From: Erik Slagter <[email protected]>
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 <[email protected]>
Signed-off-by: Maxin B. John <[email protected]>
Tested-by: Erik Slagter <[email protected]>
---
This patch applies to vanilla kernel 2.6.38.2, but I am quite
confident it will apply to any recent kernel. It was created by
Maxin John after I located the problem, slightly modified by me
and tested by me, so blame me if it breaks anything.
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index e057e53..caa2535 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 b4ea54d..683104a 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
On Wed, May 11, 2011 at 12:06:55PM +0200, Erik Slagter wrote:
> From: Erik Slagter <[email protected]>
>
> 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 <[email protected]>
> Signed-off-by: Maxin B. John <[email protected]>
> Tested-by: Erik Slagter <[email protected]>
> ---
> This patch applies to vanilla kernel 2.6.38.2, but I am quite
> confident it will apply to any recent kernel. It was created by
> Maxin John after I located the problem, slightly modified by me
> and tested by me, so blame me if it breaks anything.
If Maxin created it, it should have his "From:" on the top, right?
And did Maxin really sign-off-by: on the patch? You can not add other
people's names to that without them really doing it, that's not allowed
at all.
Care to redo it?
thanks,
greg k-h
Hi Greg,
> If Maxin created it, it should have his "From:" on the top, right?
It was a combined effort. I think, Erik has done the core part of it.
> And did Maxin really sign-off-by: on the patch? ?You can not add other
> people's names to that without them really doing it, that's not allowed
> at all.
Yes. I have added the "sign-off-by:" by myself. While we were developing and
testing the patch, we have agreed to share the fame/blame together.
> Care to redo it?
Should we really re-do it for the "sign-off-by" issue ? If it is
really required,
we are ready to redo it.
Best Regards,
Maxin
On Wed, May 11, 2011 at 03:13:37PM +0100, Maxin B John wrote:
> Hi Greg,
>
> > If Maxin created it, it should have his "From:" on the top, right?
>
> It was a combined effort. I think, Erik has done the core part of it.
Ok, and from an email I just got from Erik, that's fine.
> > And did Maxin really sign-off-by: on the patch? ?You can not add other
> > people's names to that without them really doing it, that's not allowed
> > at all.
>
> Yes. I have added the "sign-off-by:" by myself. While we were developing and
> testing the patch, we have agreed to share the fame/blame together.
Ok, I wasn't aware of this.
> > Care to redo it?
> Should we really re-do it for the "sign-off-by" issue ? If it is
> really required,
> we are ready to redo it.
No, that's fine, I was not aware that both of you agreed to this. I'll
add it to my "to-apply" queue and you will get an automated email when
it is applied to the tree.
thanks,
greg k-h
> No, that's fine, I was not aware that both of you agreed to this. I'll
> add it to my "to-apply" queue and you will get an automated email when
> it is applied to the tree.
Great, thanks!