Merge series "ASoC: stm32: i2s: add master clock provider" from Olivier Moysan <olivier.moysan@foss.st.com>:

Add master clock generation support in STM32 I2S driver.
Resend of patch https://lkml.org/lkml/2020/9/11/264

Olivier Moysan (2):
  ASoC: dt-bindings: add mclk provider support to stm32 i2s
  ASoC: stm32: i2s: add master clock provider

 .../bindings/sound/st,stm32-i2s.yaml          |   4 +
 sound/soc/stm/stm32_i2s.c                     | 310 +++++++++++++++---
 2 files changed, 270 insertions(+), 44 deletions(-)

--
2.17.1
This commit is contained in:
Mark Brown 2021-02-05 16:42:34 +00:00
commit b6040f9b98
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
2 changed files with 270 additions and 44 deletions

View File

@ -54,6 +54,10 @@ properties:
resets:
maxItems: 1
"#clock-cells":
description: Configure the I2S device as MCLK clock provider.
const: 0
required:
- compatible
- "#sound-dai-cells"

View File

@ -8,6 +8,7 @@
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/of_irq.h>
@ -196,6 +197,9 @@ enum i2s_datlen {
#define STM32_I2S_IS_MASTER(x) ((x)->ms_flg == I2S_MS_MASTER)
#define STM32_I2S_IS_SLAVE(x) ((x)->ms_flg == I2S_MS_SLAVE)
#define STM32_I2S_NAME_LEN 32
#define STM32_I2S_RATE_11K 11025
/**
* struct stm32_i2s_data - private data of I2S
* @regmap_conf: I2S register map configuration pointer
@ -206,6 +210,7 @@ enum i2s_datlen {
* @dma_data_rx: dma configuration data for tx channel
* @substream: PCM substream data pointer
* @i2sclk: kernel clock feeding the I2S clock generator
* @i2smclk: master clock from I2S mclk provider
* @pclk: peripheral clock driving bus interface
* @x8kclk: I2S parent clock for sampling frequencies multiple of 8kHz
* @x11kclk: I2S parent clock for sampling frequencies multiple of 11kHz
@ -215,6 +220,9 @@ enum i2s_datlen {
* @irq_lock: prevent race condition with IRQ
* @mclk_rate: master clock frequency (Hz)
* @fmt: DAI protocol
* @divider: prescaler division ratio
* @div: prescaler div field
* @odd: prescaler odd field
* @refcount: keep count of opened streams on I2S
* @ms_flg: master mode flag.
*/
@ -227,6 +235,7 @@ struct stm32_i2s_data {
struct snd_dmaengine_dai_dma_data dma_data_rx;
struct snd_pcm_substream *substream;
struct clk *i2sclk;
struct clk *i2smclk;
struct clk *pclk;
struct clk *x8kclk;
struct clk *x11kclk;
@ -236,10 +245,210 @@ struct stm32_i2s_data {
spinlock_t irq_lock; /* used to prevent race condition with IRQ */
unsigned int mclk_rate;
unsigned int fmt;
unsigned int divider;
unsigned int div;
bool odd;
int refcount;
int ms_flg;
};
struct stm32_i2smclk_data {
struct clk_hw hw;
unsigned long freq;
struct stm32_i2s_data *i2s_data;
};
#define to_mclk_data(_hw) container_of(_hw, struct stm32_i2smclk_data, hw)
static int stm32_i2s_calc_clk_div(struct stm32_i2s_data *i2s,
unsigned long input_rate,
unsigned long output_rate)
{
unsigned int ratio, div, divider = 1;
bool odd;
ratio = DIV_ROUND_CLOSEST(input_rate, output_rate);
/* Check the parity of the divider */
odd = ratio & 0x1;
/* Compute the div prescaler */
div = ratio >> 1;
/* If div is 0 actual divider is 1 */
if (div) {
divider = ((2 * div) + odd);
dev_dbg(&i2s->pdev->dev, "Divider: 2*%d(div)+%d(odd) = %d\n",
div, odd, divider);
}
/* Division by three is not allowed by I2S prescaler */
if ((div == 1 && odd) || div > I2S_CGFR_I2SDIV_MAX) {
dev_err(&i2s->pdev->dev, "Wrong divider setting\n");
return -EINVAL;
}
if (input_rate % divider)
dev_dbg(&i2s->pdev->dev,
"Rate not accurate. requested (%ld), actual (%ld)\n",
output_rate, input_rate / divider);
i2s->div = div;
i2s->odd = odd;
i2s->divider = divider;
return 0;
}
static int stm32_i2s_set_clk_div(struct stm32_i2s_data *i2s)
{
u32 cgfr, cgfr_mask;
cgfr = I2S_CGFR_I2SDIV_SET(i2s->div) | (i2s->odd << I2S_CGFR_ODD_SHIFT);
cgfr_mask = I2S_CGFR_I2SDIV_MASK | I2S_CGFR_ODD;
return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
cgfr_mask, cgfr);
}
static int stm32_i2s_set_parent_clock(struct stm32_i2s_data *i2s,
unsigned int rate)
{
struct platform_device *pdev = i2s->pdev;
struct clk *parent_clk;
int ret;
if (!(rate % STM32_I2S_RATE_11K))
parent_clk = i2s->x11kclk;
else
parent_clk = i2s->x8kclk;
ret = clk_set_parent(i2s->i2sclk, parent_clk);
if (ret)
dev_err(&pdev->dev,
"Error %d setting i2sclk parent clock\n", ret);
return ret;
}
static long stm32_i2smclk_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
struct stm32_i2s_data *i2s = mclk->i2s_data;
int ret;
ret = stm32_i2s_calc_clk_div(i2s, *prate, rate);
if (ret)
return ret;
mclk->freq = *prate / i2s->divider;
return mclk->freq;
}
static unsigned long stm32_i2smclk_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
return mclk->freq;
}
static int stm32_i2smclk_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
struct stm32_i2s_data *i2s = mclk->i2s_data;
int ret;
ret = stm32_i2s_calc_clk_div(i2s, parent_rate, rate);
if (ret)
return ret;
ret = stm32_i2s_set_clk_div(i2s);
if (ret)
return ret;
mclk->freq = rate;
return 0;
}
static int stm32_i2smclk_enable(struct clk_hw *hw)
{
struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
struct stm32_i2s_data *i2s = mclk->i2s_data;
dev_dbg(&i2s->pdev->dev, "Enable master clock\n");
return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
}
static void stm32_i2smclk_disable(struct clk_hw *hw)
{
struct stm32_i2smclk_data *mclk = to_mclk_data(hw);
struct stm32_i2s_data *i2s = mclk->i2s_data;
dev_dbg(&i2s->pdev->dev, "Disable master clock\n");
regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG, I2S_CGFR_MCKOE, 0);
}
static const struct clk_ops mclk_ops = {
.enable = stm32_i2smclk_enable,
.disable = stm32_i2smclk_disable,
.recalc_rate = stm32_i2smclk_recalc_rate,
.round_rate = stm32_i2smclk_round_rate,
.set_rate = stm32_i2smclk_set_rate,
};
static int stm32_i2s_add_mclk_provider(struct stm32_i2s_data *i2s)
{
struct clk_hw *hw;
struct stm32_i2smclk_data *mclk;
struct device *dev = &i2s->pdev->dev;
const char *pname = __clk_get_name(i2s->i2sclk);
char *mclk_name, *p, *s = (char *)pname;
int ret, i = 0;
mclk = devm_kzalloc(dev, sizeof(*mclk), GFP_KERNEL);
if (!mclk)
return -ENOMEM;
mclk_name = devm_kcalloc(dev, sizeof(char),
STM32_I2S_NAME_LEN, GFP_KERNEL);
if (!mclk_name)
return -ENOMEM;
/*
* Forge mclk clock name from parent clock name and suffix.
* String after "_" char is stripped in parent name.
*/
p = mclk_name;
while (*s && *s != '_' && (i < (STM32_I2S_NAME_LEN - 7))) {
*p++ = *s++;
i++;
}
strcat(p, "_mclk");
mclk->hw.init = CLK_HW_INIT(mclk_name, pname, &mclk_ops, 0);
mclk->i2s_data = i2s;
hw = &mclk->hw;
dev_dbg(dev, "Register master clock %s\n", mclk_name);
ret = devm_clk_hw_register(&i2s->pdev->dev, hw);
if (ret) {
dev_err(dev, "mclk register fails with error %d\n", ret);
return ret;
}
i2s->i2smclk = hw->clk;
/* register mclk provider */
return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw);
}
static irqreturn_t stm32_i2s_isr(int irq, void *devid)
{
struct stm32_i2s_data *i2s = (struct stm32_i2s_data *)devid;
@ -405,18 +614,46 @@ static int stm32_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
int clk_id, unsigned int freq, int dir)
{
struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
int ret = 0;
dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz\n", freq);
dev_dbg(cpu_dai->dev, "I2S MCLK frequency is %uHz. mode: %s, dir: %s\n",
freq, STM32_I2S_IS_MASTER(i2s) ? "master" : "slave",
dir ? "output" : "input");
if ((dir == SND_SOC_CLOCK_OUT) && STM32_I2S_IS_MASTER(i2s)) {
i2s->mclk_rate = freq;
/* Enable master clock if master mode and mclk-fs are set */
return regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
/* MCLK generation is available only in master mode */
if (dir == SND_SOC_CLOCK_OUT && STM32_I2S_IS_MASTER(i2s)) {
if (!i2s->i2smclk) {
dev_dbg(cpu_dai->dev, "No MCLK registered\n");
return 0;
}
return 0;
/* Assume shutdown if requested frequency is 0Hz */
if (!freq) {
/* Release mclk rate only if rate was actually set */
if (i2s->mclk_rate) {
clk_rate_exclusive_put(i2s->i2smclk);
i2s->mclk_rate = 0;
}
return regmap_update_bits(i2s->regmap,
STM32_I2S_CGFR_REG,
I2S_CGFR_MCKOE, 0);
}
/* If master clock is used, set parent clock now */
ret = stm32_i2s_set_parent_clock(i2s, freq);
if (ret)
return ret;
ret = clk_set_rate_exclusive(i2s->i2smclk, freq);
if (ret) {
dev_err(cpu_dai->dev, "Could not set mclk rate\n");
return ret;
}
ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
I2S_CGFR_MCKOE, I2S_CGFR_MCKOE);
if (!ret)
i2s->mclk_rate = freq;
}
return ret;
}
static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
@ -424,11 +661,10 @@ static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
{
struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
unsigned long i2s_clock_rate;
unsigned int tmp, div, real_div, nb_bits, frame_len;
unsigned int nb_bits, frame_len;
unsigned int rate = params_rate(params);
u32 cgfr;
int ret;
u32 cgfr, cgfr_mask;
bool odd;
if (!(rate % 11025))
clk_set_parent(i2s->i2sclk, i2s->x11kclk);
@ -449,7 +685,10 @@ static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
* dsp mode : div = i2s_clk / (nb_bits x ws)
*/
if (i2s->mclk_rate) {
tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, i2s->mclk_rate);
ret = stm32_i2s_calc_clk_div(i2s, i2s_clock_rate,
i2s->mclk_rate);
if (ret)
return ret;
} else {
frame_len = 32;
if ((i2s->fmt & SND_SOC_DAIFMT_FORMAT_MASK) ==
@ -462,34 +701,13 @@ static int stm32_i2s_configure_clock(struct snd_soc_dai *cpu_dai,
return ret;
nb_bits = frame_len * ((cgfr & I2S_CGFR_CHLEN) + 1);
tmp = DIV_ROUND_CLOSEST(i2s_clock_rate, (nb_bits * rate));
ret = stm32_i2s_calc_clk_div(i2s, i2s_clock_rate,
(nb_bits * rate));
if (ret)
return ret;
}
/* Check the parity of the divider */
odd = tmp & 0x1;
/* Compute the div prescaler */
div = tmp >> 1;
cgfr = I2S_CGFR_I2SDIV_SET(div) | (odd << I2S_CGFR_ODD_SHIFT);
cgfr_mask = I2S_CGFR_I2SDIV_MASK | I2S_CGFR_ODD;
real_div = ((2 * div) + odd);
dev_dbg(cpu_dai->dev, "I2S clk: %ld, SCLK: %d\n",
i2s_clock_rate, rate);
dev_dbg(cpu_dai->dev, "Divider: 2*%d(div)+%d(odd) = %d\n",
div, odd, real_div);
if (((div == 1) && odd) || (div > I2S_CGFR_I2SDIV_MAX)) {
dev_err(cpu_dai->dev, "Wrong divider setting\n");
return -EINVAL;
}
if (!div && !odd)
dev_warn(cpu_dai->dev, "real divider forced to 1\n");
ret = regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
cgfr_mask, cgfr);
ret = stm32_i2s_set_clk_div(i2s);
if (ret < 0)
return ret;
@ -694,9 +912,6 @@ static void stm32_i2s_shutdown(struct snd_pcm_substream *substream,
struct stm32_i2s_data *i2s = snd_soc_dai_get_drvdata(cpu_dai);
unsigned long flags;
regmap_update_bits(i2s->regmap, STM32_I2S_CGFR_REG,
I2S_CGFR_MCKOE, (unsigned int)~I2S_CGFR_MCKOE);
clk_disable_unprepare(i2s->i2sclk);
spin_lock_irqsave(&i2s->irq_lock, flags);
@ -861,6 +1076,13 @@ static int stm32_i2s_parse_dt(struct platform_device *pdev,
return PTR_ERR(i2s->x11kclk);
}
/* Register mclk provider if requested */
if (of_find_property(np, "#clock-cells", NULL)) {
ret = stm32_i2s_add_mclk_provider(i2s);
if (ret < 0)
return ret;
}
/* Get irqs */
irq = platform_get_irq(pdev, 0);
if (irq < 0)
@ -906,16 +1128,16 @@ static int stm32_i2s_probe(struct platform_device *pdev)
if (!i2s)
return -ENOMEM;
ret = stm32_i2s_parse_dt(pdev, i2s);
if (ret)
return ret;
i2s->pdev = pdev;
i2s->ms_flg = I2S_MS_NOT_SET;
spin_lock_init(&i2s->lock_fd);
spin_lock_init(&i2s->irq_lock);
platform_set_drvdata(pdev, i2s);
ret = stm32_i2s_parse_dt(pdev, i2s);
if (ret)
return ret;
ret = stm32_i2s_dais_init(pdev, i2s);
if (ret)
return ret;