Adds support for IIO Trigger. Optionally, gp1 is assigned as Data Ready
signal, if not present, fallback to an I3C IBI with the same role.
The software trigger is allocated by the device, but must be attached by
the user before enabling the buffer. The purpose is to not impede
removing the driver due to the increased reference count when
iio_trigger_set_immutable or iio_trigger_get is used.
Signed-off-by: Jorge Marques <jorge.marques@analog.com>
---
drivers/iio/adc/Kconfig | 2 +
drivers/iio/adc/ad4062.c | 164 +++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 161 insertions(+), 5 deletions(-)
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index e506dbe83f488..ddb7820f0bdcc 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -74,6 +74,8 @@ config AD4062
tristate "Analog Devices AD4062 Driver"
depends on I3C
select REGMAP_I3C
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
help
Say yes here to build support for Analog Devices AD4062 I3C analog
to digital converters (ADC).
diff --git a/drivers/iio/adc/ad4062.c b/drivers/iio/adc/ad4062.c
index 6866393ffef8d..4e4be7358047f 100644
--- a/drivers/iio/adc/ad4062.c
+++ b/drivers/iio/adc/ad4062.c
@@ -12,8 +12,12 @@
#include <linux/err.h>
#include <linux/i3c/device.h>
#include <linux/i3c/master.h>
+#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/math.h>
@@ -60,6 +64,7 @@
#define AD4062_REG_DEVICE_STATUS_DEVICE_RESET BIT(6)
#define AD4062_REG_IBI_STATUS 0x48
#define AD4062_REG_CONV_READ_LSB 0x50
+#define AD4062_REG_CONV_READ 0x53
#define AD4062_REG_CONV_TRIGGER 0x59
#define AD4062_REG_CONV_AUTO 0x61
#define AD4062_MAX_REG AD4062_REG_CONV_AUTO
@@ -134,6 +139,7 @@ struct ad4062_state {
const struct ad4062_chip_info *chip;
const struct ad4062_bus_ops *ops;
enum ad4062_operation_mode mode;
+ struct work_struct trig_conv;
struct completion completion;
struct iio_trigger *trigger;
struct iio_dev *indio_dev;
@@ -143,6 +149,7 @@ struct ad4062_state {
int vref_uv;
int samp_freqs[ARRAY_SIZE(ad4062_conversion_freqs)];
u8 oversamp_ratio;
+ bool gpo_irq[2];
union {
__be32 be32;
__be16 be16;
@@ -396,7 +403,10 @@ static irqreturn_t ad4062_irq_handler_drdy(int irq, void *private)
struct iio_dev *indio_dev = private;
struct ad4062_state *st = iio_priv(indio_dev);
- complete(&st->completion);
+ if (iio_buffer_enabled(indio_dev) && iio_trigger_using_own(indio_dev))
+ iio_trigger_poll(st->trigger);
+ else
+ complete(&st->completion);
return IRQ_HANDLED;
}
@@ -406,7 +416,56 @@ static void ad4062_ibi_handler(struct i3c_device *i3cdev,
{
struct ad4062_state *st = i3cdev_get_drvdata(i3cdev);
- complete(&st->completion);
+ if (iio_buffer_enabled(st->indio_dev))
+ iio_trigger_poll_nested(st->trigger);
+ else
+ complete(&st->completion);
+}
+
+static void ad4062_trigger_work(struct work_struct *work)
+{
+ struct ad4062_state *st = container_of(work, struct ad4062_state,
+ trig_conv);
+ int ret;
+
+ /* Read current conversion, if at reg CONV_READ, stop bit triggers
+ * next sample and does not need writing the address.
+ */
+ struct i3c_priv_xfer t[2] = {
+ {
+ .data.in = &st->buf.be32,
+ .len = sizeof(st->buf.be32),
+ .rnw = true,
+ },
+ {
+ .data.out = &st->reg_addr_conv,
+ .len = sizeof(st->reg_addr_conv),
+ .rnw = false,
+ },
+ };
+
+ ret = i3c_device_do_priv_xfers(st->i3cdev, &t[0], 1);
+ if (ret)
+ return;
+
+ iio_push_to_buffers_with_timestamp(st->indio_dev, &st->buf.be32,
+ iio_get_time_ns(st->indio_dev));
+ if (st->gpo_irq[1])
+ return;
+
+ i3c_device_do_priv_xfers(st->i3cdev, &t[1], 1);
+}
+
+static irqreturn_t ad4062_poll_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad4062_state *st = iio_priv(indio_dev);
+
+ iio_trigger_notify_done(indio_dev->trig);
+ schedule_work(&st->trig_conv);
+
+ return IRQ_HANDLED;
}
static void ad4062_remove_ibi(void *data)
@@ -451,10 +510,14 @@ static int ad4062_request_irq(struct iio_dev *indio_dev)
if (ret == -EPROBE_DEFER) {
return ret;
} else if (ret < 0) {
+ st->gpo_irq[1] = false;
+ st->reg_addr_conv = AD4062_REG_CONV_TRIGGER;
ret = regmap_update_bits(st->regmap, AD4062_REG_ADC_IBI_EN,
AD4062_REG_ADC_IBI_EN_CONV_TRIGGER,
AD4062_REG_ADC_IBI_EN_CONV_TRIGGER);
} else {
+ st->gpo_irq[1] = true;
+ st->reg_addr_conv = AD4062_REG_CONV_READ;
ret = devm_request_threaded_irq(dev, ret,
ad4062_irq_handler_drdy,
NULL, IRQF_ONESHOT, indio_dev->name,
@@ -464,6 +527,34 @@ static int ad4062_request_irq(struct iio_dev *indio_dev)
return ret;
}
+static const struct iio_trigger_ops ad4062_trigger_ops = {
+ .validate_device = &iio_trigger_validate_own_device,
+};
+
+static int ad4062_request_trigger(struct iio_dev *indio_dev)
+{
+ struct ad4062_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->i3cdev->dev;
+ int ret;
+
+ st->trigger = devm_iio_trigger_alloc(dev, "%s-dev%d",
+ indio_dev->name,
+ iio_device_id(indio_dev));
+ if (!st->trigger)
+ return -ENOMEM;
+
+ st->trigger->ops = &ad4062_trigger_ops;
+ iio_trigger_set_drvdata(st->trigger, indio_dev);
+
+ ret = devm_iio_trigger_register(dev, st->trigger);
+ if (ret)
+ return ret;
+
+ indio_dev->trig = iio_trigger_get(st->trigger);
+
+ return 0;
+}
+
static const int ad4062_oversampling_avail[] = {
1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096,
};
@@ -579,8 +670,8 @@ static int __ad4062_read_chan_raw(struct ad4062_state *st, int *val)
int ret;
reinit_completion(&st->completion);
- /* Change address pointer to trigger conversion */
- ret = i3c_device_do_priv_xfers(i3cdev, &t[0], 1);
+ /* Change address pointer (and read if CONV_READ) to trigger conversion. */
+ ret = i3c_device_do_priv_xfers(i3cdev, t, st->gpo_irq[1] ? 2 : 1);
if (ret)
return ret;
/*
@@ -689,6 +780,57 @@ static int ad4062_write_raw(struct iio_dev *indio_dev,
return ret;
}
+static int ad4062_triggered_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct ad4062_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = pm_runtime_resume_and_get(&st->i3cdev->dev);
+ if (ret)
+ return ret;
+
+ ret = ad4062_set_operation_mode(st, st->mode);
+ if (ret)
+ goto out_mode_error;
+
+ /* CONV_READ requires read to trigger first sample. */
+ struct i3c_priv_xfer t[2] = {
+ {
+ .data.out = &st->reg_addr_conv,
+ .len = sizeof(st->reg_addr_conv),
+ .rnw = false,
+ },
+ {
+ .data.in = &st->buf.be32,
+ .len = sizeof(st->buf.be32),
+ .rnw = true,
+ }
+ };
+
+ ret = i3c_device_do_priv_xfers(st->i3cdev, t, st->gpo_irq[1] ? 2 : 1);
+ if (ret)
+ goto out_mode_error;
+ return 0;
+
+out_mode_error:
+ pm_runtime_put_autosuspend(&st->i3cdev->dev);
+
+ return ret;
+}
+
+static int ad4062_triggered_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct ad4062_state *st = iio_priv(indio_dev);
+
+ pm_runtime_put_autosuspend(&st->i3cdev->dev);
+ return 0;
+}
+
+static const struct iio_buffer_setup_ops ad4062_triggered_buffer_setup_ops = {
+ .postenable = &ad4062_triggered_buffer_postenable,
+ .predisable = &ad4062_triggered_buffer_predisable,
+};
+
static int ad4062_debugfs_reg_access(struct iio_dev *indio_dev, unsigned int reg,
unsigned int writeval, unsigned int *readval)
{
@@ -801,7 +943,6 @@ static int ad4062_probe(struct i3c_device *i3cdev)
st->sampling_frequency = 0;
st->oversamp_ratio = BIT(0);
st->indio_dev = indio_dev;
- st->reg_addr_conv = AD4062_REG_CONV_TRIGGER;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->num_channels = 1;
@@ -825,6 +966,17 @@ static int ad4062_probe(struct i3c_device *i3cdev)
if (ret)
return ret;
+ ret = ad4062_request_trigger(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_triggered_buffer_setup(&i3cdev->dev, indio_dev,
+ iio_pollfunc_store_time,
+ ad4062_poll_handler,
+ &ad4062_triggered_buffer_setup_ops);
+ if (ret)
+ return ret;
+
pm_runtime_set_active(dev);
ret = devm_pm_runtime_enable(dev);
if (ret)
@@ -837,6 +989,8 @@ static int ad4062_probe(struct i3c_device *i3cdev)
if (ret)
return dev_err_probe(dev, ret, "Failed to request i3c ibi\n");
+ INIT_WORK(&st->trig_conv, ad4062_trigger_work);
+
return devm_iio_device_register(dev, indio_dev);
}
--
2.51.1On Mon, Nov 24, 2025 at 10:18:04AM +0100, Jorge Marques wrote:
> Adds support for IIO Trigger. Optionally, gp1 is assigned as Data Ready
> signal, if not present, fallback to an I3C IBI with the same role.
> The software trigger is allocated by the device, but must be attached by
> the user before enabling the buffer. The purpose is to not impede
> removing the driver due to the increased reference count when
> iio_trigger_set_immutable or iio_trigger_get is used.
We refer to the functions as func(). Mind the parentheses.
...
> + struct ad4062_state *st = container_of(work, struct ad4062_state,
> + trig_conv);
I think the
struct ad4062_state *st =
container_of(work, struct ad4062_state, trig_conv);
reads better.
> + int ret;
...
> + /* Read current conversion, if at reg CONV_READ, stop bit triggers
> + * next sample and does not need writing the address.
> + */
/*
* The multi-line comment style is as in
* this example. Please, check and update.
*/
> +static irqreturn_t ad4062_poll_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio_dev = pf->indio_dev;
> + struct ad4062_state *st = iio_priv(indio_dev);
> +
> + iio_trigger_notify_done(indio_dev->trig);
> + schedule_work(&st->trig_conv);
> +
> + return IRQ_HANDLED;
> }
...
> +static int ad4062_triggered_buffer_postenable(struct iio_dev *indio_dev)
> +{
> + struct ad4062_state *st = iio_priv(indio_dev);
> + int ret;
> +
> + ret = pm_runtime_resume_and_get(&st->i3cdev->dev);
> + if (ret)
> + return ret;
> +
> + ret = ad4062_set_operation_mode(st, st->mode);
> + if (ret)
> + goto out_mode_error;
> +
> + /* CONV_READ requires read to trigger first sample. */
> + struct i3c_priv_xfer t[2] = {
> + {
> + .data.out = &st->reg_addr_conv,
> + .len = sizeof(st->reg_addr_conv),
> + .rnw = false,
> + },
> + {
> + .data.in = &st->buf.be32,
> + .len = sizeof(st->buf.be32),
> + .rnw = true,
> + }
> + };
> +
> + ret = i3c_device_do_priv_xfers(st->i3cdev, t, st->gpo_irq[1] ? 2 : 1);
> + if (ret)
> + goto out_mode_error;
> + return 0;
> +
> +out_mode_error:
> + pm_runtime_put_autosuspend(&st->i3cdev->dev);
> +
> + return ret;
I guess with ACQUIRE() this function will look better, because the explicit
reference count bumping (with an associated comment) is more descriptive on
what's going on here with PM. Same for other related functions.
> +}
...
> if (ret)
> return dev_err_probe(dev, ret, "Failed to request i3c ibi\n");
>
> + INIT_WORK(&st->trig_conv, ad4062_trigger_work);
This is mixture of devm_*() and non-devm_*() calls. How did you (stress) test
the removal and error paths here? Wouldn't devm-helpers.h APIs help here to
make / keep order correct?
> return devm_iio_device_register(dev, indio_dev);
--
With Best Regards,
Andy Shevchenko
On Mon, Nov 24, 2025 at 11:36:12AM +0200, Andy Shevchenko wrote:
> On Mon, Nov 24, 2025 at 10:18:04AM +0100, Jorge Marques wrote:
Hi Andy,
> > Adds support for IIO Trigger. Optionally, gp1 is assigned as Data Ready
> > signal, if not present, fallback to an I3C IBI with the same role.
> > The software trigger is allocated by the device, but must be attached by
> > the user before enabling the buffer. The purpose is to not impede
> > removing the driver due to the increased reference count when
> > iio_trigger_set_immutable or iio_trigger_get is used.
>
> We refer to the functions as func(). Mind the parentheses.
>
> ...
>
Ack.
> > + struct ad4062_state *st = container_of(work, struct ad4062_state,
> > + trig_conv);
>
> I think the
>
> struct ad4062_state *st =
> container_of(work, struct ad4062_state, trig_conv);
>
> reads better.
>
Ack.
> > + int ret;
>
> ...
>
> > + /* Read current conversion, if at reg CONV_READ, stop bit triggers
> > + * next sample and does not need writing the address.
> > + */
>
> /*
> * The multi-line comment style is as in
> * this example. Please, check and update.
> */
>
Ack.
> > +static irqreturn_t ad4062_poll_handler(int irq, void *p)
> > +{
> > + struct iio_poll_func *pf = p;
> > + struct iio_dev *indio_dev = pf->indio_dev;
> > + struct ad4062_state *st = iio_priv(indio_dev);
> > +
> > + iio_trigger_notify_done(indio_dev->trig);
> > + schedule_work(&st->trig_conv);
> > +
> > + return IRQ_HANDLED;
> > }
>
> ...
>
> > +static int ad4062_triggered_buffer_postenable(struct iio_dev *indio_dev)
> > +{
> > + struct ad4062_state *st = iio_priv(indio_dev);
> > + int ret;
> > +
> > + ret = pm_runtime_resume_and_get(&st->i3cdev->dev);
> > + if (ret)
> > + return ret;
> > +
> > + ret = ad4062_set_operation_mode(st, st->mode);
> > + if (ret)
> > + goto out_mode_error;
> > +
> > + /* CONV_READ requires read to trigger first sample. */
> > + struct i3c_priv_xfer t[2] = {
> > + {
> > + .data.out = &st->reg_addr_conv,
> > + .len = sizeof(st->reg_addr_conv),
> > + .rnw = false,
> > + },
> > + {
> > + .data.in = &st->buf.be32,
> > + .len = sizeof(st->buf.be32),
> > + .rnw = true,
> > + }
> > + };
> > +
> > + ret = i3c_device_do_priv_xfers(st->i3cdev, t, st->gpo_irq[1] ? 2 : 1);
> > + if (ret)
> > + goto out_mode_error;
> > + return 0;
> > +
> > +out_mode_error:
> > + pm_runtime_put_autosuspend(&st->i3cdev->dev);
> > +
> > + return ret;
>
> I guess with ACQUIRE() this function will look better, because the explicit
> reference count bumping (with an associated comment) is more descriptive on
> what's going on here with PM. Same for other related functions.
>
Oh this one slipped through my fingers, should be using ACQUIRE as well, thanks
> > +}
>
> ...
>
> > if (ret)
> > return dev_err_probe(dev, ret, "Failed to request i3c ibi\n");
> >
> > + INIT_WORK(&st->trig_conv, ad4062_trigger_work);
>
> This is mixture of devm_*() and non-devm_*() calls. How did you (stress) test
> the removal and error paths here? Wouldn't devm-helpers.h APIs help here to
> make / keep order correct?
>
Oh yeah, missed this helper
ret = devm_work_autocancel(dev, &st->trig_conv, ad4062_trigger_work);
if (ret)
return ret;
the path was missing clean-up, and did cause issue if there was work
being done on detach
ERROR: iio:device0: Unable to get next block: Connection timed out (110)
8<--- cut here ---
Unable to handle kernel paging request at virtual address bf00715c when execute
[bf00715c] *pgd=0b43f811, *pte=00000000, *ppte=00000000
Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
Modules linked in: ad4062 regmap_i3c nvmem_axi_sysid [last unloaded: adi_i3c_master]
CPU: 0 UID: 0 PID: 8033 Comm: kworker/0:6 Not tainted 6.12.0+ #4
Hardware name: Xilinx Zynq Platform
Workqueue: events ad4062_trigger_work [ad4062]
PC is at 0xbf00715c
LR is at wait_for_completion_timeout+0xf0/0x118
pc : [<bf00715c>] lr : [<c07ec920>] psr: 60000013
sp : e0911ec0 ip : 00000000 fp : dfb960e0
r10: 00000011 r9 : 00000001 r8 : c4b89d40
r7 : c49e4500 r6 : c49da040 r5 : 00000001 r4 : e0911ef4
r3 : cb455500 r2 : 00000000 r1 : 00000000 r0 : 00000000
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
thanks,
Best regards,
Jorge
> > return devm_iio_device_register(dev, indio_dev);
>
> --
> With Best Regards,
> Andy Shevchenko
>
>
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