[PATCH v3] hwmon: Versatile Express hwmon driver
Guenter Roeck
linux at roeck-us.net
Thu Sep 20 19:57:27 EDT 2012
On Thu, Sep 20, 2012 at 05:54:18PM +0100, Pawel Moll wrote:
> hwmon framework driver for Versatile Express sensors, providing
> information about board level voltage (only when regulator driver
> is not configured), currents, temperature and power/energy usage.
> Labels for the values can be defined as DT properties.
>
> Signed-off-by: Pawel Moll <pawel.moll at arm.com>
> ---
> .../devicetree/bindings/hwmon/vexpress.txt | 23 ++
> Documentation/hwmon/vexpress | 34 +++
> drivers/hwmon/Kconfig | 8 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/vexpress.c | 255 ++++++++++++++++++++
> 5 files changed, 321 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/hwmon/vexpress.txt
> create mode 100644 Documentation/hwmon/vexpress
> create mode 100644 drivers/hwmon/vexpress.c
>
Your patch is substantially corrupted and unusable as patch file. Did you send
it through outlook ?
> diff --git a/Documentation/devicetree/bindings/hwmon/vexpress.txt b/Documentation/devicetree/bindings/hwmon/vexpress.txt
> new file mode 100644
> index 0000000..9c27ed6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/vexpress.txt
> @@ -0,0 +1,23 @@
> +Versatile Express hwmon sensors
> +-------------------------------
> +
> +Requires node properties:
> +- "compatible" value : one of
> + "arm,vexpress-volt"
> + "arm,vexpress-amp"
> + "arm,vexpress-temp"
> + "arm,vexpress-power"
> + "arm,vexpress-energy"
> +- "arm,vexpress-sysreg,func" when controlled via vexpress-sysreg
> + (see Documentation/devicetree/bindings/arm/vexpress-sysreg.txt
> + for more details)
> +
> +Optional node properties:
> +- label : string describing the monitored value
> +
> +Example:
> + energy at 0 {
> + compatible = "arm,vexpress-energy";
> + arm,vexpress-sysreg,func = <13 0>;
> + label = "A15 Jcore";
> + };
> diff --git a/Documentation/hwmon/vexpress b/Documentation/hwmon/vexpress
> new file mode 100644
> index 0000000..557d6d5
> --- /dev/null
> +++ b/Documentation/hwmon/vexpress
> @@ -0,0 +1,34 @@
> +Kernel driver vexpress
> +======================
> +
> +Supported systems:
> + * ARM Ltd. Versatile Express platform
> + Prefix: 'vexpress'
> + Datasheets:
> + * "Hardware Description" sections of the Technical Reference Manuals
> + for the Versatile Express boards:
> + http://infocenter.arm.com/help/topic/com.arm.doc.subset.boards.express/index.html
> + * Section "4.4.14. System Configuration registers" of the V2M-P1 TRM:
> + http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0447-/index.html
> +
> +Author: Pawel Moll
> +
> +Description
> +-----------
> +
> +Versatile Express platform (http://www.arm.com/versatileexpress/) is a
> +reference & prototyping system for ARM Ltd. processors. It can be set up
> +from a wide range of boards, each of them containing (apart of the main
> +chip/FPGA) a number of microcontrollers responsible for platform
> +configuration and control. Theses microcontrollers can also monitor the
> +board and its environment by a number of internal and external sensors,
> +providing information about power lines voltages and currents, board
> +temperature and power usage. Some of them also calculate consumed energy
> +and provide a cumulative use counter.
> +
> +The configuration devices are _not_ memory mapped and must be accessed
> +via a custom interface, abstracted by the "vexpress_config" API.
> +
> +As these devices are non-discoverable, they must be described in a Device
> +Tree passed to the kernel. Details of the DT binding for them can be found
> +in Documentation/devicetree/bindings/hwmon/vexpress.txt.
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index b0a2e4c..7359a07 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1187,6 +1187,14 @@ config SENSORS_TWL4030_MADC
> This driver can also be built as a module. If so it will be called
> twl4030-madc-hwmon.
>
> +config SENSORS_VEXPRESS
> + tristate "Versatile Express"
> + depends on VEXPRESS_CONFIG
> + help
> + This driver provides support for hardware sensors available on
> + the ARM Ltd's Versatile Express platform. It can provide wide
> + range of information like temperature, power, energy.
> +
> config SENSORS_VIA_CPUTEMP
> tristate "VIA CPU temperature sensor"
> depends on X86
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 7aa9811..e719a7d 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -120,6 +120,7 @@ obj-$(CONFIG_SENSORS_TMP102) += tmp102.o
> obj-$(CONFIG_SENSORS_TMP401) += tmp401.o
> obj-$(CONFIG_SENSORS_TMP421) += tmp421.o
> obj-$(CONFIG_SENSORS_TWL4030_MADC)+= twl4030-madc-hwmon.o
> +obj-$(CONFIG_SENSORS_VEXPRESS) += vexpress.o
> obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
> obj-$(CONFIG_SENSORS_VIA686A) += via686a.o
> obj-$(CONFIG_SENSORS_VT1211) += vt1211.o
> diff --git a/drivers/hwmon/vexpress.c b/drivers/hwmon/vexpress.c
> new file mode 100644
> index 0000000..d9f091e
> --- /dev/null
> +++ b/drivers/hwmon/vexpress.c
> @@ -0,0 +1,255 @@
> +/*
> + * 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.
> + *
> + * 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.
> + *
> + * Copyright (C) 2012 ARM Limited
> + */
> +
> +#define DRVNAME "vexpress-hwmon"
> +#define pr_fmt(fmt) DRVNAME ": " fmt
> +
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/hwmon.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/vexpress.h>
> +
> +struct vexpress_hwmon_data {
> + struct device *hwmon_dev;
> + struct vexpress_config_func *func;
> +};
> +
> +struct vexpress_hwmon_attr {
> + struct device_attribute dev_attr;
> + u32 divisor;
> +};
> +
Unnecessary - see below.
> +static ssize_t vexpress_hwmon_name_show(struct device *dev,
> + struct device_attribute *dev_attr, char *buffer)
> +{
> + const char *compatible = of_get_property(dev->of_node, "compatible",
> + NULL);
> +
Can compatible be NULL ?
> + return sprintf(buffer, "%s\n", compatible);
> +}
> +
> +static ssize_t vexpress_hwmon_label_show(struct device *dev,
> + struct device_attribute *dev_attr, char *buffer)
> +{
> + const char *label = of_get_property(dev->of_node, "label", NULL);
> +
Can label be NULL (eg if missing in device tree data) ?
What happens if it is NULL ? Seems to me the label attribute should not exist in
that case.
> + return snprintf(buffer, PAGE_SIZE, "%s\n", label);
> +}
> +
> +static ssize_t vexpress_hwmon_u32_show(struct device *dev,
> + struct device_attribute *dev_attr, char *buffer)
> +{
> + struct vexpress_hwmon_attr *attr = container_of(dev_attr,
> + struct vexpress_hwmon_attr, dev_attr);
> + struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
> + int err;
> + u32 value;
> +
> + err = vexpress_config_read(data->func, 0, &value);
> + if (err)
> + return err;
> +
> + return snprintf(buffer, PAGE_SIZE, "%u\n", value / attr->divisor);
> +}
> +
> +static ssize_t vexpress_hwmon_u64_show(struct device *dev,
> + struct device_attribute *dev_attr, char *buffer)
> +{
> + struct vexpress_hwmon_attr *attr = container_of(dev_attr,
> + struct vexpress_hwmon_attr, dev_attr);
> + struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
> + int err;
> + u32 value_hi, value_lo;
> +
> + err = vexpress_config_read(data->func, 0, &value_lo);
> + if (err)
> + return err;
> +
> + err = vexpress_config_read(data->func, 1, &value_hi);
> + if (err)
> + return err;
> +
> + return snprintf(buffer, PAGE_SIZE, "%llu\n",
> + div_u64(((u64)value_hi << 32) | value_lo,
> + attr->divisor));
> +}
> +
> +static DEVICE_ATTR(name, S_IRUGO, vexpress_hwmon_name_show, NULL);
> +
> +#define VEXPRESS_HWMON_ATTR(_name, _show, _divisor) \
> +struct vexpress_hwmon_attr vexpress_hwmon_attr_##_name = { \
> + .dev_attr = __ATTR(_name, S_IRUGO, _show, NULL), \
> + .divisor = _divisor, \
> +}
You should be able to use SENSOR_DEVICE_ATTR here.
> +
> +#define VEXPRESS_HWMON_ATTRS(_name, _label_attr, _input_attr) \
> +struct attribute *vexpress_hwmon_attrs_##_name[] = { \
> + &dev_attr_name.attr, \
> + &dev_attr_##_label_attr.attr, \
> + &vexpress_hwmon_attr_##_input_attr.dev_attr.attr, \
> + NULL \
> +}
> +
> +#if !defined(CONFIG_REGULATOR_VEXPRESS)
> +static DEVICE_ATTR(in1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
> +static VEXPRESS_HWMON_ATTR(in1_input, vexpress_hwmon_u32_show, 1000);
> +static VEXPRESS_HWMON_ATTRS(volt, in1_label, in1_input);
> +static struct attribute_group vexpress_hwmon_group_volt = {
> + .attrs = vexpress_hwmon_attrs_volt,
> +};
> +#endif
> +
> +static DEVICE_ATTR(curr1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
> +static VEXPRESS_HWMON_ATTR(curr1_input, vexpress_hwmon_u32_show, 1000);
> +static VEXPRESS_HWMON_ATTRS(amp, curr1_label, curr1_input);
> +static struct attribute_group vexpress_hwmon_group_amp = {
> + .attrs = vexpress_hwmon_attrs_amp,
> +};
> +
> +static DEVICE_ATTR(temp1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
> +static VEXPRESS_HWMON_ATTR(temp1_input, vexpress_hwmon_u32_show, 1000);
> +static VEXPRESS_HWMON_ATTRS(temp, temp1_label, temp1_input);
> +static struct attribute_group vexpress_hwmon_group_temp = {
> + .attrs = vexpress_hwmon_attrs_temp,
> +};
> +
> +static DEVICE_ATTR(power1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
> +static VEXPRESS_HWMON_ATTR(power1_input, vexpress_hwmon_u32_show, 1);
> +static VEXPRESS_HWMON_ATTRS(power, power1_label, power1_input);
> +static struct attribute_group vexpress_hwmon_group_power = {
> + .attrs = vexpress_hwmon_attrs_power,
> +};
> +
> +static DEVICE_ATTR(energy1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
> +static VEXPRESS_HWMON_ATTR(energy1_input, vexpress_hwmon_u64_show, 1);
> +static VEXPRESS_HWMON_ATTRS(energy, energy1_label, energy1_input);
> +static struct attribute_group vexpress_hwmon_group_energy = {
> + .attrs = vexpress_hwmon_attrs_energy,
> +};
> +
> +static struct of_device_id vexpress_hwmon_of_match[] = {
> +#if !defined(CONFIG_REGULATOR_VEXPRESS)
> + {
> + .compatible = "arm,vexpress-volt",
> + .data = &vexpress_hwmon_group_volt,
> + },
> +#endif
Just wondering - is the hwmon driver mutually exclusive with the regulator
driver, or can both coexist ?
FWIW, the references to "arm,vexpress-volt" I can find on the web all do not
include "label", so I think you'll really have to look into what happens if
there is no such property.
> + {
> + .compatible = "arm,vexpress-amp",
> + .data = &vexpress_hwmon_group_amp,
> + }, {
> + .compatible = "arm,vexpress-temp",
> + .data = &vexpress_hwmon_group_temp,
> + }, {
> + .compatible = "arm,vexpress-power",
> + .data = &vexpress_hwmon_group_power,
> + }, {
> + .compatible = "arm,vexpress-energy",
> + .data = &vexpress_hwmon_group_energy,
> + },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, vexpress_hwmon_of_match);
> +
Just wondering .... would the following work ?
hwmon at 0 {
compatible = "arm,vexpress-hwmon";
volt at 0 {
/* Logic level voltage */
arm,vexpress-sysreg,func = <2 0>;
label = "VIO";
};
amp at 0 {
/* Total current for the two cores */
arm,vexpress-sysreg,func = <3 0>;
label = "Core current";
};
temp at 0 {
/* DCC internal temperature */
arm,vexpress-sysreg,func = <4 0>;
label = "DCC";
};
power at 0 {
/* Total power */
arm,vexpress-sysreg,func = <12 0>;
label = "Core power";
};
energy at 0 {
/* Total energy */
arm,vexpress-sysreg,func = <13 0>;
label = "Core energy";
};
};
I am not a device tree expert, but it seems to me that you would only have a single device node
with this approach, and you could parse its children with for_each_child_of_node().
> +static int vexpress_hwmon_probe(struct platform_device *pdev)
> +{
> + int err;
> + const struct of_device_id *match;
> + struct vexpress_hwmon_data *data;
> +
> + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
> + if (!data) {
> + err = -ENOMEM;
> + goto error_kzalloc;
> + }
> +
> + match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
> + if (!match) {
> + err = -EINVAL;
ENODEV ?
> + goto error_match_device;
> + }
> +
> + data->func = vexpress_config_func_get_by_dev(&pdev->dev);
> + if (!data->func) {
> + err = -ENXIO;
ENODEV ?
> + goto error_get_func;
> + }
> +
> + err = sysfs_create_group(&pdev->dev.kobj, match->data);
> + if (err)
> + goto error_create_group;
> +
> + data->hwmon_dev = hwmon_device_register(&pdev->dev);
> + if (IS_ERR(data->hwmon_dev)) {
> + err = PTR_ERR(data->hwmon_dev);
> + goto error_hwmon_device_register;
> + }
> +
> + platform_set_drvdata(pdev, data);
> +
Must be set before sysfs files are created.
> + return 0;
> +
> +error_hwmon_device_register:
> + sysfs_remove_group(&pdev->dev.kobj, match->data);
> +error_create_group:
> + vexpress_config_func_put(data->func);
> +error_get_func:
> +error_match_device:
> +error_kzalloc:
Just return the error instead of using goto. No need for all those goto labels.
> + return err;
> +}
> +
> +static int __devexit vexpress_hwmon_remove(struct platform_device *pdev)
> +{
> + struct vexpress_hwmon_data *data = platform_get_drvdata(pdev);
> + const struct of_device_id *match;
> +
> + hwmon_device_unregister(data->hwmon_dev);
> +
> + match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
> + sysfs_remove_group(&pdev->dev.kobj, match->data);
> +
> + vexpress_config_func_put(data->func);
> +
> + return 0;
> +}
> +
> +static struct platform_driver vexpress_hwmon_driver = {
> + .probe = vexpress_hwmon_probe,
> + .remove = __devexit_p(vexpress_hwmon_remove),
> + .driver = {
> + .name = DRVNAME,
> + .owner = THIS_MODULE,
> + .of_match_table = vexpress_hwmon_of_match,
> + },
> +};
> +
> +static int __init vexpress_hwmon_init(void)
> +{
> + return platform_driver_register(&vexpress_hwmon_driver);
> +}
> +
> +static void __exit vexpress_hwmon_exit(void)
> +{
> + platform_driver_unregister(&vexpress_hwmon_driver);
> +}
> +
> +MODULE_AUTHOR("Pawel Moll <pawel.moll at arm.com>");
> +MODULE_DESCRIPTION("Versatile Express hwmon sensors driver");
> +MODULE_LICENSE("GPL");
> +
> +module_init(vexpress_hwmon_init);
> +module_exit(vexpress_hwmon_exit);
You can use module_platform_driver here.
> --
> 1.7.9.5
>
>
>
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