Re: [PATCH] ASoC: amd: acp: Fix incorrect retrival of acp_chip_info

[Cezary Rojewski <cezary.rojewski@intel.com>]

On 2025-09-09 8:19 AM, Venkata Prasad Potturu wrote:
> Use dev_get_drvdata(dev->parent) instead of dev_get_platdata(dev)
> to correctly get acp_chip_info members in acp I2S driver.
> This resolves issues where some members were zero due to incorrect
> data access.

Hi,

'some members were zero' meaning null-ptr-deref? If so, please reword to 
make it more explicit.

Given the history of this file, mainly Commit 6d9b64156d84 ("ASoC: amd: 
acp: Fix NULL pointer deref in acp_i2s_set_tdm_slot") it's kind of 
surprising that the issue is addressed in staggered fashion. Why was 
set_tdm_slot() fixed separately?

> Fixes: e3933683b25e ("ASoC: amd: acp: Remove redundant acp_dev_data structure")
> 
> Signed-off-by: Venkata Prasad Potturu <venkataprasad.potturu@amd.com>

No newline between the tags, please.

> ---
>   sound/soc/amd/acp/acp-i2s.c | 11 +++++------
>   1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/sound/soc/amd/acp/acp-i2s.c b/sound/soc/amd/acp/acp-i2s.c
> index 617690362ad7..4ba0a66981ea 100644
> --- a/sound/soc/amd/acp/acp-i2s.c
> +++ b/sound/soc/amd/acp/acp-i2s.c
> @@ -73,7 +73,7 @@ static int acp_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
>   			   unsigned int fmt)
>   {
>   	struct device *dev = cpu_dai->component->dev;
> -	struct acp_chip_info *chip = dev_get_platdata(dev);
> +	struct acp_chip_info *chip = dev_get_drvdata(dev->parent);
>   	int mode;
>   
>   	mode = fmt & SND_SOC_DAIFMT_FORMAT_MASK;
> @@ -199,7 +199,7 @@ static int acp_i2s_hwparams(struct snd_pcm_substream *substream, struct snd_pcm_
>   	u32 reg_val, fmt_reg, tdm_fmt;
>   	u32 lrclk_div_val, bclk_div_val;
>   
> -	chip = dev_get_platdata(dev);
> +	chip = dev_get_drvdata(dev->parent);
>   	rsrc = chip->rsrc;
>   
>   	/* These values are as per Hardware Spec */
> @@ -386,7 +386,7 @@ static int acp_i2s_trigger(struct snd_pcm_substream *substream, int cmd, struct
>   {
>   	struct acp_stream *stream = substream->runtime->private_data;
>   	struct device *dev = dai->component->dev;
> -	struct acp_chip_info *chip = dev_get_platdata(dev);
> +	struct acp_chip_info *chip = dev_get_drvdata(dev->parent);
>   	struct acp_resource *rsrc = chip->rsrc;
>   	u32 val, period_bytes, reg_val, ier_val, water_val, buf_size, buf_reg;
>   
> @@ -516,14 +516,13 @@ static int acp_i2s_trigger(struct snd_pcm_substream *substream, int cmd, struct
>   static int acp_i2s_prepare(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
>   {
>   	struct device *dev = dai->component->dev;
> -	struct acp_chip_info *chip = dev_get_platdata(dev);
> +	struct acp_chip_info *chip = dev_get_drvdata(dev->parent);
>   	struct acp_resource *rsrc = chip->rsrc;
>   	struct acp_stream *stream = substream->runtime->private_data;
>   	u32 reg_dma_size = 0, reg_fifo_size = 0, reg_fifo_addr = 0;
>   	u32 phy_addr = 0, acp_fifo_addr = 0, ext_int_ctrl;
>   	unsigned int dir = substream->stream;
>   
> -	chip = dev_get_platdata(dev);
>   	switch (dai->driver->id) {
>   	case I2S_SP_INSTANCE:
>   		if (dir == SNDRV_PCM_STREAM_PLAYBACK) {
> @@ -632,7 +631,7 @@ static int acp_i2s_startup(struct snd_pcm_substream *substream, struct snd_soc_d
>   {
>   	struct acp_stream *stream = substream->runtime->private_data;
>   	struct device *dev = dai->component->dev;
> -	struct acp_chip_info *chip = dev_get_platdata(dev);
> +	struct acp_chip_info *chip = dev_get_drvdata(dev->parent);
>   	struct acp_resource *rsrc = chip->rsrc;
>   	unsigned int dir = substream->stream;
>   	unsigned int irq_bit = 0;