Re: [GIT PULL RFC] directly poll battery strength when reading power_supply

[Jeremy Fitzhardinge <jeremy@goop.org>]

On 12/07/2011 04:51 AM, Richard Hughes wrote:
> On 6 December 2011 17:10, Jeremy Fitzhardinge <jeremy@goop.org> wrote:
>> Something like  HID UPS would appear to be in the middle of the USB
>> devices, but actually powers the whole machine (or more).
> Right, although I think we still need an explicit
> "is_powering_computer" flag or something exposed to userspace
> ortherwise we're back to heuristics and hand coded quirks.

Something like this?

diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
index e15d4c9..21178eb 100644
--- a/drivers/power/power_supply_sysfs.c
+++ b/drivers/power/power_supply_sysfs.c
@@ -63,6 +63,9 @@ static ssize_t power_supply_show_property(struct device *dev,
 	static char *capacity_level_text[] = {
 		"Unknown", "Critical", "Low", "Normal", "High", "Full"
 	};
+	static char *scope_text[] = {
+		"Unknown", "System", "Device"
+	};
 	ssize_t ret = 0;
 	struct power_supply *psy = dev_get_drvdata(dev);
 	const ptrdiff_t off = attr - power_supply_attrs;
@@ -95,6 +98,8 @@ static ssize_t power_supply_show_property(struct device *dev,
 		return sprintf(buf, "%s\n", capacity_level_text[value.intval]);
 	else if (off == POWER_SUPPLY_PROP_TYPE)
 		return sprintf(buf, "%s\n", type_text[value.intval]);
+	else if (off == POWER_SUPPLY_PROP_SCOPE)
+		return sprintf(buf, "%s\n", scope_text[value.intval]);
 	else if (off >= POWER_SUPPLY_PROP_MODEL_NAME)
 		return sprintf(buf, "%s\n", value.strval);
 
@@ -167,6 +172,7 @@ static struct device_attribute power_supply_attrs[] = {
 	POWER_SUPPLY_ATTR(time_to_full_now),
 	POWER_SUPPLY_ATTR(time_to_full_avg),
 	POWER_SUPPLY_ATTR(type),
+	POWER_SUPPLY_ATTR(scope),
 	/* Properties of type `const char *' */
 	POWER_SUPPLY_ATTR(model_name),
 	POWER_SUPPLY_ATTR(manufacturer),
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index a28f2df..2e3c827 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -74,6 +74,12 @@ enum {
 	POWER_SUPPLY_CAPACITY_LEVEL_FULL,
 };
 
+enum {
+	POWER_SUPPLY_SCOPE_UNKNOWN = 0,
+	POWER_SUPPLY_SCOPE_SYSTEM,
+	POWER_SUPPLY_SCOPE_DEVICE,
+};
+
 enum power_supply_property {
 	/* Properties of type `int' */
 	POWER_SUPPLY_PROP_STATUS = 0,
@@ -116,6 +122,7 @@ enum power_supply_property {
 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
 	POWER_SUPPLY_PROP_TYPE, /* use power_supply.type instead */
+	POWER_SUPPLY_PROP_SCOPE,
 	/* Properties of type `const char *' */
 	POWER_SUPPLY_PROP_MODEL_NAME,
 	POWER_SUPPLY_PROP_MANUFACTURER,


>> And if the device being pointed to is a mouse, then upower knows its
>> powering a mouse.
> Define "mouse" -- an input devices with two axis? I think an explicit
> type might be clearer.

Well, what are you really trying to represent?  Is it enough for upower
to say "here are some devices with batteries, this is everything I know
about them", and let its clients work out what they really are?  Does
upower need to work out what kind of device it is?

Thanks,
    J