,
> +			       struct device_attribute *attr, const char *buf,
> +			       size_t count)
> +{
> +	unsigned int available;
> +	long val, s0, always;
> +	int ret;
> +	u8 reg;
> +
> +	switch (board) {
> +	case oxp_x1:
> +	case oxp_fly:
> +		s0 = OXP_X1_CHARGE_BYPASS_MASK_S0;
> +		always = OXP_X1_CHARGE_BYPASS_MASK_ALWAYS;
> +		reg = OXP_X1_CHARGE_BYPASS_REG;
> +		available = EC_CHARGE_CONTROL_BEHAVIOURS_X1;
> +		break;

Since these are always the same this does not seem useful, please
use the defines directly below.

> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = power_supply_charge_behaviour_parse(available, buf);
> +	if (ret < 0)
> +		return ret;
> +
> +	switch (ret) {
> +	case POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO:
> +		val = 0;
> +		break;
> +	case POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE_S0:
> +		val = s0;
> +		break;
> +	case POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE:
> +		val = always;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = write_to_ec(reg, val);
> +	if (ret)
> +		return ret;
> +
> +	return count;
> +}
> +
> +static ssize_t charge_behaviour_show(struct device *dev,
> +			      struct device_attribute *attr, char *buf)
> +{
> +	long val, s0, always, sel;
> +	unsigned int available;
> +	int ret;
> +	u8 reg;
> +
> +	switch (board) {
> +	case oxp_x1:
> +	case oxp_fly:
> +		s0 = OXP_X1_CHARGE_BYPASS_MASK_S0;
> +		always = OXP_X1_CHARGE_BYPASS_MASK_ALWAYS;
> +		reg = OXP_X1_CHARGE_BYPASS_REG;
> +		available = EC_CHARGE_CONTROL_BEHAVIOURS_X1;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = read_from_ec(reg, 1, &val);
> +	if (ret)
> +		return ret;
> +
> +	if ((val & always) == always)
> +		sel = POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE;
> +	else if ((val & s0) == s0)
> +		sel = POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE_S0;
> +	else
> +		sel = POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO;
> +
> +	return power_supply_charge_behaviour_show(dev, available, sel, buf);
> +}
> +
> +static DEVICE_ATTR_RW(charge_behaviour);
> +
> +static ssize_t charge_control_end_threshold_store(struct device *dev,
> +			       struct device_attribute *attr, const char *buf,
> +			       size_t count)
> +{
> +	u64 val, reg;
> +	int ret;
> +
> +	ret = kstrtou64(buf, 10, &val);
> +	if (ret)
> +		return ret;
> +
> +	if (val > 100)
> +		return -EINVAL;
> +
> +	switch (board) {
> +	case oxp_x1:
> +	case oxp_fly:
> +		reg = OXP_X1_CHARGE_LIMIT_REG;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = write_to_ec(reg, val);
> +	if (ret)
> +		return ret;
> +
> +	return count;
> +}
> +
> +static ssize_t charge_control_end_threshold_show(struct device *dev,
> +			      struct device_attribute *attr, char *buf)
> +{
> +	long val;
> +	int ret;
> +	u8 reg;
> +
> +	switch (board) {
> +	case oxp_x1:
> +	case oxp_fly:
> +		reg = OXP_X1_CHARGE_LIMIT_REG;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = read_from_ec(reg, 1, &val);
> +	if (ret)
> +		return ret;
> +
> +	return sysfs_emit(buf, "%ld\n", val);
> +}
> +
> +static DEVICE_ATTR_RW(charge_control_end_threshold);
> +
> +static int oxp_battery_add(struct power_supply *battery, struct acpi_battery_hook *hook)
> +{
> +	/* OneXPlayer devices only have one battery. */
> +	if (strcmp(battery->desc->name, "BAT0") != 0 &&
> +	    strcmp(battery->desc->name, "BAT1") != 0 &&
> +	    strcmp(battery->desc->name, "BATC") != 0 &&
> +	    strcmp(battery->desc->name, "BATT") != 0)
> +		return -ENODEV;
> +
> +	if (device_create_file(&battery->dev,
> +	    &dev_attr_charge_control_end_threshold))
> +		return -ENODEV;
> +
> +	if (device_create_file(&battery->dev,
> +	    &dev_attr_charge_behaviour)) {
> +		device_remove_file(&battery->dev,
> +				&dev_attr_charge_control_end_threshold);
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int oxp_battery_remove(struct power_supply *battery, struct acpi_battery_hook *hook)
> +{
> +	device_remove_file(&battery->dev,
> +			   &dev_attr_charge_control_end_threshold);
> +	device_remove_file(&battery->dev,
> +			   &dev_attr_charge_behaviour);
> +	return 0;
> +}
> +
> +static struct acpi_battery_hook battery_hook = {
> +	.add_battery = oxp_battery_add,
> +	.remove_battery = oxp_battery_remove,
> +	.name = "OneXPlayer Battery",
> +};
> +

Since this is new code it should use the new power-supply extension support instead
of the old battery_hook mechanism:

https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6037802bbae892f3ad0c7b4c4faee39b967e32b0



>  /* PWM enable/disable functions */
>  static int oxp_pwm_enable(void)
>  {
> @@ -716,15 +923,25 @@ static int oxp_platform_probe(struct platform_device *pdev)
>  	hwdev = devm_hwmon_device_register_with_info(dev, "oxpec", NULL,
>  						     &oxp_ec_chip_info, NULL);
>  
> +	if (charge_behaviour_supported())
> +		battery_hook_register(&battery_hook);
> +
>  	return PTR_ERR_OR_ZERO(hwdev);
>  }
>  
> +static void oxp_platform_remove(struct platform_device *device)
> +{
> +	if (charge_behaviour_supported())
> +		battery_hook_unregister(&battery_hook);
> +}
> +
>  static struct platform_driver oxp_platform_driver = {
>  	.driver = {
>  		.name = "oxp-platform",
>  		.dev_groups = oxp_ec_groups,
>  	},
>  	.probe = oxp_platform_probe,
> +	.remove = oxp_platform_remove,
>  };
>  
>  static struct platform_device *oxp_platform_device;

Regards,

Hans