From: Vincenzo Frascino <[email protected]>
ST's SPEAr13xx machines are based on CortexA9 ARM processors. These
machines contain a thermal sensor for junction temperature monitoring.
This patch adds support for this thermal sensor in existing thermal
framework.
Signed-off-by: Vincenzo Frascino <[email protected]>
Signed-off-by: Viresh Kumar <[email protected]>
---
drivers/thermal/Kconfig | 7 +
drivers/thermal/Makefile | 1 +
drivers/thermal/spear_thermal.c | 205 +++++++++++++++++++++++++++
include/linux/platform_data/spear_thermal.h | 26 ++++
4 files changed, 239 insertions(+), 0 deletions(-)
create mode 100644 drivers/thermal/spear_thermal.c
create mode 100644 include/linux/platform_data/spear_thermal.h
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index f7f71b2..2633fe0 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -18,3 +18,10 @@ config THERMAL_HWMON
depends on THERMAL
depends on HWMON=y || HWMON=THERMAL
default y
+
+config SPEAR_THERMAL
+ bool "SPEAr thermal sensor driver"
+ depends on THERMAL
+ help
+ Enable this to plug the SPEAr thermal sensor driver into the Linux
+ thermal framework
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 31108a0..a9fff0b 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_THERMAL) += thermal_sys.o
+obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o
\ No newline at end of file
diff --git a/drivers/thermal/spear_thermal.c b/drivers/thermal/spear_thermal.c
new file mode 100644
index 0000000..d819b3c
--- /dev/null
+++ b/drivers/thermal/spear_thermal.c
@@ -0,0 +1,205 @@
+/*
+ * SPEAr thermal driver.
+ *
+ * Copyright (C) 2011-2012 ST Microelectronics
+ * Author: Vincenzo Frascino <[email protected]>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/spear_thermal.h>
+#include <linux/thermal.h>
+
+#define MD_FACTOR 1000
+
+/* SPEAr Thermal Sensor Dev Structure */
+struct spear_thermal_dev {
+ /* pointer to base address of the thermal sensor */
+ void __iomem *thermal_base;
+ /* clk structure */
+ struct clk *clk;
+ /* pointer to thermal flags */
+ unsigned int flags;
+};
+
+static inline int thermal_get_temp(struct thermal_zone_device *thermal,
+ unsigned long *temp)
+{
+ struct spear_thermal_dev *stdev = thermal->devdata;
+
+ /*
+ * Data are ready to be read after 628 usec from POWERDOWN signal
+ * (PDN) = 1
+ */
+ *temp = (readl(stdev->thermal_base) & 0x7F) * MD_FACTOR;
+ return 0;
+}
+
+static struct thermal_zone_device_ops ops = {
+ .get_temp = thermal_get_temp,
+};
+
+#ifdef CONFIG_PM
+static int spear_thermal_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
+ struct spear_thermal_dev *stdev = spear_thermal->devdata;
+ unsigned int actual_mask = 0;
+
+ /* Disable SPEAr Thermal Sensor */
+ actual_mask = readl(stdev->thermal_base);
+ writel(actual_mask & ~stdev->flags, stdev->thermal_base);
+
+ clk_disable(stdev->clk);
+ dev_info(dev, "Suspended.\n");
+
+ return 0;
+}
+
+static int spear_thermal_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
+ struct spear_thermal_dev *stdev = spear_thermal->devdata;
+ unsigned int actual_mask = 0;
+ int ret = 0;
+
+ ret = clk_enable(stdev->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Can't enable clock\n");
+ return ret;
+ }
+
+ /* Enable SPEAr Thermal Sensor */
+ actual_mask = readl(stdev->thermal_base);
+ writel(actual_mask | stdev->flags, stdev->thermal_base);
+
+ dev_info(dev, "Resumed.\n");
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend,
+ spear_thermal_resume);
+
+static int spear_thermal_probe(struct platform_device *pdev)
+{
+ struct thermal_zone_device *spear_thermal = NULL;
+ struct spear_thermal_dev *stdev;
+ struct spear_thermal_pdata *pdata;
+ int ret = 0;
+ struct resource *stres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!stres) {
+ dev_err(&pdev->dev, "memory resource missing\n");
+ return -ENODEV;
+ }
+
+ pdata = dev_get_platdata(&pdev->dev);
+ if (!pdata) {
+ dev_err(&pdev->dev, "platform data is NULL\n");
+ return -EINVAL;
+ }
+
+ stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);
+ if (!stdev) {
+ dev_err(&pdev->dev, "kzalloc fail\n");
+ return -ENOMEM;
+ }
+
+ /* Enable thermal sensor */
+ stdev->thermal_base = devm_ioremap(&pdev->dev, stres->start,
+ resource_size(stres));
+ if (!stdev->thermal_base) {
+ dev_err(&pdev->dev, "ioremap failed\n");
+ return -ENOMEM;
+ }
+
+ stdev->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(stdev->clk)) {
+ dev_err(&pdev->dev, "Can't get clock\n");
+ return PTR_ERR(stdev->clk);
+ }
+
+ ret = clk_enable(stdev->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Can't enable clock\n");
+ goto put_clk;
+ }
+
+ stdev->flags = pdata->thermal_flags;
+ writel(stdev->flags, stdev->thermal_base);
+
+ spear_thermal = thermal_zone_device_register("spear_thermal", 0,
+ stdev, &ops, 0, 0, 0, 0);
+ if (!spear_thermal) {
+ dev_err(&pdev->dev, "thermal zone device is NULL\n");
+ ret = -EINVAL;
+ goto disable_clk;
+ }
+
+ platform_set_drvdata(pdev, spear_thermal);
+
+ dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%x.\n",
+ (unsigned int)stdev->thermal_base);
+
+ return 0;
+
+disable_clk:
+ clk_disable(stdev->clk);
+put_clk:
+ clk_put(stdev->clk);
+
+ return ret;
+}
+
+static int spear_thermal_exit(struct platform_device *pdev)
+{
+ unsigned int actual_mask = 0;
+ struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
+ struct spear_thermal_dev *stdev = spear_thermal->devdata;
+
+ thermal_zone_device_unregister(spear_thermal);
+ platform_set_drvdata(pdev, NULL);
+
+ /* Disable SPEAr Thermal Sensor */
+ actual_mask = readl(stdev->thermal_base);
+ writel(actual_mask & ~stdev->flags, stdev->thermal_base);
+
+ clk_disable(stdev->clk);
+ clk_put(stdev->clk);
+
+ return 0;
+}
+
+static struct platform_driver spear_thermal_driver = {
+ .probe = spear_thermal_probe,
+ .remove = spear_thermal_exit,
+ .driver = {
+ .name = "spear_thermal",
+ .owner = THIS_MODULE,
+ .pm = &spear_thermal_pm_ops,
+ },
+};
+
+module_platform_driver(spear_thermal_driver);
+
+MODULE_AUTHOR("Vincenzo Frascino <[email protected]>");
+MODULE_DESCRIPTION("SPEAr thermal driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/platform_data/spear_thermal.h b/include/linux/platform_data/spear_thermal.h
new file mode 100644
index 0000000..724f2e1
--- /dev/null
+++ b/include/linux/platform_data/spear_thermal.h
@@ -0,0 +1,26 @@
+/*
+ * SPEAr thermal driver platform data.
+ *
+ * Copyright (C) 2011-2012 ST Microelectronics
+ * Author: Vincenzo Frascino <[email protected]>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+#ifndef SPEAR_THERMAL_H
+#define SPEAR_THERMAL_H
+
+/* SPEAr Thermal Sensor Platform Data */
+struct spear_thermal_pdata {
+ /* flags used to enable thermal sensor */
+ unsigned int thermal_flags;
+};
+
+#endif /* SPEAR_THERMAL_H */
--
1.7.8.110.g4cb5d
On Fri, 24 Feb 2012 12:57:38 +0530
Viresh Kumar <[email protected]> wrote:
> From: Vincenzo Frascino <[email protected]>
>
> ST's SPEAr13xx machines are based on CortexA9 ARM processors. These
> machines contain a thermal sensor for junction temperature monitoring.
>
> This patch adds support for this thermal sensor in existing thermal
> framework.
>
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -18,3 +18,10 @@ config THERMAL_HWMON
> depends on THERMAL
> depends on HWMON=y || HWMON=THERMAL
> default y
> +
> +config SPEAR_THERMAL
> + bool "SPEAr thermal sensor driver"
> + depends on THERMAL
> + help
> + Enable this to plug the SPEAr thermal sensor driver into the Linux
> + thermal framework
The driver can be compiled for all architectures which support
CONFIG_THERMAL. This includes x86_64. Was that intended?
I don't think it's necessarily a bad thing: it gives the driver a lot
more compilation coverage and exposes bugs such as
drivers/thermal/spear_thermal.c: In function 'spear_thermal_probe':
drivers/thermal/spear_thermal.c:159: warning: cast from pointer to integer of different size
--- a/drivers/thermal/spear_thermal.c~thermal-add-support-for-thermal-sensor-present-on-spear13xx-machines-fix
+++ a/drivers/thermal/spear_thermal.c
@@ -156,8 +156,8 @@ static int spear_thermal_probe(struct pl
platform_set_drvdata(pdev, spear_thermal);
- dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%x.\n",
- (unsigned int)stdev->thermal_base);
+ dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%p.\n",
+ stdev->thermal_base);
return 0;
but I do wonder if this was intentional.
On Fri, 24 Feb 2012 19:30:54 -0800
viresh kumar <[email protected]> wrote:
> On Feb 25, 2012 1:32 AM, "Andrew Morton" <[email protected]> wrote:
> >
>
> > The driver can be compiled for all architectures which support
> > CONFIG_THERMAL. This includes x86_64. Was that intended?
> >
>
> No.
>
> > I don't think it's necessarily a bad thing:
>
> Ya we thought about removing spear_* from the driver. But the hardware
> looked a bit proprietary.
I don't really understand this reply. Does it mean that you will be
updating the Kconfig logic?