The chip support oversampling ratio so expose it to userspace.
Signed-off-by: Marcus Folkesson <[email protected]>
---
drivers/iio/adc/mcp3911.c | 72 +++++++++++++++++++++++++++++++++++++++
1 file changed, 72 insertions(+)
diff --git a/drivers/iio/adc/mcp3911.c b/drivers/iio/adc/mcp3911.c
index e761feed5303..65831bef12f6 100644
--- a/drivers/iio/adc/mcp3911.c
+++ b/drivers/iio/adc/mcp3911.c
@@ -5,6 +5,8 @@
* Copyright (C) 2018 Marcus Folkesson <[email protected]>
* Copyright (C) 2018 Kent Gustavsson <[email protected]>
*/
+#include <linux/bitfield.h>
+#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
@@ -35,6 +37,7 @@
#define MCP3911_REG_CONFIG 0x0c
#define MCP3911_CONFIG_CLKEXT BIT(1)
#define MCP3911_CONFIG_VREFEXT BIT(2)
+#define MCP3911_CONFIG_OSR GENMASK(13, 11)
#define MCP3911_REG_OFFCAL_CH0 0x0e
#define MCP3911_REG_GAINCAL_CH0 0x11
@@ -53,6 +56,8 @@
#define MCP3911_NUM_CHANNELS 2
+static const int mcp3911_osr_table[] = {32, 64, 128, 256, 512, 1024, 2048, 4096};
+
struct mcp3911 {
struct spi_device *spi;
struct mutex lock;
@@ -108,6 +113,22 @@ static int mcp3911_update(struct mcp3911 *adc, u8 reg, u32 mask,
return mcp3911_write(adc, reg, val, len);
}
+
+static int mcp3911_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long info)
+{
+ switch (info) {
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ *type = IIO_VAL_INT;
+ *vals = mcp3911_osr_table;
+ *length = ARRAY_SIZE(mcp3911_osr_table);
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
static int mcp3911_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int *val,
int *val2, long mask)
@@ -134,6 +155,16 @@ static int mcp3911_read_raw(struct iio_dev *indio_dev,
ret = IIO_VAL_INT;
break;
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ ret = mcp3911_read(adc,
+ MCP3911_REG_CONFIG, val, 2);
+ if (ret)
+ goto out;
+
+ *val = FIELD_GET(MCP3911_CONFIG_OSR, *val);
+ *val = 32 << *val;
+ ret = IIO_VAL_INT;
+ break;
case IIO_CHAN_INFO_SCALE:
if (adc->vref) {
@@ -186,6 +217,42 @@ static int mcp3911_write_raw(struct iio_dev *indio_dev,
MCP3911_STATUSCOM_EN_OFFCAL,
MCP3911_STATUSCOM_EN_OFFCAL, 2);
break;
+
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ switch (val) {
+ case 4096:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x07);
+ break;
+ case 2048:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x06);
+ break;
+ case 1024:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x05);
+ break;
+ case 512:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x04);
+ break;
+ case 256:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x03);
+ break;
+ case 128:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x02);
+ break;
+ case 64:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x01);
+ break;
+ case 32:
+ val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x00);
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = mcp3911_update(adc, MCP3911_REG_CONFIG,
+ MCP3911_CONFIG_OSR,
+ val, 2);
+ break;
}
out:
@@ -198,9 +265,13 @@ static int mcp3911_write_raw(struct iio_dev *indio_dev,
.indexed = 1, \
.channel = idx, \
.scan_index = idx, \
+ .scan_index = idx, \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_OFFSET) | \
BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_type_available = \
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
.scan_type = { \
.sign = 's', \
.realbits = 24, \
@@ -252,6 +323,7 @@ static irqreturn_t mcp3911_trigger_handler(int irq, void *p)
static const struct iio_info mcp3911_info = {
.read_raw = mcp3911_read_raw,
.write_raw = mcp3911_write_raw,
+ .read_avail = mcp3911_read_avail,
};
static irqreturn_t mcp3911_interrupt(int irq, void *dev_id)
--
2.36.1
On Thu, Jun 23, 2022 at 9:08 PM Marcus Folkesson
<[email protected]> wrote:
>
> The chip support oversampling ratio so expose it to userspace.
supports
ratio, so
...
> +static const int mcp3911_osr_table[] = {32, 64, 128, 256, 512, 1024, 2048, 4096};
Spaces inside {}.
...
> }
>
> +
Unwanted blank line.
...
> + switch (val) {
> + case 4096:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x07);
> + break;
> + case 2048:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x06);
> + break;
> + case 1024:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x05);
> + break;
> + case 512:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x04);
> + break;
> + case 256:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x03);
> + break;
> + case 128:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x02);
> + break;
> + case 64:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x01);
> + break;
> + case 32:
> + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x00);
> + break;
> + default:
> + ret = -EINVAL;
> + goto out;
> + }
I understood why the table above, but this is a waste of resources.
Use that table
...
> + ret = mcp3911_update(adc, MCP3911_REG_CONFIG,
> + MCP3911_CONFIG_OSR,
> + val, 2);
sizeof() ?
--
With Best Regards,
Andy Shevchenko
On Thu, Jun 23, 2022 at 09:20:01PM +0200, Andy Shevchenko wrote:
> On Thu, Jun 23, 2022 at 9:08 PM Marcus Folkesson
> <[email protected]> wrote:
> >
> > The chip support oversampling ratio so expose it to userspace.
>
> supports
>
> ratio, so
>
> ...
Thanks
>
> > +static const int mcp3911_osr_table[] = {32, 64, 128, 256, 512, 1024, 2048, 4096};
>
> Spaces inside {}.
Not sure what you mean?
>
> ...
>
> > }
> >
> > +
>
> Unwanted blank line.
>
> ...
Removed
>
> > + switch (val) {
> > + case 4096:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x07);
> > + break;
> > + case 2048:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x06);
> > + break;
> > + case 1024:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x05);
> > + break;
> > + case 512:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x04);
> > + break;
> > + case 256:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x03);
> > + break;
> > + case 128:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x02);
> > + break;
> > + case 64:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x01);
> > + break;
> > + case 32:
> > + val = FIELD_PREP(MCP3911_CONFIG_OSR, 0x00);
> > + break;
> > + default:
> > + ret = -EINVAL;
> > + goto out;
> > + }
>
> I understood why the table above, but this is a waste of resources.
> Use that table
Yep, I will use the table instead
>
> ...
>
> > + ret = mcp3911_update(adc, MCP3911_REG_CONFIG,
> > + MCP3911_CONFIG_OSR,
> > + val, 2);
>
> sizeof() ?
sizeof() what?
Thanks,
Marcus Folkesson
On Fri, Jun 24, 2022 at 2:07 PM Marcus Folkesson
<[email protected]> wrote:
> On Thu, Jun 23, 2022 at 09:20:01PM +0200, Andy Shevchenko wrote:
> > On Thu, Jun 23, 2022 at 9:08 PM Marcus Folkesson
> > <[email protected]> wrote:
...
> > > +static const int mcp3911_osr_table[] = {32, 64, 128, 256, 512, 1024, 2048, 4096};
> >
> > Spaces inside {}.
>
> Not sure what you mean?
int foo = { 1, 2, 3 };
...
> > > + ret = mcp3911_update(adc, MCP3911_REG_CONFIG,
> > > + MCP3911_CONFIG_OSR,
> > > + val, 2);
> >
> > sizeof() ?
>
> sizeof() what?
sizeof(val) ?
--
With Best Regards,
Andy Shevchenko