root/sound/pci/cs5535audio/cs5535audio.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for audio on multifunction CS5535/6 companion device
 * Copyright (C) Jaya Kumar
 *
 * Based on Jaroslav Kysela and Takashi Iwai's examples.
 * This work was sponsored by CIS(M) Sdn Bhd.
 */

#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/io.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/rawmidi.h>
#include <sound/ac97_codec.h>
#include <sound/initval.h>
#include <sound/asoundef.h>
#include "cs5535audio.h"

#define DRIVER_NAME "cs5535audio"

static char *ac97_quirk;
module_param(ac97_quirk, charp, 0444);
MODULE_PARM_DESC(ac97_quirk, "AC'97 board specific workarounds.");

static const struct ac97_quirk ac97_quirks[] = {
#if 0 /* Not yet confirmed if all 5536 boards are HP only */
        {
                .subvendor = PCI_VENDOR_ID_AMD, 
                .subdevice = PCI_DEVICE_ID_AMD_CS5536_AUDIO, 
                .name = "AMD RDK",     
                .type = AC97_TUNE_HP_ONLY
        },
#endif
        {}
};

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for " DRIVER_NAME);
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for " DRIVER_NAME);
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable " DRIVER_NAME);

static const struct pci_device_id snd_cs5535audio_ids[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_AUDIO) },
        { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_AUDIO) },
        {}
};

MODULE_DEVICE_TABLE(pci, snd_cs5535audio_ids);

static void wait_till_cmd_acked(struct cs5535audio *cs5535au, unsigned long timeout)
{
        unsigned int tmp;
        do {
                tmp = cs_readl(cs5535au, ACC_CODEC_CNTL);
                if (!(tmp & CMD_NEW))
                        break;
                udelay(1);
        } while (--timeout);
        if (!timeout)
                dev_err(cs5535au->card->dev,
                        "Failure writing to cs5535 codec\n");
}

static unsigned short snd_cs5535audio_codec_read(struct cs5535audio *cs5535au,
                                                 unsigned short reg)
{
        unsigned int regdata;
        unsigned int timeout;
        unsigned int val;

        regdata = ((unsigned int) reg) << 24;
        regdata |= ACC_CODEC_CNTL_RD_CMD;
        regdata |= CMD_NEW;

        cs_writel(cs5535au, ACC_CODEC_CNTL, regdata);
        wait_till_cmd_acked(cs5535au, 50);

        timeout = 50;
        do {
                val = cs_readl(cs5535au, ACC_CODEC_STATUS);
                if ((val & STS_NEW) && reg == (val >> 24))
                        break;
                udelay(1);
        } while (--timeout);
        if (!timeout)
                dev_err(cs5535au->card->dev,
                        "Failure reading codec reg 0x%x, Last value=0x%x\n",
                        reg, val);

        return (unsigned short) val;
}

static void snd_cs5535audio_codec_write(struct cs5535audio *cs5535au,
                                        unsigned short reg, unsigned short val)
{
        unsigned int regdata;

        regdata = ((unsigned int) reg) << 24;
        regdata |= val;
        regdata &= CMD_MASK;
        regdata |= CMD_NEW;
        regdata &= ACC_CODEC_CNTL_WR_CMD;

        cs_writel(cs5535au, ACC_CODEC_CNTL, regdata);
        wait_till_cmd_acked(cs5535au, 50);
}

static void snd_cs5535audio_ac97_codec_write(struct snd_ac97 *ac97,
                                             unsigned short reg, unsigned short val)
{
        struct cs5535audio *cs5535au = ac97->private_data;
        snd_cs5535audio_codec_write(cs5535au, reg, val);
}

static unsigned short snd_cs5535audio_ac97_codec_read(struct snd_ac97 *ac97,
                                                      unsigned short reg)
{
        struct cs5535audio *cs5535au = ac97->private_data;
        return snd_cs5535audio_codec_read(cs5535au, reg);
}

static int snd_cs5535audio_mixer(struct cs5535audio *cs5535au)
{
        struct snd_card *card = cs5535au->card;
        struct snd_ac97_bus *pbus;
        struct snd_ac97_template ac97;
        int err;
        static const struct snd_ac97_bus_ops ops = {
                .write = snd_cs5535audio_ac97_codec_write,
                .read = snd_cs5535audio_ac97_codec_read,
        };

        err = snd_ac97_bus(card, 0, &ops, NULL, &pbus);
        if (err < 0)
                return err;

        memset(&ac97, 0, sizeof(ac97));
        ac97.scaps = AC97_SCAP_AUDIO | AC97_SCAP_SKIP_MODEM
                        | AC97_SCAP_POWER_SAVE;
        ac97.private_data = cs5535au;
        ac97.pci = cs5535au->pci;

        /* set any OLPC-specific scaps */
        olpc_prequirks(card, &ac97);

        err = snd_ac97_mixer(pbus, &ac97, &cs5535au->ac97);
        if (err < 0) {
                dev_err(card->dev, "mixer failed\n");
                return err;
        }

        snd_ac97_tune_hardware(cs5535au->ac97, ac97_quirks, ac97_quirk);

        err = olpc_quirks(card, cs5535au->ac97);
        if (err < 0) {
                dev_err(card->dev, "olpc quirks failed\n");
                return err;
        }

        return 0;
}

static void process_bm0_irq(struct cs5535audio *cs5535au)
{
        u8 bm_stat;

        scoped_guard(spinlock, &cs5535au->reg_lock) {
                bm_stat = cs_readb(cs5535au, ACC_BM0_STATUS);
        }
        if (bm_stat & EOP) {
                snd_pcm_period_elapsed(cs5535au->playback_substream);
        } else {
                dev_err(cs5535au->card->dev,
                        "unexpected bm0 irq src, bm_stat=%x\n",
                        bm_stat);
        }
}

static void process_bm1_irq(struct cs5535audio *cs5535au)
{
        u8 bm_stat;

        scoped_guard(spinlock, &cs5535au->reg_lock) {
                bm_stat = cs_readb(cs5535au, ACC_BM1_STATUS);
        }
        if (bm_stat & EOP)
                snd_pcm_period_elapsed(cs5535au->capture_substream);
}

static irqreturn_t snd_cs5535audio_interrupt(int irq, void *dev_id)
{
        u16 acc_irq_stat;
        unsigned char count;
        struct cs5535audio *cs5535au = dev_id;

        if (cs5535au == NULL)
                return IRQ_NONE;

        acc_irq_stat = cs_readw(cs5535au, ACC_IRQ_STATUS);

        if (!acc_irq_stat)
                return IRQ_NONE;
        for (count = 0; count < 4; count++) {
                if (acc_irq_stat & (1 << count)) {
                        switch (count) {
                        case IRQ_STS:
                                cs_readl(cs5535au, ACC_GPIO_STATUS);
                                break;
                        case WU_IRQ_STS:
                                cs_readl(cs5535au, ACC_GPIO_STATUS);
                                break;
                        case BM0_IRQ_STS:
                                process_bm0_irq(cs5535au);
                                break;
                        case BM1_IRQ_STS:
                                process_bm1_irq(cs5535au);
                                break;
                        default:
                                dev_err(cs5535au->card->dev,
                                        "Unexpected irq src: 0x%x\n",
                                        acc_irq_stat);
                                break;
                        }
                }
        }
        return IRQ_HANDLED;
}

static void snd_cs5535audio_free(struct snd_card *card)
{
        olpc_quirks_cleanup();
}

static int snd_cs5535audio_create(struct snd_card *card,
                                  struct pci_dev *pci)
{
        struct cs5535audio *cs5535au = card->private_data;
        int err;

        err = pcim_enable_device(pci);
        if (err < 0)
                return err;

        if (dma_set_mask_and_coherent(&pci->dev, DMA_BIT_MASK(32))) {
                dev_warn(card->dev, "unable to get 32bit dma\n");
                return -ENXIO;
        }

        spin_lock_init(&cs5535au->reg_lock);
        cs5535au->card = card;
        cs5535au->pci = pci;
        cs5535au->irq = -1;

        err = pcim_request_all_regions(pci, "CS5535 Audio");
        if (err < 0)
                return err;

        cs5535au->port = pci_resource_start(pci, 0);

        if (devm_request_irq(&pci->dev, pci->irq, snd_cs5535audio_interrupt,
                             IRQF_SHARED, KBUILD_MODNAME, cs5535au)) {
                dev_err(card->dev, "unable to grab IRQ %d\n", pci->irq);
                return -EBUSY;
        }

        cs5535au->irq = pci->irq;
        card->sync_irq = cs5535au->irq;
        pci_set_master(pci);

        return 0;
}

static int __snd_cs5535audio_probe(struct pci_dev *pci,
                                   const struct pci_device_id *pci_id)
{
        static int dev;
        struct snd_card *card;
        struct cs5535audio *cs5535au;
        int err;

        if (dev >= SNDRV_CARDS)
                return -ENODEV;
        if (!enable[dev]) {
                dev++;
                return -ENOENT;
        }

        err = snd_devm_card_new(&pci->dev, index[dev], id[dev], THIS_MODULE,
                                sizeof(*cs5535au), &card);
        if (err < 0)
                return err;
        cs5535au = card->private_data;
        card->private_free = snd_cs5535audio_free;

        err = snd_cs5535audio_create(card, pci);
        if (err < 0)
                return err;

        err = snd_cs5535audio_mixer(cs5535au);
        if (err < 0)
                return err;

        err = snd_cs5535audio_pcm(cs5535au);
        if (err < 0)
                return err;

        strscpy(card->driver, DRIVER_NAME);

        strscpy(card->shortname, "CS5535 Audio");
        sprintf(card->longname, "%s %s at 0x%lx, irq %i",
                card->shortname, card->driver,
                cs5535au->port, cs5535au->irq);

        err = snd_card_register(card);
        if (err < 0)
                return err;

        pci_set_drvdata(pci, card);
        dev++;
        return 0;
}

static int snd_cs5535audio_probe(struct pci_dev *pci,
                                 const struct pci_device_id *pci_id)
{
        return snd_card_free_on_error(&pci->dev, __snd_cs5535audio_probe(pci, pci_id));
}

static struct pci_driver cs5535audio_driver = {
        .name = KBUILD_MODNAME,
        .id_table = snd_cs5535audio_ids,
        .probe = snd_cs5535audio_probe,
#ifdef CONFIG_PM_SLEEP
        .driver = {
                .pm = &snd_cs5535audio_pm,
        },
#endif
};

module_pci_driver(cs5535audio_driver);

MODULE_AUTHOR("Jaya Kumar");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("CS5535 Audio");