// SPDX-License-Identifier: GPL-2.0-only
/*
 *  ALSA PCM device for the
 *  ALSA interface to cobalt PCM capture streams
 *
 *  Copyright 2014-2015 Cisco Systems, Inc. and/or its affiliates.
 *  All rights reserved.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/delay.h>

#include <media/v4l2-device.h>

#include <sound/core.h>
#include <sound/pcm.h>

#include "cobalt-driver.h"
#include "cobalt-alsa.h"
#include "cobalt-alsa-pcm.h"

static unsigned int pcm_debug;
module_param(pcm_debug, int, 0644);
MODULE_PARM_DESC(pcm_debug, "enable debug messages for pcm");

#define dprintk(fmt, arg...) \
        do { \
                if (pcm_debug) \
                        pr_info("cobalt-alsa-pcm %s: " fmt, __func__, ##arg); \
        } while (0)

static const struct snd_pcm_hardware snd_cobalt_hdmi_capture = {
        .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
                SNDRV_PCM_INFO_MMAP           |
                SNDRV_PCM_INFO_INTERLEAVED    |
                SNDRV_PCM_INFO_MMAP_VALID,

        .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,

        .rates = SNDRV_PCM_RATE_48000,

        .rate_min = 48000,
        .rate_max = 48000,
        .channels_min = 1,
        .channels_max = 8,
        .buffer_bytes_max = 4 * 240 * 8 * 4,    /* 5 ms of data */
        .period_bytes_min = 1920,               /* 1 sample = 8 * 4 bytes */
        .period_bytes_max = 240 * 8 * 4,        /* 5 ms of 8 channel data */
        .periods_min = 1,
        .periods_max = 4,
};

static const struct snd_pcm_hardware snd_cobalt_playback = {
        .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
                SNDRV_PCM_INFO_MMAP           |
                SNDRV_PCM_INFO_INTERLEAVED    |
                SNDRV_PCM_INFO_MMAP_VALID,

        .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,

        .rates = SNDRV_PCM_RATE_48000,

        .rate_min = 48000,
        .rate_max = 48000,
        .channels_min = 1,
        .channels_max = 8,
        .buffer_bytes_max = 4 * 240 * 8 * 4,    /* 5 ms of data */
        .period_bytes_min = 1920,               /* 1 sample = 8 * 4 bytes */
        .period_bytes_max = 240 * 8 * 4,        /* 5 ms of 8 channel data */
        .periods_min = 1,
        .periods_max = 4,
};

static void sample_cpy(u8 *dst, const u8 *src, u32 len, bool is_s32)
{
        static const unsigned map[8] = { 0, 1, 5, 4, 2, 3, 6, 7 };
        unsigned idx = 0;

        while (len >= (is_s32 ? 4 : 2)) {
                unsigned offset = map[idx] * 4;
                u32 val = src[offset + 1] + (src[offset + 2] << 8) +
                         (src[offset + 3] << 16);

                if (is_s32) {
                        *dst++ = 0;
                        *dst++ = val & 0xff;
                }
                *dst++ = (val >> 8) & 0xff;
                *dst++ = (val >> 16) & 0xff;
                len -= is_s32 ? 4 : 2;
                idx++;
        }
}

static void cobalt_alsa_announce_pcm_data(struct snd_cobalt_card *cobsc,
                                        u8 *pcm_data,
                                        size_t skip,
                                        size_t samples)
{
        struct snd_pcm_substream *substream;
        struct snd_pcm_runtime *runtime;
        unsigned long flags;
        unsigned int oldptr;
        unsigned int stride;
        int length = samples;
        int period_elapsed = 0;
        bool is_s32;

        dprintk("cobalt alsa announce ptr=%p data=%p num_bytes=%zd\n", cobsc,
                pcm_data, samples);

        substream = cobsc->capture_pcm_substream;
        if (substream == NULL) {
                dprintk("substream was NULL\n");
                return;
        }

        runtime = substream->runtime;
        if (runtime == NULL) {
                dprintk("runtime was NULL\n");
                return;
        }
        is_s32 = runtime->format == SNDRV_PCM_FORMAT_S32_LE;

        stride = runtime->frame_bits >> 3;
        if (stride == 0) {
                dprintk("stride is zero\n");
                return;
        }

        if (length == 0) {
                dprintk("%s: length was zero\n", __func__);
                return;
        }

        if (runtime->dma_area == NULL) {
                dprintk("dma area was NULL - ignoring\n");
                return;
        }

        oldptr = cobsc->hwptr_done_capture;
        if (oldptr + length >= runtime->buffer_size) {
                unsigned int cnt = runtime->buffer_size - oldptr;
                unsigned i;

                for (i = 0; i < cnt; i++)
                        sample_cpy(runtime->dma_area + (oldptr + i) * stride,
                                        pcm_data + i * skip,
                                        stride, is_s32);
                for (i = cnt; i < length; i++)
                        sample_cpy(runtime->dma_area + (i - cnt) * stride,
                                        pcm_data + i * skip, stride, is_s32);
        } else {
                unsigned i;

                for (i = 0; i < length; i++)
                        sample_cpy(runtime->dma_area + (oldptr + i) * stride,
                                        pcm_data + i * skip,
                                        stride, is_s32);
        }
        snd_pcm_stream_lock_irqsave(substream, flags);

        cobsc->hwptr_done_capture += length;
        if (cobsc->hwptr_done_capture >=
            runtime->buffer_size)
                cobsc->hwptr_done_capture -=
                        runtime->buffer_size;

        cobsc->capture_transfer_done += length;
        if (cobsc->capture_transfer_done >=
            runtime->period_size) {
                cobsc->capture_transfer_done -=
                        runtime->period_size;
                period_elapsed = 1;
        }

        snd_pcm_stream_unlock_irqrestore(substream, flags);

        if (period_elapsed)
                snd_pcm_period_elapsed(substream);
}

static int alsa_fnc(struct vb2_buffer *vb, void *priv)
{
        struct cobalt_stream *s = priv;
        unsigned char *p = vb2_plane_vaddr(vb, 0);
        int i;

        if (pcm_debug) {
                pr_info("alsa: ");
                for (i = 0; i < 8 * 4; i++) {
                        if (!(i & 3))
                                pr_cont(" ");
                        pr_cont("%02x", p[i]);
                }
                pr_cont("\n");
        }
        cobalt_alsa_announce_pcm_data(s->alsa,
                        vb2_plane_vaddr(vb, 0),
                        8 * 4,
                        vb2_get_plane_payload(vb, 0) / (8 * 4));
        return 0;
}

static int snd_cobalt_pcm_capture_open(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);
        struct cobalt_stream *s = cobsc->s;

        runtime->hw = snd_cobalt_hdmi_capture;
        snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
        cobsc->capture_pcm_substream = substream;
        runtime->private_data = s;
        cobsc->alsa_record_cnt++;
        if (cobsc->alsa_record_cnt == 1) {
                int rc;

                rc = vb2_thread_start(&s->q, alsa_fnc, s, s->vdev.name);
                if (rc) {
                        cobsc->alsa_record_cnt--;
                        return rc;
                }
        }
        return 0;
}

static int snd_cobalt_pcm_capture_close(struct snd_pcm_substream *substream)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);
        struct cobalt_stream *s = cobsc->s;

        cobsc->alsa_record_cnt--;
        if (cobsc->alsa_record_cnt == 0)
                vb2_thread_stop(&s->q);
        return 0;
}

static int snd_cobalt_pcm_prepare(struct snd_pcm_substream *substream)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);

        cobsc->hwptr_done_capture = 0;
        cobsc->capture_transfer_done = 0;

        return 0;
}

static int snd_cobalt_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_STOP:
                return 0;
        default:
                return -EINVAL;
        }
        return 0;
}

static
snd_pcm_uframes_t snd_cobalt_pcm_pointer(struct snd_pcm_substream *substream)
{
        snd_pcm_uframes_t hwptr_done;
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);

        hwptr_done = cobsc->hwptr_done_capture;

        return hwptr_done;
}

static void pb_sample_cpy(u8 *dst, const u8 *src, u32 len, bool is_s32)
{
        static const unsigned map[8] = { 0, 1, 5, 4, 2, 3, 6, 7 };
        unsigned idx = 0;

        while (len >= (is_s32 ? 4 : 2)) {
                unsigned offset = map[idx] * 4;
                u8 *out = dst + offset;

                *out++ = 0;
                if (is_s32) {
                        src++;
                        *out++ = *src++;
                } else {
                        *out++ = 0;
                }
                *out++ = *src++;
                *out = *src++;
                len -= is_s32 ? 4 : 2;
                idx++;
        }
}

static void cobalt_alsa_pb_pcm_data(struct snd_cobalt_card *cobsc,
                                        u8 *pcm_data,
                                        size_t skip,
                                        size_t samples)
{
        struct snd_pcm_substream *substream;
        struct snd_pcm_runtime *runtime;
        unsigned long flags;
        unsigned int pos;
        unsigned int stride;
        bool is_s32;
        unsigned i;

        dprintk("cobalt alsa pb ptr=%p data=%p samples=%zd\n", cobsc,
                pcm_data, samples);

        substream = cobsc->playback_pcm_substream;
        if (substream == NULL) {
                dprintk("substream was NULL\n");
                return;
        }

        runtime = substream->runtime;
        if (runtime == NULL) {
                dprintk("runtime was NULL\n");
                return;
        }

        is_s32 = runtime->format == SNDRV_PCM_FORMAT_S32_LE;
        stride = runtime->frame_bits >> 3;
        if (stride == 0) {
                dprintk("stride is zero\n");
                return;
        }

        if (samples == 0) {
                dprintk("%s: samples was zero\n", __func__);
                return;
        }

        if (runtime->dma_area == NULL) {
                dprintk("dma area was NULL - ignoring\n");
                return;
        }

        pos = cobsc->pb_pos % cobsc->pb_size;
        for (i = 0; i < cobsc->pb_count / (8 * 4); i++)
                pb_sample_cpy(pcm_data + i * skip,
                                runtime->dma_area + pos + i * stride,
                                stride, is_s32);
        snd_pcm_stream_lock_irqsave(substream, flags);

        cobsc->pb_pos += i * stride;

        snd_pcm_stream_unlock_irqrestore(substream, flags);
        if (cobsc->pb_pos % cobsc->pb_count == 0)
                snd_pcm_period_elapsed(substream);
}

static int alsa_pb_fnc(struct vb2_buffer *vb, void *priv)
{
        struct cobalt_stream *s = priv;

        if (s->alsa->alsa_pb_channel)
                cobalt_alsa_pb_pcm_data(s->alsa,
                                vb2_plane_vaddr(vb, 0),
                                8 * 4,
                                vb2_get_plane_payload(vb, 0) / (8 * 4));
        return 0;
}

static int snd_cobalt_pcm_playback_open(struct snd_pcm_substream *substream)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct cobalt_stream *s = cobsc->s;

        runtime->hw = snd_cobalt_playback;
        snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
        cobsc->playback_pcm_substream = substream;
        runtime->private_data = s;
        cobsc->alsa_playback_cnt++;
        if (cobsc->alsa_playback_cnt == 1) {
                int rc;

                rc = vb2_thread_start(&s->q, alsa_pb_fnc, s, s->vdev.name);
                if (rc) {
                        cobsc->alsa_playback_cnt--;
                        return rc;
                }
        }

        return 0;
}

static int snd_cobalt_pcm_playback_close(struct snd_pcm_substream *substream)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);
        struct cobalt_stream *s = cobsc->s;

        cobsc->alsa_playback_cnt--;
        if (cobsc->alsa_playback_cnt == 0)
                vb2_thread_stop(&s->q);
        return 0;
}

static int snd_cobalt_pcm_pb_prepare(struct snd_pcm_substream *substream)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);

        cobsc->pb_size = snd_pcm_lib_buffer_bytes(substream);
        cobsc->pb_count = snd_pcm_lib_period_bytes(substream);
        cobsc->pb_pos = 0;

        return 0;
}

static int snd_cobalt_pcm_pb_trigger(struct snd_pcm_substream *substream,
                                     int cmd)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                if (cobsc->alsa_pb_channel)
                        return -EBUSY;
                cobsc->alsa_pb_channel = true;
                return 0;
        case SNDRV_PCM_TRIGGER_STOP:
                cobsc->alsa_pb_channel = false;
                return 0;
        default:
                return -EINVAL;
        }
}

static
snd_pcm_uframes_t snd_cobalt_pcm_pb_pointer(struct snd_pcm_substream *substream)
{
        struct snd_cobalt_card *cobsc = snd_pcm_substream_chip(substream);
        size_t ptr;

        ptr = cobsc->pb_pos;

        return bytes_to_frames(substream->runtime, ptr) %
               substream->runtime->buffer_size;
}

static const struct snd_pcm_ops snd_cobalt_pcm_capture_ops = {
        .open           = snd_cobalt_pcm_capture_open,
        .close          = snd_cobalt_pcm_capture_close,
        .prepare        = snd_cobalt_pcm_prepare,
        .trigger        = snd_cobalt_pcm_trigger,
        .pointer        = snd_cobalt_pcm_pointer,
};

static const struct snd_pcm_ops snd_cobalt_pcm_playback_ops = {
        .open           = snd_cobalt_pcm_playback_open,
        .close          = snd_cobalt_pcm_playback_close,
        .prepare        = snd_cobalt_pcm_pb_prepare,
        .trigger        = snd_cobalt_pcm_pb_trigger,
        .pointer        = snd_cobalt_pcm_pb_pointer,
};

int snd_cobalt_pcm_create(struct snd_cobalt_card *cobsc)
{
        struct snd_pcm *sp;
        struct snd_card *sc = cobsc->sc;
        struct cobalt_stream *s = cobsc->s;
        struct cobalt *cobalt = s->cobalt;
        int ret;

        s->q.gfp_flags |= __GFP_ZERO;

        if (!s->is_output) {
                cobalt_s_bit_sysctrl(cobalt,
                        COBALT_SYS_CTRL_AUDIO_IPP_RESETN_BIT(s->video_channel),
                        0);
                mdelay(2);
                cobalt_s_bit_sysctrl(cobalt,
                        COBALT_SYS_CTRL_AUDIO_IPP_RESETN_BIT(s->video_channel),
                        1);
                mdelay(1);

                ret = snd_pcm_new(sc, "Cobalt PCM-In HDMI",
                        0, /* PCM device 0, the only one for this card */
                        0, /* 0 playback substreams */
                        1, /* 1 capture substream */
                        &sp);
                if (ret) {
                        cobalt_err("snd_cobalt_pcm_create() failed for input with err %d\n",
                                   ret);
                        goto err_exit;
                }

                snd_pcm_set_ops(sp, SNDRV_PCM_STREAM_CAPTURE,
                                &snd_cobalt_pcm_capture_ops);
                snd_pcm_set_managed_buffer_all(sp, SNDRV_DMA_TYPE_VMALLOC,
                                               NULL, 0, 0);
                sp->info_flags = 0;
                sp->private_data = cobsc;
                strscpy(sp->name, "cobalt", sizeof(sp->name));
        } else {
                cobalt_s_bit_sysctrl(cobalt,
                        COBALT_SYS_CTRL_AUDIO_OPP_RESETN_BIT, 0);
                mdelay(2);
                cobalt_s_bit_sysctrl(cobalt,
                        COBALT_SYS_CTRL_AUDIO_OPP_RESETN_BIT, 1);
                mdelay(1);

                ret = snd_pcm_new(sc, "Cobalt PCM-Out HDMI",
                        0, /* PCM device 0, the only one for this card */
                        1, /* 0 playback substreams */
                        0, /* 1 capture substream */
                        &sp);
                if (ret) {
                        cobalt_err("snd_cobalt_pcm_create() failed for output with err %d\n",
                                   ret);
                        goto err_exit;
                }

                snd_pcm_set_ops(sp, SNDRV_PCM_STREAM_PLAYBACK,
                                &snd_cobalt_pcm_playback_ops);
                snd_pcm_set_managed_buffer_all(sp, SNDRV_DMA_TYPE_VMALLOC,
                                               NULL, 0, 0);
                sp->info_flags = 0;
                sp->private_data = cobsc;
                strscpy(sp->name, "cobalt", sizeof(sp->name));
        }

        return 0;

err_exit:
        return ret;
}