diff mbox series

[2/5] USB: serial: ir-usb: fix link-speed handling

Message ID 20200122101530.29176-3-johan@kernel.org (mailing list archive)
State Mainlined
Commit 17a0184ca17e288decdca8b2841531e34d49285f
Headers show
Series USB: serial: ir-usb fixes and cleanups | expand

Commit Message

Johan Hovold Jan. 22, 2020, 10:15 a.m. UTC
Commit e0d795e4f36c ("usb: irda: cleanup on ir-usb module") added a USB
IrDA header with common defines, but mistakingly switched to using the
class-descriptor baud-rate bitmask values for the outbound header.

This broke link-speed handling for rates above 9600 baud, but a device
would also be able to operate at the default 9600 baud until a
link-speed request was issued (e.g. using the TCGETS ioctl).

Fixes: e0d795e4f36c ("usb: irda: cleanup on ir-usb module")
Cc: stable <stable@vger.kernel.org>     # 2.6.27
Cc: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/serial/ir-usb.c | 20 ++++++++++----------
 include/linux/usb/irda.h    | 13 ++++++++++++-
 2 files changed, 22 insertions(+), 11 deletions(-)

Comments

Greg KH Jan. 22, 2020, 1:24 p.m. UTC | #1
On Wed, Jan 22, 2020 at 11:15:27AM +0100, Johan Hovold wrote:
> Commit e0d795e4f36c ("usb: irda: cleanup on ir-usb module") added a USB
> IrDA header with common defines, but mistakingly switched to using the
> class-descriptor baud-rate bitmask values for the outbound header.
> 
> This broke link-speed handling for rates above 9600 baud, but a device
> would also be able to operate at the default 9600 baud until a
> link-speed request was issued (e.g. using the TCGETS ioctl).

People still use this driver/hardware?  And this wasn't found until now?
wow...

> Fixes: e0d795e4f36c ("usb: irda: cleanup on ir-usb module")
> Cc: stable <stable@vger.kernel.org>     # 2.6.27
> Cc: Felipe Balbi <balbi@kernel.org>
> Signed-off-by: Johan Hovold <johan@kernel.org>


Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Johan Hovold Jan. 22, 2020, 1:35 p.m. UTC | #2
On Wed, Jan 22, 2020 at 02:24:50PM +0100, Greg Kroah-Hartman wrote:
> On Wed, Jan 22, 2020 at 11:15:27AM +0100, Johan Hovold wrote:
> > Commit e0d795e4f36c ("usb: irda: cleanup on ir-usb module") added a USB
> > IrDA header with common defines, but mistakingly switched to using the
> > class-descriptor baud-rate bitmask values for the outbound header.
> > 
> > This broke link-speed handling for rates above 9600 baud, but a device
> > would also be able to operate at the default 9600 baud until a
> > link-speed request was issued (e.g. using the TCGETS ioctl).
> 
> People still use this driver/hardware?  And this wasn't found until now?
> wow...

Good question. I was considering just removing the driver, but since it
would have continued to work on low and default link speed I figured I
better just fix it up.

> > Fixes: e0d795e4f36c ("usb: irda: cleanup on ir-usb module")
> > Cc: stable <stable@vger.kernel.org>     # 2.6.27
> > Cc: Felipe Balbi <balbi@kernel.org>
> > Signed-off-by: Johan Hovold <johan@kernel.org>
> 
> 
> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Thanks for reviewing.

Johan
diff mbox series

Patch

diff --git a/drivers/usb/serial/ir-usb.c b/drivers/usb/serial/ir-usb.c
index c3b06fc5a7f0..26eab1307165 100644
--- a/drivers/usb/serial/ir-usb.c
+++ b/drivers/usb/serial/ir-usb.c
@@ -335,34 +335,34 @@  static void ir_set_termios(struct tty_struct *tty,
 
 	switch (baud) {
 	case 2400:
-		ir_baud = USB_IRDA_BR_2400;
+		ir_baud = USB_IRDA_LS_2400;
 		break;
 	case 9600:
-		ir_baud = USB_IRDA_BR_9600;
+		ir_baud = USB_IRDA_LS_9600;
 		break;
 	case 19200:
-		ir_baud = USB_IRDA_BR_19200;
+		ir_baud = USB_IRDA_LS_19200;
 		break;
 	case 38400:
-		ir_baud = USB_IRDA_BR_38400;
+		ir_baud = USB_IRDA_LS_38400;
 		break;
 	case 57600:
-		ir_baud = USB_IRDA_BR_57600;
+		ir_baud = USB_IRDA_LS_57600;
 		break;
 	case 115200:
-		ir_baud = USB_IRDA_BR_115200;
+		ir_baud = USB_IRDA_LS_115200;
 		break;
 	case 576000:
-		ir_baud = USB_IRDA_BR_576000;
+		ir_baud = USB_IRDA_LS_576000;
 		break;
 	case 1152000:
-		ir_baud = USB_IRDA_BR_1152000;
+		ir_baud = USB_IRDA_LS_1152000;
 		break;
 	case 4000000:
-		ir_baud = USB_IRDA_BR_4000000;
+		ir_baud = USB_IRDA_LS_4000000;
 		break;
 	default:
-		ir_baud = USB_IRDA_BR_9600;
+		ir_baud = USB_IRDA_LS_9600;
 		baud = 9600;
 	}
 
diff --git a/include/linux/usb/irda.h b/include/linux/usb/irda.h
index 396d2b043e64..556a801efce3 100644
--- a/include/linux/usb/irda.h
+++ b/include/linux/usb/irda.h
@@ -119,11 +119,22 @@  struct usb_irda_cs_descriptor {
  * 6 - 115200 bps
  * 7 - 576000 bps
  * 8 - 1.152 Mbps
- * 9 - 5 mbps
+ * 9 - 4 Mbps
  * 10..15 - Reserved
  */
 #define USB_IRDA_STATUS_LINK_SPEED	0x0f
 
+#define USB_IRDA_LS_NO_CHANGE		0
+#define USB_IRDA_LS_2400		1
+#define USB_IRDA_LS_9600		2
+#define USB_IRDA_LS_19200		3
+#define USB_IRDA_LS_38400		4
+#define USB_IRDA_LS_57600		5
+#define USB_IRDA_LS_115200		6
+#define USB_IRDA_LS_576000		7
+#define USB_IRDA_LS_1152000		8
+#define USB_IRDA_LS_4000000		9
+
 /* The following is a 4-bit value used only for
  * outbound header:
  *