diff options
| -rw-r--r-- | Documentation/devicetree/bindings/sound/bcm2835-i2s.txt | 25 | ||||
| -rw-r--r-- | sound/soc/Kconfig | 1 | ||||
| -rw-r--r-- | sound/soc/Makefile | 1 | ||||
| -rw-r--r-- | sound/soc/bcm/Kconfig | 10 | ||||
| -rw-r--r-- | sound/soc/bcm/Makefile | 5 | ||||
| -rw-r--r-- | sound/soc/bcm/bcm2835-i2s.c | 886 |
6 files changed, 928 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/sound/bcm2835-i2s.txt b/Documentation/devicetree/bindings/sound/bcm2835-i2s.txt new file mode 100644 index 000000000000..65783de0aedf --- /dev/null +++ b/Documentation/devicetree/bindings/sound/bcm2835-i2s.txt @@ -0,0 +1,25 @@ +* Broadcom BCM2835 SoC I2S/PCM module + +Required properties: +- compatible: "brcm,bcm2835-i2s" +- reg: A list of base address and size entries: + * The first entry should cover the PCM registers + * The second entry should cover the PCM clock registers +- dmas: List of DMA controller phandle and DMA request line ordered pairs. +- dma-names: Identifier string for each DMA request line in the dmas property. + These strings correspond 1:1 with the ordered pairs in dmas. + + One of the DMA channels will be responsible for transmission (should be + named "tx") and one for reception (should be named "rx"). + +Example: + +bcm2835_i2s: i2s@7e203000 { + compatible = "brcm,bcm2835-i2s"; + reg = <0x7e203000 0x20>, + <0x7e101098 0x02>; + + dmas = <&dma 2>, + <&dma 3>; + dma-names = "tx", "rx"; +}; diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig index 5138b8493051..a5e3a70c0d3d 100644 --- a/sound/soc/Kconfig +++ b/sound/soc/Kconfig @@ -33,6 +33,7 @@ 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" diff --git a/sound/soc/Makefile b/sound/soc/Makefile index 8b9e70105dd2..b52d4aad0716 100644 --- a/sound/soc/Makefile +++ b/sound/soc/Makefile @@ -10,6 +10,7 @@ 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/ diff --git a/sound/soc/bcm/Kconfig b/sound/soc/bcm/Kconfig new file mode 100644 index 000000000000..3d82a29ce3a8 --- /dev/null +++ b/sound/soc/bcm/Kconfig @@ -0,0 +1,10 @@ +config SND_BCM2835_SOC_I2S + tristate "SoC Audio support for the Broadcom BCM2835 I2S module" + depends on ARCH_BCM2835 || COMPILE_TEST + select SND_SOC_DMAENGINE_PCM + select SND_SOC_GENERIC_DMAENGINE_PCM + select REGMAP_MMIO + help + Say Y or M if you want to add support for codecs attached to + the BCM2835 I2S interface. You will also need + to select the audio interfaces to support below. diff --git a/sound/soc/bcm/Makefile b/sound/soc/bcm/Makefile new file mode 100644 index 000000000000..bc816b71e5a4 --- /dev/null +++ b/sound/soc/bcm/Makefile @@ -0,0 +1,5 @@ +# BCM2835 Platform Support +snd-soc-bcm2835-i2s-objs := bcm2835-i2s.o + +obj-$(CONFIG_SND_BCM2835_SOC_I2S) += snd-soc-bcm2835-i2s.o + diff --git a/sound/soc/bcm/bcm2835-i2s.c b/sound/soc/bcm/bcm2835-i2s.c new file mode 100644 index 000000000000..f49b007c8b43 --- /dev/null +++ b/sound/soc/bcm/bcm2835-i2s.c @@ -0,0 +1,886 @@ +/* + * ALSA SoC I2S Audio Layer for Broadcom BCM2835 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 BCM2835_CLK_PCMCTL_REG 0x00 +#define BCM2835_CLK_PCMDIV_REG 0x04 + +/* Clock register settings */ +#define BCM2835_CLK_PASSWD (0x5a000000) +#define BCM2835_CLK_PASSWD_MASK (0xff000000) +#define BCM2835_CLK_MASH(v) ((v) << 9) +#define BCM2835_CLK_FLIP BIT(8) +#define BCM2835_CLK_BUSY BIT(7) +#define BCM2835_CLK_KILL BIT(5) +#define BCM2835_CLK_ENAB BIT(4) +#define BCM2835_CLK_SRC(v) (v) + +#define BCM2835_CLK_SHIFT (12) +#define BCM2835_CLK_DIVI(v) ((v) << BCM2835_CLK_SHIFT) +#define BCM2835_CLK_DIVF(v) (v) +#define BCM2835_CLK_DIVF_MASK (0xFFF) + +enum { + BCM2835_CLK_MASH_0 = 0, + BCM2835_CLK_MASH_1, + BCM2835_CLK_MASH_2, + BCM2835_CLK_MASH_3, +}; + +enum { + BCM2835_CLK_SRC_GND = 0, + BCM2835_CLK_SRC_OSC, + BCM2835_CLK_SRC_DBG0, + BCM2835_CLK_SRC_DBG1, + BCM2835_CLK_SRC_PLLA, + BCM2835_CLK_SRC_PLLC, + BCM2835_CLK_SRC_PLLD, + BCM2835_CLK_SRC_HDMI, +}; + +/* Most clocks are not useable (freq = 0) */ +static const unsigned int bcm2835_clk_freq[BCM2835_CLK_SRC_HDMI+1] = { + [BCM2835_CLK_SRC_GND] = 0, + [BCM2835_CLK_SRC_OSC] = 19200000, + [BCM2835_CLK_SRC_DBG0] = 0, + [BCM2835_CLK_SRC_DBG1] = 0, + [BCM2835_CLK_SRC_PLLA] = 0, + [BCM2835_CLK_SRC_PLLC] = 0, + [BCM2835_CLK_SRC_PLLD] = 500000000, + [BCM2835_CLK_SRC_HDMI] = 0, +}; + +/* I2S registers */ +#define BCM2835_I2S_CS_A_REG 0x00 +#define BCM2835_I2S_FIFO_A_REG 0x04 +#define BCM2835_I2S_MODE_A_REG 0x08 +#define BCM2835_I2S_RXC_A_REG 0x0c +#define BCM2835_I2S_TXC_A_REG 0x10 +#define BCM2835_I2S_DREQ_A_REG 0x14 +#define BCM2835_I2S_INTEN_A_REG 0x18 +#define BCM2835_I2S_INTSTC_A_REG 0x1c +#define BCM2835_I2S_GRAY_REG 0x20 + +/* I2S register settings */ +#define BCM2835_I2S_STBY BIT(25) +#define BCM2835_I2S_SYNC BIT(24) +#define BCM2835_I2S_RXSEX BIT(23) +#define BCM2835_I2S_RXF BIT(22) +#define BCM2835_I2S_TXE BIT(21) +#define BCM2835_I2S_RXD BIT(20) +#define BCM2835_I2S_TXD BIT(19) +#define BCM2835_I2S_RXR BIT(18) +#define BCM2835_I2S_TXW BIT(17) +#define BCM2835_I2S_CS_RXERR BIT(16) +#define BCM2835_I2S_CS_TXERR BIT(15) +#define BCM2835_I2S_RXSYNC BIT(14) +#define BCM2835_I2S_TXSYNC BIT(13) +#define BCM2835_I2S_DMAEN BIT(9) +#define BCM2835_I2S_RXTHR(v) ((v) << 7) +#define BCM2835_I2S_TXTHR(v) ((v) << 5) +#define BCM2835_I2S_RXCLR BIT(4) +#define BCM2835_I2S_TXCLR BIT(3) +#define BCM2835_I2S_TXON BIT(2) +#define BCM2835_I2S_RXON BIT(1) +#define BCM2835_I2S_EN (1) + +#define BCM2835_I2S_CLKDIS BIT(28) +#define BCM2835_I2S_PDMN BIT(27) +#define BCM2835_I2S_PDME BIT(26) +#define BCM2835_I2S_FRXP BIT(25) +#define BCM2835_I2S_FTXP BIT(24) +#define BCM2835_I2S_CLKM BIT(23) +#define BCM2835_I2S_CLKI BIT(22) +#define BCM2835_I2S_FSM BIT(21) +#define BCM2835_I2S_FSI BIT(20) +#define BCM2835_I2S_FLEN(v) ((v) << 10) +#define BCM2835_I2S_FSLEN(v) (v) + +#define BCM2835_I2S_CHWEX BIT(15) +#define BCM2835_I2S_CHEN BIT(14) +#define BCM2835_I2S_CHPOS(v) ((v) << 4) +#define BCM2835_I2S_CHWID(v) (v) +#define BCM2835_I2S_CH1(v) ((v) << 16) +#define BCM2835_I2S_CH2(v) (v) + +#define BCM2835_I2S_TX_PANIC(v) ((v) << 24) +#define BCM2835_I2S_RX_PANIC(v) ((v) << 16) +#define BCM2835_I2S_TX(v) ((v) << 8) +#define BCM2835_I2S_RX(v) (v) + +#define BCM2835_I2S_INT_RXERR BIT(3) +#define BCM2835_I2S_INT_TXERR BIT(2) +#define BCM2835_I2S_INT_RXR BIT(1) +#define BCM2835_I2S_INT_TXW BIT(0) + +/* I2S DMA interface */ +/* FIXME: Needs IOMMU support */ +#define BCM2835_VCMMU_SHIFT (0x7E000000 - 0x20000000) + +/* 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; + + struct regmap *i2s_regmap; + struct regmap *clk_regmap; +}; + +static void bcm2835_i2s_start_clock(struct bcm2835_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, BCM2835_CLK_PCMCTL_REG, + BCM2835_CLK_PASSWD_MASK | BCM2835_CLK_ENAB, + BCM2835_CLK_PASSWD | BCM2835_CLK_ENAB); + break; + default: + break; + } +} + +static void bcm2835_i2s_stop_clock(struct bcm2835_i2s_dev *dev) +{ + uint32_t clkreg; + int timeout = 1000; + + /* Stop clock */ + regmap_update_bits(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, + BCM2835_CLK_PASSWD_MASK | BCM2835_CLK_ENAB, + BCM2835_CLK_PASSWD); + + /* Wait for the BUSY flag going down */ + while (--timeout) { + regmap_read(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, &clkreg); + if (!(clkreg & BCM2835_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, BCM2835_CLK_PCMCTL_REG, + BCM2835_CLK_KILL | BCM2835_CLK_PASSWD_MASK, + BCM2835_CLK_KILL | BCM2835_CLK_PASSWD); + } +} + +static void bcm2835_i2s_clear_fifos(struct bcm2835_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 ? BCM2835_I2S_TXON : 0; + off |= rx ? BCM2835_I2S_RXON : 0; + + clr = tx ? BCM2835_I2S_TXCLR : 0; + clr |= rx ? BCM2835_I2S_RXCLR : 0; + + /* Backup the current state */ + regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &csreg); + i2s_active_state = csreg & (BCM2835_I2S_RXON | BCM2835_I2S_TXON); + + regmap_read(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, &clkreg); + clk_active_state = clkreg & BCM2835_CLK_ENAB; + + /* Start clock if not running */ + if (!clk_active_state) { + regmap_update_bits(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, + BCM2835_CLK_PASSWD_MASK | BCM2835_CLK_ENAB, + BCM2835_CLK_PASSWD | BCM2835_CLK_ENAB); + } + + /* Stop I2S module */ + regmap_update_bits(dev->i2s_regmap, BCM2835_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, BCM2835_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, BCM2835_I2S_CS_A_REG, &syncval); + syncval &= BCM2835_I2S_SYNC; + + regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, + BCM2835_I2S_SYNC, ~syncval); + + /* Wait for the SYNC flag changing it's state */ + while (--timeout) { + regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &csreg); + if ((csreg & BCM2835_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) + bcm2835_i2s_stop_clock(dev); + + /* Restore I2S state */ + regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, + BCM2835_I2S_RXON | BCM2835_I2S_TXON, i2s_active_state); +} + +static int bcm2835_i2s_set_dai_fmt(struct snd_soc_dai *dai, + unsigned int fmt) +{ + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + dev->fmt = fmt; + return 0; +} + +static int bcm2835_i2s_set_dai_bclk_ratio(struct snd_soc_dai *dai, + unsigned int ratio) +{ + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + dev->bclk_ratio = ratio; + return 0; +} + +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 mash = BCM2835_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, BCM2835_I2S_CS_A_REG, &csreg); + + 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; + 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 = BCM2835_CLK_SRC_OSC; + mash = BCM2835_CLK_MASH_0; + + if (bcm2835_clk_freq[clk_src] % target_frequency == 0 + && bit_master && frame_master) { + divi = bcm2835_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 = BCM2835_CLK_SRC_PLLD; + mash = BCM2835_CLK_MASH_1; + + dividend = bcm2835_clk_freq[clk_src]; + dividend <<= BCM2835_CLK_SHIFT; + do_div(dividend, target_frequency); + divi = dividend >> BCM2835_CLK_SHIFT; + divf = dividend & BCM2835_CLK_DIVF_MASK; + } + + /* Set clock divider */ + regmap_write(dev->clk_regmap, BCM2835_CLK_PCMDIV_REG, BCM2835_CLK_PASSWD + | BCM2835_CLK_DIVI(divi) + | BCM2835_CLK_DIVF(divf)); + + /* Setup clock, but don't start it yet */ + regmap_write(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, BCM2835_CLK_PASSWD + | BCM2835_CLK_MASH(mash) + | BCM2835_CLK_SRC(clk_src)); + + /* Setup the frame format */ + format = BCM2835_I2S_CHEN; + + if (data_length > 24) + format |= BCM2835_I2S_CHWEX; + + format |= BCM2835_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 = 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; + } + + /* + * 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, BCM2835_I2S_RXC_A_REG, format); + regmap_write(dev->i2s_regmap, BCM2835_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 |= BCM2835_I2S_FTXP | BCM2835_I2S_FRXP; + } + + mode |= BCM2835_I2S_FLEN(bclk_ratio - 1); + mode |= BCM2835_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 |= BCM2835_I2S_CLKM; + break; + case SND_SOC_DAIFMT_CBS_CFM: + /* + * CODEC is frame master + * CPU is bit clock master + */ + mode |= BCM2835_I2S_FSM; + break; + case SND_SOC_DAIFMT_CBM_CFM: + /* CODEC is master */ + mode |= BCM2835_I2S_CLKM; + mode |= BCM2835_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 |= BCM2835_I2S_CLKI; + mode |= BCM2835_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 |= BCM2835_I2S_CLKI; + break; + case SND_SOC_DAIFMT_IB_NF: + /* + * Invert only bit clock. Therefore, + * invert only frame sync for BCM + */ + mode |= BCM2835_I2S_FSI; + break; + default: + return -EINVAL; + } + + regmap_write(dev->i2s_regmap, BCM2835_I2S_MODE_A_REG, mode); + + /* Setup the DMA parameters */ + regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, + BCM2835_I2S_RXTHR(1) + | BCM2835_I2S_TXTHR(1) + | BCM2835_I2S_DMAEN, 0xffffffff); + + regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_DREQ_A_REG, + BCM2835_I2S_TX_PANIC(0x10) + | BCM2835_I2S_RX_PANIC(0x30) + | BCM2835_I2S_TX(0x30) + | BCM2835_I2S_RX(0x20), 0xffffffff); + + /* Clear FIFOs */ + bcm2835_i2s_clear_fifos(dev, true, true); + + return 0; +} + +static int bcm2835_i2s_prepare(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + uint32_t cs_reg; + + bcm2835_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, BCM2835_I2S_CS_A_REG, &cs_reg); + + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK + && !(cs_reg & BCM2835_I2S_TXE)) + bcm2835_i2s_clear_fifos(dev, true, false); + else if (substream->stream == SNDRV_PCM_STREAM_CAPTURE + && (cs_reg & BCM2835_I2S_RXD)) + bcm2835_i2s_clear_fifos(dev, false, true); + + return 0; +} + +static void bcm2835_i2s_stop(struct bcm2835_i2s_dev *dev, + struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + uint32_t mask; + + if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) + mask = BCM2835_I2S_RXON; + else + mask = BCM2835_I2S_TXON; + + regmap_update_bits(dev->i2s_regmap, + BCM2835_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)) + bcm2835_i2s_stop_clock(dev); +} + +static int bcm2835_i2s_trigger(struct snd_pcm_substream *substream, int cmd, + struct snd_soc_dai *dai) +{ + struct bcm2835_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: + bcm2835_i2s_start_clock(dev); + + if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) + mask = BCM2835_I2S_RXON; + else + mask = BCM2835_I2S_TXON; + + regmap_update_bits(dev->i2s_regmap, + BCM2835_I2S_CS_A_REG, mask, mask); + break; + + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + bcm2835_i2s_stop(dev, substream, dai); + break; + default: + return -EINVAL; + } + + return 0; +} + +static int bcm2835_i2s_startup(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + + if (dai->active) + return 0; + + /* Should this still be running stop it */ + bcm2835_i2s_stop_clock(dev); + + /* Enable PCM block */ + regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, + BCM2835_I2S_EN, BCM2835_I2S_EN); + + /* + * Disable STBY. + * Requires at least 4 PCM clock cycles to take effect. + */ + regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, + BCM2835_I2S_STBY, BCM2835_I2S_STBY); + + return 0; +} + +static void bcm2835_i2s_shutdown(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + + bcm2835_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, BCM2835_I2S_CS_A_REG, + BCM2835_I2S_EN, 0); + + /* + * Stopping clock is necessary, because stop does + * not stop the clock when SND_SOC_DAIFMT_CONT + */ + bcm2835_i2s_stop_clock(dev); +} + +static const struct snd_soc_dai_ops bcm2835_i2s_dai_ops = { + .startup = bcm2835_i2s_startup, + .shutdown = bcm2835_i2s_shutdown, + .prepare = bcm2835_i2s_prepare, + .trigger = bcm2835_i2s_trigger, + .hw_params = bcm2835_i2s_hw_params, + .set_fmt = bcm2835_i2s_set_dai_fmt, + .set_bclk_ratio = bcm2835_i2s_set_dai_bclk_ratio +}; + +static int bcm2835_i2s_dai_probe(struct snd_soc_dai *dai) +{ + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + + snd_soc_dai_init_dma_data(dai, + &dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK], + &dev->dma_data[SNDRV_PCM_STREAM_CAPTURE]); + + return 0; +} + +static struct snd_soc_dai_driver bcm2835_i2s_dai = { + .name = "bcm2835-i2s", + .probe = bcm2835_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 = &bcm2835_i2s_dai_ops, + .symmetric_rates = 1 +}; + +static bool bcm2835_i2s_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case BCM2835_I2S_CS_A_REG: + case BCM2835_I2S_FIFO_A_REG: + case BCM2835_I2S_INTSTC_A_REG: + case BCM2835_I2S_GRAY_REG: + return true; + default: + return false; + }; +} + +static bool bcm2835_i2s_precious_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case BCM2835_I2S_FIFO_A_REG: + return true; + default: + return false; + }; +} + +static bool bcm2835_clk_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case BCM2835_CLK_PCMCTL_REG: + return true; + default: + return false; + }; +} + +static const struct regmap_config bcm2835_regmap_config[] = { + { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .max_register = BCM2835_I2S_GRAY_REG, + .precious_reg = bcm2835_i2s_precious_reg, + .volatile_reg = bcm2835_i2s_volatile_reg, + .cache_type = REGCACHE_RBTREE, + }, + { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .max_register = BCM2835_CLK_PCMDIV_REG, + .volatile_reg = bcm2835_clk_volatile_reg, + .cache_type = REGCACHE_RBTREE, + }, +}; + +static const struct snd_soc_component_driver bcm2835_i2s_component = { + .name = "bcm2835-i2s-comp", +}; + +static int bcm2835_i2s_probe(struct platform_device *pdev) +{ + struct bcm2835_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, + &bcm2835_regmap_config[i]); + if (IS_ERR(regmap[i])) + return PTR_ERR(regmap[i]); + } + + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), + GFP_KERNEL); + if (!dev) + return -ENOMEM; + + 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)mem[0]->start + BCM2835_I2S_FIFO_A_REG + + BCM2835_VCMMU_SHIFT; + + dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr = + (dma_addr_t)mem[0]->start + BCM2835_I2S_FIFO_A_REG + + BCM2835_VCMMU_SHIFT; + + /* 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 = devm_snd_soc_register_component(&pdev->dev, + &bcm2835_i2s_component, &bcm2835_i2s_dai, 1); + if (ret) { + dev_err(&pdev->dev, "Could not register DAI: %d\n", ret); + return ret; + } + + ret = snd_dmaengine_pcm_register(&pdev->dev, NULL, 0); + if (ret) { + dev_err(&pdev->dev, "Could not register PCM: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct of_device_id bcm2835_i2s_of_match[] = { + { .compatible = "brcm,bcm2835-i2s", }, + {}, +}; + +static int bcm2835_i2s_remove(struct platform_device *pdev) +{ + snd_dmaengine_pcm_unregister(&pdev->dev); + return 0; +} + +static struct platform_driver bcm2835_i2s_driver = { + .probe = bcm2835_i2s_probe, + .remove = bcm2835_i2s_remove, + .driver = { + .name = "bcm2835-i2s", + .owner = THIS_MODULE, + .of_match_table = bcm2835_i2s_of_match, + }, +}; + +module_platform_driver(bcm2835_i2s_driver); + +MODULE_ALIAS("platform:bcm2835-i2s"); +MODULE_DESCRIPTION("BCM2835 I2S interface"); +MODULE_AUTHOR("Florian Meier <florian.meier@koalo.de>"); +MODULE_LICENSE("GPL v2"); |