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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-01-10 10:44:00 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-01-10 10:44:00 +0100
commit821f7ce79fd1ef2bf96a1b93521d8800abd24a1f (patch)
treed17f9fd1ade5c3e0a70a1ab8ae04964b1290dcf5 /drivers/iio/adc/ltc2496.c
parent0469fc6a1a8715b5c09117a26700da0d67061fb5 (diff)
parentc1d1c4a62db5c4745b9e15cfee0daf0f774f73fc (diff)
Merge tag 'iio-for-5.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes: First set of new device support, features and cleanups for IIO in the 5.6 cycle New device support * ad7091r5 ADC - New driver with follow up patch adding scale and vref support. - DT bindings * ad7923 - Support for ad7908, ad7918 and ad7928 added to driver. * bma180 - Support the BMA254 accelerometer. Required fairly substantial rework to allow for small differences between this an existing parts. * bma400 accelerometer - New driver with follow up patch for regulator support. - DT bindings. * asc dlhl60d - New driver support this range of pressure and temperature sensors. - DT bindings. * ltc2496 ADC - New driver to support this ADC. - Split the existing LTC2497 driver generic component out and reuse. - DT bindings. * parallax ping - New driver supporting ultrasonic and laser tof distance sensors. - Bindings for these sensors. New features * core - New char type for read_raw returns, used for thermocouple types. - Rename read_first_n callback to read. The reasons behind the original naming are lost to the mists of time. * ad799x - Allow pm_ops to disable device completely allowing regulator power down. * bma180 - Enable basic regulator support. * dmaengine buffer - Report platform data alignment requirements via new ABI. * max31856 - Add option to set mains filter rejection frequency and document new in_temp_filter_notch_center_frequency ABI. - Add support for configuring HW averaging (oversampling ratio) - Add runtime configuration of thermocouple type and document new ABI. * maxim-thermocouple - Add read only access to thermocouple type using new ABI, includes adding more specific compatibles to reflect which variant of the chip is being used. * mpu6050 - Provide option to support the PMU9150 in package magnetometer directly rather than via auxiliary bus. * stm32_adc - Add overrun interrupt checks to detect if this happens. * st_lsm6dsx - Enable the sensor-hub support for lsm6dsm. Includes various reworks to allow this. Cleanups and minor fixes * Subsystem wide - Tidy up indentation in Kconfig and fix alphabetical order of AD7091R5. - Drop linux/gpio.h and linux/of_gpio.h from drivers that don't use them. * ad7266 - Convert to GPIO descriptors. * ad7303 - Avoid a dance with checking if the regulator is supplied by just using the optional request interface. * ad7887 - Simplify channel specification assignment to enable adding more devices. * ad7923 - Drop some unused and largely pointless defines of BOB_N==N variety. - Tidy up checkpatch warnings. - Add missing of_device_id table. * adf4350 - Convert to GPIO descriptors. * ak8975 - Convert to GPIO descriptors. * ADIS library and drivers - Expand scope of txrx_lock to cover all state and rename as state_lock - Add unlocked read / write to allow grouping of consecutive calls under single lock / unlock. - Add unlocked check_status, reset to allow grouping under single lock / unlock. - Remove remaining uses of core mlock for local state protection. mlock should never be used directly as it protects tightly defined core IIO device management state. * adis16240 - Enforce only supported SPI mode on driver load + add DT binding doc. * atlas-ph-sensor - Rename to atlas-sensor given it now covers things beyond ph sensors. * bma180 - Use local dev variable to tidy up code. - Use c99 style explicity .member assignment to make driver more readable. * bmp280 - Drop ACPI support. No evidence this was used and appropriate ID is not registered. - Allow ACPI to bind device via PRP0001 * dmaengine buffer - Use dma_request_chan instead of dma_request_slave_channel_reason as that ABI is going away. - Add module info to avoid tainting the kernel. * hts221 - Avoid magic number defines when only used to fill structure elements that are self describing. * lm3533 - Drop a stray semicolon. * max9611 - Cleanup enum handling to be more resilient to future changes. * mpu6050 - Delete MPU9150 from supported SPI devices as doesn't provide SPI. - Select I2C_MUX again after kbuild issue fixed elsewhere. * stm32-timer - Drop an unnecessary register update. * ssp_sensors - Convert to GPIO descriptors. * st_sensors - drop !CONFIG_ACPI defines as ACPI_PTR() will stop them being used anyway. - Make default platform data structures __maybe_unsued. - Fill in some missing kernel-doc function parameters. * st_lsm6dsx - white space fixes. - Mark some constants that aren't always used as __maybe_unused. - Drop of ID table guards as they just pervent use under ACPI. - Switch to device properties to allow ACPI usage. * st_uvis25 - Drop acpi.h include as no ACPI APIs used. * ti-ads1015 - Drop legacy platform data as no one seems to be using it. - Use the device property API instead of OF specific. * ti-ads7950 - typo fix in error message. * tag 'iio-for-5.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (99 commits) iio: accel: bma180: BMA254 support iio: pressure: bmp280: Allow device to be enumerated from ACPI iio: pressure: bmp280: Drop ACPI support dt-bindings: iio: adc: convert sd modulator to json-schema iio: buffer: rename 'read_first_n' callback to 'read' iio: buffer-dmaengine: Report buffer length requirements bindings: iio: pressure: Add documentation for dlh driver dt-bindings: Add asc vendor iio: pressure: Add driver for DLH pressure sensors iio: buffer-dmaengine: Add module information iio: accel: bma180: Use explicit member assignment iio: accel: bma180: Basic regulator support iio: accel: bma180: Add dev helper variable iio: imu: st_lsm6dsx: enable sensor-hub support for lsm6dsm iio: imu: st_lsm6dsx: rename st_lsm6dsx_shub_read_reg in st_lsm6dsx_shub_read_output iio: imu: st_lsm6dsx: check if shub_output reg is located in primary page iio: imu: st_lsm6dsx: check if pull_up is located in primary page iio: imu: st_lsm6dsx: check if master_enable is located in primary page iio: imu: st_lsm6dsx: export max num of slave devices in st_lsm6dsx_shub_settings iio: light: remove unneeded semicolon ...
Diffstat (limited to 'drivers/iio/adc/ltc2496.c')
-rw-r--r--drivers/iio/adc/ltc2496.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/drivers/iio/adc/ltc2496.c b/drivers/iio/adc/ltc2496.c
new file mode 100644
index 000000000000..88a30156a849
--- /dev/null
+++ b/drivers/iio/adc/ltc2496.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ltc2496.c - Driver for Analog Devices/Linear Technology LTC2496 ADC
+ *
+ * Based on ltc2497.c which has
+ * Copyright (C) 2017 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ *
+ * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/2496fc.pdf
+ */
+
+#include <linux/spi/spi.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include "ltc2497.h"
+
+struct ltc2496_driverdata {
+ /* this must be the first member */
+ struct ltc2497core_driverdata common_ddata;
+ struct spi_device *spi;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ unsigned char rxbuf[3] ____cacheline_aligned;
+ unsigned char txbuf[3];
+};
+
+static int ltc2496_result_and_measure(struct ltc2497core_driverdata *ddata,
+ u8 address, int *val)
+{
+ struct ltc2496_driverdata *st =
+ container_of(ddata, struct ltc2496_driverdata, common_ddata);
+ struct spi_transfer t = {
+ .tx_buf = st->txbuf,
+ .rx_buf = st->rxbuf,
+ .len = sizeof(st->txbuf),
+ };
+ int ret;
+
+ st->txbuf[0] = LTC2497_ENABLE | address;
+
+ ret = spi_sync_transfer(st->spi, &t, 1);
+ if (ret < 0) {
+ dev_err(&st->spi->dev, "spi_sync_transfer failed: %pe\n",
+ ERR_PTR(ret));
+ return ret;
+ }
+
+ if (val)
+ *val = ((st->rxbuf[0] & 0x3f) << 12 |
+ st->rxbuf[1] << 4 | st->rxbuf[2] >> 4) -
+ (1 << 17);
+
+ return 0;
+}
+
+static int ltc2496_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct ltc2496_driverdata *st;
+ struct device *dev = &spi->dev;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ spi_set_drvdata(spi, indio_dev);
+ st->spi = spi;
+ st->common_ddata.result_and_measure = ltc2496_result_and_measure;
+
+ return ltc2497core_probe(dev, indio_dev);
+}
+
+static int ltc2496_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+ ltc2497core_remove(indio_dev);
+
+ return 0;
+}
+
+static const struct of_device_id ltc2496_of_match[] = {
+ { .compatible = "lltc,ltc2496", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ltc2496_of_match);
+
+static struct spi_driver ltc2496_driver = {
+ .driver = {
+ .name = "ltc2496",
+ .of_match_table = of_match_ptr(ltc2496_of_match),
+ },
+ .probe = ltc2496_probe,
+ .remove = ltc2496_remove,
+};
+module_spi_driver(ltc2496_driver);
+
+MODULE_AUTHOR("Uwe Kleine-König <u.kleine-könig@pengutronix.de>");
+MODULE_DESCRIPTION("Linear Technology LTC2496 ADC driver");
+MODULE_LICENSE("GPL v2");