Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758141AbbKSJo6 (ORCPT ); Thu, 19 Nov 2015 04:44:58 -0500 Received: from mail-yk0-f169.google.com ([209.85.160.169]:34640 "EHLO mail-yk0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756210AbbKSJo4 (ORCPT ); Thu, 19 Nov 2015 04:44:56 -0500 MIME-Version: 1.0 In-Reply-To: <564D9828.5060107@hurleysoftware.com> References: <564C9A22.2060102@hurleysoftware.com> <564D9828.5060107@hurleysoftware.com> Date: Thu, 19 Nov 2015 17:44:55 +0800 Message-ID: Subject: Re: [PATCH] usb: gadget: Add the console support for usb-to-serial port From: Baolin Wang To: Peter Hurley Cc: Felipe Balbi , Greg KH , r.baldyga@samsung.com, fabio.estevam@freescale.com, Philip Oberstaller , scottwood@freescale.com, Mark Brown , USB , LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2459 Lines: 85 On 19 November 2015 at 17:36, Peter Hurley wrote: > On 11/19/2015 01:48 AM, Baolin Wang wrote: >>> >>>> +{ >>>> + struct gscons_info *info = gserial_cons.data; >>>> + int port_num = gserial_cons.index; >>>> + struct usb_request *req; >>>> + struct gs_port *port; >>>> + struct usb_ep *ep; >>>> + >>>> + if (port_num >= MAX_U_SERIAL_PORTS || port_num < 0) { >>>> + pr_err("%s: port num [%d] exceeds the range.\n", >>>> + __func__, port_num); >>>> + return -ENXIO; >>>> + } >>>> + >>>> + port = ports[port_num].port; >>>> + if (!port) { >>>> + pr_err("%s: serial line [%d] not allocated.\n", >>>> + __func__, port_num); >>>> + return -ENODEV; >>>> + } >>>> + >>>> + if (!port->port_usb) { >>>> + pr_err("%s: no port usb.\n", __func__); >>>> + return -ENODEV; >>>> + } >>>> + >>>> + ep = port->port_usb->in; >>>> + if (!ep) { >>>> + pr_err("%s: no usb endpoint.\n", __func__); >>>> + return -ENXIO; >>>> + } >>> >>> Looking at the caller, gserial_connect(), none of the error >>> conditions above look possible. >>> >> >> I re-look the code and do some tests, I found the checking is >> necessary. Cause we get the port number from the console->index, if >> the cmdline is not set the ttyGS0 as the console, the console->index >> will be -1 that is a wrong value. Also the serial.c file will create 1 >> usb-to-seial port as default (default n_ports = 1), so we need to >> check the port and the endpoint of the port. So I think here checking >> is necessary and I have tested it. > > static void gs_console_connect(int port_num) > { > . > . > if (port_num != gserial_cons.index) > return; > . OK. Thanks. > . > > > @@ -1219,6 +1453,7 @@ int gserial_connect(struct gserial *gser, u8 port_num) > gser->disconnect(gser); > } > > + status = gs_console_connect(port_num); > spin_unlock_irqrestore(&port->port_lock, flags); > > return status; > > > > > > > -- Baolin.wang Best Regards -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/