Radivoje Jovanovic wrote:
Radivoje Jovanovic wrote:
I am developing driver for a really simple hardware. Hardware has codec that supports mono/stereo and the amplifier that supports only one speaker so the driver has to be mono driver and the codec is setup to manage mono data. I have setup ALSA with following parameters:
.info = (SNDRV_PCM_INFO_NONINTERLEAVED |
Better use SNDRV_PCM_INFO_INTERLEAVED; this is the format used by almost all (stereo) sound cards, and so it is expected even for mono files (where there actually isn't any difference).
I am worried about this approach since if I want to play stereo sound I would have to increase .channels_max = 2,
No, ALSA can automatically convert the sample format.
Here is my pointer callback:
offset=READ_REG16(AUDIO_CONFIG_DMA_CUR_ADDR_HIGH))<<16) | READ_REG16(AUDIO_CONFIG_DMA_CUR_ADDR_LOW);
offset = offset - substream->runtime->dma_addr;
This offset looks as if it is in bytes, but you have to return a value measured in frames. Use bytes_to_frames().
if (offset >= runtime->buffer_size) offset = 0;
Remove this check; the ALSA framework already checks this and outputs debugging info if this happens.
Regards, Clemens