This adds the support for reading out temperature from Broadcom bcm281xx
SoCs.

Signed-off-by: Wendy Ng <wendy...@broadcom.com>
Reviewed-by: Markus Mayer <mma...@broadcom.com>
Reviewed-by: Christian Daudt <c...@broadcom.com>
---
 .../bindings/thermal/bcm-kona-thermal.txt          |   18 +++
 drivers/thermal/Kconfig                            |   10 ++
 drivers/thermal/Makefile                           |    1 +
 drivers/thermal/bcm_thermal.c                      |  170 ++++++++++++++++++++
 4 files changed, 199 insertions(+)
 create mode 100644 
Documentation/devicetree/bindings/thermal/bcm-kona-thermal.txt
 create mode 100644 drivers/thermal/bcm_thermal.c

diff --git a/Documentation/devicetree/bindings/thermal/bcm-kona-thermal.txt 
b/Documentation/devicetree/bindings/thermal/bcm-kona-thermal.txt
new file mode 100644
index 0000000..acca99e
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/bcm-kona-thermal.txt
@@ -0,0 +1,18 @@
+* Broadcom Kona Thermal Management Unit
+
+This version is for the BCM281xx family of SoCs.
+
+Required properties:
+- compatible : "brcm,bcm11351-thermal", "brcm,kona-thermal"
+- reg : Address range of the thermal register
+- thermal-name: this entry must be specified and it will be passed into
+thermal_zone_device_register().  This name will also be reported under Hwmon
+sysfs 'name' attribute.
+
+Example:
+       thermal@34008000 {
+               compatible = "brcm,bcm11351-thermal", "brcm,kona-thermal";
+               reg = <0x34008000 0x0024>;
+               thermal-name = "bcm_kona_therm";
+               status = "disabled";
+       };
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index dbfc390..6a5341c 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -134,6 +134,16 @@ config KIRKWOOD_THERMAL
          Support for the Kirkwood thermal sensor driver into the Linux thermal
          framework. Only kirkwood 88F6282 and 88F6283 have this sensor.
 
+config BCM_THERMAL
+       tristate "Temperature sensor on Broadcom BCM281xx family of SoCs"
+       depends on ARCH_BCM_MOBILE
+       default y
+       help
+         If you say yes here you get support for TMU (Thermal Management
+         Unit) on Broadcom BCM281xx family of SoCs. This provides thermal
+         monitoring of CPU clusters, graphics, and SoC glue, but does not
+         include monitoring of charger temperature.
+
 config DOVE_THERMAL
        tristate "Temperature sensor on Marvell Dove SoCs"
        depends on ARCH_DOVE
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 584b363..3ea8c1c 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_SPEAR_THERMAL)   += spear_thermal.o
 obj-$(CONFIG_RCAR_THERMAL)     += rcar_thermal.o
 obj-$(CONFIG_KIRKWOOD_THERMAL)  += kirkwood_thermal.o
 obj-y                          += samsung/
+obj-$(CONFIG_BCM_THERMAL)       += bcm_thermal.o
 obj-$(CONFIG_DOVE_THERMAL)     += dove_thermal.o
 obj-$(CONFIG_DB8500_THERMAL)   += db8500_thermal.o
 obj-$(CONFIG_ARMADA_THERMAL)   += armada_thermal.o
diff --git a/drivers/thermal/bcm_thermal.c b/drivers/thermal/bcm_thermal.c
new file mode 100644
index 0000000..131d3c4
--- /dev/null
+++ b/drivers/thermal/bcm_thermal.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright 2013 Broadcom Corporation.
+ *
+ * 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 (the "GPL").
+ *
+ * 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.
+ *
+ * A copy of the GPL is available at 
http://www.broadcom.com/licenses/GPLv2.php,
+ * or by writing to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+/**
+*  Broadcom Thermal Management Unit - bcm_tmu
+*/
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/thermal.h>
+#include <linux/of.h>
+
+/* From TMON Register Database */
+#define TMON_TEMP_VAL_OFFSET                   0x0000001c
+#define TMON_TEMP_VAL_TEMP_VAL_SHIFT           0
+#define TMON_TEMP_VAL_TEMP_VAL_MASK            0x000003ff
+
+/* Broadcom Thermal Zone Device Structure */
+struct bcm_thermal_zone_priv {
+       char name[THERMAL_NAME_LENGTH];
+       void __iomem *base;
+};
+
+/* Temperature conversion function for TMON block */
+static long raw_to_mcelsius(u32 raw)
+{
+       /*
+        * According to Broadcom internal Analog Module Specification
+        * the formula for converting TMON block output to temperature in
+        * degree Celsius is:
+        *      T = 428 - (0.561 * raw)
+        * Note: the valid operating range for the TMON block is -40C to 125C
+        */
+       return 428000 - (561 * (long)raw);
+}
+
+/* Get temperature callback function for thermal zone */
+static int bcm_get_temp(struct thermal_zone_device *thermal,
+                       unsigned long *temp)
+{
+       u32 raw;
+       long mcelsius;
+       struct bcm_thermal_zone_priv *priv = thermal->devdata;
+
+       if (!priv) {
+               pr_err("%s: thermal zone number %d devdata not initialized.\n",
+                       __func__, thermal->id);
+               return -EINVAL;
+       }
+
+       raw = (readl(priv->base + TMON_TEMP_VAL_OFFSET)
+               & TMON_TEMP_VAL_TEMP_VAL_MASK) >> TMON_TEMP_VAL_TEMP_VAL_SHIFT;
+
+       pr_debug("%s: thermal zone number %d raw temp 0x%x\n", __func__,
+               thermal->id, raw);
+
+       mcelsius = raw_to_mcelsius(raw);
+
+       /*
+        * Since 'mcelsius' might be negative, we need to limit it to smallest
+        * unsigned value before returning it to thermal framework.
+        */
+       if (mcelsius < 0)
+               *temp = 0;
+       else
+               *temp = mcelsius;
+
+       pr_debug("%s: thermal zone number %d final temp %d\n", __func__,
+               thermal->id, (int) *temp);
+
+       return 0;
+}
+
+/* Operation callback functions for thermal zone */
+static struct thermal_zone_device_ops bcm_dev_ops = {
+       .get_temp = bcm_get_temp,
+};
+
+static const struct of_device_id bcm_tmu_match_table[] = {
+       { .compatible = "brcm,kona-thermal" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, bcm_tmu_match_table);
+
+static int bcm_tmu_probe(struct platform_device *pdev)
+{
+       struct thermal_zone_device *thermal = NULL;
+       struct bcm_thermal_zone_priv *priv;
+       struct resource *res;
+       const char *str;
+
+       priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv) {
+               dev_err(&pdev->dev, "Failed to malloc priv.\n");
+               return -ENOMEM;
+       }
+
+       /* Obtain the tmu name from device tree file */
+       if (of_property_read_string(pdev->dev.of_node, "thermal-name",
+                       &str) == 0) {
+               strlcpy(priv->name, str, sizeof(priv->name));
+       } else {
+               dev_err(&pdev->dev, "Failed to get thermal-name from DT.\n");
+               return -EINVAL;
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       priv->base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(priv->base))
+               return PTR_ERR(priv->base);
+
+       thermal = thermal_zone_device_register(priv->name, 0, 0, priv,
+                                               &bcm_dev_ops, NULL, 0, 0);
+       if (IS_ERR(thermal)) {
+               dev_err(&pdev->dev,
+                       "Failed to register Broadcom thermal zone device.\n");
+               return PTR_ERR(thermal);
+       }
+
+       platform_set_drvdata(pdev, thermal);
+
+       dev_info(&pdev->dev, "Broadcom Thermal Monitor Initialized.\n");
+
+       return 0;
+}
+
+static int bcm_tmu_remove(struct platform_device *pdev)
+{
+       struct thermal_zone_device *broadcom_thermal =
+               platform_get_drvdata(pdev);
+
+       thermal_zone_device_unregister(broadcom_thermal);
+
+       dev_info(&pdev->dev, "Broadcom Thermal Monitor Uninitialized.\n");
+
+       return 0;
+}
+
+static struct platform_driver bcm_tmu_driver = {
+       .driver = {
+               .name = "bcm-thermal",
+               .owner = THIS_MODULE,
+               .of_match_table = bcm_tmu_match_table,
+       },
+       .probe = bcm_tmu_probe,
+       .remove = bcm_tmu_remove,
+};
+
+module_platform_driver(bcm_tmu_driver);
+
+MODULE_DESCRIPTION("Broadcom Thermal Driver");
+MODULE_AUTHOR("Broadcom");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:bcm-thermal");
-- 
1.7.9.5


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