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root/sound/soc/soc-dapm.c

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DEFINITIONS

This source file includes following definitions.
  1. pop_wait
  2. pop_dbg
  3. dapm_cnew_widget
  4. dapm_set_path_status
  5. dapm_connect_mux
  6. dapm_connect_mixer
  7. dapm_update_bits
  8. dapm_set_pga
  9. dapm_new_mixer
  10. dapm_new_mux
  11. dapm_new_pga
  12. dapm_clear_walk
  13. is_connected_output_ep
  14. is_connected_input_ep
  15. dapm_reg_event
  16. dapm_power_widgets
  17. dbg_dump_dapm
  18. dapm_mux_update_power
  19. dapm_mixer_update_power
  20. dapm_widget_show
  21. snd_soc_dapm_sys_add
  22. snd_soc_dapm_sys_remove
  23. dapm_free_widgets
  24. snd_soc_dapm_set_pin
  25. snd_soc_dapm_sync
  26. snd_soc_dapm_add_route
  27. snd_soc_dapm_connect_input
  28. snd_soc_dapm_add_routes
  29. snd_soc_dapm_new_widgets
  30. snd_soc_dapm_get_volsw
  31. snd_soc_dapm_put_volsw
  32. snd_soc_dapm_get_enum_double
  33. snd_soc_dapm_put_enum_double
  34. snd_soc_dapm_new_control
  35. snd_soc_dapm_new_controls
  36. snd_soc_dapm_stream_event
  37. snd_soc_dapm_set_bias_level
  38. snd_soc_dapm_enable_pin
  39. snd_soc_dapm_disable_pin
  40. snd_soc_dapm_nc_pin
  41. snd_soc_dapm_get_pin_status
  42. snd_soc_dapm_free

/*
 * soc-dapm.c  --  ALSA SoC Dynamic Audio Power Management
 *
 * Copyright 2005 Wolfson Microelectronics PLC.
 * Author: Liam Girdwood <lrg@slimlogic.co.uk>
 *
 *  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;  either version 2 of the  License, or (at your
 *  option) any later version.
 *
 *  Features:
 *    o Changes power status of internal codec blocks depending on the
 *      dynamic configuration of codec internal audio paths and active
 *      DAC's/ADC's.
 *    o Platform power domain - can support external components i.e. amps and
 *      mic/meadphone insertion events.
 *    o Automatic Mic Bias support
 *    o Jack insertion power event initiation - e.g. hp insertion will enable
 *      sinks, dacs, etc
 *    o Delayed powerdown of audio susbsystem to reduce pops between a quick
 *      device reopen.
 *
 *  Todo:
 *    o DAPM power change sequencing - allow for configurable per
 *      codec sequences.
 *    o Support for analogue bias optimisation.
 *    o Support for reduced codec oversampling rates.
 *    o Support for reduced codec bias currents.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/bitops.h>
#include <linux/platform_device.h>
#include <linux/jiffies.h>
#include <linux/debugfs.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc-dapm.h>
#include <sound/initval.h>

/* debug */
#ifdef DEBUG
#define dump_dapm(codec, action) dbg_dump_dapm(codec, action)
#else
#define dump_dapm(codec, action)
#endif

/* dapm power sequences - make this per codec in the future */
static int dapm_up_seq[] = {
        snd_soc_dapm_pre, snd_soc_dapm_micbias, snd_soc_dapm_mic,
        snd_soc_dapm_mux, snd_soc_dapm_dac, snd_soc_dapm_mixer, snd_soc_dapm_pga,
        snd_soc_dapm_adc, snd_soc_dapm_hp, snd_soc_dapm_spk, snd_soc_dapm_post
};
static int dapm_down_seq[] = {
        snd_soc_dapm_pre, snd_soc_dapm_adc, snd_soc_dapm_hp, snd_soc_dapm_spk,
        snd_soc_dapm_pga, snd_soc_dapm_mixer, snd_soc_dapm_dac, snd_soc_dapm_mic,
        snd_soc_dapm_micbias, snd_soc_dapm_mux, snd_soc_dapm_post
};

static int dapm_status = 1;
module_param(dapm_status, int, 0);
MODULE_PARM_DESC(dapm_status, "enable DPM sysfs entries");

static struct dentry *asoc_debugfs;

static u32 pop_time;

static void pop_wait(void)
{
        if (pop_time)
                schedule_timeout_uninterruptible(msecs_to_jiffies(pop_time));
}

static void pop_dbg(const char *fmt, ...)
{
        va_list args;

        va_start(args, fmt);

        if (pop_time) {
                vprintk(fmt, args);
                pop_wait();
        }

        va_end(args);
}

/* create a new dapm widget */
static inline struct snd_soc_dapm_widget *dapm_cnew_widget(
        const struct snd_soc_dapm_widget *_widget)
{
        return kmemdup(_widget, sizeof(*_widget), GFP_KERNEL);
}

/* set up initial codec paths */
static void dapm_set_path_status(struct snd_soc_dapm_widget *w,
        struct snd_soc_dapm_path *p, int i)
{
        switch (w->id) {
        case snd_soc_dapm_switch:
        case snd_soc_dapm_mixer: {
                int val;
                struct soc_mixer_control *mc = (struct soc_mixer_control *)
                        w->kcontrols[i].private_value;
                unsigned int reg = mc->reg;
                unsigned int shift = mc->shift;
                int max = mc->max;
                unsigned int mask = (1 << fls(max)) - 1;
                unsigned int invert = mc->invert;

                val = snd_soc_read(w->codec, reg);
                val = (val >> shift) & mask;

                if ((invert && !val) || (!invert && val))
                        p->connect = 1;
                else
                        p->connect = 0;
        }
        break;
        case snd_soc_dapm_mux: {
                struct soc_enum *e = (struct soc_enum *)w->kcontrols[i].private_value;
                int val, item, bitmask;

                for (bitmask = 1; bitmask < e->max; bitmask <<= 1)
                ;
                val = snd_soc_read(w->codec, e->reg);
                item = (val >> e->shift_l) & (bitmask - 1);

                p->connect = 0;
                for (i = 0; i < e->max; i++) {
                        if (!(strcmp(p->name, e->texts[i])) && item == i)
                                p->connect = 1;
                }
        }
        break;
        /* does not effect routing - always connected */
        case snd_soc_dapm_pga:
        case snd_soc_dapm_output:
        case snd_soc_dapm_adc:
        case snd_soc_dapm_input:
        case snd_soc_dapm_dac:
        case snd_soc_dapm_micbias:
        case snd_soc_dapm_vmid:
                p->connect = 1;
        break;
        /* does effect routing - dynamically connected */
        case snd_soc_dapm_hp:
        case snd_soc_dapm_mic:
        case snd_soc_dapm_spk:
        case snd_soc_dapm_line:
        case snd_soc_dapm_pre:
        case snd_soc_dapm_post:
                p->connect = 0;
        break;
        }
}

/* connect mux widget to it's interconnecting audio paths */
static int dapm_connect_mux(struct snd_soc_codec *codec,
        struct snd_soc_dapm_widget *src, struct snd_soc_dapm_widget *dest,
        struct snd_soc_dapm_path *path, const char *control_name,
        const struct snd_kcontrol_new *kcontrol)
{
        struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
        int i;

        for (i = 0; i < e->max; i++) {
                if (!(strcmp(control_name, e->texts[i]))) {
                        list_add(&path->list, &codec->dapm_paths);
                        list_add(&path->list_sink, &dest->sources);
                        list_add(&path->list_source, &src->sinks);
                        path->name = (char*)e->texts[i];
                        dapm_set_path_status(dest, path, 0);
                        return 0;
                }
        }

        return -ENODEV;
}

/* connect mixer widget to it's interconnecting audio paths */
static int dapm_connect_mixer(struct snd_soc_codec *codec,
        struct snd_soc_dapm_widget *src, struct snd_soc_dapm_widget *dest,
        struct snd_soc_dapm_path *path, const char *control_name)
{
        int i;

        /* search for mixer kcontrol */
        for (i = 0; i < dest->num_kcontrols; i++) {
                if (!strcmp(control_name, dest->kcontrols[i].name)) {
                        list_add(&path->list, &codec->dapm_paths);
                        list_add(&path->list_sink, &dest->sources);
                        list_add(&path->list_source, &src->sinks);
                        path->name = dest->kcontrols[i].name;
                        dapm_set_path_status(dest, path, i);
                        return 0;
                }
        }
        return -ENODEV;
}

/* update dapm codec register bits */
static int dapm_update_bits(struct snd_soc_dapm_widget *widget)
{
        int change, power;
        unsigned short old, new;
        struct snd_soc_codec *codec = widget->codec;

        /* check for valid widgets */
        if (widget->reg < 0 || widget->id == snd_soc_dapm_input ||
                widget->id == snd_soc_dapm_output ||
                widget->id == snd_soc_dapm_hp ||
                widget->id == snd_soc_dapm_mic ||
                widget->id == snd_soc_dapm_line ||
                widget->id == snd_soc_dapm_spk)
                return 0;

        power = widget->power;
        if (widget->invert)
                power = (power ? 0:1);

        old = snd_soc_read(codec, widget->reg);
        new = (old & ~(0x1 << widget->shift)) | (power << widget->shift);

        change = old != new;
        if (change) {
                pop_dbg("pop test %s : %s in %d ms\n", widget->name,
                        widget->power ? "on" : "off", pop_time);
                snd_soc_write(codec, widget->reg, new);
                pop_wait();
        }
        pr_debug("reg %x old %x new %x change %d\n", widget->reg,
                 old, new, change);
        return change;
}

/* ramps the volume up or down to minimise pops before or after a
 * DAPM power event */
static int dapm_set_pga(struct snd_soc_dapm_widget *widget, int power)
{
        const struct snd_kcontrol_new *k = widget->kcontrols;

        if (widget->muted && !power)
                return 0;
        if (!widget->muted && power)
                return 0;

        if (widget->num_kcontrols && k) {
                struct soc_mixer_control *mc =
                        (struct soc_mixer_control *)k->private_value;
                unsigned int reg = mc->reg;
                unsigned int shift = mc->shift;
                int max = mc->max;
                unsigned int mask = (1 << fls(max)) - 1;
                unsigned int invert = mc->invert;

                if (power) {
                        int i;
                        /* power up has happended, increase volume to last level */
                        if (invert) {
                                for (i = max; i > widget->saved_value; i--)
                                        snd_soc_update_bits(widget->codec, reg, mask, i);
                        } else {
                                for (i = 0; i < widget->saved_value; i++)
                                        snd_soc_update_bits(widget->codec, reg, mask, i);
                        }
                        widget->muted = 0;
                } else {
                        /* power down is about to occur, decrease volume to mute */
                        int val = snd_soc_read(widget->codec, reg);
                        int i = widget->saved_value = (val >> shift) & mask;
                        if (invert) {
                                for (; i < mask; i++)
                                        snd_soc_update_bits(widget->codec, reg, mask, i);
                        } else {
                                for (; i > 0; i--)
                                        snd_soc_update_bits(widget->codec, reg, mask, i);
                        }
                        widget->muted = 1;
                }
        }
        return 0;
}

/* create new dapm mixer control */
static int dapm_new_mixer(struct snd_soc_codec *codec,
        struct snd_soc_dapm_widget *w)
{
        int i, ret = 0;
        char name[32];
        struct snd_soc_dapm_path *path;

        /* add kcontrol */
        for (i = 0; i < w->num_kcontrols; i++) {

                /* match name */
                list_for_each_entry(path, &w->sources, list_sink) {

                        /* mixer/mux paths name must match control name */
                        if (path->name != (char*)w->kcontrols[i].name)
                                continue;

                        /* add dapm control with long name */
                        snprintf(name, 32, "%s %s", w->name, w->kcontrols[i].name);
                        path->long_name = kstrdup (name, GFP_KERNEL);
                        if (path->long_name == NULL)
                                return -ENOMEM;

                        path->kcontrol = snd_soc_cnew(&w->kcontrols[i], w,
                                path->long_name);
                        ret = snd_ctl_add(codec->card, path->kcontrol);
                        if (ret < 0) {
                                printk(KERN_ERR "asoc: failed to add dapm kcontrol %s\n",
                                                path->long_name);
                                kfree(path->long_name);
                                path->long_name = NULL;
                                return ret;
                        }
                }
        }
        return ret;
}

/* create new dapm mux control */
static int dapm_new_mux(struct snd_soc_codec *codec,
        struct snd_soc_dapm_widget *w)
{
        struct snd_soc_dapm_path *path = NULL;
        struct snd_kcontrol *kcontrol;
        int ret = 0;

        if (!w->num_kcontrols) {
                printk(KERN_ERR "asoc: mux %s has no controls\n", w->name);
                return -EINVAL;
        }

        kcontrol = snd_soc_cnew(&w->kcontrols[0], w, w->name);
        ret = snd_ctl_add(codec->card, kcontrol);
        if (ret < 0)
                goto err;

        list_for_each_entry(path, &w->sources, list_sink)
                path->kcontrol = kcontrol;

        return ret;

err:
        printk(KERN_ERR "asoc: failed to add kcontrol %s\n", w->name);
        return ret;
}

/* create new dapm volume control */
static int dapm_new_pga(struct snd_soc_codec *codec,
        struct snd_soc_dapm_widget *w)
{
        struct snd_kcontrol *kcontrol;
        int ret = 0;

        if (!w->num_kcontrols)
                return -EINVAL;

        kcontrol = snd_soc_cnew(&w->kcontrols[0], w, w->name);
        ret = snd_ctl_add(codec->card, kcontrol);
        if (ret < 0) {
                printk(KERN_ERR "asoc: failed to add kcontrol %s\n", w->name);
                return ret;
        }

        return ret;
}

/* reset 'walked' bit for each dapm path */
static inline void dapm_clear_walk(struct snd_soc_codec *codec)
{
        struct snd_soc_dapm_path *p;

        list_for_each_entry(p, &codec->dapm_paths, list)
                p->walked = 0;
}

/*
 * Recursively check for a completed path to an active or physically connected
 * output widget. Returns number of complete paths.
 */
static int is_connected_output_ep(struct snd_soc_dapm_widget *widget)
{
        struct snd_soc_dapm_path *path;
        int con = 0;

        if (widget->id == snd_soc_dapm_adc && widget->active)
                return 1;

        if (widget->connected) {
                /* connected pin ? */
                if (widget->id == snd_soc_dapm_output && !widget->ext)
                        return 1;

                /* connected jack or spk ? */
                if (widget->id == snd_soc_dapm_hp || widget->id == snd_soc_dapm_spk ||
                        widget->id == snd_soc_dapm_line)
                        return 1;
        }

        list_for_each_entry(path, &widget->sinks, list_source) {
                if (path->walked)
                        continue;

                if (path->sink && path->connect) {
                        path->walked = 1;
                        con += is_connected_output_ep(path->sink);
                }
        }

        return con;
}

/*
 * Recursively check for a completed path to an active or physically connected
 * input widget. Returns number of complete paths.
 */
static int is_connected_input_ep(struct snd_soc_dapm_widget *widget)
{
        struct snd_soc_dapm_path *path;
        int con = 0;

        /* active stream ? */
        if (widget->id == snd_soc_dapm_dac && widget->active)
                return 1;

        if (widget->connected) {
                /* connected pin ? */
                if (widget->id == snd_soc_dapm_input && !widget->ext)
                        return 1;

                /* connected VMID/Bias for lower pops */
                if (widget->id == snd_soc_dapm_vmid)
                        return 1;

                /* connected jack ? */
                if (widget->id == snd_soc_dapm_mic || widget->id == snd_soc_dapm_line)
                        return 1;
        }

        list_for_each_entry(path, &widget->sources, list_sink) {
                if (path->walked)
                        continue;

                if (path->source && path->connect) {
                        path->walked = 1;
                        con += is_connected_input_ep(path->source);
                }
        }

        return con;
}

/*
 * Handler for generic register modifier widget.
 */
int dapm_reg_event(struct snd_soc_dapm_widget *w,
                   struct snd_kcontrol *kcontrol, int event)
{
        unsigned int val;

        if (SND_SOC_DAPM_EVENT_ON(event))
                val = w->on_val;
        else
                val = w->off_val;

        snd_soc_update_bits(w->codec, -(w->reg + 1),
                            w->mask << w->shift, val << w->shift);

        return 0;
}
EXPORT_SYMBOL_GPL(dapm_reg_event);

/*
 * Scan each dapm widget for complete audio path.
 * A complete path is a route that has valid endpoints i.e.:-
 *
 *  o DAC to output pin.
 *  o Input Pin to ADC.
 *  o Input pin to Output pin (bypass, sidetone)
 *  o DAC to ADC (loopback).
 */
static int dapm_power_widgets(struct snd_soc_codec *codec, int event)
{
        struct snd_soc_dapm_widget *w;
        int in, out, i, c = 1, *seq = NULL, ret = 0, power_change, power;

        /* do we have a sequenced stream event */
        if (event == SND_SOC_DAPM_STREAM_START) {
                c = ARRAY_SIZE(dapm_up_seq);
                seq = dapm_up_seq;
        } else if (event == SND_SOC_DAPM_STREAM_STOP) {
                c = ARRAY_SIZE(dapm_down_seq);
                seq = dapm_down_seq;
        }

        for(i = 0; i < c; i++) {
                list_for_each_entry(w, &codec->dapm_widgets, list) {

                        /* is widget in stream order */
                        if (seq && seq[i] && w->id != seq[i])
                                continue;

                        /* vmid - no action */
                        if (w->id == snd_soc_dapm_vmid)
                                continue;

                        /* active ADC */
                        if (w->id == snd_soc_dapm_adc && w->active) {
                                in = is_connected_input_ep(w);
                                dapm_clear_walk(w->codec);
                                w->power = (in != 0) ? 1 : 0;
                                dapm_update_bits(w);
                                continue;
                        }

                        /* active DAC */
                        if (w->id == snd_soc_dapm_dac && w->active) {
                                out = is_connected_output_ep(w);
                                dapm_clear_walk(w->codec);
                                w->power = (out != 0) ? 1 : 0;
                                dapm_update_bits(w);
                                continue;
                        }

                        /* pre and post event widgets */
                        if (w->id == snd_soc_dapm_pre) {
                                if (!w->event)
                                        continue;

                                if (event == SND_SOC_DAPM_STREAM_START) {
                                        ret = w->event(w,
                                                NULL, SND_SOC_DAPM_PRE_PMU);
                                        if (ret < 0)
                                                return ret;
                                } else if (event == SND_SOC_DAPM_STREAM_STOP) {
                                        ret = w->event(w,
                                                NULL, SND_SOC_DAPM_PRE_PMD);
                                        if (ret < 0)
                                                return ret;
                                }
                                continue;
                        }
                        if (w->id == snd_soc_dapm_post) {
                                if (!w->event)
                                        continue;

                                if (event == SND_SOC_DAPM_STREAM_START) {
                                        ret = w->event(w,
                                                NULL, SND_SOC_DAPM_POST_PMU);
                                        if (ret < 0)
                                                return ret;
                                } else if (event == SND_SOC_DAPM_STREAM_STOP) {
                                        ret = w->event(w,
                                                NULL, SND_SOC_DAPM_POST_PMD);
                                        if (ret < 0)
                                                return ret;
                                }
                                continue;
                        }

                        /* all other widgets */
                        in = is_connected_input_ep(w);
                        dapm_clear_walk(w->codec);
                        out = is_connected_output_ep(w);
                        dapm_clear_walk(w->codec);
                        power = (out != 0 && in != 0) ? 1 : 0;
                        power_change = (w->power == power) ? 0: 1;
                        w->power = power;

                        if (!power_change)
                                continue;

                        /* call any power change event handlers */
                        if (w->event)
                                pr_debug("power %s event for %s flags %x\n",
                                         w->power ? "on" : "off",
                                         w->name, w->event_flags);

                        /* power up pre event */
                        if (power && w->event &&
                            (w->event_flags & SND_SOC_DAPM_PRE_PMU)) {
                                ret = w->event(w, NULL, SND_SOC_DAPM_PRE_PMU);
                                if (ret < 0)
                                        return ret;
                        }

                        /* power down pre event */
                        if (!power && w->event &&
                            (w->event_flags & SND_SOC_DAPM_PRE_PMD)) {
                                ret = w->event(w, NULL, SND_SOC_DAPM_PRE_PMD);
                                if (ret < 0)
                                        return ret;
                        }

                        /* Lower PGA volume to reduce pops */
                        if (w->id == snd_soc_dapm_pga && !power)
                                dapm_set_pga(w, power);

                        dapm_update_bits(w);

                        /* Raise PGA volume to reduce pops */
                        if (w->id == snd_soc_dapm_pga && power)
                                dapm_set_pga(w, power);

                        /* power up post event */
                        if (power && w->event &&
                            (w->event_flags & SND_SOC_DAPM_POST_PMU)) {
                                ret = w->event(w,
                                               NULL, SND_SOC_DAPM_POST_PMU);
                                if (ret < 0)
                                        return ret;
                        }

                        /* power down post event */
                        if (!power && w->event &&
                            (w->event_flags & SND_SOC_DAPM_POST_PMD)) {
                                ret = w->event(w, NULL, SND_SOC_DAPM_POST_PMD);
                                if (ret < 0)
                                        return ret;
                        }
                }
        }

        return ret;
}

#ifdef DEBUG
static void dbg_dump_dapm(struct snd_soc_codec* codec, const char *action)
{
        struct snd_soc_dapm_widget *w;
        struct snd_soc_dapm_path *p = NULL;
        int in, out;

        printk("DAPM %s %s\n", codec->name, action);

        list_for_each_entry(w, &codec->dapm_widgets, list) {

                /* only display widgets that effect routing */
                switch (w->id) {
                case snd_soc_dapm_pre:
                case snd_soc_dapm_post:
                case snd_soc_dapm_vmid:
                        continue;
                case snd_soc_dapm_mux:
                case snd_soc_dapm_output:
                case snd_soc_dapm_input:
                case snd_soc_dapm_switch:
                case snd_soc_dapm_hp:
                case snd_soc_dapm_mic:
                case snd_soc_dapm_spk:
                case snd_soc_dapm_line:
                case snd_soc_dapm_micbias:
                case snd_soc_dapm_dac:
                case snd_soc_dapm_adc:
                case snd_soc_dapm_pga:
                case snd_soc_dapm_mixer:
                        if (w->name) {
                                in = is_connected_input_ep(w);
                                dapm_clear_walk(w->codec);
                                out = is_connected_output_ep(w);
                                dapm_clear_walk(w->codec);
                                printk("%s: %s  in %d out %d\n", w->name,
                                        w->power ? "On":"Off",in, out);

                                list_for_each_entry(p, &w->sources, list_sink) {
                                        if (p->connect)
                                                printk(" in  %s %s\n", p->name ? p->name : "static",
                                                        p->source->name);
                                }
                                list_for_each_entry(p, &w->sinks, list_source) {
                                        if (p->connect)
                                                printk(" out %s %s\n", p->name ? p->name : "static",
                                                        p->sink->name);
                                }
                        }
                break;
                }
        }
}
#endif

/* test and update the power status of a mux widget */
static int dapm_mux_update_power(struct snd_soc_dapm_widget *widget,
                                 struct snd_kcontrol *kcontrol, int mask,
                                 int mux, int val, struct soc_enum *e)
{
        struct snd_soc_dapm_path *path;
        int found = 0;

        if (widget->id != snd_soc_dapm_mux)
                return -ENODEV;

        if (!snd_soc_test_bits(widget->codec, e->reg, mask, val))
                return 0;

        /* find dapm widget path assoc with kcontrol */
        list_for_each_entry(path, &widget->codec->dapm_paths, list) {
                if (path->kcontrol != kcontrol)
                        continue;

                if (!path->name || !e->texts[mux])
                        continue;

                found = 1;
                /* we now need to match the string in the enum to the path */
                if (!(strcmp(path->name, e->texts[mux])))
                        path->connect = 1; /* new connection */
                else
                        path->connect = 0; /* old connection must be powered down */
        }

        if (found) {
                dapm_power_widgets(widget->codec, SND_SOC_DAPM_STREAM_NOP);
                dump_dapm(widget->codec, "mux power update");
        }

        return 0;
}

/* test and update the power status of a mixer or switch widget */
static int dapm_mixer_update_power(struct snd_soc_dapm_widget *widget,
                                   struct snd_kcontrol *kcontrol, int reg,
                                   int val_mask, int val, int invert)
{
        struct snd_soc_dapm_path *path;
        int found = 0;

        if (widget->id != snd_soc_dapm_mixer &&
            widget->id != snd_soc_dapm_switch)
                return -ENODEV;

        if (!snd_soc_test_bits(widget->codec, reg, val_mask, val))
                return 0;

        /* find dapm widget path assoc with kcontrol */
        list_for_each_entry(path, &widget->codec->dapm_paths, list) {
                if (path->kcontrol != kcontrol)
                        continue;

                /* found, now check type */
                found = 1;
                if (val)
                        /* new connection */
                        path->connect = invert ? 0:1;
                else
                        /* old connection must be powered down */
                        path->connect = invert ? 1:0;
                break;
        }

        if (found) {
                dapm_power_widgets(widget->codec, SND_SOC_DAPM_STREAM_NOP);
                dump_dapm(widget->codec, "mixer power update");
        }

        return 0;
}

/* show dapm widget status in sys fs */
static ssize_t dapm_widget_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
        struct snd_soc_device *devdata = dev_get_drvdata(dev);
        struct snd_soc_codec *codec = devdata->codec;
        struct snd_soc_dapm_widget *w;
        int count = 0;
        char *state = "not set";

        list_for_each_entry(w, &codec->dapm_widgets, list) {

                /* only display widgets that burnm power */
                switch (w->id) {
                case snd_soc_dapm_hp:
                case snd_soc_dapm_mic:
                case snd_soc_dapm_spk:
                case snd_soc_dapm_line:
                case snd_soc_dapm_micbias:
                case snd_soc_dapm_dac:
                case snd_soc_dapm_adc:
                case snd_soc_dapm_pga:
                case snd_soc_dapm_mixer:
                        if (w->name)
                                count += sprintf(buf + count, "%s: %s\n",
                                        w->name, w->power ? "On":"Off");
                break;
                default:
                break;
                }
        }

        switch (codec->bias_level) {
        case SND_SOC_BIAS_ON:
                state = "On";
                break;
        case SND_SOC_BIAS_PREPARE:
                state = "Prepare";
                break;
        case SND_SOC_BIAS_STANDBY:
                state = "Standby";
                break;
        case SND_SOC_BIAS_OFF:
                state = "Off";
                break;
        }
        count += sprintf(buf + count, "PM State: %s\n", state);

        return count;
}

static DEVICE_ATTR(dapm_widget, 0444, dapm_widget_show, NULL);

int snd_soc_dapm_sys_add(struct device *dev)
{
        int ret = 0;

        if (!dapm_status)
                return 0;

        ret = device_create_file(dev, &dev_attr_dapm_widget);
        if (ret != 0)
                return ret;

        asoc_debugfs = debugfs_create_dir("asoc", NULL);
        if (!IS_ERR(asoc_debugfs))
                debugfs_create_u32("dapm_pop_time", 0744, asoc_debugfs,
                                   &pop_time);
        else
                asoc_debugfs = NULL;

        return 0;
}

static void snd_soc_dapm_sys_remove(struct device *dev)
{
        if (dapm_status) {
                device_remove_file(dev, &dev_attr_dapm_widget);
        }

        if (asoc_debugfs)
                debugfs_remove_recursive(asoc_debugfs);
}

/* free all dapm widgets and resources */
static void dapm_free_widgets(struct snd_soc_codec *codec)
{
        struct snd_soc_dapm_widget *w, *next_w;
        struct snd_soc_dapm_path *p, *next_p;

        list_for_each_entry_safe(w, next_w, &codec->dapm_widgets, list) {
                list_del(&w->list);
                kfree(w);
        }

        list_for_each_entry_safe(p, next_p, &codec->dapm_paths, list) {
                list_del(&p->list);
                kfree(p->long_name);
                kfree(p);
        }
}

static int snd_soc_dapm_set_pin(struct snd_soc_codec *codec,
        char *pin, int status)
{
        struct snd_soc_dapm_widget *w;

        list_for_each_entry(w, &codec->dapm_widgets, list) {
                if (!strcmp(w->name, pin)) {
                        pr_debug("dapm: %s: pin %s\n", codec->name, pin);
                        w->connected = status;
                        return 0;
                }
        }

        pr_err("dapm: %s: configuring unknown pin %s\n", codec->name, pin);
        return -EINVAL;
}

/**
 * snd_soc_dapm_sync - scan and power dapm paths
 * @codec: audio codec
 *
 * Walks all dapm audio paths and powers widgets according to their
 * stream or path usage.
 *
 * Returns 0 for success.
 */
int snd_soc_dapm_sync(struct snd_soc_codec *codec)
{
        int ret = dapm_power_widgets(codec, SND_SOC_DAPM_STREAM_NOP);
        dump_dapm(codec, "sync");
        return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_sync);

static int snd_soc_dapm_add_route(struct snd_soc_codec *codec,
        const char *sink, const char *control, const char *source)
{
        struct snd_soc_dapm_path *path;
        struct snd_soc_dapm_widget *wsource = NULL, *wsink = NULL, *w;
        int ret = 0;

        /* find src and dest widgets */
        list_for_each_entry(w, &codec->dapm_widgets, list) {

                if (!wsink && !(strcmp(w->name, sink))) {
                        wsink = w;
                        continue;
                }
                if (!wsource && !(strcmp(w->name, source))) {
                        wsource = w;
                }
        }

        if (wsource == NULL || wsink == NULL)
                return -ENODEV;

        path = kzalloc(sizeof(struct snd_soc_dapm_path), GFP_KERNEL);
        if (!path)
                return -ENOMEM;

        path->source = wsource;
        path->sink = wsink;
        INIT_LIST_HEAD(&path->list);
        INIT_LIST_HEAD(&path->list_source);
        INIT_LIST_HEAD(&path->list_sink);

        /* check for external widgets */
        if (wsink->id == snd_soc_dapm_input) {
                if (wsource->id == snd_soc_dapm_micbias ||
                        wsource->id == snd_soc_dapm_mic ||
                        wsink->id == snd_soc_dapm_line ||
                        wsink->id == snd_soc_dapm_output)
                        wsink->ext = 1;
        }
        if (wsource->id == snd_soc_dapm_output) {
                if (wsink->id == snd_soc_dapm_spk ||
                        wsink->id == snd_soc_dapm_hp ||
                        wsink->id == snd_soc_dapm_line ||
                        wsink->id == snd_soc_dapm_input)
                        wsource->ext = 1;
        }

        /* connect static paths */
        if (control == NULL) {
                list_add(&path->list, &codec->dapm_paths);
                list_add(&path->list_sink, &wsink->sources);
                list_add(&path->list_source, &wsource->sinks);
                path->connect = 1;
                return 0;
        }

        /* connect dynamic paths */
        switch(wsink->id) {
        case snd_soc_dapm_adc:
        case snd_soc_dapm_dac:
        case snd_soc_dapm_pga:
        case snd_soc_dapm_input:
        case snd_soc_dapm_output:
        case snd_soc_dapm_micbias:
        case snd_soc_dapm_vmid:
        case snd_soc_dapm_pre:
        case snd_soc_dapm_post:
                list_add(&path->list, &codec->dapm_paths);
                list_add(&path->list_sink, &wsink->sources);
                list_add(&path->list_source, &wsource->sinks);
                path->connect = 1;
                return 0;
        case snd_soc_dapm_mux:
                ret = dapm_connect_mux(codec, wsource, wsink, path, control,
                        &wsink->kcontrols[0]);
                if (ret != 0)
                        goto err;
                break;
        case snd_soc_dapm_switch:
        case snd_soc_dapm_mixer:
                ret = dapm_connect_mixer(codec, wsource, wsink, path, control);
                if (ret != 0)
                        goto err;
                break;
        case snd_soc_dapm_hp:
        case snd_soc_dapm_mic:
        case snd_soc_dapm_line:
        case snd_soc_dapm_spk:
                list_add(&path->list, &codec->dapm_paths);
                list_add(&path->list_sink, &wsink->sources);
                list_add(&path->list_source, &wsource->sinks);
                path->connect = 0;
                return 0;
        }
        return 0;

err:
        printk(KERN_WARNING "asoc: no dapm match for %s --> %s --> %s\n", source,
                control, sink);
        kfree(path);
        return ret;
}

/**
 * snd_soc_dapm_connect_input - connect dapm widgets
 * @codec: audio codec
 * @sink: name of target widget
 * @control: mixer control name
 * @source: name of source name
 *
 * Connects 2 dapm widgets together via a named audio path. The sink is
 * the widget receiving the audio signal, whilst the source is the sender
 * of the audio signal.
 *
 * This function has been deprecated in favour of snd_soc_dapm_add_routes().
 *
 * Returns 0 for success else error.
 */
int snd_soc_dapm_connect_input(struct snd_soc_codec *codec, const char *sink,
        const char *control, const char *source)
{
        return snd_soc_dapm_add_route(codec, sink, control, source);
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_connect_input);

/**
 * snd_soc_dapm_add_routes - Add routes between DAPM widgets
 * @codec: codec
 * @route: audio routes
 * @num: number of routes
 *
 * Connects 2 dapm widgets together via a named audio path. The sink is
 * the widget receiving the audio signal, whilst the source is the sender
 * of the audio signal.
 *
 * Returns 0 for success else error. On error all resources can be freed
 * with a call to snd_soc_card_free().
 */
int snd_soc_dapm_add_routes(struct snd_soc_codec *codec,
                            const struct snd_soc_dapm_route *route, int num)
{
        int i, ret;

        for (i = 0; i < num; i++) {
                ret = snd_soc_dapm_add_route(codec, route->sink,
                                             route->control, route->source);
                if (ret < 0) {
                        printk(KERN_ERR "Failed to add route %s->%s\n",
                               route->source,
                               route->sink);
                        return ret;
                }
                route++;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_add_routes);

/**
 * snd_soc_dapm_new_widgets - add new dapm widgets
 * @codec: audio codec
 *
 * Checks the codec for any new dapm widgets and creates them if found.
 *
 * Returns 0 for success.
 */
int snd_soc_dapm_new_widgets(struct snd_soc_codec *codec)
{
        struct snd_soc_dapm_widget *w;

        list_for_each_entry(w, &codec->dapm_widgets, list)
        {
                if (w->new)
                        continue;

                switch(w->id) {
                case snd_soc_dapm_switch:
                case snd_soc_dapm_mixer:
                        dapm_new_mixer(codec, w);
                        break;
                case snd_soc_dapm_mux:
                        dapm_new_mux(codec, w);
                        break;
                case snd_soc_dapm_adc:
                case snd_soc_dapm_dac:
                case snd_soc_dapm_pga:
                        dapm_new_pga(codec, w);
                        break;
                case snd_soc_dapm_input:
                case snd_soc_dapm_output:
                case snd_soc_dapm_micbias:
                case snd_soc_dapm_spk:
                case snd_soc_dapm_hp:
                case snd_soc_dapm_mic:
                case snd_soc_dapm_line:
                case snd_soc_dapm_vmid:
                case snd_soc_dapm_pre:
                case snd_soc_dapm_post:
                        break;
                }
                w->new = 1;
        }

        dapm_power_widgets(codec, SND_SOC_DAPM_STREAM_NOP);
        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_new_widgets);

/**
 * snd_soc_dapm_get_volsw - dapm mixer get callback
 * @kcontrol: mixer control
 * @uinfo: control element information
 *
 * Callback to get the value of a dapm mixer control.
 *
 * Returns 0 for success.
 */
int snd_soc_dapm_get_volsw(struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_dapm_widget *widget = snd_kcontrol_chip(kcontrol);
        struct soc_mixer_control *mc =
                (struct soc_mixer_control *)kcontrol->private_value;
        unsigned int reg = mc->reg;
        unsigned int shift = mc->shift;
        unsigned int rshift = mc->rshift;
        int max = mc->max;
        unsigned int invert = mc->invert;
        unsigned int mask = (1 << fls(max)) - 1;

        /* return the saved value if we are powered down */
        if (widget->id == snd_soc_dapm_pga && !widget->power) {
                ucontrol->value.integer.value[0] = widget->saved_value;
                return 0;
        }

        ucontrol->value.integer.value[0] =
                (snd_soc_read(widget->codec, reg) >> shift) & mask;
        if (shift != rshift)
                ucontrol->value.integer.value[1] =
                        (snd_soc_read(widget->codec, reg) >> rshift) & mask;
        if (invert) {
                ucontrol->value.integer.value[0] =
                        max - ucontrol->value.integer.value[0];
                if (shift != rshift)
                        ucontrol->value.integer.value[1] =
                                max - ucontrol->value.integer.value[1];
        }

        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_get_volsw);

/**
 * snd_soc_dapm_put_volsw - dapm mixer set callback
 * @kcontrol: mixer control
 * @uinfo: control element information
 *
 * Callback to set the value of a dapm mixer control.
 *
 * Returns 0 for success.
 */
int snd_soc_dapm_put_volsw(struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_dapm_widget *widget = snd_kcontrol_chip(kcontrol);
        struct soc_mixer_control *mc =
                (struct soc_mixer_control *)kcontrol->private_value;
        unsigned int reg = mc->reg;
        unsigned int shift = mc->shift;
        unsigned int rshift = mc->rshift;
        int max = mc->max;
        unsigned int mask = (1 << fls(max)) - 1;
        unsigned int invert = mc->invert;
        unsigned short val, val2, val_mask;
        int ret;

        val = (ucontrol->value.integer.value[0] & mask);

        if (invert)
                val = max - val;
        val_mask = mask << shift;
        val = val << shift;
        if (shift != rshift) {
                val2 = (ucontrol->value.integer.value[1] & mask);
                if (invert)
                        val2 = max - val2;
                val_mask |= mask << rshift;
                val |= val2 << rshift;
        }

        mutex_lock(&widget->codec->mutex);
        widget->value = val;

        /* save volume value if the widget is powered down */
        if (widget->id == snd_soc_dapm_pga && !widget->power) {
                widget->saved_value = val;
                mutex_unlock(&widget->codec->mutex);
                return 1;
        }

        dapm_mixer_update_power(widget, kcontrol, reg, val_mask, val, invert);
        if (widget->event) {
                if (widget->event_flags & SND_SOC_DAPM_PRE_REG) {
                        ret = widget->event(widget, kcontrol,
                                                SND_SOC_DAPM_PRE_REG);
                        if (ret < 0) {
                                ret = 1;
                                goto out;
                        }
                }
                ret = snd_soc_update_bits(widget->codec, reg, val_mask, val);
                if (widget->event_flags & SND_SOC_DAPM_POST_REG)
                        ret = widget->event(widget, kcontrol,
                                                SND_SOC_DAPM_POST_REG);
        } else
                ret = snd_soc_update_bits(widget->codec, reg, val_mask, val);

out:
        mutex_unlock(&widget->codec->mutex);
        return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_put_volsw);

/**
 * snd_soc_dapm_get_enum_double - dapm enumerated double mixer get callback
 * @kcontrol: mixer control
 * @uinfo: control element information
 *
 * Callback to get the value of a dapm enumerated double mixer control.
 *
 * Returns 0 for success.
 */
int snd_soc_dapm_get_enum_double(struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_dapm_widget *widget = snd_kcontrol_chip(kcontrol);
        struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
        unsigned short val, bitmask;

        for (bitmask = 1; bitmask < e->max; bitmask <<= 1)
                ;
        val = snd_soc_read(widget->codec, e->reg);
        ucontrol->value.enumerated.item[0] = (val >> e->shift_l) & (bitmask - 1);
        if (e->shift_l != e->shift_r)
                ucontrol->value.enumerated.item[1] =
                        (val >> e->shift_r) & (bitmask - 1);

        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_get_enum_double);

/**
 * snd_soc_dapm_put_enum_double - dapm enumerated double mixer set callback
 * @kcontrol: mixer control
 * @uinfo: control element information
 *
 * Callback to set the value of a dapm enumerated double mixer control.
 *
 * Returns 0 for success.
 */
int snd_soc_dapm_put_enum_double(struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_dapm_widget *widget = snd_kcontrol_chip(kcontrol);
        struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
        unsigned short val, mux;
        unsigned short mask, bitmask;
        int ret = 0;

        for (bitmask = 1; bitmask < e->max; bitmask <<= 1)
                ;
        if (ucontrol->value.enumerated.item[0] > e->max - 1)
                return -EINVAL;
        mux = ucontrol->value.enumerated.item[0];
        val = mux << e->shift_l;
        mask = (bitmask - 1) << e->shift_l;
        if (e->shift_l != e->shift_r) {
                if (ucontrol->value.enumerated.item[1] > e->max - 1)
                        return -EINVAL;
                val |= ucontrol->value.enumerated.item[1] << e->shift_r;
                mask |= (bitmask - 1) << e->shift_r;
        }

        mutex_lock(&widget->codec->mutex);
        widget->value = val;
        dapm_mux_update_power(widget, kcontrol, mask, mux, val, e);
        if (widget->event) {
                if (widget->event_flags & SND_SOC_DAPM_PRE_REG) {
                        ret = widget->event(widget,
                                kcontrol, SND_SOC_DAPM_PRE_REG);
                        if (ret < 0)
                                goto out;
                }
                ret = snd_soc_update_bits(widget->codec, e->reg, mask, val);
                if (widget->event_flags & SND_SOC_DAPM_POST_REG)
                        ret = widget->event(widget,
                                kcontrol, SND_SOC_DAPM_POST_REG);
        } else
                ret = snd_soc_update_bits(widget->codec, e->reg, mask, val);

out:
        mutex_unlock(&widget->codec->mutex);
        return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_put_enum_double);

/**
 * snd_soc_dapm_new_control - create new dapm control
 * @codec: audio codec
 * @widget: widget template
 *
 * Creates a new dapm control based upon the template.
 *
 * Returns 0 for success else error.
 */
int snd_soc_dapm_new_control(struct snd_soc_codec *codec,
        const struct snd_soc_dapm_widget *widget)
{
        struct snd_soc_dapm_widget *w;

        if ((w = dapm_cnew_widget(widget)) == NULL)
                return -ENOMEM;

        w->codec = codec;
        INIT_LIST_HEAD(&w->sources);
        INIT_LIST_HEAD(&w->sinks);
        INIT_LIST_HEAD(&w->list);
        list_add(&w->list, &codec->dapm_widgets);

        /* machine layer set ups unconnected pins and insertions */
        w->connected = 1;
        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_new_control);

/**
 * snd_soc_dapm_new_controls - create new dapm controls
 * @codec: audio codec
 * @widget: widget array
 * @num: number of widgets
 *
 * Creates new DAPM controls based upon the templates.
 *
 * Returns 0 for success else error.
 */
int snd_soc_dapm_new_controls(struct snd_soc_codec *codec,
        const struct snd_soc_dapm_widget *widget,
        int num)
{
        int i, ret;

        for (i = 0; i < num; i++) {
                ret = snd_soc_dapm_new_control(codec, widget);
                if (ret < 0)
                        return ret;
                widget++;
        }
        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_new_controls);


/**
 * snd_soc_dapm_stream_event - send a stream event to the dapm core
 * @codec: audio codec
 * @stream: stream name
 * @event: stream event
 *
 * Sends a stream event to the dapm core. The core then makes any
 * necessary widget power changes.
 *
 * Returns 0 for success else error.
 */
int snd_soc_dapm_stream_event(struct snd_soc_codec *codec,
        char *stream, int event)
{
        struct snd_soc_dapm_widget *w;

        if (stream == NULL)
                return 0;

        mutex_lock(&codec->mutex);
        list_for_each_entry(w, &codec->dapm_widgets, list)
        {
                if (!w->sname)
                        continue;
                pr_debug("widget %s\n %s stream %s event %d\n",
                         w->name, w->sname, stream, event);
                if (strstr(w->sname, stream)) {
                        switch(event) {
                        case SND_SOC_DAPM_STREAM_START:
                                w->active = 1;
                                break;
                        case SND_SOC_DAPM_STREAM_STOP:
                                w->active = 0;
                                break;
                        case SND_SOC_DAPM_STREAM_SUSPEND:
                                if (w->active)
                                        w->suspend = 1;
                                w->active = 0;
                                break;
                        case SND_SOC_DAPM_STREAM_RESUME:
                                if (w->suspend) {
                                        w->active = 1;
                                        w->suspend = 0;
                                }
                                break;
                        case SND_SOC_DAPM_STREAM_PAUSE_PUSH:
                                break;
                        case SND_SOC_DAPM_STREAM_PAUSE_RELEASE:
                                break;
                        }
                }
        }
        mutex_unlock(&codec->mutex);

        dapm_power_widgets(codec, event);
        dump_dapm(codec, __func__);
        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_stream_event);

/**
 * snd_soc_dapm_set_bias_level - set the bias level for the system
 * @socdev: audio device
 * @level: level to configure
 *
 * Configure the bias (power) levels for the SoC audio device.
 *
 * Returns 0 for success else error.
 */
int snd_soc_dapm_set_bias_level(struct snd_soc_device *socdev,
                                enum snd_soc_bias_level level)
{
        struct snd_soc_codec *codec = socdev->codec;
        struct snd_soc_machine *machine = socdev->machine;
        int ret = 0;

        if (machine->set_bias_level)
                ret = machine->set_bias_level(machine, level);
        if (ret == 0 && codec->set_bias_level)
                ret = codec->set_bias_level(codec, level);

        return ret;
}

/**
 * snd_soc_dapm_enable_pin - enable pin.
 * @snd_soc_codec: SoC codec
 * @pin: pin name
 *
 * Enables input/output pin and it's parents or children widgets iff there is
 * a valid audio route and active audio stream.
 * NOTE: snd_soc_dapm_sync() needs to be called after this for DAPM to
 * do any widget power switching.
 */
int snd_soc_dapm_enable_pin(struct snd_soc_codec *codec, char *pin)
{
        return snd_soc_dapm_set_pin(codec, pin, 1);
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_enable_pin);

/**
 * snd_soc_dapm_disable_pin - disable pin.
 * @codec: SoC codec
 * @pin: pin name
 *
 * Disables input/output pin and it's parents or children widgets.
 * NOTE: snd_soc_dapm_sync() needs to be called after this for DAPM to
 * do any widget power switching.
 */
int snd_soc_dapm_disable_pin(struct snd_soc_codec *codec, char *pin)
{
        return snd_soc_dapm_set_pin(codec, pin, 0);
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_disable_pin);

/**
 * snd_soc_dapm_nc_pin - permanently disable pin.
 * @codec: SoC codec
 * @pin: pin name
 *
 * Marks the specified pin as being not connected, disabling it along
 * any parent or child widgets.  At present this is identical to
 * snd_soc_dapm_disable_pin() but in future it will be extended to do
 * additional things such as disabling controls which only affect
 * paths through the pin.
 *
 * NOTE: snd_soc_dapm_sync() needs to be called after this for DAPM to
 * do any widget power switching.
 */
int snd_soc_dapm_nc_pin(struct snd_soc_codec *codec, char *pin)
{
        return snd_soc_dapm_set_pin(codec, pin, 0);
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_nc_pin);

/**
 * snd_soc_dapm_get_pin_status - get audio pin status
 * @codec: audio codec
 * @pin: audio signal pin endpoint (or start point)
 *
 * Get audio pin status - connected or disconnected.
 *
 * Returns 1 for connected otherwise 0.
 */
int snd_soc_dapm_get_pin_status(struct snd_soc_codec *codec, char *pin)
{
        struct snd_soc_dapm_widget *w;

        list_for_each_entry(w, &codec->dapm_widgets, list) {
                if (!strcmp(w->name, pin))
                        return w->connected;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_get_pin_status);

/**
 * snd_soc_dapm_free - free dapm resources
 * @socdev: SoC device
 *
 * Free all dapm widgets and resources.
 */
void snd_soc_dapm_free(struct snd_soc_device *socdev)
{
        struct snd_soc_codec *codec = socdev->codec;

        snd_soc_dapm_sys_remove(socdev->dev);
        dapm_free_widgets(codec);
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_free);

/* Module information */
MODULE_AUTHOR("Liam Girdwood, lrg@slimlogic.co.uk");
MODULE_DESCRIPTION("Dynamic Audio Power Management core for ALSA SoC");
MODULE_LICENSE("GPL");

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