u-boot/drivers/sound/rockchip_i2s.c
Simon Glass 2665f09115 rockchip: Add an I2S driver
Add a driver for I2S which allows audio data to be sent from the SoC to
the audio codec. The sample rate and other settings are hard-coded for now
as there is no suitable device-tree binding available.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
2019-02-01 16:59:10 +01:00

150 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2018 Google LLC
* Copyright 2014 Rockchip Electronics Co., Ltd.
* Taken from dc i2s/rockchip.c
*/
#define LOG_CATEGORY UCLASS_I2S
#include <common.h>
#include <dm.h>
#include <i2s.h>
#include <sound.h>
#include <asm/io.h>
struct rk_i2s_regs {
u32 txcr; /* I2S_TXCR, 0x00 */
u32 rxcr; /* I2S_RXCR, 0x04 */
u32 ckr; /* I2S_CKR, 0x08 */
u32 fifolr; /* I2S_FIFOLR, 0x0C */
u32 dmacr; /* I2S_DMACR, 0x10 */
u32 intcr; /* I2S_INTCR, 0x14 */
u32 intsr; /* I2S_INTSR, 0x18 */
u32 xfer; /* I2S_XFER, 0x1C */
u32 clr; /* I2S_CLR, 0x20 */
u32 txdr; /* I2S_TXDR, 0x24 */
u32 rxdr; /* I2S_RXDR, 0x28 */
};
enum {
/* I2S_XFER */
I2S_RX_TRAN_BIT = BIT(1),
I2S_TX_TRAN_BIT = BIT(0),
I2S_TRAN_MASK = 3 << 0,
/* I2S_TXCKR */
I2S_MCLK_DIV_SHIFT = 16,
I2S_MCLK_DIV_MASK = (0xff << I2S_MCLK_DIV_SHIFT),
I2S_RX_SCLK_DIV_SHIFT = 8,
I2S_RX_SCLK_DIV_MASK = 0xff << I2S_RX_SCLK_DIV_SHIFT,
I2S_TX_SCLK_DIV_SHIFT = 0,
I2S_TX_SCLK_DIV_MASK = 0xff << I2S_TX_SCLK_DIV_SHIFT,
I2S_DATA_WIDTH_SHIFT = 0,
I2S_DATA_WIDTH_MASK = 0x1f << I2S_DATA_WIDTH_SHIFT,
};
static int rockchip_i2s_init(struct i2s_uc_priv *priv)
{
struct rk_i2s_regs *regs = (struct rk_i2s_regs *)priv->base_address;
u32 bps = priv->bitspersample;
u32 lrf = priv->rfs;
u32 chn = priv->channels;
u32 mode = 0;
clrbits_le32(&regs->xfer, I2S_TX_TRAN_BIT);
mode = readl(&regs->txcr) & ~0x1f;
switch (priv->bitspersample) {
case 16:
case 24:
mode |= (priv->bitspersample - 1) << I2S_DATA_WIDTH_SHIFT;
break;
default:
log_err("Invalid sample size input %d\n", priv->bitspersample);
return -EINVAL;
}
writel(mode, &regs->txcr);
mode = readl(&regs->ckr) & ~I2S_MCLK_DIV_MASK;
mode |= (lrf / (bps * chn) - 1) << I2S_MCLK_DIV_SHIFT;
mode &= ~I2S_TX_SCLK_DIV_MASK;
mode |= (priv->bitspersample * priv->channels - 1) <<
I2S_TX_SCLK_DIV_SHIFT;
writel(mode, &regs->ckr);
return 0;
}
static int i2s_send_data(struct rk_i2s_regs *regs, u32 *data, uint length)
{
for (int i = 0; i < min(32u, length); i++)
writel(*data++, &regs->txdr);
length -= min(32u, length);
/* enable both tx and rx */
setbits_le32(&regs->xfer, I2S_TRAN_MASK);
while (length) {
if ((readl(&regs->fifolr) & 0x3f) < 0x20) {
writel(*data++, &regs->txdr);
length--;
}
}
while (readl(&regs->fifolr) & 0x3f)
/* wait until FIFO empty */;
clrbits_le32(&regs->xfer, I2S_TRAN_MASK);
writel(0, &regs->clr);
return 0;
}
static int rockchip_i2s_tx_data(struct udevice *dev, void *data, uint data_size)
{
struct i2s_uc_priv *priv = dev_get_uclass_priv(dev);
struct rk_i2s_regs *regs = (struct rk_i2s_regs *)priv->base_address;
return i2s_send_data(regs, data, data_size / sizeof(u32));
}
static int rockchip_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) {
log_debug("Missing i2s base\n");
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 rockchip_i2s_init(priv);
}
static const struct i2s_ops rockchip_i2s_ops = {
.tx_data = rockchip_i2s_tx_data,
};
static const struct udevice_id rockchip_i2s_ids[] = {
{ .compatible = "rockchip,rk3288-i2s" },
{ }
};
U_BOOT_DRIVER(rockchip_i2s) = {
.name = "rockchip_i2s",
.id = UCLASS_I2S,
.of_match = rockchip_i2s_ids,
.probe = rockchip_i2s_probe,
.ops = &rockchip_i2s_ops,
};