/* * 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) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include <linux/hrtimer.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/platform_device.h> #include <linux/slab.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_SUPPORTED_DEVICE("{{SuperH DAC audio support}}"); /* 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 = ktime_set(0, 1000000000 / chip->rate); } /* PCM INTERFACE */ static 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_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *hw_params) { return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params)); } static int snd_sh_dac_pcm_hw_free(struct snd_pcm_substream *substream) { return snd_pcm_lib_free_pages(substream); } 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, snd_pcm_uframes_t pos, void __user *src, snd_pcm_uframes_t count) { /* channel is not used (interleaved data) */ struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; ssize_t b_count = frames_to_bytes(runtime , count); ssize_t b_pos = frames_to_bytes(runtime , pos); if (count < 0) return -EINVAL; if (!count) return 0; memcpy_toio(chip->data_buffer + b_pos, src, b_count); chip->buffer_end = chip->data_buffer + b_pos + b_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, snd_pcm_uframes_t pos, snd_pcm_uframes_t count) { /* channel is not used (interleaved data) */ struct snd_sh_dac *chip = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; ssize_t b_count = frames_to_bytes(runtime , count); ssize_t b_pos = frames_to_bytes(runtime , pos); if (count < 0) return -EINVAL; if (!count) return 0; memset_io(chip->data_buffer + b_pos, 0, b_count); chip->buffer_end = chip->data_buffer + b_pos + b_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 struct snd_pcm_ops snd_sh_dac_pcm_ops = { .open = snd_sh_dac_pcm_open, .close = snd_sh_dac_pcm_close, .ioctl = snd_pcm_lib_ioctl, .hw_params = snd_sh_dac_pcm_hw_params, .hw_free = snd_sh_dac_pcm_hw_free, .prepare = snd_sh_dac_pcm_prepare, .trigger = snd_sh_dac_pcm_trigger, .pointer = snd_sh_dac_pcm_pointer, .copy = snd_sh_dac_pcm_copy, .silence = snd_sh_dac_pcm_silence, .mmap = snd_pcm_lib_mmap_iomem, }; static int __devinit 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_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, snd_dma_continuous_data(GFP_KERNEL), 48 * 1024, 48 * 1024); return 0; } /* END OF PCM INTERFACE */ /* driver .remove -- destructor */ static int snd_sh_dac_remove(struct platform_device *devptr) { snd_card_free(platform_get_drvdata(devptr)); platform_set_drvdata(devptr, NULL); return 0; } /* 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 __devinit 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 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 __devinit snd_sh_dac_probe(struct platform_device *devptr) { struct snd_sh_dac *chip; struct snd_card *card; int err; err = snd_card_create(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("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 driver = { .probe = snd_sh_dac_probe, .remove = snd_sh_dac_remove, .driver = { .name = "dac_audio", }, }; static int __init sh_dac_init(void) { return platform_driver_register(&driver); } static void __exit sh_dac_exit(void) { platform_driver_unregister(&driver); } module_init(sh_dac_init); module_exit(sh_dac_exit);