satip-axe/kernel/sound/stm/conv_gpio.c
2015-03-26 17:24:57 +01:00

418 lines
10 KiB
C

/*
* STMicroelectronics System-on-Chips' GPIO-controlled ADC/DAC driver
*
* Copyright (c) 2005-2011 STMicroelectronics Limited
*
* Author: Pawel Moll <pawel.moll@st.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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* 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/io.h>
#include <linux/platform_device.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/gpio.h>
#include <sound/core.h>
#include <sound/info.h>
#include <sound/stm.h>
#include "common.h"
static int snd_stm_debug_level;
module_param_named(debug, snd_stm_debug_level, int, S_IRUGO | S_IWUSR);
/*
* Internal DAC instance structure
*/
struct snd_stm_conv_gpio {
/* System informations */
const char *dev_name;
struct snd_stm_conv_converter *converter;
struct snd_stm_conv_gpio_info *info;
struct snd_stm_conv_ops ops;
/* Runtime data */
int may_sleep;
struct work_struct work; /* Used if may_sleep */
int work_enable_value;
int work_mute_value;
spinlock_t work_lock; /* Protects work_*_value */
struct snd_info_entry *proc_entry;
snd_stm_magic_field;
};
/*
* Sleeping-safe GPIO access implementation
*/
static void snd_stm_conv_gpio_work(struct work_struct *work)
{
struct snd_stm_conv_gpio *conv_gpio = container_of(work,
struct snd_stm_conv_gpio, work);
int enable_value, mute_value;
snd_stm_printd(1, "snd_stm_conv_gpio_work(work=%p)\n", work);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
spin_lock(&conv_gpio->work_lock);
enable_value = conv_gpio->work_enable_value;
conv_gpio->work_enable_value = -1;
mute_value = conv_gpio->work_mute_value;
conv_gpio->work_mute_value = -1;
spin_unlock(&conv_gpio->work_lock);
if (enable_value != -1)
gpio_set_value_cansleep(conv_gpio->info->enable_gpio,
enable_value);
if (mute_value != -1)
gpio_set_value_cansleep(conv_gpio->info->mute_gpio,
mute_value);
}
static void snd_stm_conv_gpio_set_value(struct snd_stm_conv_gpio *conv_gpio,
int enable_not_mute, int value)
{
snd_stm_printd(1, "snd_stm_conv_gpio_set_value(conv_gpio=%p, "
"enable_not_mute=%d, value=%d)\n",
conv_gpio, enable_not_mute, value);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
if (conv_gpio->may_sleep) {
spin_lock(&conv_gpio->work_lock);
if (enable_not_mute)
conv_gpio->work_enable_value = value;
else
conv_gpio->work_mute_value = value;
schedule_work(&conv_gpio->work);
spin_unlock(&conv_gpio->work_lock);
} else {
gpio_set_value(enable_not_mute ? conv_gpio->info->enable_gpio :
conv_gpio->info->mute_gpio, value);
}
}
/*
* Converter interface implementation
*/
static unsigned int snd_stm_conv_gpio_get_format(void *priv)
{
struct snd_stm_conv_gpio *conv_gpio = priv;
snd_stm_printd(1, "snd_stm_conv_gpio_get_format(priv=%p)\n", priv);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
return conv_gpio->info->format;
}
static int snd_stm_conv_gpio_get_oversampling(void *priv)
{
struct snd_stm_conv_gpio *conv_gpio = priv;
snd_stm_printd(1, "snd_stm_conv_gpio_get_oversampling(priv=%p)\n",
priv);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
return conv_gpio->info->oversampling;
}
static int snd_stm_conv_gpio_set_enabled(int enabled, void *priv)
{
struct snd_stm_conv_gpio *conv_gpio = priv;
snd_stm_printd(1, "snd_stm_conv_gpio_enable(enabled=%d, priv=%p)\n",
enabled, priv);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
BUG_ON(!conv_gpio->info->enable_supported);
snd_stm_printd(1, "%sabling DAC %s's.\n", enabled ? "En" : "Dis",
conv_gpio->dev_name);
snd_stm_conv_gpio_set_value(conv_gpio, 1,
enabled ? conv_gpio->info->enable_value :
!conv_gpio->info->enable_value);
return 0;
}
static int snd_stm_conv_gpio_set_muted(int muted, void *priv)
{
struct snd_stm_conv_gpio *conv_gpio = priv;
snd_stm_printd(1, "snd_stm_conv_gpio_set_muted(muted=%d, priv=%p)\n",
muted, priv);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
BUG_ON(!conv_gpio->info->mute_supported);
snd_stm_printd(1, "%suting DAC %s.\n", muted ? "M" : "Unm",
conv_gpio->dev_name);
snd_stm_conv_gpio_set_value(conv_gpio, 0,
muted ? conv_gpio->info->mute_value :
!conv_gpio->info->mute_value);
return 0;
}
/*
* Procfs status callback
*/
static void snd_stm_conv_gpio_read_info(struct snd_info_entry *entry,
struct snd_info_buffer *buffer)
{
struct snd_stm_conv_gpio *conv_gpio = entry->private_data;
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
snd_iprintf(buffer, "--- %s ---\n", conv_gpio->dev_name);
snd_iprintf(buffer, "enable_gpio(%d) = %d\n",
conv_gpio->info->enable_gpio,
gpio_get_value(conv_gpio->info->enable_gpio));
if (conv_gpio->info->mute_supported)
snd_iprintf(buffer, "mute_gpio(%d) = %d\n",
conv_gpio->info->mute_gpio,
gpio_get_value(conv_gpio->info->mute_gpio));
snd_iprintf(buffer, "\n");
}
/*
* Platform driver routines
*/
static int snd_stm_conv_gpio_probe(struct platform_device *pdev)
{
int result = 0;
struct snd_stm_conv_gpio *conv_gpio;
snd_stm_printd(0, "%s('%s')\n", __func__, dev_name(&pdev->dev));
BUG_ON(!pdev->dev.platform_data);
conv_gpio = kzalloc(sizeof(*conv_gpio), GFP_KERNEL);
if (!conv_gpio) {
snd_stm_printe("Can't allocate memory "
"for a device description!\n");
result = -ENOMEM;
goto error_alloc;
}
snd_stm_magic_set(conv_gpio);
conv_gpio->dev_name = dev_name(&pdev->dev);
conv_gpio->info = pdev->dev.platform_data;
conv_gpio->ops.get_format = snd_stm_conv_gpio_get_format;
conv_gpio->ops.get_oversampling = snd_stm_conv_gpio_get_oversampling;
if (conv_gpio->info->enable_supported)
conv_gpio->ops.set_enabled = snd_stm_conv_gpio_set_enabled;
if (conv_gpio->info->mute_supported)
conv_gpio->ops.set_muted = snd_stm_conv_gpio_set_muted;
/* Get connections */
BUG_ON(!conv_gpio->info->source_bus_id);
snd_stm_printd(0, "This DAC is attached to PCM player '%s'.\n",
conv_gpio->info->source_bus_id);
conv_gpio->converter = snd_stm_conv_register_converter(
conv_gpio->info->group, &conv_gpio->ops, conv_gpio,
&platform_bus_type, conv_gpio->info->source_bus_id,
conv_gpio->info->channel_from,
conv_gpio->info->channel_to, NULL);
if (!conv_gpio->converter) {
snd_stm_printe("Can't attach to PCM player!\n");
result = -EINVAL;
goto error_attach;
}
/* Reserve & initialize GPIO lines (enabled & mute) */
if (conv_gpio->info->enable_supported) {
result = gpio_request(conv_gpio->info->enable_gpio,
conv_gpio->dev_name);
if (result != 0) {
snd_stm_printe("Can't reserve 'enable' GPIO line!\n");
goto error_gpio_request_enable;
}
if (gpio_direction_output(conv_gpio->info->enable_gpio,
!conv_gpio->info->enable_value) != 0) {
snd_stm_printe("Can't set 'enable' GPIO line as "
"output!\n");
goto error_gpio_direction_output_enable;
}
conv_gpio->may_sleep = gpio_cansleep(
conv_gpio->info->enable_gpio);
}
if (conv_gpio->info->mute_supported) {
result = gpio_request(conv_gpio->info->mute_gpio,
conv_gpio->dev_name);
if (result != 0) {
snd_stm_printe("Can't reserve 'mute' GPIO line!\n");
goto error_gpio_request_mute;
}
if (gpio_direction_output(conv_gpio->info->mute_gpio,
conv_gpio->info->mute_value) != 0) {
snd_stm_printe("Can't set 'mute' GPIO line as output!"
"\n");
goto error_gpio_direction_output_mute;
}
conv_gpio->may_sleep |= gpio_cansleep(
conv_gpio->info->mute_gpio);
}
if (conv_gpio->may_sleep) {
INIT_WORK(&conv_gpio->work, snd_stm_conv_gpio_work);
spin_lock_init(&conv_gpio->work_lock);
conv_gpio->work_enable_value = -1;
conv_gpio->work_mute_value = -1;
}
/* Additional procfs info */
snd_stm_info_register(&conv_gpio->proc_entry,
conv_gpio->dev_name,
snd_stm_conv_gpio_read_info,
conv_gpio);
/* Done now */
platform_set_drvdata(pdev, conv_gpio);
return 0;
error_gpio_direction_output_mute:
if (conv_gpio->info->mute_supported)
gpio_free(conv_gpio->info->mute_gpio);
error_gpio_request_mute:
error_gpio_direction_output_enable:
if (conv_gpio->info->enable_supported)
gpio_free(conv_gpio->info->enable_gpio);
error_gpio_request_enable:
snd_stm_conv_unregister_converter(conv_gpio->converter);
error_attach:
snd_stm_magic_clear(conv_gpio);
kfree(conv_gpio);
error_alloc:
return result;
}
static int snd_stm_conv_gpio_remove(struct platform_device *pdev)
{
struct snd_stm_conv_gpio *conv_gpio = platform_get_drvdata(pdev);
BUG_ON(!conv_gpio);
BUG_ON(!snd_stm_magic_valid(conv_gpio));
snd_stm_conv_unregister_converter(conv_gpio->converter);
/* Remove procfs entry */
snd_stm_info_unregister(conv_gpio->proc_entry);
/* Wait for the possibly scheduled work... */
if (conv_gpio->may_sleep)
flush_scheduled_work();
/* Muting and disabling - just to be sure ;-) */
if (conv_gpio->info->mute_supported) {
gpio_set_value_cansleep(conv_gpio->info->mute_gpio,
conv_gpio->info->mute_value);
gpio_free(conv_gpio->info->mute_gpio);
}
if (conv_gpio->info->enable_supported) {
gpio_set_value_cansleep(conv_gpio->info->enable_gpio,
!conv_gpio->info->enable_value);
gpio_free(conv_gpio->info->enable_gpio);
}
snd_stm_magic_clear(conv_gpio);
kfree(conv_gpio);
return 0;
}
static struct platform_driver snd_stm_conv_gpio_driver = {
.driver.name = "snd_conv_gpio",
.probe = snd_stm_conv_gpio_probe,
.remove = snd_stm_conv_gpio_remove,
};
/*
* Initialization
*/
static int __init snd_stm_conv_gpio_init(void)
{
return platform_driver_register(&snd_stm_conv_gpio_driver);
}
static void __exit snd_stm_conv_gpio_exit(void)
{
platform_driver_unregister(&snd_stm_conv_gpio_driver);
}
MODULE_AUTHOR("Pawel Moll <pawel.moll@st.com>");
MODULE_DESCRIPTION("STMicroelectronics GPIO-controlled audio converter driver");
MODULE_LICENSE("GPL");
module_init(snd_stm_conv_gpio_init);
module_exit(snd_stm_conv_gpio_exit);