Re: [PATCH 2/5] lmp92001: mfd: iio: adc: Add support LMP92001

From: Jonathan Cameron
Date: Sun Sep 03 2017 - 12:58:19 EST


On Wed, 30 Aug 2017 20:21:58 +0100
Jonathan Cameron <jic23@xxxxxxxxxxxxxxxxxxxxx> wrote:

> Hi, for a multipart driver like this, please send all parts to all cc'd people.
> We would like to know how it fits together.
>
> Resending with that will save everyone time tracking down the other parts.

Just to clarify - I'm not going to even look at this until you resend
with all patches sent to all relevant lists and people. It would just
waste time. Others may also be waiting for this before taking a look
(or just busy ;)

Jonathan

>
> Jonathan.
>
> On 30 August 2017 19:14:09 BST, s.abhisit@xxxxxxxxx wrote:
> >From: Abhisit Sangjan <s.abhisit@xxxxxxxxx>
> >
> >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@xxxxxxxxx>
> >---
> > 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@xxxxxxxxx>
> >+ *
> >+ * 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@xxxxxxxxx>");
> >+MODULE_DESCRIPTION("IIO ADC interface for TI LMP92001");
> >+MODULE_LICENSE("GPL");
> >+MODULE_ALIAS("platform:lmp92001-adc");
>