mirror of https://github.com/hak5/openwrt.git
403 lines
12 KiB
Diff
403 lines
12 KiB
Diff
From c2b82810c0272bb29a9b426b017b196436957c76 Mon Sep 17 00:00:00 2001
|
|
From: Matthias Reichl <hias@horus.com>
|
|
Date: Sun, 7 May 2017 11:34:26 +0200
|
|
Subject: [PATCH 115/454] ASoC: bcm2835: Add support for TDM modes
|
|
|
|
bcm2835 supports arbitrary positioning of channel data within
|
|
a frame and thus is capable of supporting TDM modes. Since
|
|
the driver is limited to 2-channel operations only TDM setups
|
|
with exactly 2 active slots are supported.
|
|
|
|
Logical TDM slot numbering follows the usual convention:
|
|
|
|
For I2S-like modes, with a 50% duty-cycle frame clock,
|
|
slots 0, 2, ... are transmitted in the first half of a frame,
|
|
slots 1, 3, ... are transmitted in the second half.
|
|
|
|
For DSP modes slot numbering is ascending: 0, 1, 2, 3, ...
|
|
|
|
Channel position calculation has been refactored to use
|
|
TDM info and moved out of hw_params.
|
|
|
|
set_tdm_slot, set_bclk_ratio and hw_params now check more
|
|
strictly if the configuration is valid. Illegal configurations
|
|
like odd number of slots in I2S mode, data lengths exceeding
|
|
slot width or frame sizes larger than the hardware limit of
|
|
1024 are rejected. Also hw_params now properly checks for
|
|
errors from clk_set_rate.
|
|
|
|
Allowed PCM formats are already guarded by stream constraints,
|
|
thus the formats check in hw_params has been removed and
|
|
data_length is now retrieved via params_width().
|
|
|
|
Also standard functions like snd_soc_params_to_bclk are now
|
|
being used instead of manual calculations to make the code
|
|
more readable.
|
|
|
|
Special care has been taken to ensure that set_bclk_ratio works
|
|
as before. The bclk ratio is mapped to a 2-channel TDM config
|
|
with a slot width of half the ratio. In order to support odd ratios,
|
|
which can't be expressed via a TDM config, the ratio (frame length)
|
|
is stored and used by hw_params.
|
|
|
|
Signed-off-by: Matthias Reichl <hias@horus.com>
|
|
---
|
|
sound/soc/bcm/bcm2835-i2s.c | 243 ++++++++++++++++++++++++++++--------
|
|
1 file changed, 190 insertions(+), 53 deletions(-)
|
|
|
|
--- a/sound/soc/bcm/bcm2835-i2s.c
|
|
+++ b/sound/soc/bcm/bcm2835-i2s.c
|
|
@@ -31,6 +31,7 @@
|
|
* General Public License for more details.
|
|
*/
|
|
|
|
+#include <linux/bitops.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/device.h>
|
|
@@ -99,6 +100,8 @@
|
|
#define BCM2835_I2S_CHWID(v) (v)
|
|
#define BCM2835_I2S_CH1(v) ((v) << 16)
|
|
#define BCM2835_I2S_CH2(v) (v)
|
|
+#define BCM2835_I2S_CH1_POS(v) BCM2835_I2S_CH1(BCM2835_I2S_CHPOS(v))
|
|
+#define BCM2835_I2S_CH2_POS(v) BCM2835_I2S_CH2(BCM2835_I2S_CHPOS(v))
|
|
|
|
#define BCM2835_I2S_TX_PANIC(v) ((v) << 24)
|
|
#define BCM2835_I2S_RX_PANIC(v) ((v) << 16)
|
|
@@ -110,12 +113,19 @@
|
|
#define BCM2835_I2S_INT_RXR BIT(1)
|
|
#define BCM2835_I2S_INT_TXW BIT(0)
|
|
|
|
+/* Frame length register is 10 bit, maximum length 1024 */
|
|
+#define BCM2835_I2S_MAX_FRAME_LENGTH 1024
|
|
+
|
|
/* General device struct */
|
|
struct bcm2835_i2s_dev {
|
|
struct device *dev;
|
|
struct snd_dmaengine_dai_dma_data dma_data[2];
|
|
unsigned int fmt;
|
|
- unsigned int bclk_ratio;
|
|
+ unsigned int tdm_slots;
|
|
+ unsigned int rx_mask;
|
|
+ unsigned int tx_mask;
|
|
+ unsigned int slot_width;
|
|
+ unsigned int frame_length;
|
|
|
|
struct regmap *i2s_regmap;
|
|
struct clk *clk;
|
|
@@ -225,19 +235,117 @@ static int bcm2835_i2s_set_dai_bclk_rati
|
|
unsigned int ratio)
|
|
{
|
|
struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
|
|
- dev->bclk_ratio = ratio;
|
|
+
|
|
+ if (!ratio) {
|
|
+ dev->tdm_slots = 0;
|
|
+ return 0;
|
|
+ }
|
|
+
|
|
+ if (ratio > BCM2835_I2S_MAX_FRAME_LENGTH)
|
|
+ return -EINVAL;
|
|
+
|
|
+ dev->tdm_slots = 2;
|
|
+ dev->rx_mask = 0x03;
|
|
+ dev->tx_mask = 0x03;
|
|
+ dev->slot_width = ratio / 2;
|
|
+ dev->frame_length = ratio;
|
|
+
|
|
return 0;
|
|
}
|
|
|
|
+static int bcm2835_i2s_set_dai_tdm_slot(struct snd_soc_dai *dai,
|
|
+ unsigned int tx_mask, unsigned int rx_mask,
|
|
+ int slots, int width)
|
|
+{
|
|
+ struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
|
|
+
|
|
+ if (slots) {
|
|
+ if (slots < 0 || width < 0)
|
|
+ return -EINVAL;
|
|
+
|
|
+ /* Limit masks to available slots */
|
|
+ rx_mask &= GENMASK(slots - 1, 0);
|
|
+ tx_mask &= GENMASK(slots - 1, 0);
|
|
+
|
|
+ /*
|
|
+ * The driver is limited to 2-channel setups.
|
|
+ * Check that exactly 2 bits are set in the masks.
|
|
+ */
|
|
+ if (hweight_long((unsigned long) rx_mask) != 2
|
|
+ || hweight_long((unsigned long) tx_mask) != 2)
|
|
+ return -EINVAL;
|
|
+
|
|
+ if (slots * width > BCM2835_I2S_MAX_FRAME_LENGTH)
|
|
+ return -EINVAL;
|
|
+ }
|
|
+
|
|
+ dev->tdm_slots = slots;
|
|
+
|
|
+ dev->rx_mask = rx_mask;
|
|
+ dev->tx_mask = tx_mask;
|
|
+ dev->slot_width = width;
|
|
+ dev->frame_length = slots * width;
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+/*
|
|
+ * Convert logical slot number into physical slot number.
|
|
+ *
|
|
+ * If odd_offset is 0 sequential number is identical to logical number.
|
|
+ * This is used for DSP modes with slot numbering 0 1 2 3 ...
|
|
+ *
|
|
+ * Otherwise odd_offset defines the physical offset for odd numbered
|
|
+ * slots. This is used for I2S and left/right justified modes to
|
|
+ * translate from logical slot numbers 0 1 2 3 ... into physical slot
|
|
+ * numbers 0 2 ... 3 4 ...
|
|
+ */
|
|
+static int bcm2835_i2s_convert_slot(unsigned int slot, unsigned int odd_offset)
|
|
+{
|
|
+ if (!odd_offset)
|
|
+ return slot;
|
|
+
|
|
+ if (slot & 1)
|
|
+ return (slot >> 1) + odd_offset;
|
|
+
|
|
+ return slot >> 1;
|
|
+}
|
|
+
|
|
+/*
|
|
+ * Calculate channel position from mask and slot width.
|
|
+ *
|
|
+ * Mask must contain exactly 2 set bits.
|
|
+ * Lowest set bit is channel 1 position, highest set bit channel 2.
|
|
+ * The constant offset is added to both channel positions.
|
|
+ *
|
|
+ * If odd_offset is > 0 slot positions are translated to
|
|
+ * I2S-style TDM slot numbering ( 0 2 ... 3 4 ...) with odd
|
|
+ * logical slot numbers starting at physical slot odd_offset.
|
|
+ */
|
|
+static void bcm2835_i2s_calc_channel_pos(
|
|
+ unsigned int *ch1_pos, unsigned int *ch2_pos,
|
|
+ unsigned int mask, unsigned int width,
|
|
+ unsigned int bit_offset, unsigned int odd_offset)
|
|
+{
|
|
+ *ch1_pos = bcm2835_i2s_convert_slot((ffs(mask) - 1), odd_offset)
|
|
+ * width + bit_offset;
|
|
+ *ch2_pos = bcm2835_i2s_convert_slot((fls(mask) - 1), odd_offset)
|
|
+ * width + bit_offset;
|
|
+}
|
|
+
|
|
static int bcm2835_i2s_hw_params(struct snd_pcm_substream *substream,
|
|
struct snd_pcm_hw_params *params,
|
|
struct snd_soc_dai *dai)
|
|
{
|
|
struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
|
|
- unsigned int sampling_rate = params_rate(params);
|
|
- unsigned int data_length, data_delay, bclk_ratio;
|
|
- unsigned int ch1pos, ch2pos, mode, format;
|
|
+ unsigned int data_length, data_delay, framesync_length;
|
|
+ unsigned int slots, slot_width, odd_slot_offset;
|
|
+ int frame_length, bclk_rate;
|
|
+ unsigned int rx_mask, tx_mask;
|
|
+ unsigned int rx_ch1_pos, rx_ch2_pos, tx_ch1_pos, tx_ch2_pos;
|
|
+ unsigned int mode, format;
|
|
uint32_t csreg;
|
|
+ int ret = 0;
|
|
|
|
/*
|
|
* If a stream is already enabled,
|
|
@@ -248,39 +356,44 @@ static int bcm2835_i2s_hw_params(struct
|
|
if (csreg & (BCM2835_I2S_TXON | BCM2835_I2S_RXON))
|
|
return 0;
|
|
|
|
- /*
|
|
- * Adjust the data length according to the format.
|
|
- * We prefill the half frame length with an integer
|
|
- * divider of 2400 as explained at the clock settings.
|
|
- * Maybe it is overwritten there, if the Integer mode
|
|
- * does not apply.
|
|
- */
|
|
- switch (params_format(params)) {
|
|
- case SNDRV_PCM_FORMAT_S16_LE:
|
|
- data_length = 16;
|
|
- break;
|
|
- case SNDRV_PCM_FORMAT_S24_LE:
|
|
- data_length = 24;
|
|
- break;
|
|
- case SNDRV_PCM_FORMAT_S32_LE:
|
|
- data_length = 32;
|
|
- break;
|
|
- default:
|
|
- return -EINVAL;
|
|
+ data_length = params_width(params);
|
|
+ data_delay = 0;
|
|
+ odd_slot_offset = 0;
|
|
+ mode = 0;
|
|
+
|
|
+ if (dev->tdm_slots) {
|
|
+ slots = dev->tdm_slots;
|
|
+ slot_width = dev->slot_width;
|
|
+ frame_length = dev->frame_length;
|
|
+ rx_mask = dev->rx_mask;
|
|
+ tx_mask = dev->tx_mask;
|
|
+ bclk_rate = dev->frame_length * params_rate(params);
|
|
+ } else {
|
|
+ slots = 2;
|
|
+ slot_width = params_width(params);
|
|
+ rx_mask = 0x03;
|
|
+ tx_mask = 0x03;
|
|
+
|
|
+ frame_length = snd_soc_params_to_frame_size(params);
|
|
+ if (frame_length < 0)
|
|
+ return frame_length;
|
|
+
|
|
+ bclk_rate = snd_soc_params_to_bclk(params);
|
|
+ if (bclk_rate < 0)
|
|
+ return bclk_rate;
|
|
}
|
|
|
|
- /* If bclk_ratio already set, use that one. */
|
|
- if (dev->bclk_ratio)
|
|
- bclk_ratio = dev->bclk_ratio;
|
|
- else
|
|
- /* otherwise calculate a fitting block ratio */
|
|
- bclk_ratio = 2 * data_length;
|
|
+ /* Check if data fits into slots */
|
|
+ if (data_length > slot_width)
|
|
+ return -EINVAL;
|
|
|
|
/* Clock should only be set up here if CPU is clock master */
|
|
switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
|
|
case SND_SOC_DAIFMT_CBS_CFS:
|
|
case SND_SOC_DAIFMT_CBS_CFM:
|
|
- clk_set_rate(dev->clk, sampling_rate * bclk_ratio);
|
|
+ ret = clk_set_rate(dev->clk, bclk_rate);
|
|
+ if (ret)
|
|
+ return ret;
|
|
break;
|
|
default:
|
|
break;
|
|
@@ -294,9 +407,26 @@ static int bcm2835_i2s_hw_params(struct
|
|
|
|
format |= BCM2835_I2S_CHWID((data_length-8)&0xf);
|
|
|
|
+ /* CH2 format is the same as for CH1 */
|
|
+ format = BCM2835_I2S_CH1(format) | BCM2835_I2S_CH2(format);
|
|
+
|
|
switch (dev->fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
|
|
case SND_SOC_DAIFMT_I2S:
|
|
+ /* I2S mode needs an even number of slots */
|
|
+ if (slots & 1)
|
|
+ return -EINVAL;
|
|
+
|
|
+ /*
|
|
+ * Use I2S-style logical slot numbering: even slots
|
|
+ * are in first half of frame, odd slots in second half.
|
|
+ */
|
|
+ odd_slot_offset = slots >> 1;
|
|
+
|
|
+ /* MSB starts one cycle after frame start */
|
|
data_delay = 1;
|
|
+
|
|
+ /* Setup frame sync signal for 50% duty cycle */
|
|
+ framesync_length = frame_length / 2;
|
|
break;
|
|
default:
|
|
/*
|
|
@@ -307,19 +437,10 @@ static int bcm2835_i2s_hw_params(struct
|
|
return -EINVAL;
|
|
}
|
|
|
|
- ch1pos = data_delay;
|
|
- ch2pos = bclk_ratio / 2 + data_delay;
|
|
-
|
|
- switch (params_channels(params)) {
|
|
- case 2:
|
|
- case 8:
|
|
- format = BCM2835_I2S_CH1(format) | BCM2835_I2S_CH2(format);
|
|
- format |= BCM2835_I2S_CH1(BCM2835_I2S_CHPOS(ch1pos));
|
|
- format |= BCM2835_I2S_CH2(BCM2835_I2S_CHPOS(ch2pos));
|
|
- break;
|
|
- default:
|
|
- return -EINVAL;
|
|
- }
|
|
+ bcm2835_i2s_calc_channel_pos(&rx_ch1_pos, &rx_ch2_pos,
|
|
+ rx_mask, slot_width, data_delay, odd_slot_offset);
|
|
+ bcm2835_i2s_calc_channel_pos(&tx_ch1_pos, &tx_ch2_pos,
|
|
+ tx_mask, slot_width, data_delay, odd_slot_offset);
|
|
|
|
/*
|
|
* Set format for both streams.
|
|
@@ -327,11 +448,16 @@ static int bcm2835_i2s_hw_params(struct
|
|
* (and therefore word length) anyway,
|
|
* so the format will be the same.
|
|
*/
|
|
- regmap_write(dev->i2s_regmap, BCM2835_I2S_RXC_A_REG, format);
|
|
- regmap_write(dev->i2s_regmap, BCM2835_I2S_TXC_A_REG, format);
|
|
+ regmap_write(dev->i2s_regmap, BCM2835_I2S_RXC_A_REG,
|
|
+ format
|
|
+ | BCM2835_I2S_CH1_POS(rx_ch1_pos)
|
|
+ | BCM2835_I2S_CH2_POS(rx_ch2_pos));
|
|
+ regmap_write(dev->i2s_regmap, BCM2835_I2S_TXC_A_REG,
|
|
+ format
|
|
+ | BCM2835_I2S_CH1_POS(tx_ch1_pos)
|
|
+ | BCM2835_I2S_CH2_POS(tx_ch2_pos));
|
|
|
|
/* Setup the I2S mode */
|
|
- mode = 0;
|
|
|
|
if (data_length <= 16) {
|
|
/*
|
|
@@ -343,8 +469,8 @@ static int bcm2835_i2s_hw_params(struct
|
|
mode |= BCM2835_I2S_FTXP | BCM2835_I2S_FRXP;
|
|
}
|
|
|
|
- mode |= BCM2835_I2S_FLEN(bclk_ratio - 1);
|
|
- mode |= BCM2835_I2S_FSLEN(bclk_ratio / 2);
|
|
+ mode |= BCM2835_I2S_FLEN(frame_length - 1);
|
|
+ mode |= BCM2835_I2S_FSLEN(framesync_length);
|
|
|
|
/* Master or slave? */
|
|
switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
|
|
@@ -424,7 +550,20 @@ static int bcm2835_i2s_hw_params(struct
|
|
/* Clear FIFOs */
|
|
bcm2835_i2s_clear_fifos(dev, true, true);
|
|
|
|
- return 0;
|
|
+ dev_dbg(dev->dev,
|
|
+ "slots: %d width: %d rx mask: 0x%02x tx_mask: 0x%02x\n",
|
|
+ slots, slot_width, rx_mask, tx_mask);
|
|
+
|
|
+ dev_dbg(dev->dev, "frame len: %d sync len: %d data len: %d\n",
|
|
+ frame_length, framesync_length, data_length);
|
|
+
|
|
+ dev_dbg(dev->dev, "rx pos: %d,%d tx pos: %d,%d\n",
|
|
+ rx_ch1_pos, rx_ch2_pos, tx_ch1_pos, tx_ch2_pos);
|
|
+
|
|
+ dev_dbg(dev->dev, "sampling rate: %d bclk rate: %d\n",
|
|
+ params_rate(params), bclk_rate);
|
|
+
|
|
+ return ret;
|
|
}
|
|
|
|
static int bcm2835_i2s_prepare(struct snd_pcm_substream *substream,
|
|
@@ -560,6 +699,7 @@ static const struct snd_soc_dai_ops bcm2
|
|
.hw_params = bcm2835_i2s_hw_params,
|
|
.set_fmt = bcm2835_i2s_set_dai_fmt,
|
|
.set_bclk_ratio = bcm2835_i2s_set_dai_bclk_ratio,
|
|
+ .set_tdm_slot = bcm2835_i2s_set_dai_tdm_slot,
|
|
};
|
|
|
|
static int bcm2835_i2s_dai_probe(struct snd_soc_dai *dai)
|
|
@@ -700,9 +840,6 @@ static int bcm2835_i2s_probe(struct plat
|
|
dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].flags =
|
|
SND_DMAENGINE_PCM_DAI_FLAG_PACK;
|
|
|
|
- /* BCLK ratio - use default */
|
|
- dev->bclk_ratio = 0;
|
|
-
|
|
/* Store the pdev */
|
|
dev->dev = &pdev->dev;
|
|
dev_set_drvdata(&pdev->dev, dev);
|