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iio: adc: at91-sama5d2_adc: handle different EMR.OSR for different hw versions

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SAMA7G5 introduces 64 and 256 oversampling rates. Due to this EMR.OSR is 3
bits long. Change the code to reflect this. Commit prepares the code
for the addition of 64 and 256 oversampling rates.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220803102855.2191070-7-claudiu.beznea@microchip.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Claudiu Beznea 2022-08-03 13:28:42 +03:00 committed by Jonathan Cameron
parent cf15a2b518
commit 287c271dee
1 changed files with 18 additions and 13 deletions
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31
drivers/iio/adc/at91-sama5d2_adc.c
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@ -138,8 +138,7 @@ struct at91_adc_reg_layout {
/* Extended Mode Register */
u16 EMR;
/* Extended Mode Register - Oversampling rate */
#define AT91_SAMA5D2_EMR_OSR(V) ((V) << 16)
#define AT91_SAMA5D2_EMR_OSR_MASK GENMASK(17, 16)
#define AT91_SAMA5D2_EMR_OSR(V, M) (((V) << 16) & (M))
#define AT91_SAMA5D2_EMR_OSR_1SAMPLES 0
#define AT91_SAMA5D2_EMR_OSR_4SAMPLES 1
#define AT91_SAMA5D2_EMR_OSR_16SAMPLES 2
@ -403,6 +402,7 @@ static const struct at91_adc_reg_layout sama7g5_layout = {
* @max_index: highest channel index (highest index may be higher
* than the total channel number)
* @hw_trig_cnt: number of possible hardware triggers
* @osr_mask: oversampling ratio bitmask on EMR register
*/
struct at91_adc_platform {
const struct at91_adc_reg_layout *layout;
@ -414,6 +414,7 @@ struct at91_adc_platform {
unsigned int max_channels;
unsigned int max_index;
unsigned int hw_trig_cnt;
unsigned int osr_mask;
};
/**
@ -612,6 +613,7 @@ static const struct at91_adc_platform sama5d2_platform = {
.max_index = AT91_SAMA5D2_MAX_CHAN_IDX,
#define AT91_SAMA5D2_HW_TRIG_CNT 3
.hw_trig_cnt = AT91_SAMA5D2_HW_TRIG_CNT,
.osr_mask = GENMASK(17, 16),
};
static const struct at91_adc_platform sama7g5_platform = {
@ -627,6 +629,7 @@ static const struct at91_adc_platform sama7g5_platform = {
.max_index = AT91_SAMA7G5_MAX_CHAN_IDX,
#define AT91_SAMA7G5_HW_TRIG_CNT 3
.hw_trig_cnt = AT91_SAMA7G5_HW_TRIG_CNT,
.osr_mask = GENMASK(18, 16),
};
static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan)
@ -725,30 +728,32 @@ static void at91_adc_eoc_ena(struct at91_adc_state *st, unsigned int channel)
at91_adc_writel(st, EOC_IER, BIT(channel));
}
static void at91_adc_config_emr(struct at91_adc_state *st)
static void at91_adc_config_emr(struct at91_adc_state *st,
u32 oversampling_ratio)
{
/* configure the extended mode register */
unsigned int emr = at91_adc_readl(st, EMR);
unsigned int osr_mask = st->soc_info.platform->osr_mask;
/* select oversampling per single trigger event */
emr |= AT91_SAMA5D2_EMR_ASTE(1);
/* delete leftover content if it's the case */
emr &= ~AT91_SAMA5D2_EMR_OSR_MASK;
emr &= ~osr_mask;
/* select oversampling ratio from configuration */
switch (st->oversampling_ratio) {
switch (oversampling_ratio) {
case AT91_OSR_1SAMPLES:
emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_1SAMPLES) &
AT91_SAMA5D2_EMR_OSR_MASK;
emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_1SAMPLES,
osr_mask);
break;
case AT91_OSR_4SAMPLES:
emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_4SAMPLES) &
AT91_SAMA5D2_EMR_OSR_MASK;
emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_4SAMPLES,
osr_mask);
break;
case AT91_OSR_16SAMPLES:
emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_16SAMPLES) &
AT91_SAMA5D2_EMR_OSR_MASK;
emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_16SAMPLES,
osr_mask);
break;
}
@ -1658,7 +1663,7 @@ static int at91_adc_write_raw(struct iio_dev *indio_dev,
mutex_lock(&st->lock);
st->oversampling_ratio = val;
/* update ratio */
at91_adc_config_emr(st);
at91_adc_config_emr(st, val);
mutex_unlock(&st->lock);
iio_device_release_direct_mode(indio_dev);
return 0;
@ -1838,7 +1843,7 @@ static void at91_adc_hw_init(struct iio_dev *indio_dev)
at91_adc_setup_samp_freq(indio_dev, st->soc_info.min_sample_rate);
/* configure extended mode register */
at91_adc_config_emr(st);
at91_adc_config_emr(st, st->oversampling_ratio);
}
static ssize_t at91_adc_get_fifo_state(struct device *dev,