Linux 3.11-rc3

[cris-mirror.git] / sound / pci / hda / hda_hwdep.c

/*
 * HWDEP Interface for HD-audio codec
 *
 * Copyright (c) 2007 Takashi Iwai <tiwai@suse.de>
 *
 *  This driver 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 of the License, or
 *  (at your option) any later version.
 *
 *  This driver 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; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/init.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/compat.h>
#include <linux/mutex.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/export.h>
#include <sound/core.h>
#include "hda_codec.h"
#include "hda_local.h"
#include <sound/hda_hwdep.h>
#include <sound/minors.h>

/* hint string pair */
struct hda_hint {
        const char *key;
        const char *val;        /* contained in the same alloc as key */
};

/*
 * write/read an out-of-bound verb
 */
static int verb_write_ioctl(struct hda_codec *codec,
                            struct hda_verb_ioctl __user *arg)
{
        u32 verb, res;

        if (get_user(verb, &arg->verb))
                return -EFAULT;
        res = snd_hda_codec_read(codec, verb >> 24, 0,
                                 (verb >> 8) & 0xffff, verb & 0xff);
        if (put_user(res, &arg->res))
                return -EFAULT;
        return 0;
}

static int get_wcap_ioctl(struct hda_codec *codec,
                          struct hda_verb_ioctl __user *arg)
{
        u32 verb, res;
        
        if (get_user(verb, &arg->verb))
                return -EFAULT;
        res = get_wcaps(codec, verb >> 24);
        if (put_user(res, &arg->res))
                return -EFAULT;
        return 0;
}


/*
 */
static int hda_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
                           unsigned int cmd, unsigned long arg)
{
        struct hda_codec *codec = hw->private_data;
        void __user *argp = (void __user *)arg;

        switch (cmd) {
        case HDA_IOCTL_PVERSION:
                return put_user(HDA_HWDEP_VERSION, (int __user *)argp);
        case HDA_IOCTL_VERB_WRITE:
                return verb_write_ioctl(codec, argp);
        case HDA_IOCTL_GET_WCAP:
                return get_wcap_ioctl(codec, argp);
        }
        return -ENOIOCTLCMD;
}

#ifdef CONFIG_COMPAT
static int hda_hwdep_ioctl_compat(struct snd_hwdep *hw, struct file *file,
                                  unsigned int cmd, unsigned long arg)
{
        return hda_hwdep_ioctl(hw, file, cmd, (unsigned long)compat_ptr(arg));
}
#endif

static int hda_hwdep_open(struct snd_hwdep *hw, struct file *file)
{
#ifndef CONFIG_SND_DEBUG_VERBOSE
        if (!capable(CAP_SYS_RAWIO))
                return -EACCES;
#endif
        return 0;
}

static void clear_hwdep_elements(struct hda_codec *codec)
{
        int i;

        /* clear init verbs */
        snd_array_free(&codec->init_verbs);
        /* clear hints */
        for (i = 0; i < codec->hints.used; i++) {
                struct hda_hint *hint = snd_array_elem(&codec->hints, i);
                kfree(hint->key); /* we don't need to free hint->val */
        }
        snd_array_free(&codec->hints);
        snd_array_free(&codec->user_pins);
}

static void hwdep_free(struct snd_hwdep *hwdep)
{
        clear_hwdep_elements(hwdep->private_data);
}

int snd_hda_create_hwdep(struct hda_codec *codec)
{
        char hwname[16];
        struct snd_hwdep *hwdep;
        int err;

        sprintf(hwname, "HDA Codec %d", codec->addr);
        err = snd_hwdep_new(codec->bus->card, hwname, codec->addr, &hwdep);
        if (err < 0)
                return err;
        codec->hwdep = hwdep;
        sprintf(hwdep->name, "HDA Codec %d", codec->addr);
        hwdep->iface = SNDRV_HWDEP_IFACE_HDA;
        hwdep->private_data = codec;
        hwdep->private_free = hwdep_free;
        hwdep->exclusive = 1;

        hwdep->ops.open = hda_hwdep_open;
        hwdep->ops.ioctl = hda_hwdep_ioctl;
#ifdef CONFIG_COMPAT
        hwdep->ops.ioctl_compat = hda_hwdep_ioctl_compat;
#endif

        mutex_init(&codec->user_mutex);
        snd_array_init(&codec->init_verbs, sizeof(struct hda_verb), 32);
        snd_array_init(&codec->hints, sizeof(struct hda_hint), 32);
        snd_array_init(&codec->user_pins, sizeof(struct hda_pincfg), 16);

        return 0;
}

#ifdef CONFIG_PM
static ssize_t power_on_acct_show(struct device *dev,
                                  struct device_attribute *attr,
                                  char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        snd_hda_update_power_acct(codec);
        return sprintf(buf, "%u\n", jiffies_to_msecs(codec->power_on_acct));
}

static ssize_t power_off_acct_show(struct device *dev,
                                   struct device_attribute *attr,
                                   char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        snd_hda_update_power_acct(codec);
        return sprintf(buf, "%u\n", jiffies_to_msecs(codec->power_off_acct));
}

static struct device_attribute power_attrs[] = {
        __ATTR_RO(power_on_acct),
        __ATTR_RO(power_off_acct),
};

int snd_hda_hwdep_add_power_sysfs(struct hda_codec *codec)
{
        struct snd_hwdep *hwdep = codec->hwdep;
        int i;

        for (i = 0; i < ARRAY_SIZE(power_attrs); i++)
                snd_add_device_sysfs_file(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card,
                                          hwdep->device, &power_attrs[i]);
        return 0;
}
#endif /* CONFIG_PM */

#ifdef CONFIG_SND_HDA_RECONFIG

/*
 * sysfs interface
 */

static int clear_codec(struct hda_codec *codec)
{
        int err;

        err = snd_hda_codec_reset(codec);
        if (err < 0) {
                snd_printk(KERN_ERR "The codec is being used, can't free.\n");
                return err;
        }
        clear_hwdep_elements(codec);
        return 0;
}

static int reconfig_codec(struct hda_codec *codec)
{
        int err;

        snd_hda_power_up(codec);
        snd_printk(KERN_INFO "hda-codec: reconfiguring\n");
        err = snd_hda_codec_reset(codec);
        if (err < 0) {
                snd_printk(KERN_ERR
                           "The codec is being used, can't reconfigure.\n");
                goto error;
        }
        err = snd_hda_codec_configure(codec);
        if (err < 0)
                goto error;
        /* rebuild PCMs */
        err = snd_hda_codec_build_pcms(codec);
        if (err < 0)
                goto error;
        /* rebuild mixers */
        err = snd_hda_codec_build_controls(codec);
        if (err < 0)
                goto error;
        err = snd_card_register(codec->bus->card);
 error:
        snd_hda_power_down(codec);
        return err;
}

/*
 * allocate a string at most len chars, and remove the trailing EOL
 */
static char *kstrndup_noeol(const char *src, size_t len)
{
        char *s = kstrndup(src, len, GFP_KERNEL);
        char *p;
        if (!s)
                return NULL;
        p = strchr(s, '\n');
        if (p)
                *p = 0;
        return s;
}

#define CODEC_INFO_SHOW(type)                                   \
static ssize_t type##_show(struct device *dev,                  \
                           struct device_attribute *attr,       \
                           char *buf)                           \
{                                                               \
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);         \
        struct hda_codec *codec = hwdep->private_data;          \
        return sprintf(buf, "0x%x\n", codec->type);             \
}

#define CODEC_INFO_STR_SHOW(type)                               \
static ssize_t type##_show(struct device *dev,                  \
                             struct device_attribute *attr,     \
                                        char *buf)              \
{                                                               \
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);         \
        struct hda_codec *codec = hwdep->private_data;          \
        return sprintf(buf, "%s\n",                             \
                       codec->type ? codec->type : "");         \
}

CODEC_INFO_SHOW(vendor_id);
CODEC_INFO_SHOW(subsystem_id);
CODEC_INFO_SHOW(revision_id);
CODEC_INFO_SHOW(afg);
CODEC_INFO_SHOW(mfg);
CODEC_INFO_STR_SHOW(vendor_name);
CODEC_INFO_STR_SHOW(chip_name);
CODEC_INFO_STR_SHOW(modelname);

#define CODEC_INFO_STORE(type)                                  \
static ssize_t type##_store(struct device *dev,                 \
                            struct device_attribute *attr,      \
                            const char *buf, size_t count)      \
{                                                               \
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);         \
        struct hda_codec *codec = hwdep->private_data;          \
        unsigned long val;                                      \
        int err = strict_strtoul(buf, 0, &val);                 \
        if (err < 0)                                            \
                return err;                                     \
        codec->type = val;                                      \
        return count;                                           \
}

#define CODEC_INFO_STR_STORE(type)                              \
static ssize_t type##_store(struct device *dev,                 \
                            struct device_attribute *attr,      \
                            const char *buf, size_t count)      \
{                                                               \
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);         \
        struct hda_codec *codec = hwdep->private_data;          \
        char *s = kstrndup_noeol(buf, 64);                      \
        if (!s)                                                 \
                return -ENOMEM;                                 \
        kfree(codec->type);                                     \
        codec->type = s;                                        \
        return count;                                           \
}

CODEC_INFO_STORE(vendor_id);
CODEC_INFO_STORE(subsystem_id);
CODEC_INFO_STORE(revision_id);
CODEC_INFO_STR_STORE(vendor_name);
CODEC_INFO_STR_STORE(chip_name);
CODEC_INFO_STR_STORE(modelname);

#define CODEC_ACTION_STORE(type)                                \
static ssize_t type##_store(struct device *dev,                 \
                            struct device_attribute *attr,      \
                            const char *buf, size_t count)      \
{                                                               \
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);         \
        struct hda_codec *codec = hwdep->private_data;          \
        int err = 0;                                            \
        if (*buf)                                               \
                err = type##_codec(codec);                      \
        return err < 0 ? err : count;                           \
}

CODEC_ACTION_STORE(reconfig);
CODEC_ACTION_STORE(clear);

static ssize_t init_verbs_show(struct device *dev,
                               struct device_attribute *attr,
                               char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        int i, len = 0;
        mutex_lock(&codec->user_mutex);
        for (i = 0; i < codec->init_verbs.used; i++) {
                struct hda_verb *v = snd_array_elem(&codec->init_verbs, i);
                len += snprintf(buf + len, PAGE_SIZE - len,
                                "0x%02x 0x%03x 0x%04x\n",
                                v->nid, v->verb, v->param);
        }
        mutex_unlock(&codec->user_mutex);
        return len;
}

static int parse_init_verbs(struct hda_codec *codec, const char *buf)
{
        struct hda_verb *v;
        int nid, verb, param;

        if (sscanf(buf, "%i %i %i", &nid, &verb, &param) != 3)
                return -EINVAL;
        if (!nid || !verb)
                return -EINVAL;
        mutex_lock(&codec->user_mutex);
        v = snd_array_new(&codec->init_verbs);
        if (!v) {
                mutex_unlock(&codec->user_mutex);
                return -ENOMEM;
        }
        v->nid = nid;
        v->verb = verb;
        v->param = param;
        mutex_unlock(&codec->user_mutex);
        return 0;
}

static ssize_t init_verbs_store(struct device *dev,
                                struct device_attribute *attr,
                                const char *buf, size_t count)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        int err = parse_init_verbs(codec, buf);
        if (err < 0)
                return err;
        return count;
}

static ssize_t hints_show(struct device *dev,
                          struct device_attribute *attr,
                          char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        int i, len = 0;
        mutex_lock(&codec->user_mutex);
        for (i = 0; i < codec->hints.used; i++) {
                struct hda_hint *hint = snd_array_elem(&codec->hints, i);
                len += snprintf(buf + len, PAGE_SIZE - len,
                                "%s = %s\n", hint->key, hint->val);
        }
        mutex_unlock(&codec->user_mutex);
        return len;
}

static struct hda_hint *get_hint(struct hda_codec *codec, const char *key)
{
        int i;

        for (i = 0; i < codec->hints.used; i++) {
                struct hda_hint *hint = snd_array_elem(&codec->hints, i);
                if (!strcmp(hint->key, key))
                        return hint;
        }
        return NULL;
}

static void remove_trail_spaces(char *str)
{
        char *p;
        if (!*str)
                return;
        p = str + strlen(str) - 1;
        for (; isspace(*p); p--) {
                *p = 0;
                if (p == str)
                        return;
        }
}

#define MAX_HINTS       1024

static int parse_hints(struct hda_codec *codec, const char *buf)
{
        char *key, *val;
        struct hda_hint *hint;
        int err = 0;

        buf = skip_spaces(buf);
        if (!*buf || *buf == '#' || *buf == '\n')
                return 0;
        if (*buf == '=')
                return -EINVAL;
        key = kstrndup_noeol(buf, 1024);
        if (!key)
                return -ENOMEM;
        /* extract key and val */
        val = strchr(key, '=');
        if (!val) {
                kfree(key);
                return -EINVAL;
        }
        *val++ = 0;
        val = skip_spaces(val);
        remove_trail_spaces(key);
        remove_trail_spaces(val);
        mutex_lock(&codec->user_mutex);
        hint = get_hint(codec, key);
        if (hint) {
                /* replace */
                kfree(hint->key);
                hint->key = key;
                hint->val = val;
                goto unlock;
        }
        /* allocate a new hint entry */
        if (codec->hints.used >= MAX_HINTS)
                hint = NULL;
        else
                hint = snd_array_new(&codec->hints);
        if (hint) {
                hint->key = key;
                hint->val = val;
        } else {
                err = -ENOMEM;
        }
 unlock:
        mutex_unlock(&codec->user_mutex);
        if (err)
                kfree(key);
        return err;
}

static ssize_t hints_store(struct device *dev,
                           struct device_attribute *attr,
                           const char *buf, size_t count)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        int err = parse_hints(codec, buf);
        if (err < 0)
                return err;
        return count;
}

static ssize_t pin_configs_show(struct hda_codec *codec,
                                struct snd_array *list,
                                char *buf)
{
        int i, len = 0;
        mutex_lock(&codec->user_mutex);
        for (i = 0; i < list->used; i++) {
                struct hda_pincfg *pin = snd_array_elem(list, i);
                len += sprintf(buf + len, "0x%02x 0x%08x\n",
                               pin->nid, pin->cfg);
        }
        mutex_unlock(&codec->user_mutex);
        return len;
}

static ssize_t init_pin_configs_show(struct device *dev,
                                     struct device_attribute *attr,
                                     char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        return pin_configs_show(codec, &codec->init_pins, buf);
}

static ssize_t user_pin_configs_show(struct device *dev,
                                     struct device_attribute *attr,
                                     char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        return pin_configs_show(codec, &codec->user_pins, buf);
}

static ssize_t driver_pin_configs_show(struct device *dev,
                                       struct device_attribute *attr,
                                       char *buf)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        return pin_configs_show(codec, &codec->driver_pins, buf);
}

#define MAX_PIN_CONFIGS         32

static int parse_user_pin_configs(struct hda_codec *codec, const char *buf)
{
        int nid, cfg, err;

        if (sscanf(buf, "%i %i", &nid, &cfg) != 2)
                return -EINVAL;
        if (!nid)
                return -EINVAL;
        mutex_lock(&codec->user_mutex);
        err = snd_hda_add_pincfg(codec, &codec->user_pins, nid, cfg);
        mutex_unlock(&codec->user_mutex);
        return err;
}

static ssize_t user_pin_configs_store(struct device *dev,
                                      struct device_attribute *attr,
                                      const char *buf, size_t count)
{
        struct snd_hwdep *hwdep = dev_get_drvdata(dev);
        struct hda_codec *codec = hwdep->private_data;
        int err = parse_user_pin_configs(codec, buf);
        if (err < 0)
                return err;
        return count;
}

#define CODEC_ATTR_RW(type) \
        __ATTR(type, 0644, type##_show, type##_store)
#define CODEC_ATTR_RO(type) \
        __ATTR_RO(type)
#define CODEC_ATTR_WO(type) \
        __ATTR(type, 0200, NULL, type##_store)

static struct device_attribute codec_attrs[] = {
        CODEC_ATTR_RW(vendor_id),
        CODEC_ATTR_RW(subsystem_id),
        CODEC_ATTR_RW(revision_id),
        CODEC_ATTR_RO(afg),
        CODEC_ATTR_RO(mfg),
        CODEC_ATTR_RW(vendor_name),
        CODEC_ATTR_RW(chip_name),
        CODEC_ATTR_RW(modelname),
        CODEC_ATTR_RW(init_verbs),
        CODEC_ATTR_RW(hints),
        CODEC_ATTR_RO(init_pin_configs),
        CODEC_ATTR_RW(user_pin_configs),
        CODEC_ATTR_RO(driver_pin_configs),
        CODEC_ATTR_WO(reconfig),
        CODEC_ATTR_WO(clear),
};

/*
 * create sysfs files on hwdep directory
 */
int snd_hda_hwdep_add_sysfs(struct hda_codec *codec)
{
        struct snd_hwdep *hwdep = codec->hwdep;
        int i;

        for (i = 0; i < ARRAY_SIZE(codec_attrs); i++)
                snd_add_device_sysfs_file(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card,
                                          hwdep->device, &codec_attrs[i]);
        return 0;
}

/*
 * Look for hint string
 */
const char *snd_hda_get_hint(struct hda_codec *codec, const char *key)
{
        struct hda_hint *hint = get_hint(codec, key);
        return hint ? hint->val : NULL;
}
EXPORT_SYMBOL_HDA(snd_hda_get_hint);

int snd_hda_get_bool_hint(struct hda_codec *codec, const char *key)
{
        const char *p;
        int ret;

        mutex_lock(&codec->user_mutex);
        p = snd_hda_get_hint(codec, key);
        if (!p || !*p)
                ret = -ENOENT;
        else {
                switch (toupper(*p)) {
                case 'T': /* true */
                case 'Y': /* yes */
                case '1':
                        ret = 1;
                        break;
                default:
                        ret = 0;
                        break;
                }
        }
        mutex_unlock(&codec->user_mutex);
        return ret;
}
EXPORT_SYMBOL_HDA(snd_hda_get_bool_hint);

int snd_hda_get_int_hint(struct hda_codec *codec, const char *key, int *valp)
{
        const char *p;
        unsigned long val;
        int ret;

        mutex_lock(&codec->user_mutex);
        p = snd_hda_get_hint(codec, key);
        if (!p)
                ret = -ENOENT;
        else if (strict_strtoul(p, 0, &val))
                ret = -EINVAL;
        else {
                *valp = val;
                ret = 0;
        }
        mutex_unlock(&codec->user_mutex);
        return ret;
}
EXPORT_SYMBOL_HDA(snd_hda_get_int_hint);
#endif /* CONFIG_SND_HDA_RECONFIG */

#ifdef CONFIG_SND_HDA_PATCH_LOADER

/* parser mode */
enum {
        LINE_MODE_NONE,
        LINE_MODE_CODEC,
        LINE_MODE_MODEL,
        LINE_MODE_PINCFG,
        LINE_MODE_VERB,
        LINE_MODE_HINT,
        LINE_MODE_VENDOR_ID,
        LINE_MODE_SUBSYSTEM_ID,
        LINE_MODE_REVISION_ID,
        LINE_MODE_CHIP_NAME,
        NUM_LINE_MODES,
};

static inline int strmatch(const char *a, const char *b)
{
        return strnicmp(a, b, strlen(b)) == 0;
}

/* parse the contents after the line "[codec]"
 * accept only the line with three numbers, and assign the current codec
 */
static void parse_codec_mode(char *buf, struct hda_bus *bus,
                             struct hda_codec **codecp)
{
        int vendorid, subid, caddr;
        struct hda_codec *codec;

        *codecp = NULL;
        if (sscanf(buf, "%i %i %i", &vendorid, &subid, &caddr) == 3) {
                list_for_each_entry(codec, &bus->codec_list, list) {
                        if ((vendorid <= 0 || codec->vendor_id == vendorid) &&
                            (subid <= 0 || codec->subsystem_id == subid) &&
                            codec->addr == caddr) {
                                *codecp = codec;
                                break;
                        }
                }
        }
}

/* parse the contents after the other command tags, [pincfg], [verb],
 * [vendor_id], [subsystem_id], [revision_id], [chip_name], [hint] and [model]
 * just pass to the sysfs helper (only when any codec was specified)
 */
static void parse_pincfg_mode(char *buf, struct hda_bus *bus,
                              struct hda_codec **codecp)
{
        parse_user_pin_configs(*codecp, buf);
}

static void parse_verb_mode(char *buf, struct hda_bus *bus,
                            struct hda_codec **codecp)
{
        parse_init_verbs(*codecp, buf);
}

static void parse_hint_mode(char *buf, struct hda_bus *bus,
                            struct hda_codec **codecp)
{
        parse_hints(*codecp, buf);
}

static void parse_model_mode(char *buf, struct hda_bus *bus,
                             struct hda_codec **codecp)
{
        kfree((*codecp)->modelname);
        (*codecp)->modelname = kstrdup(buf, GFP_KERNEL);
}

static void parse_chip_name_mode(char *buf, struct hda_bus *bus,
                                 struct hda_codec **codecp)
{
        kfree((*codecp)->chip_name);
        (*codecp)->chip_name = kstrdup(buf, GFP_KERNEL);
}

#define DEFINE_PARSE_ID_MODE(name) \
static void parse_##name##_mode(char *buf, struct hda_bus *bus, \
                                 struct hda_codec **codecp) \
{ \
        unsigned long val; \
        if (!strict_strtoul(buf, 0, &val)) \
                (*codecp)->name = val; \
}

DEFINE_PARSE_ID_MODE(vendor_id);
DEFINE_PARSE_ID_MODE(subsystem_id);
DEFINE_PARSE_ID_MODE(revision_id);


struct hda_patch_item {
        const char *tag;
        void (*parser)(char *buf, struct hda_bus *bus, struct hda_codec **retc);
        int need_codec;
};

static struct hda_patch_item patch_items[NUM_LINE_MODES] = {
        [LINE_MODE_CODEC] = { "[codec]", parse_codec_mode, 0 },
        [LINE_MODE_MODEL] = { "[model]", parse_model_mode, 1 },
        [LINE_MODE_VERB] = { "[verb]", parse_verb_mode, 1 },
        [LINE_MODE_PINCFG] = { "[pincfg]", parse_pincfg_mode, 1 },
        [LINE_MODE_HINT] = { "[hint]", parse_hint_mode, 1 },
        [LINE_MODE_VENDOR_ID] = { "[vendor_id]", parse_vendor_id_mode, 1 },
        [LINE_MODE_SUBSYSTEM_ID] = { "[subsystem_id]", parse_subsystem_id_mode, 1 },
        [LINE_MODE_REVISION_ID] = { "[revision_id]", parse_revision_id_mode, 1 },
        [LINE_MODE_CHIP_NAME] = { "[chip_name]", parse_chip_name_mode, 1 },
};

/* check the line starting with '[' -- change the parser mode accodingly */
static int parse_line_mode(char *buf, struct hda_bus *bus)
{
        int i;
        for (i = 0; i < ARRAY_SIZE(patch_items); i++) {
                if (!patch_items[i].tag)
                        continue;
                if (strmatch(buf, patch_items[i].tag))
                        return i;
        }
        return LINE_MODE_NONE;
}

/* copy one line from the buffer in fw, and update the fields in fw
 * return zero if it reaches to the end of the buffer, or non-zero
 * if successfully copied a line
 *
 * the spaces at the beginning and the end of the line are stripped
 */
static int get_line_from_fw(char *buf, int size, size_t *fw_size_p,
                            const void **fw_data_p)
{
        int len;
        size_t fw_size = *fw_size_p;
        const char *p = *fw_data_p;

        while (isspace(*p) && fw_size) {
                p++;
                fw_size--;
        }
        if (!fw_size)
                return 0;

        for (len = 0; len < fw_size; len++) {
                if (!*p)
                        break;
                if (*p == '\n') {
                        p++;
                        len++;
                        break;
                }
                if (len < size)
                        *buf++ = *p++;
        }
        *buf = 0;
        *fw_size_p = fw_size - len;
        *fw_data_p = p;
        remove_trail_spaces(buf);
        return 1;
}

/*
 * load a "patch" firmware file and parse it
 */
int snd_hda_load_patch(struct hda_bus *bus, size_t fw_size, const void *fw_buf)
{
        char buf[128];
        struct hda_codec *codec;
        int line_mode;

        line_mode = LINE_MODE_NONE;
        codec = NULL;
        while (get_line_from_fw(buf, sizeof(buf) - 1, &fw_size, &fw_buf)) {
                if (!*buf || *buf == '#' || *buf == '\n')
                        continue;
                if (*buf == '[')
                        line_mode = parse_line_mode(buf, bus);
                else if (patch_items[line_mode].parser &&
                         (codec || !patch_items[line_mode].need_codec))
                        patch_items[line_mode].parser(buf, bus, &codec);
        }
        return 0;
}
EXPORT_SYMBOL_HDA(snd_hda_load_patch);
#endif /* CONFIG_SND_HDA_PATCH_LOADER */