linux/drivers/iio/adc/da9150-gpadc.c
Adam Thomson ed5f07b3d3 iio: Add support for DA9150 GPADC
This patch adds support for DA9150 Charger & Fuel-Gauge IC GPADC.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-02-25 21:05:26 +01:00

407 lines
10 KiB
C

/*
* DA9150 GPADC Driver
*
* Copyright (c) 2014 Dialog Semiconductor
*
* Author: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/completion.h>
#include <linux/iio/iio.h>
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>
#include <linux/mfd/da9150/core.h>
#include <linux/mfd/da9150/registers.h>
/* Channels */
enum da9150_gpadc_hw_channel {
DA9150_GPADC_HW_CHAN_GPIOA_2V = 0,
DA9150_GPADC_HW_CHAN_GPIOA_2V_,
DA9150_GPADC_HW_CHAN_GPIOB_2V,
DA9150_GPADC_HW_CHAN_GPIOB_2V_,
DA9150_GPADC_HW_CHAN_GPIOC_2V,
DA9150_GPADC_HW_CHAN_GPIOC_2V_,
DA9150_GPADC_HW_CHAN_GPIOD_2V,
DA9150_GPADC_HW_CHAN_GPIOD_2V_,
DA9150_GPADC_HW_CHAN_IBUS_SENSE,
DA9150_GPADC_HW_CHAN_IBUS_SENSE_,
DA9150_GPADC_HW_CHAN_VBUS_DIV,
DA9150_GPADC_HW_CHAN_VBUS_DIV_,
DA9150_GPADC_HW_CHAN_ID,
DA9150_GPADC_HW_CHAN_ID_,
DA9150_GPADC_HW_CHAN_VSYS,
DA9150_GPADC_HW_CHAN_VSYS_,
DA9150_GPADC_HW_CHAN_GPIOA_6V,
DA9150_GPADC_HW_CHAN_GPIOA_6V_,
DA9150_GPADC_HW_CHAN_GPIOB_6V,
DA9150_GPADC_HW_CHAN_GPIOB_6V_,
DA9150_GPADC_HW_CHAN_GPIOC_6V,
DA9150_GPADC_HW_CHAN_GPIOC_6V_,
DA9150_GPADC_HW_CHAN_GPIOD_6V,
DA9150_GPADC_HW_CHAN_GPIOD_6V_,
DA9150_GPADC_HW_CHAN_VBAT,
DA9150_GPADC_HW_CHAN_VBAT_,
DA9150_GPADC_HW_CHAN_TBAT,
DA9150_GPADC_HW_CHAN_TBAT_,
DA9150_GPADC_HW_CHAN_TJUNC_CORE,
DA9150_GPADC_HW_CHAN_TJUNC_CORE_,
DA9150_GPADC_HW_CHAN_TJUNC_OVP,
DA9150_GPADC_HW_CHAN_TJUNC_OVP_,
};
enum da9150_gpadc_channel {
DA9150_GPADC_CHAN_GPIOA = 0,
DA9150_GPADC_CHAN_GPIOB,
DA9150_GPADC_CHAN_GPIOC,
DA9150_GPADC_CHAN_GPIOD,
DA9150_GPADC_CHAN_IBUS,
DA9150_GPADC_CHAN_VBUS,
DA9150_GPADC_CHAN_VSYS,
DA9150_GPADC_CHAN_VBAT,
DA9150_GPADC_CHAN_TBAT,
DA9150_GPADC_CHAN_TJUNC_CORE,
DA9150_GPADC_CHAN_TJUNC_OVP,
};
/* Private data */
struct da9150_gpadc {
struct da9150 *da9150;
struct device *dev;
struct mutex lock;
struct completion complete;
};
static irqreturn_t da9150_gpadc_irq(int irq, void *data)
{
struct da9150_gpadc *gpadc = data;
complete(&gpadc->complete);
return IRQ_HANDLED;
}
static int da9150_gpadc_read_adc(struct da9150_gpadc *gpadc, int hw_chan)
{
u8 result_regs[2];
int result;
mutex_lock(&gpadc->lock);
/* Set channel & enable measurement */
da9150_reg_write(gpadc->da9150, DA9150_GPADC_MAN,
(DA9150_GPADC_EN_MASK |
hw_chan << DA9150_GPADC_MUX_SHIFT));
/* Consume left-over completion from a previous timeout */
try_wait_for_completion(&gpadc->complete);
/* Check for actual completion */
wait_for_completion_timeout(&gpadc->complete, msecs_to_jiffies(5));
/* Read result and status from device */
da9150_bulk_read(gpadc->da9150, DA9150_GPADC_RES_A, 2, result_regs);
mutex_unlock(&gpadc->lock);
/* Check to make sure device really has completed reading */
if (result_regs[1] & DA9150_GPADC_RUN_MASK) {
dev_err(gpadc->dev, "Timeout on channel %d of GPADC\n",
hw_chan);
return -ETIMEDOUT;
}
/* LSBs - 2 bits */
result = (result_regs[1] & DA9150_GPADC_RES_L_MASK) >>
DA9150_GPADC_RES_L_SHIFT;
/* MSBs - 8 bits */
result |= result_regs[0] << DA9150_GPADC_RES_L_BITS;
return result;
}
static inline int da9150_gpadc_gpio_6v_voltage_now(int raw_val)
{
/* Convert to mV */
return (6 * ((raw_val * 1000) + 500)) / 1024;
}
static inline int da9150_gpadc_ibus_current_avg(int raw_val)
{
/* Convert to mA */
return (4 * ((raw_val * 1000) + 500)) / 2048;
}
static inline int da9150_gpadc_vbus_21v_voltage_now(int raw_val)
{
/* Convert to mV */
return (21 * ((raw_val * 1000) + 500)) / 1024;
}
static inline int da9150_gpadc_vsys_6v_voltage_now(int raw_val)
{
/* Convert to mV */
return (3 * ((raw_val * 1000) + 500)) / 512;
}
static int da9150_gpadc_read_processed(struct da9150_gpadc *gpadc, int channel,
int hw_chan, int *val)
{
int raw_val;
raw_val = da9150_gpadc_read_adc(gpadc, hw_chan);
if (raw_val < 0)
return raw_val;
switch (channel) {
case DA9150_GPADC_CHAN_GPIOA:
case DA9150_GPADC_CHAN_GPIOB:
case DA9150_GPADC_CHAN_GPIOC:
case DA9150_GPADC_CHAN_GPIOD:
*val = da9150_gpadc_gpio_6v_voltage_now(raw_val);
break;
case DA9150_GPADC_CHAN_IBUS:
*val = da9150_gpadc_ibus_current_avg(raw_val);
break;
case DA9150_GPADC_CHAN_VBUS:
*val = da9150_gpadc_vbus_21v_voltage_now(raw_val);
break;
case DA9150_GPADC_CHAN_VSYS:
*val = da9150_gpadc_vsys_6v_voltage_now(raw_val);
break;
default:
/* No processing for other channels so return raw value */
*val = raw_val;
break;
}
return IIO_VAL_INT;
}
static int da9150_gpadc_read_scale(int channel, int *val, int *val2)
{
switch (channel) {
case DA9150_GPADC_CHAN_VBAT:
*val = 2932;
*val2 = 1000;
return IIO_VAL_FRACTIONAL;
case DA9150_GPADC_CHAN_TJUNC_CORE:
case DA9150_GPADC_CHAN_TJUNC_OVP:
*val = 1000000;
*val2 = 4420;
return IIO_VAL_FRACTIONAL;
default:
return -EINVAL;
}
}
static int da9150_gpadc_read_offset(int channel, int *val)
{
switch (channel) {
case DA9150_GPADC_CHAN_VBAT:
*val = 1500000 / 2932;
return IIO_VAL_INT;
case DA9150_GPADC_CHAN_TJUNC_CORE:
case DA9150_GPADC_CHAN_TJUNC_OVP:
*val = -144;
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
static int da9150_gpadc_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct da9150_gpadc *gpadc = iio_priv(indio_dev);
if ((chan->channel < DA9150_GPADC_CHAN_GPIOA) ||
(chan->channel > DA9150_GPADC_CHAN_TJUNC_OVP))
return -EINVAL;
switch (mask) {
case IIO_CHAN_INFO_RAW:
case IIO_CHAN_INFO_PROCESSED:
return da9150_gpadc_read_processed(gpadc, chan->channel,
chan->address, val);
case IIO_CHAN_INFO_SCALE:
return da9150_gpadc_read_scale(chan->channel, val, val2);
case IIO_CHAN_INFO_OFFSET:
return da9150_gpadc_read_offset(chan->channel, val);
default:
return -EINVAL;
}
}
static const struct iio_info da9150_gpadc_info = {
.read_raw = &da9150_gpadc_read_raw,
.driver_module = THIS_MODULE,
};
#define DA9150_GPADC_CHANNEL(_id, _hw_id, _type, chan_info, \
_ext_name) { \
.type = _type, \
.indexed = 1, \
.channel = DA9150_GPADC_CHAN_##_id, \
.address = DA9150_GPADC_HW_CHAN_##_hw_id, \
.info_mask_separate = chan_info, \
.extend_name = _ext_name, \
.datasheet_name = #_id, \
}
#define DA9150_GPADC_CHANNEL_RAW(_id, _hw_id, _type, _ext_name) \
DA9150_GPADC_CHANNEL(_id, _hw_id, _type, \
BIT(IIO_CHAN_INFO_RAW), _ext_name)
#define DA9150_GPADC_CHANNEL_SCALED(_id, _hw_id, _type, _ext_name) \
DA9150_GPADC_CHANNEL(_id, _hw_id, _type, \
BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OFFSET), \
_ext_name)
#define DA9150_GPADC_CHANNEL_PROCESSED(_id, _hw_id, _type, _ext_name) \
DA9150_GPADC_CHANNEL(_id, _hw_id, _type, \
BIT(IIO_CHAN_INFO_PROCESSED), _ext_name)
/* Supported channels */
static const struct iio_chan_spec da9150_gpadc_channels[] = {
DA9150_GPADC_CHANNEL_PROCESSED(GPIOA, GPIOA_6V, IIO_VOLTAGE, NULL),
DA9150_GPADC_CHANNEL_PROCESSED(GPIOB, GPIOB_6V, IIO_VOLTAGE, NULL),
DA9150_GPADC_CHANNEL_PROCESSED(GPIOC, GPIOC_6V, IIO_VOLTAGE, NULL),
DA9150_GPADC_CHANNEL_PROCESSED(GPIOD, GPIOD_6V, IIO_VOLTAGE, NULL),
DA9150_GPADC_CHANNEL_PROCESSED(IBUS, IBUS_SENSE, IIO_CURRENT, "ibus"),
DA9150_GPADC_CHANNEL_PROCESSED(VBUS, VBUS_DIV_, IIO_VOLTAGE, "vbus"),
DA9150_GPADC_CHANNEL_PROCESSED(VSYS, VSYS, IIO_VOLTAGE, "vsys"),
DA9150_GPADC_CHANNEL_SCALED(VBAT, VBAT, IIO_VOLTAGE, "vbat"),
DA9150_GPADC_CHANNEL_RAW(TBAT, TBAT, IIO_VOLTAGE, "tbat"),
DA9150_GPADC_CHANNEL_SCALED(TJUNC_CORE, TJUNC_CORE, IIO_TEMP,
"tjunc_core"),
DA9150_GPADC_CHANNEL_SCALED(TJUNC_OVP, TJUNC_OVP, IIO_TEMP,
"tjunc_ovp"),
};
/* Default maps used by da9150-charger */
static struct iio_map da9150_gpadc_default_maps[] = {
{
.consumer_dev_name = "da9150-charger",
.consumer_channel = "CHAN_IBUS",
.adc_channel_label = "IBUS",
},
{
.consumer_dev_name = "da9150-charger",
.consumer_channel = "CHAN_VBUS",
.adc_channel_label = "VBUS",
},
{
.consumer_dev_name = "da9150-charger",
.consumer_channel = "CHAN_TJUNC",
.adc_channel_label = "TJUNC_CORE",
},
{
.consumer_dev_name = "da9150-charger",
.consumer_channel = "CHAN_VBAT",
.adc_channel_label = "VBAT",
},
{},
};
static int da9150_gpadc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct da9150 *da9150 = dev_get_drvdata(dev->parent);
struct da9150_gpadc *gpadc;
struct iio_dev *indio_dev;
int irq, ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*gpadc));
if (!indio_dev) {
dev_err(&pdev->dev, "Failed to allocate IIO device\n");
return -ENOMEM;
}
gpadc = iio_priv(indio_dev);
platform_set_drvdata(pdev, indio_dev);
gpadc->da9150 = da9150;
gpadc->dev = dev;
mutex_init(&gpadc->lock);
init_completion(&gpadc->complete);
irq = platform_get_irq_byname(pdev, "GPADC");
if (irq < 0) {
dev_err(dev, "Failed to get IRQ: %d\n", irq);
return irq;
}
ret = devm_request_threaded_irq(dev, irq, NULL, da9150_gpadc_irq,
IRQF_ONESHOT, "GPADC", gpadc);
if (ret) {
dev_err(dev, "Failed to request IRQ %d: %d\n", irq, ret);
return ret;
}
ret = iio_map_array_register(indio_dev, da9150_gpadc_default_maps);
if (ret) {
dev_err(dev, "Failed to register IIO maps: %d\n", ret);
return ret;
}
indio_dev->name = dev_name(dev);
indio_dev->dev.parent = dev;
indio_dev->dev.of_node = pdev->dev.of_node;
indio_dev->info = &da9150_gpadc_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = da9150_gpadc_channels;
indio_dev->num_channels = ARRAY_SIZE(da9150_gpadc_channels);
ret = iio_device_register(indio_dev);
if (ret) {
dev_err(dev, "Failed to register IIO device: %d\n", ret);
goto iio_map_unreg;
}
return 0;
iio_map_unreg:
iio_map_array_unregister(indio_dev);
return ret;
}
static int da9150_gpadc_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 da9150_gpadc_driver = {
.driver = {
.name = "da9150-gpadc",
},
.probe = da9150_gpadc_probe,
.remove = da9150_gpadc_remove,
};
module_platform_driver(da9150_gpadc_driver);
MODULE_DESCRIPTION("GPADC Driver for DA9150");
MODULE_AUTHOR("Adam Thomson <Adam.Thomson.Opensource@diasemi.com>");
MODULE_LICENSE("GPL");