[PATCH v4 3/8] iio: trigger: stm32-lptimer: add support for stm32mp25

From: Fabrice Gasnier
Date: Fri Mar 14 2025 - 13:36:31 EST


From: Olivier Moysan <olivier.moysan@xxxxxxxxxxx>

Add support for STM32MP25 SoC. Use newly introduced compatible to handle
this new HW variant. Add new trigger definitions that can be used by the
stm32 analog-to-digital converter. Use compatible data to identify them.

Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxxxxxxx>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
---
Changes in v4:
- Jonathan's comment: simplify infrastructure by keeping
devm_iio_trigger_register. Don't need to cast compatible data.
---
drivers/iio/trigger/stm32-lptimer-trigger.c | 75 ++++++++++++++-----
include/linux/iio/timer/stm32-lptim-trigger.h | 9 +++
2 files changed, 67 insertions(+), 17 deletions(-)

diff --git a/drivers/iio/trigger/stm32-lptimer-trigger.c b/drivers/iio/trigger/stm32-lptimer-trigger.c
index f1e18913236a..3dcc8d2fe093 100644
--- a/drivers/iio/trigger/stm32-lptimer-trigger.c
+++ b/drivers/iio/trigger/stm32-lptimer-trigger.c
@@ -16,16 +16,43 @@
#include <linux/platform_device.h>
#include <linux/property.h>

-/* List Low-Power Timer triggers */
-static const char * const stm32_lptim_triggers[] = {
- LPTIM1_OUT,
- LPTIM2_OUT,
- LPTIM3_OUT,
+/* Maximum triggers + one trailing null entry to indicate the end of array */
+#define MAX_TRIGGERS 3
+
+struct stm32_lptim_cfg {
+ const char * const (*triggers)[MAX_TRIGGERS];
+ unsigned int nb_triggers;
+};
+
+/* List Low-Power Timer triggers for H7, MP13, MP15 */
+static const char * const stm32_lptim_triggers[][MAX_TRIGGERS] = {
+ { LPTIM1_OUT,},
+ { LPTIM2_OUT,},
+ { LPTIM3_OUT,},
+};
+
+/* List Low-Power Timer triggers for STM32MP25 */
+static const char * const stm32mp25_lptim_triggers[][MAX_TRIGGERS] = {
+ { LPTIM1_CH1, LPTIM1_CH2, },
+ { LPTIM2_CH1, LPTIM2_CH2, },
+ { LPTIM3_CH1,},
+ { LPTIM4_CH1,},
+ { LPTIM5_OUT,},
+};
+
+static const struct stm32_lptim_cfg stm32mp15_lptim_cfg = {
+ .triggers = stm32_lptim_triggers,
+ .nb_triggers = ARRAY_SIZE(stm32_lptim_triggers),
+};
+
+static const struct stm32_lptim_cfg stm32mp25_lptim_cfg = {
+ .triggers = stm32mp25_lptim_triggers,
+ .nb_triggers = ARRAY_SIZE(stm32mp25_lptim_triggers),
};

struct stm32_lptim_trigger {
struct device *dev;
- const char *trg;
+ const char * const *triggers;
};

static int stm32_lptim_validate_device(struct iio_trigger *trig,
@@ -56,22 +83,33 @@ EXPORT_SYMBOL(is_stm32_lptim_trigger);

static int stm32_lptim_setup_trig(struct stm32_lptim_trigger *priv)
{
- struct iio_trigger *trig;
+ const char * const *cur = priv->triggers;
+ int ret;

- trig = devm_iio_trigger_alloc(priv->dev, "%s", priv->trg);
- if (!trig)
- return -ENOMEM;
+ while (cur && *cur) {
+ struct iio_trigger *trig;

- trig->dev.parent = priv->dev->parent;
- trig->ops = &stm32_lptim_trigger_ops;
- iio_trigger_set_drvdata(trig, priv);
+ trig = devm_iio_trigger_alloc(priv->dev, "%s", *cur);
+ if (!trig)
+ return -ENOMEM;

- return devm_iio_trigger_register(priv->dev, trig);
+ trig->dev.parent = priv->dev->parent;
+ trig->ops = &stm32_lptim_trigger_ops;
+ iio_trigger_set_drvdata(trig, priv);
+
+ ret = devm_iio_trigger_register(priv->dev, trig);
+ if (ret)
+ return ret;
+ cur++;
+ }
+
+ return 0;
}

static int stm32_lptim_trigger_probe(struct platform_device *pdev)
{
struct stm32_lptim_trigger *priv;
+ struct stm32_lptim_cfg const *lptim_cfg;
u32 index;

priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
@@ -81,17 +119,20 @@ static int stm32_lptim_trigger_probe(struct platform_device *pdev)
if (device_property_read_u32(&pdev->dev, "reg", &index))
return -EINVAL;

- if (index >= ARRAY_SIZE(stm32_lptim_triggers))
+ lptim_cfg = device_get_match_data(&pdev->dev);
+
+ if (index >= lptim_cfg->nb_triggers)
return -EINVAL;

priv->dev = &pdev->dev;
- priv->trg = stm32_lptim_triggers[index];
+ priv->triggers = lptim_cfg->triggers[index];

return stm32_lptim_setup_trig(priv);
}

static const struct of_device_id stm32_lptim_trig_of_match[] = {
- { .compatible = "st,stm32-lptimer-trigger", },
+ { .compatible = "st,stm32-lptimer-trigger", .data = &stm32mp15_lptim_cfg },
+ { .compatible = "st,stm32mp25-lptimer-trigger", .data = &stm32mp25_lptim_cfg},
{},
};
MODULE_DEVICE_TABLE(of, stm32_lptim_trig_of_match);
diff --git a/include/linux/iio/timer/stm32-lptim-trigger.h b/include/linux/iio/timer/stm32-lptim-trigger.h
index a34dcf6a6001..ce3cf0addb2e 100644
--- a/include/linux/iio/timer/stm32-lptim-trigger.h
+++ b/include/linux/iio/timer/stm32-lptim-trigger.h
@@ -14,6 +14,15 @@
#define LPTIM1_OUT "lptim1_out"
#define LPTIM2_OUT "lptim2_out"
#define LPTIM3_OUT "lptim3_out"
+#define LPTIM4_OUT "lptim4_out"
+#define LPTIM5_OUT "lptim5_out"
+
+#define LPTIM1_CH1 "lptim1_ch1"
+#define LPTIM1_CH2 "lptim1_ch2"
+#define LPTIM2_CH1 "lptim2_ch1"
+#define LPTIM2_CH2 "lptim2_ch2"
+#define LPTIM3_CH1 "lptim3_ch1"
+#define LPTIM4_CH1 "lptim4_ch1"

#if IS_REACHABLE(CONFIG_IIO_STM32_LPTIMER_TRIGGER)
bool is_stm32_lptim_trigger(struct iio_trigger *trig);
--
2.25.1