[PATCH v3] hwmon: Driver for TI TMP103 temperature sensor

[PATCH v3] hwmon: Driver for TI TMP103 temperature sensor

[Heiko Schocher]

Driver for the TI TMP103.

The TI TMP103 is similar to the TMP102.  It differs from the TMP102
by having only 8 bit registers.

Signed-off-by: Heiko Schocher <hs@denx.de>

---

Cc: Jean Delvare <khali@linux-fr.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-doc@vger.kernel.org

- change for v2:
  - add comments from GuenterRoeck:
    - remove Cc from commit subject
    - add devicetree maintainer
    - move Documentation to Documentation/hwmon/tmp103
    - remove devicetree bindings from Documentation
    - add compatible string to
      "Documentation/devicetree/bindings/i2c/trivial-devices.txt"
    - remove CamelCase
    - fix Codingstyle issues
    - use ATTRIBUTE_GROUPS and devm_hwmon_device_register_with_groups()
    - remove unsused define TMP103_CONFIG_RD_ONLY
    - restore config register when exit()
    - use regmap
- changes for v3:
  again a lot of fantastic tips how to use regmap efficiently
  from Guenter Roeck:
  - get rid of "struct tmp103"
  - get rid of "static const u8 tmp103_reg[]"
  - get rid of mutex lock
  - drop config_orig entirely
  - use regmap_update_bits()

 .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
 Documentation/hwmon/tmp103                         |  28 +++
 drivers/hwmon/Kconfig                              |  10 +
 drivers/hwmon/Makefile                             |   1 +
 drivers/hwmon/tmp103.c                             | 203 +++++++++++++++++++++
 5 files changed, 243 insertions(+)
 create mode 100644 Documentation/hwmon/tmp103
 create mode 100644 drivers/hwmon/tmp103.c

diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index bef86e5..fc944e0 100644
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -83,5 +83,6 @@ stm,m41t80		M41T80 - SERIAL ACCESS RTC WITH ALARMS
 taos,tsl2550		Ambient Light Sensor with SMBUS/Two Wire Serial Interface
 ti,tsc2003		I2C Touch-Screen Controller
 ti,tmp102		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
+ti,tmp103		Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface
 ti,tmp275		Digital Temperature Sensor
 winbond,wpct301		i2c trusted platform module (TPM)
diff --git a/Documentation/hwmon/tmp103 b/Documentation/hwmon/tmp103
new file mode 100644
index 0000000..ec00a15
--- /dev/null
+++ b/Documentation/hwmon/tmp103
@@ -0,0 +1,28 @@
+Kernel driver tmp103
+====================
+
+Supported chips:
+  * Texas Instruments TMP103
+    Prefix: 'tmp103'
+    Addresses scanned: none
+    Product info and datasheet: http://www.ti.com/product/tmp103
+
+Author:
+	Heiko Schocher <hs@denx.de>
+
+Description
+-----------
+
+The TMP103 is a digital output temperature sensor in a four-ball
+wafer chip-scale package (WCSP). The TMP103 is capable of reading
+temperatures to a resolution of 1°C. The TMP103 is specified for
+operation over a temperature range of –40°C to +125°C.
+
+Resolution: 8 Bits
+Accuracy: ±1°C Typ (–10°C to +100°C)
+
+The driver provides the common sysfs-interface for temperatures (see
+Documentation/hwmon/sysfs-interface under Temperatures).
+
+Please refer how to instantiate this driver:
+Documentation/i2c/instantiating-devices
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 08531a1..c882d4b 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1391,6 +1391,16 @@ config SENSORS_TMP102
 	  This driver can also be built as a module.  If so, the module
 	  will be called tmp102.
 
+config SENSORS_TMP103
+	tristate "Texas Instruments TMP103"
+	depends on I2C
+	help
+	  If you say yes here you get support for Texas Instruments TMP103
+	  sensor chips.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called tmp103.
+
 config SENSORS_TMP401
 	tristate "Texas Instruments TMP401 and compatibles"
 	depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 3dc0f02..cc0df1ef 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -135,6 +135,7 @@ obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
 obj-$(CONFIG_SENSORS_AMC6821)	+= amc6821.o
 obj-$(CONFIG_SENSORS_THMC50)	+= thmc50.o
 obj-$(CONFIG_SENSORS_TMP102)	+= tmp102.o
+obj-$(CONFIG_SENSORS_TMP103)	+= tmp103.o
 obj-$(CONFIG_SENSORS_TMP401)	+= tmp401.o
 obj-$(CONFIG_SENSORS_TMP421)	+= tmp421.o
 obj-$(CONFIG_SENSORS_TWL4030_MADC)+= twl4030-madc-hwmon.o
diff --git a/drivers/hwmon/tmp103.c b/drivers/hwmon/tmp103.c
new file mode 100644
index 0000000..8d83033
--- /dev/null
+++ b/drivers/hwmon/tmp103.c
@@ -0,0 +1,203 @@
+/*
+ * Texas Instruments TMP103 SMBus temperature sensor driver
+ * Copyright (C) 2014 Heiko Schocher <hs@denx.de>
+ *
+ * Based on:
+ * Texas Instruments TMP102 SMBus temperature sensor driver
+ *
+ * Copyright (C) 2010 Steven King <sfking@fdwdc.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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/regmap.h>
+
+#define	DRIVER_NAME "tmp103"
+
+#define TMP103_TEMP_REG		0x00
+#define TMP103_CONF_REG		0x01
+#define TMP103_TLOW_REG		0x02
+#define TMP103_THIGH_REG	0x03
+
+#define TMP103_CONF_M0		0x01
+#define TMP103_CONF_M1		0x02
+#define TMP103_CONF_LC		0x04
+#define TMP103_CONF_FL		0x08
+#define TMP103_CONF_FH		0x10
+#define TMP103_CONF_CR0		0x20
+#define TMP103_CONF_CR1		0x40
+#define TMP103_CONF_ID		0x80
+#define TMP103_CONF_SD		(TMP103_CONF_M0 | TMP103_CONF_M1)
+
+#define TMP103_CONFIG		(TMP103_CONF_CR1 | TMP103_CONF_M1)
+
+static inline int tmp103_reg_to_mc(s8 val)
+{
+	return val * 1000;
+}
+
+static inline u8 tmp103_mc_to_reg(int val)
+{
+	return DIV_ROUND_CLOSEST(val, 1000);
+}
+
+static ssize_t tmp103_show_temp(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(regmap, sda->index, &regval);
+	if (ret < 0)
+		return ret;
+
+	return sprintf(buf, "%d\n", tmp103_reg_to_mc(regval));
+}
+
+static ssize_t tmp103_set_temp(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
+	struct regmap *regmap = dev_get_drvdata(dev);
+	long val;
+	int ret;
+
+	if (kstrtol(buf, 10, &val) < 0)
+		return -EINVAL;
+
+	val = clamp_val(val, -55000, 127000);
+	ret = regmap_write(regmap, sda->index, tmp103_mc_to_reg(val));
+	return ret ? ret : count;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp103_show_temp, NULL ,
+			  TMP103_TEMP_REG);
+
+static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, tmp103_show_temp,
+			  tmp103_set_temp, TMP103_TLOW_REG);
+
+static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp103_show_temp,
+			  tmp103_set_temp, TMP103_THIGH_REG);
+
+static struct attribute *tmp103_attrs[] = {
+	&sensor_dev_attr_temp1_input.dev_attr.attr,
+	&sensor_dev_attr_temp1_min.dev_attr.attr,
+	&sensor_dev_attr_temp1_max.dev_attr.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(tmp103);
+
+static bool tmp103_regmap_is_volatile(struct device *dev, unsigned int reg)
+{
+	return reg == TMP103_TEMP_REG;
+}
+
+static struct regmap_config tmp103_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = TMP103_THIGH_REG,
+	.volatile_reg = tmp103_regmap_is_volatile,
+};
+
+static int tmp103_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
+	struct regmap *regmap;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_BYTE_DATA)) {
+		dev_err(&client->dev,
+			"adapter doesn't support SMBus byte transactions\n");
+		return -ENODEV;
+	}
+
+	regmap = devm_regmap_init_i2c(client, &tmp103_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "failed to allocate register map\n");
+		return PTR_ERR(regmap);
+	}
+
+	ret = regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONFIG,
+				 TMP103_CONFIG);
+	if (ret < 0) {
+		dev_err(&client->dev, "error writing config register\n");
+		return ret;
+	}
+
+	hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
+						      regmap, tmp103_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+#ifdef CONFIG_PM
+static int tmp103_suspend(struct device *dev)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+
+	return regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONF_SD, 0);
+}
+
+static int tmp103_resume(struct device *dev)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+
+	return regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONF_SD,
+				  TMP103_CONF_SD);
+}
+
+static const struct dev_pm_ops tmp103_dev_pm_ops = {
+	.suspend	= tmp103_suspend,
+	.resume		= tmp103_resume,
+};
+
+#define TMP103_DEV_PM_OPS (&tmp103_dev_pm_ops)
+#else
+#define	TMP103_DEV_PM_OPS NULL
+#endif /* CONFIG_PM */
+
+static const struct i2c_device_id tmp103_id[] = {
+	{ DRIVER_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tmp103_id);
+
+static struct i2c_driver tmp103_driver = {
+	.driver = {
+		.name	= DRIVER_NAME,
+		.pm	= TMP103_DEV_PM_OPS,
+	},
+	.probe		= tmp103_probe,
+	.id_table	= tmp103_id,
+};
+
+module_i2c_driver(tmp103_driver);
+
+MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
+MODULE_DESCRIPTION("Texas Instruments TMP103 temperature sensor driver");
+MODULE_LICENSE("GPL");
-- 
1.8.3.1

Re: [PATCH v3] hwmon: Driver for TI TMP103 temperature sensor

[Guenter Roeck]

On 06/15/2014 11:47 PM, Heiko Schocher wrote:
> Driver for the TI TMP103.
>
> The TI TMP103 is similar to the TMP102.  It differs from the TMP102
> by having only 8 bit registers.
>
> Signed-off-by: Heiko Schocher <hs@denx.de>
>
Hello Heiko,

Almost there.

> ---
>
> +static int tmp103_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	struct device *dev = &client->dev;
> +	struct device *hwmon_dev;
> +	struct regmap *regmap;
> +	int ret;
> +
> +	if (!i2c_check_functionality(client->adapter,
> +				     I2C_FUNC_SMBUS_BYTE_DATA)) {
> +		dev_err(&client->dev,
> +			"adapter doesn't support SMBus byte transactions\n");
> +		return -ENODEV;
> +	}
> +
> +	regmap = devm_regmap_init_i2c(client, &tmp103_regmap_config);
> +	if (IS_ERR(regmap)) {
> +		dev_err(dev, "failed to allocate register map\n");
> +		return PTR_ERR(regmap);
> +	}
> +
> +	ret = regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONFIG,
> +				 TMP103_CONFIG);

You actually want to mask out CR0, CR1, M0, and M1 here.

> +	if (ret < 0) {
> +		dev_err(&client->dev, "error writing config register\n");
> +		return ret;
> +	}
> +
> +	hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
> +						      regmap, tmp103_groups);
> +	return PTR_ERR_OR_ZERO(hwmon_dev);
> +}
> +
> +#ifdef CONFIG_PM
> +static int tmp103_suspend(struct device *dev)
> +{
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +
> +	return regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONF_SD, 0);
> +}
> +
> +static int tmp103_resume(struct device *dev)
> +{
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +
> +	return regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONF_SD,
> +				  TMP103_CONF_SD);

That changes {M0, M1} to {1, 1}, but you really want {0, 1} to restore the
pre-suspend configuration.

One solution for both would be to define TMP103_CONFIG_MASK and TMP103_CONF_SD_MASK
separately to ensure you catch all the to-be-cleared bits.

Guenter