1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/iio/trigger/stm32-lptimer-trigger.c b/drivers/iio/trigger/stm32-lptimer-trigger.c
new file mode 100644
index 000000000..98cdc7e47
--- /dev/null
+++ b/drivers/iio/trigger/stm32-lptimer-trigger.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * STM32 Low-Power Timer Trigger driver
+ *
+ * Copyright (C) STMicroelectronics 2017
+ *
+ * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
+ *
+ * Inspired by Benjamin Gaignard's stm32-timer-trigger driver
+ */
+
+#include <linux/iio/timer/stm32-lptim-trigger.h>
+#include <linux/mfd/stm32-lptimer.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+/* List Low-Power Timer triggers */
+static const char * const stm32_lptim_triggers[] = {
+	LPTIM1_OUT,
+	LPTIM2_OUT,
+	LPTIM3_OUT,
+};
+
+struct stm32_lptim_trigger {
+	struct device *dev;
+	const char *trg;
+};
+
+static int stm32_lptim_validate_device(struct iio_trigger *trig,
+				       struct iio_dev *indio_dev)
+{
+	if (indio_dev->modes & INDIO_HARDWARE_TRIGGERED)
+		return 0;
+
+	return -EINVAL;
+}
+
+static const struct iio_trigger_ops stm32_lptim_trigger_ops = {
+	.validate_device = stm32_lptim_validate_device,
+};
+
+/**
+ * is_stm32_lptim_trigger
+ * @trig: trigger to be checked
+ *
+ * return true if the trigger is a valid STM32 IIO Low-Power Timer Trigger
+ * either return false
+ */
+bool is_stm32_lptim_trigger(struct iio_trigger *trig)
+{
+	return (trig->ops == &stm32_lptim_trigger_ops);
+}
+EXPORT_SYMBOL(is_stm32_lptim_trigger);
+
+static int stm32_lptim_setup_trig(struct stm32_lptim_trigger *priv)
+{
+	struct iio_trigger *trig;
+
+	trig = devm_iio_trigger_alloc(priv->dev, "%s", priv->trg);
+	if  (!trig)
+		return -ENOMEM;
+
+	trig->dev.parent = priv->dev->parent;
+	trig->ops = &stm32_lptim_trigger_ops;
+	iio_trigger_set_drvdata(trig, priv);
+
+	return devm_iio_trigger_register(priv->dev, trig);
+}
+
+static int stm32_lptim_trigger_probe(struct platform_device *pdev)
+{
+	struct stm32_lptim_trigger *priv;
+	u32 index;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	if (of_property_read_u32(pdev->dev.of_node, "reg", &index))
+		return -EINVAL;
+
+	if (index >= ARRAY_SIZE(stm32_lptim_triggers))
+		return -EINVAL;
+
+	priv->dev = &pdev->dev;
+	priv->trg = stm32_lptim_triggers[index];
+
+	ret = stm32_lptim_setup_trig(priv);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+}
+
+static const struct of_device_id stm32_lptim_trig_of_match[] = {
+	{ .compatible = "st,stm32-lptimer-trigger", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, stm32_lptim_trig_of_match);
+
+static struct platform_driver stm32_lptim_trigger_driver = {
+	.probe = stm32_lptim_trigger_probe,
+	.driver = {
+		.name = "stm32-lptimer-trigger",
+		.of_match_table = stm32_lptim_trig_of_match,
+	},
+};
+module_platform_driver(stm32_lptim_trigger_driver);
+
+MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
+MODULE_ALIAS("platform:stm32-lptimer-trigger");
+MODULE_DESCRIPTION("STMicroelectronics STM32 LPTIM trigger driver");
+MODULE_LICENSE("GPL v2");