329 lines
8.6 KiB
C
329 lines
8.6 KiB
C
/*
|
|
* Copyright (c) 2016 MediaTek Inc.
|
|
* Author: Zhiyong Tao <zhiyong.tao@mediatek.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#include <linux/clk.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/err.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/iopoll.h>
|
|
#include <linux/io.h>
|
|
#include <linux/iio/iio.h>
|
|
|
|
/* Register definitions */
|
|
#define MT6577_AUXADC_CON0 0x00
|
|
#define MT6577_AUXADC_CON1 0x04
|
|
#define MT6577_AUXADC_CON2 0x10
|
|
#define MT6577_AUXADC_STA BIT(0)
|
|
|
|
#define MT6577_AUXADC_DAT0 0x14
|
|
#define MT6577_AUXADC_RDY0 BIT(12)
|
|
|
|
#define MT6577_AUXADC_MISC 0x94
|
|
#define MT6577_AUXADC_PDN_EN BIT(14)
|
|
|
|
#define MT6577_AUXADC_DAT_MASK 0xfff
|
|
#define MT6577_AUXADC_SLEEP_US 1000
|
|
#define MT6577_AUXADC_TIMEOUT_US 10000
|
|
#define MT6577_AUXADC_POWER_READY_MS 1
|
|
#define MT6577_AUXADC_SAMPLE_READY_US 25
|
|
|
|
struct mt6577_auxadc_device {
|
|
void __iomem *reg_base;
|
|
struct clk *adc_clk;
|
|
struct mutex lock;
|
|
};
|
|
|
|
#define MT6577_AUXADC_CHANNEL(idx) { \
|
|
.type = IIO_VOLTAGE, \
|
|
.indexed = 1, \
|
|
.channel = (idx), \
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \
|
|
}
|
|
|
|
static const struct iio_chan_spec mt6577_auxadc_iio_channels[] = {
|
|
MT6577_AUXADC_CHANNEL(0),
|
|
MT6577_AUXADC_CHANNEL(1),
|
|
MT6577_AUXADC_CHANNEL(2),
|
|
MT6577_AUXADC_CHANNEL(3),
|
|
MT6577_AUXADC_CHANNEL(4),
|
|
MT6577_AUXADC_CHANNEL(5),
|
|
MT6577_AUXADC_CHANNEL(6),
|
|
MT6577_AUXADC_CHANNEL(7),
|
|
MT6577_AUXADC_CHANNEL(8),
|
|
MT6577_AUXADC_CHANNEL(9),
|
|
MT6577_AUXADC_CHANNEL(10),
|
|
MT6577_AUXADC_CHANNEL(11),
|
|
MT6577_AUXADC_CHANNEL(12),
|
|
MT6577_AUXADC_CHANNEL(13),
|
|
MT6577_AUXADC_CHANNEL(14),
|
|
MT6577_AUXADC_CHANNEL(15),
|
|
};
|
|
|
|
static inline void mt6577_auxadc_mod_reg(void __iomem *reg,
|
|
u32 or_mask, u32 and_mask)
|
|
{
|
|
u32 val;
|
|
|
|
val = readl(reg);
|
|
val |= or_mask;
|
|
val &= ~and_mask;
|
|
writel(val, reg);
|
|
}
|
|
|
|
static int mt6577_auxadc_read(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan)
|
|
{
|
|
u32 val;
|
|
void __iomem *reg_channel;
|
|
int ret;
|
|
struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
|
|
|
|
reg_channel = adc_dev->reg_base + MT6577_AUXADC_DAT0 +
|
|
chan->channel * 0x04;
|
|
|
|
mutex_lock(&adc_dev->lock);
|
|
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_CON1,
|
|
0, 1 << chan->channel);
|
|
|
|
/* read channel and make sure old ready bit == 0 */
|
|
ret = readl_poll_timeout(reg_channel, val,
|
|
((val & MT6577_AUXADC_RDY0) == 0),
|
|
MT6577_AUXADC_SLEEP_US,
|
|
MT6577_AUXADC_TIMEOUT_US);
|
|
if (ret < 0) {
|
|
dev_err(indio_dev->dev.parent,
|
|
"wait for channel[%d] ready bit clear time out\n",
|
|
chan->channel);
|
|
goto err_timeout;
|
|
}
|
|
|
|
/* set bit to trigger sample */
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_CON1,
|
|
1 << chan->channel, 0);
|
|
|
|
/* we must delay here for hardware sample channel data */
|
|
udelay(MT6577_AUXADC_SAMPLE_READY_US);
|
|
|
|
/* check MTK_AUXADC_CON2 if auxadc is idle */
|
|
ret = readl_poll_timeout(adc_dev->reg_base + MT6577_AUXADC_CON2, val,
|
|
((val & MT6577_AUXADC_STA) == 0),
|
|
MT6577_AUXADC_SLEEP_US,
|
|
MT6577_AUXADC_TIMEOUT_US);
|
|
if (ret < 0) {
|
|
dev_err(indio_dev->dev.parent,
|
|
"wait for auxadc idle time out\n");
|
|
goto err_timeout;
|
|
}
|
|
|
|
/* read channel and make sure ready bit == 1 */
|
|
ret = readl_poll_timeout(reg_channel, val,
|
|
((val & MT6577_AUXADC_RDY0) != 0),
|
|
MT6577_AUXADC_SLEEP_US,
|
|
MT6577_AUXADC_TIMEOUT_US);
|
|
if (ret < 0) {
|
|
dev_err(indio_dev->dev.parent,
|
|
"wait for channel[%d] data ready time out\n",
|
|
chan->channel);
|
|
goto err_timeout;
|
|
}
|
|
|
|
/* read data */
|
|
val = readl(reg_channel) & MT6577_AUXADC_DAT_MASK;
|
|
|
|
mutex_unlock(&adc_dev->lock);
|
|
|
|
return val;
|
|
|
|
err_timeout:
|
|
|
|
mutex_unlock(&adc_dev->lock);
|
|
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
static int mt6577_auxadc_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val,
|
|
int *val2,
|
|
long info)
|
|
{
|
|
switch (info) {
|
|
case IIO_CHAN_INFO_PROCESSED:
|
|
*val = mt6577_auxadc_read(indio_dev, chan);
|
|
if (*val < 0) {
|
|
dev_err(indio_dev->dev.parent,
|
|
"failed to sample data on channel[%d]\n",
|
|
chan->channel);
|
|
return *val;
|
|
}
|
|
return IIO_VAL_INT;
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static const struct iio_info mt6577_auxadc_info = {
|
|
.read_raw = &mt6577_auxadc_read_raw,
|
|
};
|
|
|
|
static int __maybe_unused mt6577_auxadc_resume(struct device *dev)
|
|
{
|
|
struct iio_dev *indio_dev = dev_get_drvdata(dev);
|
|
struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
ret = clk_prepare_enable(adc_dev->adc_clk);
|
|
if (ret) {
|
|
pr_err("failed to enable auxadc clock\n");
|
|
return ret;
|
|
}
|
|
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
|
|
MT6577_AUXADC_PDN_EN, 0);
|
|
mdelay(MT6577_AUXADC_POWER_READY_MS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused mt6577_auxadc_suspend(struct device *dev)
|
|
{
|
|
struct iio_dev *indio_dev = dev_get_drvdata(dev);
|
|
struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
|
|
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
|
|
0, MT6577_AUXADC_PDN_EN);
|
|
clk_disable_unprepare(adc_dev->adc_clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mt6577_auxadc_probe(struct platform_device *pdev)
|
|
{
|
|
struct mt6577_auxadc_device *adc_dev;
|
|
unsigned long adc_clk_rate;
|
|
struct resource *res;
|
|
struct iio_dev *indio_dev;
|
|
int ret;
|
|
|
|
indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc_dev));
|
|
if (!indio_dev)
|
|
return -ENOMEM;
|
|
|
|
adc_dev = iio_priv(indio_dev);
|
|
indio_dev->dev.parent = &pdev->dev;
|
|
indio_dev->name = dev_name(&pdev->dev);
|
|
indio_dev->info = &mt6577_auxadc_info;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->channels = mt6577_auxadc_iio_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(mt6577_auxadc_iio_channels);
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
adc_dev->reg_base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(adc_dev->reg_base)) {
|
|
dev_err(&pdev->dev, "failed to get auxadc base address\n");
|
|
return PTR_ERR(adc_dev->reg_base);
|
|
}
|
|
|
|
adc_dev->adc_clk = devm_clk_get(&pdev->dev, "main");
|
|
if (IS_ERR(adc_dev->adc_clk)) {
|
|
dev_err(&pdev->dev, "failed to get auxadc clock\n");
|
|
return PTR_ERR(adc_dev->adc_clk);
|
|
}
|
|
|
|
ret = clk_prepare_enable(adc_dev->adc_clk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to enable auxadc clock\n");
|
|
return ret;
|
|
}
|
|
|
|
adc_clk_rate = clk_get_rate(adc_dev->adc_clk);
|
|
if (!adc_clk_rate) {
|
|
ret = -EINVAL;
|
|
dev_err(&pdev->dev, "null clock rate\n");
|
|
goto err_disable_clk;
|
|
}
|
|
|
|
mutex_init(&adc_dev->lock);
|
|
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
|
|
MT6577_AUXADC_PDN_EN, 0);
|
|
mdelay(MT6577_AUXADC_POWER_READY_MS);
|
|
|
|
platform_set_drvdata(pdev, indio_dev);
|
|
|
|
ret = iio_device_register(indio_dev);
|
|
if (ret < 0) {
|
|
dev_err(&pdev->dev, "failed to register iio device\n");
|
|
goto err_power_off;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_power_off:
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
|
|
0, MT6577_AUXADC_PDN_EN);
|
|
err_disable_clk:
|
|
clk_disable_unprepare(adc_dev->adc_clk);
|
|
return ret;
|
|
}
|
|
|
|
static int mt6577_auxadc_remove(struct platform_device *pdev)
|
|
{
|
|
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
|
|
struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev);
|
|
|
|
iio_device_unregister(indio_dev);
|
|
|
|
mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC,
|
|
0, MT6577_AUXADC_PDN_EN);
|
|
|
|
clk_disable_unprepare(adc_dev->adc_clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(mt6577_auxadc_pm_ops,
|
|
mt6577_auxadc_suspend,
|
|
mt6577_auxadc_resume);
|
|
|
|
static const struct of_device_id mt6577_auxadc_of_match[] = {
|
|
{ .compatible = "mediatek,mt2701-auxadc", },
|
|
{ .compatible = "mediatek,mt2712-auxadc", },
|
|
{ .compatible = "mediatek,mt7622-auxadc", },
|
|
{ .compatible = "mediatek,mt8173-auxadc", },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, mt6577_auxadc_of_match);
|
|
|
|
static struct platform_driver mt6577_auxadc_driver = {
|
|
.driver = {
|
|
.name = "mt6577-auxadc",
|
|
.of_match_table = mt6577_auxadc_of_match,
|
|
.pm = &mt6577_auxadc_pm_ops,
|
|
},
|
|
.probe = mt6577_auxadc_probe,
|
|
.remove = mt6577_auxadc_remove,
|
|
};
|
|
module_platform_driver(mt6577_auxadc_driver);
|
|
|
|
MODULE_AUTHOR("Zhiyong Tao <zhiyong.tao@mediatek.com>");
|
|
MODULE_DESCRIPTION("MTK AUXADC Device Driver");
|
|
MODULE_LICENSE("GPL v2");
|