ASoC: Intel: Add Skylake HDA audio driver

/*

 *  skl.c - Implementation of ASoC Intel SKL HD Audio driver

 *

 *  Copyright (C) 2014-2015 Intel Corp

 *  Author: Jeeja KP <jeeja.kp@intel.com>

 *

 *  Derived mostly from Intel HDA driver with following copyrights:

 *  Copyright (c) 2004 Takashi Iwai <tiwai@suse.de>

 *                     PeiSen Hou <pshou@realtek.com.tw>

 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 *

 *  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; version 2 of the License.

 *

 *  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/module.h>

#include <linux/pci.h>

#include <linux/pm_runtime.h>

#include <linux/platform_device.h>

#include <sound/pcm.h>

#include "skl.h"

/*

 * initialize the PCI registers

 */

static void skl_update_pci_byte(struct pci_dev *pci, unsigned int reg,

			    unsigned char mask, unsigned char val)

{

	unsigned char data;

	pci_read_config_byte(pci, reg, &data);

	data &= ~mask;

	data |= (val & mask);

	pci_write_config_byte(pci, reg, data);

}

static void skl_init_pci(struct skl *skl)

{

	struct hdac_ext_bus *ebus = &skl->ebus;

	/*

	 * Clear bits 0-2 of PCI register TCSEL (at offset 0x44)

	 * TCSEL == Traffic Class Select Register, which sets PCI express QOS

	 * Ensuring these bits are 0 clears playback static on some HD Audio

	 * codecs.

	 * The PCI register TCSEL is defined in the Intel manuals.

	 */

	dev_dbg(ebus_to_hbus(ebus)->dev, "Clearing TCSEL\n");

	skl_update_pci_byte(skl->pci, AZX_PCIREG_TCSEL, 0x07, 0);

}

/* called from IRQ */

static void skl_stream_update(struct hdac_bus *bus, struct hdac_stream *hstr)

{

	snd_pcm_period_elapsed(hstr->substream);

}

static irqreturn_t skl_interrupt(int irq, void *dev_id)

{

	struct hdac_ext_bus *ebus = dev_id;

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	u32 status;

	if (!pm_runtime_active(bus->dev))

		return IRQ_NONE;

	spin_lock(&bus->reg_lock);

	status = snd_hdac_chip_readl(bus, INTSTS);

	if (status == 0 || status == 0xffffffff) {

		spin_unlock(&bus->reg_lock);

		return IRQ_NONE;

	}

	/* clear rirb int */

	status = snd_hdac_chip_readb(bus, RIRBSTS);

	if (status & RIRB_INT_MASK) {

		if (status & RIRB_INT_RESPONSE)

			snd_hdac_bus_update_rirb(bus);

		snd_hdac_chip_writeb(bus, RIRBSTS, RIRB_INT_MASK);

	}

	spin_unlock(&bus->reg_lock);

	return snd_hdac_chip_readl(bus, INTSTS) ? IRQ_WAKE_THREAD : IRQ_HANDLED;

}

static irqreturn_t skl_threaded_handler(int irq, void *dev_id)

{

	struct hdac_ext_bus *ebus = dev_id;

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	u32 status;

	status = snd_hdac_chip_readl(bus, INTSTS);

	snd_hdac_bus_handle_stream_irq(bus, status, skl_stream_update);

	return IRQ_HANDLED;

}

static int skl_acquire_irq(struct hdac_ext_bus *ebus, int do_disconnect)

{

	struct skl *skl = ebus_to_skl(ebus);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	int ret;

	ret = request_threaded_irq(skl->pci->irq, skl_interrupt,

			skl_threaded_handler,

			IRQF_SHARED,

			KBUILD_MODNAME, ebus);

	if (ret) {

		dev_err(bus->dev,

			"unable to grab IRQ %d, disabling device\n",

			skl->pci->irq);

		return ret;

	}

	bus->irq = skl->pci->irq;

	pci_intx(skl->pci, 1);

	return 0;

}

#ifdef CONFIG_PM_SLEEP

/*

 * power management

 */

static int skl_suspend(struct device *dev)

{

	struct pci_dev *pci = to_pci_dev(dev);

	struct hdac_ext_bus *ebus = pci_get_drvdata(pci);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	snd_hdac_bus_stop_chip(bus);

	snd_hdac_bus_enter_link_reset(bus);

	return 0;

}

static int skl_resume(struct device *dev)

{

	struct pci_dev *pci = to_pci_dev(dev);

	struct hdac_ext_bus *ebus = pci_get_drvdata(pci);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	struct skl *hda = ebus_to_skl(ebus);

	skl_init_pci(hda);

	snd_hdac_bus_init_chip(bus, 1);

	return 0;

}

#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_PM

static int skl_runtime_suspend(struct device *dev)

{

	struct pci_dev *pci = to_pci_dev(dev);

	struct hdac_ext_bus *ebus = pci_get_drvdata(pci);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	dev_dbg(bus->dev, "in %s\n", __func__);

	/* enable controller wake up event */

	snd_hdac_chip_updatew(bus, WAKEEN, 0, STATESTS_INT_MASK);

	snd_hdac_bus_stop_chip(bus);

	snd_hdac_bus_enter_link_reset(bus);

	return 0;

}

static int skl_runtime_resume(struct device *dev)

{

	struct pci_dev *pci = to_pci_dev(dev);

	struct hdac_ext_bus *ebus = pci_get_drvdata(pci);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	struct skl *hda = ebus_to_skl(ebus);

	int status;

	dev_dbg(bus->dev, "in %s\n", __func__);

	/* Read STATESTS before controller reset */

	status = snd_hdac_chip_readw(bus, STATESTS);

	skl_init_pci(hda);

	snd_hdac_bus_init_chip(bus, true);

	/* disable controller Wake Up event */

	snd_hdac_chip_updatew(bus, WAKEEN, STATESTS_INT_MASK, 0);

	return 0;

}

#endif /* CONFIG_PM */

static const struct dev_pm_ops skl_pm = {

	SET_SYSTEM_SLEEP_PM_OPS(skl_suspend, skl_resume)

	SET_RUNTIME_PM_OPS(skl_runtime_suspend, skl_runtime_resume, NULL)

};

/*

 * destructor

 */

static int skl_free(struct hdac_ext_bus *ebus)

{

	struct skl *skl  = ebus_to_skl(ebus);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	skl->init_failed = 1; /* to be sure */

	snd_hdac_ext_stop_streams(ebus);

	if (bus->irq >= 0)

		free_irq(bus->irq, (void *)bus);

	if (bus->remap_addr)

		iounmap(bus->remap_addr);

	snd_hdac_bus_free_stream_pages(bus);

	snd_hdac_stream_free_all(ebus);

	snd_hdac_link_free_all(ebus);

	pci_release_regions(skl->pci);

	pci_disable_device(skl->pci);

	snd_hdac_ext_bus_exit(ebus);

	return 0;

}

static int skl_dmic_device_register(struct skl *skl)

{

	struct hdac_bus *bus = ebus_to_hbus(&skl->ebus);

	struct platform_device *pdev;

	int ret;

	/* SKL has one dmic port, so allocate dmic device for this */

	pdev = platform_device_alloc("dmic-codec", -1);

	if (!pdev) {

		dev_err(bus->dev, "failed to allocate dmic device\n");

		return -ENOMEM;

	}

	ret = platform_device_add(pdev);

	if (ret) {

		dev_err(bus->dev, "failed to add dmic device: %d\n", ret);

		platform_device_put(pdev);

		return ret;

	}

	skl->dmic_dev = pdev;

	return 0;

}

static void skl_dmic_device_unregister(struct skl *skl)

{

	if (skl->dmic_dev)

		platform_device_unregister(skl->dmic_dev);

}

/*

 * Probe the given codec address

 */

static int probe_codec(struct hdac_ext_bus *ebus, int addr)

{

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	unsigned int cmd = (addr << 28) | (AC_NODE_ROOT << 20) |

		(AC_VERB_PARAMETERS << 8) | AC_PAR_VENDOR_ID;

	unsigned int res;

	mutex_lock(&bus->cmd_mutex);

	snd_hdac_bus_send_cmd(bus, cmd);

	snd_hdac_bus_get_response(bus, addr, &res);

	mutex_unlock(&bus->cmd_mutex);

	if (res == -1)

		return -EIO;

	dev_dbg(bus->dev, "codec #%d probed OK\n", addr);

	return snd_hdac_ext_bus_device_init(ebus, addr);

}

/* Codec initialization */

static int skl_codec_create(struct hdac_ext_bus *ebus)

{

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	int c, max_slots;

	max_slots = HDA_MAX_CODECS;

	/* First try to probe all given codec slots */

	for (c = 0; c < max_slots; c++) {

		if ((bus->codec_mask & (1 << c))) {

			if (probe_codec(ebus, c) < 0) {

				/*

				 * Some BIOSen give you wrong codec addresses

				 * that don't exist

				 */

				dev_warn(bus->dev,

					 "Codec #%d probe error; disabling it...\n", c);

				bus->codec_mask &= ~(1 << c);

				/*

				 * More badly, accessing to a non-existing

				 * codec often screws up the controller bus,

				 * and disturbs the further communications.

				 * Thus if an error occurs during probing,

				 * better to reset the controller bus to get

				 * back to the sanity state.

				 */

				snd_hdac_bus_stop_chip(bus);

				snd_hdac_bus_init_chip(bus, true);

			}

		}

	}

	return 0;

}

static const struct hdac_bus_ops bus_core_ops = {

	.command = snd_hdac_bus_send_cmd,

	.get_response = snd_hdac_bus_get_response,

};

/*

 * constructor

 */

static int skl_create(struct pci_dev *pci,

		      const struct hdac_io_ops *io_ops,

		      struct skl **rskl)

{

	struct skl *skl;

	struct hdac_ext_bus *ebus;

	int err;

	*rskl = NULL;

	err = pci_enable_device(pci);

	if (err < 0)

		return err;

	skl = devm_kzalloc(&pci->dev, sizeof(*skl), GFP_KERNEL);

	if (!skl) {

		pci_disable_device(pci);

		return -ENOMEM;

	}

	ebus = &skl->ebus;

	snd_hdac_ext_bus_init(ebus, &pci->dev, &bus_core_ops, io_ops);

	ebus->bus.use_posbuf = 1;

	skl->pci = pci;

	ebus->bus.bdl_pos_adj = 0;

	*rskl = skl;

	return 0;

}

static int skl_first_init(struct hdac_ext_bus *ebus)

{

	struct skl *skl = ebus_to_skl(ebus);

	struct hdac_bus *bus = ebus_to_hbus(ebus);

	struct pci_dev *pci = skl->pci;

	int err;

	unsigned short gcap;

	int cp_streams, pb_streams, start_idx;

	err = pci_request_regions(pci, "Skylake HD audio");

	if (err < 0)

		return err;

	bus->addr = pci_resource_start(pci, 0);

	bus->remap_addr = pci_ioremap_bar(pci, 0);

	if (bus->remap_addr == NULL) {

		dev_err(bus->dev, "ioremap error\n");

		return -ENXIO;

	}

	if (skl_acquire_irq(ebus, 0) < 0)

		return -EBUSY;

	pci_set_master(pci);

	synchronize_irq(bus->irq);

	gcap = snd_hdac_chip_readw(bus, GCAP);

	dev_dbg(bus->dev, "chipset global capabilities = 0x%x\n", gcap);

	/* allow 64bit DMA address if supported by H/W */

	if (!dma_set_mask(bus->dev, DMA_BIT_MASK(64))) {

		dma_set_coherent_mask(bus->dev, DMA_BIT_MASK(64));

	} else {

		dma_set_mask(bus->dev, DMA_BIT_MASK(32));

		dma_set_coherent_mask(bus->dev, DMA_BIT_MASK(32));

	}

	/* read number of streams from GCAP register */

	cp_streams = (gcap >> 8) & 0x0f;

	pb_streams = (gcap >> 12) & 0x0f;

	if (!pb_streams && !cp_streams)

		return -EIO;

	ebus->num_streams = cp_streams + pb_streams;

	/* initialize streams */

	snd_hdac_ext_stream_init_all

		(ebus, 0, cp_streams, SNDRV_PCM_STREAM_CAPTURE);

	start_idx = cp_streams;

	snd_hdac_ext_stream_init_all

		(ebus, start_idx, pb_streams, SNDRV_PCM_STREAM_PLAYBACK);

	err = snd_hdac_bus_alloc_stream_pages(bus);

	if (err < 0)

		return err;

	/* initialize chip */

	skl_init_pci(skl);

	snd_hdac_bus_init_chip(bus, true);

	/* codec detection */

	if (!bus->codec_mask) {

		dev_err(bus->dev, "no codecs found!\n");

		return -ENODEV;

	}

	return 0;

}

static int skl_probe(struct pci_dev *pci,

		     const struct pci_device_id *pci_id)

{

	struct skl *skl;

	struct hdac_ext_bus *ebus = NULL;

	struct hdac_bus *bus = NULL;

	int err;

	/* we use ext core ops, so provide NULL for ops here */

	err = skl_create(pci, NULL, &skl);

	if (err < 0)

		return err;

	ebus = &skl->ebus;

	bus = ebus_to_hbus(ebus);

	err = skl_first_init(ebus);

	if (err < 0)

		goto out_free;

	pci_set_drvdata(skl->pci, ebus);

	/* create device for soc dmic */

	err = skl_dmic_device_register(skl);

	if (err < 0)

		goto out_free;

	/* register platform dai and controls */

	err = skl_platform_register(bus->dev);

	if (err < 0)

		goto out_dmic_free;

	/* create codec instances */

	err = skl_codec_create(ebus);

	if (err < 0)

		goto out_unregister;

	/*configure PM */

	pm_runtime_set_autosuspend_delay(bus->dev, SKL_SUSPEND_DELAY);

	pm_runtime_use_autosuspend(bus->dev);

	pm_runtime_put_noidle(bus->dev);

	pm_runtime_allow(bus->dev);

	return 0;

out_unregister:

	skl_platform_unregister(bus->dev);

out_dmic_free:

	skl_dmic_device_unregister(skl);

out_free:

	skl->init_failed = 1;

	skl_free(ebus);

	return err;

}

static void skl_remove(struct pci_dev *pci)

{

	struct hdac_ext_bus *ebus = pci_get_drvdata(pci);

	struct skl *skl = ebus_to_skl(ebus);

	if (pci_dev_run_wake(pci))

		pm_runtime_get_noresume(&pci->dev);

	pci_dev_put(pci);

	skl_platform_unregister(&pci->dev);

	skl_dmic_device_unregister(skl);

	skl_free(ebus);

	dev_set_drvdata(&pci->dev, NULL);

}

/* PCI IDs */

static const struct pci_device_id skl_ids[] = {

	/* Sunrise Point-LP */

	{ PCI_DEVICE(0x8086, 0x9d70), 0},

	{ 0, }

};

MODULE_DEVICE_TABLE(pci, skl_ids);

/* pci_driver definition */

static struct pci_driver skl_driver = {

	.name = KBUILD_MODNAME,

	.id_table = skl_ids,

	.probe = skl_probe,

	.remove = skl_remove,

	.driver = {

		.pm = &skl_pm,

	},

};

module_pci_driver(skl_driver);

MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("Intel Skylake ASoC HDA driver");