From 668ce99e4ed4c07bb14465f80492bc6cf76ed3c9 Mon Sep 17 00:00:00 2001 From: Srinivas Pandruvada Date: Thu, 21 May 2020 13:30:15 -0700 Subject: ACPI: DPTF: Additional sysfs attributes for power participant driver MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add two additional attributes to the existing power participant driver: rest_of_platform_power_mw: (RO) Shows the rest of worst case platform power in mW outside of S0C. This will help in power distribution to SoC and rest of the system. For example on a test system, this value is 2.5W with a 15W TDP SoC. Based on the adapter rating (adapter_rating_mw), user space software can decide on proper power allocation to SoC to improve short term performance via powercap/RAPL interface. prochot_confirm: (WO) Confirm EC about a prochot notification. Also userspace is notified via sysfs_notify(), whenever power source or rest of the platform power is changed. So user space can use poll() system call on those attributes. The ACPI methods used in this patch are as follows: PROP This object evaluates to the rest of worst case platform power in mW. Bits: 23:0 Worst case rest of platform power in mW. PBOK PBOK is a method designed to provide a mechanism for OSPM to change power setting before EC can de-assert a PROCHOT from a device. The EC may receive several PROCHOTs, so it has a sequence number attached to PSRC (read via existing attribute "platform_power_source"). Once OSPM takes action for a PSRC change notification, it can call PBOK method to confirm with the sequence number. Bits: 3:0 Power Delivery State Change Sequence number 30 Reserved 31 0 – Not OK to de-assert PROCHOT 1 – OK to de-assert PROCHOT PSRC (Platform Power Source): Not new in this patch but for documentation for new bits This object evaluates to an integer that represents the system power source as well as the power delivery state change sequence number. Bits: 3:0 The current power source as an integer for AC, DC, USB, Wireless. 0 = DC, 1 = AC, 2 = USB, 3 = Wireless Charging 7:4 Power Delivery State Change Sequence Number. Default value is 0 Notifications: 0x81: (Power State Change) Used to notify when the power source has changed. 0x84: (PROP change) Used to notify when the platform rest of power has changed. Signed-off-by: Srinivas Pandruvada [ rjw: Subject, minor ABI documentation edit ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/dptf/dptf_power.c | 69 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 68 insertions(+), 1 deletion(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/dptf/dptf_power.c b/drivers/acpi/dptf/dptf_power.c index e4e8b75d39f0..abe99039af74 100644 --- a/drivers/acpi/dptf/dptf_power.c +++ b/drivers/acpi/dptf/dptf_power.c @@ -16,6 +16,7 @@ * ARTG : Adapter rating * CTYP : Charger type * PBSS : Battery steady power + * PROP : Rest of worst case platform Power */ #define DPTF_POWER_SHOW(name, object) \ static ssize_t name##_show(struct device *dev,\ @@ -39,12 +40,34 @@ DPTF_POWER_SHOW(platform_power_source, PSRC) DPTF_POWER_SHOW(adapter_rating_mw, ARTG) DPTF_POWER_SHOW(battery_steady_power_mw, PBSS) DPTF_POWER_SHOW(charger_type, CTYP) +DPTF_POWER_SHOW(rest_of_platform_power_mw, PROP) static DEVICE_ATTR_RO(max_platform_power_mw); static DEVICE_ATTR_RO(platform_power_source); static DEVICE_ATTR_RO(adapter_rating_mw); static DEVICE_ATTR_RO(battery_steady_power_mw); static DEVICE_ATTR_RO(charger_type); +static DEVICE_ATTR_RO(rest_of_platform_power_mw); + +static ssize_t prochot_confirm_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct acpi_device *acpi_dev = dev_get_drvdata(dev); + acpi_status status; + int seq_no; + + if (kstrtouint(buf, 0, &seq_no) < 0) + return -EINVAL; + + status = acpi_execute_simple_method(acpi_dev->handle, "PBOK", seq_no); + if (ACPI_SUCCESS(status)) + return count; + + return -EINVAL; +} + +static DEVICE_ATTR_WO(prochot_confirm); static struct attribute *dptf_power_attrs[] = { &dev_attr_max_platform_power_mw.attr, @@ -52,6 +75,8 @@ static struct attribute *dptf_power_attrs[] = { &dev_attr_adapter_rating_mw.attr, &dev_attr_battery_steady_power_mw.attr, &dev_attr_charger_type.attr, + &dev_attr_rest_of_platform_power_mw.attr, + &dev_attr_prochot_confirm.attr, NULL }; @@ -60,6 +85,33 @@ static const struct attribute_group dptf_power_attribute_group = { .name = "dptf_power" }; +#define POWER_STATE_CHANGED 0x81 +#define POWER_PROP_CHANGE_EVENT 0x84 + +static void dptf_power_notify(acpi_handle handle, u32 event, void *data) +{ + struct platform_device *pdev = data; + char *attr; + + switch (event) { + case POWER_STATE_CHANGED: + attr = "platform_power_source"; + break; + case POWER_PROP_CHANGE_EVENT: + attr = "rest_of_platform_power_mw"; + break; + default: + dev_err(&pdev->dev, "Unsupported event [0x%x]\n", event); + return; + } + + /* + * Notify that an attribute is changed, so that user space can read + * again. + */ + sysfs_notify(&pdev->dev.kobj, "dptf_power", attr); +} + static int dptf_power_add(struct platform_device *pdev) { struct acpi_device *acpi_dev; @@ -78,10 +130,21 @@ static int dptf_power_add(struct platform_device *pdev) if (ptype != 0x11) return -ENODEV; + result = acpi_install_notify_handler(acpi_dev->handle, + ACPI_DEVICE_NOTIFY, + dptf_power_notify, + (void *)pdev); + if (result) + return result; + result = sysfs_create_group(&pdev->dev.kobj, &dptf_power_attribute_group); - if (result) + if (result) { + acpi_remove_notify_handler(acpi_dev->handle, + ACPI_DEVICE_NOTIFY, + dptf_power_notify); return result; + } platform_set_drvdata(pdev, acpi_dev); @@ -90,7 +153,11 @@ static int dptf_power_add(struct platform_device *pdev) static int dptf_power_remove(struct platform_device *pdev) { + struct acpi_device *acpi_dev = platform_get_drvdata(pdev); + acpi_remove_notify_handler(acpi_dev->handle, + ACPI_DEVICE_NOTIFY, + dptf_power_notify); sysfs_remove_group(&pdev->dev.kobj, &dptf_power_attribute_group); return 0; -- cgit v1.2.3