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linux/drivers/mfd/wm8350-core.c
Mark Brown 5051d411ec mfd: Clean up after WM83xx AUXADC interrupt if it arrives late
In certain circumstances, especially under heavy load, the AUXADC
completion interrupt may be detected after we've timed out waiting for
it.  That conversion would still succeed but the next conversion will
see the completion that was signalled by the interrupt for the previous
conversion and therefore not wait for the AUXADC conversion to run,
causing it to report failure.

Provide a simple, non-invasive cleanup by using try_wait_for_completion()
to ensure that the completion is not signalled before we wait.  Since
the AUXADC is run within a mutex we know there can only have been at
most one AUXADC interrupt outstanding.  A more involved change should
follow for the next merge window.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2010-05-13 12:58:55 +02:00

775 lines
18 KiB
C

/*
* wm8350-core.c -- Device access for Wolfson WM8350
*
* Copyright 2007, 2008 Wolfson Microelectronics PLC.
*
* Author: Liam Girdwood, Mark Brown
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/bug.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/mfd/wm8350/core.h>
#include <linux/mfd/wm8350/audio.h>
#include <linux/mfd/wm8350/comparator.h>
#include <linux/mfd/wm8350/gpio.h>
#include <linux/mfd/wm8350/pmic.h>
#include <linux/mfd/wm8350/rtc.h>
#include <linux/mfd/wm8350/supply.h>
#include <linux/mfd/wm8350/wdt.h>
#define WM8350_UNLOCK_KEY 0x0013
#define WM8350_LOCK_KEY 0x0000
#define WM8350_CLOCK_CONTROL_1 0x28
#define WM8350_AIF_TEST 0x74
/* debug */
#define WM8350_BUS_DEBUG 0
#if WM8350_BUS_DEBUG
#define dump(regs, src) do { \
int i_; \
u16 *src_ = src; \
printk(KERN_DEBUG); \
for (i_ = 0; i_ < regs; i_++) \
printk(" 0x%4.4x", *src_++); \
printk("\n"); \
} while (0);
#else
#define dump(bytes, src)
#endif
#define WM8350_LOCK_DEBUG 0
#if WM8350_LOCK_DEBUG
#define ldbg(format, arg...) printk(format, ## arg)
#else
#define ldbg(format, arg...)
#endif
/*
* WM8350 Device IO
*/
static DEFINE_MUTEX(io_mutex);
static DEFINE_MUTEX(reg_lock_mutex);
/* Perform a physical read from the device.
*/
static int wm8350_phys_read(struct wm8350 *wm8350, u8 reg, int num_regs,
u16 *dest)
{
int i, ret;
int bytes = num_regs * 2;
dev_dbg(wm8350->dev, "volatile read\n");
ret = wm8350->read_dev(wm8350, reg, bytes, (char *)dest);
for (i = reg; i < reg + num_regs; i++) {
/* Cache is CPU endian */
dest[i - reg] = be16_to_cpu(dest[i - reg]);
/* Mask out non-readable bits */
dest[i - reg] &= wm8350_reg_io_map[i].readable;
}
dump(num_regs, dest);
return ret;
}
static int wm8350_read(struct wm8350 *wm8350, u8 reg, int num_regs, u16 *dest)
{
int i;
int end = reg + num_regs;
int ret = 0;
int bytes = num_regs * 2;
if (wm8350->read_dev == NULL)
return -ENODEV;
if ((reg + num_regs - 1) > WM8350_MAX_REGISTER) {
dev_err(wm8350->dev, "invalid reg %x\n",
reg + num_regs - 1);
return -EINVAL;
}
dev_dbg(wm8350->dev,
"%s R%d(0x%2.2x) %d regs\n", __func__, reg, reg, num_regs);
#if WM8350_BUS_DEBUG
/* we can _safely_ read any register, but warn if read not supported */
for (i = reg; i < end; i++) {
if (!wm8350_reg_io_map[i].readable)
dev_warn(wm8350->dev,
"reg R%d is not readable\n", i);
}
#endif
/* if any volatile registers are required, then read back all */
for (i = reg; i < end; i++)
if (wm8350_reg_io_map[i].vol)
return wm8350_phys_read(wm8350, reg, num_regs, dest);
/* no volatiles, then cache is good */
dev_dbg(wm8350->dev, "cache read\n");
memcpy(dest, &wm8350->reg_cache[reg], bytes);
dump(num_regs, dest);
return ret;
}
static inline int is_reg_locked(struct wm8350 *wm8350, u8 reg)
{
if (reg == WM8350_SECURITY ||
wm8350->reg_cache[WM8350_SECURITY] == WM8350_UNLOCK_KEY)
return 0;
if ((reg >= WM8350_GPIO_FUNCTION_SELECT_1 &&
reg <= WM8350_GPIO_FUNCTION_SELECT_4) ||
(reg >= WM8350_BATTERY_CHARGER_CONTROL_1 &&
reg <= WM8350_BATTERY_CHARGER_CONTROL_3))
return 1;
return 0;
}
static int wm8350_write(struct wm8350 *wm8350, u8 reg, int num_regs, u16 *src)
{
int i;
int end = reg + num_regs;
int bytes = num_regs * 2;
if (wm8350->write_dev == NULL)
return -ENODEV;
if ((reg + num_regs - 1) > WM8350_MAX_REGISTER) {
dev_err(wm8350->dev, "invalid reg %x\n",
reg + num_regs - 1);
return -EINVAL;
}
/* it's generally not a good idea to write to RO or locked registers */
for (i = reg; i < end; i++) {
if (!wm8350_reg_io_map[i].writable) {
dev_err(wm8350->dev,
"attempted write to read only reg R%d\n", i);
return -EINVAL;
}
if (is_reg_locked(wm8350, i)) {
dev_err(wm8350->dev,
"attempted write to locked reg R%d\n", i);
return -EINVAL;
}
src[i - reg] &= wm8350_reg_io_map[i].writable;
wm8350->reg_cache[i] =
(wm8350->reg_cache[i] & ~wm8350_reg_io_map[i].writable)
| src[i - reg];
src[i - reg] = cpu_to_be16(src[i - reg]);
}
/* Actually write it out */
return wm8350->write_dev(wm8350, reg, bytes, (char *)src);
}
/*
* Safe read, modify, write methods
*/
int wm8350_clear_bits(struct wm8350 *wm8350, u16 reg, u16 mask)
{
u16 data;
int err;
mutex_lock(&io_mutex);
err = wm8350_read(wm8350, reg, 1, &data);
if (err) {
dev_err(wm8350->dev, "read from reg R%d failed\n", reg);
goto out;
}
data &= ~mask;
err = wm8350_write(wm8350, reg, 1, &data);
if (err)
dev_err(wm8350->dev, "write to reg R%d failed\n", reg);
out:
mutex_unlock(&io_mutex);
return err;
}
EXPORT_SYMBOL_GPL(wm8350_clear_bits);
int wm8350_set_bits(struct wm8350 *wm8350, u16 reg, u16 mask)
{
u16 data;
int err;
mutex_lock(&io_mutex);
err = wm8350_read(wm8350, reg, 1, &data);
if (err) {
dev_err(wm8350->dev, "read from reg R%d failed\n", reg);
goto out;
}
data |= mask;
err = wm8350_write(wm8350, reg, 1, &data);
if (err)
dev_err(wm8350->dev, "write to reg R%d failed\n", reg);
out:
mutex_unlock(&io_mutex);
return err;
}
EXPORT_SYMBOL_GPL(wm8350_set_bits);
u16 wm8350_reg_read(struct wm8350 *wm8350, int reg)
{
u16 data;
int err;
mutex_lock(&io_mutex);
err = wm8350_read(wm8350, reg, 1, &data);
if (err)
dev_err(wm8350->dev, "read from reg R%d failed\n", reg);
mutex_unlock(&io_mutex);
return data;
}
EXPORT_SYMBOL_GPL(wm8350_reg_read);
int wm8350_reg_write(struct wm8350 *wm8350, int reg, u16 val)
{
int ret;
u16 data = val;
mutex_lock(&io_mutex);
ret = wm8350_write(wm8350, reg, 1, &data);
if (ret)
dev_err(wm8350->dev, "write to reg R%d failed\n", reg);
mutex_unlock(&io_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(wm8350_reg_write);
int wm8350_block_read(struct wm8350 *wm8350, int start_reg, int regs,
u16 *dest)
{
int err = 0;
mutex_lock(&io_mutex);
err = wm8350_read(wm8350, start_reg, regs, dest);
if (err)
dev_err(wm8350->dev, "block read starting from R%d failed\n",
start_reg);
mutex_unlock(&io_mutex);
return err;
}
EXPORT_SYMBOL_GPL(wm8350_block_read);
int wm8350_block_write(struct wm8350 *wm8350, int start_reg, int regs,
u16 *src)
{
int ret = 0;
mutex_lock(&io_mutex);
ret = wm8350_write(wm8350, start_reg, regs, src);
if (ret)
dev_err(wm8350->dev, "block write starting at R%d failed\n",
start_reg);
mutex_unlock(&io_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(wm8350_block_write);
/**
* wm8350_reg_lock()
*
* The WM8350 has a hardware lock which can be used to prevent writes to
* some registers (generally those which can cause particularly serious
* problems if misused). This function enables that lock.
*/
int wm8350_reg_lock(struct wm8350 *wm8350)
{
u16 key = WM8350_LOCK_KEY;
int ret;
ldbg(__func__);
mutex_lock(&io_mutex);
ret = wm8350_write(wm8350, WM8350_SECURITY, 1, &key);
if (ret)
dev_err(wm8350->dev, "lock failed\n");
mutex_unlock(&io_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(wm8350_reg_lock);
/**
* wm8350_reg_unlock()
*
* The WM8350 has a hardware lock which can be used to prevent writes to
* some registers (generally those which can cause particularly serious
* problems if misused). This function disables that lock so updates
* can be performed. For maximum safety this should be done only when
* required.
*/
int wm8350_reg_unlock(struct wm8350 *wm8350)
{
u16 key = WM8350_UNLOCK_KEY;
int ret;
ldbg(__func__);
mutex_lock(&io_mutex);
ret = wm8350_write(wm8350, WM8350_SECURITY, 1, &key);
if (ret)
dev_err(wm8350->dev, "unlock failed\n");
mutex_unlock(&io_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(wm8350_reg_unlock);
int wm8350_read_auxadc(struct wm8350 *wm8350, int channel, int scale, int vref)
{
u16 reg, result = 0;
if (channel < WM8350_AUXADC_AUX1 || channel > WM8350_AUXADC_TEMP)
return -EINVAL;
if (channel >= WM8350_AUXADC_USB && channel <= WM8350_AUXADC_TEMP
&& (scale != 0 || vref != 0))
return -EINVAL;
mutex_lock(&wm8350->auxadc_mutex);
/* Turn on the ADC */
reg = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5);
wm8350_reg_write(wm8350, WM8350_POWER_MGMT_5, reg | WM8350_AUXADC_ENA);
if (scale || vref) {
reg = scale << 13;
reg |= vref << 12;
wm8350_reg_write(wm8350, WM8350_AUX1_READBACK + channel, reg);
}
reg = wm8350_reg_read(wm8350, WM8350_DIGITISER_CONTROL_1);
reg |= 1 << channel | WM8350_AUXADC_POLL;
wm8350_reg_write(wm8350, WM8350_DIGITISER_CONTROL_1, reg);
/* If a late IRQ left the completion signalled then consume
* the completion. */
try_wait_for_completion(&wm8350->auxadc_done);
/* We ignore the result of the completion and just check for a
* conversion result, allowing us to soldier on if the IRQ
* infrastructure is not set up for the chip. */
wait_for_completion_timeout(&wm8350->auxadc_done, msecs_to_jiffies(5));
reg = wm8350_reg_read(wm8350, WM8350_DIGITISER_CONTROL_1);
if (reg & WM8350_AUXADC_POLL)
dev_err(wm8350->dev, "adc chn %d read timeout\n", channel);
else
result = wm8350_reg_read(wm8350,
WM8350_AUX1_READBACK + channel);
/* Turn off the ADC */
reg = wm8350_reg_read(wm8350, WM8350_POWER_MGMT_5);
wm8350_reg_write(wm8350, WM8350_POWER_MGMT_5,
reg & ~WM8350_AUXADC_ENA);
mutex_unlock(&wm8350->auxadc_mutex);
return result & WM8350_AUXADC_DATA1_MASK;
}
EXPORT_SYMBOL_GPL(wm8350_read_auxadc);
static irqreturn_t wm8350_auxadc_irq(int irq, void *irq_data)
{
struct wm8350 *wm8350 = irq_data;
complete(&wm8350->auxadc_done);
return IRQ_HANDLED;
}
/*
* Cache is always host endian.
*/
static int wm8350_create_cache(struct wm8350 *wm8350, int type, int mode)
{
int i, ret = 0;
u16 value;
const u16 *reg_map;
switch (type) {
case 0:
switch (mode) {
#ifdef CONFIG_MFD_WM8350_CONFIG_MODE_0
case 0:
reg_map = wm8350_mode0_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8350_CONFIG_MODE_1
case 1:
reg_map = wm8350_mode1_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8350_CONFIG_MODE_2
case 2:
reg_map = wm8350_mode2_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8350_CONFIG_MODE_3
case 3:
reg_map = wm8350_mode3_defaults;
break;
#endif
default:
dev_err(wm8350->dev,
"WM8350 configuration mode %d not supported\n",
mode);
return -EINVAL;
}
break;
case 1:
switch (mode) {
#ifdef CONFIG_MFD_WM8351_CONFIG_MODE_0
case 0:
reg_map = wm8351_mode0_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8351_CONFIG_MODE_1
case 1:
reg_map = wm8351_mode1_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8351_CONFIG_MODE_2
case 2:
reg_map = wm8351_mode2_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8351_CONFIG_MODE_3
case 3:
reg_map = wm8351_mode3_defaults;
break;
#endif
default:
dev_err(wm8350->dev,
"WM8351 configuration mode %d not supported\n",
mode);
return -EINVAL;
}
break;
case 2:
switch (mode) {
#ifdef CONFIG_MFD_WM8352_CONFIG_MODE_0
case 0:
reg_map = wm8352_mode0_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8352_CONFIG_MODE_1
case 1:
reg_map = wm8352_mode1_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8352_CONFIG_MODE_2
case 2:
reg_map = wm8352_mode2_defaults;
break;
#endif
#ifdef CONFIG_MFD_WM8352_CONFIG_MODE_3
case 3:
reg_map = wm8352_mode3_defaults;
break;
#endif
default:
dev_err(wm8350->dev,
"WM8352 configuration mode %d not supported\n",
mode);
return -EINVAL;
}
break;
default:
dev_err(wm8350->dev,
"WM835x configuration mode %d not supported\n",
mode);
return -EINVAL;
}
wm8350->reg_cache =
kmalloc(sizeof(u16) * (WM8350_MAX_REGISTER + 1), GFP_KERNEL);
if (wm8350->reg_cache == NULL)
return -ENOMEM;
/* Read the initial cache state back from the device - this is
* a PMIC so the device many not be in a virgin state and we
* can't rely on the silicon values.
*/
ret = wm8350->read_dev(wm8350, 0,
sizeof(u16) * (WM8350_MAX_REGISTER + 1),
wm8350->reg_cache);
if (ret < 0) {
dev_err(wm8350->dev,
"failed to read initial cache values\n");
goto out;
}
/* Mask out uncacheable/unreadable bits and the audio. */
for (i = 0; i < WM8350_MAX_REGISTER; i++) {
if (wm8350_reg_io_map[i].readable &&
(i < WM8350_CLOCK_CONTROL_1 || i > WM8350_AIF_TEST)) {
value = be16_to_cpu(wm8350->reg_cache[i]);
value &= wm8350_reg_io_map[i].readable;
wm8350->reg_cache[i] = value;
} else
wm8350->reg_cache[i] = reg_map[i];
}
out:
return ret;
}
/*
* Register a client device. This is non-fatal since there is no need to
* fail the entire device init due to a single platform device failing.
*/
static void wm8350_client_dev_register(struct wm8350 *wm8350,
const char *name,
struct platform_device **pdev)
{
int ret;
*pdev = platform_device_alloc(name, -1);
if (*pdev == NULL) {
dev_err(wm8350->dev, "Failed to allocate %s\n", name);
return;
}
(*pdev)->dev.parent = wm8350->dev;
platform_set_drvdata(*pdev, wm8350);
ret = platform_device_add(*pdev);
if (ret != 0) {
dev_err(wm8350->dev, "Failed to register %s: %d\n", name, ret);
platform_device_put(*pdev);
*pdev = NULL;
}
}
int wm8350_device_init(struct wm8350 *wm8350, int irq,
struct wm8350_platform_data *pdata)
{
int ret;
u16 id1, id2, mask_rev;
u16 cust_id, mode, chip_rev;
/* get WM8350 revision and config mode */
ret = wm8350->read_dev(wm8350, WM8350_RESET_ID, sizeof(id1), &id1);
if (ret != 0) {
dev_err(wm8350->dev, "Failed to read ID: %d\n", ret);
goto err;
}
ret = wm8350->read_dev(wm8350, WM8350_ID, sizeof(id2), &id2);
if (ret != 0) {
dev_err(wm8350->dev, "Failed to read ID: %d\n", ret);
goto err;
}
ret = wm8350->read_dev(wm8350, WM8350_REVISION, sizeof(mask_rev),
&mask_rev);
if (ret != 0) {
dev_err(wm8350->dev, "Failed to read revision: %d\n", ret);
goto err;
}
id1 = be16_to_cpu(id1);
id2 = be16_to_cpu(id2);
mask_rev = be16_to_cpu(mask_rev);
if (id1 != 0x6143) {
dev_err(wm8350->dev,
"Device with ID %x is not a WM8350\n", id1);
ret = -ENODEV;
goto err;
}
mode = id2 & WM8350_CONF_STS_MASK >> 10;
cust_id = id2 & WM8350_CUST_ID_MASK;
chip_rev = (id2 & WM8350_CHIP_REV_MASK) >> 12;
dev_info(wm8350->dev,
"CONF_STS %d, CUST_ID %d, MASK_REV %d, CHIP_REV %d\n",
mode, cust_id, mask_rev, chip_rev);
if (cust_id != 0) {
dev_err(wm8350->dev, "Unsupported CUST_ID\n");
ret = -ENODEV;
goto err;
}
switch (mask_rev) {
case 0:
wm8350->pmic.max_dcdc = WM8350_DCDC_6;
wm8350->pmic.max_isink = WM8350_ISINK_B;
switch (chip_rev) {
case WM8350_REV_E:
dev_info(wm8350->dev, "WM8350 Rev E\n");
break;
case WM8350_REV_F:
dev_info(wm8350->dev, "WM8350 Rev F\n");
break;
case WM8350_REV_G:
dev_info(wm8350->dev, "WM8350 Rev G\n");
wm8350->power.rev_g_coeff = 1;
break;
case WM8350_REV_H:
dev_info(wm8350->dev, "WM8350 Rev H\n");
wm8350->power.rev_g_coeff = 1;
break;
default:
/* For safety we refuse to run on unknown hardware */
dev_err(wm8350->dev, "Unknown WM8350 CHIP_REV\n");
ret = -ENODEV;
goto err;
}
break;
case 1:
wm8350->pmic.max_dcdc = WM8350_DCDC_4;
wm8350->pmic.max_isink = WM8350_ISINK_A;
switch (chip_rev) {
case 0:
dev_info(wm8350->dev, "WM8351 Rev A\n");
wm8350->power.rev_g_coeff = 1;
break;
case 1:
dev_info(wm8350->dev, "WM8351 Rev B\n");
wm8350->power.rev_g_coeff = 1;
break;
default:
dev_err(wm8350->dev, "Unknown WM8351 CHIP_REV\n");
ret = -ENODEV;
goto err;
}
break;
case 2:
wm8350->pmic.max_dcdc = WM8350_DCDC_6;
wm8350->pmic.max_isink = WM8350_ISINK_B;
switch (chip_rev) {
case 0:
dev_info(wm8350->dev, "WM8352 Rev A\n");
wm8350->power.rev_g_coeff = 1;
break;
default:
dev_err(wm8350->dev, "Unknown WM8352 CHIP_REV\n");
ret = -ENODEV;
goto err;
}
break;
default:
dev_err(wm8350->dev, "Unknown MASK_REV\n");
ret = -ENODEV;
goto err;
}
ret = wm8350_create_cache(wm8350, mask_rev, mode);
if (ret < 0) {
dev_err(wm8350->dev, "Failed to create register cache\n");
return ret;
}
mutex_init(&wm8350->auxadc_mutex);
init_completion(&wm8350->auxadc_done);
ret = wm8350_irq_init(wm8350, irq, pdata);
if (ret < 0)
goto err;
if (wm8350->irq_base) {
ret = request_threaded_irq(wm8350->irq_base +
WM8350_IRQ_AUXADC_DATARDY,
NULL, wm8350_auxadc_irq, 0,
"auxadc", wm8350);
if (ret < 0)
dev_warn(wm8350->dev,
"Failed to request AUXADC IRQ: %d\n", ret);
}
if (pdata && pdata->init) {
ret = pdata->init(wm8350);
if (ret != 0) {
dev_err(wm8350->dev, "Platform init() failed: %d\n",
ret);
goto err_irq;
}
}
wm8350_reg_write(wm8350, WM8350_SYSTEM_INTERRUPTS_MASK, 0x0);
wm8350_client_dev_register(wm8350, "wm8350-codec",
&(wm8350->codec.pdev));
wm8350_client_dev_register(wm8350, "wm8350-gpio",
&(wm8350->gpio.pdev));
wm8350_client_dev_register(wm8350, "wm8350-hwmon",
&(wm8350->hwmon.pdev));
wm8350_client_dev_register(wm8350, "wm8350-power",
&(wm8350->power.pdev));
wm8350_client_dev_register(wm8350, "wm8350-rtc", &(wm8350->rtc.pdev));
wm8350_client_dev_register(wm8350, "wm8350-wdt", &(wm8350->wdt.pdev));
return 0;
err_irq:
wm8350_irq_exit(wm8350);
err:
kfree(wm8350->reg_cache);
return ret;
}
EXPORT_SYMBOL_GPL(wm8350_device_init);
void wm8350_device_exit(struct wm8350 *wm8350)
{
int i;
for (i = 0; i < ARRAY_SIZE(wm8350->pmic.led); i++)
platform_device_unregister(wm8350->pmic.led[i].pdev);
for (i = 0; i < ARRAY_SIZE(wm8350->pmic.pdev); i++)
platform_device_unregister(wm8350->pmic.pdev[i]);
platform_device_unregister(wm8350->wdt.pdev);
platform_device_unregister(wm8350->rtc.pdev);
platform_device_unregister(wm8350->power.pdev);
platform_device_unregister(wm8350->hwmon.pdev);
platform_device_unregister(wm8350->gpio.pdev);
platform_device_unregister(wm8350->codec.pdev);
if (wm8350->irq_base)
free_irq(wm8350->irq_base + WM8350_IRQ_AUXADC_DATARDY, wm8350);
wm8350_irq_exit(wm8350);
kfree(wm8350->reg_cache);
}
EXPORT_SYMBOL_GPL(wm8350_device_exit);
MODULE_DESCRIPTION("WM8350 AudioPlus PMIC core driver");
MODULE_LICENSE("GPL");