--- /dev/null
+/*
+ * TI LP8788 MFD - ADC driver
+ *
+ * Copyright 2012 Texas Instruments
+ *
+ * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/iio/machine.h>
+#include <linux/mfd/lp8788.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* register address */
+#define LP8788_ADC_CONF 0x60
+#define LP8788_ADC_RAW 0x61
+#define LP8788_ADC_DONE 0x63
+
+#define ADC_CONV_START 1
+
+struct lp8788_adc {
+ struct lp8788 *lp;
+ struct iio_map *map;
+ struct mutex lock;
+};
+
+static const int lp8788_scale[LPADC_MAX] = {
+ [LPADC_VBATT_5P5] = 1343101,
+ [LPADC_VIN_CHG] = 3052503,
+ [LPADC_IBATT] = 610500,
+ [LPADC_IC_TEMP] = 61050,
+ [LPADC_VBATT_6P0] = 1465201,
+ [LPADC_VBATT_5P0] = 1221001,
+ [LPADC_ADC1] = 610500,
+ [LPADC_ADC2] = 610500,
+ [LPADC_VDD] = 1025641,
+ [LPADC_VCOIN] = 757020,
+ [LPADC_ADC3] = 610500,
+ [LPADC_ADC4] = 610500,
+};
+
+static int lp8788_get_adc_result(struct lp8788_adc *adc, enum lp8788_adc_id id,
+ int *val)
+{
+ unsigned int msb;
+ unsigned int lsb;
+ unsigned int result;
+ u8 data;
+ u8 rawdata[2];
+ int size = ARRAY_SIZE(rawdata);
+ int retry = 5;
+ int ret;
+
+ data = (id << 1) | ADC_CONV_START;
+ ret = lp8788_write_byte(adc->lp, LP8788_ADC_CONF, data);
+ if (ret)
+ goto err_io;
+
+ /* retry until adc conversion is done */
+ data = 0;
+ while (retry--) {
+ usleep_range(100, 200);
+
+ ret = lp8788_read_byte(adc->lp, LP8788_ADC_DONE, &data);
+ if (ret)
+ goto err_io;
+
+ /* conversion done */
+ if (data)
+ break;
+ }
+
+ ret = lp8788_read_multi_bytes(adc->lp, LP8788_ADC_RAW, rawdata, size);
+ if (ret)
+ goto err_io;
+
+ msb = (rawdata[0] << 4) & 0x00000ff0;
+ lsb = (rawdata[1] >> 4) & 0x0000000f;
+ result = msb | lsb;
+ *val = result;
+
+ return 0;
+
+err_io:
+ return ret;
+}
+
+static int lp8788_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct lp8788_adc *adc = iio_priv(indio_dev);
+ enum lp8788_adc_id id = chan->channel;
+ int ret;
+
+ mutex_lock(&adc->lock);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = lp8788_get_adc_result(adc, id, val) ? -EIO : IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ *val = lp8788_scale[id] / 1000000;
+ *val2 = lp8788_scale[id] % 1000000;
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ mutex_unlock(&adc->lock);
+
+ return ret;
+}
+
+static const struct iio_info lp8788_adc_info = {
+ .read_raw = &lp8788_adc_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+#define LP8788_CHAN(_id, _type) { \
+ .type = _type, \
+ .indexed = 1, \
+ .channel = LPADC_##_id, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .datasheet_name = #_id, \
+}
+
+static const struct iio_chan_spec lp8788_adc_channels[] = {
+ [LPADC_VBATT_5P5] = LP8788_CHAN(VBATT_5P5, IIO_VOLTAGE),
+ [LPADC_VIN_CHG] = LP8788_CHAN(VIN_CHG, IIO_VOLTAGE),
+ [LPADC_IBATT] = LP8788_CHAN(IBATT, IIO_CURRENT),
+ [LPADC_IC_TEMP] = LP8788_CHAN(IC_TEMP, IIO_TEMP),
+ [LPADC_VBATT_6P0] = LP8788_CHAN(VBATT_6P0, IIO_VOLTAGE),
+ [LPADC_VBATT_5P0] = LP8788_CHAN(VBATT_5P0, IIO_VOLTAGE),
+ [LPADC_ADC1] = LP8788_CHAN(ADC1, IIO_VOLTAGE),
+ [LPADC_ADC2] = LP8788_CHAN(ADC2, IIO_VOLTAGE),
+ [LPADC_VDD] = LP8788_CHAN(VDD, IIO_VOLTAGE),
+ [LPADC_VCOIN] = LP8788_CHAN(VCOIN, IIO_VOLTAGE),
+ [LPADC_ADC3] = LP8788_CHAN(ADC3, IIO_VOLTAGE),
+ [LPADC_ADC4] = LP8788_CHAN(ADC4, IIO_VOLTAGE),
+};
+
+/* default maps used by iio consumer (lp8788-charger driver) */
+static struct iio_map lp8788_default_iio_maps[] = {
+ {
+ .consumer_dev_name = "lp8788-charger",
+ .consumer_channel = "lp8788_vbatt_5p0",
+ .adc_channel_label = "VBATT_5P0",
+ },
+ {
+ .consumer_dev_name = "lp8788-charger",
+ .consumer_channel = "lp8788_adc1",
+ .adc_channel_label = "ADC1",
+ },
+ { }
+};
+
+static int lp8788_iio_map_register(struct iio_dev *indio_dev,
+ struct lp8788_platform_data *pdata,
+ struct lp8788_adc *adc)
+{
+ struct iio_map *map;
+ int ret;
+
+ map = (!pdata || !pdata->adc_pdata) ?
+ lp8788_default_iio_maps : pdata->adc_pdata;
+
+ ret = iio_map_array_register(indio_dev, map);
+ if (ret) {
+ dev_err(&indio_dev->dev, "iio map err: %d\n", ret);
+ return ret;
+ }
+
+ adc->map = map;
+ return 0;
+}
+
+static int lp8788_adc_probe(struct platform_device *pdev)
+{
+ struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
+ struct iio_dev *indio_dev;
+ struct lp8788_adc *adc;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ adc = iio_priv(indio_dev);
+ adc->lp = lp;
+ platform_set_drvdata(pdev, indio_dev);
+
+ indio_dev->dev.of_node = pdev->dev.of_node;
+ ret = lp8788_iio_map_register(indio_dev, lp->pdata, adc);
+ if (ret)
+ return ret;
+
+ mutex_init(&adc->lock);
+
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->name = pdev->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &lp8788_adc_info;
+ indio_dev->channels = lp8788_adc_channels;
+ indio_dev->num_channels = ARRAY_SIZE(lp8788_adc_channels);
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "iio dev register err: %d\n", ret);
+ goto err_iio_device;
+ }
+
+ return 0;
+
+err_iio_device:
+ iio_map_array_unregister(indio_dev);
+ return ret;
+}
+
+static int lp8788_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+ iio_device_unregister(indio_dev);
+ iio_map_array_unregister(indio_dev);
+
+ return 0;
+}
+
+static struct platform_driver lp8788_adc_driver = {
+ .probe = lp8788_adc_probe,
+ .remove = lp8788_adc_remove,
+ .driver = {
+ .name = LP8788_DEV_ADC,
+ },
+};
+module_platform_driver(lp8788_adc_driver);
+
+MODULE_DESCRIPTION("Texas Instruments LP8788 ADC Driver");
+MODULE_AUTHOR("Milo Kim");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:lp8788-adc");
Code Review / kvmfornfv.git / blobdiff