diff options
| author | Erik Slagter <erik@slagter.name> | 2011-05-11 12:06:55 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-06-03 10:34:24 +0900 |
| commit | ed25d77e109b1c90e999e77f51f00b6bf6b75bae (patch) | |
| tree | 1d549b8e993b9ae388d25be076187acd21d36641 /drivers | |
| parent | 33730250bc0b5d432e7fb37e5a95ff77e10e1364 (diff) | |
| download | lwn-ed25d77e109b1c90e999e77f51f00b6bf6b75bae.tar.gz lwn-ed25d77e109b1c90e999e77f51f00b6bf6b75bae.zip | |
USB: cdc_acm: Fix oops when Droids MuIn LCD is connected
commit fd5054c169d29747a44b4e1419ff47f57ae82dbc upstream.
The Droids MuIn LCD operates like a serial remote terminal.
Data received are displayed directly on the LCD. This patch
fixes the kernel null pointer oops when it is plugged in.
Add NO_DATA_INTERFACE quirk to tell the driver that "control"
and "data" interfaces are not separated for this device, which
prevents dereferencing a null pointer in the device probe code.
Signed-off-by: Erik Slagter <erik@slagter.name>
Signed-off-by: Maxin B. John <maxin.john@gmail.com>
Tested-by: Erik Slagter <erik@slagter.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 13 | ||||
| -rw-r--r-- | drivers/usb/class/cdc-acm.h | 1 |
2 files changed, 12 insertions, 2 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 30bb8d053c2e..83589f49efde 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -946,7 +946,7 @@ static int acm_probe(struct usb_interface *intf, u8 ac_management_function = 0; u8 call_management_function = 0; int call_interface_num = -1; - int data_interface_num; + int data_interface_num = -1; unsigned long quirks; int num_rx_buf; int i; @@ -1030,7 +1030,11 @@ next_desc: if (!union_header) { if (call_interface_num > 0) { dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n"); - data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num)); + /* quirks for Droids MuIn LCD */ + if (quirks & NO_DATA_INTERFACE) + data_interface = usb_ifnum_to_if(usb_dev, 0); + else + data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num)); control_interface = intf; } else { if (intf->cur_altsetting->desc.bNumEndpoints != 3) { @@ -1622,6 +1626,11 @@ static const struct usb_device_id acm_ids[] = { .driver_info = NOT_A_MODEM, }, + /* Support for Droids MuIn LCD */ + { USB_DEVICE(0x04d8, 0x000b), + .driver_info = NO_DATA_INTERFACE, + }, + /* control interfaces without any protocol set */ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, USB_CDC_PROTO_NONE) }, diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index 5eeb570b9a61..a2446d6caf05 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -137,3 +137,4 @@ struct acm { #define SINGLE_RX_URB 2 #define NO_CAP_LINE 4 #define NOT_A_MODEM 8 +#define NO_DATA_INTERFACE 16 |