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|
--- /dev/null
+++ b/drivers/thermal/bcm2835-thermal.c
@@ -0,0 +1,184 @@
+/*****************************************************************************
+* Copyright 2011 Broadcom Corporation. All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+#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 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;
+};
+
+/* --- GLOBALS --- */
+static struct bcm2835_thermal_data bcm2835_data;
+
+/* Thermal Device Operations */
+static struct thermal_zone_device_ops ops;
+
+/* --- FUNCTIONS --- */
+
+static int bcm2835_get_temp_or_max(struct thermal_zone_device *thermal_dev, unsigned long *temp, unsigned tag_id)
+{
+ int result = -1, retry = 3;
+ print_debug("IN");
+
+ *temp = 0;
+ while (result != 0 && retry-- > 0) {
+ /* 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 = tag_id;
+
+ /* send the message */
+ result = bcm_mailbox_property(&bcm2835_data.msg, sizeof bcm2835_data.msg);
+ print_debug("Got %stemperature as %u (%d,%x)\n", tag_id==VC_TAG_GET_MAX_TEMP ? "max ":"", (uint)bcm2835_data.msg.tag.val, result, bcm2835_data.msg.request_code);
+ if (!(bcm2835_data.msg.request_code & 0x80000000))
+ result = -1;
+ }
+
+ /* check if it was all ok and return the rate in milli degrees C */
+ if (result == 0)
+ *temp = (uint)bcm2835_data.msg.tag.val;
+ else
+ print_err("Failed to get temperature! (%x:%d)\n", tag_id, result);
+ print_debug("OUT");
+ return result;
+}
+
+static int bcm2835_get_temp(struct thermal_zone_device *thermal_dev, unsigned long *temp)
+{
+ return bcm2835_get_temp_or_max(thermal_dev, temp, VC_TAG_GET_TEMP);
+}
+
+static int bcm2835_get_max_temp(struct thermal_zone_device *thermal_dev, int trip_num, unsigned long *temp)
+{
+ return bcm2835_get_temp_or_max(thermal_dev, temp, VC_TAG_GET_MAX_TEMP);
+}
+
+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, 0, NULL, &ops, NULL, 0, 0)))
+ {
+ 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);
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -169,4 +169,11 @@ config INTEL_POWERCLAMP
enforce idle time which results in more package C-state residency. The
user interface is exposed via generic thermal framework.
+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
+
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -23,4 +23,5 @@ obj-$(CONFIG_DB8500_THERMAL) += db8500_t
obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o
obj-$(CONFIG_DB8500_CPUFREQ_COOLING) += db8500_cpufreq_cooling.o
obj-$(CONFIG_INTEL_POWERCLAMP) += intel_powerclamp.o
+obj-$(CONFIG_THERMAL_BCM2835) += bcm2835-thermal.o
|
