diff options
| author | Johan Hovold <johan@kernel.org> | 2014-11-06 18:08:33 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-06 12:25:40 -0800 |
| commit | 2a8cdfde9237c4e1bd7c2e68c415b006491d23cc (patch) | |
| tree | bad488692ec7149d3b326010b374f2419c80a139 /drivers/usb/class/cdc-acm.c | |
| parent | e5452dd4cb93b04b704eb6d4e7623178715f17ce (diff) | |
USB: cdc-acm: add quirk for control-line state requests
Add new quirk for devices that cannot handle control-line state
requests.
Note that we currently send these requests to all devices, regardless of
whether they claim to support it, but that errors are only logged if
support is claimed.
Since commit 0943d8ead30e ("USB: cdc-acm: use tty-port dtr_rts"), which
only changed the timings for these requests slightly, this has been
reported to cause occasional firmware crashes on Simtec Electronics
Entropy Key devices after re-enumeration. Enable the quirk for this
device.
Reported-by: Nix <nix@esperi.org.uk>
Tested-by: Nix <nix@esperi.org.uk>
Cc: stable <stable@vger.kernel.org> # v3.16
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/class/cdc-acm.c')
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 9d6495424b06..077d58ac3dcb 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -148,8 +148,15 @@ static int acm_ctrl_msg(struct acm *acm, int request, int value, /* devices aren't required to support these requests. * the cdc acm descriptor tells whether they do... */ -#define acm_set_control(acm, control) \ - acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE, control, NULL, 0) +static inline int acm_set_control(struct acm *acm, int control) +{ + if (acm->quirks & QUIRK_CONTROL_LINE_STATE) + return -EOPNOTSUPP; + + return acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE, + control, NULL, 0); +} + #define acm_set_line(acm, line) \ acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line)) #define acm_send_break(acm, ms) \ @@ -1320,6 +1327,7 @@ made_compressed_probe: tty_port_init(&acm->port); acm->port.ops = &acm_port_ops; init_usb_anchor(&acm->delayed); + acm->quirks = quirks; buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma); if (!buf) { @@ -1687,6 +1695,8 @@ static const struct usb_device_id acm_ids[] = { { USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */ .driver_info = NO_UNION_NORMAL, /* has no union descriptor */ }, + { USB_DEVICE(0x20df, 0x0001), /* Simtec Electronics Entropy Key */ + .driver_info = QUIRK_CONTROL_LINE_STATE, }, { USB_DEVICE(0x2184, 0x001c) }, /* GW Instek AFG-2225 */ { USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */ }, |