diff options
| author | Łukasz Bartosik <ukaszb@chromium.org> | 2026-01-20 20:11:47 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-01-23 17:16:24 +0100 |
| commit | 33d15312e35d4cfd26b68ab4c1b0143cc43d8b16 (patch) | |
| tree | 00b0c4fcd8288252b3f697a07c76b522dcce5fa7 /drivers/usb/host | |
| parent | 412de639b55fcf1ab5ad50a6be84f5164104abe3 (diff) | |
xhci: dbc: allow setting product string through sysfs
Add dbc_product sysfs attribute to allow changing the product description
presented by the debug device when a host requests a string descriptor
with iProduct index.
Value can only be changed while debug capability (DbC) is in disabled
state to prevent USB device descriptor change while connected to a USB
host.
The default value is "Linux USB Debug Target".
The field length can be from 1 to 126 characters.
String is terminated at null or newline, driver does not support empty
string.
[ mn: Improve commit message and sysfs entry documentation ]
Signed-off-by: Łukasz Bartosik <ukaszb@chromium.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20260120181148.128712-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host')
| -rw-r--r-- | drivers/usb/host/xhci-dbgcap.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c index a78d386ffdc3..cae98576545e 100644 --- a/drivers/usb/host/xhci-dbgcap.c +++ b/drivers/usb/host/xhci-dbgcap.c @@ -1210,6 +1210,40 @@ static ssize_t dbc_bcdDevice_store(struct device *dev, return size; } +static ssize_t dbc_product_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_hcd *xhci = hcd_to_xhci(dev_get_drvdata(dev)); + struct xhci_dbc *dbc = xhci->dbc; + + return sysfs_emit(buf, "%s\n", dbc->str.product); +} + +static ssize_t dbc_product_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xhci_hcd *xhci = hcd_to_xhci(dev_get_drvdata(dev)); + struct xhci_dbc *dbc = xhci->dbc; + size_t len; + + if (dbc->state != DS_DISABLED) + return -EBUSY; + + len = strcspn(buf, "\n"); + if (!len) + return -EINVAL; + + if (len > USB_MAX_STRING_LEN) + return -E2BIG; + + memcpy(dbc->str.product, buf, len); + dbc->str.product[len] = '\0'; + + return size; +} + static ssize_t dbc_serial_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -1332,6 +1366,7 @@ static DEVICE_ATTR_RW(dbc_idVendor); static DEVICE_ATTR_RW(dbc_idProduct); static DEVICE_ATTR_RW(dbc_bcdDevice); static DEVICE_ATTR_RW(dbc_serial); +static DEVICE_ATTR_RW(dbc_product); static DEVICE_ATTR_RW(dbc_bInterfaceProtocol); static DEVICE_ATTR_RW(dbc_poll_interval_ms); @@ -1341,6 +1376,7 @@ static struct attribute *dbc_dev_attrs[] = { &dev_attr_dbc_idProduct.attr, &dev_attr_dbc_bcdDevice.attr, &dev_attr_dbc_serial.attr, + &dev_attr_dbc_product.attr, &dev_attr_dbc_bInterfaceProtocol.attr, &dev_attr_dbc_poll_interval_ms.attr, NULL |