From: "Rai, Amardeep" <amardeep.rai@xxxxxxxxx>
Add usb_endpoint_max_isoc_bpi() to obtain maximum bytes per interval for
isochronous endpoints in a USB version independent way.
Signed-off-by: Rai, Amardeep <amardeep.rai@xxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Co-developed-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Reviewed-by: Hans de Goede <hansg@xxxxxxxxxx>
---
drivers/usb/core/usb.c | 32 ++++++++++++++++++++++++++++++++
include/linux/usb.h | 3 +++
2 files changed, 35 insertions(+)
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index fca7735fc660..3e80a5b3e41b 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -1110,6 +1110,38 @@ void usb_free_noncoherent(struct usb_device *dev, size_t size,
}
EXPORT_SYMBOL_GPL(usb_free_noncoherent);
+/**
+ * usb_endpoint_max_isoc_bpi - Get maximum isochronous transfer bytes per interval
+ * @dev: The USB device
+ * @ep: The endpoint
+ *
+ * Returns: the maximum number of bytes isochronous endpoint @endpoint can
+ * transfer in during a service interval, or 0 for non-isochronous endpoints.
+ */
+u32 usb_endpoint_max_isoc_bpi(struct usb_device *dev,
+ const struct usb_host_endpoint *ep)
+{
+ if (usb_endpoint_type(&ep->desc) != USB_ENDPOINT_XFER_ISOC)
+ return 0;
+
+ switch (dev->speed) {
+ case USB_SPEED_SUPER_PLUS:
+ if (USB_SS_SSP_ISOC_COMP(ep->ss_ep_comp.bmAttributes))
+ return le32_to_cpu(ep->ssp_isoc_ep_comp.dwBytesPerInterval);
+ fallthrough;
+ case USB_SPEED_SUPER:
+ return le16_to_cpu(ep->ss_ep_comp.wBytesPerInterval);
+ case USB_SPEED_HIGH:
+ if (ep->eusb2_isoc_ep_comp.bDescriptorType &&
+ !usb_endpoint_maxp(&ep->desc) && usb_endpoint_dir_in(&ep->desc))
+ return le32_to_cpu(ep->eusb2_isoc_ep_comp.dwBytesPerInterval);
+ fallthrough;
+ default:
+ return usb_endpoint_maxp(&ep->desc) * usb_endpoint_maxp_mult(&ep->desc);
+ }
+}
+EXPORT_SYMBOL_GPL(usb_endpoint_max_isoc_bpi);
+
/*
* Notifications of device and interface registration
*/
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 535ac37198a1..b38978abc3d6 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -2049,6 +2049,9 @@ static inline int usb_translate_errors(int error_code)
}
}
+u32 usb_endpoint_max_isoc_bpi(struct usb_device *dev,
+ const struct usb_host_endpoint *ep);
+
/* Events from the usb core */
#define USB_DEVICE_ADD 0x0001
#define USB_DEVICE_REMOVE 0x0002
--
2.39.5
