usb: gadget: consider link speed for bMaxPower
The USB 2.0 specification says that bMaxPower is the maximum power
consumption expressed in 2 mA units and the USB 3.0 specification says
that it is expressed in 8 mA units.
This patch renames bMaxPower to MaxPower and the various /2 and *2 are
removed. Before reporting the config descriptor, the proper value is
computer based on the speed, all in-tree users are updated. MaxPower is
also increased to u16 so we can store the nokia gadget value which is
larger than the max value allowed for u8.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 2a6bfe7..71475b6 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -320,6 +320,25 @@
}
EXPORT_SYMBOL_GPL(usb_interface_id);
+static u8 encode_bMaxPower(enum usb_device_speed speed,
+ struct usb_configuration *c)
+{
+ unsigned val;
+
+ if (c->MaxPower)
+ val = c->MaxPower;
+ else
+ val = CONFIG_USB_GADGET_VBUS_DRAW;
+ if (!val)
+ return 0;
+ switch (speed) {
+ case USB_SPEED_SUPER:
+ return DIV_ROUND_UP(val, 8);
+ default:
+ return DIV_ROUND_UP(val, 2);
+ };
+}
+
static int config_buf(struct usb_configuration *config,
enum usb_device_speed speed, void *buf, u8 type)
{
@@ -339,7 +358,7 @@
c->bConfigurationValue = config->bConfigurationValue;
c->iConfiguration = config->iConfiguration;
c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
- c->bMaxPower = config->bMaxPower ? : (CONFIG_USB_GADGET_VBUS_DRAW / 2);
+ c->bMaxPower = encode_bMaxPower(speed, config);
/* There may be e.g. OTG descriptors */
if (config->descriptors) {
@@ -656,7 +675,7 @@
}
/* when we return, be sure our power usage is valid */
- power = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
+ power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
done:
usb_gadget_vbus_draw(gadget, power);
if (result >= 0 && cdev->delayed_status)
@@ -1518,10 +1537,10 @@
f->resume(f);
}
- maxpower = cdev->config->bMaxPower;
+ maxpower = cdev->config->MaxPower;
usb_gadget_vbus_draw(gadget, maxpower ?
- (2 * maxpower) : CONFIG_USB_GADGET_VBUS_DRAW);
+ maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
}
cdev->suspended = 0;
diff --git a/drivers/usb/gadget/gmidi.c b/drivers/usb/gadget/gmidi.c
index 881aab8..e879e2c 100644
--- a/drivers/usb/gadget/gmidi.c
+++ b/drivers/usb/gadget/gmidi.c
@@ -125,7 +125,7 @@
.bConfigurationValue = 1,
/* .iConfiguration = DYNAMIC */
.bmAttributes = USB_CONFIG_ATT_ONE,
- .bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2,
+ .MaxPower = CONFIG_USB_GADGET_VBUS_DRAW,
};
static int __init midi_bind_config(struct usb_configuration *c)
diff --git a/drivers/usb/gadget/nokia.c b/drivers/usb/gadget/nokia.c
index 661600a..1475d66 100644
--- a/drivers/usb/gadget/nokia.c
+++ b/drivers/usb/gadget/nokia.c
@@ -133,7 +133,7 @@
.bConfigurationValue = 1,
/* .iConfiguration = DYNAMIC */
.bmAttributes = USB_CONFIG_ATT_ONE,
- .bMaxPower = 250, /* 500mA */
+ .MaxPower = 500,
};
static struct usb_configuration nokia_config_100ma_driver = {
@@ -141,7 +141,7 @@
.bConfigurationValue = 2,
/* .iConfiguration = DYNAMIC */
.bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
- .bMaxPower = 50, /* 100 mA */
+ .MaxPower = 100,
};
static int __init nokia_bind(struct usb_composite_dev *cdev)
diff --git a/drivers/usb/gadget/webcam.c b/drivers/usb/gadget/webcam.c
index 69cf5c2..8cef1e6 100644
--- a/drivers/usb/gadget/webcam.c
+++ b/drivers/usb/gadget/webcam.c
@@ -336,7 +336,7 @@
.bConfigurationValue = 1,
.iConfiguration = 0, /* dynamic */
.bmAttributes = USB_CONFIG_ATT_SELFPOWER,
- .bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2,
+ .MaxPower = CONFIG_USB_GADGET_VBUS_DRAW,
};
static int /* __init_or_exit */
diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h
index b09c37e..dc512c9 100644
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -184,7 +184,8 @@
* @bConfigurationValue: Copied into configuration descriptor.
* @iConfiguration: Copied into configuration descriptor.
* @bmAttributes: Copied into configuration descriptor.
- * @bMaxPower: Copied into configuration descriptor.
+ * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the
+ * configuration descriptor after considering the bus speed.
* @cdev: assigned by @usb_add_config() before calling @bind(); this is
* the device associated with this configuration.
*
@@ -230,7 +231,7 @@
u8 bConfigurationValue;
u8 iConfiguration;
u8 bmAttributes;
- u8 bMaxPower;
+ u16 MaxPower;
struct usb_composite_dev *cdev;