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Added hwmon/thermal driver for reporting core temperature. Thanks Dorian

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1 parent c8edb23 commit e33263e7eab2d05349b438f6a4a8d1924686a824 @popcornmix popcornmix committed Sep 13, 2012
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11 arch/arm/mach-bcm2708/bcm2708.c
@@ -592,6 +592,14 @@ static struct platform_device bcm2708_bsc1_device = {
.resource = bcm2708_bsc1_resources,
};
+static struct platform_device bcm2835_hwmon_device = {
+ .name = "bcm2835_hwmon",
+};
+
+static struct platform_device bcm2835_thermal_device = {
+ .name = "bcm2835_thermal",
+};
+
int __init bcm_register_device(struct platform_device *pdev)
{
int ret;
@@ -656,6 +664,9 @@ void __init bcm2708_init(void)
bcm_register_device(&bcm2708_bsc0_device);
bcm_register_device(&bcm2708_bsc1_device);
+ bcm_register_device(&bcm2835_hwmon_device);
+ bcm_register_device(&bcm2835_thermal_device);
+
#ifdef CONFIG_BCM2708_VCMEM
{
extern void vc_mem_connected_init(void);
View
9 drivers/hwmon/Kconfig
@@ -1361,6 +1361,15 @@ config SENSORS_MC13783_ADC
help
Support for the A/D converter on MC13783 PMIC.
+config SENSORS_BCM2835
+ tristate "Broadcom BCM2835 HWMON Driver"
+ help
+ If you say yes here you get support for the hardware
+ monitoring features of the BCM2835 Chip
+
+ This driver can also be built as a module. If so, the module
+ will be called bcm2835-hwmon.
+
if ACPI
comment "ACPI drivers"
View
1 drivers/hwmon/Makefile
@@ -125,6 +125,7 @@ obj-$(CONFIG_SENSORS_W83L785TS) += w83l785ts.o
obj-$(CONFIG_SENSORS_W83L786NG) += w83l786ng.o
obj-$(CONFIG_SENSORS_WM831X) += wm831x-hwmon.o
obj-$(CONFIG_SENSORS_WM8350) += wm8350-hwmon.o
+obj-$(CONFIG_SENSORS_BCM2835) += bcm2835-hwmon.o
obj-$(CONFIG_PMBUS) += pmbus/
View
211 drivers/hwmon/bcm2835-hwmon.c
@@ -0,0 +1,211 @@
+//bcm2835-hwmon.c
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+#include <mach/vcio.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+
+#define MODULE_NAME "bcm2835_hwmon"
+
+/*#define HWMON_DEBUG_ENABLE*/
+
+#ifdef HWMON_DEBUG_ENABLE
+#define print_debug(fmt,...) printk(KERN_INFO "%s:%s:%d: "fmt"\n", MODULE_NAME, __func__, __LINE__, ##__VA_ARGS__)
+#else
+#define print_debug(fmt,...)
+#endif
+#define print_err(fmt,...) printk(KERN_ERR "%s:%s:%d: "fmt"\n", MODULE_NAME, __func__,__LINE__, ##__VA_ARGS__)
+#define print_info(fmt,...) printk(KERN_INFO "%s: "fmt"\n", MODULE_NAME, ##__VA_ARGS__)
+
+#define VC_TAG_GET_TEMP 0x00030006
+#define VC_TAG_GET_MAX_TEMP 0x0003000A
+struct bcm2835_hwmon_data {
+ struct device *hwmon_dev;
+};
+
+/* --- STRUCTS --- */
+
+/* tag part of the message */
+struct vc_msg_tag {
+ uint32_t tag_id; /* the tag ID for the temperature */
+ uint32_t buffer_size; /* size of the buffer (should be 8) */
+ uint32_t request_code; /* identifies message as a request (should be 0) */
+ uint32_t id; /* extra ID field (should be 0) */
+ uint32_t val; /* returned value of the temperature */
+};
+
+/* message structure to be sent to videocore */
+struct vc_msg {
+ uint32_t msg_size; /* simply, sizeof(struct vc_msg) */
+ uint32_t request_code; /* holds various information like the success and number of bytes returned (refer to mailboxes wiki) */
+ struct vc_msg_tag tag; /* the tag structure above to make */
+ uint32_t end_tag; /* an end identifier, should be set to NULL */
+};
+
+typedef enum {
+ TEMP,
+ MAX_TEMP,
+} temp_type;
+
+/* --- PROTOTYPES --- */
+static ssize_t bcm2835_get_temp(struct device *dev, struct device_attribute *attr, char *buf);
+static ssize_t bcm2835_get_name(struct device *dev, struct device_attribute *attr, char *buf);
+
+/* --- GLOBALS --- */
+
+static struct bcm2835_hwmon_data *bcm2835_data;
+static struct platform_driver bcm2835_hwmon_driver;
+
+static SENSOR_DEVICE_ATTR(name, S_IRUGO,bcm2835_get_name,NULL,0);
+static SENSOR_DEVICE_ATTR(temp1_input,S_IRUGO,bcm2835_get_temp,NULL,TEMP);
+static SENSOR_DEVICE_ATTR(temp,S_IRUGO,bcm2835_get_temp,NULL,TEMP);
+static SENSOR_DEVICE_ATTR(temp1_max,S_IRUGO,bcm2835_get_temp,NULL,MAX_TEMP);
+static SENSOR_DEVICE_ATTR(trip_point_0_temp,S_IRUGO,bcm2835_get_temp,NULL,MAX_TEMP);
+
+static struct attribute* bcm2835_attributes[] = {
+ &sensor_dev_attr_name.dev_attr.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp.dev_attr.attr,
+ &sensor_dev_attr_trip_point_0_temp.dev_attr.attr,
+ NULL,
+};
+
+static struct attribute_group bcm2835_attr_group = {
+ .attrs = bcm2835_attributes,
+};
+
+/* --- FUNCTIONS --- */
+
+static ssize_t bcm2835_get_name(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf,"bcm2835_hwmon\n");
+}
+
+static ssize_t bcm2835_get_temp(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct vc_msg msg;
+ int result;
+ uint temp = 0;
+ int index = ((struct sensor_device_attribute*)to_sensor_dev_attr(attr))->index;
+
+ print_debug("IN");
+
+ /* wipe all previous message data */
+ memset(&msg, 0, sizeof msg);
+
+ /* determine the message type */
+ if(index == TEMP)
+ msg.tag.tag_id = VC_TAG_GET_TEMP;
+ else if (index == MAX_TEMP)
+ msg.tag.tag_id = VC_TAG_GET_MAX_TEMP;
+ else
+ {
+ print_debug("Unknown temperature message!");
+ return -EINVAL;
+ }
+
+ msg.msg_size = sizeof msg;
+ msg.tag.buffer_size = 8;
+
+ /* send the message */
+ result = bcm_mailbox_property(&msg, sizeof msg);
+
+ /* check if it was all ok and return the rate in milli degrees C */
+ if (result == 0 && (msg.request_code & 0x80000000))
+ temp = (uint)msg.tag.val;
+ #ifdef HWMON_DEBUG_ENABLE
+ else
+ print_debug("Failed to get temperature!");
+ #endif
+ print_debug("Got temperature as %u",temp);
+ print_debug("OUT");
+ return sprintf(buf, "%u\n", temp);
+}
+
+
+static int bcm2835_hwmon_probe(struct platform_device *pdev)
+{
+ int err;
+
+ print_debug("IN");
+ print_debug("HWMON Driver has been probed!");
+
+ /* check that the device isn't null!*/
+ if(pdev == NULL)
+ {
+ print_debug("Platform device is empty!");
+ return -ENODEV;
+ }
+
+ /* allocate memory for neccessary data */
+ bcm2835_data = kzalloc(sizeof(struct bcm2835_hwmon_data),GFP_KERNEL);
+ if(!bcm2835_data)
+ {
+ print_debug("Unable to allocate memory for hwmon data!");
+ err = -ENOMEM;
+ goto kzalloc_error;
+ }
+
+ /* create the sysfs files */
+ if(sysfs_create_group(&pdev->dev.kobj, &bcm2835_attr_group))
+ {
+ print_debug("Unable to create sysfs files!");
+ err = -EFAULT;
+ goto sysfs_error;
+ }
+
+ /* register the hwmon device */
+ bcm2835_data->hwmon_dev = hwmon_device_register(&pdev->dev);
+ if (IS_ERR(bcm2835_data->hwmon_dev))
+ {
+ err = PTR_ERR(bcm2835_data->hwmon_dev);
+ goto hwmon_error;
+ }
+ print_debug("OUT");
+ return 0;
+
+ /* error goto's */
+ hwmon_error:
+ sysfs_remove_group(&pdev->dev.kobj, &bcm2835_attr_group);
+
+ sysfs_error:
+ kfree(bcm2835_data);
+
+ kzalloc_error:
+
+ return err;
+
+}
+
+static int bcm2835_hwmon_remove(struct platform_device *pdev)
+{
+ print_debug("IN");
+ hwmon_device_unregister(bcm2835_data->hwmon_dev);
+
+ sysfs_remove_group(&pdev->dev.kobj, &bcm2835_attr_group);
+ print_debug("OUT");
+ return 0;
+}
+
+/* Hwmon Driver */
+static struct platform_driver bcm2835_hwmon_driver = {
+ .probe = bcm2835_hwmon_probe,
+ .remove = bcm2835_hwmon_remove,
+ .driver = {
+ .name = "bcm2835_hwmon",
+ .owner = THIS_MODULE,
+ },
+};
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dorian Peake");
+MODULE_DESCRIPTION("HW Monitor driver for bcm2835 chip");
+
+module_platform_driver(bcm2835_hwmon_driver);
View
10 drivers/thermal/Kconfig
@@ -18,3 +18,13 @@ config THERMAL_HWMON
depends on THERMAL
depends on HWMON=y || HWMON=THERMAL
default y
+
+if THERMAL
+
+config THERMAL_BCM2835
+ tristate "BCM2835 Thermal Driver"
+ help
+ This will enable temperature monitoring for the Broadcom BCM2835
+ chip. If built as a module, it will be called 'bcm2835-thermal'.
+
+endif # THERMAL_BCM2835
View
1 drivers/thermal/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_THERMAL) += thermal_sys.o
+obj-$(CONFIG_THERMAL_BCM2835) += bcm2835-thermal.o
View
195 drivers/thermal/bcm2835-thermal.c
@@ -0,0 +1,195 @@
+//bcm2835-thermal.c
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <mach/vcio.h>
+#include <linux/thermal.h>
+
+
+/* --- DEFINITIONS --- */
+#define MODULE_NAME "bcm2835_thermal"
+
+/*#define THERMAL_DEBUG_ENABLE*/
+
+#ifdef THERMAL_DEBUG_ENABLE
+#define print_debug(fmt,...) printk(KERN_INFO "%s:%s:%d: "fmt"\n", MODULE_NAME, __func__, __LINE__, ##__VA_ARGS__)
+#else
+#define print_debug(fmt,...)
+#endif
+#define print_err(fmt,...) printk(KERN_ERR "%s:%s:%d: "fmt"\n", MODULE_NAME, __func__,__LINE__, ##__VA_ARGS__)
+#define print_info(fmt,...) printk(KERN_INFO "%s: "fmt"\n", MODULE_NAME, ##__VA_ARGS__)
+
+#define VC_TAG_GET_TEMP 0x00030006
+#define VC_TAG_GET_MAX_TEMP 0x0003000A
+
+typedef enum {
+ TEMP,
+ MAX_TEMP,
+} temp_type;
+
+/* --- STRUCTS --- */
+/* tag part of the message */
+struct vc_msg_tag {
+ uint32_t tag_id; /* the tag ID for the temperature */
+ uint32_t buffer_size; /* size of the buffer (should be 8) */
+ uint32_t request_code; /* identifies message as a request (should be 0) */
+ uint32_t id; /* extra ID field (should be 0) */
+ uint32_t val; /* returned value of the temperature */
+};
+
+/* message structure to be sent to videocore */
+struct vc_msg {
+ uint32_t msg_size; /* simply, sizeof(struct vc_msg) */
+ uint32_t request_code; /* holds various information like the success and number of bytes returned (refer to mailboxes wiki) */
+ struct vc_msg_tag tag; /* the tag structure above to make */
+ uint32_t end_tag; /* an end identifier, should be set to NULL */
+};
+
+struct bcm2835_thermal_data {
+ struct thermal_zone_device *thermal_dev;
+ struct vc_msg msg;
+};
+
+/* --- PROTOTYPES --- */
+static int bcm2835_get_temp(struct thermal_zone_device *thermal_dev, unsigned long *);
+static int bcm2835_get_max_temp(struct thermal_zone_device *thermal_dev, int, unsigned long *);
+static int bcm2835_get_trip_type(struct thermal_zone_device *thermal_dev, int trip_num, enum thermal_trip_type *trip_type);
+static int bcm2835_get_mode(struct thermal_zone_device *thermal_dev, enum thermal_device_mode *dev_mode);
+
+/* --- GLOBALS --- */
+static struct bcm2835_thermal_data bcm2835_data;
+
+/* Thermal Device Operations */
+static struct thermal_zone_device_ops ops;
+
+/* --- FUNCTIONS --- */
+static int bcm2835_get_max_temp(struct thermal_zone_device *thermal_dev, int trip_num, unsigned long *temp)
+{
+ int result;
+
+ print_debug("IN");
+
+ /* wipe all previous message data */
+ memset(&bcm2835_data.msg, 0, sizeof bcm2835_data.msg);
+
+ /* prepare message */
+ bcm2835_data.msg.msg_size = sizeof bcm2835_data.msg;
+ bcm2835_data.msg.tag.buffer_size = 8;
+ bcm2835_data.msg.tag.tag_id = VC_TAG_GET_MAX_TEMP;
+
+ /* send the message */
+ result = bcm_mailbox_property(&bcm2835_data.msg, sizeof bcm2835_data.msg);
+
+ /* check if it was all ok and return the rate in milli degrees C */
+ if (result == 0 && (bcm2835_data.msg.request_code & 0x80000000))
+ *temp = (uint)bcm2835_data.msg.tag.val;
+ #ifdef THERMAL_DEBUG_ENABLE
+ else
+ print_debug("Failed to get temperature!");
+ #endif
+ print_debug("Got temperature as %u",(uint)*temp);
+ print_debug("OUT");
+ return 0;
+}
+
+static int bcm2835_get_temp(struct thermal_zone_device *thermal_dev, unsigned long *temp)
+{
+ int result;
+
+ print_debug("IN");
+
+ /* wipe all previous message data */
+ memset(&bcm2835_data.msg, 0, sizeof bcm2835_data.msg);
+
+ /* prepare message */
+ bcm2835_data.msg.msg_size = sizeof bcm2835_data.msg;
+ bcm2835_data.msg.tag.buffer_size = 8;
+ bcm2835_data.msg.tag.tag_id = VC_TAG_GET_TEMP;
+
+ /* send the message */
+ result = bcm_mailbox_property(&bcm2835_data.msg, sizeof bcm2835_data.msg);
+
+ /* check if it was all ok and return the rate in milli degrees C */
+ if (result == 0 && (bcm2835_data.msg.request_code & 0x80000000))
+ *temp = (uint)bcm2835_data.msg.tag.val;
+ #ifdef THERMAL_DEBUG_ENABLE
@riemervdzee
riemervdzee Sep 14, 2012

If the tempeture read fails, maybe we should return an error code instead of returning 0 and keep *temp unchanged? The driver is a useful addition though, something I just needed :)

+ else
+ print_debug("Failed to get temperature!");
+ #endif
+ print_debug("Got temperature as %u",(uint)*temp);
+ print_debug("OUT");
+ return 0;
+}
+
+
+static int bcm2835_get_trip_type(struct thermal_zone_device * thermal_dev, int trip_num, enum thermal_trip_type *trip_type)
+{
+ *trip_type = THERMAL_TRIP_HOT;
+ return 0;
+}
+
+
+static int bcm2835_get_mode(struct thermal_zone_device *thermal_dev, enum thermal_device_mode *dev_mode)
+{
+ *dev_mode = THERMAL_DEVICE_ENABLED;
+ return 0;
+}
+
+
+static int bcm2835_thermal_probe(struct platform_device *pdev)
+{
+ print_debug("IN");
+ print_debug("THERMAL Driver has been probed!");
+
+ /* check that the device isn't null!*/
+ if(pdev == NULL)
+ {
+ print_debug("Platform device is empty!");
+ return -ENODEV;
+ }
+
+ if(!(bcm2835_data.thermal_dev = thermal_zone_device_register("bcm2835_thermal", 1, NULL, &ops,1,1,1000,1000)))
+ {
+ print_debug("Unable to register the thermal device!");
+ return -EFAULT;
+ }
+ return 0;
+}
+
+
+static int bcm2835_thermal_remove(struct platform_device *pdev)
+{
+ print_debug("IN");
+
+ thermal_zone_device_unregister(bcm2835_data.thermal_dev);
+
+ print_debug("OUT");
+
+ return 0;
+}
+
+static struct thermal_zone_device_ops ops = {
+ .get_temp = bcm2835_get_temp,
+ .get_trip_temp = bcm2835_get_max_temp,
+ .get_trip_type = bcm2835_get_trip_type,
+ .get_mode = bcm2835_get_mode,
+};
+
+/* Thermal Driver */
+static struct platform_driver bcm2835_thermal_driver = {
+ .probe = bcm2835_thermal_probe,
+ .remove = bcm2835_thermal_remove,
+ .driver = {
+ .name = "bcm2835_thermal",
+ .owner = THIS_MODULE,
+ },
+};
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dorian Peake");
+MODULE_DESCRIPTION("Thermal driver for bcm2835 chip");
+
+module_platform_driver(bcm2835_thermal_driver);

1 comment on commit e33263e

@cperrin88

I had been wondering if someone writes a kernel driver for the termal sensor and TADAAA!! here it is. Good work!

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