3 files changed, 271 insertions, 0 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 03791a6de349..492758120338 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -54,4 +54,10 @@ config AT91_ADC
         help
           Say yes here to build support for Atmel AT91 ADC.
 
+config LP8788_ADC
+        bool "LP8788 ADC driver"
+        depends on MFD_LP8788
+        help
+          Say yes here to build support for TI LP8788 ADC.
+
 endmenu
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 9824a70f4fd8..900995d5e179 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_AD7266) += ad7266.o
 obj-$(CONFIG_AD7476) += ad7476.o
 obj-$(CONFIG_AD7791) += ad7791.o
 obj-$(CONFIG_AT91_ADC) += at91_adc.o
+obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
diff --git a/drivers/iio/adc/lp8788_adc.c b/drivers/iio/adc/lp8788_adc.c
new file mode 100644
index 000000000000..a93aaf0bb841
--- /dev/null
+++ b/drivers/iio/adc/lp8788_adc.c
@@ -0,0 +1,264 @@
+/*
+ * 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 = IIO_CHAN_INFO_RAW_SEPARATE_BIT |   \
+                        IIO_CHAN_INFO_SCALE_SEPARATE_BIT,       \
+                .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(adc->lp->dev, "iio map err: %d\n", ret);
+                return ret;
+        }
+
+        adc->map = map;
+        return 0;
+}
+
+static inline void lp8788_iio_map_unregister(struct iio_dev *indio_dev,
+                                struct lp8788_adc *adc)
+{
+        iio_map_array_unregister(indio_dev, adc->map);
+}
+
+static int __devinit 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 = iio_device_alloc(sizeof(*adc));
+        if (!indio_dev)
+                return -ENOMEM;
+
+        adc = iio_priv(indio_dev);
+        adc->lp = lp;
+        platform_set_drvdata(pdev, indio_dev);
+
+        ret = lp8788_iio_map_register(indio_dev, lp->pdata, adc);
+        if (ret)
+                goto err_iio_map;
+
+        mutex_init(&adc->lock);
+
+        indio_dev->dev.parent = lp->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(lp->dev, "iio dev register err: %d\n", ret);
+                goto err_iio_device;
+        }
+
+        return 0;
+
+err_iio_device:
+        lp8788_iio_map_unregister(indio_dev, adc);
+err_iio_map:
+        iio_device_free(indio_dev);
+        return ret;
+}
+
+static int __devexit lp8788_adc_remove(struct platform_device *pdev)
+{
+        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+        struct lp8788_adc *adc = iio_priv(indio_dev);
+
+        iio_device_unregister(indio_dev);
+        lp8788_iio_map_unregister(indio_dev, adc);
+        iio_device_free(indio_dev);
+
+        return 0;
+}
+
+static struct platform_driver lp8788_adc_driver = {
+        .probe = lp8788_adc_probe,
+        .remove = __devexit_p(lp8788_adc_remove),
+        .driver = {
+                .name = LP8788_DEV_ADC,
+                .owner = THIS_MODULE,
+        },
+};
+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");