[v7] iio: temperature: Add driver support for Maxim MAX30208
Commit Message
Maxim MAX30208 is a digital temperature sensor with 0.1°C accuracy.
Add support for max30208 driver in iio subsystem.
Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX30208.pdf
Signed-off-by: Rajat Khandelwal <rajat.khandelwal@linux.intel.com>
---
v7:
1. Dropped GPIOs use for now
2. Driver name string directly used
3. Mutex lock description added
4. Removed noisy errors and only kept errors on larger code blocks
5. dev_warn -> dev_err for temperature conversion failure
6. Improvised the logic of popping out values
7. Fixed line breaks
8. module_i2c_driver
v6: Converted usleep_range to msleep as delay is quite large
v5:
1. Fixed comment position in max30208_request
2. Use of local u8 variable to build register values
3. Using u8 instead of s8 in data_count
4. Removed global MAX30208_RES_MILLICELCIUS
5. Removed 'comma' on NULL terminators
v4: Version comments go below line separator of signed-off-by
v3: Release the mutex lock after error gets returned
v2:
1. Removed TODO
2. Removed unnecessary blank spaces
3. Corrected MC->MILLICELCIUS
4. Comments added wherever required
5. dev_err on i2c fails
6. Rearranged some flows
7. Removed PROCESSED
8. int error return on gpio setup
9. device_register at the end of probe
10. Return on unsuccessful reset
11. acpi_match_table and of_match_table added
12. Minor quirks
MAINTAINERS | 6 +
drivers/iio/temperature/Kconfig | 10 ++
drivers/iio/temperature/Makefile | 1 +
drivers/iio/temperature/max30208.c | 220 +++++++++++++++++++++++++++++
4 files changed, 237 insertions(+)
create mode 100644 drivers/iio/temperature/max30208.c
Comments
Hi Rajat,
I love your patch! Perhaps something to improve:
[auto build test WARNING on jic23-iio/togreg]
[also build test WARNING on linus/master v6.1-rc3 next-20221104]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Rajat-Khandelwal/iio-temperature-Add-driver-support-for-Maxim-MAX30208/20221101-102308
base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
patch link: https://lore.kernel.org/r/20221101174409.316447-1-rajat.khandelwal%40linux.intel.com
patch subject: [PATCH v7] iio: temperature: Add driver support for Maxim MAX30208
config: riscv-randconfig-c006-20221103
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 791a7ae1ba3efd6bca96338e10ffde557ba83920)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install riscv cross compiling tool for clang build
# apt-get install binutils-riscv64-linux-gnu
# https://github.com/intel-lab-lkp/linux/commit/2375dabd39957ad8e80878c5604eda8a9f73932d
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Rajat-Khandelwal/iio-temperature-Add-driver-support-for-Maxim-MAX30208/20221101-102308
git checkout 2375dabd39957ad8e80878c5604eda8a9f73932d
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash drivers/block/ drivers/iio/temperature/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> drivers/iio/temperature/max30208.c:195:36: warning: unused variable 'max30208_acpi_match' [-Wunused-const-variable]
static const struct acpi_device_id max30208_acpi_match[] = {
^
1 warning generated.
vim +/max30208_acpi_match +195 drivers/iio/temperature/max30208.c
194
> 195 static const struct acpi_device_id max30208_acpi_match[] = {
196 { "MAX30208" },
197 { }
198 };
199 MODULE_DEVICE_TABLE(acpi, max30208_acpi_match);
200
On Fri, 4 Nov 2022 14:50:33 +0800
kernel test robot <lkp@intel.com> wrote:
> Hi Rajat,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on jic23-iio/togreg]
> [also build test WARNING on linus/master v6.1-rc3 next-20221104]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Rajat-Khandelwal/iio-temperature-Add-driver-support-for-Maxim-MAX30208/20221101-102308
> base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
> patch link: https://lore.kernel.org/r/20221101174409.316447-1-rajat.khandelwal%40linux.intel.com
> patch subject: [PATCH v7] iio: temperature: Add driver support for Maxim MAX30208
> config: riscv-randconfig-c006-20221103
> compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 791a7ae1ba3efd6bca96338e10ffde557ba83920)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install riscv cross compiling tool for clang build
> # apt-get install binutils-riscv64-linux-gnu
> # https://github.com/intel-lab-lkp/linux/commit/2375dabd39957ad8e80878c5604eda8a9f73932d
> git remote add linux-review https://github.com/intel-lab-lkp/linux
> git fetch --no-tags linux-review Rajat-Khandelwal/iio-temperature-Add-driver-support-for-Maxim-MAX30208/20221101-102308
> git checkout 2375dabd39957ad8e80878c5604eda8a9f73932d
> # save the config file
> mkdir build_dir && cp config build_dir/.config
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash drivers/block/ drivers/iio/temperature/
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/iio/temperature/max30208.c:195:36: warning: unused variable 'max30208_acpi_match' [-Wunused-const-variable]
> static const struct acpi_device_id max30208_acpi_match[] = {
> ^
> 1 warning generated.
>
See review comments on v6 that said to drop the use of ACPI_PTR(). It's not worth
the fiddly handling to save a trivial amount of data.
Jonathan
>
> vim +/max30208_acpi_match +195 drivers/iio/temperature/max30208.c
>
> 194
> > 195 static const struct acpi_device_id max30208_acpi_match[] = {
> 196 { "MAX30208" },
> 197 { }
> 198 };
> 199 MODULE_DEVICE_TABLE(acpi, max30208_acpi_match);
> 200
>
On Tue, 1 Nov 2022 23:14:09 +0530
Rajat Khandelwal <rajat.khandelwal@linux.intel.com> wrote:
> Maxim MAX30208 is a digital temperature sensor with 0.1°C accuracy.
>
> Add support for max30208 driver in iio subsystem.
> Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX30208.pdf
>
> Signed-off-by: Rajat Khandelwal <rajat.khandelwal@linux.intel.com>
Hi Rajat,
Given ongoing discussion on v6 (sorry I didn't get back to you earlier
in the week), will result in some changes in here, I'll wait for v8 before
taking another close look.
Jonathan
@@ -12373,6 +12373,12 @@ S: Maintained
F: Documentation/devicetree/bindings/regulator/maxim,max20086.yaml
F: drivers/regulator/max20086-regulator.c
+MAXIM MAX30208 TEMPERATURE SENSOR DRIVER
+M: Rajat Khandelwal <rajat.khandelwal@linux.intel.com>
+L: linux-iio@vger.kernel.org
+S: Maintained
+F: drivers/iio/temperature/max30208.c
+
MAXIM MAX77650 PMIC MFD DRIVER
M: Bartosz Golaszewski <brgl@bgdev.pl>
L: linux-kernel@vger.kernel.org
@@ -128,6 +128,16 @@ config TSYS02D
This driver can also be built as a module. If so, the module will
be called tsys02d.
+config MAX30208
+ tristate "Maxim MAX30208 digital temperature sensor"
+ depends on I2C
+ help
+ If you say yes here you get support for Maxim MAX30208
+ digital temperature sensor connected via I2C.
+
+ This driver can also be built as a module. If so, the module
+ will be called max30208.
+
config MAX31856
tristate "MAX31856 thermocouple sensor"
depends on SPI
@@ -7,6 +7,7 @@ obj-$(CONFIG_IQS620AT_TEMP) += iqs620at-temp.o
obj-$(CONFIG_LTC2983) += ltc2983.o
obj-$(CONFIG_HID_SENSOR_TEMP) += hid-sensor-temperature.o
obj-$(CONFIG_MAXIM_THERMOCOUPLE) += maxim_thermocouple.o
+obj-$(CONFIG_MAX30208) += max30208.o
obj-$(CONFIG_MAX31856) += max31856.o
obj-$(CONFIG_MAX31865) += max31865.o
obj-$(CONFIG_MLX90614) += mlx90614.o
new file mode 100644
@@ -0,0 +1,220 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (c) Rajat Khandelwal <rajat.khandelwal@linux.intel.com>
+ *
+ * Maxim MAX30208 digital temperature sensor with 0.1°C accuracy
+ * (7-bit I2C slave address (0x50 - 0x53))
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#define MAX30208_STATUS 0x00
+#define MAX30208_STATUS_TEMP_RDY BIT(0)
+#define MAX30208_INT_ENABLE 0x01
+#define MAX30208_INT_ENABLE_TEMP_RDY BIT(0)
+
+#define MAX30208_FIFO_OVF_CNTR 0x06
+#define MAX30208_FIFO_DATA_CNTR 0x07
+#define MAX30208_FIFO_DATA 0x08
+
+#define MAX30208_SYSTEM_CTRL 0x0c
+#define MAX30208_SYSTEM_CTRL_RESET 0x01
+
+#define MAX30208_TEMP_SENSOR_SETUP 0x14
+#define MAX30208_TEMP_SENSOR_SETUP_CONV BIT(0)
+
+struct max30208_data {
+ struct i2c_client *client;
+ struct iio_dev *indio_dev;
+ struct mutex lock; /* Lock to prevent concurrent reads of temperature readings */
+};
+
+static const struct iio_chan_spec max30208_channels[] = {
+ {
+ .type = IIO_TEMP,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+ },
+};
+
+/**
+ * max30208_request() - Request a reading
+ * @data: Struct comprising member elements of the device
+ *
+ * Requests a reading from the device and waits until the conversion is ready.
+ */
+static int max30208_request(struct max30208_data *data)
+{
+ /*
+ * Sensor can take up to 500 ms to respond so execute a total of
+ * 10 retries to give the device sufficient time.
+ */
+ int retries = 10;
+ u8 regval;
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, MAX30208_TEMP_SENSOR_SETUP);
+ if (ret < 0)
+ return ret;
+
+ regval = ret | MAX30208_TEMP_SENSOR_SETUP_CONV;
+
+ ret = i2c_smbus_write_byte_data(data->client, MAX30208_TEMP_SENSOR_SETUP, regval);
+ if (ret)
+ return ret;
+
+ while (retries--) {
+ ret = i2c_smbus_read_byte_data(data->client, MAX30208_STATUS);
+ if (ret < 0)
+ return ret;
+
+ if (ret & MAX30208_STATUS_TEMP_RDY)
+ return 0;
+
+ msleep(50);
+ }
+ dev_err(&data->client->dev, "Temperature conversion failed, reporting the last known reading...\n");
+
+ return 0;
+}
+
+static int max30208_update_temp(struct max30208_data *data)
+{
+ u8 data_count;
+ int ret;
+
+ mutex_lock(&data->lock);
+
+ ret = max30208_request(data);
+ if (ret)
+ goto unlock;
+
+ ret = i2c_smbus_read_byte_data(data->client, MAX30208_FIFO_OVF_CNTR);
+ if (ret < 0)
+ goto unlock;
+ else if (!ret) {
+ ret = i2c_smbus_read_byte_data(data->client, MAX30208_FIFO_DATA_CNTR);
+ if (ret < 0)
+ goto unlock;
+ }
+
+ data_count = ret;
+
+ while (data_count) {
+ ret = i2c_smbus_read_word_swapped(data->client, MAX30208_FIFO_DATA);
+ if (ret < 0)
+ goto unlock;
+
+ data_count--;
+ }
+
+unlock:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int max30208_read(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct max30208_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = max30208_update_temp(data);
+ if (ret < 0)
+ return ret;
+
+ *val = sign_extend32(ret, 15);
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ *val = 5;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info max30208_info = {
+ .read_raw = max30208_read,
+};
+
+static int max30208_probe(struct i2c_client *i2c)
+{
+ struct device *dev = &i2c->dev;
+ struct max30208_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ data->client = i2c;
+ mutex_init(&data->lock);
+
+ indio_dev->name = "max30208";
+ indio_dev->channels = max30208_channels;
+ indio_dev->num_channels = ARRAY_SIZE(max30208_channels);
+ indio_dev->info = &max30208_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = i2c_smbus_write_byte_data(data->client, MAX30208_SYSTEM_CTRL,
+ MAX30208_SYSTEM_CTRL_RESET);
+ if (ret) {
+ dev_err(dev, "Failure in performing reset\n");
+ return ret;
+ }
+
+ msleep(50);
+
+ ret = devm_iio_device_register(dev, indio_dev);
+ if (ret) {
+ dev_err(dev, "Failed to register IIO device\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct i2c_device_id max30208_id_table[] = {
+ { "max30208" },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max30208_id_table);
+
+static const struct acpi_device_id max30208_acpi_match[] = {
+ { "MAX30208" },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, max30208_acpi_match);
+
+static const struct of_device_id max30208_of_match[] = {
+ { .compatible = "maxim,max30208" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, max30208_of_match);
+
+static struct i2c_driver max30208_driver = {
+ .driver = {
+ .name = "max30208",
+ .of_match_table = max30208_of_match,
+ .acpi_match_table = ACPI_PTR(max30208_acpi_match),
+ },
+ .probe_new = max30208_probe,
+ .id_table = max30208_id_table,
+};
+module_i2c_driver(max30208_driver);
+
+MODULE_AUTHOR("Rajat Khandelwal <rajat.khandelwal@linux.intel.com>");
+MODULE_DESCRIPTION("Maxim MAX30208 digital temperature sensor");
+MODULE_LICENSE("GPL");