Re: [alsa-devel] [PATCH] ALSA sound driver for SEGA Dreamcast AICA (pcm)

I still noticed some type cleanups, and possibly a good debug message..

On Mon, May 14, 2007 at 11:14:55PM +0100, Adrian McMenamin wrote:

+/* spu_memload - write to SPU address space */ +static void spu_memload(u32 toi, void __iomem * from, int length) +{

• u32 __iomem *froml = from;
• u32 __iomem *to = (u32 __iomem *) (SPU_MEMORY_BASE + toi);
• int i, val;

You should use "void *from" because it's not IO memory. Also, use "u32 val" since that is the native type of "u32 *from".

• length = DIV_ROUND_UP(length, 4);
• spu_write_wait();
• for (i = 0; i < length; i++) {

• val = *froml;
  

• writel(val, to);
  

• froml++;
  

• to++;
  

• if (i && !(i % 8))
  

• 	spu_write_wait();
  

• }

+}

It seems a small simplification is possible:

/* remove first spu_write_wait(); */ for (i = 0; i < length; i++) { if (!(i % 8)) spu_write_wait(); val = *froml; ... }

+/* SPU specific functions */ +/* spu_write_wait - wait for G2-SH FIFO to clear */ +static void spu_write_wait(void) +{

• int time_count;
• time_count = 0;
• while (1) {

• if (!(readl(G2_FIFO) & 0x11))
  

• 	break;
  

• /* To ensure hardware failure doesn't wedge kernel */
  

• time_count++;
  

• if (time_count > 0x10000)
  

Maybe this deserves a printk() message?

+static struct snd_pcm_hardware snd_pcm_aica_playback_hw = {

• .info = (SNDRV_PCM_INFO_NONINTERLEAVED),
• .formats =

•    (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE |
  

•     SNDRV_PCM_FMTBIT_IMA_ADPCM),
  

• .rates = SNDRV_PCM_RATE_8000_48000,
• .rate_min = 8000,
• .rate_max = 48000,
• .channels_min = 1,
• .channels_max = 2,
• .buffer_bytes_max = AICA_BUFFER_SIZE,
• .period_bytes_min = AICA_PERIOD_SIZE,
• .period_bytes_max = AICA_PERIOD_SIZE,
• .periods_min = AICA_PERIOD_NUMBER,
• .periods_max = AICA_PERIOD_NUMBER,

+};

+static int aica_dma_transfer(int channels, int buffer_size,

• 	     struct snd_pcm_substream *substream)
  

+{

• int q, err, period_offset;
• struct snd_card_aica *dreamcastcard;
• struct snd_pcm_runtime *runtime;
• err = 0;
• dreamcastcard = substream->pcm->private_data;
• period_offset = dreamcastcard->clicks;
• period_offset %= (AICA_PERIOD_NUMBER / channels);
• runtime = substream->runtime;
• for (q = 0; q < channels; q++) {

• err = dma_xfer(AICA_DMA_CHANNEL,
  

• 	       (unsigned long)(runtime->dma_area +
  

• 			       (AICA_BUFFER_SIZE * q) /
  

• 			       channels +
  

• 			       AICA_PERIOD_SIZE *
  

• 			       period_offset),
  

• 	       AICA_CHANNEL0_OFFSET + q * CHANNEL_OFFSET +
  

• 	       AICA_PERIOD_SIZE * period_offset,
  

• 	       buffer_size / channels, AICA_DMA_MODE);
  

• if (unlikely(err < 0))
  

• 	break;
  

• dma_wait_for_completion(AICA_DMA_CHANNEL);
  

• }
• return err;

+}

+static void startup_aica(struct snd_card_aica *dreamcastcard) +{

• spu_memload(AICA_CHANNEL0_CONTROL_OFFSET,

•     (u8 *) dreamcastcard->channel,
  

Why cast to u8 *? spu_memload gets a void *, and the void * is casted into an u32 *.

•     sizeof(struct aica_channel));
  

• aica_chn_start();

+}

+static void run_spu_dma(struct work_struct *work) +{

• int buffer_size;
• struct snd_pcm_substream *substream;
• struct snd_pcm_runtime *runtime;
• struct snd_card_aica *dreamcastcard;
• struct spu_work_holder *holder = container_of(work, struct spu_work_holder, spu_dma_work);
• substream = holder-> sspointer;
• dreamcastcard = substream->pcm->private_data;
• runtime = substream->runtime;
• if (unlikely(dreamcastcard->dma_check == 0)) {

• buffer_size = frames_to_bytes(runtime, runtime->buffer_size);
  

• if (runtime->channels > 1)
  

• 	dreamcastcard->channel->flags |= 0x01;
  

• aica_dma_transfer(runtime->channels, buffer_size, substream);
  

• startup_aica(dreamcastcard);
  

• dreamcastcard->clicks =
  

•     buffer_size / (AICA_PERIOD_SIZE * runtime->channels);
  

• return;
  

• } else {

• aica_dma_transfer(runtime->channels,
  

• 		  AICA_PERIOD_SIZE * runtime->channels,
  

• 		  substream);
  

• snd_pcm_period_elapsed(dreamcastcard->substream);
  

• dreamcastcard->clicks++;
  

• if (unlikely(dreamcastcard->clicks >= AICA_PERIOD_NUMBER))
  

• {
  

• 	dreamcastcard->clicks %= AICA_PERIOD_NUMBER;
  

• }
  

• mod_timer(&dreamcastcard->timer, jiffies + 1);
  

• }

+}

+static void aica_period_elapsed(unsigned long timer_var) +{

• /*timer function - so cannot sleep */
• int play_period;
• struct snd_pcm_runtime *runtime;
• struct snd_pcm_substream *substream;
• struct snd_card_aica *dreamcastcard;
• substream = (struct snd_pcm_substream *)timer_var;
• runtime = substream->runtime;
• dreamcastcard = substream->pcm->private_data;
• /* Have we played out an additional period? */
• play_period =

•    frames_to_bytes(runtime,
  

• 	    readl
  

• 	    (AICA_CONTROL_CHANNEL_SAMPLE_NUMBER)) /
  

•    AICA_PERIOD_SIZE;
  

• if (play_period == dreamcastcard->current_period) {

• /* reschedule the timer */
  

• mod_timer(&(dreamcastcard->timer), jiffies + 1);
  

• return;
  

• }
• if (runtime->channels > 1)

• dreamcastcard->current_period = play_period;
  

• if (unlikely(dreamcastcard->dma_check == 0))

• dreamcastcard->dma_check = 1;
  

• queue_work(aica_queue, &(spu_working.spu_dma_work));
  

+}

+static void spu_begin_dma(struct snd_pcm_substream *substream) +{

• /* Must be atomic */
• struct snd_card_aica *dreamcastcard;
• struct snd_pcm_runtime *runtime;
• runtime = substream->runtime;
• dreamcastcard = substream->pcm->private_data;
• /* Use queue to do the heavy lifting */
• spu_working.sspointer = substream;
• INIT_WORK(&(spu_working.spu_dma_work), run_spu_dma);
• queue_work(aica_queue, &(spu_working.spu_dma_work));
• /* Timer may already be running */
• if (unlikely(dreamcastcard->timer.data)) {

• mod_timer(&dreamcastcard->timer, jiffies + 4);
  

• return;
  

• }
• init_timer(&(dreamcastcard->timer));
• dreamcastcard->timer.data = (unsigned long)substream;
• dreamcastcard->timer.function = aica_period_elapsed;
• dreamcastcard->timer.expires = jiffies + 4;
• add_timer(&(dreamcastcard->timer));

+}

+static int snd_aicapcm_pcm_open(struct snd_pcm_substream

• 		*substream)
  

+{

• struct snd_pcm_runtime *runtime;
• struct aica_channel *channel;
• struct snd_card_aica *dreamcastcard;
• if (!enable)

• return -ENOENT;
  

• dreamcastcard = substream->pcm->private_data;
• channel = kmalloc(sizeof(struct aica_channel), GFP_KERNEL);
• if (!channel)

• return -ENOMEM;
  

• /* set defaults for channel */
• channel->sfmt = SM_8BIT;
• channel->cmd = AICA_CMD_START;
• channel->vol = dreamcastcard->master_volume;
• channel->pan = 0x80;
• channel->pos = 0;
• channel->flags = 0; /* default to mono */
• dreamcastcard->channel = channel;
• runtime = substream->runtime;
• runtime->hw = snd_pcm_aica_playback_hw;
• spu_enable();
• dreamcastcard->clicks = 0;
• dreamcastcard->current_period = 0;
• dreamcastcard->dma_check = 0;
• return 0;

+}

+static int snd_aicapcm_pcm_close(struct snd_pcm_substream

• 		 *substream)
  

+{

• struct snd_card_aica *dreamcastcard = substream->pcm->private_data;
• del_timer(&dreamcastcard->timer);
• kfree(dreamcastcard->channel);
• spu_disable();
• return 0;

+}

+static int snd_aicapcm_pcm_hw_free(struct snd_pcm_substream

• 		   *substream)
  

+{

• /* Free the DMA buffer */
• return snd_pcm_lib_free_pages(substream);

+}

+static int snd_aicapcm_pcm_hw_params(struct snd_pcm_substream

• 		     *substream, struct snd_pcm_hw_params
  

• 		     *hw_params)
  

+{

• /* Allocate a DMA buffer using ALSA built-ins */
• return

•    snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
  

+}

+static int snd_aicapcm_pcm_prepare(struct snd_pcm_substream

• 		   *substream)
  

+{

• struct snd_card_aica *dreamcastcard = substream->pcm->private_data;
• if ((substream->runtime)->format == SNDRV_PCM_FORMAT_S16_LE)

• dreamcastcard->channel->sfmt = SM_16BIT;
  

• dreamcastcard->channel->freq = substream->runtime->rate;
• dreamcastcard->substream = substream;
• return 0;

+}

+static int snd_aicapcm_pcm_trigger(struct snd_pcm_substream

• 		   *substream, int cmd)
  

+{

• struct snd_card_aica *dreamcastcard;
• switch (cmd) {
• case SNDRV_PCM_TRIGGER_START:

• spu_begin_dma(substream);
  

• break;
  

• case SNDRV_PCM_TRIGGER_STOP:

• dreamcastcard = substream->pcm->private_data;
  

• if (dreamcastcard->timer.data)
  

• 	del_timer(&dreamcastcard->timer);
  

• aica_chn_halt();
  

• break;
  

• default:

• return -EINVAL;
  

• }
• return 0;

+}

+static unsigned long snd_aicapcm_pcm_pointer(struct snd_pcm_substream

• 			     *substream)
  

+{

• return readl(AICA_CONTROL_CHANNEL_SAMPLE_NUMBER);

+}

+static struct snd_pcm_ops snd_aicapcm_playback_ops = {

• .open = snd_aicapcm_pcm_open,
• .close = snd_aicapcm_pcm_close,
• .ioctl = snd_pcm_lib_ioctl,
• .hw_params = snd_aicapcm_pcm_hw_params,
• .hw_free = snd_aicapcm_pcm_hw_free,
• .prepare = snd_aicapcm_pcm_prepare,
• .trigger = snd_aicapcm_pcm_trigger,
• .pointer = snd_aicapcm_pcm_pointer,

+};

+/* TO DO: set up to handle more than one pcm instance */ +static int __init snd_aicapcmchip(struct snd_card_aica

• 		  *dreamcastcard, int pcm_index)
  

+{

• struct snd_pcm *pcm;
• int err;
• /* AICA has no capture ability */
• err =

•    snd_pcm_new(dreamcastcard->card, "AICA PCM", pcm_index, 1, 0, &pcm);
  

• if (unlikely(err < 0))

• return err;
  

• pcm->private_data = dreamcastcard;
• strcpy(pcm->name, "AICA PCM");
• snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,

• 	&snd_aicapcm_playback_ops);
  

• /* Allocate the DMA buffers */
• err =

•    snd_pcm_lib_preallocate_pages_for_all(pcm,
  

• 				  SNDRV_DMA_TYPE_CONTINUOUS,
  

• 				  snd_dma_continuous_data
  

• 				  (GFP_KERNEL),
  

• 				  AICA_BUFFER_SIZE,
  

• 				  AICA_BUFFER_SIZE);
  

• return err;

+}

+/* Mixer controls */ +static int aica_pcmswitch_info(struct snd_kcontrol *kcontrol,

• 	       struct snd_ctl_elem_info *uinfo)
  

+{

• uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
• uinfo->count = 1;
• uinfo->value.integer.min = 0;
• uinfo->value.integer.max = 1;
• return 0;

+}

+static int aica_pcmswitch_get(struct snd_kcontrol *kcontrol,

• 	      struct snd_ctl_elem_value *ucontrol)
  

+{

• ucontrol->value.integer.value[0] = 1; /* TO DO: Fix me */
• return 0;

+}

+static int aica_pcmswitch_put(struct snd_kcontrol *kcontrol,

• 	      struct snd_ctl_elem_value *ucontrol)
  

+{

• if (ucontrol->value.integer.value[0] == 1)

• return 0;	/* TO DO: Fix me */
  

• else

• aica_chn_halt();
  

• return 0;

+}

+static int aica_pcmvolume_info(struct snd_kcontrol *kcontrol,

• 	       struct snd_ctl_elem_info *uinfo)
  

+{

• uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
• uinfo->count = 1;
• uinfo->value.integer.min = 0;
• uinfo->value.integer.max = 0xFF;
• return 0;

+}

+static int aica_pcmvolume_get(struct snd_kcontrol *kcontrol,

• 	      struct snd_ctl_elem_value *ucontrol)
  

+{

• struct snd_card_aica *dreamcastcard;
• dreamcastcard = kcontrol->private_data;
• if (unlikely(!dreamcastcard->channel))

• return -ETXTBSY;	/* we've not yet been set up */
  

• ucontrol->value.integer.value[0] = dreamcastcard->channel->vol;
• return 0;

+}

+static int aica_pcmvolume_put(struct snd_kcontrol *kcontrol,

• 	      struct snd_ctl_elem_value *ucontrol)
  

+{

• struct snd_card_aica *dreamcastcard;
• dreamcastcard = kcontrol->private_data;
• if (unlikely(!dreamcastcard->channel))

• return -ETXTBSY;
  

• if (unlikely(dreamcastcard->channel->vol ==

•      ucontrol->value.integer.value[0]))
  

• return 0;
  

• dreamcastcard->channel->vol = ucontrol->value.integer.value[0];
• dreamcastcard->master_volume = ucontrol->value.integer.value[0];
• spu_memload(AICA_CHANNEL0_CONTROL_OFFSET,

•     (u8 *) dreamcastcard->channel,
  

Unuseful cast again.