On Tue, May 01, 2012 at 08:16:09PM +0400, Sergei Shtylyov wrote:

Hello.

On 01-05-2012 8:06, Preston Fick wrote:

quoted

This change gets the part number of the device when the driver is loaded and
stores it in the private portion of the port structure. This addition will
allow for part specific functionality to be added to the driver if needed.

quoted

Signed-off-by: Preston Fick<redacted>
---
 drivers/usb/serial/cp210x.c |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)

quoted

diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index e67ccf3..b3646b8 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c

[...]

quoted

@@ -862,6 +874,7 @@ static int cp210x_startup(struct usb_serial *serial)
 {
 	struct cp210x_port_private *port_priv;
 	int i;
+	unsigned int partNum;

 	/* cp210x buffers behave strangely unless device is reset */
 	usb_reset_device(serial->dev);

@@ -876,6 +889,17 @@ static int cp210x_startup(struct usb_serial *serial)
 		    serial->interface->cur_altsetting->desc.bInterfaceNumber;

 		usb_set_serial_port_data(serial->port[i], port_priv);
+
+		/* Get the 1-byte part number of the cp210x device */
+		usb_control_msg(serial->dev,

   This may involve DMA...

quoted

+			usb_rcvctrlpipe(serial->dev, 0),
+			CP210X_VENDOR_SPECIFIC,
+			REQTYPE_DEVICE_TO_HOST,
+			CP210X_GET_PARTNUM,
+			port_priv->bInterfaceNumber,
+			&partNum, 1,

   You can't do DMA to a buffer situated on stack. You should
kmalloc() the buffer.

You "must" kmalloc() the buffer, otherwise the driver will break on some
systems.

Sorry, I can't accept this patch because of this.  Please redo it.

greg k-h
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