lkml.org 
[lkml]   [2013]   [Sep]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 1/3] thermal: bcm281xx: Add thermal driver
Date
This adds the support for reading out temperature from Broadcom bcm281xx
SoCs.

Signed-off-by: Wendy Ng <wendy.ng@broadcom.com>
Reviewed-by: Markus Mayer <mmayer@broadcom.com>
Reviewed-by: Christian Daudt <csd@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



\
 
 \ /
  Last update: 2013-09-28 01:01    [W:0.072 / U:6.556 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site