ASoC: mediatek: mt8186: remove unnecessary judgments
authorJiaxin Yu <jiaxin.yu@mediatek.com>
Tue, 26 Jul 2022 15:42:20 +0000 (23:42 +0800)
committerMark Brown <broonie@kernel.org>
Wed, 27 Jul 2022 12:14:44 +0000 (13:14 +0100)
commitd7bffbe9cbd3c96fe51a8482127cabf6fa1fd9b2
treec9c07571e131d8cfc66102ec2cb7184d830fab34
parent7df92384c86f36d0452e7abad21c7eaa91aeeef7
ASoC: mediatek: mt8186: remove unnecessary judgments

The afe_priv->dai_priv[] is allocated when platform driver probe(), if it
failed, the ASoC platform driver probe() will return fail first.
Therefore, this is excessive judgment, and the condition will never be
established.

Bug report: https://www.spinics.net/lists/alsa-devel/msg145609.html

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

The patch ae92dcbee8b6: "ASoC: mediatek: mt8186: support tdm in
platform driver" from May 23, 2022, leads to the following Smatch
complaint:

    sound/soc/mediatek/mt8186/mt8186-dai-tdm.c:424 mtk_dai_tdm_hw_params()
    warn: variable dereferenced before check 'tdm_priv' (see line 406)

sound/soc/mediatek/mt8186/mt8186-dai-tdm.c
   405 struct mtk_afe_tdm_priv *tdm_priv = afe_priv->dai_priv[tdm_id];
   406 unsigned int tdm_mode = tdm_priv->tdm_mode;
                                        ^^^^^^^^^^^^^^^^^^^
Lot's of dereferences

   407 unsigned int data_mode = tdm_priv->data_mode;
   408 unsigned int rate = params_rate(params);
   409 unsigned int channels = params_channels(params);
   410 snd_pcm_format_t format = params_format(params);
   411 unsigned int bit_width =
   412 snd_pcm_format_physical_width(format);
   413 unsigned int tdm_channels = (data_mode == TDM_DATA_ONE_PIN) ?
   414 get_tdm_ch_per_sdata(tdm_mode, channels) : 2;
   415 unsigned int lrck_width =
   416 get_tdm_lrck_width(format, tdm_mode);
   417 unsigned int tdm_con = 0;
   418 bool slave_mode = tdm_priv->slave_mode;
   419 bool lrck_inv = tdm_priv->lck_invert;
   420 bool bck_inv = tdm_priv->bck_invert;
   421 unsigned int tran_rate;
   422 unsigned int tran_relatch_rate;
   423
   424 if (!tdm_priv) {
                    ^^^^^^^^^
Checked too late

   425 dev_err(afe->dev, "%s(), tdm_priv == NULL", __func__);
   426 return -EINVAL;

Fixes: ae92dcbee8b6 ("ASoC: mediatek: mt8186: support tdm in platform driver")
Signed-off-by: Jiaxin Yu <jiaxin.yu@mediatek.com>
Link: https://lore.kernel.org/r/20220726154220.28141-1-jiaxin.yu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/mediatek/mt8186/mt8186-dai-adda.c
sound/soc/mediatek/mt8186/mt8186-dai-i2s.c
sound/soc/mediatek/mt8186/mt8186-dai-pcm.c
sound/soc/mediatek/mt8186/mt8186-dai-tdm.c