// SPDX-License-Identifier: (GPL-2.0 OR MIT)
//
// Copyright (c) 2018 BayLibre, SAS.
// Author: Jerome Brunet <[email protected]>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <sound/soc.h>
#include "axg-tdm-formatter.h"
struct axg_tdm_formatter {
struct list_head list;
struct axg_tdm_stream *stream;
const struct axg_tdm_formatter_driver *drv;
struct clk *pclk;
struct clk *sclk;
struct clk *lrclk;
struct clk *sclk_sel;
struct clk *lrclk_sel;
struct reset_control *reset;
bool enabled;
struct regmap *map;
};
int axg_tdm_formatter_set_channel_masks(struct regmap *map,
struct axg_tdm_stream *ts,
unsigned int offset)
{
unsigned int ch = ts->channels;
u32 val[AXG_TDM_NUM_LANES];
int i, j, k;
/*
* We need to mimick the slot distribution used by the HW to keep the
* channel placement consistent regardless of the number of channel
* in the stream. This is why the odd algorithm below is used.
*/
memset(val, 0, sizeof(*val) * AXG_TDM_NUM_LANES);
/*
* Distribute the channels of the stream over the available slots
* of each TDM lane. We need to go over the 32 slots ...
*/
for (i = 0; (i < 32) && ch; i += 2) {
/* ... of all the lanes ... */
for (j = 0; j < AXG_TDM_NUM_LANES; j++) {
/* ... then distribute the channels in pairs */
for (k = 0; k < 2; k++) {
if ((BIT(i + k) & ts->mask[j]) && ch) {
val[j] |= BIT(i + k);
ch -= 1;
}
}
}
}
/*
* If we still have channel left at the end of the process, it means
* the stream has more channels than we can accommodate and we should
* have caught this earlier.
*/
if (WARN_ON(ch != 0)) {
pr_err("channel mask error\n");
return -EINVAL;
}
for (i = 0; i < AXG_TDM_NUM_LANES; i++) {
regmap_write(map, offset, val[i]);
offset += regmap_get_reg_stride(map);
}
return 0;
}
EXPORT_SYMBOL_GPL(axg_tdm_formatter_set_channel_masks);
static int axg_tdm_formatter_enable(struct axg_tdm_formatter *formatter)
{
struct axg_tdm_stream *ts = formatter->stream;
bool invert;
int ret;
/* Do nothing if the formatter is already enabled */
if (formatter->enabled)
return 0;
/*
* On the g12a (and possibly other SoCs), when a stream using
* multiple lanes is restarted, it will sometimes not start
* from the first lane, but randomly from another used one.
* The result is an unexpected and random channel shift.
*
* The hypothesis is that an HW counter is not properly reset
* and the formatter simply starts on the lane it stopped
* before. Unfortunately, there does not seems to be a way to
* reset this through the registers of the block.
*
* However, the g12a has indenpendent reset lines for each audio
* devices. Using this reset before each start solves the issue.
*/
ret = reset_control_reset(formatter->reset);
if (ret)
return ret;
/*
* If sclk is inverted, it means the bit should latched on the
* rising edge which is what our HW expects. If not, we need to
* invert it before the formatter.
*/
invert = axg_tdm_sclk_invert(ts->iface->fmt);
ret = clk_set_phase(formatter->sclk, invert ? 0 : 180);
if (ret)
return ret;
/* Setup the stream parameter in the formatter */
ret = formatter->drv->ops->prepare(formatter->map,
formatter->drv->quirks,
formatter->stream);
if (ret)
return ret;
/* Enable the signal clocks feeding the formatter */
ret = clk_prepare_enable(formatter->sclk);
if (ret)
return ret;
ret = clk_prepare_enable(formatter->lrclk);
if (ret) {
clk_disable_unprepare(formatter->sclk);
return ret;
}
/* Finally, actually enable the formatter */
formatter->drv->ops->enable(formatter->map);
formatter->enabled = true;
return 0;
}
static void axg_tdm_formatter_disable(struct axg_tdm_formatter *formatter)
{
/* Do nothing if the formatter is already disabled */
if (!formatter->enabled)
return;
formatter->drv->ops->disable(formatter->map);
clk_disable_unprepare(formatter->lrclk);
clk_disable_unprepare(formatter->sclk);
formatter->enabled = false;
}
static int axg_tdm_formatter_attach(struct axg_tdm_formatter *formatter)
{
struct axg_tdm_stream *ts = formatter->stream;
int ret = 0;
mutex_lock(&ts->lock);
/* Catch up if the stream is already running when we attach */
if (ts->ready) {
ret = axg_tdm_formatter_enable(formatter);
if (ret) {
pr_err("failed to enable formatter\n");
goto out;
}
}
list_add_tail(&formatter->list, &ts->formatter_list);
out:
mutex_unlock(&ts->lock);
return ret;
}
static void axg_tdm_formatter_dettach(struct axg_tdm_formatter *formatter)
{
struct axg_tdm_stream *ts = formatter->stream;
mutex_lock(&ts->lock);
list_del(&formatter->list);
mutex_unlock(&ts->lock);
axg_tdm_formatter_disable(formatter);
}
static int axg_tdm_formatter_power_up(struct axg_tdm_formatter *formatter,
struct snd_soc_dapm_widget *w)
{
struct axg_tdm_stream *ts = formatter->drv->ops->get_stream(w);
int ret;
/*
* If we don't get a stream at this stage, it would mean that the
* widget is powering up but is not attached to any backend DAI.
* It should not happen, ever !
*/
if (WARN_ON(!ts))
return -ENODEV;
/* Clock our device */
ret = clk_prepare_enable(formatter->pclk);
if (ret)
return ret;
/* Reparent the bit clock to the TDM interface */
ret = clk_set_parent(formatter->sclk_sel, ts->iface->sclk);
if (ret)
goto disable_pclk;
/* Reparent the sample clock to the TDM interface */
ret = clk_set_parent(formatter->lrclk_sel, ts->iface->lrclk);
if (ret)
goto disable_pclk;
formatter->stream = ts;
ret = axg_tdm_formatter_attach(formatter);
if (ret)
goto disable_pclk;
return 0;
disable_pclk:
clk_disable_unprepare(formatter->pclk);
return ret;
}
static void axg_tdm_formatter_power_down(struct axg_tdm_formatter *formatter)
{
axg_tdm_formatter_dettach(formatter);
clk_disable_unprepare(formatter->pclk);
formatter->stream = NULL;
}
int axg_tdm_formatter_event(struct snd_soc_dapm_widget *w,
struct snd_kcontrol *control,
int event)
{
struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
struct axg_tdm_formatter *formatter = snd_soc_component_get_drvdata(c);
int ret = 0;
switch (event) {
case SND_SOC_DAPM_PRE_PMU:
ret = axg_tdm_formatter_power_up(formatter, w);
break;
case SND_SOC_DAPM_PRE_PMD:
axg_tdm_formatter_power_down(formatter);
break;
default:
dev_err(c->dev, "Unexpected event %d\n", event);
return -EINVAL;
}
return ret;
}
EXPORT_SYMBOL_GPL(axg_tdm_formatter_event);
int axg_tdm_formatter_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
const struct axg_tdm_formatter_driver *drv;
struct axg_tdm_formatter *formatter;
void __iomem *regs;
drv = of_device_get_match_data(dev);
if (!drv) {
dev_err(dev, "failed to match device\n");
return -ENODEV;
}
formatter = devm_kzalloc(dev, sizeof(*formatter), GFP_KERNEL);
if (!formatter)
return -ENOMEM;
platform_set_drvdata(pdev, formatter);
formatter->drv = drv;
regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(regs))
return PTR_ERR(regs);
formatter->map = devm_regmap_init_mmio(dev, regs, drv->regmap_cfg);
if (IS_ERR(formatter->map)) {
dev_err(dev, "failed to init regmap: %ld\n",
PTR_ERR(formatter->map));
return PTR_ERR(formatter->map);
}
/* Peripharal clock */
formatter->pclk = devm_clk_get(dev, "pclk");
if (IS_ERR(formatter->pclk))
return dev_err_probe(dev, PTR_ERR(formatter->pclk), "failed to get pclk\n");
/* Formatter bit clock */
formatter->sclk = devm_clk_get(dev, "sclk");
if (IS_ERR(formatter->sclk))
return dev_err_probe(dev, PTR_ERR(formatter->sclk), "failed to get sclk\n");
/* Formatter sample clock */
formatter->lrclk = devm_clk_get(dev, "lrclk");
if (IS_ERR(formatter->lrclk))
return dev_err_probe(dev, PTR_ERR(formatter->lrclk), "failed to get lrclk\n");
/* Formatter bit clock input multiplexer */
formatter->sclk_sel = devm_clk_get(dev, "sclk_sel");
if (IS_ERR(formatter->sclk_sel))
return dev_err_probe(dev, PTR_ERR(formatter->sclk_sel), "failed to get sclk_sel\n");
/* Formatter sample clock input multiplexer */
formatter->lrclk_sel = devm_clk_get(dev, "lrclk_sel");
if (IS_ERR(formatter->lrclk_sel))
return dev_err_probe(dev, PTR_ERR(formatter->lrclk_sel),
"failed to get lrclk_sel\n");
/* Formatter dedicated reset line */
formatter->reset = devm_reset_control_get_optional_exclusive(dev, NULL);
if (IS_ERR(formatter->reset))
return dev_err_probe(dev, PTR_ERR(formatter->reset), "failed to get reset\n");
return devm_snd_soc_register_component(dev, drv->component_drv,
NULL, 0);
}
EXPORT_SYMBOL_GPL(axg_tdm_formatter_probe);
int axg_tdm_stream_start(struct axg_tdm_stream *ts)
{
struct axg_tdm_formatter *formatter;
int ret = 0;
mutex_lock(&ts->lock);
ts->ready = true;
/* Start all the formatters attached to the stream */
list_for_each_entry(formatter, &ts->formatter_list, list) {
ret = axg_tdm_formatter_enable(formatter);
if (ret) {
pr_err("failed to start tdm stream\n");
goto out;
}
}
out:
mutex_unlock(&ts->lock);
return ret;
}
EXPORT_SYMBOL_GPL(axg_tdm_stream_start);
void axg_tdm_stream_stop(struct axg_tdm_stream *ts)
{
struct axg_tdm_formatter *formatter;
mutex_lock(&ts->lock);
ts->ready = false;
/* Stop all the formatters attached to the stream */
list_for_each_entry(formatter, &ts->formatter_list, list) {
axg_tdm_formatter_disable(formatter);
}
mutex_unlock(&ts->lock);
}
EXPORT_SYMBOL_GPL(axg_tdm_stream_stop);
struct axg_tdm_stream *axg_tdm_stream_alloc(struct axg_tdm_iface *iface)
{
struct axg_tdm_stream *ts;
ts = kzalloc(sizeof(*ts), GFP_KERNEL);
if (ts) {
INIT_LIST_HEAD(&ts->formatter_list);
mutex_init(&ts->lock);
ts->iface = iface;
}
return ts;
}
EXPORT_SYMBOL_GPL(axg_tdm_stream_alloc);
void axg_tdm_stream_free(struct axg_tdm_stream *ts)
{
/*
* If the list is not empty, it would mean that one of the formatter
* widget is still powered and attached to the interface while we
* are removing the TDM DAI. It should not be possible
*/
WARN_ON(!list_empty(&ts->formatter_list));
mutex_destroy(&ts->lock);
kfree(ts);
}
EXPORT_SYMBOL_GPL(axg_tdm_stream_free);
int axg_tdm_stream_set_cont_clocks(struct axg_tdm_stream *ts,
unsigned int fmt)
{
int ret = 0;
if (fmt & SND_SOC_DAIFMT_CONT) {
/* Clock are already enabled - skipping */
if (ts->clk_enabled)
return 0;
ret = clk_prepare_enable(ts->iface->mclk);
if (ret)
return ret;
ret = clk_prepare_enable(ts->iface->sclk);
if (ret)
goto err_sclk;
ret = clk_prepare_enable(ts->iface->lrclk);
if (ret)
goto err_lrclk;
ts->clk_enabled = true;
return 0;
}
/* Clocks are already disabled - skipping */
if (!ts->clk_enabled)
return 0;
clk_disable_unprepare(ts->iface->lrclk);
err_lrclk:
clk_disable_unprepare(ts->iface->sclk);
err_sclk:
clk_disable_unprepare(ts->iface->mclk);
ts->clk_enabled = false;
return ret;
}
EXPORT_SYMBOL_GPL(axg_tdm_stream_set_cont_clocks);
MODULE_DESCRIPTION("Amlogic AXG TDM formatter driver");
MODULE_AUTHOR("Jerome Brunet <[email protected]>");
MODULE_LICENSE("GPL v2");
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