[PATCH v3 09/17] media: rc: imon: Bind both interfaces via usb_driver_claim_interface()
From: Sean Young
Date: Fri Sep 04 2026 - 09:33:54 EST
iMON devices expose two USB interfaces: interface 0 (IR, and
the display/knob on older devices) and interface 1 (touchscreen/
display on newer devices).
The driver currently pieces the interface together and this has to
deal with various race conditions. Restrict the id_table to interface 0
only (USB_DEVICE_INTERFACE_NUMBER) so imon_probe() is only ever entered
once per device and then we find the second interface with
usb_driver_claim_interface(). This makes the driver much simpler.
Signed-off-by: Sean Young <sean@xxxxxxxx>
---
drivers/media/rc/imon.c | 166 +++++++++++++++++-----------------------
1 file changed, 72 insertions(+), 94 deletions(-)
diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c
index 621554005f2f..ef288cbe2b99 100644
--- a/drivers/media/rc/imon.c
+++ b/drivers/media/rc/imon.c
@@ -96,7 +96,6 @@ struct imon_context {
bool dev_present_intf1; /* USB device presence, interface 1 */
struct mutex lock; /* to lock this object */
- wait_queue_head_t remove_ok; /* For unexpected USB disconnects */
struct usb_endpoint_descriptor *rx_endpoint_intf0;
struct usb_endpoint_descriptor *rx_endpoint_intf1;
@@ -378,7 +377,7 @@ static const struct usb_device_id imon_usb_id_table[] = {
* SoundGraph iMON PAD (IR & LCD)
* SoundGraph iMON Knob (IR only)
*/
- { USB_DEVICE(0x15c2, 0xffdc),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0xffdc, 0),
.driver_info = (unsigned long)&imon_default_table },
/*
@@ -387,61 +386,61 @@ static const struct usb_device_id imon_usb_id_table[] = {
* Need user input to fill in details on unknown devices.
*/
/* SoundGraph iMON OEM Touch LCD (IR & 7" VGA LCD) */
- { USB_DEVICE(0x15c2, 0x0034),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0034, 0),
.driver_info = (unsigned long)&imon_DH102 },
/* SoundGraph iMON OEM Touch LCD (IR & 4.3" VGA LCD) */
- { USB_DEVICE(0x15c2, 0x0035),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0035, 0),
.driver_info = (unsigned long)&imon_default_table},
/* SoundGraph iMON OEM VFD (IR & VFD) */
- { USB_DEVICE(0x15c2, 0x0036),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0036, 0),
.driver_info = (unsigned long)&imon_OEM_VFD },
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x0037),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0037, 0),
.driver_info = (unsigned long)&imon_default_table},
/* SoundGraph iMON OEM LCD (IR & LCD) */
- { USB_DEVICE(0x15c2, 0x0038),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0038, 0),
.driver_info = (unsigned long)&imon_default_table},
/* SoundGraph iMON UltraBay (IR & LCD) */
- { USB_DEVICE(0x15c2, 0x0039),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0039, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x003a),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x003a, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x003b),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x003b, 0),
.driver_info = (unsigned long)&imon_default_table},
/* SoundGraph iMON OEM Inside (IR only) */
- { USB_DEVICE(0x15c2, 0x003c),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x003c, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x003d),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x003d, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x003e),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x003e, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x003f),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x003f, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x0040),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0040, 0),
.driver_info = (unsigned long)&imon_default_table},
/* SoundGraph iMON MINI (IR only) */
- { USB_DEVICE(0x15c2, 0x0041),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0041, 0),
.driver_info = (unsigned long)&imon_default_table},
/* Antec Veris Multimedia Station EZ External (IR only) */
- { USB_DEVICE(0x15c2, 0x0042),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0042, 0),
.driver_info = (unsigned long)&imon_default_table},
/* Antec Veris Multimedia Station Basic Internal (IR only) */
- { USB_DEVICE(0x15c2, 0x0043),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0043, 0),
.driver_info = (unsigned long)&imon_default_table},
/* Antec Veris Multimedia Station Elite (IR & VFD) */
- { USB_DEVICE(0x15c2, 0x0044),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0044, 0),
.driver_info = (unsigned long)&imon_default_table},
/* Antec Veris Multimedia Station Premiere (IR & LCD) */
- { USB_DEVICE(0x15c2, 0x0045),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0045, 0),
.driver_info = (unsigned long)&imon_default_table},
/* device specifics unknown */
- { USB_DEVICE(0x15c2, 0x0046),
+ { USB_DEVICE_INTERFACE_NUMBER(0x15c2, 0x0046, 0),
.driver_info = (unsigned long)&imon_default_table},
{}
};
@@ -2334,9 +2333,8 @@ static struct imon_context *imon_init_intf1(struct usb_interface *intf,
mutex_lock(&ictx->lock);
- if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
+ if (ictx->display_type == IMON_DISPLAY_TYPE_VGA)
timer_setup(&ictx->ttimer, imon_touch_display_timeout, 0);
- }
ictx->usbdev_intf1 = interface_to_usbdev(intf);
ictx->rx_urb_intf1 = rx_urb;
@@ -2363,20 +2361,32 @@ static struct imon_context *imon_init_intf1(struct usb_interface *intf,
ret = usb_submit_urb(ictx->rx_urb_intf1, GFP_KERNEL);
if (ret) {
- pr_err("usb_submit_urb failed for intf1 (%d)\n", ret);
+ dev_err(ictx->dev, "usb_submit_urb failed for intf1 (%d)\n", ret);
goto urb_submit_failed;
}
+ ret = usb_driver_claim_interface(&imon_driver, intf, ictx);
+
+ if (ret) {
+ dev_err(ictx->dev, "failed to claim second interface (%d)\n", ret);
+ goto usb_claim_failed;
+ }
+
ictx->dev_present_intf1 = true;
mutex_unlock(&ictx->lock);
+
return ictx;
+usb_claim_failed:
+ usb_kill_urb(rx_urb);
urb_submit_failed:
if (ictx->touch)
input_unregister_device(ictx->touch);
touch_setup_failed:
find_endpoint_failed:
+ if (ictx->display_type == IMON_DISPLAY_TYPE_VGA)
+ timer_delete_sync(&ictx->ttimer);
ictx->usbdev_intf1 = NULL;
mutex_unlock(&ictx->lock);
usb_free_urb(rx_urb);
@@ -2416,90 +2426,50 @@ static void imon_init_display(struct imon_context *ictx,
static int imon_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
- struct usb_device *usbdev = NULL;
- struct usb_host_interface *iface_desc = NULL;
- struct usb_interface *first_if;
+ struct usb_device *usbdev;
+ struct usb_interface *second_if;
struct device *dev = &interface->dev;
- int ifnum, sysfs_err;
- int ret = 0;
- struct imon_context *ictx = NULL;
+ int sysfs_err;
+ struct imon_context *ictx;
u16 vendor, product;
- usbdev = interface_to_usbdev(interface);
- iface_desc = interface->cur_altsetting;
- ifnum = iface_desc->desc.bInterfaceNumber;
- vendor = le16_to_cpu(usbdev->descriptor.idVendor);
- product = le16_to_cpu(usbdev->descriptor.idProduct);
-
- dev_dbg(dev, "%s: found iMON device (%04x:%04x, intf%d)\n",
- __func__, vendor, product, ifnum);
+ if (interface->cur_altsetting->desc.bInterfaceNumber != 0)
+ return -ENODEV;
- first_if = usb_ifnum_to_if(usbdev, 0);
- if (!first_if) {
- ret = -ENODEV;
- goto fail;
- }
+ usbdev = interface_to_usbdev(interface);
+ vendor = le16_to_cpu(usbdev->descriptor.idVendor);
+ product = le16_to_cpu(usbdev->descriptor.idProduct);
- if (first_if->dev.driver != interface->dev.driver) {
- dev_err(&interface->dev, "inconsistent driver matching\n");
- ret = -EINVAL;
- goto fail;
- }
+ dev_dbg(dev, "found iMON device (%04x:%04x)\n", vendor, product);
- if (ifnum == 0) {
- ictx = imon_init_intf0(interface, id);
- if (!ictx) {
- pr_err("failed to initialize context!\n");
- ret = -ENODEV;
- goto fail;
- }
- refcount_set(&ictx->users, 1);
+ ictx = imon_init_intf0(interface, id);
+ if (!ictx)
+ return -ENODEV;
- } else {
- /* this is the secondary interface on the device */
- struct imon_context *first_if_ctx = usb_get_intfdata(first_if);
+ refcount_set(&ictx->users, 1);
- /* fail early if first intf failed to register */
- if (!first_if_ctx) {
- ret = -ENODEV;
- goto fail;
- }
+ usb_set_intfdata(interface, ictx);
- ictx = imon_init_intf1(interface, first_if_ctx);
- if (!ictx) {
- pr_err("failed to attach to context!\n");
- ret = -ENODEV;
- goto fail;
- }
+ /* Newer devices export a second interface for display/touchscreen */
+ second_if = usb_ifnum_to_if(usbdev, 1);
+ if (second_if && imon_init_intf1(second_if, ictx))
refcount_inc(&ictx->users);
+ if (product == 0xffdc && ictx->rf_device) {
+ sysfs_err = sysfs_create_group(&interface->dev.kobj,
+ &imon_rf_attr_group);
+ if (sysfs_err)
+ pr_err("Could not create RF sysfs entries(%d)\n",
+ sysfs_err);
}
- usb_set_intfdata(interface, ictx);
-
- if (ifnum == 0) {
- if (product == 0xffdc && ictx->rf_device) {
- sysfs_err = sysfs_create_group(&interface->dev.kobj,
- &imon_rf_attr_group);
- if (sysfs_err)
- pr_err("Could not create RF sysfs entries(%d)\n",
- sysfs_err);
- }
-
- if (ictx->display_supported)
- imon_init_display(ictx, interface);
- }
+ if (ictx->display_supported)
+ imon_init_display(ictx, interface);
- dev_info(dev, "iMON device (%04x:%04x, intf%d) on usb<%d:%d> initialized\n",
- vendor, product, ifnum,
- usbdev->bus->busnum, usbdev->devnum);
+ dev_info(dev, "iMON device (%04x:%04x) on usb<%d:%d> initialized\n",
+ vendor, product, usbdev->bus->busnum, usbdev->devnum);
return 0;
-
-fail:
- dev_err(dev, "unable to register, err %d\n", ret);
-
- return ret;
}
/*
@@ -2507,11 +2477,15 @@ static int imon_probe(struct usb_interface *interface,
*/
static void imon_disconnect(struct usb_interface *interface)
{
+ struct usb_device *usbdev = interface_to_usbdev(interface);
+ struct usb_interface *other_if;
struct imon_context *ictx;
struct device *dev;
int ifnum;
ictx = usb_get_intfdata(interface);
+ if (!ictx)
+ return;
mutex_lock(&ictx->lock);
ictx->disconnected = true;
@@ -2547,6 +2521,7 @@ static void imon_disconnect(struct usb_interface *interface)
else if (ictx->display_type == IMON_DISPLAY_TYPE_VFD)
usb_deregister_dev(interface, &imon_vfd_class);
}
+ other_if = usb_ifnum_to_if(usbdev, 1);
} else {
ictx->dev_present_intf1 = false;
usb_kill_urb(ictx->rx_urb_intf1);
@@ -2554,13 +2529,16 @@ static void imon_disconnect(struct usb_interface *interface)
timer_delete_sync(&ictx->ttimer);
input_unregister_device(ictx->touch);
}
+ other_if = usb_ifnum_to_if(usbdev, 0);
}
+ if (other_if)
+ usb_driver_release_interface(&imon_driver, other_if);
+
if (refcount_dec_and_test(&ictx->users))
free_imon_context(ictx);
- dev_dbg(dev, "%s: iMON device (intf%d) disconnected\n",
- __func__, ifnum);
+ dev_dbg(dev, "iMON device (intf%d) disconnected\n", ifnum);
}
static int imon_suspend(struct usb_interface *intf, pm_message_t message)
--
2.55.0