+++ /dev/null
-/*
- * Driver for the Atmel on-chip Audio Bitstream DAC (ABDAC)
- *
- * Copyright (C) 2006-2009 Atmel Corporation
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- */
-#include <linux/clk.h>
-#include <linux/bitmap.h>
-#include <linux/dmaengine.h>
-#include <linux/dma-mapping.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/types.h>
-#include <linux/io.h>
-
-#include <sound/core.h>
-#include <sound/initval.h>
-#include <sound/pcm.h>
-#include <sound/pcm_params.h>
-#include <sound/atmel-abdac.h>
-
-#include <linux/platform_data/dma-dw.h>
-#include <linux/dma/dw.h>
-
-/* DAC register offsets */
-#define DAC_DATA 0x0000
-#define DAC_CTRL 0x0008
-#define DAC_INT_MASK 0x000c
-#define DAC_INT_EN 0x0010
-#define DAC_INT_DIS 0x0014
-#define DAC_INT_CLR 0x0018
-#define DAC_INT_STATUS 0x001c
-
-/* Bitfields in CTRL */
-#define DAC_SWAP_OFFSET 30
-#define DAC_SWAP_SIZE 1
-#define DAC_EN_OFFSET 31
-#define DAC_EN_SIZE 1
-
-/* Bitfields in INT_MASK/INT_EN/INT_DIS/INT_STATUS/INT_CLR */
-#define DAC_UNDERRUN_OFFSET 28
-#define DAC_UNDERRUN_SIZE 1
-#define DAC_TX_READY_OFFSET 29
-#define DAC_TX_READY_SIZE 1
-
-/* Bit manipulation macros */
-#define DAC_BIT(name) \
- (1 << DAC_##name##_OFFSET)
-#define DAC_BF(name, value) \
- (((value) & ((1 << DAC_##name##_SIZE) - 1)) \
- << DAC_##name##_OFFSET)
-#define DAC_BFEXT(name, value) \
- (((value) >> DAC_##name##_OFFSET) \
- & ((1 << DAC_##name##_SIZE) - 1))
-#define DAC_BFINS(name, value, old) \
- (((old) & ~(((1 << DAC_##name##_SIZE) - 1) \
- << DAC_##name##_OFFSET)) \
- | DAC_BF(name, value))
-
-/* Register access macros */
-#define dac_readl(port, reg) \
- __raw_readl((port)->regs + DAC_##reg)
-#define dac_writel(port, reg, value) \
- __raw_writel((value), (port)->regs + DAC_##reg)
-
-/*
- * ABDAC supports a maximum of 6 different rates from a generic clock. The
- * generic clock has a power of two divider, which gives 6 steps from 192 kHz
- * to 5112 Hz.
- */
-#define MAX_NUM_RATES 6
-/* ALSA seems to use rates between 192000 Hz and 5112 Hz. */
-#define RATE_MAX 192000
-#define RATE_MIN 5112
-
-enum {
- DMA_READY = 0,
-};
-
-struct atmel_abdac_dma {
- struct dma_chan *chan;
- struct dw_cyclic_desc *cdesc;
-};
-
-struct atmel_abdac {
- struct clk *pclk;
- struct clk *sample_clk;
- struct platform_device *pdev;
- struct atmel_abdac_dma dma;
-
- struct snd_pcm_hw_constraint_list constraints_rates;
- struct snd_pcm_substream *substream;
- struct snd_card *card;
- struct snd_pcm *pcm;
-
- void __iomem *regs;
- unsigned long flags;
- unsigned int rates[MAX_NUM_RATES];
- unsigned int rates_num;
- int irq;
-};
-
-#define get_dac(card) ((struct atmel_abdac *)(card)->private_data)
-
-/* This function is called by the DMA driver. */
-static void atmel_abdac_dma_period_done(void *arg)
-{
- struct atmel_abdac *dac = arg;
- snd_pcm_period_elapsed(dac->substream);
-}
-
-static int atmel_abdac_prepare_dma(struct atmel_abdac *dac,
- struct snd_pcm_substream *substream,
- enum dma_data_direction direction)
-{
- struct dma_chan *chan = dac->dma.chan;
- struct dw_cyclic_desc *cdesc;
- struct snd_pcm_runtime *runtime = substream->runtime;
- unsigned long buffer_len, period_len;
-
- /*
- * We don't do DMA on "complex" transfers, i.e. with
- * non-halfword-aligned buffers or lengths.
- */
- if (runtime->dma_addr & 1 || runtime->buffer_size & 1) {
- dev_dbg(&dac->pdev->dev, "too complex transfer\n");
- return -EINVAL;
- }
-
- buffer_len = frames_to_bytes(runtime, runtime->buffer_size);
- period_len = frames_to_bytes(runtime, runtime->period_size);
-
- cdesc = dw_dma_cyclic_prep(chan, runtime->dma_addr, buffer_len,
- period_len, DMA_MEM_TO_DEV);
- if (IS_ERR(cdesc)) {
- dev_dbg(&dac->pdev->dev, "could not prepare cyclic DMA\n");
- return PTR_ERR(cdesc);
- }
-
- cdesc->period_callback = atmel_abdac_dma_period_done;
- cdesc->period_callback_param = dac;
-
- dac->dma.cdesc = cdesc;
-
- set_bit(DMA_READY, &dac->flags);
-
- return 0;
-}
-
-static struct snd_pcm_hardware atmel_abdac_hw = {
- .info = (SNDRV_PCM_INFO_MMAP
- | SNDRV_PCM_INFO_MMAP_VALID
- | SNDRV_PCM_INFO_INTERLEAVED
- | SNDRV_PCM_INFO_BLOCK_TRANSFER
- | SNDRV_PCM_INFO_RESUME
- | SNDRV_PCM_INFO_PAUSE),
- .formats = (SNDRV_PCM_FMTBIT_S16_BE),
- .rates = (SNDRV_PCM_RATE_KNOT),
- .rate_min = RATE_MIN,
- .rate_max = RATE_MAX,
- .channels_min = 2,
- .channels_max = 2,
- .buffer_bytes_max = 64 * 4096,
- .period_bytes_min = 4096,
- .period_bytes_max = 4096,
- .periods_min = 6,
- .periods_max = 64,
-};
-
-static int atmel_abdac_open(struct snd_pcm_substream *substream)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
-
- dac->substream = substream;
- atmel_abdac_hw.rate_max = dac->rates[dac->rates_num - 1];
- atmel_abdac_hw.rate_min = dac->rates[0];
- substream->runtime->hw = atmel_abdac_hw;
-
- return snd_pcm_hw_constraint_list(substream->runtime, 0,
- SNDRV_PCM_HW_PARAM_RATE, &dac->constraints_rates);
-}
-
-static int atmel_abdac_close(struct snd_pcm_substream *substream)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
- dac->substream = NULL;
- return 0;
-}
-
-static int atmel_abdac_hw_params(struct snd_pcm_substream *substream,
- struct snd_pcm_hw_params *hw_params)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
- int retval;
-
- retval = snd_pcm_lib_malloc_pages(substream,
- params_buffer_bytes(hw_params));
- if (retval < 0)
- return retval;
- /* snd_pcm_lib_malloc_pages returns 1 if buffer is changed. */
- if (retval == 1)
- if (test_and_clear_bit(DMA_READY, &dac->flags))
- dw_dma_cyclic_free(dac->dma.chan);
-
- return retval;
-}
-
-static int atmel_abdac_hw_free(struct snd_pcm_substream *substream)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
- if (test_and_clear_bit(DMA_READY, &dac->flags))
- dw_dma_cyclic_free(dac->dma.chan);
- return snd_pcm_lib_free_pages(substream);
-}
-
-static int atmel_abdac_prepare(struct snd_pcm_substream *substream)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
- int retval;
-
- retval = clk_set_rate(dac->sample_clk, 256 * substream->runtime->rate);
- if (retval)
- return retval;
-
- if (!test_bit(DMA_READY, &dac->flags))
- retval = atmel_abdac_prepare_dma(dac, substream, DMA_TO_DEVICE);
-
- return retval;
-}
-
-static int atmel_abdac_trigger(struct snd_pcm_substream *substream, int cmd)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
- int retval = 0;
-
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: /* fall through */
- case SNDRV_PCM_TRIGGER_RESUME: /* fall through */
- case SNDRV_PCM_TRIGGER_START:
- clk_prepare_enable(dac->sample_clk);
- retval = dw_dma_cyclic_start(dac->dma.chan);
- if (retval)
- goto out;
- dac_writel(dac, CTRL, DAC_BIT(EN));
- break;
- case SNDRV_PCM_TRIGGER_PAUSE_PUSH: /* fall through */
- case SNDRV_PCM_TRIGGER_SUSPEND: /* fall through */
- case SNDRV_PCM_TRIGGER_STOP:
- dw_dma_cyclic_stop(dac->dma.chan);
- dac_writel(dac, DATA, 0);
- dac_writel(dac, CTRL, 0);
- clk_disable_unprepare(dac->sample_clk);
- break;
- default:
- retval = -EINVAL;
- break;
- }
-out:
- return retval;
-}
-
-static snd_pcm_uframes_t
-atmel_abdac_pointer(struct snd_pcm_substream *substream)
-{
- struct atmel_abdac *dac = snd_pcm_substream_chip(substream);
- struct snd_pcm_runtime *runtime = substream->runtime;
- snd_pcm_uframes_t frames;
- unsigned long bytes;
-
- bytes = dw_dma_get_src_addr(dac->dma.chan);
- bytes -= runtime->dma_addr;
-
- frames = bytes_to_frames(runtime, bytes);
- if (frames >= runtime->buffer_size)
- frames -= runtime->buffer_size;
-
- return frames;
-}
-
-static irqreturn_t abdac_interrupt(int irq, void *dev_id)
-{
- struct atmel_abdac *dac = dev_id;
- u32 status;
-
- status = dac_readl(dac, INT_STATUS);
- if (status & DAC_BIT(UNDERRUN)) {
- dev_err(&dac->pdev->dev, "underrun detected\n");
- dac_writel(dac, INT_CLR, DAC_BIT(UNDERRUN));
- } else {
- dev_err(&dac->pdev->dev, "spurious interrupt (status=0x%x)\n",
- status);
- dac_writel(dac, INT_CLR, status);
- }
-
- return IRQ_HANDLED;
-}
-
-static struct snd_pcm_ops atmel_abdac_ops = {
- .open = atmel_abdac_open,
- .close = atmel_abdac_close,
- .ioctl = snd_pcm_lib_ioctl,
- .hw_params = atmel_abdac_hw_params,
- .hw_free = atmel_abdac_hw_free,
- .prepare = atmel_abdac_prepare,
- .trigger = atmel_abdac_trigger,
- .pointer = atmel_abdac_pointer,
-};
-
-static int atmel_abdac_pcm_new(struct atmel_abdac *dac)
-{
- struct snd_pcm_hardware hw = atmel_abdac_hw;
- struct snd_pcm *pcm;
- int retval;
-
- retval = snd_pcm_new(dac->card, dac->card->shortname,
- dac->pdev->id, 1, 0, &pcm);
- if (retval)
- return retval;
-
- strcpy(pcm->name, dac->card->shortname);
- pcm->private_data = dac;
- pcm->info_flags = 0;
- dac->pcm = pcm;
-
- snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &atmel_abdac_ops);
-
- retval = snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
- &dac->pdev->dev, hw.periods_min * hw.period_bytes_min,
- hw.buffer_bytes_max);
-
- return retval;
-}
-
-static bool filter(struct dma_chan *chan, void *slave)
-{
- struct dw_dma_slave *dws = slave;
-
- if (dws->dma_dev == chan->device->dev) {
- chan->private = dws;
- return true;
- } else
- return false;
-}
-
-static int set_sample_rates(struct atmel_abdac *dac)
-{
- long new_rate = RATE_MAX;
- int retval = -EINVAL;
- int index = 0;
-
- /* we start at 192 kHz and work our way down to 5112 Hz */
- while (new_rate >= RATE_MIN && index < (MAX_NUM_RATES + 1)) {
- new_rate = clk_round_rate(dac->sample_clk, 256 * new_rate);
- if (new_rate <= 0)
- break;
- /* make sure we are below the ABDAC clock */
- if (index < MAX_NUM_RATES &&
- new_rate <= clk_get_rate(dac->pclk)) {
- dac->rates[index] = new_rate / 256;
- index++;
- }
- /* divide by 256 and then by two to get next rate */
- new_rate /= 256 * 2;
- }
-
- if (index) {
- int i;
-
- /* reverse array, smallest go first */
- for (i = 0; i < (index / 2); i++) {
- unsigned int tmp = dac->rates[index - 1 - i];
- dac->rates[index - 1 - i] = dac->rates[i];
- dac->rates[i] = tmp;
- }
-
- dac->constraints_rates.count = index;
- dac->constraints_rates.list = dac->rates;
- dac->constraints_rates.mask = 0;
- dac->rates_num = index;
-
- retval = 0;
- }
-
- return retval;
-}
-
-static int atmel_abdac_probe(struct platform_device *pdev)
-{
- struct snd_card *card;
- struct atmel_abdac *dac;
- struct resource *regs;
- struct atmel_abdac_pdata *pdata;
- struct clk *pclk;
- struct clk *sample_clk;
- int retval;
- int irq;
-
- regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!regs) {
- dev_dbg(&pdev->dev, "no memory resource\n");
- return -ENXIO;
- }
-
- irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_dbg(&pdev->dev, "could not get IRQ number\n");
- return irq;
- }
-
- pdata = pdev->dev.platform_data;
- if (!pdata) {
- dev_dbg(&pdev->dev, "no platform data\n");
- return -ENXIO;
- }
-
- pclk = clk_get(&pdev->dev, "pclk");
- if (IS_ERR(pclk)) {
- dev_dbg(&pdev->dev, "no peripheral clock\n");
- return PTR_ERR(pclk);
- }
- sample_clk = clk_get(&pdev->dev, "sample_clk");
- if (IS_ERR(sample_clk)) {
- dev_dbg(&pdev->dev, "no sample clock\n");
- retval = PTR_ERR(sample_clk);
- goto out_put_pclk;
- }
- clk_prepare_enable(pclk);
-
- retval = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1,
- SNDRV_DEFAULT_STR1, THIS_MODULE,
- sizeof(struct atmel_abdac), &card);
- if (retval) {
- dev_dbg(&pdev->dev, "could not create sound card device\n");
- goto out_put_sample_clk;
- }
-
- dac = get_dac(card);
-
- dac->irq = irq;
- dac->card = card;
- dac->pclk = pclk;
- dac->sample_clk = sample_clk;
- dac->pdev = pdev;
-
- retval = set_sample_rates(dac);
- if (retval < 0) {
- dev_dbg(&pdev->dev, "could not set supported rates\n");
- goto out_free_card;
- }
-
- dac->regs = ioremap(regs->start, resource_size(regs));
- if (!dac->regs) {
- dev_dbg(&pdev->dev, "could not remap register memory\n");
- retval = -ENOMEM;
- goto out_free_card;
- }
-
- /* make sure the DAC is silent and disabled */
- dac_writel(dac, DATA, 0);
- dac_writel(dac, CTRL, 0);
-
- retval = request_irq(irq, abdac_interrupt, 0, "abdac", dac);
- if (retval) {
- dev_dbg(&pdev->dev, "could not request irq\n");
- goto out_unmap_regs;
- }
-
- if (pdata->dws.dma_dev) {
- dma_cap_mask_t mask;
-
- dma_cap_zero(mask);
- dma_cap_set(DMA_SLAVE, mask);
-
- dac->dma.chan = dma_request_channel(mask, filter, &pdata->dws);
- if (dac->dma.chan) {
- struct dma_slave_config dma_conf = {
- .dst_addr = regs->start + DAC_DATA,
- .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
- .src_maxburst = 1,
- .dst_maxburst = 1,
- .direction = DMA_MEM_TO_DEV,
- .device_fc = false,
- };
-
- dmaengine_slave_config(dac->dma.chan, &dma_conf);
- }
- }
- if (!pdata->dws.dma_dev || !dac->dma.chan) {
- dev_dbg(&pdev->dev, "DMA not available\n");
- retval = -ENODEV;
- goto out_unmap_regs;
- }
-
- strcpy(card->driver, "Atmel ABDAC");
- strcpy(card->shortname, "Atmel ABDAC");
- sprintf(card->longname, "Atmel Audio Bitstream DAC");
-
- retval = atmel_abdac_pcm_new(dac);
- if (retval) {
- dev_dbg(&pdev->dev, "could not register ABDAC pcm device\n");
- goto out_release_dma;
- }
-
- retval = snd_card_register(card);
- if (retval) {
- dev_dbg(&pdev->dev, "could not register sound card\n");
- goto out_release_dma;
- }
-
- platform_set_drvdata(pdev, card);
-
- dev_info(&pdev->dev, "Atmel ABDAC at 0x%p using %s\n",
- dac->regs, dev_name(&dac->dma.chan->dev->device));
-
- return retval;
-
-out_release_dma:
- dma_release_channel(dac->dma.chan);
- dac->dma.chan = NULL;
-out_unmap_regs:
- iounmap(dac->regs);
-out_free_card:
- snd_card_free(card);
-out_put_sample_clk:
- clk_put(sample_clk);
- clk_disable_unprepare(pclk);
-out_put_pclk:
- clk_put(pclk);
- return retval;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int atmel_abdac_suspend(struct device *pdev)
-{
- struct snd_card *card = dev_get_drvdata(pdev);
- struct atmel_abdac *dac = card->private_data;
-
- dw_dma_cyclic_stop(dac->dma.chan);
- clk_disable_unprepare(dac->sample_clk);
- clk_disable_unprepare(dac->pclk);
-
- return 0;
-}
-
-static int atmel_abdac_resume(struct device *pdev)
-{
- struct snd_card *card = dev_get_drvdata(pdev);
- struct atmel_abdac *dac = card->private_data;
-
- clk_prepare_enable(dac->pclk);
- clk_prepare_enable(dac->sample_clk);
- if (test_bit(DMA_READY, &dac->flags))
- dw_dma_cyclic_start(dac->dma.chan);
-
- return 0;
-}
-
-static SIMPLE_DEV_PM_OPS(atmel_abdac_pm, atmel_abdac_suspend, atmel_abdac_resume);
-#define ATMEL_ABDAC_PM_OPS &atmel_abdac_pm
-#else
-#define ATMEL_ABDAC_PM_OPS NULL
-#endif
-
-static int atmel_abdac_remove(struct platform_device *pdev)
-{
- struct snd_card *card = platform_get_drvdata(pdev);
- struct atmel_abdac *dac = get_dac(card);
-
- clk_put(dac->sample_clk);
- clk_disable_unprepare(dac->pclk);
- clk_put(dac->pclk);
-
- dma_release_channel(dac->dma.chan);
- dac->dma.chan = NULL;
- iounmap(dac->regs);
- free_irq(dac->irq, dac);
- snd_card_free(card);
-
- return 0;
-}
-
-static struct platform_driver atmel_abdac_driver = {
- .remove = atmel_abdac_remove,
- .driver = {
- .name = "atmel_abdac",
- .pm = ATMEL_ABDAC_PM_OPS,
- },
-};
-
-static int __init atmel_abdac_init(void)
-{
- return platform_driver_probe(&atmel_abdac_driver,
- atmel_abdac_probe);
-}
-module_init(atmel_abdac_init);
-
-static void __exit atmel_abdac_exit(void)
-{
- platform_driver_unregister(&atmel_abdac_driver);
-}
-module_exit(atmel_abdac_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Driver for Atmel Audio Bitstream DAC (ABDAC)");
-MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
projects / mirror_ubuntu-artful-kernel.git / blobdiff