[PATCH v2 08/16] samsung-laptop: add battery life extender support

From: Corentin Chary
Date: Sat Nov 26 2011 - 05:02:59 EST


Signed-off-by: Corentin Chary <corentincj@xxxxxxxxxx>
Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
.../ABI/testing/sysfs-driver-samsung-laptop | 10 +++
drivers/platform/x86/samsung-laptop.c | 82 ++++++++++++++++++++
2 files changed, 92 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-driver-samsung-laptop b/Documentation/ABI/testing/sysfs-driver-samsung-laptop
index 0a81023..a6a56e1 100644
--- a/Documentation/ABI/testing/sysfs-driver-samsung-laptop
+++ b/Documentation/ABI/testing/sysfs-driver-samsung-laptop
@@ -17,3 +17,13 @@ Description: Some Samsung laptops have different "performance levels"
Specifically, not all support the "overclock" option,
and it's still unknown if this value even changes
anything, other than making the user feel a bit better.
+
+What: /sys/devices/platform/samsung/battery_life_extender
+Date: December 1, 2011
+KernelVersion: 3.3
+Contact: Corentin Chary <corentin.chary@xxxxxxxxx>
+Description: Max battery charge level can be modified, battery cycle
+ life can be extended by reducing the max battery charge
+ level.
+ 0 means normal battery mode (100% charge)
+ 1 means battery life extender mode (80% charge)
diff --git a/drivers/platform/x86/samsung-laptop.c b/drivers/platform/x86/samsung-laptop.c
index 638b368..74c34ce 100644
--- a/drivers/platform/x86/samsung-laptop.c
+++ b/drivers/platform/x86/samsung-laptop.c
@@ -104,6 +104,10 @@ struct sabi_commands {
u16 get_performance_level;
u16 set_performance_level;

+ /* 0x80 is off, 0x81 is on */
+ u16 get_battery_life_extender;
+ u16 set_battery_life_extender;
+
/*
* Tell the BIOS that Linux is running on this machine.
* 81 is on, 80 is off
@@ -157,6 +161,9 @@ static const struct sabi_config sabi_configs[] = {
.get_performance_level = 0x08,
.set_performance_level = 0x09,

+ .get_battery_life_extender = 0xFFFF,
+ .set_battery_life_extender = 0xFFFF,
+
.set_linux = 0x0a,
},

@@ -204,6 +211,9 @@ static const struct sabi_config sabi_configs[] = {
.get_performance_level = 0x31,
.set_performance_level = 0x32,

+ .get_battery_life_extender = 0x65,
+ .set_battery_life_extender = 0x66,
+
.set_linux = 0xff,
},

@@ -543,8 +553,78 @@ static ssize_t set_performance_level(struct device *dev,
static DEVICE_ATTR(performance_level, S_IWUSR | S_IRUGO,
get_performance_level, set_performance_level);

+static int read_battery_life_extender(struct samsung_laptop *samsung)
+{
+ const struct sabi_commands *commands = &samsung->config->commands;
+ struct sabi_data data;
+ int retval;
+
+ if (commands->get_battery_life_extender == 0xFFFF)
+ return -ENODEV;
+
+ memset(&data, 0, sizeof(data));
+ data.data[0] = 0x80;
+ retval = sabi_command(samsung, commands->get_battery_life_extender,
+ &data, &data);
+
+ if (retval)
+ return retval;
+
+ if (data.data[0] != 0 && data.data[0] != 1)
+ return -ENODEV;
+
+ return data.data[0];
+}
+
+static int write_battery_life_extender(struct samsung_laptop *samsung,
+ int enabled)
+{
+ const struct sabi_commands *commands = &samsung->config->commands;
+ struct sabi_data data;
+
+ memset(&data, 0, sizeof(data));
+ data.data[0] = 0x80 | enabled;
+ return sabi_command(samsung, commands->set_battery_life_extender,
+ &data, NULL);
+}
+
+static ssize_t get_battery_life_extender(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct samsung_laptop *samsung = dev_get_drvdata(dev);
+ int ret;
+
+ ret = read_battery_life_extender(samsung);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", ret);
+}
+
+static ssize_t set_battery_life_extender(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct samsung_laptop *samsung = dev_get_drvdata(dev);
+ int ret, value;
+
+ if (!count || sscanf(buf, "%i", &value) != 1)
+ return -EINVAL;
+
+ ret = write_battery_life_extender(samsung, !!value);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static DEVICE_ATTR(battery_life_extender, S_IWUSR | S_IRUGO,
+ get_battery_life_extender, set_battery_life_extender);
+
static struct attribute *platform_attributes[] = {
&dev_attr_performance_level.attr,
+ &dev_attr_battery_life_extender.attr,
NULL
};

@@ -643,6 +723,8 @@ static mode_t samsung_sysfs_is_visible(struct kobject *kobj,

if (attr == &dev_attr_performance_level.attr)
ok = !!samsung->config->performance_levels[0].name;
+ if (attr == &dev_attr_battery_life_extender.attr)
+ ok = !!(read_battery_life_extender(samsung) >= 0);

return ok ? attr->mode : 0;
}
--
1.7.5.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/