Should move to drivers/hwmon once people are happy with it. Minimal support of simple in, curr and temp attributes so far. Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxx> --- drivers/iio/Kconfig | 8 ++ drivers/iio/Makefile | 1 + drivers/iio/iio_hwmon.c | 227 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 236 insertions(+), 0 deletions(-) diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig index 308bc97..c2f0970 100644 --- a/drivers/iio/Kconfig +++ b/drivers/iio/Kconfig @@ -11,6 +11,14 @@ menuconfig IIO if IIO +config IIO_HWMON + tristate "Hwmon driver that uses channels specified via iio maps" + depends on HWMON + help + This is a platform driver that in combination with a suitable + map allows IIO devices to provide basic hwmon functionality + for those channels specified in the map. + source "drivers/iio/adc/Kconfig" source "drivers/iio/imu/Kconfig" source "drivers/iio/light/Kconfig" diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile index cfb588a..5f9c01a 100644 --- a/drivers/iio/Makefile +++ b/drivers/iio/Makefile @@ -6,6 +6,7 @@ obj-y = inkern.o obj-$(CONFIG_IIO) += iio.o industrialio-y := core.o +obj-$(CONFIG_IIO_HWMON) += iio_hwmon.o obj-y += adc/ obj-y += imu/ obj-y += light/ diff --git a/drivers/iio/iio_hwmon.c b/drivers/iio/iio_hwmon.c new file mode 100644 index 0000000..b3348ad --- /dev/null +++ b/drivers/iio/iio_hwmon.c @@ -0,0 +1,227 @@ +/* Hwmon client for industrial I/O devices + * + * Copyright (c) 2011 Jonathan Cameron + * + * 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. + * + * Limited functionality currently supported. + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/iio/inkern.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +/** + * struct iio_hwmon_state - device instance state + * @channels: filled with null terminated array of channels from iio + * @num_channels: number of channels in channels (saves counting twice) + * @hwmon_dev: associated hwmon device + * @attr_group: the group of attributes + * @attrs: null terminated array of attribute pointers. + */ +struct iio_hwmon_state { + struct iio_channel **channels; + int num_channels; + struct device *hwmon_dev; + struct attribute_group attr_group; + struct attribute **attrs; +}; + +/* + * Assumes that IIO and hwmon operate in the same base units. + * This is supposed to be true, but needs verification for + * new channel types. + */ +static ssize_t iio_hwmon_read_val(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + long result; + int val, ret, scaleint, scalepart; + struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr); + struct iio_hwmon_state *state = dev_get_drvdata(dev); + + /* + * No locking between this pair, so theoretically possible + * the scale has changed. + */ + ret = iio_read_channel_raw(state->channels[sattr->index], + &val); + if (ret < 0) + return ret; + + ret = iio_read_channel_scale(state->channels[sattr->index], + &scaleint, &scalepart); + if (ret < 0) + return ret; + switch (ret) { + case IIO_VAL_INT: + result = val * scaleint; + break; + case IIO_VAL_INT_PLUS_MICRO: + result = (long)val * (long)scaleint + + (long)val * (long)scalepart / 1000000L; + break; + case IIO_VAL_INT_PLUS_NANO: + result = (long)val * (long)scaleint + + (long)val * (long)scalepart / 1000000000L; + break; + default: + return -EINVAL; + } + return sprintf(buf, "%ld\n", result); +} + +static void iio_hwmon_free_attrs(struct iio_hwmon_state *st) +{ + int i; + struct sensor_device_attribute *a; + for (i = 0; i < st->num_channels; i++) + if (st->attrs[i]) { + a = to_sensor_dev_attr( + container_of(st->attrs[i], + struct device_attribute, + attr)); + kfree(a); + } +} + +static int __devinit iio_hwmon_probe(struct platform_device *pdev) +{ + struct iio_hwmon_state *st; + struct sensor_device_attribute *a; + int ret, i; + int in_i = 1, temp_i = 1, curr_i = 1; + + st = kzalloc(sizeof(*st), GFP_KERNEL); + if (st == NULL) { + ret = -ENOMEM; + goto error_ret; + } + + st->channels = iio_channel_get_all(&pdev->dev, NULL); + if (IS_ERR(st->channels)) { + ret = PTR_ERR(st->channels); + goto error_free_state; + } + + /* count how many attributes we have */ + while (st->channels[st->num_channels]) + st->num_channels++; + + st->attrs = kzalloc(sizeof(st->attrs) * (st->num_channels + 1), + GFP_KERNEL); + if (st->attrs == NULL) { + ret = -ENOMEM; + goto error_release_channels; + } + for (i = 0; i < st->num_channels; i++) { + a = kzalloc(sizeof(*a), GFP_KERNEL); + if (a == NULL) { + ret = -ENOMEM; + goto error_free_attrs; + } + + sysfs_attr_init(&a->dev_attr.attr); + switch (iio_get_channel_type(st->channels[i])) { + case IIO_VOLTAGE: + a->dev_attr.attr.name = kasprintf(GFP_KERNEL, + "in%d_input", + in_i++); + break; + case IIO_TEMP: + a->dev_attr.attr.name = kasprintf(GFP_KERNEL, + "temp%d_input", + temp_i++); + break; + case IIO_CURRENT: + a->dev_attr.attr.name = kasprintf(GFP_KERNEL, + "curr%d_input", + curr_i++); + break; + default: + ret = -EINVAL; + kfree(a); + goto error_free_attrs; + } + if (a->dev_attr.attr.name == NULL) { + kfree(a); + ret = -ENOMEM; + goto error_free_attrs; + } + a->dev_attr.show = iio_hwmon_read_val; + a->dev_attr.attr.mode = S_IRUGO; + a->index = i; + st->attrs[i] = &a->dev_attr.attr; + } + + st->attr_group.attrs = st->attrs; + platform_set_drvdata(pdev, st); + ret = sysfs_create_group(&pdev->dev.kobj, &st->attr_group); + if (ret < 0) + goto error_free_attrs; + + st->hwmon_dev = hwmon_device_register(&pdev->dev); + if (IS_ERR(st->hwmon_dev)) { + ret = PTR_ERR(st->hwmon_dev); + goto error_remove_group; + } + return 0; + +error_remove_group: + sysfs_remove_group(&pdev->dev.kobj, &st->attr_group); +error_free_attrs: + iio_hwmon_free_attrs(st); + kfree(st->attrs); +error_release_channels: + iio_channel_release_all(st->channels); +error_free_state: + kfree(st); +error_ret: + return ret; +} + +static int __devexit iio_hwmon_remove(struct platform_device *pdev) +{ + struct iio_hwmon_state *st = platform_get_drvdata(pdev); + + hwmon_device_unregister(st->hwmon_dev); + sysfs_remove_group(&pdev->dev.kobj, &st->attr_group); + iio_hwmon_free_attrs(st); + kfree(st->attrs); + iio_channel_release_all(st->channels); + + return 0; +} + +static struct platform_driver __refdata iio_hwmon_driver = { + .driver = { + .name = "iio_hwmon", + .owner = THIS_MODULE, + }, + .probe = iio_hwmon_probe, + .remove = __devexit_p(iio_hwmon_remove), +}; + +static int iio_inkern_init(void) +{ + return platform_driver_register(&iio_hwmon_driver); +} +module_init(iio_inkern_init); + +static void iio_inkern_exit(void) +{ + platform_driver_unregister(&iio_hwmon_driver); +} +module_exit(iio_inkern_exit); + +MODULE_AUTHOR("Jonathan Cameron <jic23@xxxxxxxxx>"); +MODULE_DESCRIPTION("IIO to hwmon driver"); +MODULE_LICENSE("GPL v2"); -- 1.7.7 _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors