From: Oliver Neukum <oliver@xxxxxxxxxx>
This implement support in cdc-acm for acm devices another popular OS can handle
- adds support for autodetection of devices that use one interface
- autodetection of endpoints
- add a quirk for surpressing a setting that OS doesn't use
- autoassume that quirk for single interface devices
Signed-off-by: Oliver Neukum <oliver@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/usb/class/cdc-acm.c | 68 +++++++++++++++++++++++++++++++++++-------
drivers/usb/class/cdc-acm.h | 2 +
2 files changed, 58 insertions(+), 12 deletions(-)
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index ddeb691..778e023 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -937,9 +937,9 @@ static int acm_probe(struct usb_interface *intf,
int buflen = intf->altsetting->extralen;
struct usb_interface *control_interface;
struct usb_interface *data_interface;
- struct usb_endpoint_descriptor *epctrl;
- struct usb_endpoint_descriptor *epread;
- struct usb_endpoint_descriptor *epwrite;
+ struct usb_endpoint_descriptor *epctrl = NULL;
+ struct usb_endpoint_descriptor *epread = NULL;
+ struct usb_endpoint_descriptor *epwrite = NULL;
struct usb_device *usb_dev = interface_to_usbdev(intf);
struct acm *acm;
int minor;
@@ -952,6 +952,7 @@ static int acm_probe(struct usb_interface *intf,
unsigned long quirks;
int num_rx_buf;
int i;
+ int combined_interfaces = 0;
/* normal quirks */
quirks = (unsigned long)id->driver_info;
@@ -1033,9 +1034,15 @@ next_desc:
data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
control_interface = intf;
} else {
- dev_dbg(&intf->dev,
- "No union descriptor, giving up\n");
- return -ENODEV;
+ if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
+ dev_dbg(&intf->dev,"No union descriptor, giving up\n");
+ return -ENODEV;
+ } else {
+ dev_warn(&intf->dev,"No union descriptor, testing for castrated device\n");
+ combined_interfaces = 1;
+ control_interface = data_interface = intf;
+ goto look_for_collapsed_interface;
+ }
}
} else {
control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
@@ -1049,6 +1056,36 @@ next_desc:
if (data_interface_num != call_interface_num)
dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
+ if (control_interface == data_interface) {
+ /* some broken devices designed for windows work this way */
+ dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
+ combined_interfaces = 1;
+ /* a popular other OS doesn't use it */
+ quirks |= NO_CAP_LINE;
+ if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
+ dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
+ return -EINVAL;
+ }
+look_for_collapsed_interface:
+ for (i = 0; i < 3; i++) {
+ struct usb_endpoint_descriptor *ep;
+ ep = &data_interface->cur_altsetting->endpoint[i].desc;
+
+ if (usb_endpoint_is_int_in(ep))
+ epctrl = ep;
+ else if (usb_endpoint_is_bulk_out(ep))
+ epwrite = ep;
+ else if (usb_endpoint_is_bulk_in(ep))
+ epread = ep;
+ else
+ return -EINVAL;
+ }
+ if (!epctrl || !epread || !epwrite)
+ return -ENODEV;
+ else
+ goto made_compressed_probe;
+ }
+
skip_normal_probe:
/*workaround for switched interfaces */
@@ -1068,10 +1105,11 @@ skip_normal_probe:
}
/* Accept probe requests only for the control interface */
- if (intf != control_interface)
+ if (!combined_interfaces && intf != control_interface)
return -ENODEV;
- if (usb_interface_claimed(data_interface)) { /* valid in this context */
+ if (!combined_interfaces && usb_interface_claimed(data_interface)) {
+ /* valid in this context */
dev_dbg(&intf->dev, "The data interface isn't available\n");
return -EBUSY;
}
@@ -1095,6 +1133,7 @@ skip_normal_probe:
epread = epwrite;
epwrite = t;
}
+made_compressed_probe:
dbg("interfaces are valid");
for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
@@ -1112,12 +1151,15 @@ skip_normal_probe:
ctrlsize = le16_to_cpu(epctrl->wMaxPacketSize);
readsize = le16_to_cpu(epread->wMaxPacketSize) *
(quirks == SINGLE_RX_URB ? 1 : 2);
+ acm->combined_interfaces = combined_interfaces;
acm->writesize = le16_to_cpu(epwrite->wMaxPacketSize) * 20;
acm->control = control_interface;
acm->data = data_interface;
acm->minor = minor;
acm->dev = usb_dev;
acm->ctrl_caps = ac_management_function;
+ if (quirks & NO_CAP_LINE)
+ acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
acm->ctrlsize = ctrlsize;
acm->readsize = readsize;
acm->rx_buflimit = num_rx_buf;
@@ -1223,9 +1265,10 @@ skip_normal_probe:
skip_countries:
usb_fill_int_urb(acm->ctrlurb, usb_dev,
- usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
- acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
- epctrl->bInterval);
+ usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
+ acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
+ /* works around buggy devices */
+ epctrl->bInterval ? epctrl->bInterval : 0xff);
acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
acm->ctrlurb->transfer_dma = acm->ctrl_dma;
@@ -1312,7 +1355,8 @@ static void acm_disconnect(struct usb_interface *intf)
acm->ctrl_dma);
acm_read_buffers_free(acm);
- usb_driver_release_interface(&acm_driver, intf == acm->control ?
+ if (!acm->combined_interfaces)
+ usb_driver_release_interface(&acm_driver, intf == acm->control ?
acm->data : acm->control);
if (acm->port.count == 0) {
diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h
index 4c38564..1602324 100644
--- a/drivers/usb/class/cdc-acm.h
+++ b/drivers/usb/class/cdc-acm.h
@@ -125,6 +125,7 @@ struct acm {
unsigned char clocal; /* termios CLOCAL */
unsigned int ctrl_caps; /* control capabilities from the class specific header */
unsigned int susp_count; /* number of suspended interfaces */
+ int combined_interfaces:1; /* control and data collapsed */
struct acm_wb *delayed_wb; /* write queued for a device about to be woken */
};
@@ -133,3 +134,4 @@ struct acm {
/* constants describing various quirks and errors */
#define NO_UNION_NORMAL 1
#define SINGLE_RX_URB 2
+#define NO_CAP_LINE 4
--
1.6.3.2
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