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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/hwmon/sl28cpld-hwmon.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hwmon/sl28cpld-hwmon.c')
-rw-r--r-- | drivers/hwmon/sl28cpld-hwmon.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/hwmon/sl28cpld-hwmon.c b/drivers/hwmon/sl28cpld-hwmon.c new file mode 100644 index 0000000000..e020f25c93 --- /dev/null +++ b/drivers/hwmon/sl28cpld-hwmon.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * sl28cpld hardware monitoring driver + * + * Copyright 2020 Kontron Europe GmbH + */ + +#include <linux/bitfield.h> +#include <linux/hwmon.h> +#include <linux/kernel.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/regmap.h> + +#define FAN_INPUT 0x00 +#define FAN_SCALE_X8 BIT(7) +#define FAN_VALUE_MASK GENMASK(6, 0) + +struct sl28cpld_hwmon { + struct regmap *regmap; + u32 offset; +}; + +static umode_t sl28cpld_hwmon_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + return 0444; +} + +static int sl28cpld_hwmon_read(struct device *dev, + enum hwmon_sensor_types type, u32 attr, + int channel, long *input) +{ + struct sl28cpld_hwmon *hwmon = dev_get_drvdata(dev); + unsigned int value; + int ret; + + switch (attr) { + case hwmon_fan_input: + ret = regmap_read(hwmon->regmap, hwmon->offset + FAN_INPUT, + &value); + if (ret) + return ret; + /* + * The register has a 7 bit value and 1 bit which indicates the + * scale. If the MSB is set, then the lower 7 bit has to be + * multiplied by 8, to get the correct reading. + */ + if (value & FAN_SCALE_X8) + value = FIELD_GET(FAN_VALUE_MASK, value) << 3; + + /* + * The counter period is 1000ms and the sysfs specification + * says we should assume 2 pulses per revolution. + */ + value *= 60 / 2; + + break; + default: + return -EOPNOTSUPP; + } + + *input = value; + return 0; +} + +static const struct hwmon_channel_info * const sl28cpld_hwmon_info[] = { + HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT), + NULL +}; + +static const struct hwmon_ops sl28cpld_hwmon_ops = { + .is_visible = sl28cpld_hwmon_is_visible, + .read = sl28cpld_hwmon_read, +}; + +static const struct hwmon_chip_info sl28cpld_hwmon_chip_info = { + .ops = &sl28cpld_hwmon_ops, + .info = sl28cpld_hwmon_info, +}; + +static int sl28cpld_hwmon_probe(struct platform_device *pdev) +{ + struct sl28cpld_hwmon *hwmon; + struct device *hwmon_dev; + int ret; + + if (!pdev->dev.parent) + return -ENODEV; + + hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL); + if (!hwmon) + return -ENOMEM; + + hwmon->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!hwmon->regmap) + return -ENODEV; + + ret = device_property_read_u32(&pdev->dev, "reg", &hwmon->offset); + if (ret) + return -EINVAL; + + hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, + "sl28cpld_hwmon", hwmon, + &sl28cpld_hwmon_chip_info, NULL); + if (IS_ERR(hwmon_dev)) + dev_err(&pdev->dev, "failed to register as hwmon device"); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct of_device_id sl28cpld_hwmon_of_match[] = { + { .compatible = "kontron,sl28cpld-fan" }, + {} +}; +MODULE_DEVICE_TABLE(of, sl28cpld_hwmon_of_match); + +static struct platform_driver sl28cpld_hwmon_driver = { + .probe = sl28cpld_hwmon_probe, + .driver = { + .name = "sl28cpld-fan", + .of_match_table = sl28cpld_hwmon_of_match, + }, +}; +module_platform_driver(sl28cpld_hwmon_driver); + +MODULE_DESCRIPTION("sl28cpld Hardware Monitoring Driver"); +MODULE_AUTHOR("Michael Walle <michael@walle.cc>"); +MODULE_LICENSE("GPL"); |