932 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			932 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
 | |
| /*
 | |
|  * 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.
 | |
|  */
 | |
| 
 | |
| #include <linux/bitops.h>
 | |
| #include <linux/clk.h>
 | |
| #include <linux/delay.h>
 | |
| #include <linux/device.h>
 | |
| #include <linux/init.h>
 | |
| #include <linux/io.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/of_address.h>
 | |
| #include <linux/slab.h>
 | |
| 
 | |
| #include <sound/core.h>
 | |
| #include <sound/dmaengine_pcm.h>
 | |
| #include <sound/initval.h>
 | |
| #include <sound/pcm.h>
 | |
| #include <sound/pcm_params.h>
 | |
| #include <sound/soc.h>
 | |
| 
 | |
| /* 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_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)
 | |
| #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)
 | |
| 
 | |
| /* 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				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;
 | |
| 	bool					clk_prepared;
 | |
| 	int					clk_rate;
 | |
| };
 | |
| 
 | |
| static void bcm2835_i2s_start_clock(struct bcm2835_i2s_dev *dev)
 | |
| {
 | |
| 	unsigned int provider = dev->fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK;
 | |
| 
 | |
| 	if (dev->clk_prepared)
 | |
| 		return;
 | |
| 
 | |
| 	switch (provider) {
 | |
| 	case SND_SOC_DAIFMT_BP_FP:
 | |
| 	case SND_SOC_DAIFMT_BP_FC:
 | |
| 		clk_prepare_enable(dev->clk);
 | |
| 		dev->clk_prepared = true;
 | |
| 		break;
 | |
| 	default:
 | |
| 		break;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void bcm2835_i2s_stop_clock(struct bcm2835_i2s_dev *dev)
 | |
| {
 | |
| 	if (dev->clk_prepared)
 | |
| 		clk_disable_unprepare(dev->clk);
 | |
| 	dev->clk_prepared = false;
 | |
| }
 | |
| 
 | |
| 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;
 | |
| 	bool clk_was_prepared;
 | |
| 	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);
 | |
| 
 | |
| 	/* Start clock if not running */
 | |
| 	clk_was_prepared = dev->clk_prepared;
 | |
| 	if (!clk_was_prepared)
 | |
| 		bcm2835_i2s_start_clock(dev);
 | |
| 
 | |
| 	/* 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_was_prepared)
 | |
| 		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);
 | |
| 
 | |
| 	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 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;
 | |
| 	bool bit_clock_provider = false;
 | |
| 	bool frame_sync_provider = false;
 | |
| 	bool frame_start_falling_edge = false;
 | |
| 	uint32_t csreg;
 | |
| 	int ret = 0;
 | |
| 
 | |
| 	/*
 | |
| 	 * 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;
 | |
| 
 | |
| 	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;
 | |
| 	}
 | |
| 
 | |
| 	/* Check if data fits into slots */
 | |
| 	if (data_length > slot_width)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	/* Check if CPU is bit clock provider */
 | |
| 	switch (dev->fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
 | |
| 	case SND_SOC_DAIFMT_BP_FP:
 | |
| 	case SND_SOC_DAIFMT_BP_FC:
 | |
| 		bit_clock_provider = true;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_BC_FP:
 | |
| 	case SND_SOC_DAIFMT_BC_FC:
 | |
| 		bit_clock_provider = false;
 | |
| 		break;
 | |
| 	default:
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	/* Check if CPU is frame sync provider */
 | |
| 	switch (dev->fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
 | |
| 	case SND_SOC_DAIFMT_BP_FP:
 | |
| 	case SND_SOC_DAIFMT_BC_FP:
 | |
| 		frame_sync_provider = true;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_BP_FC:
 | |
| 	case SND_SOC_DAIFMT_BC_FC:
 | |
| 		frame_sync_provider = false;
 | |
| 		break;
 | |
| 	default:
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	/* Clock should only be set up here if CPU is clock master */
 | |
| 	if (bit_clock_provider &&
 | |
| 	    (!dev->clk_prepared || dev->clk_rate != bclk_rate)) {
 | |
| 		if (dev->clk_prepared)
 | |
| 			bcm2835_i2s_stop_clock(dev);
 | |
| 
 | |
| 		if (dev->clk_rate != bclk_rate) {
 | |
| 			ret = clk_set_rate(dev->clk, bclk_rate);
 | |
| 			if (ret)
 | |
| 				return ret;
 | |
| 			dev->clk_rate = bclk_rate;
 | |
| 		}
 | |
| 
 | |
| 		bcm2835_i2s_start_clock(dev);
 | |
| 	}
 | |
| 
 | |
| 	/* Setup the frame format */
 | |
| 	format = BCM2835_I2S_CHEN;
 | |
| 
 | |
| 	if (data_length >= 24)
 | |
| 		format |= BCM2835_I2S_CHWEX;
 | |
| 
 | |
| 	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;
 | |
| 		frame_start_falling_edge = true;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_LEFT_J:
 | |
| 		if (slots & 1)
 | |
| 			return -EINVAL;
 | |
| 
 | |
| 		odd_slot_offset = slots >> 1;
 | |
| 		data_delay = 0;
 | |
| 		framesync_length = frame_length / 2;
 | |
| 		frame_start_falling_edge = false;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_RIGHT_J:
 | |
| 		if (slots & 1)
 | |
| 			return -EINVAL;
 | |
| 
 | |
| 		/* Odd frame lengths aren't supported */
 | |
| 		if (frame_length & 1)
 | |
| 			return -EINVAL;
 | |
| 
 | |
| 		odd_slot_offset = slots >> 1;
 | |
| 		data_delay = slot_width - data_length;
 | |
| 		framesync_length = frame_length / 2;
 | |
| 		frame_start_falling_edge = false;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_DSP_A:
 | |
| 		data_delay = 1;
 | |
| 		framesync_length = 1;
 | |
| 		frame_start_falling_edge = false;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_DSP_B:
 | |
| 		data_delay = 0;
 | |
| 		framesync_length = 1;
 | |
| 		frame_start_falling_edge = false;
 | |
| 		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);
 | |
| 
 | |
| 	/*
 | |
| 	 * Transmitting data immediately after frame start, eg
 | |
| 	 * in left-justified or DSP mode A, only works stable
 | |
| 	 * if bcm2835 is the frame clock provider.
 | |
| 	 */
 | |
| 	if ((!rx_ch1_pos || !tx_ch1_pos) && !frame_sync_provider)
 | |
| 		dev_warn(dev->dev,
 | |
| 			"Unstable consumer config detected, L/R may be swapped");
 | |
| 
 | |
| 	/*
 | |
| 	 * 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
 | |
| 		| 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 */
 | |
| 
 | |
| 	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(frame_length - 1);
 | |
| 	mode |= BCM2835_I2S_FSLEN(framesync_length);
 | |
| 
 | |
| 	/* CLKM selects bcm2835 clock slave mode */
 | |
| 	if (!bit_clock_provider)
 | |
| 		mode |= BCM2835_I2S_CLKM;
 | |
| 
 | |
| 	/* FSM selects bcm2835 frame sync slave mode */
 | |
| 	if (!frame_sync_provider)
 | |
| 		mode |= BCM2835_I2S_FSM;
 | |
| 
 | |
| 	/* CLKI selects normal clocking mode, sampling on rising edge */
 | |
|         switch (dev->fmt & SND_SOC_DAIFMT_INV_MASK) {
 | |
| 	case SND_SOC_DAIFMT_NB_NF:
 | |
| 	case SND_SOC_DAIFMT_NB_IF:
 | |
| 		mode |= BCM2835_I2S_CLKI;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_IB_NF:
 | |
| 	case SND_SOC_DAIFMT_IB_IF:
 | |
| 		break;
 | |
| 	default:
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	/* FSI selects frame start on falling edge */
 | |
| 	switch (dev->fmt & SND_SOC_DAIFMT_INV_MASK) {
 | |
| 	case SND_SOC_DAIFMT_NB_NF:
 | |
| 	case SND_SOC_DAIFMT_IB_NF:
 | |
| 		if (frame_start_falling_edge)
 | |
| 			mode |= BCM2835_I2S_FSI;
 | |
| 		break;
 | |
| 	case SND_SOC_DAIFMT_NB_IF:
 | |
| 	case SND_SOC_DAIFMT_IB_IF:
 | |
| 		if (!frame_start_falling_edge)
 | |
| 			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);
 | |
| 
 | |
| 	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);
 | |
| 
 | |
| 	dev_dbg(dev->dev, "CLKM: %d CLKI: %d FSM: %d FSI: %d frame start: %s edge\n",
 | |
| 		!!(mode & BCM2835_I2S_CLKM),
 | |
| 		!!(mode & BCM2835_I2S_CLKI),
 | |
| 		!!(mode & BCM2835_I2S_FSM),
 | |
| 		!!(mode & BCM2835_I2S_FSI),
 | |
| 		(mode & BCM2835_I2S_FSI) ? "falling" : "rising");
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| 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;
 | |
| 
 | |
| 	/*
 | |
| 	 * 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 (!snd_soc_dai_active(dai) && !(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 (snd_soc_dai_active(dai))
 | |
| 		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 (snd_soc_dai_active(dai))
 | |
| 		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,
 | |
| 	.set_tdm_slot	= bcm2835_i2s_set_dai_tdm_slot,
 | |
| };
 | |
| 
 | |
| 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_CONTINUOUS,
 | |
| 		.rate_min =	8000,
 | |
| 		.rate_max =	384000,
 | |
| 		.formats =	SNDRV_PCM_FMTBIT_S16_LE
 | |
| 				| SNDRV_PCM_FMTBIT_S24_LE
 | |
| 				| SNDRV_PCM_FMTBIT_S32_LE
 | |
| 		},
 | |
| 	.capture = {
 | |
| 		.channels_min = 2,
 | |
| 		.channels_max = 2,
 | |
| 		.rates =	SNDRV_PCM_RATE_CONTINUOUS,
 | |
| 		.rate_min =	8000,
 | |
| 		.rate_max =	384000,
 | |
| 		.formats =	SNDRV_PCM_FMTBIT_S16_LE
 | |
| 				| SNDRV_PCM_FMTBIT_S24_LE
 | |
| 				| SNDRV_PCM_FMTBIT_S32_LE
 | |
| 		},
 | |
| 	.ops = &bcm2835_i2s_dai_ops,
 | |
| 	.symmetric_rate = 1,
 | |
| 	.symmetric_sample_bits = 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 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,
 | |
| };
 | |
| 
 | |
| static const struct snd_soc_component_driver bcm2835_i2s_component = {
 | |
| 	.name			= "bcm2835-i2s-comp",
 | |
| 	.legacy_dai_naming	= 1,
 | |
| };
 | |
| 
 | |
| static int bcm2835_i2s_probe(struct platform_device *pdev)
 | |
| {
 | |
| 	struct bcm2835_i2s_dev *dev;
 | |
| 	int ret;
 | |
| 	void __iomem *base;
 | |
| 	const __be32 *addr;
 | |
| 	dma_addr_t dma_base;
 | |
| 
 | |
| 	dev = devm_kzalloc(&pdev->dev, sizeof(*dev),
 | |
| 			   GFP_KERNEL);
 | |
| 	if (!dev)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	/* get the clock */
 | |
| 	dev->clk_prepared = false;
 | |
| 	dev->clk = devm_clk_get(&pdev->dev, NULL);
 | |
| 	if (IS_ERR(dev->clk))
 | |
| 		return dev_err_probe(&pdev->dev, PTR_ERR(dev->clk),
 | |
| 				     "could not get clk\n");
 | |
| 
 | |
| 	/* Request ioarea */
 | |
| 	base = devm_platform_ioremap_resource(pdev, 0);
 | |
| 	if (IS_ERR(base))
 | |
| 		return PTR_ERR(base);
 | |
| 
 | |
| 	dev->i2s_regmap = devm_regmap_init_mmio(&pdev->dev, base,
 | |
| 				&bcm2835_regmap_config);
 | |
| 	if (IS_ERR(dev->i2s_regmap))
 | |
| 		return PTR_ERR(dev->i2s_regmap);
 | |
| 
 | |
| 	/* Set the DMA address - we have to parse DT ourselves */
 | |
| 	addr = of_get_address(pdev->dev.of_node, 0, NULL, NULL);
 | |
| 	if (!addr) {
 | |
| 		dev_err(&pdev->dev, "could not get DMA-register address\n");
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 	dma_base = be32_to_cpup(addr);
 | |
| 
 | |
| 	dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr =
 | |
| 		dma_base + BCM2835_I2S_FIFO_A_REG;
 | |
| 
 | |
| 	dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr =
 | |
| 		dma_base + BCM2835_I2S_FIFO_A_REG;
 | |
| 
 | |
| 	/* 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;
 | |
| 
 | |
| 	/*
 | |
| 	 * Set the PACK flag to enable S16_LE support (2 S16_LE values
 | |
| 	 * packed into 32-bit transfers).
 | |
| 	 */
 | |
| 	dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].flags =
 | |
| 		SND_DMAENGINE_PCM_DAI_FLAG_PACK;
 | |
| 	dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].flags =
 | |
| 		SND_DMAENGINE_PCM_DAI_FLAG_PACK;
 | |
| 
 | |
| 	/* 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 = devm_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", },
 | |
| 	{},
 | |
| };
 | |
| 
 | |
| MODULE_DEVICE_TABLE(of, bcm2835_i2s_of_match);
 | |
| 
 | |
| static struct platform_driver bcm2835_i2s_driver = {
 | |
| 	.probe		= bcm2835_i2s_probe,
 | |
| 	.driver		= {
 | |
| 		.name	= "bcm2835-i2s",
 | |
| 		.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");
 |