linux-imx

/*

 * 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;