[PATCH v2 3/4] iio: amplifiers: hmc425a: move conversion logic

From: Dumitru Ceclan
Date: Wed Jan 10 2024 - 10:39:35 EST


Move gain-dB<->code conversion logic from read_raw and write_raw to
hmc425a_gain_dB_to_code() and hmc425a_code_to_gain_dB().

Signed-off-by: Dumitru Ceclan <mitrutzceclan@xxxxxxxxx>
---
drivers/iio/amplifiers/hmc425a.c | 100 ++++++++++++++++++-------------
1 file changed, 57 insertions(+), 43 deletions(-)

diff --git a/drivers/iio/amplifiers/hmc425a.c b/drivers/iio/amplifiers/hmc425a.c
index ed4d72922696..b5fd19403d15 100644
--- a/drivers/iio/amplifiers/hmc425a.c
+++ b/drivers/iio/amplifiers/hmc425a.c
@@ -56,35 +56,70 @@ static int hmc425a_write(struct iio_dev *indio_dev, u32 value)
return 0;
}

+static int hmc425a_gain_dB_to_code(struct hmc425a_state *st, int val, int val2, int *code)
+{
+ struct hmc425a_chip_info *inf = st->chip_info;
+ int gain, temp;
+
+ if (val < 0)
+ gain = (val * 1000) - (val2 / 1000);
+ else
+ gain = (val * 1000) + (val2 / 1000);
+
+ if (gain > inf->gain_max || gain < inf->gain_min)
+ return -EINVAL;
+
+ switch (st->type) {
+ case ID_HMC425A:
+ *code = ~((abs(gain) / 500) & 0x3F);
+ break;
+ case ID_HMC540S:
+ *code = ~((abs(gain) / 1000) & 0xF);
+ break;
+ case ID_ADRF5740:
+ temp = (abs(gain) / 2000) & 0xF;
+ *code = temp & BIT(3) ? temp | BIT(2) : temp;
+ break;
+ }
+ return 0;
+}
+
+static int hmc425a_code_to_gain_dB(struct hmc425a_state *st, int *val, int *val2)
+{
+ int code, gain;
+
+ code = st->gain;
+ switch (st->type) {
+ case ID_HMC425A:
+ gain = ~code * -500;
+ break;
+ case ID_HMC540S:
+ gain = ~code * -1000;
+ break;
+ case ID_ADRF5740:
+ code = code & BIT(3) ? code & ~BIT(2) : code;
+ gain = code * -2000;
+ break;
+ }
+
+ *val = gain / 1000;
+ *val2 = (gain % 1000) * 1000;
+ return 0;
+}
+
static int hmc425a_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val,
int *val2, long m)
{
struct hmc425a_state *st = iio_priv(indio_dev);
- int code, gain = 0;
int ret;

mutex_lock(&st->lock);
switch (m) {
case IIO_CHAN_INFO_HARDWAREGAIN:
- code = st->gain;
-
- switch (st->type) {
- case ID_HMC425A:
- gain = ~code * -500;
- break;
- case ID_HMC540S:
- gain = ~code * -1000;
- break;
- case ID_ADRF5740:
- code = code & BIT(3) ? code & ~BIT(2) : code;
- gain = code * -2000;
+ ret = hmc425a_code_to_gain_dB(st, val, val2);
+ if (ret)
break;
- }
-
- *val = gain / 1000;
- *val2 = (gain % 1000) * 1000;
-
ret = IIO_VAL_INT_PLUS_MICRO_DB;
break;
default:
@@ -100,36 +135,15 @@ static int hmc425a_write_raw(struct iio_dev *indio_dev,
int val2, long mask)
{
struct hmc425a_state *st = iio_priv(indio_dev);
- struct hmc425a_chip_info *inf = st->chip_info;
- int code = 0, gain;
- int ret;
-
- if (val < 0)
- gain = (val * 1000) - (val2 / 1000);
- else
- gain = (val * 1000) + (val2 / 1000);
-
- if (gain > inf->gain_max || gain < inf->gain_min)
- return -EINVAL;
-
- switch (st->type) {
- case ID_HMC425A:
- code = ~((abs(gain) / 500) & 0x3F);
- break;
- case ID_HMC540S:
- code = ~((abs(gain) / 1000) & 0xF);
- break;
- case ID_ADRF5740:
- code = (abs(gain) / 2000) & 0xF;
- code = code & BIT(3) ? code | BIT(2) : code;
- break;
- }
+ int code = 0, ret;

mutex_lock(&st->lock);
switch (mask) {
case IIO_CHAN_INFO_HARDWAREGAIN:
+ ret = hmc425a_gain_dB_to_code(st, val, val2, &code);
+ if (ret)
+ break;
st->gain = code;
-
ret = hmc425a_write(indio_dev, st->gain);
break;
default:
--
2.42.0