From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Hogan Subject: bugs in "ASoC: core - Optimise and refactor pcm_new() to pass only rtd"? Date: Wed, 14 Dec 2011 12:43:50 +0000 Message-ID: <4EE89A06.80101@imgtec.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , alsa-devel@alsa-project.org, linux-kernel , Neil List-Id: alsa-devel@alsa-project.org Hi, I've bisected a problem with an out of tree set of asoc drivers down to commit 552d1ef6b5a98d7b95959d5b139071e3c90cebf1 ("ASoC: core - Optimise and refactor pcm_new() to pass only rtd"). By the looks of it this change was intended not to change the workings of the code, however the dai parameter of pcm_new used to be passed codec_dai in soc_new_pcm() (initialised from rtd->codec_dai), but each driver now sets it's dai to rtd->cpu_dai instead. This seems to make the driver check the wrong dai's driver->capture.channels_min in the pcm_new callback, which makes it dereference pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream in the driver's preallocate_dma_buffer() function which can be NULL. Is this a bug (in every pcm asoc driver) that just happens not to have been noticed, or have I misunderstood it? Relevant snippets of the original patch below. Thanks James diff --git a/sound/soc/samsung/dma.c b/sound/soc/samsung/dma.c index 5cb3b88..9465588 100644 --- a/sound/soc/samsung/dma.c +++ b/sound/soc/samsung/dma.c @@ -425,9 +425,11 @@ static void dma_free_dma_buffers(struct snd_pcm *pcm) static u64 dma_mask = DMA_BIT_MASK(32); -static int dma_new(struct snd_card *card, - struct snd_soc_dai *dai, struct snd_pcm *pcm) +static int dma_new(struct snd_soc_pcm_runtime *rtd) { + struct snd_card *card = rtd->card->snd_card; + struct snd_soc_dai *dai = rtd->cpu_dai; + struct snd_pcm *pcm = rtd->pcm; int ret = 0; pr_debug("Entered %s\n", __func__); diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index c53f5d5..29bf9fb 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -2143,8 +2143,7 @@ static int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num) snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &soc_pcm_ops); if (platform->driver->pcm_new) { - ret = platform->driver->pcm_new(rtd->card->snd_card, - codec_dai, pcm); + ret = platform->driver->pcm_new(rtd); if (ret < 0) { pr_err("asoc: platform pcm constructor failed\n"); return ret;