diff options
Diffstat (limited to 'sound/sh/sh_dac_audio.c')
-rw-r--r-- | sound/sh/sh_dac_audio.c | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/sound/sh/sh_dac_audio.c b/sound/sh/sh_dac_audio.c new file mode 100644 index 0000000000..95ba3abd4e --- /dev/null +++ b/sound/sh/sh_dac_audio.c @@ -0,0 +1,392 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * sh_dac_audio.c - SuperH DAC audio driver for ALSA + * + * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com> + * + * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh) + */ + +#include <linux/hrtimer.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <sound/core.h> +#include <sound/initval.h> +#include <sound/pcm.h> +#include <sound/sh_dac_audio.h> +#include <asm/clock.h> +#include <asm/hd64461.h> +#include <mach/hp6xx.h> +#include <cpu/dac.h> + +MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>"); +MODULE_DESCRIPTION("SuperH DAC audio driver"); +MODULE_LICENSE("GPL"); + +/* Module Parameters */ +static int index = SNDRV_DEFAULT_IDX1; +static char *id = SNDRV_DEFAULT_STR1; +module_param(index, int, 0444); +MODULE_PARM_DESC(index, "Index value for SuperH DAC audio."); +module_param(id, charp, 0444); +MODULE_PARM_DESC(id, "ID string for SuperH DAC audio."); + +/* main struct */ +struct snd_sh_dac { + struct snd_card *card; + struct snd_pcm_substream *substream; + struct hrtimer hrtimer; + ktime_t wakeups_per_second; + + int rate; + int empty; + char *data_buffer, *buffer_begin, *buffer_end; + int processed; /* bytes proccesed, to compare with period_size */ + int buffer_size; + struct dac_audio_pdata *pdata; +}; + + +static void dac_audio_start_timer(struct snd_sh_dac *chip) +{ + hrtimer_start(&chip->hrtimer, chip->wakeups_per_second, + HRTIMER_MODE_REL); +} + +static void dac_audio_stop_timer(struct snd_sh_dac *chip) +{ + hrtimer_cancel(&chip->hrtimer); +} + +static void dac_audio_reset(struct snd_sh_dac *chip) +{ + dac_audio_stop_timer(chip); + chip->buffer_begin = chip->buffer_end = chip->data_buffer; + chip->processed = 0; + chip->empty = 1; +} + +static void dac_audio_set_rate(struct snd_sh_dac *chip) +{ + chip->wakeups_per_second = 1000000000 / chip->rate; +} + + +/* PCM INTERFACE */ + +static const struct snd_pcm_hardware snd_sh_dac_pcm_hw = { + .info = (SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_HALF_DUPLEX), + .formats = SNDRV_PCM_FMTBIT_U8, + .rates = SNDRV_PCM_RATE_8000, + .rate_min = 8000, + .rate_max = 8000, + .channels_min = 1, + .channels_max = 1, + .buffer_bytes_max = (48*1024), + .period_bytes_min = 1, + .period_bytes_max = (48*1024), + .periods_min = 1, + .periods_max = 1024, +}; + +static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream) +{ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; + + runtime->hw = snd_sh_dac_pcm_hw; + + chip->substream = substream; + chip->buffer_begin = chip->buffer_end = chip->data_buffer; + chip->processed = 0; + chip->empty = 1; + + chip->pdata->start(chip->pdata); + + return 0; +} + +static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream) +{ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + + chip->substream = NULL; + + dac_audio_stop_timer(chip); + chip->pdata->stop(chip->pdata); + + return 0; +} + +static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream) +{ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = chip->substream->runtime; + + chip->buffer_size = runtime->buffer_size; + memset(chip->data_buffer, 0, chip->pdata->buffer_size); + + return 0; +} + +static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd) +{ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + dac_audio_start_timer(chip); + break; + case SNDRV_PCM_TRIGGER_STOP: + chip->buffer_begin = chip->buffer_end = chip->data_buffer; + chip->processed = 0; + chip->empty = 1; + dac_audio_stop_timer(chip); + break; + default: + return -EINVAL; + } + + return 0; +} + +static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream, + int channel, unsigned long pos, + struct iov_iter *src, unsigned long count) +{ + /* channel is not used (interleaved data) */ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + + if (copy_from_iter_toio(chip->data_buffer + pos, src, count)) + return -EFAULT; + chip->buffer_end = chip->data_buffer + pos + count; + + if (chip->empty) { + chip->empty = 0; + dac_audio_start_timer(chip); + } + + return 0; +} + +static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream, + int channel, unsigned long pos, + unsigned long count) +{ + /* channel is not used (interleaved data) */ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + + memset_io(chip->data_buffer + pos, 0, count); + chip->buffer_end = chip->data_buffer + pos + count; + + if (chip->empty) { + chip->empty = 0; + dac_audio_start_timer(chip); + } + + return 0; +} + +static +snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream) +{ + struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); + int pointer = chip->buffer_begin - chip->data_buffer; + + return pointer; +} + +/* pcm ops */ +static const struct snd_pcm_ops snd_sh_dac_pcm_ops = { + .open = snd_sh_dac_pcm_open, + .close = snd_sh_dac_pcm_close, + .prepare = snd_sh_dac_pcm_prepare, + .trigger = snd_sh_dac_pcm_trigger, + .pointer = snd_sh_dac_pcm_pointer, + .copy = snd_sh_dac_pcm_copy, + .fill_silence = snd_sh_dac_pcm_silence, + .mmap = snd_pcm_lib_mmap_iomem, +}; + +static int snd_sh_dac_pcm(struct snd_sh_dac *chip, int device) +{ + int err; + struct snd_pcm *pcm; + + /* device should be always 0 for us */ + err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm); + if (err < 0) + return err; + + pcm->private_data = chip; + strcpy(pcm->name, "SH_DAC PCM"); + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops); + + /* buffer size=48K */ + snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, + NULL, 48 * 1024, 48 * 1024); + + return 0; +} +/* END OF PCM INTERFACE */ + + +/* driver .remove -- destructor */ +static void snd_sh_dac_remove(struct platform_device *devptr) +{ + snd_card_free(platform_get_drvdata(devptr)); +} + +/* free -- it has been defined by create */ +static int snd_sh_dac_free(struct snd_sh_dac *chip) +{ + /* release the data */ + kfree(chip->data_buffer); + kfree(chip); + + return 0; +} + +static int snd_sh_dac_dev_free(struct snd_device *device) +{ + struct snd_sh_dac *chip = device->device_data; + + return snd_sh_dac_free(chip); +} + +static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle) +{ + struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac, + hrtimer); + struct snd_pcm_runtime *runtime = chip->substream->runtime; + ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size); + + if (!chip->empty) { + sh_dac_output(*chip->buffer_begin, chip->pdata->channel); + chip->buffer_begin++; + + chip->processed++; + if (chip->processed >= b_ps) { + chip->processed -= b_ps; + snd_pcm_period_elapsed(chip->substream); + } + + if (chip->buffer_begin == (chip->data_buffer + + chip->buffer_size - 1)) + chip->buffer_begin = chip->data_buffer; + + if (chip->buffer_begin == chip->buffer_end) + chip->empty = 1; + + } + + if (!chip->empty) + hrtimer_start(&chip->hrtimer, chip->wakeups_per_second, + HRTIMER_MODE_REL); + + return HRTIMER_NORESTART; +} + +/* create -- chip-specific constructor for the cards components */ +static int snd_sh_dac_create(struct snd_card *card, + struct platform_device *devptr, + struct snd_sh_dac **rchip) +{ + struct snd_sh_dac *chip; + int err; + + static const struct snd_device_ops ops = { + .dev_free = snd_sh_dac_dev_free, + }; + + *rchip = NULL; + + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (chip == NULL) + return -ENOMEM; + + chip->card = card; + + hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + chip->hrtimer.function = sh_dac_audio_timer; + + dac_audio_reset(chip); + chip->rate = 8000; + dac_audio_set_rate(chip); + + chip->pdata = devptr->dev.platform_data; + + chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL); + if (chip->data_buffer == NULL) { + kfree(chip); + return -ENOMEM; + } + + err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); + if (err < 0) { + snd_sh_dac_free(chip); + return err; + } + + *rchip = chip; + + return 0; +} + +/* driver .probe -- constructor */ +static int snd_sh_dac_probe(struct platform_device *devptr) +{ + struct snd_sh_dac *chip; + struct snd_card *card; + int err; + + err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card); + if (err < 0) { + snd_printk(KERN_ERR "cannot allocate the card\n"); + return err; + } + + err = snd_sh_dac_create(card, devptr, &chip); + if (err < 0) + goto probe_error; + + err = snd_sh_dac_pcm(chip, 0); + if (err < 0) + goto probe_error; + + strcpy(card->driver, "snd_sh_dac"); + strcpy(card->shortname, "SuperH DAC audio driver"); + printk(KERN_INFO "%s %s", card->longname, card->shortname); + + err = snd_card_register(card); + if (err < 0) + goto probe_error; + + snd_printk(KERN_INFO "ALSA driver for SuperH DAC audio"); + + platform_set_drvdata(devptr, card); + return 0; + +probe_error: + snd_card_free(card); + return err; +} + +/* + * "driver" definition + */ +static struct platform_driver sh_dac_driver = { + .probe = snd_sh_dac_probe, + .remove_new = snd_sh_dac_remove, + .driver = { + .name = "dac_audio", + }, +}; + +module_platform_driver(sh_dac_driver); |