v4.19.13 snapshot.
diff --git a/drivers/iio/humidity/hts221_buffer.c b/drivers/iio/humidity/hts221_buffer.c
new file mode 100644
index 0000000..1a94b0b
--- /dev/null
+++ b/drivers/iio/humidity/hts221_buffer.c
@@ -0,0 +1,205 @@
+/*
+ * STMicroelectronics hts221 sensor driver
+ *
+ * Copyright 2016 STMicroelectronics Inc.
+ *
+ * Lorenzo Bianconi <lorenzo.bianconi@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/regmap.h>
+#include <linux/bitfield.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/events.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/buffer.h>
+
+#include <linux/platform_data/st_sensors_pdata.h>
+
+#include "hts221.h"
+
+#define HTS221_REG_DRDY_HL_ADDR 0x22
+#define HTS221_REG_DRDY_HL_MASK BIT(7)
+#define HTS221_REG_DRDY_PP_OD_ADDR 0x22
+#define HTS221_REG_DRDY_PP_OD_MASK BIT(6)
+#define HTS221_REG_DRDY_EN_ADDR 0x22
+#define HTS221_REG_DRDY_EN_MASK BIT(2)
+#define HTS221_REG_STATUS_ADDR 0x27
+#define HTS221_RH_DRDY_MASK BIT(1)
+#define HTS221_TEMP_DRDY_MASK BIT(0)
+
+static int hts221_trig_set_state(struct iio_trigger *trig, bool state)
+{
+ struct iio_dev *iio_dev = iio_trigger_get_drvdata(trig);
+ struct hts221_hw *hw = iio_priv(iio_dev);
+
+ return regmap_update_bits(hw->regmap, HTS221_REG_DRDY_EN_ADDR,
+ HTS221_REG_DRDY_EN_MASK,
+ FIELD_PREP(HTS221_REG_DRDY_EN_MASK, state));
+}
+
+static const struct iio_trigger_ops hts221_trigger_ops = {
+ .set_trigger_state = hts221_trig_set_state,
+};
+
+static irqreturn_t hts221_trigger_handler_thread(int irq, void *private)
+{
+ struct hts221_hw *hw = private;
+ int err, status;
+
+ err = regmap_read(hw->regmap, HTS221_REG_STATUS_ADDR, &status);
+ if (err < 0)
+ return IRQ_HANDLED;
+
+ /*
+ * H_DA bit (humidity data available) is routed to DRDY line.
+ * Humidity sample is computed after temperature one.
+ * Here we can assume data channels are both available if H_DA bit
+ * is set in status register
+ */
+ if (!(status & HTS221_RH_DRDY_MASK))
+ return IRQ_NONE;
+
+ iio_trigger_poll_chained(hw->trig);
+
+ return IRQ_HANDLED;
+}
+
+int hts221_allocate_trigger(struct hts221_hw *hw)
+{
+ struct iio_dev *iio_dev = iio_priv_to_dev(hw);
+ bool irq_active_low = false, open_drain = false;
+ struct device_node *np = hw->dev->of_node;
+ struct st_sensors_platform_data *pdata;
+ unsigned long irq_type;
+ int err;
+
+ irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq));
+
+ switch (irq_type) {
+ case IRQF_TRIGGER_HIGH:
+ case IRQF_TRIGGER_RISING:
+ break;
+ case IRQF_TRIGGER_LOW:
+ case IRQF_TRIGGER_FALLING:
+ irq_active_low = true;
+ break;
+ default:
+ dev_info(hw->dev,
+ "mode %lx unsupported, using IRQF_TRIGGER_RISING\n",
+ irq_type);
+ irq_type = IRQF_TRIGGER_RISING;
+ break;
+ }
+
+ err = regmap_update_bits(hw->regmap, HTS221_REG_DRDY_HL_ADDR,
+ HTS221_REG_DRDY_HL_MASK,
+ FIELD_PREP(HTS221_REG_DRDY_HL_MASK,
+ irq_active_low));
+ if (err < 0)
+ return err;
+
+ pdata = (struct st_sensors_platform_data *)hw->dev->platform_data;
+ if ((np && of_property_read_bool(np, "drive-open-drain")) ||
+ (pdata && pdata->open_drain)) {
+ irq_type |= IRQF_SHARED;
+ open_drain = true;
+ }
+
+ err = regmap_update_bits(hw->regmap, HTS221_REG_DRDY_PP_OD_ADDR,
+ HTS221_REG_DRDY_PP_OD_MASK,
+ FIELD_PREP(HTS221_REG_DRDY_PP_OD_MASK,
+ open_drain));
+ if (err < 0)
+ return err;
+
+ err = devm_request_threaded_irq(hw->dev, hw->irq, NULL,
+ hts221_trigger_handler_thread,
+ irq_type | IRQF_ONESHOT,
+ hw->name, hw);
+ if (err) {
+ dev_err(hw->dev, "failed to request trigger irq %d\n",
+ hw->irq);
+ return err;
+ }
+
+ hw->trig = devm_iio_trigger_alloc(hw->dev, "%s-trigger",
+ iio_dev->name);
+ if (!hw->trig)
+ return -ENOMEM;
+
+ iio_trigger_set_drvdata(hw->trig, iio_dev);
+ hw->trig->ops = &hts221_trigger_ops;
+ hw->trig->dev.parent = hw->dev;
+ iio_dev->trig = iio_trigger_get(hw->trig);
+
+ return devm_iio_trigger_register(hw->dev, hw->trig);
+}
+
+static int hts221_buffer_preenable(struct iio_dev *iio_dev)
+{
+ return hts221_set_enable(iio_priv(iio_dev), true);
+}
+
+static int hts221_buffer_postdisable(struct iio_dev *iio_dev)
+{
+ return hts221_set_enable(iio_priv(iio_dev), false);
+}
+
+static const struct iio_buffer_setup_ops hts221_buffer_ops = {
+ .preenable = hts221_buffer_preenable,
+ .postenable = iio_triggered_buffer_postenable,
+ .predisable = iio_triggered_buffer_predisable,
+ .postdisable = hts221_buffer_postdisable,
+};
+
+static irqreturn_t hts221_buffer_handler_thread(int irq, void *p)
+{
+ u8 buffer[ALIGN(2 * HTS221_DATA_SIZE, sizeof(s64)) + sizeof(s64)];
+ struct iio_poll_func *pf = p;
+ struct iio_dev *iio_dev = pf->indio_dev;
+ struct hts221_hw *hw = iio_priv(iio_dev);
+ struct iio_chan_spec const *ch;
+ int err;
+
+ /* humidity data */
+ ch = &iio_dev->channels[HTS221_SENSOR_H];
+ err = regmap_bulk_read(hw->regmap, ch->address,
+ buffer, HTS221_DATA_SIZE);
+ if (err < 0)
+ goto out;
+
+ /* temperature data */
+ ch = &iio_dev->channels[HTS221_SENSOR_T];
+ err = regmap_bulk_read(hw->regmap, ch->address,
+ buffer + HTS221_DATA_SIZE, HTS221_DATA_SIZE);
+ if (err < 0)
+ goto out;
+
+ iio_push_to_buffers_with_timestamp(iio_dev, buffer,
+ iio_get_time_ns(iio_dev));
+
+out:
+ iio_trigger_notify_done(hw->trig);
+
+ return IRQ_HANDLED;
+}
+
+int hts221_allocate_buffers(struct hts221_hw *hw)
+{
+ return devm_iio_triggered_buffer_setup(hw->dev, iio_priv_to_dev(hw),
+ NULL, hts221_buffer_handler_thread,
+ &hts221_buffer_ops);
+}
+
+MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics hts221 buffer driver");
+MODULE_LICENSE("GPL v2");