topic Re: SAI driver can support only 32 channels on imx8 mini in i.MX Solutions

SAI driver can support only 32 channels on imx8 mini

rajeshkorabandi — Fri, 13 Dec 2024 09:45:20 GMT

Hi,

can someone tell me if there is any restriction on number of channels that are supported by sai driver in imx8 mini.

In my system, i have 8 TDM lanes and want to drive 16 channels per TDM line. total we want to do a playback of 128 channels.

in the following code is max_channels is set to 32 for playback. can i change it 128?

static struct snd_soc_dai_driver fsl_sai_dai = {

.probe = fsl_sai_dai_probe,

.playback = {

.stream_name = "CPU-Playback",

.channels_min = 1,

.channels_max = 32,

.rate_min = 8000,

.rate_max = 2822400,

.rates = SNDRV_PCM_RATE_KNOT,

.formats = FSL_SAI_FORMATS,

.capture = {

.stream_name = "CPU-Capture",

.channels_min = 1,

.channels_max = 32,

.rate_min = 8000,

.rate_max = 2822400,

.rates = SNDRV_PCM_RATE_KNOT,

.formats = FSL_SAI_FORMATS,

.resume = fsl_sai_dai_resume,

.ops = &fsl_sai_pcm_dai_ops,

};

Re: SAI driver can support only 32 channels on imx8 mini

rajeshkorabandi — Mon, 16 Dec 2024 09:25:14 GMT

Hi,

i have one more observation.

when i set the slot mask from dts file i see a failure in the driver registration.

fsl,dataline,dsd = <1 0xffff 0xffff 1 0xffff 0xffff>;

i get this error -

fsl-sai 30010000.sai: fsl,dataline,dsd: dataline cfg[0] setting error, mask is 0xff.

so does it means fsl_sai driver would not support more than 8 slots per lane?

if 16-channels per dataline is supported then the mask should allow me to set more than

Re: SAI driver can support only 32 channels on imx8 mini

rajeshkorabandi — Mon, 16 Dec 2024 10:21:48 GMT

i fixed this by increasing the datalines in this structure .dataline = 0xffff,

static struct fsl_sai_soc_data fsl_sai_imx8mq = {
.imx = true,
.dataline = 0xffff,
.fifos = 8,
.fifo_depth = 128,
.flags = 0,
.reg_offset = 8,
.constrain_period_size = false,
};

since i increased the slots to 16 should i increase the FIFO depth as well ?