Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 238 insertions, 0 deletions

diff --git a/drivers/iio/adc/ltc2497-core.c b/drivers/iio/adc/ltc2497-core.c
new file mode 100644
index 000000000..2a485c8a1
--- /dev/null
+++ b/drivers/iio/adc/ltc2497-core.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ltc2497-core.c - Common code for Analog Devices/Linear Technology
+ * LTC2496 and LTC2497 ADCs
+ *
+ * Copyright (C) 2017 Analog Devices Inc.
+ */
+
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+
+#include "ltc2497.h"
+
+#define LTC2497_SGL			BIT(4)
+#define LTC2497_DIFF			0
+#define LTC2497_SIGN			BIT(3)
+
+static int ltc2497core_wait_conv(struct ltc2497core_driverdata *ddata)
+{
+	s64 time_elapsed;
+
+	time_elapsed = ktime_ms_delta(ktime_get(), ddata->time_prev);
+
+	if (time_elapsed < LTC2497_CONVERSION_TIME_MS) {
+		/* delay if conversion time not passed
+		 * since last read or write
+		 */
+		if (msleep_interruptible(
+		    LTC2497_CONVERSION_TIME_MS - time_elapsed))
+			return -ERESTARTSYS;
+
+		return 0;
+	}
+
+	if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) {
+		/* We're in automatic mode -
+		 * so the last reading is still not outdated
+		 */
+		return 0;
+	}
+
+	return 1;
+}
+
+static int ltc2497core_read(struct ltc2497core_driverdata *ddata, u8 address, int *val)
+{
+	int ret;
+
+	ret = ltc2497core_wait_conv(ddata);
+	if (ret < 0)
+		return ret;
+
+	if (ret || ddata->addr_prev != address) {
+		ret = ddata->result_and_measure(ddata, address, NULL);
+		if (ret < 0)
+			return ret;
+		ddata->addr_prev = address;
+
+		if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS))
+			return -ERESTARTSYS;
+	}
+
+	ret = ddata->result_and_measure(ddata, address, val);
+	if (ret < 0)
+		return ret;
+
+	ddata->time_prev = ktime_get();
+
+	return ret;
+}
+
+static int ltc2497core_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct ltc2497core_driverdata *ddata = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&indio_dev->mlock);
+		ret = ltc2497core_read(ddata, chan->address, val);
+		mutex_unlock(&indio_dev->mlock);
+		if (ret < 0)
+			return ret;
+
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		ret = regulator_get_voltage(ddata->ref);
+		if (ret < 0)
+			return ret;
+
+		*val = ret / 1000;
+		*val2 = 17;
+
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+#define LTC2497_CHAN(_chan, _addr, _ds_name) { \
+	.type = IIO_VOLTAGE, \
+	.indexed = 1, \
+	.channel = (_chan), \
+	.address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC2497_SIGN : 0)), \
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+	.datasheet_name = (_ds_name), \
+}
+
+#define LTC2497_CHAN_DIFF(_chan, _addr) { \
+	.type = IIO_VOLTAGE, \
+	.indexed = 1, \
+	.channel = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 1 : 0), \
+	.channel2 = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 0 : 1),\
+	.address = (_addr | _chan), \
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+	.differential = 1, \
+}
+
+static const struct iio_chan_spec ltc2497core_channel[] = {
+	LTC2497_CHAN(0, LTC2497_SGL, "CH0"),
+	LTC2497_CHAN(1, LTC2497_SGL, "CH1"),
+	LTC2497_CHAN(2, LTC2497_SGL, "CH2"),
+	LTC2497_CHAN(3, LTC2497_SGL, "CH3"),
+	LTC2497_CHAN(4, LTC2497_SGL, "CH4"),
+	LTC2497_CHAN(5, LTC2497_SGL, "CH5"),
+	LTC2497_CHAN(6, LTC2497_SGL, "CH6"),
+	LTC2497_CHAN(7, LTC2497_SGL, "CH7"),
+	LTC2497_CHAN(8, LTC2497_SGL, "CH8"),
+	LTC2497_CHAN(9, LTC2497_SGL, "CH9"),
+	LTC2497_CHAN(10, LTC2497_SGL, "CH10"),
+	LTC2497_CHAN(11, LTC2497_SGL, "CH11"),
+	LTC2497_CHAN(12, LTC2497_SGL, "CH12"),
+	LTC2497_CHAN(13, LTC2497_SGL, "CH13"),
+	LTC2497_CHAN(14, LTC2497_SGL, "CH14"),
+	LTC2497_CHAN(15, LTC2497_SGL, "CH15"),
+	LTC2497_CHAN_DIFF(0, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(1, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(2, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(3, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(4, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(5, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(6, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(7, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(0, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(1, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(2, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(3, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(4, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(5, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(6, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(7, LTC2497_DIFF | LTC2497_SIGN),
+};
+
+static const struct iio_info ltc2497core_info = {
+	.read_raw = ltc2497core_read_raw,
+};
+
+int ltc2497core_probe(struct device *dev, struct iio_dev *indio_dev)
+{
+	struct ltc2497core_driverdata *ddata = iio_priv(indio_dev);
+	int ret;
+
+	indio_dev->name = dev_name(dev);
+	indio_dev->info = &ltc2497core_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = ltc2497core_channel;
+	indio_dev->num_channels = ARRAY_SIZE(ltc2497core_channel);
+
+	ret = ddata->result_and_measure(ddata, LTC2497_CONFIG_DEFAULT, NULL);
+	if (ret < 0)
+		return ret;
+
+	ddata->ref = devm_regulator_get(dev, "vref");
+	if (IS_ERR(ddata->ref))
+		return dev_err_probe(dev, PTR_ERR(ddata->ref),
+				     "Failed to get vref regulator\n");
+
+	ret = regulator_enable(ddata->ref);
+	if (ret < 0) {
+		dev_err(dev, "Failed to enable vref regulator: %pe\n",
+			ERR_PTR(ret));
+		return ret;
+	}
+
+	if (dev->platform_data) {
+		struct iio_map *plat_data;
+
+		plat_data = (struct iio_map *)dev->platform_data;
+
+		ret = iio_map_array_register(indio_dev, plat_data);
+		if (ret) {
+			dev_err(&indio_dev->dev, "iio map err: %d\n", ret);
+			goto err_regulator_disable;
+		}
+	}
+
+	ddata->addr_prev = LTC2497_CONFIG_DEFAULT;
+	ddata->time_prev = ktime_get();
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0)
+		goto err_array_unregister;
+
+	return 0;
+
+err_array_unregister:
+	iio_map_array_unregister(indio_dev);
+
+err_regulator_disable:
+	regulator_disable(ddata->ref);
+
+	return ret;
+}
+EXPORT_SYMBOL_NS(ltc2497core_probe, LTC2497);
+
+void ltc2497core_remove(struct iio_dev *indio_dev)
+{
+	struct ltc2497core_driverdata *ddata = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	iio_map_array_unregister(indio_dev);
+
+	regulator_disable(ddata->ref);
+}
+EXPORT_SYMBOL_NS(ltc2497core_remove, LTC2497);
+
+MODULE_DESCRIPTION("common code for LTC2496/LTC2497 drivers");
+MODULE_LICENSE("GPL v2");