portapack-mayhem/firmware/common/i2s.hpp

/*
 * Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
 *
 * This file is part of PortaPack.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef __I2S_H__
#define __I2S_H__

#include "hal.h"

#include "utility.hpp"

namespace lpc43xx {
namespace i2s {

enum class WordWidth {
    Bits8 = 0x0,
    Bits16 = 0x1,
    Bits32 = 0x3,
};

enum class ClockSelect {
    FractionalDivider = 0x0,
    BaseAudioClkOrExternalMCLK = 0x01,
    OtherMCLK = 0x2,
};

struct DAO {
    WordWidth wordwidth;
    uint32_t mono;
    uint32_t stop;
    uint32_t reset;
    uint32_t ws_sel;
    uint32_t ws_halfperiod;
    uint32_t mute;

    constexpr operator uint32_t() const {
        return ((toUType(wordwidth) & 3) << 0) | ((mono & 1) << 2) | ((stop & 1) << 3) | ((reset & 1) << 4) | ((ws_sel & 1) << 5) | ((ws_halfperiod & 0x1ff) << 6) | ((mute & 1) << 15);
    }
};

struct DAI {
    WordWidth wordwidth;
    uint32_t mono;
    uint32_t stop;
    uint32_t reset;
    uint32_t ws_sel;
    uint32_t ws_halfperiod;

    constexpr operator uint32_t() const {
        return ((toUType(wordwidth) & 3) << 0) | ((mono & 1) << 2) | ((stop & 1) << 3) | ((reset & 1) << 4) | ((ws_sel & 1) << 5) | ((ws_halfperiod & 0x1ff) << 6);
    }
};

struct MCLKRate {
    uint32_t x_divider;
    uint32_t y_divider;

    constexpr operator uint32_t() const {
        return ((y_divider & 0xff) << 0) | ((x_divider & 0xff) << 8);
    }
};

struct BitRate {
    uint32_t bitrate;

    constexpr operator uint32_t() const {
        return ((bitrate & 0x3f) << 0);
    }
};

struct Mode {
    ClockSelect clksel;
    uint32_t four_pin;
    uint32_t mclk_out_en;

    constexpr operator uint32_t() const {
        return ((toUType(clksel) & 3) << 0) | ((four_pin & 1) << 2) | ((mclk_out_en & 1) << 3);
    }
};

struct DMA {
    uint32_t rx_enable;
    uint32_t tx_enable;
    size_t rx_depth;
    size_t tx_depth;

    constexpr operator uint32_t() const {
        return ((rx_enable & 1) << 0) | ((tx_enable & 1) << 1) | ((rx_depth & 0xf) << 8) | ((tx_depth & 0xf) << 16);
    }
};

struct ConfigTX {
    uint32_t dao;
    uint32_t txrate;
    uint32_t txbitrate;
    uint32_t txmode;
    uint32_t sck_in_sel;
};

struct ConfigRX {
    uint32_t dai;
    uint32_t rxrate;
    uint32_t rxbitrate;
    uint32_t rxmode;
    uint32_t sck_in_sel;
};

struct ConfigDMA {
    uint32_t dma1;
    uint32_t dma2;
};

static const audio_clock_resources_t audio_clock_resources = {
    .base = {.clk = &LPC_CGU->BASE_AUDIO_CLK, .stat = &LPC_CCU2->BASE_STAT, .stat_mask = 0},
    .branch = {.cfg = &LPC_CCU2->CLK_AUDIO_CFG, .stat = &LPC_CCU2->CLK_AUDIO_STAT},
};

static const i2s_resources_t i2s_resources = {
    .base = {.clk = &LPC_CGU->BASE_APB1_CLK, .stat = &LPC_CCU1->BASE_STAT, .stat_mask = (1 << 1)},
    .branch = {.cfg = &LPC_CCU1->CLK_APB1_I2S_CFG, .stat = &LPC_CCU1->CLK_APB1_I2S_STAT},
    .reset = {{.output_index = 52}, {.output_index = 53}},
};

template <uint32_t BaseAddress>
class I2S {
   public:
    static void configure(
        const ConfigTX& config_tx,
        const ConfigRX& config_rx) {
        base_clock_enable(&i2s_resources.base);
        branch_clock_enable(&i2s_resources.branch);

        base_clock_enable(&audio_clock_resources.base);
        branch_clock_enable(&audio_clock_resources.branch);

        if (&p() == LPC_I2S0) {
            peripheral_reset(&i2s_resources.reset[0]);
        }
        if (&p() == LPC_I2S1) {
            peripheral_reset(&i2s_resources.reset[1]);
        }

        reset();

        if (&p() == LPC_I2S0) {
            LPC_CREG->CREG6.I2S0_TX_SCK_IN_SEL = config_tx.sck_in_sel;
            LPC_CREG->CREG6.I2S0_RX_SCK_IN_SEL = config_rx.sck_in_sel;
        }
        if (&p() == LPC_I2S1) {
            LPC_CREG->CREG6.I2S1_TX_SCK_IN_SEL = config_tx.sck_in_sel;
            LPC_CREG->CREG6.I2S1_RX_SCK_IN_SEL = config_rx.sck_in_sel;
        }

        p().DAO = config_tx.dao;
        p().TXRATE = config_tx.txrate;
        p().TXBITRATE = config_tx.txbitrate;
        p().TXMODE = config_tx.txmode;

        p().DAI = config_rx.dai;
        p().RXRATE = config_rx.rxrate;
        p().RXBITRATE = config_rx.rxbitrate;
        p().RXMODE = config_rx.rxmode;
    }

    static void configure(
        const ConfigTX& config_tx,
        const ConfigRX& config_rx,
        const ConfigDMA& config_dma) {
        configure(config_tx, config_rx);

        p().DMA1 = config_dma.dma1;
        p().DMA2 = config_dma.dma2;
    }

    static void shutdown() {
        if (&p() == LPC_I2S0) {
            peripheral_reset(&i2s_resources.reset[0]);
        }
        if (&p() == LPC_I2S1) {
            peripheral_reset(&i2s_resources.reset[1]);
        }

        branch_clock_disable(&audio_clock_resources.branch);
        base_clock_disable(&audio_clock_resources.base);

        branch_clock_disable(&i2s_resources.branch);
        base_clock_disable(&i2s_resources.base);
    }

    static void rx_start() {
        p().DAI &= ~(1U << 3);
    }

    static void rx_stop() {
        p().DAI |= (1U << 3);
    }

    static void tx_start() {
        p().DAO &= ~(1U << 3);
    }

    static void tx_stop() {
        p().DAO |= (1U << 3);
    }

    static void tx_mute() {
        p().DAO |= (1U << 15);
    }

    static void tx_unmute() {
        p().DAO &= ~(1U << 15);
    }

   private:
    static void reset() {
        p().DAO |= (1U << 4);
        p().DAI |= (1U << 4);
    }

    static LPC_I2S_Type& p() {
        return *reinterpret_cast<LPC_I2S_Type*>(BaseAddress);
    }
};

using i2s0 = I2S<LPC_I2S0_BASE>;
using i2s1 = I2S<LPC_I2S1_BASE>;

} /* namespace i2s */
} /* namespace lpc43xx */

#endif /*__I2S_H__*/