lkml.org 
[lkml]   [2017]   [Aug]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/5] lmp92001: mfd: iio: adc: Add support LMP92001
Date
From: Abhisit Sangjan <s.abhisit@gmail.com>

TI LMP92001 Analog System Monitor and Controller

8-bit GPIOs.
12 DACs with 12-bit resolution.

The GPIOs and DACs are shared port function with Cy function pin to
take control the pin suddenly from external hardware.
DAC's referance voltage selectable for Internal/External.

16 + 1 ADCs with 12-bit resolution.

Built-in internal Temperature Sensor on channel 17.
Window Comparator Function is supported on channel 1-3 and 9-11 for
monitoring with interrupt signal (pending to implement for interrupt).
ADC's referance voltage selectable for Internal/External.

Signed-off-by: Abhisit Sangjan <s.abhisit@gmail.com>
---
drivers/iio/adc/Kconfig | 10 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/lmp92001-adc.c | 476 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 487 insertions(+)
create mode 100644 drivers/iio/adc/lmp92001-adc.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 614fa41559b1..2adeba543ac7 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -331,6 +331,16 @@ config IMX7D_ADC
This driver can also be built as a module. If so, the module will be
called imx7d_adc.

+config LMP92001_ADC
+ tristate "TI LMP92001 ADC Driver"
+ depends on MFD_LMP92001
+ help
+ If you say yes here you get support for TI LMP92001 ADCs
+ conversion.
+
+ This driver can also be built as a module. If so, the module will
+ be called lmp92001_adc.
+
config LP8788_ADC
tristate "LP8788 ADC driver"
depends on MFD_LP8788
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index b546736a5541..2ed89862090b 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_HI8435) += hi8435.o
obj-$(CONFIG_HX711) += hx711.o
obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
+obj-$(CONFIG_LMP92001_ADC) += lmp92001-adc.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o
obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o
diff --git a/drivers/iio/adc/lmp92001-adc.c b/drivers/iio/adc/lmp92001-adc.c
new file mode 100644
index 000000000000..f706a364337d
--- /dev/null
+++ b/drivers/iio/adc/lmp92001-adc.c
@@ -0,0 +1,476 @@
+/*
+ * lmp92001-adc.c - Support for TI LMP92001 ADCs
+ *
+ * Copyright 2016-2017 Celestica Ltd.
+ *
+ * Author: Abhisit Sangjan <s.abhisit@gmail.com>
+ *
+ * Inspired by wm831x and ad5064 drivers.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/iio/iio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/lmp92001/core.h>
+
+static int lmp92001_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel, int *val, int *val2, long mask)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int code, cgen, sgen, try;
+ int ret;
+
+ mutex_lock(&lmp92001->adc_lock);
+
+ ret = regmap_read(lmp92001->regmap, LMP92001_CGEN, &cgen);
+ if (ret < 0)
+ goto exit;
+
+ /*
+ * Is not continuous conversion?
+ * Lock the HW registers (if needed).
+ * Triggering single-short conversion.
+ * Waiting for conversion successful.
+ */
+ if (!(cgen & CGEN_STRT)) {
+ if (!(cgen & CGEN_LCK)) {
+ ret = regmap_update_bits(lmp92001->regmap,
+ LMP92001_CGEN, CGEN_LCK, CGEN_LCK);
+ if (ret < 0)
+ goto exit;
+ }
+
+ /* Writing any value to trigger Single-Shot conversion. */
+ ret = regmap_write(lmp92001->regmap, LMP92001_CTRIG, 1);
+ if (ret < 0)
+ goto exit;
+
+ /* In case of conversion is in-progress, repeat for 10 times. */
+ try = 10;
+ do {
+ ret = regmap_read(lmp92001->regmap,
+ LMP92001_SGEN, &sgen);
+ if (ret < 0)
+ goto exit;
+ } while ((sgen & CGEN_RST) && (--try > 0));
+
+ if (!try) {
+ ret = -ETIME;
+ goto exit;
+ }
+ }
+
+ ret = regmap_read(lmp92001->regmap, 0x1F + channel->channel, &code);
+ if (ret < 0)
+ goto exit;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (channel->type) {
+ case IIO_VOLTAGE:
+ case IIO_TEMP:
+ *val = code;
+ ret = IIO_VAL_INT;
+ goto exit;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ /* In case of no match channel info/type is return here. */
+ ret = -EINVAL;
+
+exit:
+ mutex_unlock(&lmp92001->adc_lock);
+
+ return ret;
+}
+
+static const struct iio_info lmp92001_info = {
+ .read_raw = lmp92001_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static ssize_t lmp92001_avref_read(struct iio_dev *indio_dev,
+ uintptr_t private, struct iio_chan_spec const *channel, char *buf)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int cref;
+ int ret;
+
+ ret = regmap_read(lmp92001->regmap, LMP92001_CREF, &cref);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%s\n", (cref & CREF_AEXT) ? "external" : "internal");
+}
+
+static ssize_t lmp92001_avref_write(struct iio_dev *indio_dev,
+ uintptr_t private, struct iio_chan_spec const *channel,
+ const char *buf, size_t len)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int cref;
+ int ret;
+
+ if (strncmp("external", buf, 8) == 0)
+ cref = 2;
+ else if (strncmp("internal", buf, 8) == 0)
+ cref = 0;
+ else
+ return -EINVAL;
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CREF, CREF_AEXT,
+ cref);
+ if (ret < 0)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lmp92001_enable_read(struct iio_dev *indio_dev,
+ uintptr_t private, struct iio_chan_spec const *channel, char *buf)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int reg, cad;
+ int ret;
+
+ switch (channel->channel) {
+ case 1 ... 8:
+ reg = LMP92001_CAD1;
+ break;
+ case 9 ... 16:
+ reg = LMP92001_CAD2;
+ break;
+ case 17:
+ reg = LMP92001_CAD3;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = regmap_read(lmp92001->regmap, reg, &cad);
+ if (ret < 0)
+ return ret;
+
+ if (channel->channel <= 8)
+ cad >>= channel->channel - 1;
+ else if (channel->channel > 8)
+ cad >>= channel->channel - 9;
+ else if (channel->channel > 16)
+ cad >>= channel->channel - 17;
+ else
+ return -EINVAL;
+
+ return sprintf(buf, "%s\n", cad & BIT(0) ? "enable" : "disable");
+}
+
+static ssize_t lmp92001_enable_write(struct iio_dev *indio_dev,
+ uintptr_t private, struct iio_chan_spec const *channel,
+ const char *buf, size_t len)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int reg, enable, shif, mask;
+ int ret;
+
+ switch (channel->channel) {
+ case 1 ... 8:
+ reg = LMP92001_CAD1;
+ shif = (channel->channel - 1);
+ break;
+ case 9 ... 16:
+ reg = LMP92001_CAD2;
+ shif = (channel->channel - 9);
+ break;
+ case 17:
+ reg = LMP92001_CAD3;
+ shif = (channel->channel - 17);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (strncmp("enable", buf, 6) == 0)
+ enable = 1;
+ else if (strncmp("disable", buf, 7) == 0)
+ enable = 0;
+ else
+ return -EINVAL;
+
+ enable <<= shif;
+ mask = 1 << shif;
+
+ ret = regmap_update_bits(lmp92001->regmap, reg, mask, enable);
+ if (ret < 0)
+ return ret;
+
+ return len;
+}
+
+static ssize_t lmp92001_mode_read(struct iio_dev *indio_dev,
+ uintptr_t private, struct iio_chan_spec const *channel, char *buf)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int cgen;
+ int ret;
+
+ ret = regmap_read(lmp92001->regmap, LMP92001_CGEN, &cgen);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%s\n",
+ cgen & BIT(0) ? "continuous" : "single-shot");
+}
+
+static ssize_t lmp92001_mode_write(struct iio_dev *indio_dev,
+ uintptr_t private, struct iio_chan_spec const *channel,
+ const char *buf, size_t len)
+{
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+ unsigned int cgen;
+ int ret;
+
+ if (strncmp("continuous", buf, 10) == 0)
+ cgen = 1;
+ else if (strncmp("single-shot", buf, 11) == 0)
+ cgen = 0;
+ else
+ return -EINVAL;
+
+ mutex_lock(&lmp92001->adc_lock);
+
+ /*
+ * Unlock the HW registers.
+ * Set conversion mode.
+ * Lock the HW registers.
+ */
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK, 0);
+ if (ret < 0)
+ goto exit;
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_STRT,
+ cgen);
+ if (ret < 0)
+ goto exit;
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK,
+ CGEN_LCK);
+ if (ret < 0)
+ goto exit;
+
+ return len;
+
+exit:
+ mutex_unlock(&lmp92001->adc_lock);
+
+ return ret;
+}
+
+static const struct iio_chan_spec_ext_info lmp92001_ext_info[] = {
+ {
+ .name = "vref",
+ .read = lmp92001_avref_read,
+ .write = lmp92001_avref_write,
+ .shared = IIO_SHARED_BY_ALL,
+ }, {
+ .name = "en",
+ .read = lmp92001_enable_read,
+ .write = lmp92001_enable_write,
+ .shared = IIO_SEPARATE,
+ }, {
+ .name = "mode",
+ .read = lmp92001_mode_read,
+ .write = lmp92001_mode_write,
+ .shared = IIO_SHARED_BY_ALL,
+ }, { },
+};
+
+static const struct iio_event_spec lmp92001_events[] = {
+ {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
+ BIT(IIO_EV_INFO_VALUE),
+ }, {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_FALLING,
+ .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
+ BIT(IIO_EV_INFO_VALUE),
+ }, { },
+};
+
+#define LMP92001_CHAN_SPEC(_ch, _type, _event, _nevent) \
+{ \
+ .channel = _ch, \
+ .type = _type, \
+ .indexed = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .event_spec = _event, \
+ .num_event_specs = _nevent, \
+ .ext_info = lmp92001_ext_info, \
+}
+
+static const struct iio_chan_spec lmp92001_adc_channels[] = {
+ LMP92001_CHAN_SPEC(1, IIO_VOLTAGE, lmp92001_events,
+ ARRAY_SIZE(lmp92001_events)),
+ LMP92001_CHAN_SPEC(2, IIO_VOLTAGE, lmp92001_events,
+ ARRAY_SIZE(lmp92001_events)),
+ LMP92001_CHAN_SPEC(3, IIO_VOLTAGE, lmp92001_events,
+ ARRAY_SIZE(lmp92001_events)),
+ LMP92001_CHAN_SPEC(4, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(5, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(6, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(7, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(8, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(9, IIO_VOLTAGE, lmp92001_events,
+ ARRAY_SIZE(lmp92001_events)),
+ LMP92001_CHAN_SPEC(10, IIO_VOLTAGE, lmp92001_events,
+ ARRAY_SIZE(lmp92001_events)),
+ LMP92001_CHAN_SPEC(11, IIO_VOLTAGE, lmp92001_events,
+ ARRAY_SIZE(lmp92001_events)),
+ LMP92001_CHAN_SPEC(12, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(13, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(14, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(15, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(16, IIO_VOLTAGE, NULL, 0),
+ LMP92001_CHAN_SPEC(17, IIO_TEMP, NULL, 0),
+};
+
+static int lmp92001_adc_probe(struct platform_device *pdev)
+{
+ struct lmp92001 *lmp92001 = dev_get_drvdata(pdev->dev.parent);
+ struct iio_dev *indio_dev;
+ struct device_node *np = pdev->dev.of_node;
+ unsigned int cgen = 0, cad1, cad2, cad3;
+ u32 mask;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, 0);
+ if (!indio_dev)
+ return -ENOMEM;
+
+ iio_device_set_drvdata(indio_dev, lmp92001);
+
+ mutex_init(&lmp92001->adc_lock);
+
+ indio_dev->name = pdev->name;
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &lmp92001_info;
+ indio_dev->channels = lmp92001_adc_channels;
+ indio_dev->num_channels = ARRAY_SIZE(lmp92001_adc_channels);
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CGEN,
+ CGEN_RST, CGEN_RST);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to self reset all registers\n");
+ return ret;
+ }
+
+ /*
+ * Turn on all of them, if you are pretty sure they are must be
+ * real-time update or specify which channel is needed to be used to
+ * save conversion time for a cycle.
+ */
+ ret = of_property_read_u32(np, "ti,lmp92001-adc-mask", &mask);
+ if (ret < 0) {
+ cad1 = cad2 = cad3 = 0xFF;
+ dev_info(&pdev->dev, "turn on all of channels by default\n");
+ } else {
+ cad1 = mask & 0xFF;
+ cad2 = (mask >> 8) & 0xFF;
+ cad3 = (mask >> 16) & 0xFF;
+ }
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD1, 0xFF, cad1);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable/disable channels 1-8\n");
+ return ret;
+ }
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD2, 0xFF, cad2);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable/disable channels 9-16\n");
+ return ret;
+ }
+
+ ret = regmap_update_bits(lmp92001->regmap, LMP92001_CAD3, BIT(0), cad3);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "failed to enable/disable channel 17 (temperature)\n");
+ return ret;
+ }
+
+ cgen |= 1; /* Continuous conversion is default. */
+
+ /* Lock the HW registers and set conversion mode. */
+ ret = regmap_update_bits(lmp92001->regmap,
+ LMP92001_CGEN, CGEN_LCK | CGEN_STRT,
+ cgen | CGEN_LCK);
+ if (ret < 0)
+ return ret;
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ return devm_iio_device_register(&pdev->dev, indio_dev);
+}
+
+static int lmp92001_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct lmp92001 *lmp92001 = iio_device_get_drvdata(indio_dev);
+
+ /*
+ * To stop ADC conversion to save power
+ *
+ * Unlock the HW registers.
+ * Set conversion mode to single-shot.
+ * Lock the HW registers.
+ */
+ regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK, 0);
+ regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_STRT, 0);
+ regmap_update_bits(lmp92001->regmap, LMP92001_CGEN, CGEN_LCK, CGEN_LCK);
+
+ return 0;
+}
+
+static struct platform_driver lmp92001_adc_driver = {
+ .driver.name = "lmp92001-adc",
+ .probe = lmp92001_adc_probe,
+ .remove = lmp92001_adc_remove,
+};
+
+static int __init lmp92001_adc_init(void)
+{
+ return platform_driver_register(&lmp92001_adc_driver);
+}
+subsys_initcall(lmp92001_adc_init);
+
+static void __exit lmp92001_adc_exit(void)
+{
+ platform_driver_unregister(&lmp92001_adc_driver);
+}
+module_exit(lmp92001_adc_exit);
+
+MODULE_AUTHOR("Abhisit Sangjan <s.abhisit@gmail.com>");
+MODULE_DESCRIPTION("IIO ADC interface for TI LMP92001");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:lmp92001-adc");
--
2.13.0
\
 
 \ /
  Last update: 2017-08-30 20:16    [W:0.077 / U:10.756 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site