sound/hda/ext/hdac_ext_controller.c - kernel/bruno - Git at Google

 /*
  *  hdac-ext-controller.c - HD-audio extended controller functions.
  *
  *  Copyright (C) 2014-2015 Intel Corp
  *  Author: Jeeja KP <jeeja.kp@intel.com>
  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  *
  *  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/delay.h>
 #include <linux/slab.h>
 #include <sound/hda_register.h>
 #include <sound/hdaudio_ext.h>

 /*
  * maximum HDAC capablities we should parse to avoid endless looping:
  * currently we have 4 extended caps, so this is future proof for now.
  * extend when this limit is seen meeting in real HW
  */
 #define HDAC_MAX_CAPS 10

 /**
  * snd_hdac_ext_bus_parse_capabilities - parse capablity structure
  * @ebus: the pointer to extended bus object
  *
  * Returns 0 if successful, or a negative error code.
  */
 int snd_hdac_ext_bus_parse_capabilities(struct hdac_ext_bus *ebus)
 {
 	unsigned int cur_cap;
 	unsigned int offset;
 	struct hdac_bus *bus = &ebus->bus;
 	unsigned int counter = 0;

 	offset = snd_hdac_chip_readl(bus, LLCH);

 	/* Lets walk the linked capabilities list */
 	do {
 		cur_cap = _snd_hdac_chip_read(l, bus, offset);

 		dev_dbg(bus->dev, "Capability version: 0x%x\n",
 				((cur_cap & AZX_CAP_HDR_VER_MASK) >> AZX_CAP_HDR_VER_OFF));

 		dev_dbg(bus->dev, "HDA capability ID: 0x%x\n",
 				(cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF);

 		switch ((cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF) {
 		case AZX_ML_CAP_ID:
 			dev_dbg(bus->dev, "Found ML capability\n");
 			ebus->mlcap = bus->remap_addr + offset;
 			break;

 		case AZX_GTS_CAP_ID:
 			dev_dbg(bus->dev, "Found GTS capability offset=%x\n", offset);
 			ebus->gtscap = bus->remap_addr + offset;
 			break;

 		case AZX_PP_CAP_ID:
 			/* PP capability found, the Audio DSP is present */
 			dev_dbg(bus->dev, "Found PP capability offset=%x\n", offset);
 			ebus->ppcap = bus->remap_addr + offset;
 			break;

 		case AZX_SPB_CAP_ID:
 			/* SPIB capability found, handler function */
 			dev_dbg(bus->dev, "Found SPB capability\n");
 			ebus->spbcap = bus->remap_addr + offset;
 			break;

 		default:
 			dev_dbg(bus->dev, "Unknown capability %d\n", cur_cap);
 			break;
 		}

 		counter++;

 		if (counter > HDAC_MAX_CAPS) {
 			dev_err(bus->dev, "We exceeded HDAC Ext capablities!!!\n");
 			break;
 		}

 		/* read the offset of next capabiity */
 		offset = cur_cap & AZX_CAP_HDR_NXT_PTR_MASK;

 	} while (offset);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_parse_capabilities);

 /*
  * processing pipe helpers - these helpers are useful for dealing with HDA
  * new capability of processing pipelines
  */

 /**
  * snd_hdac_ext_bus_ppcap_enable - enable/disable processing pipe capability
  * @ebus: HD-audio extended core bus
  * @enable: flag to turn on/off the capability
  */
 void snd_hdac_ext_bus_ppcap_enable(struct hdac_ext_bus *ebus, bool enable)
 {
 	struct hdac_bus *bus = &ebus->bus;

 	if (!ebus->ppcap) {
 		dev_err(bus->dev, "Address of PP capability is NULL");
 		return;
 	}

 	if (enable)
 		snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0, AZX_PPCTL_GPROCEN);
 	else
 		snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, AZX_PPCTL_GPROCEN, 0);
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_ppcap_enable);

 /**
  * snd_hdac_ext_bus_ppcap_int_enable - ppcap interrupt enable/disable
  * @ebus: HD-audio extended core bus
  * @enable: flag to enable/disable interrupt
  */
 void snd_hdac_ext_bus_ppcap_int_enable(struct hdac_ext_bus *ebus, bool enable)
 {
 	struct hdac_bus *bus = &ebus->bus;

 	if (!ebus->ppcap) {
 		dev_err(bus->dev, "Address of PP capability is NULL\n");
 		return;
 	}

 	if (enable)
 		snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0, AZX_PPCTL_PIE);
 	else
 		snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, AZX_PPCTL_PIE, 0);
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_ppcap_int_enable);

 /*
  * Multilink helpers - these helpers are useful for dealing with HDA
  * new multilink capability
  */

 /**
  * snd_hdac_ext_bus_get_ml_capabilities - get multilink capability
  * @ebus: HD-audio extended core bus
  *
  * This will parse all links and read the mlink capabilities and add them
  * in hlink_list of extended hdac bus
  * Note: this will be freed on bus exit by driver
  */
 int snd_hdac_ext_bus_get_ml_capabilities(struct hdac_ext_bus *ebus)
 {
 	int idx;
 	u32 link_count;
 	struct hdac_ext_link *hlink;
 	struct hdac_bus *bus = &ebus->bus;

 	link_count = readl(ebus->mlcap + AZX_REG_ML_MLCD) + 1;

 	dev_dbg(bus->dev, "In %s Link count: %d\n", __func__, link_count);

 	for (idx = 0; idx < link_count; idx++) {
 		hlink  = kzalloc(sizeof(*hlink), GFP_KERNEL);
 		if (!hlink)
 			return -ENOMEM;
 		hlink->index = idx;
 		hlink->bus = bus;
 		hlink->ml_addr = ebus->mlcap + AZX_ML_BASE +
 					(AZX_ML_INTERVAL * idx);
 		hlink->lcaps  = readl(hlink->ml_addr + AZX_REG_ML_LCAP);
 		hlink->lsdiid = readw(hlink->ml_addr + AZX_REG_ML_LSDIID);

 		list_add_tail(&hlink->list, &ebus->hlink_list);
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_ml_capabilities);

 /**
  * snd_hdac_link_free_all- free hdac extended link objects
  *
  * @ebus: HD-audio ext core bus
  */

 void snd_hdac_link_free_all(struct hdac_ext_bus *ebus)
 {
 	struct hdac_ext_link *l;

 	while (!list_empty(&ebus->hlink_list)) {
 		l = list_first_entry(&ebus->hlink_list, struct hdac_ext_link, list);
 		list_del(&l->list);
 		kfree(l);
 	}
 }
 EXPORT_SYMBOL_GPL(snd_hdac_link_free_all);

 /**
  * snd_hdac_ext_bus_get_link_index - get link based on codec name
  * @ebus: HD-audio extended core bus
  * @codec_name: codec name
  */
 struct hdac_ext_link *snd_hdac_ext_bus_get_link(struct hdac_ext_bus *ebus,
 						 const char *codec_name)
 {
 	int i;
 	struct hdac_ext_link *hlink = NULL;
 	int bus_idx, addr;

 	if (sscanf(codec_name, "ehdaudio%dD%d", &bus_idx, &addr) != 2)
 		return NULL;
 	if (ebus->idx != bus_idx)
 		return NULL;

 	list_for_each_entry(hlink, &ebus->hlink_list, list) {
 		for (i = 0; i < HDA_MAX_CODECS; i++) {
 			if (hlink->lsdiid & (0x1 << addr))
 				return hlink;
 		}
 	}

 	return NULL;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_link);

 static int check_hdac_link_power_active(struct hdac_ext_link *link, bool enable)
 {
 	int timeout;
 	u32 val;
 	int mask = (1 << AZX_MLCTL_CPA);

 	udelay(3);
 	timeout = 50;

 	do {
 		val = readl(link->ml_addr + AZX_REG_ML_LCTL);
 		if (enable) {
 			if (((val & mask) >> AZX_MLCTL_CPA))
 				return 0;
 		} else {
 			if (!((val & mask) >> AZX_MLCTL_CPA))
 				return 0;
 		}
 		udelay(3);
 	} while (--timeout);

 	return -EIO;
 }

 /**
  * snd_hdac_ext_bus_link_power_up -power up hda link
  * @link: HD-audio extended link
  */
 int snd_hdac_ext_bus_link_power_up(struct hdac_ext_link *link)
 {
 	snd_hdac_updatel(link->ml_addr, AZX_REG_ML_LCTL, 0, AZX_MLCTL_SPA);

 	return check_hdac_link_power_active(link, true);
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_up);

 /**
  * snd_hdac_ext_bus_link_power_down -power down hda link
  * @link: HD-audio extended link
  */
 int snd_hdac_ext_bus_link_power_down(struct hdac_ext_link *link)
 {
 	snd_hdac_updatel(link->ml_addr, AZX_REG_ML_LCTL, AZX_MLCTL_SPA, 0);

 	return check_hdac_link_power_active(link, false);
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_down);

 /**
  * snd_hdac_ext_bus_link_power_down_all -power down all hda link
  * @ebus: HD-audio extended bus
  */
 int snd_hdac_ext_bus_link_power_down_all(struct hdac_ext_bus *ebus)
 {
 	struct hdac_ext_link *hlink = NULL;
 	int ret;

 	list_for_each_entry(hlink, &ebus->hlink_list, list) {
 		snd_hdac_updatel(hlink->ml_addr, AZX_REG_ML_LCTL, AZX_MLCTL_SPA, 0);
 		ret = check_hdac_link_power_active(hlink, false);
 		if (ret < 0)
 			return ret;
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_down_all);
	/*
	* hdac-ext-controller.c - HD-audio extended controller functions.
	*
	* Copyright (C) 2014-2015 Intel Corp
	* Author: Jeeja KP <jeeja.kp@intel.com>
	* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	*
	* 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/delay.h>
	#include <linux/slab.h>
	#include <sound/hda_register.h>
	#include <sound/hdaudio_ext.h>

	/*
	* maximum HDAC capablities we should parse to avoid endless looping:
	* currently we have 4 extended caps, so this is future proof for now.
	* extend when this limit is seen meeting in real HW
	*/
	#define HDAC_MAX_CAPS 10

	/**
	* snd_hdac_ext_bus_parse_capabilities - parse capablity structure
	* @ebus: the pointer to extended bus object
	*
	* Returns 0 if successful, or a negative error code.
	*/
	int snd_hdac_ext_bus_parse_capabilities(struct hdac_ext_bus *ebus)
	{
	unsigned int cur_cap;
	unsigned int offset;
	struct hdac_bus *bus = &ebus->bus;
	unsigned int counter = 0;

	offset = snd_hdac_chip_readl(bus, LLCH);

	/* Lets walk the linked capabilities list */
	do {
	cur_cap = _snd_hdac_chip_read(l, bus, offset);

	dev_dbg(bus->dev, "Capability version: 0x%x\n",
	((cur_cap & AZX_CAP_HDR_VER_MASK) >> AZX_CAP_HDR_VER_OFF));

	dev_dbg(bus->dev, "HDA capability ID: 0x%x\n",
	(cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF);

	switch ((cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF) {
	case AZX_ML_CAP_ID:
	dev_dbg(bus->dev, "Found ML capability\n");
	ebus->mlcap = bus->remap_addr + offset;
	break;

	case AZX_GTS_CAP_ID:
	dev_dbg(bus->dev, "Found GTS capability offset=%x\n", offset);
	ebus->gtscap = bus->remap_addr + offset;
	break;

	case AZX_PP_CAP_ID:
	/* PP capability found, the Audio DSP is present */
	dev_dbg(bus->dev, "Found PP capability offset=%x\n", offset);
	ebus->ppcap = bus->remap_addr + offset;
	break;

	case AZX_SPB_CAP_ID:
	/* SPIB capability found, handler function */
	dev_dbg(bus->dev, "Found SPB capability\n");
	ebus->spbcap = bus->remap_addr + offset;
	break;

	default:
	dev_dbg(bus->dev, "Unknown capability %d\n", cur_cap);
	break;
	}

	counter++;

	if (counter > HDAC_MAX_CAPS) {
	dev_err(bus->dev, "We exceeded HDAC Ext capablities!!!\n");
	break;
	}

	/* read the offset of next capabiity */
	offset = cur_cap & AZX_CAP_HDR_NXT_PTR_MASK;

	} while (offset);

	return 0;
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_parse_capabilities);

	/*
	* processing pipe helpers - these helpers are useful for dealing with HDA
	* new capability of processing pipelines
	*/

	/**
	* snd_hdac_ext_bus_ppcap_enable - enable/disable processing pipe capability
	* @ebus: HD-audio extended core bus
	* @enable: flag to turn on/off the capability
	*/
	void snd_hdac_ext_bus_ppcap_enable(struct hdac_ext_bus *ebus, bool enable)
	{
	struct hdac_bus *bus = &ebus->bus;

	if (!ebus->ppcap) {
	dev_err(bus->dev, "Address of PP capability is NULL");
	return;
	}

	if (enable)
	snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0, AZX_PPCTL_GPROCEN);
	else
	snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, AZX_PPCTL_GPROCEN, 0);
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_ppcap_enable);

	/**
	* snd_hdac_ext_bus_ppcap_int_enable - ppcap interrupt enable/disable
	* @ebus: HD-audio extended core bus
	* @enable: flag to enable/disable interrupt
	*/
	void snd_hdac_ext_bus_ppcap_int_enable(struct hdac_ext_bus *ebus, bool enable)
	{
	struct hdac_bus *bus = &ebus->bus;

	if (!ebus->ppcap) {
	dev_err(bus->dev, "Address of PP capability is NULL\n");
	return;
	}

	if (enable)
	snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0, AZX_PPCTL_PIE);
	else
	snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, AZX_PPCTL_PIE, 0);
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_ppcap_int_enable);

	/*
	* Multilink helpers - these helpers are useful for dealing with HDA
	* new multilink capability
	*/

	/**
	* snd_hdac_ext_bus_get_ml_capabilities - get multilink capability
	* @ebus: HD-audio extended core bus
	*
	* This will parse all links and read the mlink capabilities and add them
	* in hlink_list of extended hdac bus
	* Note: this will be freed on bus exit by driver
	*/
	int snd_hdac_ext_bus_get_ml_capabilities(struct hdac_ext_bus *ebus)
	{
	int idx;
	u32 link_count;
	struct hdac_ext_link *hlink;
	struct hdac_bus *bus = &ebus->bus;

	link_count = readl(ebus->mlcap + AZX_REG_ML_MLCD) + 1;

	dev_dbg(bus->dev, "In %s Link count: %d\n", __func__, link_count);

	for (idx = 0; idx < link_count; idx++) {
	hlink = kzalloc(sizeof(*hlink), GFP_KERNEL);
	if (!hlink)
	return -ENOMEM;
	hlink->index = idx;
	hlink->bus = bus;
	hlink->ml_addr = ebus->mlcap + AZX_ML_BASE +
	(AZX_ML_INTERVAL * idx);
	hlink->lcaps = readl(hlink->ml_addr + AZX_REG_ML_LCAP);
	hlink->lsdiid = readw(hlink->ml_addr + AZX_REG_ML_LSDIID);

	list_add_tail(&hlink->list, &ebus->hlink_list);
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_ml_capabilities);

	/**
	* snd_hdac_link_free_all- free hdac extended link objects
	*
	* @ebus: HD-audio ext core bus
	*/

	void snd_hdac_link_free_all(struct hdac_ext_bus *ebus)
	{
	struct hdac_ext_link *l;

	while (!list_empty(&ebus->hlink_list)) {
	l = list_first_entry(&ebus->hlink_list, struct hdac_ext_link, list);
	list_del(&l->list);
	kfree(l);
	}
	}
	EXPORT_SYMBOL_GPL(snd_hdac_link_free_all);

	/**
	* snd_hdac_ext_bus_get_link_index - get link based on codec name
	* @ebus: HD-audio extended core bus
	* @codec_name: codec name
	*/
	struct hdac_ext_link snd_hdac_ext_bus_get_link(struct hdac_ext_bus ebus,
	const char *codec_name)
	{
	int i;
	struct hdac_ext_link *hlink = NULL;
	int bus_idx, addr;

	if (sscanf(codec_name, "ehdaudio%dD%d", &bus_idx, &addr) != 2)
	return NULL;
	if (ebus->idx != bus_idx)
	return NULL;

	list_for_each_entry(hlink, &ebus->hlink_list, list) {
	for (i = 0; i < HDA_MAX_CODECS; i++) {
	if (hlink->lsdiid & (0x1 << addr))
	return hlink;
	}
	}

	return NULL;
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_link);

	static int check_hdac_link_power_active(struct hdac_ext_link *link, bool enable)
	{
	int timeout;
	u32 val;
	int mask = (1 << AZX_MLCTL_CPA);

	udelay(3);
	timeout = 50;

	do {
	val = readl(link->ml_addr + AZX_REG_ML_LCTL);
	if (enable) {
	if (((val & mask) >> AZX_MLCTL_CPA))
	return 0;
	} else {
	if (!((val & mask) >> AZX_MLCTL_CPA))
	return 0;
	}
	udelay(3);
	} while (--timeout);

	return -EIO;
	}

	/**
	* snd_hdac_ext_bus_link_power_up -power up hda link
	* @link: HD-audio extended link
	*/
	int snd_hdac_ext_bus_link_power_up(struct hdac_ext_link *link)
	{
	snd_hdac_updatel(link->ml_addr, AZX_REG_ML_LCTL, 0, AZX_MLCTL_SPA);

	return check_hdac_link_power_active(link, true);
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_up);

	/**
	* snd_hdac_ext_bus_link_power_down -power down hda link
	* @link: HD-audio extended link
	*/
	int snd_hdac_ext_bus_link_power_down(struct hdac_ext_link *link)
	{
	snd_hdac_updatel(link->ml_addr, AZX_REG_ML_LCTL, AZX_MLCTL_SPA, 0);

	return check_hdac_link_power_active(link, false);
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_down);

	/**
	* snd_hdac_ext_bus_link_power_down_all -power down all hda link
	* @ebus: HD-audio extended bus
	*/
	int snd_hdac_ext_bus_link_power_down_all(struct hdac_ext_bus *ebus)
	{
	struct hdac_ext_link *hlink = NULL;
	int ret;

	list_for_each_entry(hlink, &ebus->hlink_list, list) {
	snd_hdac_updatel(hlink->ml_addr, AZX_REG_ML_LCTL, AZX_MLCTL_SPA, 0);
	ret = check_hdac_link_power_active(hlink, false);
	if (ret < 0)
	return ret;
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_down_all);