[alsa-devel] [ALSA] Enable capture from line-in and CD on Revolution 5.1

[Dan Carpenter]

[ This warning is very old, but I was working on some related code and
  didn't know how to fix it ].

Hello Jochen Voss,

This is a semi-automatic email about new static checker warnings.

The patch a58e7cb16dfa: "[ALSA] Enable capture from line-in and CD on 
Revolution 5.1" from Oct 4, 2006, leads to the following Smatch 
complaint:

sound/i2c/other/ak4xxx-adda.c:808 build_adc_controls()
	 error: we previously assumed 'ak->adc_info' could be null (see line 789)

sound/i2c/other/ak4xxx-adda.c
   788			if (ak->type == SND_AK5365 && (idx % 2) == 0) {
   789				if (! ak->adc_info || 
                                      ^^^^^^^^^^^^
Old check.

   790				    ! ak->adc_info[mixer_ch].switch_name) {
   791					knew.name = "Capture Switch";
   792					knew.index = mixer_ch + ak->idx_offset * 2;
   793				} else
   794					knew.name = ak->adc_info[mixer_ch].switch_name;
   795				knew.info = ak4xxx_switch_info;
   796				knew.get = ak4xxx_switch_get;
   797				knew.put = ak4xxx_switch_put;
   798				knew.access = 0;
   799				/* register 2, bit 0 (SMUTE): 0 = normal operation,
   800				   1 = mute */
   801				knew.private_value =
   802					AK_COMPOSE(idx/2, 2, 0, 0) | AK_INVERT;
   803				err = snd_ctl_add(ak->card, snd_ctl_new1(&knew, ak));
   804				if (err < 0)
   805					return err;
   806	
   807				memset(&knew, 0, sizeof(knew));
   808				knew.name = ak->adc_info[mixer_ch].selector_name;
                                            ^^^^^^^^^^^^^^^^^^^^^
New dereference.

   809				if (!knew.name) {
   810					knew.name = "Capture Channel";

regards,
dan carpenter