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Diffstat (limited to 'drivers/iio/trigger/stm32-lptimer-trigger.c')
-rw-r--r--drivers/iio/trigger/stm32-lptimer-trigger.c118
1 files changed, 118 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..2e447a3f0
--- /dev/null
+++ b/drivers/iio/trigger/stm32-lptimer-trigger.c
@@ -0,0 +1,118 @@
+// 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/mod_devicetable.h>
+#include <linux/module.h>
+#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,
+};
+
+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 (device_property_read_u32(&pdev->dev, "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");