On 12/09/14 13:44, Peter Meerwald wrote:
>
>> Platform driver for XPowers AXP288 ADC, which is a sub-device of the
>> customized PMIC for Intel Baytrail-CR platforms. GPADC device enumerates
>> as one of the MFD cell devices. It uses IIO infrastructure to communicate
>> with userspace and consumer drivers.
>>
>> Usages of ADC channels include battery charging and thermal sensors.
>
> minor nitpicking below
A few more bits and pieces from me.
Jonathan
>
>> Based on initial work by:
>> Ramakrishna Pallala <ramakrishna.pallala@xxxxxxxxx>
>>
>> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
>> ---
>> drivers/iio/adc/Kconfig | 8 ++
>> drivers/iio/adc/Makefile | 1 +
>> drivers/iio/adc/axp288_gpadc.c | 238 +++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 247 insertions(+)
>> create mode 100644 drivers/iio/adc/axp288_gpadc.c
>>
>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
>> index 11b048a..d02a08e 100644
>> --- a/drivers/iio/adc/Kconfig
>> +++ b/drivers/iio/adc/Kconfig
>> @@ -127,6 +127,14 @@ config AT91_ADC
>> help
>> Say yes here to build support for Atmel AT91 ADC.
>>
>> +config AXP288_GPADC
>> + tristate "X-Power AXP288 GPADC driver"
>> + depends on MFD_AXP2XX
>> + help
>> + Say yes here to have support for X-Power power management IC (PMIC) ADC
>> + device. Depending on platform configuration, this general purpose ADC can
>> + be used for sampling sensors such as thermal resistors.
>> +
>> config EXYNOS_ADC
>> tristate "Exynos ADC driver support"
>> depends on ARCH_EXYNOS || (OF && COMPILE_TEST)
>> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
>> index ad81b51..8bf0104 100644
>> --- a/drivers/iio/adc/Makefile
>> +++ b/drivers/iio/adc/Makefile
>> @@ -30,3 +30,4 @@ obj-$(CONFIG_VF610_ADC) += vf610_adc.o
>> obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o
>> xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o
>> obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o
>> +obj-$(CONFIG_AXP288_GPADC) += axp288_gpadc.o
>> diff --git a/drivers/iio/adc/axp288_gpadc.c b/drivers/iio/adc/axp288_gpadc.c
>> new file mode 100644
>> index 0000000..aaa24b0
>> --- /dev/null
>> +++ b/drivers/iio/adc/axp288_gpadc.c
>> @@ -0,0 +1,238 @@
>> +/*
>> + * axp288_gpadc.c - Xpower AXP288 PMIC GPADC Driver
>
> X-Power
>
>> + *
>> + * Copyright (C) 2014 Intel Corporation
>> + *
>> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> + *
>> + * 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; version 2 of the License.
>> + *
>> + * 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/module.h>
>> +#include <linux/kernel.h>
>> +#include <linux/device.h>
>> +#include <linux/regmap.h>
>> +#include <linux/mfd/axp2xx.h>
>> +#include <linux/platform_device.h>
>> +
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/machine.h>
>> +#include <linux/iio/driver.h>
>> +
>> +#define AXP288_ADC_EN_MASK 0xF1
>> +#define AXP288_ADC_TS_PIN_GPADC 0xF2
>> +#define AXP288_ADC_TS_PIN_ON 0xF3
>> +
>> +enum axp288_adc_id {
>> + AXP288_ADC_TS,
>> + AXP288_ADC_PMIC,
>> + AXP288_ADC_GP,
>> + AXP288_ADC_BATT_CHRG_I,
>> + AXP288_ADC_BATT_DISCHRG_I,
>> + AXP288_ADC_BATT_V,
>> + AXP288_ADC_NR_CHAN,
>> +};
>> +
>> +static const int axp288_scale[AXP288_ADC_NR_CHAN] = {
>
> axp288_adc_scale
>
>> + [AXP288_ADC_BATT_CHRG_I] = 1,
>> + [AXP288_ADC_BATT_DISCHRG_I] = 1,
>> + [AXP288_ADC_BATT_V] = 1,
>> +};
>> +
>> +struct gpadc_info {
>
> axp288_adc_info
>
>> + int irq;
>> + struct device *dev;
>> + struct regmap *regmap;
>> +};
>> +
>> +#define ADC_CHANNEL(_type, _channel, _address, _info_mask) \
>
> AXP288_ADC_CHANNEL
>
>> + { \
>> + .indexed = 1, \
>> + .type = _type, \
>> + .channel = _channel, \
>> + .address = _address, \
>> + .datasheet_name = "CH"#_channel, \
>> + .info_mask_separate = _info_mask, \
>> + }
I'm not entirely convinced this little macro actually helps seeing as
there is only one fixed element and a little saving on the datasheet name.
Would be tempted to just list it long hand below for simplicity.
>> +
>> +static const struct iio_chan_spec const axp288_adc_channels[] = {
>> + ADC_CHANNEL(IIO_TEMP, 0, AXP288_TS_ADC_H, 0),
>> + ADC_CHANNEL(IIO_TEMP, 1, AXP288_PMIC_ADC_H, 0),
>> + ADC_CHANNEL(IIO_TEMP, 2, AXP288_GP_ADC_H, 0),
So these first three have no known scale or offset? Fair enough if true.
>> + ADC_CHANNEL(IIO_CURRENT, 3, AXP20X_BATT_CHRG_I_H,
>> + (BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE))),
So the output of these (raw*scale) is in milliamps as per the ABI?
(it would be unusual if they are!)
>> + ADC_CHANNEL(IIO_CURRENT, 4, AXP20X_BATT_DISCHRG_I_H,
>> + (BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE))),
>> + ADC_CHANNEL(IIO_VOLTAGE, 5, AXP20X_BATT_V_H,
>> + (BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE))),
>> +};
>> +
>> +#define ADC_MAP(_adc_channel_label, \
>
> AXP288_ADC_MAP
>
>> + _consumer_dev_name, \
>> + _consumer_channel) \
>> + { \
>> + .adc_channel_label = _adc_channel_label, \
>> + .consumer_dev_name = _consumer_dev_name, \
>> + .consumer_channel = _consumer_channel, \
>> + }
>> +
>> +/* for consumer drivers */
>> +static struct iio_map axp288_iio_default_maps[] = {
>
> axp288_adc_iio_default_maps
>
>> + ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
>> + ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
>> + ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
>> + ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
>> + ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
>> + ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
>> + {},
>> +};
>> +
>> +static int axp288_adc_read_raw(struct iio_dev *indio_dev,
>> + struct iio_chan_spec const *chan,
>> + int *val, int *val2, long mask)
>> +{
>> + int ret;
>> + struct gpadc_info *info = iio_priv(indio_dev);
>> + unsigned int th, tl;
>> +
>> + mutex_lock(&indio_dev->mlock);
>> +
>> + switch (mask) {
>> + case IIO_CHAN_INFO_RAW:
>> + /* special case for GPADC sample */
>> + if (chan->address == AXP288_GP_ADC_H)
>> + regmap_write(info->regmap, AXP288_ADC_TS_PIN_CTRL,
>> + AXP288_ADC_TS_PIN_GPADC);
>> + ret = regmap_read(info->regmap, chan->address, &th);
>> + if (ret) {
>> + dev_err(&indio_dev->dev, "sample raw data high failed\n");
>> + break;
>> + }
>> + ret = regmap_read(info->regmap, chan->address + 1, &tl);
>> + if (ret) {
>> + dev_err(&indio_dev->dev, "sample raw data low failed\n");
>> + break;
>> + }
>> +
>> + *val = (th << 4) + ((tl >> 4) & 0x0F);
>> + ret = IIO_VAL_INT;
>> + break;
>> + case IIO_CHAN_INFO_SCALE:
>> + *val = axp288_scale[chan->channel];
>
> either set
> *val2 = 0 or
> ret = IIO_VAL_INT;
This one. No point in misleading userspace into thinking their might
be a decimal part sometimes. If they are as it appears all 1, then those
channels can use IIO_CHAN_INFO_PROCESSED and skip exporting this at all.
>
>> + ret = IIO_VAL_INT_PLUS_MICRO;
>> + break;
>> + default:
>> + ret = -EINVAL;
>> + }
>> +
>> + if (IIO_CHAN_INFO_RAW && chan->address == AXP288_GP_ADC_H)
Well, IIO_CHAN_INFO_RAW is always going to be false, so I'm guessing this
isn't what was intended...
mask == IIO_CHAN_INFO_RAW I would imagine.
>> + regmap_write(info->regmap, AXP288_ADC_TS_PIN_CTRL,
>> + AXP288_ADC_TS_PIN_ON);
>> +
>> + mutex_unlock(&indio_dev->mlock);
>> +
>> + return ret;
>> +}
>> +
>> +static int axp288_gpadc_enable(struct regmap *regmap, bool enable)
>
> axp288_adc_enable()
>
>> +{
>> + unsigned int pin_on, adc_en;
>> +
>> + if (enable) {
>> + pin_on = AXP288_ADC_TS_PIN_ON;
>> + adc_en = AXP288_ADC_EN_MASK;
>> + } else {
>> + pin_on = ~AXP288_ADC_TS_PIN_ON;
>> + adc_en = ~AXP288_ADC_EN_MASK;
>> + }
>> + if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, pin_on))
>> + return -EIO;
>> +
>> + return regmap_write(regmap, AXP20X_ADC_EN1, ~AXP288_ADC_EN_MASK);
>> +}
>> +
>> +static const struct iio_info axp288_iio_info = {
>
> axp288_adc_iio_info
or axp288_adc_info would do.
>
>> + .read_raw = &axp288_adc_read_raw,
>> + .driver_module = THIS_MODULE,
>> +};
>> +
>> +static int axp288_gpadc_probe(struct platform_device *pdev)
>
> axp288_adc_probe()
>
>> +{
>> + int err;
>> + struct gpadc_info *info;
>> + struct iio_dev *indio_dev;
>> + struct axp2xx_dev *axp2xx = dev_get_drvdata(pdev->dev.parent);
>> + int irq;
>> +
>> + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
>> + if (!indio_dev)
>> + return -ENOMEM;
>> +
>> + info = iio_priv(indio_dev);
>> + irq = platform_get_irq(pdev, 0);
>
> could save local irq variable and directly assign to info->irq
>
>> + if (irq < 0) {
>> + dev_err(&pdev->dev, "no irq resource?\n");
>> + return irq;
>> + }
>> + info->irq = irq;
>> + platform_set_drvdata(pdev, indio_dev);
>> + info->regmap = axp2xx->regmap;
>> + axp288_gpadc_enable(axp2xx->regmap, true);
>> +
>> + indio_dev->dev.parent = &pdev->dev;
>> + indio_dev->name = pdev->name;
>> + indio_dev->channels = axp288_adc_channels;
>> + indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
>> + indio_dev->info = &axp288_iio_info;
>> + indio_dev->modes = INDIO_DIRECT_MODE;
>> + /* REVISIT: override default map with platform data */
>> + err = iio_map_array_register(indio_dev, axp288_iio_default_maps);
>> + if (err)
>
> maybe err < 0, just to be consistent with below
>
>> + goto err_disable_dev;
>> +
>> + err = iio_device_register(indio_dev);
>> + if (err < 0) {
>> + dev_err(&pdev->dev, "unable to register iio device\n");
>> + goto err_array_unregister;
>> + }
>> + return 0;
>> +
>> +err_array_unregister:
>> + iio_map_array_unregister(indio_dev);
>> +err_disable_dev:
>> + axp288_gpadc_enable(axp2xx->regmap, false);
>> + return err;
>> +}
>> +
>> +static int axp288_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);
>
> axp288_gpadc_enable(axp2xx->regmap, false);
>
>> +
>> + return 0;
>> +}
>> +
>> +static struct platform_driver axp288_gpadc_driver = {
>> + .probe = axp288_gpadc_probe,
>> + .remove = axp288_gpadc_remove,
>> + .driver = {
>> + .name = "axp288_adc",
>> + .owner = THIS_MODULE,
>> + },
>> +};
>> +
>> +module_platform_driver(axp288_gpadc_driver);
>> +
>> +MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>");
>> +MODULE_DESCRIPTION("Dollar Cove Xpower AXP288 General Purpose ADC Driver");
>
> X-Power
>
>> +MODULE_LICENSE("GPL");
>>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
