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-rw-r--r--target/linux/brcm2708/patches-3.10/0116-ASoC-Add-support-for-BCM2708.patch1007
1 files changed, 1007 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-3.10/0116-ASoC-Add-support-for-BCM2708.patch b/target/linux/brcm2708/patches-3.10/0116-ASoC-Add-support-for-BCM2708.patch
new file mode 100644
index 0000000..28a801a
--- /dev/null
+++ b/target/linux/brcm2708/patches-3.10/0116-ASoC-Add-support-for-BCM2708.patch
@@ -0,0 +1,1007 @@
+From f3c21ba6458e497638d4a006645f055b63288168 Mon Sep 17 00:00:00 2001
+From: Florian Meier <florian.meier@koalo.de>
+Date: Fri, 22 Nov 2013 14:33:38 +0100
+Subject: [PATCH 116/174] ASoC: Add support for BCM2708
+
+This driver adds support for digital audio (I2S)
+for the BCM2708 SoC that is used by the
+Raspberry Pi. External audio codecs can be
+connected to the Raspberry Pi via P5 header.
+
+It relies on cyclic DMA engine support for BCM2708.
+
+Signed-off-by: Florian Meier <florian.meier@koalo.de>
+---
+ sound/soc/Kconfig | 1 +
+ sound/soc/Makefile | 1 +
+ sound/soc/bcm/Kconfig | 10 +
+ sound/soc/bcm/Makefile | 4 +
+ sound/soc/bcm/bcm2708-i2s.c | 940 ++++++++++++++++++++++++++++++++++++++++++++
+ 5 files changed, 956 insertions(+)
+ create mode 100644 sound/soc/bcm/Kconfig
+ create mode 100644 sound/soc/bcm/Makefile
+ create mode 100644 sound/soc/bcm/bcm2708-i2s.c
+
+--- a/sound/soc/Kconfig
++++ b/sound/soc/Kconfig
+@@ -36,6 +36,7 @@ config SND_SOC_GENERIC_DMAENGINE_PCM
+ # All the supported SoCs
+ source "sound/soc/atmel/Kconfig"
+ source "sound/soc/au1x/Kconfig"
++source "sound/soc/bcm/Kconfig"
+ source "sound/soc/blackfin/Kconfig"
+ source "sound/soc/cirrus/Kconfig"
+ source "sound/soc/davinci/Kconfig"
+--- a/sound/soc/Makefile
++++ b/sound/soc/Makefile
+@@ -14,6 +14,7 @@ obj-$(CONFIG_SND_SOC) += codecs/
+ obj-$(CONFIG_SND_SOC) += generic/
+ obj-$(CONFIG_SND_SOC) += atmel/
+ obj-$(CONFIG_SND_SOC) += au1x/
++obj-$(CONFIG_SND_SOC) += bcm/
+ obj-$(CONFIG_SND_SOC) += blackfin/
+ obj-$(CONFIG_SND_SOC) += cirrus/
+ obj-$(CONFIG_SND_SOC) += davinci/
+--- /dev/null
++++ b/sound/soc/bcm/Kconfig
+@@ -0,0 +1,10 @@
++config SND_BCM2708_SOC_I2S
++ tristate "SoC Audio support for the Broadcom BCM2708 I2S module"
++ depends on MACH_BCM2708
++ select REGMAP_MMIO
++ select SND_SOC_DMAENGINE_PCM
++ select SND_SOC_GENERIC_DMAENGINE_PCM
++ help
++ Say Y or M if you want to add support for codecs attached to
++ the BCM2708 I2S interface. You will also need
++ to select the audio interfaces to support below.
+--- /dev/null
++++ b/sound/soc/bcm/Makefile
+@@ -0,0 +1,4 @@
++# BCM2708 Platform Support
++snd-soc-bcm2708-i2s-objs := bcm2708-i2s.o
++
++obj-$(CONFIG_SND_BCM2708_SOC_I2S) += snd-soc-bcm2708-i2s.o
+--- /dev/null
++++ b/sound/soc/bcm/bcm2708-i2s.c
+@@ -0,0 +1,940 @@
++/*
++ * ALSA SoC I2S Audio Layer for Broadcom BCM2708 SoC
++ *
++ * Author: Florian Meier <florian.meier@koalo.de>
++ * Copyright 2013
++ *
++ * Based on
++ * Raspberry Pi PCM I2S ALSA Driver
++ * Copyright (c) by Phil Poole 2013
++ *
++ * ALSA SoC I2S (McBSP) Audio Layer for TI DAVINCI processor
++ * Vladimir Barinov, <vbarinov@embeddedalley.com>
++ * Copyright (C) 2007 MontaVista Software, Inc., <source@mvista.com>
++ *
++ * OMAP ALSA SoC DAI driver using McBSP port
++ * Copyright (C) 2008 Nokia Corporation
++ * Contact: Jarkko Nikula <jarkko.nikula@bitmer.com>
++ * Peter Ujfalusi <peter.ujfalusi@ti.com>
++ *
++ * Freescale SSI ALSA SoC Digital Audio Interface (DAI) driver
++ * Author: Timur Tabi <timur@freescale.com>
++ * Copyright 2007-2010 Freescale Semiconductor, Inc.
++ *
++ * This program is free software; you can redistribute it and/or
++ * modify it under the terms of the GNU General Public License
++ * version 2 as published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful, but
++ * WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
++ * General Public License for more details.
++ */
++
++#include <linux/init.h>
++#include <linux/module.h>
++#include <linux/device.h>
++#include <linux/slab.h>
++#include <linux/delay.h>
++#include <linux/io.h>
++#include <linux/clk.h>
++
++#include <sound/core.h>
++#include <sound/pcm.h>
++#include <sound/pcm_params.h>
++#include <sound/initval.h>
++#include <sound/soc.h>
++#include <sound/dmaengine_pcm.h>
++
++/* Clock registers */
++#define BCM2708_CLK_PCMCTL_REG 0x00
++#define BCM2708_CLK_PCMDIV_REG 0x04
++
++/* Clock register settings */
++#define BCM2708_CLK_PASSWD (0x5a000000)
++#define BCM2708_CLK_PASSWD_MASK (0xff000000)
++#define BCM2708_CLK_MASH(v) ((v) << 9)
++#define BCM2708_CLK_FLIP BIT(8)
++#define BCM2708_CLK_BUSY BIT(7)
++#define BCM2708_CLK_KILL BIT(5)
++#define BCM2708_CLK_ENAB BIT(4)
++#define BCM2708_CLK_SRC(v) (v)
++
++#define BCM2708_CLK_SHIFT (12)
++#define BCM2708_CLK_DIVI(v) ((v) << BCM2708_CLK_SHIFT)
++#define BCM2708_CLK_DIVF(v) (v)
++#define BCM2708_CLK_DIVF_MASK (0xFFF)
++
++enum {
++ BCM2708_CLK_MASH_0 = 0,
++ BCM2708_CLK_MASH_1,
++ BCM2708_CLK_MASH_2,
++ BCM2708_CLK_MASH_3,
++};
++
++enum {
++ BCM2708_CLK_SRC_GND = 0,
++ BCM2708_CLK_SRC_OSC,
++ BCM2708_CLK_SRC_DBG0,
++ BCM2708_CLK_SRC_DBG1,
++ BCM2708_CLK_SRC_PLLA,
++ BCM2708_CLK_SRC_PLLC,
++ BCM2708_CLK_SRC_PLLD,
++ BCM2708_CLK_SRC_HDMI,
++};
++
++/* Most clocks are not useable (freq = 0) */
++static const unsigned int bcm2708_clk_freq[BCM2708_CLK_SRC_HDMI+1] = {
++ [BCM2708_CLK_SRC_GND] = 0,
++ [BCM2708_CLK_SRC_OSC] = 19200000,
++ [BCM2708_CLK_SRC_DBG0] = 0,
++ [BCM2708_CLK_SRC_DBG1] = 0,
++ [BCM2708_CLK_SRC_PLLA] = 0,
++ [BCM2708_CLK_SRC_PLLC] = 0,
++ [BCM2708_CLK_SRC_PLLD] = 500000000,
++ [BCM2708_CLK_SRC_HDMI] = 0,
++};
++
++/* I2S registers */
++#define BCM2708_I2S_CS_A_REG 0x00
++#define BCM2708_I2S_FIFO_A_REG 0x04
++#define BCM2708_I2S_MODE_A_REG 0x08
++#define BCM2708_I2S_RXC_A_REG 0x0c
++#define BCM2708_I2S_TXC_A_REG 0x10
++#define BCM2708_I2S_DREQ_A_REG 0x14
++#define BCM2708_I2S_INTEN_A_REG 0x18
++#define BCM2708_I2S_INTSTC_A_REG 0x1c
++#define BCM2708_I2S_GRAY_REG 0x20
++
++/* I2S register settings */
++#define BCM2708_I2S_STBY BIT(25)
++#define BCM2708_I2S_SYNC BIT(24)
++#define BCM2708_I2S_RXSEX BIT(23)
++#define BCM2708_I2S_RXF BIT(22)
++#define BCM2708_I2S_TXE BIT(21)
++#define BCM2708_I2S_RXD BIT(20)
++#define BCM2708_I2S_TXD BIT(19)
++#define BCM2708_I2S_RXR BIT(18)
++#define BCM2708_I2S_TXW BIT(17)
++#define BCM2708_I2S_CS_RXERR BIT(16)
++#define BCM2708_I2S_CS_TXERR BIT(15)
++#define BCM2708_I2S_RXSYNC BIT(14)
++#define BCM2708_I2S_TXSYNC BIT(13)
++#define BCM2708_I2S_DMAEN BIT(9)
++#define BCM2708_I2S_RXTHR(v) ((v) << 7)
++#define BCM2708_I2S_TXTHR(v) ((v) << 5)
++#define BCM2708_I2S_RXCLR BIT(4)
++#define BCM2708_I2S_TXCLR BIT(3)
++#define BCM2708_I2S_TXON BIT(2)
++#define BCM2708_I2S_RXON BIT(1)
++#define BCM2708_I2S_EN (1)
++
++#define BCM2708_I2S_CLKDIS BIT(28)
++#define BCM2708_I2S_PDMN BIT(27)
++#define BCM2708_I2S_PDME BIT(26)
++#define BCM2708_I2S_FRXP BIT(25)
++#define BCM2708_I2S_FTXP BIT(24)
++#define BCM2708_I2S_CLKM BIT(23)
++#define BCM2708_I2S_CLKI BIT(22)
++#define BCM2708_I2S_FSM BIT(21)
++#define BCM2708_I2S_FSI BIT(20)
++#define BCM2708_I2S_FLEN(v) ((v) << 10)
++#define BCM2708_I2S_FSLEN(v) (v)
++
++#define BCM2708_I2S_CHWEX BIT(15)
++#define BCM2708_I2S_CHEN BIT(14)
++#define BCM2708_I2S_CHPOS(v) ((v) << 4)
++#define BCM2708_I2S_CHWID(v) (v)
++#define BCM2708_I2S_CH1(v) ((v) << 16)
++#define BCM2708_I2S_CH2(v) (v)
++
++#define BCM2708_I2S_TX_PANIC(v) ((v) << 24)
++#define BCM2708_I2S_RX_PANIC(v) ((v) << 16)
++#define BCM2708_I2S_TX(v) ((v) << 8)
++#define BCM2708_I2S_RX(v) (v)
++
++#define BCM2708_I2S_INT_RXERR BIT(3)
++#define BCM2708_I2S_INT_TXERR BIT(2)
++#define BCM2708_I2S_INT_RXR BIT(1)
++#define BCM2708_I2S_INT_TXW BIT(0)
++
++/* I2S DMA interface */
++#define BCM2708_I2S_FIFO_PHYSICAL_ADDR 0x7E203004
++#define BCM2708_DMA_DREQ_PCM_TX 2
++#define BCM2708_DMA_DREQ_PCM_RX 3
++
++/* General device struct */
++struct bcm2708_i2s_dev {
++ struct device *dev;
++ struct snd_dmaengine_dai_dma_data dma_data[2];
++ unsigned int fmt;
++ unsigned int bclk_ratio;
++
++ struct regmap *i2s_regmap;
++ struct regmap *clk_regmap;
++};
++
++static void bcm2708_i2s_start_clock(struct bcm2708_i2s_dev *dev)
++{
++ /* Start the clock if in master mode */
++ unsigned int master = dev->fmt & SND_SOC_DAIFMT_MASTER_MASK;
++
++ switch (master) {
++ case SND_SOC_DAIFMT_CBS_CFS:
++ case SND_SOC_DAIFMT_CBS_CFM:
++ regmap_update_bits(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG,
++ BCM2708_CLK_PASSWD_MASK | BCM2708_CLK_ENAB,
++ BCM2708_CLK_PASSWD | BCM2708_CLK_ENAB);
++ break;
++ default:
++ break;
++ }
++}
++
++static void bcm2708_i2s_stop_clock(struct bcm2708_i2s_dev *dev)
++{
++ uint32_t clkreg;
++ int timeout = 1000;
++
++ /* Stop clock */
++ regmap_update_bits(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG,
++ BCM2708_CLK_PASSWD_MASK | BCM2708_CLK_ENAB,
++ BCM2708_CLK_PASSWD);
++
++ /* Wait for the BUSY flag going down */
++ while (--timeout) {
++ regmap_read(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG, &clkreg);
++ if (!(clkreg & BCM2708_CLK_BUSY))
++ break;
++ }
++
++ if (!timeout) {
++ /* KILL the clock */
++ dev_err(dev->dev, "I2S clock didn't stop. Kill the clock!\n");
++ regmap_update_bits(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG,
++ BCM2708_CLK_KILL | BCM2708_CLK_PASSWD_MASK,
++ BCM2708_CLK_KILL | BCM2708_CLK_PASSWD);
++ }
++}
++
++static void bcm2708_i2s_clear_fifos(struct bcm2708_i2s_dev *dev,
++ bool tx, bool rx)
++{
++ int timeout = 1000;
++ uint32_t syncval;
++ uint32_t csreg;
++ uint32_t i2s_active_state;
++ uint32_t clkreg;
++ uint32_t clk_active_state;
++ uint32_t off;
++ uint32_t clr;
++
++ off = tx ? BCM2708_I2S_TXON : 0;
++ off |= rx ? BCM2708_I2S_RXON : 0;
++
++ clr = tx ? BCM2708_I2S_TXCLR : 0;
++ clr |= rx ? BCM2708_I2S_RXCLR : 0;
++
++ /* Backup the current state */
++ regmap_read(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, &csreg);
++ i2s_active_state = csreg & (BCM2708_I2S_RXON | BCM2708_I2S_TXON);
++
++ regmap_read(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG, &clkreg);
++ clk_active_state = clkreg & BCM2708_CLK_ENAB;
++
++ /* Start clock if not running */
++ if (!clk_active_state) {
++ regmap_update_bits(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG,
++ BCM2708_CLK_PASSWD_MASK | BCM2708_CLK_ENAB,
++ BCM2708_CLK_PASSWD | BCM2708_CLK_ENAB);
++ }
++
++ /* Stop I2S module */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, off, 0);
++
++ /*
++ * Clear the FIFOs
++ * Requires at least 2 PCM clock cycles to take effect
++ */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, clr, clr);
++
++ /* Wait for 2 PCM clock cycles */
++
++ /*
++ * Toggle the SYNC flag. After 2 PCM clock cycles it can be read back
++ * FIXME: This does not seem to work for slave mode!
++ */
++ regmap_read(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, &syncval);
++ syncval &= BCM2708_I2S_SYNC;
++
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG,
++ BCM2708_I2S_SYNC, ~syncval);
++
++ /* Wait for the SYNC flag changing it's state */
++ while (--timeout) {
++ regmap_read(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, &csreg);
++ if ((csreg & BCM2708_I2S_SYNC) != syncval)
++ break;
++ }
++
++ if (!timeout)
++ dev_err(dev->dev, "I2S SYNC error!\n");
++
++ /* Stop clock if it was not running before */
++ if (!clk_active_state)
++ bcm2708_i2s_stop_clock(dev);
++
++ /* Restore I2S state */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG,
++ BCM2708_I2S_RXON | BCM2708_I2S_TXON, i2s_active_state);
++}
++
++static int bcm2708_i2s_set_dai_fmt(struct snd_soc_dai *dai,
++ unsigned int fmt)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++ dev->fmt = fmt;
++ return 0;
++}
++
++static int bcm2708_i2s_set_dai_bclk_ratio(struct snd_soc_dai *dai,
++ unsigned int ratio)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++ dev->bclk_ratio = ratio;
++ return 0;
++}
++
++static int bcm2708_i2s_hw_params(struct snd_pcm_substream *substream,
++ struct snd_pcm_hw_params *params,
++ struct snd_soc_dai *dai)
++{
++ struct bcm2708_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 mash = BCM2708_CLK_MASH_1;
++ unsigned int divi, divf, target_frequency;
++ int clk_src = -1;
++ unsigned int master = dev->fmt & SND_SOC_DAIFMT_MASTER_MASK;
++ bool bit_master = (master == SND_SOC_DAIFMT_CBS_CFS
++ || master == SND_SOC_DAIFMT_CBS_CFM);
++
++ bool frame_master = (master == SND_SOC_DAIFMT_CBS_CFS
++ || master == SND_SOC_DAIFMT_CBM_CFS);
++ uint32_t csreg;
++
++ /*
++ * If a stream is already enabled,
++ * the registers are already set properly.
++ */
++ regmap_read(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, &csreg);
++
++ if (csreg & (BCM2708_I2S_TXON | BCM2708_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;
++ bclk_ratio = 40;
++ break;
++ case SNDRV_PCM_FORMAT_S32_LE:
++ data_length = 32;
++ bclk_ratio = 80;
++ break;
++ default:
++ return -EINVAL;
++ }
++
++ /* If bclk_ratio already set, use that one. */
++ if (dev->bclk_ratio)
++ bclk_ratio = dev->bclk_ratio;
++
++ /*
++ * Clock Settings
++ *
++ * The target frequency of the bit clock is
++ * sampling rate * frame length
++ *
++ * Integer mode:
++ * Sampling rates that are multiples of 8000 kHz
++ * can be driven by the oscillator of 19.2 MHz
++ * with an integer divider as long as the frame length
++ * is an integer divider of 19200000/8000=2400 as set up above.
++ * This is no longer possible if the sampling rate
++ * is too high (e.g. 192 kHz), because the oscillator is too slow.
++ *
++ * MASH mode:
++ * For all other sampling rates, it is not possible to
++ * have an integer divider. Approximate the clock
++ * with the MASH module that induces a slight frequency
++ * variance. To minimize that it is best to have the fastest
++ * clock here. That is PLLD with 500 MHz.
++ */
++ target_frequency = sampling_rate * bclk_ratio;
++ clk_src = BCM2708_CLK_SRC_OSC;
++ mash = BCM2708_CLK_MASH_0;
++
++ if (bcm2708_clk_freq[clk_src] % target_frequency == 0
++ && bit_master && frame_master) {
++ divi = bcm2708_clk_freq[clk_src] / target_frequency;
++ divf = 0;
++ } else {
++ uint64_t dividend;
++
++ if (!dev->bclk_ratio) {
++ /*
++ * Overwrite bclk_ratio, because the
++ * above trick is not needed or can
++ * not be used.
++ */
++ bclk_ratio = 2 * data_length;
++ }
++
++ target_frequency = sampling_rate * bclk_ratio;
++
++ clk_src = BCM2708_CLK_SRC_PLLD;
++ mash = BCM2708_CLK_MASH_1;
++
++ dividend = bcm2708_clk_freq[clk_src];
++ dividend <<= BCM2708_CLK_SHIFT;
++ do_div(dividend, target_frequency);
++ divi = dividend >> BCM2708_CLK_SHIFT;
++ divf = dividend & BCM2708_CLK_DIVF_MASK;
++ }
++
++ /* Set clock divider */
++ regmap_write(dev->clk_regmap, BCM2708_CLK_PCMDIV_REG, BCM2708_CLK_PASSWD
++ | BCM2708_CLK_DIVI(divi)
++ | BCM2708_CLK_DIVF(divf));
++
++ /* Setup clock, but don't start it yet */
++ regmap_write(dev->clk_regmap, BCM2708_CLK_PCMCTL_REG, BCM2708_CLK_PASSWD
++ | BCM2708_CLK_MASH(mash)
++ | BCM2708_CLK_SRC(clk_src));
++
++ /* Setup the frame format */
++ format = BCM2708_I2S_CHEN;
++
++ if (data_length > 24)
++ format |= BCM2708_I2S_CHWEX;
++
++ format |= BCM2708_I2S_CHWID((data_length-8)&0xf);
++
++ switch (dev->fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
++ case SND_SOC_DAIFMT_I2S:
++ data_delay = 1;
++ break;
++ default:
++ /*
++ * TODO
++ * Others are possible but are not implemented at the moment.
++ */
++ dev_err(dev->dev, "%s:bad format\n", __func__);
++ return -EINVAL;
++ }
++
++ ch1pos = data_delay;
++ ch2pos = bclk_ratio / 2 + data_delay;
++
++ switch (params_channels(params)) {
++ case 2:
++ format = BCM2708_I2S_CH1(format) | BCM2708_I2S_CH2(format);
++ format |= BCM2708_I2S_CH1(BCM2708_I2S_CHPOS(ch1pos));
++ format |= BCM2708_I2S_CH2(BCM2708_I2S_CHPOS(ch2pos));
++ break;
++ default:
++ return -EINVAL;
++ }
++
++ /*
++ * Set format for both streams.
++ * We cannot set another frame length
++ * (and therefore word length) anyway,
++ * so the format will be the same.
++ */
++ regmap_write(dev->i2s_regmap, BCM2708_I2S_RXC_A_REG, format);
++ regmap_write(dev->i2s_regmap, BCM2708_I2S_TXC_A_REG, format);
++
++ /* Setup the I2S mode */
++ mode = 0;
++
++ if (data_length <= 16) {
++ /*
++ * Use frame packed mode (2 channels per 32 bit word)
++ * We cannot set another frame length in the second stream
++ * (and therefore word length) anyway,
++ * so the format will be the same.
++ */
++ mode |= BCM2708_I2S_FTXP | BCM2708_I2S_FRXP;
++ }
++
++ mode |= BCM2708_I2S_FLEN(bclk_ratio - 1);
++ mode |= BCM2708_I2S_FSLEN(bclk_ratio / 2);
++
++ /* Master or slave? */
++ switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
++ case SND_SOC_DAIFMT_CBS_CFS:
++ /* CPU is master */
++ break;
++ case SND_SOC_DAIFMT_CBM_CFS:
++ /*
++ * CODEC is bit clock master
++ * CPU is frame master
++ */
++ mode |= BCM2708_I2S_CLKM;
++ break;
++ case SND_SOC_DAIFMT_CBS_CFM:
++ /*
++ * CODEC is frame master
++ * CPU is bit clock master
++ */
++ mode |= BCM2708_I2S_FSM;
++ break;
++ case SND_SOC_DAIFMT_CBM_CFM:
++ /* CODEC is master */
++ mode |= BCM2708_I2S_CLKM;
++ mode |= BCM2708_I2S_FSM;
++ break;
++ default:
++ dev_err(dev->dev, "%s:bad master\n", __func__);
++ return -EINVAL;
++ }
++
++ /*
++ * Invert clocks?
++ *
++ * The BCM approach seems to be inverted to the classical I2S approach.
++ */
++ switch (dev->fmt & SND_SOC_DAIFMT_INV_MASK) {
++ case SND_SOC_DAIFMT_NB_NF:
++ /* None. Therefore, both for BCM */
++ mode |= BCM2708_I2S_CLKI;
++ mode |= BCM2708_I2S_FSI;
++ break;
++ case SND_SOC_DAIFMT_IB_IF:
++ /* Both. Therefore, none for BCM */
++ break;
++ case SND_SOC_DAIFMT_NB_IF:
++ /*
++ * Invert only frame sync. Therefore,
++ * invert only bit clock for BCM
++ */
++ mode |= BCM2708_I2S_CLKI;
++ break;
++ case SND_SOC_DAIFMT_IB_NF:
++ /*
++ * Invert only bit clock. Therefore,
++ * invert only frame sync for BCM
++ */
++ mode |= BCM2708_I2S_FSI;
++ break;
++ default:
++ return -EINVAL;
++ }
++
++ regmap_write(dev->i2s_regmap, BCM2708_I2S_MODE_A_REG, mode);
++
++ /* Setup the DMA parameters */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG,
++ BCM2708_I2S_RXTHR(1)
++ | BCM2708_I2S_TXTHR(1)
++ | BCM2708_I2S_DMAEN, 0xffffffff);
++
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_DREQ_A_REG,
++ BCM2708_I2S_TX_PANIC(0x10)
++ | BCM2708_I2S_RX_PANIC(0x30)
++ | BCM2708_I2S_TX(0x30)
++ | BCM2708_I2S_RX(0x20), 0xffffffff);
++
++ /* Clear FIFOs */
++ bcm2708_i2s_clear_fifos(dev, true, true);
++
++ return 0;
++}
++
++static int bcm2708_i2s_prepare(struct snd_pcm_substream *substream,
++ struct snd_soc_dai *dai)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++ uint32_t cs_reg;
++
++ bcm2708_i2s_start_clock(dev);
++
++ /*
++ * Clear both FIFOs if the one that should be started
++ * is not empty at the moment. This should only happen
++ * after overrun. Otherwise, hw_params would have cleared
++ * the FIFO.
++ */
++ regmap_read(dev->i2s_regmap, BCM2708_I2S_CS_A_REG, &cs_reg);
++
++ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
++ && !(cs_reg & BCM2708_I2S_TXE))
++ bcm2708_i2s_clear_fifos(dev, true, false);
++ else if (substream->stream == SNDRV_PCM_STREAM_CAPTURE
++ && (cs_reg & BCM2708_I2S_RXD))
++ bcm2708_i2s_clear_fifos(dev, false, true);
++
++ return 0;
++}
++
++static void bcm2708_i2s_stop(struct bcm2708_i2s_dev *dev,
++ struct snd_pcm_substream *substream,
++ struct snd_soc_dai *dai)
++{
++ uint32_t mask;
++
++ if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
++ mask = BCM2708_I2S_RXON;
++ else
++ mask = BCM2708_I2S_TXON;
++
++ regmap_update_bits(dev->i2s_regmap,
++ BCM2708_I2S_CS_A_REG, mask, 0);
++
++ /* Stop also the clock when not SND_SOC_DAIFMT_CONT */
++ if (!dai->active && !(dev->fmt & SND_SOC_DAIFMT_CONT))
++ bcm2708_i2s_stop_clock(dev);
++}
++
++static int bcm2708_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
++ struct snd_soc_dai *dai)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++ uint32_t mask;
++
++ switch (cmd) {
++ case SNDRV_PCM_TRIGGER_START:
++ case SNDRV_PCM_TRIGGER_RESUME:
++ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
++ bcm2708_i2s_start_clock(dev);
++
++ if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
++ mask = BCM2708_I2S_RXON;
++ else
++ mask = BCM2708_I2S_TXON;
++
++ regmap_update_bits(dev->i2s_regmap,
++ BCM2708_I2S_CS_A_REG, mask, mask);
++ break;
++
++ case SNDRV_PCM_TRIGGER_STOP:
++ case SNDRV_PCM_TRIGGER_SUSPEND:
++ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
++ bcm2708_i2s_stop(dev, substream, dai);
++ break;
++ default:
++ return -EINVAL;
++ }
++
++ return 0;
++}
++
++static int bcm2708_i2s_startup(struct snd_pcm_substream *substream,
++ struct snd_soc_dai *dai)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++
++ if (dai->active)
++ return 0;
++
++ /* Should this still be running stop it */
++ bcm2708_i2s_stop_clock(dev);
++
++ /* Enable PCM block */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG,
++ BCM2708_I2S_EN, BCM2708_I2S_EN);
++
++ /*
++ * Disable STBY.
++ * Requires at least 4 PCM clock cycles to take effect.
++ */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG,
++ BCM2708_I2S_STBY, BCM2708_I2S_STBY);
++
++ return 0;
++}
++
++static void bcm2708_i2s_shutdown(struct snd_pcm_substream *substream,
++ struct snd_soc_dai *dai)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++
++ bcm2708_i2s_stop(dev, substream, dai);
++
++ /* If both streams are stopped, disable module and clock */
++ if (dai->active)
++ return;
++
++ /* Disable the module */
++ regmap_update_bits(dev->i2s_regmap, BCM2708_I2S_CS_A_REG,
++ BCM2708_I2S_EN, 0);
++
++ /*
++ * Stopping clock is necessary, because stop does
++ * not stop the clock when SND_SOC_DAIFMT_CONT
++ */
++ bcm2708_i2s_stop_clock(dev);
++}
++
++static const struct snd_soc_dai_ops bcm2708_i2s_dai_ops = {
++ .startup = bcm2708_i2s_startup,
++ .shutdown = bcm2708_i2s_shutdown,
++ .prepare = bcm2708_i2s_prepare,
++ .trigger = bcm2708_i2s_trigger,
++ .hw_params = bcm2708_i2s_hw_params,
++ .set_fmt = bcm2708_i2s_set_dai_fmt,
++ .set_bclk_ratio = bcm2708_i2s_set_dai_bclk_ratio
++};
++
++static int bcm2708_i2s_dai_probe(struct snd_soc_dai *dai)
++{
++ struct bcm2708_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
++
++ dai->playback_dma_data = &dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK];
++ dai->capture_dma_data = &dev->dma_data[SNDRV_PCM_STREAM_CAPTURE];
++
++ return 0;
++}
++
++static struct snd_soc_dai_driver bcm2708_i2s_dai = {
++ .name = "bcm2708-i2s",
++ .probe = bcm2708_i2s_dai_probe,
++ .playback = {
++ .channels_min = 2,
++ .channels_max = 2,
++ .rates = SNDRV_PCM_RATE_8000_192000,
++ .formats = SNDRV_PCM_FMTBIT_S16_LE
++ | SNDRV_PCM_FMTBIT_S32_LE
++ },
++ .capture = {
++ .channels_min = 2,
++ .channels_max = 2,
++ .rates = SNDRV_PCM_RATE_8000_192000,
++ .formats = SNDRV_PCM_FMTBIT_S16_LE
++ | SNDRV_PCM_FMTBIT_S32_LE
++ },
++ .ops = &bcm2708_i2s_dai_ops,
++ .symmetric_rates = 1
++};
++
++static bool bcm2708_i2s_volatile_reg(struct device *dev, unsigned int reg)
++{
++ switch (reg) {
++ case BCM2708_I2S_CS_A_REG:
++ case BCM2708_I2S_FIFO_A_REG:
++ case BCM2708_I2S_INTSTC_A_REG:
++ case BCM2708_I2S_GRAY_REG:
++ return true;
++ default:
++ return false;
++ };
++}
++
++static bool bcm2708_i2s_precious_reg(struct device *dev, unsigned int reg)
++{
++ switch (reg) {
++ case BCM2708_I2S_FIFO_A_REG:
++ return true;
++ default:
++ return false;
++ };
++}
++
++static bool bcm2708_clk_volatile_reg(struct device *dev, unsigned int reg)
++{
++ switch (reg) {
++ case BCM2708_CLK_PCMCTL_REG:
++ return true;
++ default:
++ return false;
++ };
++}
++
++static const struct regmap_config bcm2708_regmap_config[] = {
++ {
++ .reg_bits = 32,
++ .reg_stride = 4,
++ .val_bits = 32,
++ .max_register = BCM2708_I2S_GRAY_REG,
++ .precious_reg = bcm2708_i2s_precious_reg,
++ .volatile_reg = bcm2708_i2s_volatile_reg,
++ .cache_type = REGCACHE_RBTREE,
++ },
++ {
++ .reg_bits = 32,
++ .reg_stride = 4,
++ .val_bits = 32,
++ .max_register = BCM2708_CLK_PCMDIV_REG,
++ .volatile_reg = bcm2708_clk_volatile_reg,
++ .cache_type = REGCACHE_RBTREE,
++ },
++};
++
++static const struct snd_soc_component_driver bcm2708_i2s_component = {
++ .name = "bcm2708-i2s-comp",
++};
++
++
++static void bcm2708_i2s_setup_gpio(void)
++{
++ /*
++ * This is the common way to handle the GPIO pins for
++ * the Raspberry Pi.
++ * TODO Better way would be to handle
++ * this in the device tree!
++ */
++#define INP_GPIO(g) *(gpio+((g)/10)) &= ~(7<<(((g)%10)*3))
++#define SET_GPIO_ALT(g,a) *(gpio+(((g)/10))) |= (((a)<=3?(a)+4:(a)==4?3:2)<<(((g)%10)*3))
++
++ unsigned int *gpio;
++ int pin;
++ gpio = ioremap(GPIO_BASE, SZ_16K);
++
++ /* SPI is on GPIO 7..11 */
++ for (pin = 28; pin <= 31; pin++) {
++ INP_GPIO(pin); /* set mode to GPIO input first */
++ SET_GPIO_ALT(pin, 2); /* set mode to ALT 0 */
++ }
++#undef INP_GPIO
++#undef SET_GPIO_ALT
++}
++
++static const struct snd_pcm_hardware bcm2708_pcm_hardware = {
++ .info = SNDRV_PCM_INFO_MMAP |
++ SNDRV_PCM_INFO_MMAP_VALID |
++ SNDRV_PCM_INFO_INTERLEAVED |
++ SNDRV_PCM_INFO_JOINT_DUPLEX,
++ .formats = SNDRV_PCM_FMTBIT_S16_LE |
++ SNDRV_PCM_FMTBIT_S32_LE,
++ .period_bytes_min = 32,
++ .period_bytes_max = 64 * PAGE_SIZE,
++ .periods_min = 2,
++ .periods_max = 255,
++ .buffer_bytes_max = 128 * PAGE_SIZE,
++};
++
++static const struct snd_dmaengine_pcm_config bcm2708_dmaengine_pcm_config = {
++ .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
++ .pcm_hardware = &bcm2708_pcm_hardware,
++ .prealloc_buffer_size = 256 * PAGE_SIZE,
++};
++
++
++static int bcm2708_i2s_probe(struct platform_device *pdev)
++{
++ struct bcm2708_i2s_dev *dev;
++ int i;
++ int ret;
++ struct regmap *regmap[2];
++ struct resource *mem[2];
++
++ /* Request both ioareas */
++ for (i = 0; i <= 1; i++) {
++ void __iomem *base;
++
++ mem[i] = platform_get_resource(pdev, IORESOURCE_MEM, i);
++ base = devm_ioremap_resource(&pdev->dev, mem[i]);
++ if (IS_ERR(base))
++ return PTR_ERR(base);
++
++ regmap[i] = devm_regmap_init_mmio(&pdev->dev, base,
++ &bcm2708_regmap_config[i]);
++ if (IS_ERR(regmap[i])) {
++ dev_err(&pdev->dev, "I2S probe: regmap init failed\n");
++ return PTR_ERR(regmap[i]);
++ }
++ }
++
++ dev = devm_kzalloc(&pdev->dev, sizeof(*dev),
++ GFP_KERNEL);
++ if (IS_ERR(dev))
++ return PTR_ERR(dev);
++
++ bcm2708_i2s_setup_gpio();
++
++ dev->i2s_regmap = regmap[0];
++ dev->clk_regmap = regmap[1];
++
++ /* Set the DMA address */
++ dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr =
++ (dma_addr_t)BCM2708_I2S_FIFO_PHYSICAL_ADDR;
++
++ dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr =
++ (dma_addr_t)BCM2708_I2S_FIFO_PHYSICAL_ADDR;
++
++ /* Set the DREQ */
++ dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].slave_id =
++ BCM2708_DMA_DREQ_PCM_TX;
++ dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].slave_id =
++ BCM2708_DMA_DREQ_PCM_RX;
++
++ /* Set the bus width */
++ dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr_width =
++ DMA_SLAVE_BUSWIDTH_4_BYTES;
++ dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr_width =
++ DMA_SLAVE_BUSWIDTH_4_BYTES;
++
++ /* Set burst */
++ dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].maxburst = 2;
++ dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].maxburst = 2;
++
++ /* BCLK ratio - use default */
++ dev->bclk_ratio = 0;
++
++ /* Store the pdev */
++ dev->dev = &pdev->dev;
++ dev_set_drvdata(&pdev->dev, dev);
++
++ ret = snd_soc_register_component(&pdev->dev,
++ &bcm2708_i2s_component, &bcm2708_i2s_dai, 1);
++
++ if (ret) {
++ dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
++ ret = -ENOMEM;
++ return ret;
++ }
++
++ ret = snd_dmaengine_pcm_register(&pdev->dev,
++ &bcm2708_dmaengine_pcm_config,
++ SND_DMAENGINE_PCM_FLAG_COMPAT);
++ if (ret) {
++ dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
++ snd_soc_unregister_component(&pdev->dev);
++ return ret;
++ }
++
++ return 0;
++}
++
++static int bcm2708_i2s_remove(struct platform_device *pdev)
++{
++ snd_dmaengine_pcm_unregister(&pdev->dev);
++ snd_soc_unregister_component(&pdev->dev);
++ return 0;
++}
++
++static struct platform_driver bcm2708_i2s_driver = {
++ .probe = bcm2708_i2s_probe,
++ .remove = bcm2708_i2s_remove,
++ .driver = {
++ .name = "bcm2708-i2s",
++ .owner = THIS_MODULE,
++ },
++};
++
++module_platform_driver(bcm2708_i2s_driver);
++
++MODULE_ALIAS("platform:bcm2708-i2s");
++MODULE_DESCRIPTION("BCM2708 I2S interface");
++MODULE_AUTHOR("Florian Meier <florian.meier@koalo.de>");
++MODULE_LICENSE("GPL v2");
generated by cgit v1.1 at 2024-11-10 07:58:04 +0000