u-boot/drivers/sound/tegra_i2s.c
Simon Glass c5a120b3f0 tegra: sound: Add an I2S driver
Add a driver which supports transmitting digital sound to an audio codec.
This uses fixed parameters as a device-tree binding is not currently
defined.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2019-05-24 10:14:03 -07:00

124 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2018 Google LLC
* Written by Simon Glass <sjg@chromium.org>
*/
#define LOG_CATEGORY UCLASS_I2S
#define LOG_DEBUG
#include <common.h>
#include <dm.h>
#include <i2s.h>
#include <misc.h>
#include <sound.h>
#include <asm/io.h>
#include <asm/arch-tegra/tegra_i2s.h>
#include "tegra_i2s_priv.h"
int tegra_i2s_set_cif_tx_ctrl(struct udevice *dev, u32 value)
{
struct i2s_uc_priv *priv = dev_get_uclass_priv(dev);
struct i2s_ctlr *regs = (struct i2s_ctlr *)priv->base_address;
writel(value, &regs->cif_tx_ctrl);
return 0;
}
static void tegra_i2s_transmit_enable(struct i2s_ctlr *regs, int on)
{
clrsetbits_le32(&regs->ctrl, I2S_CTRL_XFER_EN_TX,
on ? I2S_CTRL_XFER_EN_TX : 0);
}
static int i2s_tx_init(struct i2s_uc_priv *pi2s_tx)
{
struct i2s_ctlr *regs = (struct i2s_ctlr *)pi2s_tx->base_address;
u32 audio_bits = (pi2s_tx->bitspersample >> 2) - 1;
u32 ctrl = readl(&regs->ctrl);
/* Set format to LRCK / Left Low */
ctrl &= ~(I2S_CTRL_FRAME_FORMAT_MASK | I2S_CTRL_LRCK_MASK);
ctrl |= I2S_CTRL_FRAME_FORMAT_LRCK;
ctrl |= I2S_CTRL_LRCK_L_LOW;
/* Disable all transmission until we are ready to transfer */
ctrl &= ~(I2S_CTRL_XFER_EN_TX | I2S_CTRL_XFER_EN_RX);
/* Serve as master */
ctrl |= I2S_CTRL_MASTER_ENABLE;
/* Configure audio bits size */
ctrl &= ~I2S_CTRL_BIT_SIZE_MASK;
ctrl |= audio_bits << I2S_CTRL_BIT_SIZE_SHIFT;
writel(ctrl, &regs->ctrl);
/* Timing in LRCK mode: */
writel(pi2s_tx->bitspersample, &regs->timing);
/* I2S mode has [TX/RX]_DATA_OFFSET both set to 1 */
writel(((1 << I2S_OFFSET_RX_DATA_OFFSET_SHIFT) |
(1 << I2S_OFFSET_TX_DATA_OFFSET_SHIFT)), &regs->offset);
/* FSYNC_WIDTH = 2 clocks wide, TOTAL_SLOTS = 2 slots per fsync */
writel((2 - 1) << I2S_CH_CTRL_FSYNC_WIDTH_SHIFT, &regs->ch_ctrl);
return 0;
}
static int tegra_i2s_tx_data(struct udevice *dev, void *data, uint data_size)
{
struct i2s_uc_priv *priv = dev_get_uclass_priv(dev);
struct i2s_ctlr *regs = (struct i2s_ctlr *)priv->base_address;
int ret;
tegra_i2s_transmit_enable(regs, 1);
ret = misc_write(dev_get_parent(dev), 0, data, data_size);
tegra_i2s_transmit_enable(regs, 0);
if (ret < 0)
return ret;
else if (ret < data_size)
return -EIO;
return 0;
}
static int tegra_i2s_probe(struct udevice *dev)
{
struct i2s_uc_priv *priv = dev_get_uclass_priv(dev);
ulong base;
base = dev_read_addr(dev);
if (base == FDT_ADDR_T_NONE) {
debug("%s: Missing i2s base\n", __func__);
return -EINVAL;
}
priv->base_address = base;
priv->id = 1;
priv->audio_pll_clk = 4800000;
priv->samplingrate = 48000;
priv->bitspersample = 16;
priv->channels = 2;
priv->rfs = 256;
priv->bfs = 32;
return i2s_tx_init(priv);
}
static const struct i2s_ops tegra_i2s_ops = {
.tx_data = tegra_i2s_tx_data,
};
static const struct udevice_id tegra_i2s_ids[] = {
{ .compatible = "nvidia,tegra124-i2s" },
{ }
};
U_BOOT_DRIVER(tegra_i2s) = {
.name = "tegra_i2s",
.id = UCLASS_I2S,
.of_match = tegra_i2s_ids,
.probe = tegra_i2s_probe,
.ops = &tegra_i2s_ops,
};