From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [PATCH 2/3] usb: cp210x: Added in support to get and store part number Date: Wed, 2 May 2012 13:04:30 -0700 Message-ID: <20120502200430.GB25915@kroah.com> References: <1335845210-5147-1-git-send-email-preston.fick@silabs.com> <1335845210-5147-2-git-send-email-preston.fick@silabs.com> <4FA00C49.7000105@mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4FA00C49.7000105-Igf4POYTYCDQT0dZR+AlfA@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sergei Shtylyov Cc: Preston Fick , linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-serial-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, preston.fick-S6d6foEdJf7QT0dZR+AlfA@public.gmane.org List-Id: linux-serial@vger.kernel.org On Tue, May 01, 2012 at 08:16:09PM +0400, Sergei Shtylyov wrote: > Hello. > > On 01-05-2012 8:06, Preston Fick wrote: > > >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. > > >Signed-off-by: Preston Fick > >--- > > drivers/usb/serial/cp210x.c | 24 ++++++++++++++++++++++++ > > 1 files changed, 24 insertions(+), 0 deletions(-) > > >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 > [...] > >@@ -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... > > >+ 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 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html