Toshiba laptops that come with USB 3 ports have a feature that lets
them disable USB 3 functionality and act as a regular USB 2 port, and
thus, saving power.

This patch adds support to that feature, by creating a sysfs entry
named "usb_three", acceptig only two parameters, 0 to disable the
USB 3 (acting as a USB 2) and 1 to enable it, however, a reboot is
needed everytime this is toggled.

Signed-off-by: Azael Avalos <coproscef...@gmail.com>
---
 drivers/platform/x86/toshiba_acpi.c | 103 ++++++++++++++++++++++++++++++++++++
 1 file changed, 103 insertions(+)

diff --git a/drivers/platform/x86/toshiba_acpi.c 
b/drivers/platform/x86/toshiba_acpi.c
index 41f58f2..09921de 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -126,6 +126,7 @@ MODULE_LICENSE("GPL");
 #define SCI_USB_SLEEP_CHARGE           0x0150
 #define SCI_KBD_ILLUM_STATUS           0x015c
 #define SCI_USB_SLEEP_MUSIC            0x015e
+#define SCI_USB_THREE                  0x0169
 #define SCI_TOUCHPAD                   0x050e
 #define SCI_KBD_FUNCTION_KEYS          0x0522
 
@@ -196,6 +197,7 @@ struct toshiba_acpi_dev {
        unsigned int usb_sleep_music_supported:1;
        unsigned int kbd_function_keys_supported:1;
        unsigned int panel_power_on_supported:1;
+       unsigned int usb_three_supported:1;
        unsigned int sysfs_created:1;
 
        struct mutex mutex;
@@ -1078,6 +1080,51 @@ static int toshiba_panel_power_on_set(struct 
toshiba_acpi_dev *dev, u32 state)
        return 0;
 }
 
+/* USB Three */
+static int toshiba_usb_three_get(struct toshiba_acpi_dev *dev, u32 *state)
+{
+       u32 result;
+
+       if (!sci_open(dev))
+               return -EIO;
+
+       result = sci_read(dev, SCI_USB_THREE, state);
+       sci_close(dev);
+       if (result == TOS_FAILURE) {
+               pr_err("ACPI call to get USB 3 failed\n");
+               return -EIO;
+       } else if (result == TOS_NOT_SUPPORTED) {
+               pr_info("USB 3 not supported\n");
+               return -ENODEV;
+       } else if (result == TOS_INPUT_DATA_ERROR) {
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static int toshiba_usb_three_set(struct toshiba_acpi_dev *dev, u32 state)
+{
+       u32 result;
+
+       if (!sci_open(dev))
+               return -EIO;
+
+       result = sci_write(dev, SCI_USB_THREE, state);
+       sci_close(dev);
+       if (result == TOS_FAILURE) {
+               pr_err("ACPI call to set USB 3 failed\n");
+               return -EIO;
+       } else if (result == TOS_NOT_SUPPORTED) {
+               pr_info("USB 3 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)
@@ -1674,6 +1721,12 @@ static ssize_t toshiba_panel_power_on_show(struct device 
*dev,
 static ssize_t toshiba_panel_power_on_store(struct device *dev,
                                            struct device_attribute *attr,
                                            const char *buf, size_t count);
+static ssize_t toshiba_usb_three_show(struct device *dev,
+                                     struct device_attribute *attr,
+                                     char *buf);
+static ssize_t toshiba_usb_three_store(struct device *dev,
+                                      struct device_attribute *attr,
+                                      const char *buf, size_t count);
 
 static DEVICE_ATTR(version, S_IRUGO, toshiba_version_show, NULL);
 static DEVICE_ATTR(fan, S_IRUGO | S_IWUSR,
@@ -1706,6 +1759,8 @@ static DEVICE_ATTR(kbd_function_keys, S_IRUGO | S_IWUSR,
 static DEVICE_ATTR(panel_power_on, S_IRUGO | S_IWUSR,
                   toshiba_panel_power_on_show,
                   toshiba_panel_power_on_store);
+static DEVICE_ATTR(usb_three, S_IRUGO | S_IWUSR,
+                  toshiba_usb_three_show, toshiba_usb_three_store);
 
 static struct attribute *toshiba_attributes[] = {
        &dev_attr_version.attr,
@@ -1722,6 +1777,7 @@ static struct attribute *toshiba_attributes[] = {
        &dev_attr_usb_sleep_music.attr,
        &dev_attr_kbd_function_keys.attr,
        &dev_attr_panel_power_on.attr,
+       &dev_attr_usb_three.attr,
        NULL,
 };
 
@@ -2247,6 +2303,48 @@ static ssize_t toshiba_panel_power_on_store(struct 
device *dev,
        return count;
 }
 
+static ssize_t toshiba_usb_three_show(struct device *dev,
+                                     struct device_attribute *attr,
+                                     char *buf)
+{
+       struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
+       u32 state;
+       int ret;
+
+       ret = toshiba_usb_three_get(toshiba, &state);
+       if (ret < 0)
+               return ret;
+
+       return sprintf(buf, "%d\n", state);
+}
+
+static ssize_t toshiba_usb_three_store(struct device *dev,
+                                      struct device_attribute *attr,
+                                      const char *buf, size_t count)
+{
+       struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
+       int state;
+       int ret;
+
+       ret = kstrtoint(buf, 0, &state);
+       if (ret)
+               return ret;
+       /* Check for USB 3 mode where:
+        * 0 - Disabled (Acts like a USB 2 port, saving power)
+        * 1 - Enabled
+        */
+       if (state != 0 && state != 1)
+               return -EINVAL;
+
+       ret = toshiba_usb_three_set(toshiba, state);
+       if (ret)
+               return ret;
+
+       pr_info("Reboot for changes to USB 3 to take effect");
+
+       return count;
+}
+
 static umode_t toshiba_sysfs_is_visible(struct kobject *kobj,
                                        struct attribute *attr, int idx)
 {
@@ -2276,6 +2374,8 @@ static umode_t toshiba_sysfs_is_visible(struct kobject 
*kobj,
                exists = (drv->kbd_function_keys_supported) ? true : false;
        else if (attr == &dev_attr_panel_power_on.attr)
                exists = (drv->panel_power_on_supported) ? true : false;
+       else if (attr == &dev_attr_usb_three.attr)
+               exists = (drv->usb_three_supported) ? true : false;
 
        return exists ? attr->mode : 0;
 }
@@ -2700,6 +2800,9 @@ static int toshiba_acpi_add(struct acpi_device *acpi_dev)
        ret = toshiba_panel_power_on_get(dev, &dummy);
        dev->panel_power_on_supported = !ret;
 
+       ret = toshiba_usb_three_get(dev, &dummy);
+       dev->usb_three_supported = !ret;
+
        /* Determine whether or not BIOS supports fan and video interfaces */
 
        ret = get_video_status(dev, &dummy);
-- 
2.2.2

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

Reply via email to