2 #include <linux/usb/hcd.h>
5 static int uas_is_interface(struct usb_host_interface *intf)
7 return (intf->desc.bInterfaceClass == USB_CLASS_MASS_STORAGE &&
8 intf->desc.bInterfaceSubClass == USB_SC_SCSI &&
9 intf->desc.bInterfaceProtocol == USB_PR_UAS);
12 static int uas_find_uas_alt_setting(struct usb_interface *intf)
16 for (i = 0; i < intf->num_altsetting; i++) {
17 struct usb_host_interface *alt = &intf->altsetting[i];
19 if (uas_is_interface(alt))
20 return alt->desc.bAlternateSetting;
26 static int uas_find_endpoints(struct usb_host_interface *alt,
27 struct usb_host_endpoint *eps[])
29 struct usb_host_endpoint *endpoint = alt->endpoint;
30 unsigned i, n_endpoints = alt->desc.bNumEndpoints;
32 for (i = 0; i < n_endpoints; i++) {
33 unsigned char *extra = endpoint[i].extra;
34 int len = endpoint[i].extralen;
36 if (extra[1] == USB_DT_PIPE_USAGE) {
37 unsigned pipe_id = extra[2];
38 if (pipe_id > 0 && pipe_id < 5)
39 eps[pipe_id - 1] = &endpoint[i];
47 if (!eps[0] || !eps[1] || !eps[2] || !eps[3])
53 static int uas_use_uas_driver(struct usb_interface *intf,
54 const struct usb_device_id *id)
56 struct usb_host_endpoint *eps[4] = { };
57 struct usb_device *udev = interface_to_usbdev(intf);
58 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
59 unsigned long flags = id->driver_info;
63 alt = uas_find_uas_alt_setting(intf);
67 r = uas_find_endpoints(&intf->altsetting[alt], eps);
72 * ASM1051 and older ASM1053 devices have the same usb-id, and UAS is
73 * broken on the ASM1051, use the number of streams to differentiate.
74 * New ASM1053-s also support 32 streams, but have a different prod-id.
76 if (le16_to_cpu(udev->descriptor.idVendor) == 0x174c &&
77 le16_to_cpu(udev->descriptor.idProduct) == 0x55aa) {
78 if (udev->speed < USB_SPEED_SUPER) {
79 /* No streams info, assume ASM1051 */
80 flags |= US_FL_IGNORE_UAS;
81 } else if (usb_ss_max_streams(&eps[1]->ss_ep_comp) == 32) {
82 flags |= US_FL_IGNORE_UAS;
86 usb_stor_adjust_quirks(udev, &flags);
88 if (flags & US_FL_IGNORE_UAS) {
90 "UAS is blacklisted for this device, using usb-storage instead\n");
94 if (udev->bus->sg_tablesize == 0) {
96 "The driver for the USB controller %s does not support scatter-gather which is\n",
97 hcd->driver->description);
99 "required by the UAS driver. Please try an other USB controller if you wish to use UAS.\n");
103 if (udev->speed >= USB_SPEED_SUPER && !hcd->can_do_streams) {
105 "USB controller %s does not support streams, which are required by the UAS driver.\n",
106 hcd_to_bus(hcd)->bus_name);
108 "Please try an other USB controller if you wish to use UAS.\n");