lkml.org 
[lkml]   [2011]   [May]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCHv2 -next] HWMON: HWMON module of DA9052 PMIC driver
On Wed, May 04, 2011 at 06:36:55AM -0400, Ashish Jangam wrote:
> Hi,
>
> HWMON Driver for Dialog Semiconductor DA9052 PMICs.
>
> Changes made since last submission:
> . Removed battery temperature parameter as it involves logarithm and floating point operation.
>
Hi David/Ashish,

Why don't you approximate that calculation with fixed point operations ?

Unless my math is bad, ln(x) = log2(x) * ln(2) = log2(x) * 0.693147181

and you can use ilog2() to calculate log2(x).

> Signed-off-by: David Dajun Chen <dchen@diasemi.com>
> ---
>
> diff -Naur linux-next-20110421.orig/Documentation/hwmon/da9052 linux-next-20110421/Documentation/hwmon/da9052
> --- linux-next-20110421.orig/Documentation/hwmon/da9052 1970-01-01 05:00:00.000000000 +0500
> +++ linux-next-20110421/Documentation/hwmon/da9052 2011-05-04 14:11:56.000000000 +0500
> @@ -0,0 +1,61 @@
> +Kernel driver da9052-hwmon
> +==========================
> +
> +Supported chips:
> + * Dialog Semiconductors DA9052 PMICs
> + Prefix: 'da9052'
> + Datasheet: Kindly visit www.dialog-semiconductor.com and request for the
> + official datasheet.
> +
> +Authors: David Dajun Chen <dchen@diasemi.com>
> +
> +Description
> +-----------
> +
> +The DA9052 provides an Analogue to Digital Converter (ADC) with 10 bits
> +resolution and track and hold circuitry combined with an analogue input
> +multiplexer. The analogue input multiplexer will allow conversion of up to 10
> +different inputs. The track and hold circuit ensures stable input voltages at
> +the input of the ADC during the conversion.
> +
> +The ADC is used to measure the following inputs:
> +Channel 0: VDDOUT - measurement of the system voltage
> +Channel 1: ICH - internal battery charger current measurement
> +Channel 2: TBAT - output from the battery NTC
> +Channel 3: VBAT - measurement of the battery voltage
> +Channel 4: ADC_IN4 - high impedance input (0 - 2.5V)
> +Channel 5: ADC_IN5 - high impedance input (0 - 2.5V)
> +Channel 6: ADC_IN6 - high impedance input (0 - 2.5V)
> +Channel 7: XY - TSI interface to measure the X and Y voltage of the touch
> +screen resistive potentiometers
> +Channel 8: Internal Tjunc. - sense (internal temp. sensor)
> +Channel 9: VBBAT - measurement of the backup battery voltage
> +
> +By using sysfs attributes we can measure the system voltage VDDOUT, the battery
> +charging current ICH, battery temperature TBAT, battery junction temperature
> +TJUNC, battery voltage VBAT and the back up battery voltage VBBAT.
> +
> +Voltage Monitoring
> +------------------
> +
> +Voltages are sampled by a 10 bit ADC. Voltages in millivolts are 1.465
> +times the ADC value.
> +
> +Temperature Monitoring
> +----------------------
> +
> +Temperatures are sampled by a 10 bit ADC. Junction and battery temperatures
> +are monitored by the ADC channels.
> +
> +The junction temperature is calculated:
> + Degrees celsius = 1.708 * (TJUNC_RES - T_OFFSET) - 108.8
> +The junction temperature attribute is supported by the driver.
> +
> +The battery temperature is calculated:
> + Degree Celcius = 1 / (t1 + 1/298)- 273
> +where t1 = (1/B)* ln(( ADCval * 2.5)/(R25*ITBAT*255))
> +Default values of R25, B, ITBAT are 10e3, 3380 and 50e-6 respectively.
> +As the battery temperature computation depends on floating point
> +computation and taking natural log the battery temperature attribute is
> +not supported by the driver.
> +
> diff -Naur linux-next-20110421.orig/drivers/hwmon/da9052-hwmon.c linux-next-20110421/drivers/hwmon/da9052-hwmon.c
> --- linux-next-20110421.orig/drivers/hwmon/da9052-hwmon.c 1970-01-01 05:00:00.000000000 +0500
> +++ linux-next-20110421/drivers/hwmon/da9052-hwmon.c 2011-05-04 14:12:13.000000000 +0500
> @@ -0,0 +1,317 @@
> +/*
> + * HWMON Driver for Dialog DA9052
> + *
> + * Copyright(c) 2011 Dialog Semiconductor Ltd.
> + *
> + * Author: David Dajun Chen <dchen@diasemi.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.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/hwmon.h>
> +#include <linux/slab.h>
> +#include <linux/init.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/platform_device.h>
> +
> +#include <linux/mfd/da9052/da9052.h>
> +#include <linux/mfd/da9052/reg.h>
> +
> +struct da9052_hwmon {
> + struct da9052 *da9052;
> + struct device *class_device;
> + struct mutex hwmon_lock;
> +};
> +static const char * const input_names[] = {
> + [DA9052_ADC_VDDOUT] = "VDDOUT",
> + [DA9052_ADC_ICH] = "CHARGING CURRENT",
> + [DA9052_ADC_VBAT] = "BATTERY VOLTAGE",
> + [DA9052_ADC_IN4] = "ADC IN4",
> + [DA9052_ADC_IN5] = "ADC IN5",
> + [DA9052_ADC_IN6] = "ADC IN6",
> + [DA9052_ADC_TJUNC] = "BATTERY JUNCTION TEMP",
> + [DA9052_ADC_VBBAT] = "BACK-UP BATTERY VOLTAGE",
> +};
> +
> +static int da9052_enable_vddout_channel(struct da9052 *da9052)
> +{
> + int ret;
> +
> + ret = da9052_reg_read(da9052, DA9052_ADC_CONT_REG);
> + if (ret < 0)
> + return ret;
> +
> + ret |= DA9052_ADCCONT_AUTOVDDEN;
> + return da9052_reg_write(da9052, DA9052_ADC_CONT_REG, ret);
> +}
> +
> +static int da9052_disable_vddout_channel(struct da9052 *da9052)
> +{
> + int ret;
> +
> + ret = da9052_reg_read(da9052, DA9052_ADC_CONT_REG);
> + if (ret < 0)
> + return ret;
> +
> + ret &= ~DA9052_ADCCONT_AUTOVDDEN;
> + return da9052_reg_write(da9052, DA9052_ADC_CONT_REG, ret);
> +
> +}
> +
> +static ssize_t da9052_read_vddout(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int ret;
> +
> + mutex_lock(&hwmon->hwmon_lock);
> +
> + ret = da9052_enable_vddout_channel(hwmon->da9052);
> + if (ret < 0)
> + goto hwmon_err;
> +
> + ret = da9052_reg_read(hwmon->da9052, DA9052_VDD_RES_REG);
> + if (ret < 0)
> + pr_err("failed to read VDD_RES_REG\n");
> +
... this means the error will be ignored.

> + ret = da9052_disable_vddout_channel(hwmon->da9052);
> + if (ret < 0)
> + goto hwmon_err;
> +
> + mutex_unlock(&hwmon->hwmon_lock);
> + return sprintf(buf, "%d\n", ret);

... and this will print the return value from da9052_disable_vddout_channel(),
not the vddout value.

> +hwmon_err:
> + mutex_unlock(&hwmon->hwmon_lock);
> + return ret;
> +}
> +
> +static ssize_t da9052_read_ich(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = da9052_reg_read(hwmon->da9052, DA9052_ICHG_AV_REG);
> + if (ret < 0)
> + return ret;
> +
> + /* Equivalent to 3.9mA/bit in register ICHG_AV */
> + ret = DIV_ROUND_CLOSEST(ret * 39, 10);
> + return sprintf(buf, "%d\n", ret);
> +}
> +
> +static ssize_t da9052_read_vbat(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = da9052_adc_manual_read(hwmon->da9052, DA9052_ADC_VBAT);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%d\n", ret);
> +}
> +
> +static ssize_t da9052_read_misc_channel(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int channel = to_sensor_dev_attr(devattr)->index;
> + int ret;
> +
> + ret = da9052_adc_manual_read(hwmon->da9052, channel);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%d\n", ret);
> +}
> +
> +static ssize_t da9052_read_tjunc(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int temp;
> + int ret;
> +
> + ret = da9052_reg_read(hwmon->da9052, DA9052_TJUNC_RES_REG);
> + if (ret < 0)
> + return ret;
> +
> + temp = ret;
> +
> + ret = da9052_reg_read(hwmon->da9052, DA9052_T_OFFSET_REG);
> + if (ret < 0)
> + return ret;
> +
> + /* Degrees celsius = 1.708 * (TJUNC_RES - T_OFFSET) - 108.8 */
> + ret = 1708 * (temp - ret) - 108800;
> + return sprintf(buf, "%d\n", ret);
> +}
> +
> +static ssize_t da9052_read_vbbat(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = da9052_adc_manual_read(hwmon->da9052, DA9052_ADC_VBBAT);
> + if (ret < 0)
> + return ret;
> +
> + return sprintf(buf, "%d\n", ret);
> +
> +}
> +
> +static ssize_t da9052_hwmon_show_name(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + return sprintf(buf, "da9052-hwmon\n");
> +}
> +
> +static ssize_t show_label(struct device *dev,
> + struct device_attribute *devattr, char *buf)
> +{
> + return sprintf(buf, "%s\n",
> + input_names[to_sensor_dev_attr(devattr)->index]);
> +}
> +
> +static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, da9052_read_vddout, NULL,
> + DA9052_ADC_ICH);
> +static SENSOR_DEVICE_ATTR(in0_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_ICH);
> +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, da9052_read_vbat, NULL,
> + DA9052_ADC_VBAT);
> +static SENSOR_DEVICE_ATTR(in3_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_VBAT);
> +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, da9052_read_misc_channel, NULL,
> + DA9052_ADC_IN4);
> +static SENSOR_DEVICE_ATTR(in4_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_IN4);
> +static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, da9052_read_misc_channel, NULL,
> + DA9052_ADC_IN5);
> +static SENSOR_DEVICE_ATTR(in5_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_IN5);
> +static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, da9052_read_misc_channel, NULL,
> + DA9052_ADC_IN6);
> +static SENSOR_DEVICE_ATTR(in6_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_IN6);
> +static SENSOR_DEVICE_ATTR(in9_input, S_IRUGO, da9052_read_vbbat, NULL,
> + DA9052_ADC_VBBAT);
> +static SENSOR_DEVICE_ATTR(in9_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_VBBAT);
> +static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, da9052_read_ich, NULL,
> + DA9052_ADC_ICH);
> +static SENSOR_DEVICE_ATTR(curr1_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_TJUNC);
> +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, da9052_read_tjunc, NULL,
> + DA9052_ADC_TJUNC);
> +static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
> + DA9052_ADC_TJUNC);
> +
> +static DEVICE_ATTR(name, S_IRUGO, da9052_hwmon_show_name, NULL);
> +
> +static struct attribute *da9052_attr[] = {
> + &dev_attr_name.attr,
> +
> + &sensor_dev_attr_in0_input.dev_attr.attr,
> + &sensor_dev_attr_in0_label.dev_attr.attr,
> + &sensor_dev_attr_curr1_input.dev_attr.attr,
> + &sensor_dev_attr_curr1_label.dev_attr.attr,
> + &sensor_dev_attr_temp1_input.dev_attr.attr,
> + &sensor_dev_attr_temp1_label.dev_attr.attr,
> + &sensor_dev_attr_in3_input.dev_attr.attr,
> + &sensor_dev_attr_in3_label.dev_attr.attr,
> + &sensor_dev_attr_in4_input.dev_attr.attr,
> + &sensor_dev_attr_in4_label.dev_attr.attr,
> + &sensor_dev_attr_in5_input.dev_attr.attr,
> + &sensor_dev_attr_in5_label.dev_attr.attr,
> + &sensor_dev_attr_in6_input.dev_attr.attr,
> + &sensor_dev_attr_in6_label.dev_attr.attr,
> + &sensor_dev_attr_temp1_input.dev_attr.attr,
> + &sensor_dev_attr_temp1_label.dev_attr.attr,
> + &sensor_dev_attr_in9_input.dev_attr.attr,
> + &sensor_dev_attr_in9_label.dev_attr.attr,
> + NULL
> +};
> +
> +static const struct attribute_group da9052_attr_group = {.attrs = da9052_attr};
> +
> +static int __init da9052_hwmon_probe(struct platform_device *pdev)
> +{
> + struct da9052_hwmon *hwmon;
> + int ret;
> +
> + hwmon = kzalloc(sizeof(struct da9052_hwmon), GFP_KERNEL);
> + if (!hwmon)
> + return -ENOMEM;
> +
> + mutex_init(&hwmon->hwmon_lock);
> + hwmon->da9052 = dev_get_drvdata(pdev->dev.parent);
> +
> + platform_set_drvdata(pdev, hwmon);
> +
> + ret = sysfs_create_group(&pdev->dev.kobj, &da9052_attr_group);
> + if (ret)
> + goto err_mem;
> +
> + hwmon->class_device = hwmon_device_register(&pdev->dev);
> + if (IS_ERR(hwmon->class_device)) {
> + ret = PTR_ERR(hwmon->class_device);
> + goto err_mem;

You need to clean up the sysfs entries.

> + }
> +
> + return 0;
> +
> +err_mem:
> + kfree(hwmon);
> + return ret;
> +}
> +
> +static int __devexit da9052_hwmon_remove(struct platform_device *pdev)
> +{
> + struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
> +
> + hwmon_device_unregister(hwmon->class_device);
> + sysfs_remove_group(&pdev->dev.kobj, &da9052_attr_group);
> + mutex_destroy(&hwmon->hwmon_lock);
> + kfree(hwmon);
> +
> + return 0;
> +}
> +
> +static struct platform_driver da9052_hwmon_driver = {
> + .driver = {
> + .name = "da9052-hwmon",
> + .owner = THIS_MODULE,
> + },
> + .probe = da9052_hwmon_probe,
> + .remove = __devexit_p(da9052_hwmon_remove),
> +
> +};
> +
> +static int __init da9052_hwmon_init(void)
> +{
> +
> + return platform_driver_register(&da9052_hwmon_driver);
> +}
> +module_init(da9052_hwmon_init);
> +
> +static void __exit da9052_hwmon_exit(void)
> +{
> + platform_driver_unregister(&da9052_hwmon_driver);
> +}
> +module_exit(da9052_hwmon_exit);
> +
> +MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
> +MODULE_DESCRIPTION("DA9052 HWMON driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:da9052-hwmon");
> diff -Naur linux-next-20110421.orig/drivers/hwmon/Kconfig linux-next-20110421/drivers/hwmon/Kconfig
> --- linux-next-20110421.orig/drivers/hwmon/Kconfig 2011-04-26 09:31:34.000000000 +0500
> +++ linux-next-20110421/drivers/hwmon/Kconfig 2011-05-04 14:10:00.000000000 +0500
> @@ -303,6 +303,16 @@
> This driver can also be built as a module. If so, the module
> will be called ds1621.
>
> +config SENSORS_DA9052_ADC
> + tristate "Dialog DA9052 HWMON"
> + depends on PMIC_DA9052
> + help
> + Say y here to support the ADC found on
> + Dialog Semiconductor DA9052 PMIC.
> +
> + This driver can also be built as module. If so, the module
> + will be called da9052-hwmon.
> +
> config SENSORS_I5K_AMB
> tristate "FB-DIMM AMB temperature sensor on Intel 5000 series chipsets"
> depends on PCI && EXPERIMENTAL
> diff -Naur linux-next-20110421.orig/drivers/hwmon/Makefile linux-next-20110421/drivers/hwmon/Makefile
> --- linux-next-20110421.orig/drivers/hwmon/Makefile 2011-04-26 09:31:34.000000000 +0500
> +++ linux-next-20110421/drivers/hwmon/Makefile 2011-05-04 14:10:00.000000000 +0500
> @@ -41,6 +41,7 @@
> obj-$(CONFIG_SENSORS_ATXP1) += atxp1.o
> obj-$(CONFIG_SENSORS_CORETEMP) += coretemp.o
> obj-$(CONFIG_SENSORS_PKGTEMP) += pkgtemp.o
> +obj-$(CONFIG_SENSORS_DA9052_ADC)+= da9052-hwmon.o
> obj-$(CONFIG_SENSORS_DME1737) += dme1737.o
> obj-$(CONFIG_SENSORS_DS620) += ds620.o
> obj-$(CONFIG_SENSORS_DS1621) += ds1621.o
>
> Regards,
> Ashish
>
>


\
 
 \ /
  Last update: 2011-05-04 16:25    [W:0.050 / U:0.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site