Merge branch 'vexpress-drivers' of git://git.linaro.org/people/pawelmoll/linux into next/drivers

Versatile Express changes from Pawel Moll <pawel.moll@arm.com>:

* 'vexpress-drivers' of git://git.linaro.org/people/pawelmoll/linux:
  ARM: vexpress: Reset driver
  hwmon: Versatile Express hwmon driver

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

6 files changed, 436 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/hwmon/vexpress.txt b/Documentation/devicetree/bindings/hwmon/vexpress.txt
new file mode 100644
index 000000000000..9c27ed694bbb
--- /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@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 000000000000..557d6d5ad90d
--- /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/arch/arm/mach-vexpress/reset.c b/arch/arm/mach-vexpress/reset.c
new file mode 100644
index 000000000000..465923aa3819
--- /dev/null
+++ b/arch/arm/mach-vexpress/reset.c
@@ -0,0 +1,141 @@
+/*
+ * 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
+ */
+
+#include <linux/jiffies.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/stat.h>
+#include <linux/vexpress.h>
+
+static void vexpress_reset_do(struct device *dev, const char *what)
+{
+        int err = -ENOENT;
+        struct vexpress_config_func *func =
+                        vexpress_config_func_get_by_dev(dev);
+
+        if (func) {
+                unsigned long timeout;
+
+                err = vexpress_config_write(func, 0, 0);
+
+                timeout = jiffies + HZ;
+                while (time_before(jiffies, timeout))
+                        cpu_relax();
+        }
+
+        dev_emerg(dev, "Unable to %s (%d)\n", what, err);
+}
+
+static struct device *vexpress_power_off_device;
+
+void vexpress_power_off(void)
+{
+        vexpress_reset_do(vexpress_power_off_device, "power off");
+}
+
+static struct device *vexpress_restart_device;
+
+void vexpress_restart(char str, const char *cmd)
+{
+        vexpress_reset_do(vexpress_restart_device, "restart");
+}
+
+static ssize_t vexpress_reset_active_show(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        return sprintf(buf, "%d\n", vexpress_restart_device == dev);
+}
+
+static ssize_t vexpress_reset_active_store(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        long value;
+        int err = kstrtol(buf, 0, &value);
+
+        if (!err && value)
+                vexpress_restart_device = dev;
+
+        return err ? err : count;
+}
+
+DEVICE_ATTR(active, S_IRUGO | S_IWUSR, vexpress_reset_active_show,
+                vexpress_reset_active_store);
+
+
+enum vexpress_reset_func { FUNC_RESET, FUNC_SHUTDOWN, FUNC_REBOOT };
+
+static struct of_device_id vexpress_reset_of_match[] = {
+        {
+                .compatible = "arm,vexpress-reset",
+                .data = (void *)FUNC_RESET,
+        }, {
+                .compatible = "arm,vexpress-shutdown",
+                .data = (void *)FUNC_SHUTDOWN
+        }, {
+                .compatible = "arm,vexpress-reboot",
+                .data = (void *)FUNC_REBOOT
+        },
+        {}
+};
+
+static int vexpress_reset_probe(struct platform_device *pdev)
+{
+        enum vexpress_reset_func func;
+        const struct of_device_id *match =
+                        of_match_device(vexpress_reset_of_match, &pdev->dev);
+
+        if (match)
+                func = (enum vexpress_reset_func)match->data;
+        else
+                func = pdev->id_entry->driver_data;
+
+        switch (func) {
+        case FUNC_SHUTDOWN:
+                vexpress_power_off_device = &pdev->dev;
+                break;
+        case FUNC_RESET:
+                if (!vexpress_restart_device)
+                        vexpress_restart_device = &pdev->dev;
+                device_create_file(&pdev->dev, &dev_attr_active);
+                break;
+        case FUNC_REBOOT:
+                vexpress_restart_device = &pdev->dev;
+                device_create_file(&pdev->dev, &dev_attr_active);
+                break;
+        };
+
+        return 0;
+}
+
+static const struct platform_device_id vexpress_reset_id_table[] = {
+        { .name = "vexpress-reset", .driver_data = FUNC_RESET, },
+        { .name = "vexpress-shutdown", .driver_data = FUNC_SHUTDOWN, },
+        { .name = "vexpress-reboot", .driver_data = FUNC_REBOOT, },
+        {}
+};
+
+static struct platform_driver vexpress_reset_driver = {
+        .probe = vexpress_reset_probe,
+        .driver = {
+                .name = "vexpress-reset",
+                .of_match_table = vexpress_reset_of_match,
+        },
+        .id_table = vexpress_reset_id_table,
+};
+
+static int __init vexpress_reset_init(void)
+{
+        return platform_driver_register(&vexpress_reset_driver);
+}
+device_initcall(vexpress_reset_init);
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index c4633de64465..db213fe958a5 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1197,6 +1197,14 @@ 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 8d5fcb5e8e9f..aac8b7c619d6 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -121,6 +121,7 @@ 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 000000000000..59fd1268e58a
--- /dev/null
+++ b/drivers/hwmon/vexpress.c
@@ -0,0 +1,229 @@
+/*
+ * 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/hwmon-sysfs.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;
+};
+
+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);
+
+        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);
+
+        if (!label)
+                return -ENOENT;
+
+        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_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 /
+                        to_sensor_dev_attr(dev_attr)->index);
+}
+
+static ssize_t vexpress_hwmon_u64_show(struct device *dev,
+                struct device_attribute *dev_attr, char *buffer)
+{
+        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,
+                        to_sensor_dev_attr(dev_attr)->index));
+}
+
+static DEVICE_ATTR(name, S_IRUGO, vexpress_hwmon_name_show, NULL);
+
+#define VEXPRESS_HWMON_ATTRS(_name, _label_attr, _input_attr)   \
+struct attribute *vexpress_hwmon_attrs_##_name[] = {            \
+        &dev_attr_name.attr,                                    \
+        &dev_attr_##_label_attr.attr,                           \
+        &sensor_dev_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 SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, vexpress_hwmon_u32_show,
+                NULL, 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 SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, vexpress_hwmon_u32_show,
+                NULL, 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 SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, vexpress_hwmon_u32_show,
+                NULL, 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 SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, vexpress_hwmon_u32_show,
+                NULL, 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 SENSOR_DEVICE_ATTR(energy1_input, S_IRUGO, vexpress_hwmon_u64_show,
+                NULL, 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
+        {
+                .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);
+
+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)
+                return -ENOMEM;
+        platform_set_drvdata(pdev, data);
+
+        match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
+        if (!match)
+                return -ENODEV;
+
+        data->func = vexpress_config_func_get_by_dev(&pdev->dev);
+        if (!data->func)
+                return -ENODEV;
+
+        err = sysfs_create_group(&pdev->dev.kobj, match->data);
+        if (err)
+                goto error;
+
+        data->hwmon_dev = hwmon_device_register(&pdev->dev);
+        if (IS_ERR(data->hwmon_dev)) {
+                err = PTR_ERR(data->hwmon_dev);
+                goto error;
+        }
+
+        return 0;
+
+error:
+        sysfs_remove_group(&pdev->dev.kobj, match->data);
+        vexpress_config_func_put(data->func);
+        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,
+        },
+};
+
+module_platform_driver(vexpress_hwmon_driver);
+
+MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
+MODULE_DESCRIPTION("Versatile Express hwmon sensors driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:vexpress-hwmon");