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linux-stable/drivers/iio/adc/ingenic-adc.c
Christophe Branchereau bf1b2418c2 iio/adc: ingenic: add JZ4760B support to the sadc driver 
The JZ4760B variant differs slightly from the JZ4760: it has a bit called VBAT_SEL in the CFG register.

In order to correctly sample the battery voltage on existing handhelds using this SOC, the bit must be cleared.

We leave the possibility to set the bit, by using the "ingenic,use-internal-divider" in the devicetree.

Signed-off-by: Christophe Branchereau <cbranchereau@gmail.com>
Link: https://lore.kernel.org/r/20210726082033.351533-5-cbranchereau@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-07-31 18:14:53 +01:00

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// SPDX-License-Identifier: GPL-2.0
/*
* ADC driver for the Ingenic JZ47xx SoCs
* Copyright (c) 2019 Artur Rojek <contact@artur-rojek.eu>
*
* based on drivers/mfd/jz4740-adc.c
*/
#include <dt-bindings/iio/adc/ingenic,adc.h>
#include <linux/clk.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#define JZ_ADC_REG_ENABLE 0x00
#define JZ_ADC_REG_CFG 0x04
#define JZ_ADC_REG_CTRL 0x08
#define JZ_ADC_REG_STATUS 0x0c
#define JZ_ADC_REG_ADSAME 0x10
#define JZ_ADC_REG_ADWAIT 0x14
#define JZ_ADC_REG_ADTCH 0x18
#define JZ_ADC_REG_ADBDAT 0x1c
#define JZ_ADC_REG_ADSDAT 0x20
#define JZ_ADC_REG_ADCMD 0x24
#define JZ_ADC_REG_ADCLK 0x28
#define JZ_ADC_REG_ENABLE_PD BIT(7)
#define JZ_ADC_REG_CFG_AUX_MD (BIT(0) | BIT(1))
#define JZ_ADC_REG_CFG_BAT_MD BIT(4)
#define JZ_ADC_REG_CFG_SAMPLE_NUM(n) ((n) << 10)
#define JZ_ADC_REG_CFG_PULL_UP(n) ((n) << 16)
#define JZ_ADC_REG_CFG_CMD_SEL BIT(22)
#define JZ_ADC_REG_CFG_VBAT_SEL BIT(30)
#define JZ_ADC_REG_CFG_TOUCH_OPS_MASK (BIT(31) | GENMASK(23, 10))
#define JZ_ADC_REG_ADCLK_CLKDIV_LSB 0
#define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB 16
#define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB 8
#define JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB 16
#define JZ_ADC_REG_ADCMD_YNADC BIT(7)
#define JZ_ADC_REG_ADCMD_YPADC BIT(8)
#define JZ_ADC_REG_ADCMD_XNADC BIT(9)
#define JZ_ADC_REG_ADCMD_XPADC BIT(10)
#define JZ_ADC_REG_ADCMD_VREFPYP BIT(11)
#define JZ_ADC_REG_ADCMD_VREFPXP BIT(12)
#define JZ_ADC_REG_ADCMD_VREFPXN BIT(13)
#define JZ_ADC_REG_ADCMD_VREFPAUX BIT(14)
#define JZ_ADC_REG_ADCMD_VREFPVDD33 BIT(15)
#define JZ_ADC_REG_ADCMD_VREFNYN BIT(16)
#define JZ_ADC_REG_ADCMD_VREFNXP BIT(17)
#define JZ_ADC_REG_ADCMD_VREFNXN BIT(18)
#define JZ_ADC_REG_ADCMD_VREFAUX BIT(19)
#define JZ_ADC_REG_ADCMD_YNGRU BIT(20)
#define JZ_ADC_REG_ADCMD_XNGRU BIT(21)
#define JZ_ADC_REG_ADCMD_XPGRU BIT(22)
#define JZ_ADC_REG_ADCMD_YPSUP BIT(23)
#define JZ_ADC_REG_ADCMD_XNSUP BIT(24)
#define JZ_ADC_REG_ADCMD_XPSUP BIT(25)
#define JZ_ADC_AUX_VREF 3300
#define JZ_ADC_AUX_VREF_BITS 12
#define JZ_ADC_BATTERY_LOW_VREF 2500
#define JZ_ADC_BATTERY_LOW_VREF_BITS 12
#define JZ4725B_ADC_BATTERY_HIGH_VREF 7500
#define JZ4725B_ADC_BATTERY_HIGH_VREF_BITS 10
#define JZ4740_ADC_BATTERY_HIGH_VREF (7500 * 0.986)
#define JZ4740_ADC_BATTERY_HIGH_VREF_BITS 12
#define JZ4760_ADC_BATTERY_VREF 2500
#define JZ4770_ADC_BATTERY_VREF 1200
#define JZ4770_ADC_BATTERY_VREF_BITS 12
#define JZ_ADC_IRQ_AUX BIT(0)
#define JZ_ADC_IRQ_BATTERY BIT(1)
#define JZ_ADC_IRQ_TOUCH BIT(2)
#define JZ_ADC_IRQ_PEN_DOWN BIT(3)
#define JZ_ADC_IRQ_PEN_UP BIT(4)
#define JZ_ADC_IRQ_PEN_DOWN_SLEEP BIT(5)
#define JZ_ADC_IRQ_SLEEP BIT(7)
struct ingenic_adc;
struct ingenic_adc_soc_data {
unsigned int battery_high_vref;
unsigned int battery_high_vref_bits;
const int *battery_raw_avail;
size_t battery_raw_avail_size;
const int *battery_scale_avail;
size_t battery_scale_avail_size;
unsigned int battery_vref_mode: 1;
unsigned int has_aux_md: 1;
const struct iio_chan_spec *channels;
unsigned int num_channels;
int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc);
};
struct ingenic_adc {
void __iomem *base;
struct clk *clk;
struct mutex lock;
struct mutex aux_lock;
const struct ingenic_adc_soc_data *soc_data;
bool low_vref_mode;
};
static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, unsigned long mask)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
mutex_lock(&adc->lock);
/* Init ADCMD */
readl(adc->base + JZ_ADC_REG_ADCMD);
if (mask & 0x3) {
/* Second channel (INGENIC_ADC_TOUCH_YP): sample YP vs. GND */
writel(JZ_ADC_REG_ADCMD_XNGRU
| JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
| JZ_ADC_REG_ADCMD_YPADC,
adc->base + JZ_ADC_REG_ADCMD);
/* First channel (INGENIC_ADC_TOUCH_XP): sample XP vs. GND */
writel(JZ_ADC_REG_ADCMD_YNGRU
| JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
| JZ_ADC_REG_ADCMD_XPADC,
adc->base + JZ_ADC_REG_ADCMD);
}
if (mask & 0xc) {
/* Fourth channel (INGENIC_ADC_TOUCH_YN): sample YN vs. GND */
writel(JZ_ADC_REG_ADCMD_XNGRU
| JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
| JZ_ADC_REG_ADCMD_YNADC,
adc->base + JZ_ADC_REG_ADCMD);
/* Third channel (INGENIC_ADC_TOUCH_XN): sample XN vs. GND */
writel(JZ_ADC_REG_ADCMD_YNGRU
| JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
| JZ_ADC_REG_ADCMD_XNADC,
adc->base + JZ_ADC_REG_ADCMD);
}
if (mask & 0x30) {
/* Sixth channel (INGENIC_ADC_TOUCH_YD): sample YP vs. YN */
writel(JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
| JZ_ADC_REG_ADCMD_YPADC,
adc->base + JZ_ADC_REG_ADCMD);
/* Fifth channel (INGENIC_ADC_TOUCH_XD): sample XP vs. XN */
writel(JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
| JZ_ADC_REG_ADCMD_XPADC,
adc->base + JZ_ADC_REG_ADCMD);
}
/* We're done */
writel(0, adc->base + JZ_ADC_REG_ADCMD);
mutex_unlock(&adc->lock);
}
static void ingenic_adc_set_config(struct ingenic_adc *adc,
uint32_t mask,
uint32_t val)
{
uint32_t cfg;
mutex_lock(&adc->lock);
cfg = readl(adc->base + JZ_ADC_REG_CFG) & ~mask;
cfg |= val;
writel(cfg, adc->base + JZ_ADC_REG_CFG);
mutex_unlock(&adc->lock);
}
static void ingenic_adc_enable_unlocked(struct ingenic_adc *adc,
int engine,
bool enabled)
{
u8 val;
val = readb(adc->base + JZ_ADC_REG_ENABLE);
if (enabled)
val |= BIT(engine);
else
val &= ~BIT(engine);
writeb(val, adc->base + JZ_ADC_REG_ENABLE);
}
static void ingenic_adc_enable(struct ingenic_adc *adc,
int engine,
bool enabled)
{
mutex_lock(&adc->lock);
ingenic_adc_enable_unlocked(adc, engine, enabled);
mutex_unlock(&adc->lock);
}
static int ingenic_adc_capture(struct ingenic_adc *adc,
int engine)
{
u32 cfg;
u8 val;
int ret;
/*
* Disable CMD_SEL temporarily, because it causes wrong VBAT readings,
* probably due to the switch of VREF. We must keep the lock here to
* avoid races with the buffer enable/disable functions.
*/
mutex_lock(&adc->lock);
cfg = readl(adc->base + JZ_ADC_REG_CFG);
writel(cfg & ~JZ_ADC_REG_CFG_CMD_SEL, adc->base + JZ_ADC_REG_CFG);
ingenic_adc_enable_unlocked(adc, engine, true);
ret = readb_poll_timeout(adc->base + JZ_ADC_REG_ENABLE, val,
!(val & BIT(engine)), 250, 1000);
if (ret)
ingenic_adc_enable_unlocked(adc, engine, false);
writel(cfg, adc->base + JZ_ADC_REG_CFG);
mutex_unlock(&adc->lock);
return ret;
}
static int ingenic_adc_write_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long m)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
struct device *dev = iio_dev->dev.parent;
int ret;
switch (m) {
case IIO_CHAN_INFO_SCALE:
switch (chan->channel) {
case INGENIC_ADC_BATTERY:
if (!adc->soc_data->battery_vref_mode)
return -EINVAL;
ret = clk_enable(adc->clk);
if (ret) {
dev_err(dev, "Failed to enable clock: %d\n",
ret);
return ret;
}
if (val > JZ_ADC_BATTERY_LOW_VREF) {
ingenic_adc_set_config(adc,
JZ_ADC_REG_CFG_BAT_MD,
0);
adc->low_vref_mode = false;
} else {
ingenic_adc_set_config(adc,
JZ_ADC_REG_CFG_BAT_MD,
JZ_ADC_REG_CFG_BAT_MD);
adc->low_vref_mode = true;
}
clk_disable(adc->clk);
return 0;
default:
return -EINVAL;
}
default:
return -EINVAL;
}
}
static const int jz4725b_adc_battery_raw_avail[] = {
0, 1, (1 << JZ_ADC_BATTERY_LOW_VREF_BITS) - 1,
};
static const int jz4725b_adc_battery_scale_avail[] = {
JZ4725B_ADC_BATTERY_HIGH_VREF, JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_VREF_BITS,
};
static const int jz4740_adc_battery_raw_avail[] = {
0, 1, (1 << JZ_ADC_BATTERY_LOW_VREF_BITS) - 1,
};
static const int jz4740_adc_battery_scale_avail[] = {
JZ4740_ADC_BATTERY_HIGH_VREF, JZ4740_ADC_BATTERY_HIGH_VREF_BITS,
JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_VREF_BITS,
};
static const int jz4760_adc_battery_scale_avail[] = {
JZ4760_ADC_BATTERY_VREF, JZ4770_ADC_BATTERY_VREF_BITS,
};
static const int jz4770_adc_battery_raw_avail[] = {
0, 1, (1 << JZ4770_ADC_BATTERY_VREF_BITS) - 1,
};
static const int jz4770_adc_battery_scale_avail[] = {
JZ4770_ADC_BATTERY_VREF, JZ4770_ADC_BATTERY_VREF_BITS,
};
static int jz4725b_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
{
struct clk *parent_clk;
unsigned long parent_rate, rate;
unsigned int div_main, div_10us;
parent_clk = clk_get_parent(adc->clk);
if (!parent_clk) {
dev_err(dev, "ADC clock has no parent\n");
return -ENODEV;
}
parent_rate = clk_get_rate(parent_clk);
/*
* The JZ4725B ADC works at 500 kHz to 8 MHz.
* We pick the highest rate possible.
* In practice we typically get 6 MHz, half of the 12 MHz EXT clock.
*/
div_main = DIV_ROUND_UP(parent_rate, 8000000);
div_main = clamp(div_main, 1u, 64u);
rate = parent_rate / div_main;
if (rate < 500000 || rate > 8000000) {
dev_err(dev, "No valid divider for ADC main clock\n");
return -EINVAL;
}
/* We also need a divider that produces a 10us clock. */
div_10us = DIV_ROUND_UP(rate, 100000);
writel(((div_10us - 1) << JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB) |
(div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB,
adc->base + JZ_ADC_REG_ADCLK);
return 0;
}
static int jz4770_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
{
struct clk *parent_clk;
unsigned long parent_rate, rate;
unsigned int div_main, div_ms, div_10us;
parent_clk = clk_get_parent(adc->clk);
if (!parent_clk) {
dev_err(dev, "ADC clock has no parent\n");
return -ENODEV;
}
parent_rate = clk_get_rate(parent_clk);
/*
* The JZ4770 ADC works at 20 kHz to 200 kHz.
* We pick the highest rate possible.
*/
div_main = DIV_ROUND_UP(parent_rate, 200000);
div_main = clamp(div_main, 1u, 256u);
rate = parent_rate / div_main;
if (rate < 20000 || rate > 200000) {
dev_err(dev, "No valid divider for ADC main clock\n");
return -EINVAL;
}
/* We also need a divider that produces a 10us clock. */
div_10us = DIV_ROUND_UP(rate, 10000);
/* And another, which produces a 1ms clock. */
div_ms = DIV_ROUND_UP(rate, 1000);
writel(((div_ms - 1) << JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB) |
((div_10us - 1) << JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB) |
(div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB,
adc->base + JZ_ADC_REG_ADCLK);
return 0;
}
static const struct iio_chan_spec jz4740_channels[] = {
{
.extend_name = "aux",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_AUX,
.scan_index = -1,
},
{
.extend_name = "battery",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_BATTERY,
.scan_index = -1,
},
};
static const struct iio_chan_spec jz4760_channels[] = {
{
.extend_name = "aux",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_AUX0,
.scan_index = -1,
},
{
.extend_name = "aux1",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_AUX,
.scan_index = -1,
},
{
.extend_name = "aux2",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_AUX2,
.scan_index = -1,
},
{
.extend_name = "battery",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_BATTERY,
.scan_index = -1,
},
};
static const struct iio_chan_spec jz4770_channels[] = {
{
.type = IIO_VOLTAGE,
.indexed = 1,
.channel = INGENIC_ADC_TOUCH_XP,
.scan_index = 0,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
},
},
{
.type = IIO_VOLTAGE,
.indexed = 1,
.channel = INGENIC_ADC_TOUCH_YP,
.scan_index = 1,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
},
},
{
.type = IIO_VOLTAGE,
.indexed = 1,
.channel = INGENIC_ADC_TOUCH_XN,
.scan_index = 2,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
},
},
{
.type = IIO_VOLTAGE,
.indexed = 1,
.channel = INGENIC_ADC_TOUCH_YN,
.scan_index = 3,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
},
},
{
.type = IIO_VOLTAGE,
.indexed = 1,
.channel = INGENIC_ADC_TOUCH_XD,
.scan_index = 4,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
},
},
{
.type = IIO_VOLTAGE,
.indexed = 1,
.channel = INGENIC_ADC_TOUCH_YD,
.scan_index = 5,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
},
},
{
.extend_name = "aux",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_AUX,
.scan_index = -1,
},
{
.extend_name = "battery",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_BATTERY,
.scan_index = -1,
},
{
.extend_name = "aux2",
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.indexed = 1,
.channel = INGENIC_ADC_AUX2,
.scan_index = -1,
},
};
static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
.battery_high_vref = JZ4725B_ADC_BATTERY_HIGH_VREF,
.battery_high_vref_bits = JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
.battery_raw_avail = jz4725b_adc_battery_raw_avail,
.battery_raw_avail_size = ARRAY_SIZE(jz4725b_adc_battery_raw_avail),
.battery_scale_avail = jz4725b_adc_battery_scale_avail,
.battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail),
.battery_vref_mode = true,
.has_aux_md = false,
.channels = jz4740_channels,
.num_channels = ARRAY_SIZE(jz4740_channels),
.init_clk_div = jz4725b_adc_init_clk_div,
};
static const struct ingenic_adc_soc_data jz4740_adc_soc_data = {
.battery_high_vref = JZ4740_ADC_BATTERY_HIGH_VREF,
.battery_high_vref_bits = JZ4740_ADC_BATTERY_HIGH_VREF_BITS,
.battery_raw_avail = jz4740_adc_battery_raw_avail,
.battery_raw_avail_size = ARRAY_SIZE(jz4740_adc_battery_raw_avail),
.battery_scale_avail = jz4740_adc_battery_scale_avail,
.battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail),
.battery_vref_mode = true,
.has_aux_md = false,
.channels = jz4740_channels,
.num_channels = ARRAY_SIZE(jz4740_channels),
.init_clk_div = NULL, /* no ADCLK register on JZ4740 */
};
static const struct ingenic_adc_soc_data jz4760_adc_soc_data = {
.battery_high_vref = JZ4760_ADC_BATTERY_VREF,
.battery_high_vref_bits = JZ4770_ADC_BATTERY_VREF_BITS,
.battery_raw_avail = jz4770_adc_battery_raw_avail,
.battery_raw_avail_size = ARRAY_SIZE(jz4770_adc_battery_raw_avail),
.battery_scale_avail = jz4760_adc_battery_scale_avail,
.battery_scale_avail_size = ARRAY_SIZE(jz4760_adc_battery_scale_avail),
.battery_vref_mode = false,
.has_aux_md = true,
.channels = jz4760_channels,
.num_channels = ARRAY_SIZE(jz4760_channels),
.init_clk_div = jz4770_adc_init_clk_div,
};
static const struct ingenic_adc_soc_data jz4770_adc_soc_data = {
.battery_high_vref = JZ4770_ADC_BATTERY_VREF,
.battery_high_vref_bits = JZ4770_ADC_BATTERY_VREF_BITS,
.battery_raw_avail = jz4770_adc_battery_raw_avail,
.battery_raw_avail_size = ARRAY_SIZE(jz4770_adc_battery_raw_avail),
.battery_scale_avail = jz4770_adc_battery_scale_avail,
.battery_scale_avail_size = ARRAY_SIZE(jz4770_adc_battery_scale_avail),
.battery_vref_mode = false,
.has_aux_md = true,
.channels = jz4770_channels,
.num_channels = ARRAY_SIZE(jz4770_channels),
.init_clk_div = jz4770_adc_init_clk_div,
};
static int ingenic_adc_read_avail(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan,
const int **vals,
int *type,
int *length,
long m)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
switch (m) {
case IIO_CHAN_INFO_RAW:
*type = IIO_VAL_INT;
*length = adc->soc_data->battery_raw_avail_size;
*vals = adc->soc_data->battery_raw_avail;
return IIO_AVAIL_RANGE;
case IIO_CHAN_INFO_SCALE:
*type = IIO_VAL_FRACTIONAL_LOG2;
*length = adc->soc_data->battery_scale_avail_size;
*vals = adc->soc_data->battery_scale_avail;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static int ingenic_adc_read_chan_info_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan,
int *val)
{
int cmd, ret, engine = (chan->channel == INGENIC_ADC_BATTERY);
struct ingenic_adc *adc = iio_priv(iio_dev);
ret = clk_enable(adc->clk);
if (ret) {
dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
ret);
return ret;
}
/* We cannot sample the aux channels in parallel. */
mutex_lock(&adc->aux_lock);
if (adc->soc_data->has_aux_md && engine == 0) {
switch (chan->channel) {
case INGENIC_ADC_AUX0:
cmd = 0;
break;
case INGENIC_ADC_AUX:
cmd = 1;
break;
case INGENIC_ADC_AUX2:
cmd = 2;
break;
}
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, cmd);
}
ret = ingenic_adc_capture(adc, engine);
if (ret)
goto out;
switch (chan->channel) {
case INGENIC_ADC_AUX0:
case INGENIC_ADC_AUX:
case INGENIC_ADC_AUX2:
*val = readw(adc->base + JZ_ADC_REG_ADSDAT);
break;
case INGENIC_ADC_BATTERY:
*val = readw(adc->base + JZ_ADC_REG_ADBDAT);
break;
}
ret = IIO_VAL_INT;
out:
mutex_unlock(&adc->aux_lock);
clk_disable(adc->clk);
return ret;
}
static int ingenic_adc_read_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
switch (m) {
case IIO_CHAN_INFO_RAW:
return ingenic_adc_read_chan_info_raw(iio_dev, chan, val);
case IIO_CHAN_INFO_SCALE:
switch (chan->channel) {
case INGENIC_ADC_AUX0:
case INGENIC_ADC_AUX:
case INGENIC_ADC_AUX2:
*val = JZ_ADC_AUX_VREF;
*val2 = JZ_ADC_AUX_VREF_BITS;
break;
case INGENIC_ADC_BATTERY:
if (adc->low_vref_mode) {
*val = JZ_ADC_BATTERY_LOW_VREF;
*val2 = JZ_ADC_BATTERY_LOW_VREF_BITS;
} else {
*val = adc->soc_data->battery_high_vref;
*val2 = adc->soc_data->battery_high_vref_bits;
}
break;
}
return IIO_VAL_FRACTIONAL_LOG2;
default:
return -EINVAL;
}
}
static int ingenic_adc_of_xlate(struct iio_dev *iio_dev,
const struct of_phandle_args *iiospec)
{
int i;
if (!iiospec->args_count)
return -EINVAL;
for (i = 0; i < iio_dev->num_channels; ++i)
if (iio_dev->channels[i].channel == iiospec->args[0])
return i;
return -EINVAL;
}
static void ingenic_adc_clk_cleanup(void *data)
{
clk_unprepare(data);
}
static const struct iio_info ingenic_adc_info = {
.write_raw = ingenic_adc_write_raw,
.read_raw = ingenic_adc_read_raw,
.read_avail = ingenic_adc_read_avail,
.of_xlate = ingenic_adc_of_xlate,
};
static int ingenic_adc_buffer_enable(struct iio_dev *iio_dev)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
int ret;
ret = clk_enable(adc->clk);
if (ret) {
dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
ret);
return ret;
}
/* It takes significant time for the touchscreen hw to stabilize. */
msleep(50);
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK,
JZ_ADC_REG_CFG_SAMPLE_NUM(4) |
JZ_ADC_REG_CFG_PULL_UP(4));
writew(80, adc->base + JZ_ADC_REG_ADWAIT);
writew(2, adc->base + JZ_ADC_REG_ADSAME);
writeb((u8)~JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_CTRL);
writel(0, adc->base + JZ_ADC_REG_ADTCH);
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL,
JZ_ADC_REG_CFG_CMD_SEL);
ingenic_adc_set_adcmd(iio_dev, iio_dev->active_scan_mask[0]);
ingenic_adc_enable(adc, 2, true);
return 0;
}
static int ingenic_adc_buffer_disable(struct iio_dev *iio_dev)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
ingenic_adc_enable(adc, 2, false);
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL, 0);
writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
writeb(0xff, adc->base + JZ_ADC_REG_STATUS);
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, 0);
writew(0, adc->base + JZ_ADC_REG_ADSAME);
writew(0, adc->base + JZ_ADC_REG_ADWAIT);
clk_disable(adc->clk);
return 0;
}
static const struct iio_buffer_setup_ops ingenic_buffer_setup_ops = {
.postenable = &ingenic_adc_buffer_enable,
.predisable = &ingenic_adc_buffer_disable
};
static irqreturn_t ingenic_adc_irq(int irq, void *data)
{
struct iio_dev *iio_dev = data;
struct ingenic_adc *adc = iio_priv(iio_dev);
unsigned long mask = iio_dev->active_scan_mask[0];
unsigned int i;
u32 tdat[3];
for (i = 0; i < ARRAY_SIZE(tdat); mask >>= 2, i++) {
if (mask & 0x3)
tdat[i] = readl(adc->base + JZ_ADC_REG_ADTCH);
else
tdat[i] = 0;
}
iio_push_to_buffers(iio_dev, tdat);
writeb(JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_STATUS);
return IRQ_HANDLED;
}
static int ingenic_adc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct iio_dev *iio_dev;
struct ingenic_adc *adc;
const struct ingenic_adc_soc_data *soc_data;
int irq, ret;
soc_data = device_get_match_data(dev);
if (!soc_data)
return -EINVAL;
iio_dev = devm_iio_device_alloc(dev, sizeof(*adc));
if (!iio_dev)
return -ENOMEM;
adc = iio_priv(iio_dev);
mutex_init(&adc->lock);
mutex_init(&adc->aux_lock);
adc->soc_data = soc_data;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
ret = devm_request_irq(dev, irq, ingenic_adc_irq, 0,
dev_name(dev), iio_dev);
if (ret < 0) {
dev_err(dev, "Failed to request irq: %d\n", ret);
return ret;
}
adc->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(adc->base))
return PTR_ERR(adc->base);
adc->clk = devm_clk_get(dev, "adc");
if (IS_ERR(adc->clk)) {
dev_err(dev, "Unable to get clock\n");
return PTR_ERR(adc->clk);
}
ret = clk_prepare_enable(adc->clk);
if (ret) {
dev_err(dev, "Failed to enable clock\n");
return ret;
}
/* Set clock dividers. */
if (soc_data->init_clk_div) {
ret = soc_data->init_clk_div(dev, adc);
if (ret) {
clk_disable_unprepare(adc->clk);
return ret;
}
}
/* Put hardware in a known passive state. */
writeb(0x00, adc->base + JZ_ADC_REG_ENABLE);
writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
/* JZ4760B specific */
if (device_property_present(dev, "ingenic,use-internal-divider"))
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_VBAT_SEL,
JZ_ADC_REG_CFG_VBAT_SEL);
else
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_VBAT_SEL, 0);
usleep_range(2000, 3000); /* Must wait at least 2ms. */
clk_disable(adc->clk);
ret = devm_add_action_or_reset(dev, ingenic_adc_clk_cleanup, adc->clk);
if (ret) {
dev_err(dev, "Unable to add action\n");
return ret;
}
iio_dev->name = "jz-adc";
iio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
iio_dev->setup_ops = &ingenic_buffer_setup_ops;
iio_dev->channels = soc_data->channels;
iio_dev->num_channels = soc_data->num_channels;
iio_dev->info = &ingenic_adc_info;
ret = devm_iio_device_register(dev, iio_dev);
if (ret)
dev_err(dev, "Unable to register IIO device\n");
return ret;
}
static const struct of_device_id ingenic_adc_of_match[] = {
{ .compatible = "ingenic,jz4725b-adc", .data = &jz4725b_adc_soc_data, },
{ .compatible = "ingenic,jz4740-adc", .data = &jz4740_adc_soc_data, },
{ .compatible = "ingenic,jz4760-adc", .data = &jz4760_adc_soc_data, },
{ .compatible = "ingenic,jz4760b-adc", .data = &jz4760_adc_soc_data, },
{ .compatible = "ingenic,jz4770-adc", .data = &jz4770_adc_soc_data, },
{ },
};
MODULE_DEVICE_TABLE(of, ingenic_adc_of_match);
static struct platform_driver ingenic_adc_driver = {
.driver = {
.name = "ingenic-adc",
.of_match_table = ingenic_adc_of_match,
},
.probe = ingenic_adc_probe,
};
module_platform_driver(ingenic_adc_driver);
MODULE_LICENSE("GPL v2");
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