1 // SPDX-License-Identifier: GPL-2.0
8 #include <linux/dma-mapping.h>
68 	writel(value, priv->ai_reg_base + reg);  in n64audio_write_reg()
73 	writel(value, priv->mi_reg_base + reg);  in n64mi_write_reg()
78 	return readl(priv->mi_reg_base + reg);  in n64mi_read_reg()
83 	struct snd_pcm_runtime *runtime = priv->chan.substream->runtime;  in n64audio_push()
87 	spin_lock_irqsave(&priv->chan.lock, flags);  in n64audio_push()
89 	count = priv->chan.writesize;  in n64audio_push()
91 	memcpy(priv->ring_base + priv->chan.nextpos,  in n64audio_push()
92 	       runtime->dma_area + priv->chan.nextpos, count);  in n64audio_push()
95 	 * The hw registers are double-buffered, and the IRQ fires essentially  in n64audio_push()
99 	n64audio_write_reg(priv, AI_ADDR_REG, priv->ring_base_dma + priv->chan.nextpos);  in n64audio_push()
103 	priv->chan.nextpos += count;  in n64audio_push()
104 	priv->chan.nextpos %= priv->chan.bufsize;  in n64audio_push()
106 	runtime->delay = runtime->period_size;  in n64audio_push()
108 	spin_unlock_irqrestore(&priv->chan.lock, flags);  in n64audio_push()
123 	if (priv->chan.substream && snd_pcm_running(priv->chan.substream)) {  in n64audio_isr()
124 		spin_lock_irqsave(&priv->chan.lock, flags);  in n64audio_isr()
126 		priv->chan.pos = priv->chan.nextpos;  in n64audio_isr()
128 		spin_unlock_irqrestore(&priv->chan.lock, flags);  in n64audio_isr()
130 		snd_pcm_period_elapsed(priv->chan.substream);  in n64audio_isr()
131 		if (priv->chan.substream && snd_pcm_running(priv->chan.substream))  in n64audio_isr()
153 	// 3 periods lets the double-buffering hw read one buffer behind safely
171 	if (is_power_of_2(c->min)) {  in hw_rule_period_size()
172 		c->min += 2;  in hw_rule_period_size()
175 	if (is_power_of_2(c->max)) {  in hw_rule_period_size()
176 		c->max -= 2;  in hw_rule_period_size()
180 		c->empty = 1;  in hw_rule_period_size()
181 		return -EINVAL;  in hw_rule_period_size()
189 	struct snd_pcm_runtime *runtime = substream->runtime;  in n64audio_pcm_open()
192 	runtime->hw = n64audio_pcm_hw;  in n64audio_pcm_open()
202 			    hw_rule_period_size, NULL, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);  in n64audio_pcm_open()
211 	struct snd_pcm_runtime *runtime = substream->runtime;  in n64audio_pcm_prepare()
212 	struct n64audio *priv = substream->pcm->private_data;  in n64audio_pcm_prepare()
215 	rate = ((2 * AI_NTSC_DACRATE / runtime->rate) + 1) / 2 - 1;  in n64audio_pcm_prepare()
222 	n64audio_write_reg(priv, AI_BITCLOCK_REG, rate - 1);  in n64audio_pcm_prepare()
224 	spin_lock_irq(&priv->chan.lock);  in n64audio_pcm_prepare()
226 	/* Setup the pseudo-dma transfer pointers.  */  in n64audio_pcm_prepare()
227 	priv->chan.pos = 0;  in n64audio_pcm_prepare()
228 	priv->chan.nextpos = 0;  in n64audio_pcm_prepare()
229 	priv->chan.substream = substream;  in n64audio_pcm_prepare()
230 	priv->chan.writesize = snd_pcm_lib_period_bytes(substream);  in n64audio_pcm_prepare()
231 	priv->chan.bufsize = snd_pcm_lib_buffer_bytes(substream);  in n64audio_pcm_prepare()
233 	spin_unlock_irq(&priv->chan.lock);  in n64audio_pcm_prepare()
240 	struct n64audio *priv = substream->pcm->private_data;  in n64audio_pcm_trigger()
244 		n64audio_push(substream->pcm->private_data);  in n64audio_pcm_trigger()
253 		return -EINVAL;  in n64audio_pcm_trigger()
260 	struct n64audio *priv = substream->pcm->private_data;  in n64audio_pcm_pointer()
262 	return bytes_to_frames(substream->runtime,  in n64audio_pcm_pointer()
263 			       priv->chan.pos);  in n64audio_pcm_pointer()
268 	struct n64audio *priv = substream->pcm->private_data;  in n64audio_pcm_close()
270 	priv->chan.substream = NULL;  in n64audio_pcm_close()
284  * The target device is embedded and RAM-constrained. We save RAM
295 	err = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,  in n64audio_probe()
301 	priv = card->private_data;  in n64audio_probe()
303 	spin_lock_init(&priv->chan.lock);  in n64audio_probe()
305 	priv->card = card;  in n64audio_probe()
307 	priv->ring_base = dma_alloc_coherent(card->dev, 32 * 1024, &priv->ring_base_dma,  in n64audio_probe()
309 	if (!priv->ring_base) {  in n64audio_probe()
310 		err = -ENOMEM;  in n64audio_probe()
314 	priv->mi_reg_base = devm_platform_ioremap_resource(pdev, 0);  in n64audio_probe()
315 	if (IS_ERR(priv->mi_reg_base)) {  in n64audio_probe()
316 		err = PTR_ERR(priv->mi_reg_base);  in n64audio_probe()
320 	priv->ai_reg_base = devm_platform_ioremap_resource(pdev, 1);  in n64audio_probe()
321 	if (IS_ERR(priv->ai_reg_base)) {  in n64audio_probe()
322 		err = PTR_ERR(priv->ai_reg_base);  in n64audio_probe()
330 	pcm->private_data = priv;  in n64audio_probe()
331 	strscpy(pcm->name, "N64 Audio");  in n64audio_probe()
334 	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, card->dev, 0, 0);  in n64audio_probe()
336 	strscpy(card->driver, "N64 Audio");  in n64audio_probe()
337 	strscpy(card->shortname, "N64 Audio");  in n64audio_probe()
338 	strscpy(card->longname, "N64 Audio");  in n64audio_probe()
342 		err = -EINVAL;  in n64audio_probe()
345 	if (devm_request_irq(&pdev->dev, irq, n64audio_isr,  in n64audio_probe()
347 		err = -EBUSY;  in n64audio_probe()
358 	dma_free_coherent(card->dev, 32 * 1024, priv->ring_base, priv->ring_base_dma);  in n64audio_probe()