diff options
| author | Antoniu Miclaus <antoniu.miclaus@analog.com> | 2026-08-26 14:16:13 +0300 |
|---|---|---|
| committer | Jonathan Cameron <jonathan.cameron@oss.qualcomm.com> | 2026-08-31 02:58:31 +0100 |
| commit | 783211907c2df6e8a1cce892a67d99c943ef6404 (patch) | |
| tree | cb06cfb3085db86e585cca90738838d62d96a05b /drivers/iio | |
| parent | 03389bea2ec76e0ffe4865b4d6cec575ac9f98b8 (diff) | |
iio: adc: ad4080: allow debugfs register access to both channels
The dual-channel parts (AD4880/AD4883/AD4884) are built from two
independent ADC dies, each with its own SPI chip select and register
map. They are presented as a single IIO device because the FPGA
interleaves both dies into one DMA stream, so only one direct_reg_access
debugfs file is created and it can only reach channel A's regmap. Channel
B's registers are therefore inaccessible, which blocks bring-up and
debugging of the second die.
Select the target die through the debugfs register address: the low 8
bits are the register offset and the upper bits are the channel index
(0x0nn selects channel A, 0x1nn channel B). A read returns the real
register value of the selected die and each die is addressed
independently; single-channel parts only accept channel 0.
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Diffstat (limited to 'drivers/iio')
| -rw-r--r-- | drivers/iio/adc/ad4080.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/iio/adc/ad4080.c b/drivers/iio/adc/ad4080.c index 04cd6628ebff..994625a7cf8b 100644 --- a/drivers/iio/adc/ad4080.c +++ b/drivers/iio/adc/ad4080.c @@ -145,6 +145,10 @@ #define AD4080_MAX_SAMP_FREQ 40000000 #define AD4080_MIN_SAMP_FREQ 1250000 +/* debugfs direct_reg_access channel windowing: 0x0RR = ch0, 0x1RR = ch1 */ +#define AD4080_DEBUGFS_REG_CH_MSK GENMASK(15, 8) +#define AD4080_DEBUGFS_REG_OFFSET_MSK GENMASK(7, 0) + enum ad4080_filter_type { FILTER_NONE, SINC_1, @@ -210,11 +214,16 @@ static int ad4080_reg_access(struct iio_dev *indio_dev, unsigned int reg, unsigned int writeval, unsigned int *readval) { struct ad4080_state *st = iio_priv(indio_dev); + unsigned int ch = FIELD_GET(AD4080_DEBUGFS_REG_CH_MSK, reg); + unsigned int offset = FIELD_GET(AD4080_DEBUGFS_REG_OFFSET_MSK, reg); + + if (ch >= st->info->num_channels) + return -EINVAL; if (readval) - return regmap_read(st->regmap[0], reg, readval); + return regmap_read(st->regmap[ch], offset, readval); - return regmap_write(st->regmap[0], reg, writeval); + return regmap_write(st->regmap[ch], offset, writeval); } static int ad4080_get_scale(struct ad4080_state *st, int *val, int *val2) |