linux-input.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Dan Carpenter <dan.carpenter@oracle.com>
To: benjamin.tissoires@redhat.com
Cc: linux-input@vger.kernel.org
Subject: re: HID: Introduce hidpp, a module to handle Logitech hid++ devices
Date: Fri, 31 Oct 2014 12:15:09 +0300	[thread overview]
Message-ID: <20141031091509.GB11252@mwanda> (raw)

Hello Benjamin Tissoires,

The patch 2f31c5252910: "HID: Introduce hidpp, a module to handle
Logitech hid++ devices" from Sep 30, 2014, leads to the following
static checker warning:

	drivers/hid/hid-logitech-hidpp.c:359 hidpp_root_get_protocol_version()
	warn: should this return really be negated?

drivers/hid/hid-logitech-hidpp.c
   342  static int hidpp_root_get_protocol_version(struct hidpp_device *hidpp)
   343  {
   344          struct hidpp_report response;
   345          int ret;
   346  
   347          ret = hidpp_send_fap_command_sync(hidpp,
   348                          HIDPP_PAGE_ROOT_IDX,
   349                          CMD_ROOT_GET_PROTOCOL_VERSION,
   350                          NULL, 0, &response);
   351  
   352          if (ret == 1) {
                    ^^^^^^^^
What does the "1" mean?  Magic numbers are bad, yada yada yada.

   353                  hidpp->protocol_major = 1;
   354                  hidpp->protocol_minor = 0;
   355                  return 0;
   356          }
   357  
   358          if (ret)
   359                  return -ret;
                        ^^^^^^^^^^^
This is wrong.  The real problem is that hidpp_send_fap_command_sync()
mixes normal and custom error codes.  The callers are inconsistent in
how they deal with it.

   360  
   361          hidpp->protocol_major = response.fap.params[0];
   362          hidpp->protocol_minor = response.fap.params[1];
   363  
   364          return ret;
   365  }

See also:

drivers/hid/hid-logitech-hidpp.c:398 hidpp_devicenametype_get_count() warn: should this return really be negated?
drivers/hid/hid-logitech-hidpp.c:417 hidpp_devicenametype_get_device_name() warn: should this return really be negated?
drivers/hid/hid-logitech-hidpp.c:524 hidpp_touchpad_get_raw_info() warn: should this return really be negated?

regards,
dan carpenter

             reply	other threads:[~2014-10-31  9:15 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-31  9:15 Dan Carpenter [this message]
2014-10-31 13:55 ` HID: Introduce hidpp, a module to handle Logitech hid++ devices Benjamin Tissoires

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20141031091509.GB11252@mwanda \
    --to=dan.carpenter@oracle.com \
    --cc=benjamin.tissoires@redhat.com \
    --cc=linux-input@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).