* [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU
@ 2011-08-31 8:56 Donggeun Kim
2011-09-01 5:22 ` Guenter Roeck
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Donggeun Kim @ 2011-08-31 8:56 UTC (permalink / raw)
To: lm-sensors
Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
Changes for v4
- added comment for unit of threshold and trigger_levels
- cleaned up code
Changes for v3
- cleaned up redundant code
- added mutex
- changed error codes
Changes for v2
- added six attributes for alarms
- changed error code of EAGAIN
- changed initialize function to return error code
Documentation/hwmon/exynos4_tmu | 81 +++++
drivers/hwmon/Kconfig | 10 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/exynos4_tmu.c | 533 +++++++++++++++++++++++++++++
include/linux/platform_data/exynos4_tmu.h | 83 +++++
5 files changed, 708 insertions(+), 0 deletions(-)
create mode 100644 Documentation/hwmon/exynos4_tmu
create mode 100644 drivers/hwmon/exynos4_tmu.c
create mode 100644 include/linux/platform_data/exynos4_tmu.h
diff --git a/Documentation/hwmon/exynos4_tmu b/Documentation/hwmon/exynos4_tmu
new file mode 100644
index 0000000..7fe12c1
--- /dev/null
+++ b/Documentation/hwmon/exynos4_tmu
@@ -0,0 +1,81 @@
+Kernel driver exynos4_tmu
+========+
+Supported chips:
+* ARM SAMSUNG EXYNOS4 series of SoC
+ Prefix: 'exynos4-tmu'
+ Datasheet: Not publicly available
+
+Authors: Donggeun Kim <dg77.kim@samsung.com>
+
+Description
+-----------
+
+This driver allows to read temperature inside SAMSUNG EXYNOS4 series of SoC.
+
+The chip only exposes the measured 8-bit temperature code value
+through a register.
+Temperature can be taken from the temperature code.
+There are three equations converting from temperature to temperature code.
+
+The three equations are:
+ 1. Two point trimming
+ Tc = (T - 25) * (TI2 - TI1) / (85 - 25) + TI1
+
+ 2. One point trimming
+ Tc = T + TI1 - 25
+
+ 3. No trimming
+ Tc = T + 50
+
+ Tc: Temperature code, T: Temperature,
+ TI1: Trimming info for 25 degree Celsius (stored at TRIMINFO register)
+ Temperature code measured at 25 degree Celsius which is unchanged
+ TI2: Trimming info for 85 degree Celsius (stored at TRIMINFO register)
+ Temperature code measured at 85 degree Celsius which is unchanged
+
+TMU(Thermal Management Unit) in EXYNOS4 generates interrupt
+when temperature exceeds pre-defined levels.
+The maximum number of configurable threshold is four.
+The threshold levels are defined as follows:
+ Level_0: current temperature > trigger_level_0 + threshold
+ Level_1: current temperature > trigger_level_1 + threshold
+ Level_2: current temperature > trigger_level_2 + threshold
+ Level_3: current temperature > trigger_level_3 + threshold
+
+ The threshold and each trigger_level are set
+ through the corresponding registers.
+
+When an interrupt occurs, this driver notify user space of
+one of four threshold levels for the interrupt
+through kobject_uevent_env and sysfs_notify functions.
+Although an interrupt condition for level_0 can be set,
+it is not notified to user space through sysfs_notify function.
+
+Sysfs Interface
+---------------
+name name of the temperature sensor
+ RO
+
+temp1_input temperature
+ RO
+
+temp1_max temperature for level_1 interrupt
+ RO
+
+temp1_crit temperature for level_2 interrupt
+ RO
+
+temp1_emergency temperature for level_3 interrupt
+ RO
+
+temp1_max_alarm alarm for level_1 interrupt
+ RO
+
+temp1_crit_alarm
+ alarm for level_2 interrupt
+ RO
+
+temp1_emergency_alarm
+ alarm for level_3 interrupt
+ RO
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 0b62c3c..c6fb761 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -303,6 +303,16 @@ config SENSORS_DS1621
This driver can also be built as a module. If so, the module
will be called ds1621.
+config SENSORS_EXYNOS4_TMU
+ tristate "Temperature sensor on Samsung EXYNOS4"
+ depends on EXYNOS4_DEV_TMU
+ help
+ If you say yes here you get support for TMU (Thermal Managment
+ Unit) on SAMSUNG EXYNOS4 series of SoC.
+
+ This driver can also be built as a module. If so, the module
+ will be called exynos4-tmu.
+
config SENSORS_I5K_AMB
tristate "FB-DIMM AMB temperature sensor on Intel 5000 series chipsets"
depends on PCI && EXPERIMENTAL
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 3c9ccef..dbd8963 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -47,6 +47,7 @@ obj-$(CONFIG_SENSORS_DS1621) += ds1621.o
obj-$(CONFIG_SENSORS_EMC1403) += emc1403.o
obj-$(CONFIG_SENSORS_EMC2103) += emc2103.o
obj-$(CONFIG_SENSORS_EMC6W201) += emc6w201.o
+obj-$(CONFIG_SENSORS_EXYNOS4_TMU) += exynos4_tmu.o
obj-$(CONFIG_SENSORS_F71805F) += f71805f.o
obj-$(CONFIG_SENSORS_F71882FG) += f71882fg.o
obj-$(CONFIG_SENSORS_F75375S) += f75375s.o
diff --git a/drivers/hwmon/exynos4_tmu.c b/drivers/hwmon/exynos4_tmu.c
new file mode 100644
index 0000000..9d1002a
--- /dev/null
+++ b/drivers/hwmon/exynos4_tmu.c
@@ -0,0 +1,533 @@
+/*
+ * exynos4_tmu.c - Samsung EXYNOS4 TMU (Thermal Management Unit)
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * Donggeun Kim <dg77.kim@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/workqueue.h>
+#include <linux/sysfs.h>
+#include <linux/kobject.h>
+#include <linux/io.h>
+#include <linux/mutex.h>
+
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#include <linux/platform_data/exynos4_tmu.h>
+
+#define EXYNOS4_TMU_REG_TRIMINFO 0x0
+#define EXYNOS4_TMU_REG_CONTROL 0x20
+#define EXYNOS4_TMU_REG_STATUS 0x28
+#define EXYNOS4_TMU_REG_CURRENT_TEMP 0x40
+#define EXYNOS4_TMU_REG_THRESHOLD_TEMP 0x44
+#define EXYNOS4_TMU_REG_TRIG_LEVEL0 0x50
+#define EXYNOS4_TMU_REG_TRIG_LEVEL1 0x54
+#define EXYNOS4_TMU_REG_TRIG_LEVEL2 0x58
+#define EXYNOS4_TMU_REG_TRIG_LEVEL3 0x5C
+#define EXYNOS4_TMU_REG_PAST_TEMP0 0x60
+#define EXYNOS4_TMU_REG_PAST_TEMP1 0x64
+#define EXYNOS4_TMU_REG_PAST_TEMP2 0x68
+#define EXYNOS4_TMU_REG_PAST_TEMP3 0x6C
+#define EXYNOS4_TMU_REG_INTEN 0x70
+#define EXYNOS4_TMU_REG_INTSTAT 0x74
+#define EXYNOS4_TMU_REG_INTCLEAR 0x78
+
+#define EXYNOS4_TMU_GAIN_SHIFT 8
+#define EXYNOS4_TMU_REF_VOLTAGE_SHIFT 24
+
+#define EXYNOS4_TMU_TRIM_TEMP_MASK 0xff
+#define EXYNOS4_TMU_CORE_ON 3
+#define EXYNOS4_TMU_CORE_OFF 2
+#define EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET 50
+#define EXYNOS4_TMU_TRIG_LEVEL0_MASK 0x1
+#define EXYNOS4_TMU_TRIG_LEVEL1_MASK 0x10
+#define EXYNOS4_TMU_TRIG_LEVEL2_MASK 0x100
+#define EXYNOS4_TMU_TRIG_LEVEL3_MASK 0x1000
+#define EXYNOS4_TMU_INTCLEAR_VAL 0x1111
+
+struct exynos4_tmu_data {
+ struct exynos4_tmu_platform_data *pdata;
+ struct device *hwmon_dev;
+ struct resource *mem;
+ void __iomem *base;
+ int irq;
+ struct work_struct irq_work;
+ struct mutex lock;
+ struct clk *clk;
+ unsigned int interrupt_stat;
+ u8 temp_error1, temp_error2;
+};
+
+/*
+ * TMU treats temperature as a mapped temperature code.
+ * The temperature is converted differently depending on the calibration type.
+ */
+static u8 translate_temp_to_code(struct exynos4_tmu_data *data, u8 temp)
+{
+ struct exynos4_tmu_platform_data *pdata = data->pdata;
+ unsigned int temp_code;
+
+ switch (pdata->cal_type) {
+ case TYPE_TWO_POINT_TRIMMING:
+ temp_code = (temp - 25) *
+ (data->temp_error2 - data->temp_error1) /
+ (85 - 25) + data->temp_error1;
+ break;
+ case TYPE_ONE_POINT_TRIMMING:
+ temp_code = temp + data->temp_error1 - 25;
+ break;
+ default:
+ temp_code = temp + EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
+ break;
+ }
+
+ return temp_code;
+}
+
+/*
+ * Calculate a temperature value from a temperature code.
+ * The unit of the temperature is degree Celsius.
+ */
+static u8 translate_code_to_temp(struct exynos4_tmu_data *data, u8 temp_code)
+{
+ struct exynos4_tmu_platform_data *pdata = data->pdata;
+ unsigned int temp;
+
+ switch (pdata->cal_type) {
+ case TYPE_TWO_POINT_TRIMMING:
+ temp = (temp_code - data->temp_error1) * (85 - 25) /
+ (data->temp_error2 - data->temp_error1) + 25;
+ break;
+ case TYPE_ONE_POINT_TRIMMING:
+ temp = temp_code - data->temp_error1 + 25;
+ break;
+ default:
+ temp = temp_code - EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
+ break;
+ }
+
+ return temp;
+}
+
+static int exynos4_tmu_initialize(struct platform_device *pdev)
+{
+ struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
+ struct exynos4_tmu_platform_data *pdata = data->pdata;
+ unsigned int status, trim_info;
+ u8 threshold_code;
+
+ mutex_lock(&data->lock);
+ clk_enable(data->clk);
+
+ status = readb(data->base + EXYNOS4_TMU_REG_STATUS);
+ if (!status) {
+ clk_disable(data->clk);
+ mutex_unlock(&data->lock);
+ return -EBUSY;
+ }
+
+ /* Save trimming info in order to perform calibration */
+ trim_info = readl(data->base + EXYNOS4_TMU_REG_TRIMINFO);
+ data->temp_error1 = trim_info & EXYNOS4_TMU_TRIM_TEMP_MASK;
+ data->temp_error2 = ((trim_info >> 8) & EXYNOS4_TMU_TRIM_TEMP_MASK);
+
+ /* Write temperature code for threshold */
+ threshold_code = translate_temp_to_code(data, pdata->threshold);
+ writeb(threshold_code,
+ data->base + EXYNOS4_TMU_REG_THRESHOLD_TEMP);
+
+ writeb(pdata->trigger_levels[0],
+ data->base + EXYNOS4_TMU_REG_TRIG_LEVEL0);
+ writeb(pdata->trigger_levels[1],
+ data->base + EXYNOS4_TMU_REG_TRIG_LEVEL1);
+ writeb(pdata->trigger_levels[2],
+ data->base + EXYNOS4_TMU_REG_TRIG_LEVEL2);
+ writeb(pdata->trigger_levels[3],
+ data->base + EXYNOS4_TMU_REG_TRIG_LEVEL3);
+
+ writel(EXYNOS4_TMU_INTCLEAR_VAL,
+ data->base + EXYNOS4_TMU_REG_INTCLEAR);
+
+ clk_disable(data->clk);
+ mutex_unlock(&data->lock);
+
+ return 0;
+}
+
+static void exynos4_tmu_control(struct platform_device *pdev, bool on)
+{
+ struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
+ struct exynos4_tmu_platform_data *pdata = data->pdata;
+ unsigned int con, interrupt_en;
+
+ mutex_lock(&data->lock);
+ clk_enable(data->clk);
+
+ interrupt_en = pdata->trigger_level3_en << 12 |
+ pdata->trigger_level2_en << 8 |
+ pdata->trigger_level1_en << 4 |
+ pdata->trigger_level0_en;
+
+ con = pdata->reference_voltage << EXYNOS4_TMU_REF_VOLTAGE_SHIFT |
+ pdata->gain << EXYNOS4_TMU_GAIN_SHIFT;
+ if (on)
+ con |= EXYNOS4_TMU_CORE_ON;
+ else {
+ con |= EXYNOS4_TMU_CORE_OFF;
+ interrupt_en = 0; /* Disable all interrupts */
+ }
+ writel(interrupt_en, data->base + EXYNOS4_TMU_REG_INTEN);
+ writel(con, data->base + EXYNOS4_TMU_REG_CONTROL);
+
+ clk_disable(data->clk);
+ mutex_unlock(&data->lock);
+}
+
+static int exynos4_tmu_read(struct exynos4_tmu_data *data)
+{
+ u8 temp_code, temp;
+
+ mutex_lock(&data->lock);
+ clk_enable(data->clk);
+
+ temp_code = readb(data->base + EXYNOS4_TMU_REG_CURRENT_TEMP);
+ if (!temp_code) {
+ clk_disable(data->clk);
+ mutex_unlock(&data->lock);
+ return -ENODATA;
+ }
+ temp = translate_code_to_temp(data, temp_code);
+
+ clk_disable(data->clk);
+ mutex_unlock(&data->lock);
+
+ return temp;
+}
+
+static void exynos4_tmu_work(struct work_struct *work)
+{
+ struct exynos4_tmu_data *data = container_of(work,
+ struct exynos4_tmu_data, irq_work);
+ char *envp[2];
+
+ mutex_lock(&data->lock);
+ clk_enable(data->clk);
+
+ data->interrupt_stat = readl(data->base + EXYNOS4_TMU_REG_INTSTAT);
+
+ writel(EXYNOS4_TMU_INTCLEAR_VAL, data->base + EXYNOS4_TMU_REG_INTCLEAR);
+
+ if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL3_MASK) {
+ envp[0] = "TRIG_LEVEL=3";
+ sysfs_notify(&data->hwmon_dev->kobj, NULL,
+ "temp1_emergency_alarm");
+ } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL2_MASK) {
+ envp[0] = "TRIG_LEVEL=2";
+ sysfs_notify(&data->hwmon_dev->kobj, NULL,
+ "temp1_crit_alarm");
+ } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL1_MASK) {
+ envp[0] = "TRIG_LEVEL=1";
+ sysfs_notify(&data->hwmon_dev->kobj, NULL, "temp1_max_alarm");
+ } else
+ envp[0] = "TRIG_LEVEL=0";
+ envp[1] = NULL;
+
+ kobject_uevent_env(&data->hwmon_dev->kobj, KOBJ_CHANGE, envp);
+
+ enable_irq(data->irq);
+
+ clk_disable(data->clk);
+ mutex_unlock(&data->lock);
+}
+
+static irqreturn_t exynos4_tmu_irq(int irq, void *id)
+{
+ struct exynos4_tmu_data *data = id;
+
+ disable_irq_nosync(irq);
+ schedule_work(&data->irq_work);
+
+ return IRQ_HANDLED;
+}
+
+static ssize_t exynos4_tmu_show_name(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "exynos4-tmu\n");
+}
+
+static ssize_t exynos4_tmu_show_temp(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct exynos4_tmu_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ ret = exynos4_tmu_read(data);
+ if (ret < 0)
+ return ret;
+
+ /* convert from degree Celsius to millidegree Celsius */
+ return sprintf(buf, "%d\n", ret * 1000);
+}
+
+static ssize_t exynos4_tmu_show_alarm(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct exynos4_tmu_data *data = dev_get_drvdata(dev);
+ struct exynos4_tmu_platform_data *pdata = data->pdata;
+ int temp;
+ unsigned int trigger_level;
+
+ temp = exynos4_tmu_read(data);
+ if (temp < 0)
+ return temp;
+
+ trigger_level = pdata->threshold + pdata->trigger_levels[attr->index];
+
+ return sprintf(buf, "%d\n", temp > trigger_level ? 1 : 0);
+}
+
+static ssize_t exynos4_tmu_show_level(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct exynos4_tmu_data *data = dev_get_drvdata(dev);
+ struct exynos4_tmu_platform_data *pdata = data->pdata;
+ unsigned int temp = pdata->threshold +
+ pdata->trigger_levels[attr->index];
+
+ return sprintf(buf, "%d\n", temp * 1000);
+}
+
+static DEVICE_ATTR(name, S_IRUGO, exynos4_tmu_show_name, NULL);
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, exynos4_tmu_show_temp, NULL, 0);
+
+static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,
+ exynos4_tmu_show_alarm, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO,
+ exynos4_tmu_show_alarm, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO,
+ exynos4_tmu_show_alarm, NULL, 3);
+
+static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, exynos4_tmu_show_level, NULL, 1);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, exynos4_tmu_show_level, NULL, 2);
+static SENSOR_DEVICE_ATTR(temp1_emergency, S_IRUGO,
+ exynos4_tmu_show_level, NULL, 3);
+
+static struct attribute *exynos4_tmu_attributes[] = {
+ &dev_attr_name.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit.dev_attr.attr,
+ &sensor_dev_attr_temp1_emergency.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group exynos4_tmu_attr_group = {
+ .attrs = exynos4_tmu_attributes,
+};
+
+static int __devinit exynos4_tmu_probe(struct platform_device *pdev)
+{
+ struct exynos4_tmu_data *data;
+ struct exynos4_tmu_platform_data *pdata = pdev->dev.platform_data;
+ int ret;
+
+ if (!pdata) {
+ dev_err(&pdev->dev, "No platform init data supplied.\n");
+ return -ENODEV;
+ }
+
+ data = kzalloc(sizeof(struct exynos4_tmu_data), GFP_KERNEL);
+ if (!data) {
+ dev_err(&pdev->dev, "Failed to allocate driver structure\n");
+ return -ENOMEM;
+ }
+
+ data->irq = platform_get_irq(pdev, 0);
+ if (data->irq < 0) {
+ ret = data->irq;
+ dev_err(&pdev->dev, "Failed to get platform irq\n");
+ goto err_free;
+ }
+
+ INIT_WORK(&data->irq_work, exynos4_tmu_work);
+
+ data->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!data->mem) {
+ ret = -ENOENT;
+ dev_err(&pdev->dev, "Failed to get platform resource\n");
+ goto err_free;
+ }
+
+ data->mem = request_mem_region(data->mem->start,
+ resource_size(data->mem), pdev->name);
+ if (!data->mem) {
+ ret = -ENODEV;
+ dev_err(&pdev->dev, "Failed to request memory region\n");
+ goto err_free;
+ }
+
+ data->base = ioremap(data->mem->start, resource_size(data->mem));
+ if (!data->base) {
+ ret = -ENODEV;
+ dev_err(&pdev->dev, "Failed to ioremap memory\n");
+ goto err_mem_region;
+ }
+
+ ret = request_irq(data->irq, exynos4_tmu_irq,
+ IRQF_DISABLED | IRQF_TRIGGER_RISING,
+ "exynos4-tmu", data);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request irq: %d\n", data->irq);
+ goto err_io_remap;
+ }
+
+ data->clk = clk_get(NULL, "tmu_apbif");
+ if (IS_ERR(data->clk)) {
+ ret = PTR_ERR(data->clk);
+ dev_err(&pdev->dev, "Failed to get clock\n");
+ goto err_irq;
+ }
+
+ data->pdata = pdata;
+ platform_set_drvdata(pdev, data);
+ mutex_init(&data->lock);
+
+ ret = exynos4_tmu_initialize(pdev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to initialize TMU\n");
+ goto err_clk;
+ }
+
+ ret = sysfs_create_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to create sysfs group\n");
+ goto err_clk;
+ }
+
+ data->hwmon_dev = hwmon_device_register(&pdev->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ ret = PTR_ERR(data->hwmon_dev);
+ dev_err(&pdev->dev, "Failed to register hwmon device\n");
+ goto err_create_group;
+ }
+
+ exynos4_tmu_control(pdev, true);
+
+ return 0;
+
+err_create_group:
+ sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
+err_clk:
+ platform_set_drvdata(pdev, NULL);
+ clk_put(data->clk);
+err_irq:
+ free_irq(data->irq, data);
+err_io_remap:
+ iounmap(data->base);
+err_mem_region:
+ release_mem_region(data->mem->start, resource_size(data->mem));
+err_free:
+ kfree(data);
+
+ return ret;
+}
+
+static int __devexit exynos4_tmu_remove(struct platform_device *pdev)
+{
+ struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
+
+ exynos4_tmu_control(pdev, false);
+
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
+
+ clk_put(data->clk);
+
+ free_irq(data->irq, data);
+
+ iounmap(data->base);
+ release_mem_region(data->mem->start, resource_size(data->mem));
+
+ platform_set_drvdata(pdev, NULL);
+
+ kfree(data);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int exynos4_tmu_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ exynos4_tmu_control(pdev, false);
+
+ return 0;
+}
+
+static int exynos4_tmu_resume(struct platform_device *pdev)
+{
+ exynos4_tmu_initialize(pdev);
+ exynos4_tmu_control(pdev, true);
+
+ return 0;
+}
+#else
+#define exynos4_tmu_suspend NULL
+#define exynos4_tmu_resume NULL
+#endif
+
+static struct platform_driver exynos4_tmu_driver = {
+ .driver = {
+ .name = "exynos4-tmu",
+ .owner = THIS_MODULE,
+ },
+ .probe = exynos4_tmu_probe,
+ .remove = __devexit_p(exynos4_tmu_remove),
+ .suspend = exynos4_tmu_suspend,
+ .resume = exynos4_tmu_resume,
+};
+
+static int __init exynos4_tmu_driver_init(void)
+{
+ return platform_driver_register(&exynos4_tmu_driver);
+}
+module_init(exynos4_tmu_driver_init);
+
+static void __exit exynos4_tmu_driver_exit(void)
+{
+ platform_driver_unregister(&exynos4_tmu_driver);
+}
+module_exit(exynos4_tmu_driver_exit);
+
+MODULE_DESCRIPTION("EXYNOS4 TMU Driver");
+MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:exynos4-tmu");
diff --git a/include/linux/platform_data/exynos4_tmu.h b/include/linux/platform_data/exynos4_tmu.h
new file mode 100644
index 0000000..2534057
--- /dev/null
+++ b/include/linux/platform_data/exynos4_tmu.h
@@ -0,0 +1,83 @@
+/*
+ * exynos4_tmu.h - Samsung EXYNOS4 TMU (Thermal Management Unit)
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * Donggeun Kim <dg77.kim@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _LINUX_EXYNOS4_TMU_H
+#define _LINUX_EXYNOS4_TMU_H
+
+enum calibration_type {
+ TYPE_ONE_POINT_TRIMMING,
+ TYPE_TWO_POINT_TRIMMING,
+ TYPE_NONE,
+};
+
+/**
+ * struct exynos4_tmu_platform_data
+ * @threshold: basic temperature for generating interrupt
+ * [unit: degree Celsius]
+ * @trigger_levels: array for each interrupt levels
+ * [unit: degree Celsius]
+ * 0: temperature for trigger_level0 interrupt
+ * condition for trigger_level0 interrupt:
+ * current temperature > threshold + trigger_levels[0]
+ * 1: temperature for trigger_level1 interrupt
+ * condition for trigger_level1 interrupt:
+ * current temperature > threshold + trigger_levels[1]
+ * 2: temperature for trigger_level2 interrupt
+ * condition for trigger_level2 interrupt:
+ * current temperature > threshold + trigger_levels[2]
+ * 3: temperature for trigger_level3 interrupt
+ * condition for trigger_level3 interrupt:
+ * current temperature > threshold + trigger_levels[3]
+ * @trigger_level0_en:
+ * 1 = enable trigger_level0 interrupt,
+ * 0 = disable trigger_level0 interrupt
+ * @trigger_level1_en:
+ * 1 = enable trigger_level1 interrupt,
+ * 0 = disable trigger_level1 interrupt
+ * @trigger_level2_en:
+ * 1 = enable trigger_level2 interrupt,
+ * 0 = disable trigger_level2 interrupt
+ * @trigger_level3_en:
+ * 1 = enable trigger_level3 interrupt,
+ * 0 = disable trigger_level3 interrupt
+ * @gain: gain of amplifier in the positive-TC generator block
+ * 0 <= gain <= 15
+ * @reference_voltage: reference voltage of amplifier
+ * in the positive-TC generator block
+ * 0 <= reference_voltage <= 31
+ * @cal_type: calibration type for temperature
+ *
+ * This structure is required for configuration of exynos4_tmu driver.
+ */
+struct exynos4_tmu_platform_data {
+ u8 threshold;
+ u8 trigger_levels[4];
+ bool trigger_level0_en;
+ bool trigger_level1_en;
+ bool trigger_level2_en;
+ bool trigger_level3_en;
+
+ u8 gain;
+ u8 reference_voltage;
+
+ enum calibration_type cal_type;
+};
+#endif /* _LINUX_EXYNOS4_TMU_H */
--
1.7.4.1
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^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU
2011-08-31 8:56 [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU Donggeun Kim
@ 2011-09-01 5:22 ` Guenter Roeck
2011-09-01 8:17 ` Donggeun Kim
2011-09-01 15:59 ` Guenter Roeck
2 siblings, 0 replies; 4+ messages in thread
From: Guenter Roeck @ 2011-09-01 5:22 UTC (permalink / raw)
To: lm-sensors
On Wed, Aug 31, 2011 at 04:56:58AM -0400, Donggeun Kim wrote:
> Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
Couple of minor comments, plus a major one I overlooked earlier,
which will have to be discussed.
> Changes for v4
> - added comment for unit of threshold and trigger_levels
> - cleaned up code
> Changes for v3
> - cleaned up redundant code
> - added mutex
> - changed error codes
> Changes for v2
> - added six attributes for alarms
> - changed error code of EAGAIN
> - changed initialize function to return error code
>
> Documentation/hwmon/exynos4_tmu | 81 +++++
> drivers/hwmon/Kconfig | 10 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/exynos4_tmu.c | 533 +++++++++++++++++++++++++++++
> include/linux/platform_data/exynos4_tmu.h | 83 +++++
> 5 files changed, 708 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/hwmon/exynos4_tmu
> create mode 100644 drivers/hwmon/exynos4_tmu.c
> create mode 100644 include/linux/platform_data/exynos4_tmu.h
>
> diff --git a/Documentation/hwmon/exynos4_tmu b/Documentation/hwmon/exynos4_tmu
> new file mode 100644
> index 0000000..7fe12c1
> --- /dev/null
> +++ b/Documentation/hwmon/exynos4_tmu
> @@ -0,0 +1,81 @@
> +Kernel driver exynos4_tmu
> +========> +
> +Supported chips:
> +* ARM SAMSUNG EXYNOS4 series of SoC
> + Prefix: 'exynos4-tmu'
> + Datasheet: Not publicly available
> +
> +Authors: Donggeun Kim <dg77.kim@samsung.com>
> +
> +Description
> +-----------
> +
> +This driver allows to read temperature inside SAMSUNG EXYNOS4 series of SoC.
> +
> +The chip only exposes the measured 8-bit temperature code value
> +through a register.
> +Temperature can be taken from the temperature code.
> +There are three equations converting from temperature to temperature code.
> +
> +The three equations are:
> + 1. Two point trimming
> + Tc = (T - 25) * (TI2 - TI1) / (85 - 25) + TI1
> +
> + 2. One point trimming
> + Tc = T + TI1 - 25
> +
> + 3. No trimming
> + Tc = T + 50
> +
> + Tc: Temperature code, T: Temperature,
> + TI1: Trimming info for 25 degree Celsius (stored at TRIMINFO register)
> + Temperature code measured at 25 degree Celsius which is unchanged
> + TI2: Trimming info for 85 degree Celsius (stored at TRIMINFO register)
> + Temperature code measured at 85 degree Celsius which is unchanged
> +
> +TMU(Thermal Management Unit) in EXYNOS4 generates interrupt
> +when temperature exceeds pre-defined levels.
> +The maximum number of configurable threshold is four.
> +The threshold levels are defined as follows:
> + Level_0: current temperature > trigger_level_0 + threshold
> + Level_1: current temperature > trigger_level_1 + threshold
> + Level_2: current temperature > trigger_level_2 + threshold
> + Level_3: current temperature > trigger_level_3 + threshold
> +
> + The threshold and each trigger_level are set
> + through the corresponding registers.
> +
> +When an interrupt occurs, this driver notify user space of
> +one of four threshold levels for the interrupt
> +through kobject_uevent_env and sysfs_notify functions.
> +Although an interrupt condition for level_0 can be set,
> +it is not notified to user space through sysfs_notify function.
> +
> +Sysfs Interface
> +---------------
> +name name of the temperature sensor
> + RO
> +
> +temp1_input temperature
> + RO
> +
> +temp1_max temperature for level_1 interrupt
> + RO
> +
> +temp1_crit temperature for level_2 interrupt
> + RO
> +
> +temp1_emergency temperature for level_3 interrupt
> + RO
> +
> +temp1_max_alarm alarm for level_1 interrupt
> + RO
> +
> +temp1_crit_alarm
> + alarm for level_2 interrupt
> + RO
> +
> +temp1_emergency_alarm
> + alarm for level_3 interrupt
> + RO
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 0b62c3c..c6fb761 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -303,6 +303,16 @@ config SENSORS_DS1621
> This driver can also be built as a module. If so, the module
> will be called ds1621.
>
> +config SENSORS_EXYNOS4_TMU
> + tristate "Temperature sensor on Samsung EXYNOS4"
> + depends on EXYNOS4_DEV_TMU
> + help
> + If you say yes here you get support for TMU (Thermal Managment
> + Unit) on SAMSUNG EXYNOS4 series of SoC.
> +
> + This driver can also be built as a module. If so, the module
> + will be called exynos4-tmu.
> +
> config SENSORS_I5K_AMB
> tristate "FB-DIMM AMB temperature sensor on Intel 5000 series chipsets"
> depends on PCI && EXPERIMENTAL
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 3c9ccef..dbd8963 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -47,6 +47,7 @@ obj-$(CONFIG_SENSORS_DS1621) += ds1621.o
> obj-$(CONFIG_SENSORS_EMC1403) += emc1403.o
> obj-$(CONFIG_SENSORS_EMC2103) += emc2103.o
> obj-$(CONFIG_SENSORS_EMC6W201) += emc6w201.o
> +obj-$(CONFIG_SENSORS_EXYNOS4_TMU) += exynos4_tmu.o
> obj-$(CONFIG_SENSORS_F71805F) += f71805f.o
> obj-$(CONFIG_SENSORS_F71882FG) += f71882fg.o
> obj-$(CONFIG_SENSORS_F75375S) += f75375s.o
> diff --git a/drivers/hwmon/exynos4_tmu.c b/drivers/hwmon/exynos4_tmu.c
> new file mode 100644
> index 0000000..9d1002a
> --- /dev/null
> +++ b/drivers/hwmon/exynos4_tmu.c
> @@ -0,0 +1,533 @@
> +/*
> + * exynos4_tmu.c - Samsung EXYNOS4 TMU (Thermal Management Unit)
> + *
> + * Copyright (C) 2011 Samsung Electronics
> + * Donggeun Kim <dg77.kim@samsung.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/err.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/platform_device.h>
> +#include <linux/interrupt.h>
> +#include <linux/clk.h>
> +#include <linux/workqueue.h>
> +#include <linux/sysfs.h>
> +#include <linux/kobject.h>
> +#include <linux/io.h>
> +#include <linux/mutex.h>
> +
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +
> +#include <linux/platform_data/exynos4_tmu.h>
> +
> +#define EXYNOS4_TMU_REG_TRIMINFO 0x0
> +#define EXYNOS4_TMU_REG_CONTROL 0x20
> +#define EXYNOS4_TMU_REG_STATUS 0x28
> +#define EXYNOS4_TMU_REG_CURRENT_TEMP 0x40
> +#define EXYNOS4_TMU_REG_THRESHOLD_TEMP 0x44
> +#define EXYNOS4_TMU_REG_TRIG_LEVEL0 0x50
> +#define EXYNOS4_TMU_REG_TRIG_LEVEL1 0x54
> +#define EXYNOS4_TMU_REG_TRIG_LEVEL2 0x58
> +#define EXYNOS4_TMU_REG_TRIG_LEVEL3 0x5C
> +#define EXYNOS4_TMU_REG_PAST_TEMP0 0x60
> +#define EXYNOS4_TMU_REG_PAST_TEMP1 0x64
> +#define EXYNOS4_TMU_REG_PAST_TEMP2 0x68
> +#define EXYNOS4_TMU_REG_PAST_TEMP3 0x6C
> +#define EXYNOS4_TMU_REG_INTEN 0x70
> +#define EXYNOS4_TMU_REG_INTSTAT 0x74
> +#define EXYNOS4_TMU_REG_INTCLEAR 0x78
> +
> +#define EXYNOS4_TMU_GAIN_SHIFT 8
> +#define EXYNOS4_TMU_REF_VOLTAGE_SHIFT 24
> +
> +#define EXYNOS4_TMU_TRIM_TEMP_MASK 0xff
> +#define EXYNOS4_TMU_CORE_ON 3
> +#define EXYNOS4_TMU_CORE_OFF 2
> +#define EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET 50
> +#define EXYNOS4_TMU_TRIG_LEVEL0_MASK 0x1
> +#define EXYNOS4_TMU_TRIG_LEVEL1_MASK 0x10
> +#define EXYNOS4_TMU_TRIG_LEVEL2_MASK 0x100
> +#define EXYNOS4_TMU_TRIG_LEVEL3_MASK 0x1000
> +#define EXYNOS4_TMU_INTCLEAR_VAL 0x1111
> +
> +struct exynos4_tmu_data {
> + struct exynos4_tmu_platform_data *pdata;
> + struct device *hwmon_dev;
> + struct resource *mem;
> + void __iomem *base;
> + int irq;
> + struct work_struct irq_work;
> + struct mutex lock;
> + struct clk *clk;
> + unsigned int interrupt_stat;
> + u8 temp_error1, temp_error2;
> +};
> +
> +/*
> + * TMU treats temperature as a mapped temperature code.
> + * The temperature is converted differently depending on the calibration type.
> + */
> +static u8 translate_temp_to_code(struct exynos4_tmu_data *data, u8 temp)
> +{
You don't really need "translate_" here.
> + struct exynos4_tmu_platform_data *pdata = data->pdata;
> + unsigned int temp_code;
> +
> + switch (pdata->cal_type) {
> + case TYPE_TWO_POINT_TRIMMING:
> + temp_code = (temp - 25) *
> + (data->temp_error2 - data->temp_error1) /
> + (85 - 25) + data->temp_error1;
> + break;
> + case TYPE_ONE_POINT_TRIMMING:
> + temp_code = temp + data->temp_error1 - 25;
> + break;
> + default:
> + temp_code = temp + EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
> + break;
> + }
A bit of an overall question/concern - with all those calculations, can there
be over- or underflows ? What if temp_code is < 0 (ie 0xffffffXX) or > 255 ?
> +
> + return temp_code;
> +}
> +
> +/*
> + * Calculate a temperature value from a temperature code.
> + * The unit of the temperature is degree Celsius.
> + */
> +static u8 translate_code_to_temp(struct exynos4_tmu_data *data, u8 temp_code)
> +{
Same commant as above.
> + struct exynos4_tmu_platform_data *pdata = data->pdata;
> + unsigned int temp;
> +
> + switch (pdata->cal_type) {
> + case TYPE_TWO_POINT_TRIMMING:
> + temp = (temp_code - data->temp_error1) * (85 - 25) /
> + (data->temp_error2 - data->temp_error1) + 25;
> + break;
> + case TYPE_ONE_POINT_TRIMMING:
> + temp = temp_code - data->temp_error1 + 25;
> + break;
> + default:
> + temp = temp_code - EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
> + break;
> + }
> +
Any over- or underflow concerns here ?
> + return temp;
> +}
> +
> +static int exynos4_tmu_initialize(struct platform_device *pdev)
> +{
> + struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
> + struct exynos4_tmu_platform_data *pdata = data->pdata;
> + unsigned int status, trim_info;
> + u8 threshold_code;
> +
> + mutex_lock(&data->lock);
> + clk_enable(data->clk);
> +
> + status = readb(data->base + EXYNOS4_TMU_REG_STATUS);
> + if (!status) {
> + clk_disable(data->clk);
> + mutex_unlock(&data->lock);
> + return -EBUSY;
> + }
Coding style says you should use common return handling here.
Is this really EBUSY ?
> +
> + /* Save trimming info in order to perform calibration */
> + trim_info = readl(data->base + EXYNOS4_TMU_REG_TRIMINFO);
> + data->temp_error1 = trim_info & EXYNOS4_TMU_TRIM_TEMP_MASK;
> + data->temp_error2 = ((trim_info >> 8) & EXYNOS4_TMU_TRIM_TEMP_MASK);
> +
> + /* Write temperature code for threshold */
> + threshold_code = translate_temp_to_code(data, pdata->threshold);
> + writeb(threshold_code,
> + data->base + EXYNOS4_TMU_REG_THRESHOLD_TEMP);
> +
> + writeb(pdata->trigger_levels[0],
> + data->base + EXYNOS4_TMU_REG_TRIG_LEVEL0);
> + writeb(pdata->trigger_levels[1],
> + data->base + EXYNOS4_TMU_REG_TRIG_LEVEL1);
> + writeb(pdata->trigger_levels[2],
> + data->base + EXYNOS4_TMU_REG_TRIG_LEVEL2);
> + writeb(pdata->trigger_levels[3],
> + data->base + EXYNOS4_TMU_REG_TRIG_LEVEL3);
> +
> + writel(EXYNOS4_TMU_INTCLEAR_VAL,
> + data->base + EXYNOS4_TMU_REG_INTCLEAR);
> +
> + clk_disable(data->clk);
> + mutex_unlock(&data->lock);
> +
> + return 0;
> +}
> +
> +static void exynos4_tmu_control(struct platform_device *pdev, bool on)
> +{
> + struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
> + struct exynos4_tmu_platform_data *pdata = data->pdata;
> + unsigned int con, interrupt_en;
> +
> + mutex_lock(&data->lock);
> + clk_enable(data->clk);
> +
> + interrupt_en = pdata->trigger_level3_en << 12 |
> + pdata->trigger_level2_en << 8 |
> + pdata->trigger_level1_en << 4 |
> + pdata->trigger_level0_en;
> +
> + con = pdata->reference_voltage << EXYNOS4_TMU_REF_VOLTAGE_SHIFT |
> + pdata->gain << EXYNOS4_TMU_GAIN_SHIFT;
> + if (on)
> + con |= EXYNOS4_TMU_CORE_ON;
Move interrupt_en assignment from above to here.
> + else {
> + con |= EXYNOS4_TMU_CORE_OFF;
> + interrupt_en = 0; /* Disable all interrupts */
> + }
> + writel(interrupt_en, data->base + EXYNOS4_TMU_REG_INTEN);
> + writel(con, data->base + EXYNOS4_TMU_REG_CONTROL);
> +
> + clk_disable(data->clk);
> + mutex_unlock(&data->lock);
> +}
> +
> +static int exynos4_tmu_read(struct exynos4_tmu_data *data)
> +{
> + u8 temp_code, temp;
> +
> + mutex_lock(&data->lock);
> + clk_enable(data->clk);
> +
> + temp_code = readb(data->base + EXYNOS4_TMU_REG_CURRENT_TEMP);
> + if (!temp_code) {
> + clk_disable(data->clk);
> + mutex_unlock(&data->lock);
> + return -ENODATA;
> + }
Should use common return handling. See CodingStyle, Chapter 7.
> + temp = translate_code_to_temp(data, temp_code);
> +
> + clk_disable(data->clk);
> + mutex_unlock(&data->lock);
> +
> + return temp;
> +}
> +
> +static void exynos4_tmu_work(struct work_struct *work)
> +{
> + struct exynos4_tmu_data *data = container_of(work,
> + struct exynos4_tmu_data, irq_work);
> + char *envp[2];
> +
> + mutex_lock(&data->lock);
> + clk_enable(data->clk);
> +
> + data->interrupt_stat = readl(data->base + EXYNOS4_TMU_REG_INTSTAT);
> +
> + writel(EXYNOS4_TMU_INTCLEAR_VAL, data->base + EXYNOS4_TMU_REG_INTCLEAR);
> +
> + if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL3_MASK) {
> + envp[0] = "TRIG_LEVEL=3";
> + sysfs_notify(&data->hwmon_dev->kobj, NULL,
> + "temp1_emergency_alarm");
> + } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL2_MASK) {
> + envp[0] = "TRIG_LEVEL=2";
> + sysfs_notify(&data->hwmon_dev->kobj, NULL,
> + "temp1_crit_alarm");
> + } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL1_MASK) {
> + envp[0] = "TRIG_LEVEL=1";
> + sysfs_notify(&data->hwmon_dev->kobj, NULL, "temp1_max_alarm");
> + } else
> + envp[0] = "TRIG_LEVEL=0";
> + envp[1] = NULL;
> +
> + kobject_uevent_env(&data->hwmon_dev->kobj, KOBJ_CHANGE, envp);
> +
This is the big one. We'll have to decide how to handle this. There is currently
no ABI for uevents. If we permit uevents, I think there should be a common ABI,
and we should avoid a situation where every driver returns a different set of events.
> + enable_irq(data->irq);
> +
> + clk_disable(data->clk);
> + mutex_unlock(&data->lock);
> +}
> +
> +static irqreturn_t exynos4_tmu_irq(int irq, void *id)
> +{
> + struct exynos4_tmu_data *data = id;
> +
> + disable_irq_nosync(irq);
> + schedule_work(&data->irq_work);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static ssize_t exynos4_tmu_show_name(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sprintf(buf, "exynos4-tmu\n");
> +}
> +
> +static ssize_t exynos4_tmu_show_temp(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct exynos4_tmu_data *data = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = exynos4_tmu_read(data);
> + if (ret < 0)
> + return ret;
> +
> + /* convert from degree Celsius to millidegree Celsius */
> + return sprintf(buf, "%d\n", ret * 1000);
> +}
> +
> +static ssize_t exynos4_tmu_show_alarm(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> + struct exynos4_tmu_data *data = dev_get_drvdata(dev);
> + struct exynos4_tmu_platform_data *pdata = data->pdata;
> + int temp;
> + unsigned int trigger_level;
> +
> + temp = exynos4_tmu_read(data);
> + if (temp < 0)
> + return temp;
> +
> + trigger_level = pdata->threshold + pdata->trigger_levels[attr->index];
> +
> + return sprintf(buf, "%d\n", temp > trigger_level ? 1 : 0);
return sprintf(buf, "%d\n", !!(temp > trigger_level));
is a bit simpler and avoids a branch.
> +}
> +
> +static ssize_t exynos4_tmu_show_level(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> + struct exynos4_tmu_data *data = dev_get_drvdata(dev);
> + struct exynos4_tmu_platform_data *pdata = data->pdata;
> + unsigned int temp = pdata->threshold +
> + pdata->trigger_levels[attr->index];
> +
> + return sprintf(buf, "%d\n", temp * 1000);
Nitpick - temp is unsigned here, so %u would be more apropriate.
> +}
> +
> +static DEVICE_ATTR(name, S_IRUGO, exynos4_tmu_show_name, NULL);
> +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, exynos4_tmu_show_temp, NULL, 0);
> +
> +static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO,
> + exynos4_tmu_show_alarm, NULL, 1);
> +static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO,
> + exynos4_tmu_show_alarm, NULL, 2);
> +static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO,
> + exynos4_tmu_show_alarm, NULL, 3);
> +
> +static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, exynos4_tmu_show_level, NULL, 1);
> +static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, exynos4_tmu_show_level, NULL, 2);
> +static SENSOR_DEVICE_ATTR(temp1_emergency, S_IRUGO,
> + exynos4_tmu_show_level, NULL, 3);
> +
> +static struct attribute *exynos4_tmu_attributes[] = {
> + &dev_attr_name.attr,
> + &sensor_dev_attr_temp1_input.dev_attr.attr,
> + &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
> + &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
> + &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr,
> + &sensor_dev_attr_temp1_max.dev_attr.attr,
> + &sensor_dev_attr_temp1_crit.dev_attr.attr,
> + &sensor_dev_attr_temp1_emergency.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group exynos4_tmu_attr_group = {
> + .attrs = exynos4_tmu_attributes,
> +};
> +
> +static int __devinit exynos4_tmu_probe(struct platform_device *pdev)
> +{
> + struct exynos4_tmu_data *data;
> + struct exynos4_tmu_platform_data *pdata = pdev->dev.platform_data;
> + int ret;
> +
> + if (!pdata) {
> + dev_err(&pdev->dev, "No platform init data supplied.\n");
> + return -ENODEV;
> + }
> +
> + data = kzalloc(sizeof(struct exynos4_tmu_data), GFP_KERNEL);
> + if (!data) {
> + dev_err(&pdev->dev, "Failed to allocate driver structure\n");
> + return -ENOMEM;
> + }
> +
> + data->irq = platform_get_irq(pdev, 0);
> + if (data->irq < 0) {
> + ret = data->irq;
> + dev_err(&pdev->dev, "Failed to get platform irq\n");
> + goto err_free;
> + }
> +
> + INIT_WORK(&data->irq_work, exynos4_tmu_work);
> +
> + data->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!data->mem) {
> + ret = -ENOENT;
> + dev_err(&pdev->dev, "Failed to get platform resource\n");
> + goto err_free;
> + }
> +
> + data->mem = request_mem_region(data->mem->start,
> + resource_size(data->mem), pdev->name);
> + if (!data->mem) {
> + ret = -ENODEV;
> + dev_err(&pdev->dev, "Failed to request memory region\n");
> + goto err_free;
> + }
> +
> + data->base = ioremap(data->mem->start, resource_size(data->mem));
> + if (!data->base) {
> + ret = -ENODEV;
> + dev_err(&pdev->dev, "Failed to ioremap memory\n");
> + goto err_mem_region;
> + }
> +
> + ret = request_irq(data->irq, exynos4_tmu_irq,
> + IRQF_DISABLED | IRQF_TRIGGER_RISING,
> + "exynos4-tmu", data);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to request irq: %d\n", data->irq);
> + goto err_io_remap;
> + }
> +
> + data->clk = clk_get(NULL, "tmu_apbif");
> + if (IS_ERR(data->clk)) {
> + ret = PTR_ERR(data->clk);
> + dev_err(&pdev->dev, "Failed to get clock\n");
> + goto err_irq;
> + }
> +
> + data->pdata = pdata;
> + platform_set_drvdata(pdev, data);
> + mutex_init(&data->lock);
> +
> + ret = exynos4_tmu_initialize(pdev);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to initialize TMU\n");
> + goto err_clk;
> + }
> +
> + ret = sysfs_create_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to create sysfs group\n");
> + goto err_clk;
> + }
> +
> + data->hwmon_dev = hwmon_device_register(&pdev->dev);
> + if (IS_ERR(data->hwmon_dev)) {
> + ret = PTR_ERR(data->hwmon_dev);
> + dev_err(&pdev->dev, "Failed to register hwmon device\n");
> + goto err_create_group;
> + }
> +
> + exynos4_tmu_control(pdev, true);
> +
> + return 0;
> +
> +err_create_group:
> + sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
> +err_clk:
> + platform_set_drvdata(pdev, NULL);
> + clk_put(data->clk);
> +err_irq:
> + free_irq(data->irq, data);
> +err_io_remap:
> + iounmap(data->base);
> +err_mem_region:
> + release_mem_region(data->mem->start, resource_size(data->mem));
> +err_free:
> + kfree(data);
> +
> + return ret;
> +}
> +
> +static int __devexit exynos4_tmu_remove(struct platform_device *pdev)
> +{
> + struct exynos4_tmu_data *data = platform_get_drvdata(pdev);
> +
> + exynos4_tmu_control(pdev, false);
> +
> + hwmon_device_unregister(data->hwmon_dev);
> + sysfs_remove_group(&pdev->dev.kobj, &exynos4_tmu_attr_group);
> +
> + clk_put(data->clk);
> +
> + free_irq(data->irq, data);
> +
> + iounmap(data->base);
> + release_mem_region(data->mem->start, resource_size(data->mem));
> +
> + platform_set_drvdata(pdev, NULL);
> +
> + kfree(data);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int exynos4_tmu_suspend(struct platform_device *pdev, pm_message_t state)
> +{
> + exynos4_tmu_control(pdev, false);
> +
> + return 0;
> +}
> +
> +static int exynos4_tmu_resume(struct platform_device *pdev)
> +{
> + exynos4_tmu_initialize(pdev);
> + exynos4_tmu_control(pdev, true);
> +
> + return 0;
> +}
> +#else
> +#define exynos4_tmu_suspend NULL
> +#define exynos4_tmu_resume NULL
> +#endif
> +
> +static struct platform_driver exynos4_tmu_driver = {
> + .driver = {
> + .name = "exynos4-tmu",
> + .owner = THIS_MODULE,
> + },
> + .probe = exynos4_tmu_probe,
> + .remove = __devexit_p(exynos4_tmu_remove),
> + .suspend = exynos4_tmu_suspend,
> + .resume = exynos4_tmu_resume,
> +};
> +
> +static int __init exynos4_tmu_driver_init(void)
> +{
> + return platform_driver_register(&exynos4_tmu_driver);
> +}
> +module_init(exynos4_tmu_driver_init);
> +
> +static void __exit exynos4_tmu_driver_exit(void)
> +{
> + platform_driver_unregister(&exynos4_tmu_driver);
> +}
> +module_exit(exynos4_tmu_driver_exit);
> +
> +MODULE_DESCRIPTION("EXYNOS4 TMU Driver");
> +MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:exynos4-tmu");
> diff --git a/include/linux/platform_data/exynos4_tmu.h b/include/linux/platform_data/exynos4_tmu.h
> new file mode 100644
> index 0000000..2534057
> --- /dev/null
> +++ b/include/linux/platform_data/exynos4_tmu.h
> @@ -0,0 +1,83 @@
> +/*
> + * exynos4_tmu.h - Samsung EXYNOS4 TMU (Thermal Management Unit)
> + *
> + * Copyright (C) 2011 Samsung Electronics
> + * Donggeun Kim <dg77.kim@samsung.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + */
> +
> +#ifndef _LINUX_EXYNOS4_TMU_H
> +#define _LINUX_EXYNOS4_TMU_H
> +
> +enum calibration_type {
> + TYPE_ONE_POINT_TRIMMING,
> + TYPE_TWO_POINT_TRIMMING,
> + TYPE_NONE,
> +};
> +
> +/**
> + * struct exynos4_tmu_platform_data
> + * @threshold: basic temperature for generating interrupt
> + * [unit: degree Celsius]
> + * @trigger_levels: array for each interrupt levels
> + * [unit: degree Celsius]
> + * 0: temperature for trigger_level0 interrupt
> + * condition for trigger_level0 interrupt:
> + * current temperature > threshold + trigger_levels[0]
> + * 1: temperature for trigger_level1 interrupt
> + * condition for trigger_level1 interrupt:
> + * current temperature > threshold + trigger_levels[1]
> + * 2: temperature for trigger_level2 interrupt
> + * condition for trigger_level2 interrupt:
> + * current temperature > threshold + trigger_levels[2]
> + * 3: temperature for trigger_level3 interrupt
> + * condition for trigger_level3 interrupt:
> + * current temperature > threshold + trigger_levels[3]
> + * @trigger_level0_en:
> + * 1 = enable trigger_level0 interrupt,
> + * 0 = disable trigger_level0 interrupt
> + * @trigger_level1_en:
> + * 1 = enable trigger_level1 interrupt,
> + * 0 = disable trigger_level1 interrupt
> + * @trigger_level2_en:
> + * 1 = enable trigger_level2 interrupt,
> + * 0 = disable trigger_level2 interrupt
> + * @trigger_level3_en:
> + * 1 = enable trigger_level3 interrupt,
> + * 0 = disable trigger_level3 interrupt
> + * @gain: gain of amplifier in the positive-TC generator block
> + * 0 <= gain <= 15
> + * @reference_voltage: reference voltage of amplifier
> + * in the positive-TC generator block
> + * 0 <= reference_voltage <= 31
> + * @cal_type: calibration type for temperature
> + *
> + * This structure is required for configuration of exynos4_tmu driver.
> + */
> +struct exynos4_tmu_platform_data {
> + u8 threshold;
> + u8 trigger_levels[4];
> + bool trigger_level0_en;
> + bool trigger_level1_en;
> + bool trigger_level2_en;
> + bool trigger_level3_en;
> +
> + u8 gain;
> + u8 reference_voltage;
> +
> + enum calibration_type cal_type;
> +};
> +#endif /* _LINUX_EXYNOS4_TMU_H */
> --
> 1.7.4.1
>
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU
2011-08-31 8:56 [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU Donggeun Kim
2011-09-01 5:22 ` Guenter Roeck
@ 2011-09-01 8:17 ` Donggeun Kim
2011-09-01 15:59 ` Guenter Roeck
2 siblings, 0 replies; 4+ messages in thread
From: Donggeun Kim @ 2011-09-01 8:17 UTC (permalink / raw)
To: lm-sensors
On 2011년 09월 01일 14:22, Guenter Roeck wrote:
> On Wed, Aug 31, 2011 at 04:56:58AM -0400, Donggeun Kim wrote:
>> Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
>> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
>> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
>> ---
[snip]
>> + struct exynos4_tmu_platform_data *pdata = data->pdata;
>> + unsigned int temp_code;
>> +
>> + switch (pdata->cal_type) {
>> + case TYPE_TWO_POINT_TRIMMING:
>> + temp_code = (temp - 25) *
>> + (data->temp_error2 - data->temp_error1) /
>> + (85 - 25) + data->temp_error1;
>> + break;
>> + case TYPE_ONE_POINT_TRIMMING:
>> + temp_code = temp + data->temp_error1 - 25;
>> + break;
>> + default:
>> + temp_code = temp + EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
>> + break;
>> + }
>
> A bit of an overall question/concern - with all those calculations, can there
> be over- or underflows ? What if temp_code is < 0 (ie 0xffffffXX) or > 255 ?
>
temp should range between 25 and 125. So, the argument should be checked
whether it is over or under the range.
I will fix it.
[snip]
>> + struct exynos4_tmu_platform_data *pdata = data->pdata;
>> + unsigned int temp;
>> +
>> + switch (pdata->cal_type) {
>> + case TYPE_TWO_POINT_TRIMMING:
>> + temp = (temp_code - data->temp_error1) * (85 - 25) /
>> + (data->temp_error2 - data->temp_error1) + 25;
>> + break;
>> + case TYPE_ONE_POINT_TRIMMING:
>> + temp = temp_code - data->temp_error1 + 25;
>> + break;
>> + default:
>> + temp = temp_code - EXYNOS4_TMU_DEF_CODE_TO_TEMP_OFFSET;
>> + break;
>> + }
>> +
> Any over- or underflow concerns here ?
>
temp_code, which is read from register, should range between 75 and 175.
It also should be checked.
[snip]
>> +static void exynos4_tmu_work(struct work_struct *work)
>> +{
>> + struct exynos4_tmu_data *data = container_of(work,
>> + struct exynos4_tmu_data, irq_work);
>> + char *envp[2];
>> +
>> + mutex_lock(&data->lock);
>> + clk_enable(data->clk);
>> +
>> + data->interrupt_stat = readl(data->base + EXYNOS4_TMU_REG_INTSTAT);
>> +
>> + writel(EXYNOS4_TMU_INTCLEAR_VAL, data->base + EXYNOS4_TMU_REG_INTCLEAR);
>> +
>> + if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL3_MASK) {
>> + envp[0] = "TRIG_LEVEL=3";
>> + sysfs_notify(&data->hwmon_dev->kobj, NULL,
>> + "temp1_emergency_alarm");
>> + } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL2_MASK) {
>> + envp[0] = "TRIG_LEVEL=2";
>> + sysfs_notify(&data->hwmon_dev->kobj, NULL,
>> + "temp1_crit_alarm");
>> + } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL1_MASK) {
>> + envp[0] = "TRIG_LEVEL=1";
>> + sysfs_notify(&data->hwmon_dev->kobj, NULL, "temp1_max_alarm");
>> + } else
>> + envp[0] = "TRIG_LEVEL=0";
>> + envp[1] = NULL;
>> +
>> + kobject_uevent_env(&data->hwmon_dev->kobj, KOBJ_CHANGE, envp);
>> +
> This is the big one. We'll have to decide how to handle this. There is currently
> no ABI for uevents. If we permit uevents, I think there should be a common ABI,
> and we should avoid a situation where every driver returns a different set of events.
>
If you have the common ABI for uevents in mind, I will follow it.
If calling 'kobject_uevent_env' is the matter, I consider replacing it
with koject_uevent function.
Thanks.
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU
2011-08-31 8:56 [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU Donggeun Kim
2011-09-01 5:22 ` Guenter Roeck
2011-09-01 8:17 ` Donggeun Kim
@ 2011-09-01 15:59 ` Guenter Roeck
2 siblings, 0 replies; 4+ messages in thread
From: Guenter Roeck @ 2011-09-01 15:59 UTC (permalink / raw)
To: lm-sensors
On Thu, 2011-09-01 at 04:17 -0400, Donggeun Kim wrote:
> On 2011년 09월 01일 14:22, Guenter Roeck wrote:
> > On Wed, Aug 31, 2011 at 04:56:58AM -0400, Donggeun Kim wrote:
> >> Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
> >> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
> >> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
> >> ---
> [snip]
[ ... ]
> >> + if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL3_MASK) {
> >> + envp[0] = "TRIG_LEVEL=3";
> >> + sysfs_notify(&data->hwmon_dev->kobj, NULL,
> >> + "temp1_emergency_alarm");
> >> + } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL2_MASK) {
> >> + envp[0] = "TRIG_LEVEL=2";
> >> + sysfs_notify(&data->hwmon_dev->kobj, NULL,
> >> + "temp1_crit_alarm");
> >> + } else if (data->interrupt_stat & EXYNOS4_TMU_TRIG_LEVEL1_MASK) {
> >> + envp[0] = "TRIG_LEVEL=1";
> >> + sysfs_notify(&data->hwmon_dev->kobj, NULL, "temp1_max_alarm");
> >> + } else
> >> + envp[0] = "TRIG_LEVEL=0";
> >> + envp[1] = NULL;
> >> +
> >> + kobject_uevent_env(&data->hwmon_dev->kobj, KOBJ_CHANGE, envp);
> >> +
> > This is the big one. We'll have to decide how to handle this. There is currently
> > no ABI for uevents. If we permit uevents, I think there should be a common ABI,
> > and we should avoid a situation where every driver returns a different set of events.
> >
> If you have the common ABI for uevents in mind, I will follow it.
> If calling 'kobject_uevent_env' is the matter, I consider replacing it
> with koject_uevent function.
>
Problem is that we do not (yet) have such a common ABI for hwmon
drivers.
Yes, I am specifically concerned about the env data - not that I am
opposed to provide such data in general, but it should not be device
specific. Anything device specific will cause a mess going forward, if
and when other drivers introduce other device specific events.
Jean, any input on this discussion ?
Thanks,
Guenter
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^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2011-09-01 15:59 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2011-08-31 8:56 [lm-sensors] [PATCH v4] hwmon: Add driver for EXYNOS4 TMU Donggeun Kim
2011-09-01 5:22 ` Guenter Roeck
2011-09-01 8:17 ` Donggeun Kim
2011-09-01 15:59 ` Guenter Roeck
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