From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH 2/3] usb: cp210x: Added in support to get and store part number Date: Tue, 01 May 2012 20:16:09 +0400 Message-ID: <4FA00C49.7000105@mvista.com> References: <1335845210-5147-1-git-send-email-preston.fick@silabs.com> <1335845210-5147-2-git-send-email-preston.fick@silabs.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-lpp01m010-f46.google.com ([209.85.215.46]:61452 "EHLO mail-lpp01m010-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758166Ab2EAQR5 (ORCPT ); Tue, 1 May 2012 12:17:57 -0400 Received: by lahj13 with SMTP id j13so2566131lah.19 for ; Tue, 01 May 2012 09:17:56 -0700 (PDT) In-Reply-To: <1335845210-5147-2-git-send-email-preston.fick@silabs.com> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Preston Fick Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, preston.fick@silabs.com 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. > + USB_CTRL_GET_TIMEOUT); > + port_priv->bPartNumber = partNum& 0xFF; > } > > return 0; WBR, Sergei