[alsa-devel] Is this bug ? dev_set/get_drvdata() of rtd

27 Jul 2016


      Hi ALSA SoC
I'm now checking ALSA SoC framework, and I noticed strange operation.
Is this bug ?
I think device data of "rtd->dev" is set as "rtd" on soc_post_component_init()
by using dev_set_drvdata(),
and many soc-core functions are based on it (= they are using dev_get_drvdata())
But, soc.h has snd_soc_pcm_set_drvdata(). 
device data of rtd->dev will be overwrite by this function ?
But is this OK ? or bug ?
It seems below drivers are using this
    sound/soc/intel/haswell/sst-haswell-pcm.c
    sound/soc/qcom/lpass-platform.c
linux/sound/soc/soc-core.c
static int soc_post_component_init(xxx)
{
    ...
    dev_set_drvdata(rtd->dev, rtd);
    ...
}
static ssize_t codec_reg_show(xxx)
{
    struct snd_soc_pcm_runtime *rtd = dev_get_drvdata(dev);
    ...
}
static ssize_t pmdown_time_show(xxx)
{
    struct snd_soc_pcm_runtime *rtd = dev_get_drvdata(dev);
    ...
}
static ssize_t pmdown_time_set(xxx)
{
    struct snd_soc_pcm_runtime *rtd = dev_get_drvdata(dev);
    ...
}
static umode_t soc_dev_attr_is_visible(xxx)
{
    struct snd_soc_pcm_runtime *rtd = dev_get_drvdata(dev);
    ...
}
linux/include/sound/soc.h
static inline void snd_soc_pcm_set_drvdata(struct snd_soc_pcm_runtime *rtd,
    	void *data)
{
    dev_set_drvdata(rtd->dev, data);
}
Best regards
---
Kuninori Morimoto