toshiba_acpi: Add support for USB Sleep and Charge function

Newer Toshiba models now come with a feature called Sleep and Charge,
where the computer USB ports remain powered when the computer is
asleep or turned off.

This patch adds support to such feature, creating a sysfs entry
called "usb_sleep_charge" to set the desired charging mode or to
disable it.

The sysfs entry accepts three parameters, 0, 1 and 2, beign disabled,
alternate and auto respectively.

The auto mode stands for USB conformant devices (which most are), and
the alternate mode stands for those non USB conformant devices that
require more power.

Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

drivers/platform/x86/toshiba_acpi.c

@@ -122,6 +122,7 @@ MODULE_LICENSE("GPL");
 #define HCI_ECO_MODE			0x0097
 #define HCI_ACCELEROMETER2		0x00a6
 #define SCI_ILLUMINATION		0x014e
+#define SCI_USB_SLEEP_CHARGE		0x0150
 #define SCI_KBD_ILLUM_STATUS		0x015c
 #define SCI_TOUCHPAD			0x050e
 
@@ -146,6 +147,10 @@ MODULE_LICENSE("GPL");
 #define SCI_KBD_MODE_ON			0x8
 #define SCI_KBD_MODE_OFF		0x10
 #define SCI_KBD_TIME_MAX		0x3c001a
+#define SCI_USB_CHARGE_MODE_MASK	0xff
+#define SCI_USB_CHARGE_DISABLED		0x30000
+#define SCI_USB_CHARGE_ALTERNATE	0x30009
+#define SCI_USB_CHARGE_AUTO		0x30021
 
 struct toshiba_acpi_dev {
 	struct acpi_device *acpi_dev;
@@ -177,6 +182,7 @@ struct toshiba_acpi_dev {
 	unsigned int touchpad_supported:1;
 	unsigned int eco_supported:1;
 	unsigned int accelerometer_supported:1;
+	unsigned int usb_sleep_charge_supported:1;
 	unsigned int sysfs_created:1;
 
 	struct mutex mutex;
@@ -760,6 +766,53 @@ static int toshiba_accelerometer_get(struct toshiba_acpi_dev *dev,
 	return 0;
 }
 
+/* Sleep (Charge and Music) utilities support */
+static int toshiba_usb_sleep_charge_get(struct toshiba_acpi_dev *dev,
+					u32 *mode)
+{
+	u32 result;
+
+	if (!sci_open(dev))
+		return -EIO;
+
+	result = sci_read(dev, SCI_USB_SLEEP_CHARGE, mode);
+	sci_close(dev);
+	if (result == TOS_FAILURE) {
+		pr_err("ACPI call to set USB S&C mode failed\n");
+		return -EIO;
+	} else if (result == TOS_NOT_SUPPORTED) {
+		pr_info("USB Sleep and Charge not supported\n");
+		return -ENODEV;
+	} else if (result == TOS_INPUT_DATA_ERROR) {
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int toshiba_usb_sleep_charge_set(struct toshiba_acpi_dev *dev,
+					u32 mode)
+{
+	u32 result;
+
+	if (!sci_open(dev))
+		return -EIO;
+
+	result = sci_write(dev, SCI_USB_SLEEP_CHARGE, mode);
+	sci_close(dev);
+	if (result == TOS_FAILURE) {
+		pr_err("ACPI call to set USB S&C mode failed\n");
+		return -EIO;
+	} else if (result == TOS_NOT_SUPPORTED) {
+		pr_info("USB Sleep and Charge not supported\n");
+		return -ENODEV;
+	} else if (result == TOS_INPUT_DATA_ERROR) {
+		return -EIO;
+	}
+
+	return 0;
+}
+
 /* Bluetooth rfkill handlers */
 
 static u32 hci_get_bt_present(struct toshiba_acpi_dev *dev, bool *present)
@@ -1313,6 +1366,12 @@ static ssize_t toshiba_touchpad_show(struct device *dev,
 static ssize_t toshiba_position_show(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf);
+static ssize_t toshiba_usb_sleep_charge_show(struct device *dev,
+					     struct device_attribute *attr,
+					     char *buf);
+static ssize_t toshiba_usb_sleep_charge_store(struct device *dev,
+					      struct device_attribute *attr,
+					      const char *buf, size_t count);
 
 static DEVICE_ATTR(kbd_backlight_mode, S_IRUGO | S_IWUSR,
 		   toshiba_kbd_bl_mode_show, toshiba_kbd_bl_mode_store);
@@ -1324,6 +1383,9 @@ static DEVICE_ATTR(kbd_backlight_timeout, S_IRUGO | S_IWUSR,
 static DEVICE_ATTR(touchpad, S_IRUGO | S_IWUSR,
 		   toshiba_touchpad_show, toshiba_touchpad_store);
 static DEVICE_ATTR(position, S_IRUGO, toshiba_position_show, NULL);
+static DEVICE_ATTR(usb_sleep_charge, S_IRUGO | S_IWUSR,
+		   toshiba_usb_sleep_charge_show,
+		   toshiba_usb_sleep_charge_store);
 
 static struct attribute *toshiba_attributes[] = {
 	&dev_attr_kbd_backlight_mode.attr,
@@ -1332,6 +1394,7 @@ static struct attribute *toshiba_attributes[] = {
 	&dev_attr_kbd_backlight_timeout.attr,
 	&dev_attr_touchpad.attr,
 	&dev_attr_position.attr,
+	&dev_attr_usb_sleep_charge.attr,
 	NULL,
 };
 
@@ -1549,6 +1612,56 @@ static ssize_t toshiba_position_show(struct device *dev,
 	return sprintf(buf, "%d %d %d\n", x, y, z);
 }
 
+static ssize_t toshiba_usb_sleep_charge_show(struct device *dev,
+					     struct device_attribute *attr,
+					     char *buf)
+{
+	struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
+	u32 mode;
+	int ret;
+
+	ret = toshiba_usb_sleep_charge_get(toshiba, &mode);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%x\n", mode & SCI_USB_CHARGE_MODE_MASK);
+}
+
+static ssize_t toshiba_usb_sleep_charge_store(struct device *dev,
+					      struct device_attribute *attr,
+					      const char *buf, size_t count)
+{
+	struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
+	u32 mode;
+	int state;
+	int ret;
+
+	ret = kstrtoint(buf, 0, &state);
+	if (ret)
+		return ret;
+	/* Check for supported values, where:
+	 * 0 - Disabled
+	 * 1 - Alternate (Non USB conformant devices that require more power)
+	 * 2 - Auto (USB conformant devices)
+	 */
+	if (state != 0 && state != 1 && state != 2)
+		return -EINVAL;
+
+	/* Set the USB charging mode to internal value */
+	if (state == 0)
+		mode = SCI_USB_CHARGE_DISABLED;
+	else if (state == 1)
+		mode = SCI_USB_CHARGE_ALTERNATE;
+	else if (state == 2)
+		mode = SCI_USB_CHARGE_AUTO;
+
+	ret = toshiba_usb_sleep_charge_set(toshiba, mode);
+	if (ret)
+		return ret;
+
+	return count;
+}
+
 static umode_t toshiba_sysfs_is_visible(struct kobject *kobj,
 					struct attribute *attr, int idx)
 {
@@ -1564,6 +1677,8 @@ static umode_t toshiba_sysfs_is_visible(struct kobject *kobj,
 		exists = (drv->touchpad_supported) ? true : false;
 	else if (attr == &dev_attr_position.attr)
 		exists = (drv->accelerometer_supported) ? true : false;
+	else if (attr == &dev_attr_usb_sleep_charge.attr)
+		exists = (drv->usb_sleep_charge_supported) ? true : false;
 
 	return exists ? attr->mode : 0;
 }
@@ -1973,6 +2088,9 @@ static int toshiba_acpi_add(struct acpi_device *acpi_dev)
 	ret = toshiba_accelerometer_supported(dev);
 	dev->accelerometer_supported = !ret;
 
+	ret = toshiba_usb_sleep_charge_get(dev, &dummy);
+	dev->usb_sleep_charge_supported = !ret;
+
 	/* Determine whether or not BIOS supports fan and video interfaces */
 
 	ret = get_video_status(dev, &dummy);