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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/iio/adc/ltc2497-core.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/iio/adc/ltc2497-core.c')
-rw-r--r--drivers/iio/adc/ltc2497-core.c246
1 files changed, 246 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..f52d37af4
--- /dev/null
+++ b/drivers/iio/adc/ltc2497-core.c
@@ -0,0 +1,246 @@
+// 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+ * so the last reading is still not outdated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 = ddata->chip_info->resolution + 1;
+
+ 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;
+
+ /*
+ * Keep using dev_name() for the iio_dev's name on some of the parts,
+ * since updating it would result in a ABI breakage.
+ */
+ if (ddata->chip_info->name)
+ indio_dev->name = ddata->chip_info->name;
+ else
+ 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");