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IIO: Ingenic JZ47xx: Add support for JZ4770 SoC ADC.

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Add support for the ADC hardware present on Ingenic JZ4770 SoC.

Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
Tested-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Artur Rojek 2019-07-27 21:59:40 +02:00 committed by Jonathan Cameron
parent b23bf21f55
commit a515d64885
1 changed files with 127 additions and 22 deletions
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149
drivers/iio/adc/ingenic-adc.c
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@ -25,9 +25,13 @@
#define JZ_ADC_REG_ADSDAT 0x20
#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_ADCLK_CLKDIV_LSB 0
#define JZ_ADC_REG_ADCLK_CLKDIV10US_LSB 16
#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_AUX_VREF 3300
#define JZ_ADC_AUX_VREF_BITS 12
@ -37,6 +41,8 @@
#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 JZ4770_ADC_BATTERY_VREF 6600
#define JZ4770_ADC_BATTERY_VREF_BITS 12
struct ingenic_adc;
@ -47,6 +53,8 @@ struct ingenic_adc_soc_data {
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_aux2: 1;
int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc);
};
@ -54,6 +62,7 @@ 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;
};
@ -120,6 +129,8 @@ static int ingenic_adc_write_raw(struct iio_dev *iio_dev,
case IIO_CHAN_INFO_SCALE:
switch (chan->channel) {
case INGENIC_ADC_BATTERY:
if (!adc->soc_data->battery_vref_mode)
return -EINVAL;
if (val > JZ_ADC_BATTERY_LOW_VREF) {
ingenic_adc_set_config(adc,
JZ_ADC_REG_CFG_BAT_MD,
@ -158,6 +169,14 @@ static const int jz4740_adc_battery_scale_avail[] = {
JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_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;
@ -187,7 +206,45 @@ static int jz4725b_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
/* We also need a divider that produces a 10us clock. */
div_10us = DIV_ROUND_UP(rate, 100000);
writel(((div_10us - 1) << JZ_ADC_REG_ADCLK_CLKDIV10US_LSB) |
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);
@ -201,6 +258,8 @@ static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
.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_aux2 = false,
.init_clk_div = jz4725b_adc_init_clk_div,
};
@ -211,9 +270,23 @@ static const struct ingenic_adc_soc_data jz4740_adc_soc_data = {
.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_aux2 = false,
.init_clk_div = NULL, /* no ADCLK register on JZ4740 */
};
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_aux2 = true,
.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,
@ -239,6 +312,42 @@ static int ingenic_adc_read_avail(struct iio_dev *iio_dev,
};
}
static int ingenic_adc_read_chan_info_raw(struct ingenic_adc *adc,
struct iio_chan_spec const *chan,
int *val)
{
int bit, ret, engine = (chan->channel == INGENIC_ADC_BATTERY);
/* We cannot sample AUX/AUX2 in parallel. */
mutex_lock(&adc->aux_lock);
if (adc->soc_data->has_aux2 && engine == 0) {
bit = BIT(chan->channel == INGENIC_ADC_AUX2);
ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, bit);
}
clk_enable(adc->clk);
ret = ingenic_adc_capture(adc, engine);
if (ret)
goto out;
switch (chan->channel) {
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:
clk_disable(adc->clk);
mutex_unlock(&adc->aux_lock);
return ret;
}
static int ingenic_adc_read_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan,
int *val,
@ -246,32 +355,14 @@ static int ingenic_adc_read_raw(struct iio_dev *iio_dev,
long m)
{
struct ingenic_adc *adc = iio_priv(iio_dev);
int ret;
switch (m) {
case IIO_CHAN_INFO_RAW:
clk_enable(adc->clk);
ret = ingenic_adc_capture(adc, chan->channel);
if (ret) {
clk_disable(adc->clk);
return ret;
}
switch (chan->channel) {
case INGENIC_ADC_AUX:
*val = readw(adc->base + JZ_ADC_REG_ADSDAT);
break;
case INGENIC_ADC_BATTERY:
*val = readw(adc->base + JZ_ADC_REG_ADBDAT);
break;
}
clk_disable(adc->clk);
return IIO_VAL_INT;
return ingenic_adc_read_chan_info_raw(adc, chan, val);
case IIO_CHAN_INFO_SCALE:
switch (chan->channel) {
case INGENIC_ADC_AUX:
case INGENIC_ADC_AUX2:
*val = JZ_ADC_AUX_VREF;
*val2 = JZ_ADC_AUX_VREF_BITS;
break;
@ -322,6 +413,14 @@ static const struct iio_chan_spec ingenic_channels[] = {
.indexed = 1,
.channel = INGENIC_ADC_BATTERY,
},
{ /* Must always be last in the array. */
.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,
},
};
static int ingenic_adc_probe(struct platform_device *pdev)
@ -343,6 +442,7 @@ static int ingenic_adc_probe(struct platform_device *pdev)
adc = iio_priv(iio_dev);
mutex_init(&adc->lock);
mutex_init(&adc->aux_lock);
adc->soc_data = soc_data;
mem_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@ -374,6 +474,7 @@ static int ingenic_adc_probe(struct platform_device *pdev)
/* Put hardware in a known passive state. */
writeb(0x00, adc->base + JZ_ADC_REG_ENABLE);
writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
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);
@ -387,6 +488,9 @@ static int ingenic_adc_probe(struct platform_device *pdev)
iio_dev->modes = INDIO_DIRECT_MODE;
iio_dev->channels = ingenic_channels;
iio_dev->num_channels = ARRAY_SIZE(ingenic_channels);
/* Remove AUX2 from the list of supported channels. */
if (!adc->soc_data->has_aux2)
iio_dev->num_channels -= 1;
iio_dev->info = &ingenic_adc_info;
ret = devm_iio_device_register(dev, iio_dev);
@ -400,6 +504,7 @@ static int ingenic_adc_probe(struct platform_device *pdev)
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,jz4770-adc", .data = &jz4770_adc_soc_data, },
{ },
};
MODULE_DEVICE_TABLE(of, ingenic_adc_of_match);