[PATCH 0/2] Add support for MAX1721x fuel gauge chips

[PATCH 0/2] Add support for MAX1721x fuel gauge chips

[Alex A. Mihaylov]

Maxim Semiconductor MAX17211/MAX17215 is M5 Fuel Gauge Monitor with
OneWire (W1) interface.

This patch provide W1 family, MAX17211x slave device and MAX17211x
battery power_supply class device.

Alex A. Mihaylov (2):
  Add support for OneWire (W1) devices family 0x26 (MAX17211/MAX17215)
  Add driver for MAX17211/MAX17215 fuel gauge

 drivers/power/supply/Kconfig            |   8 +
 drivers/power/supply/Makefile           |   1 +
 drivers/power/supply/max1721x_battery.c | 303 ++++++++++++++++++++++++++++++++
 drivers/w1/slaves/Kconfig               |  12 ++
 drivers/w1/slaves/Makefile              |   1 +
 drivers/w1/slaves/w1_max1721x.c         | 121 +++++++++++++
 drivers/w1/slaves/w1_max1721x.h         | 101 +++++++++++
 drivers/w1/w1_family.h                  |   1 +
 8 files changed, 548 insertions(+)
 create mode 100644 drivers/power/supply/max1721x_battery.c
 create mode 100644 drivers/w1/slaves/w1_max1721x.c
 create mode 100644 drivers/w1/slaves/w1_max1721x.h

-- 
2.8.4 (Apple Git-73)

[PATCH 1/2] Add support for OneWire (W1) devices family 0x26 (MAX17211/MAX17215)

[Alex A. Mihaylov]

Maxim Semiconductor MAX17211/MAX17215 single/multi-cell fuel gauge
monitor with M5 Fuel Gauge algorithm

Slave device provide software layer for access to internal registers
MAX17211/MAX17215 chip.
---
 drivers/w1/slaves/Kconfig       |  12 ++++
 drivers/w1/slaves/Makefile      |   1 +
 drivers/w1/slaves/w1_max1721x.c | 121 ++++++++++++++++++++++++++++++++++++++++
 drivers/w1/slaves/w1_max1721x.h | 101 +++++++++++++++++++++++++++++++++
 drivers/w1/w1_family.h          |   1 +
 5 files changed, 236 insertions(+)
 create mode 100644 drivers/w1/slaves/w1_max1721x.c
 create mode 100644 drivers/w1/slaves/w1_max1721x.h

diff --git a/drivers/w1/slaves/Kconfig b/drivers/w1/slaves/Kconfig
index cfe74d0..05467da 100644
--- a/drivers/w1/slaves/Kconfig
+++ b/drivers/w1/slaves/Kconfig
@@ -78,6 +78,18 @@ config W1_SLAVE_DS2433_CRC
 	  Each block has 30 bytes of data and a two byte CRC16.
 	  Full block writes are only allowed if the CRC is valid.
 
+config W1_SLAVE_MAX1721X
+	tristate "Maxim MAX17211/MAX17215 battery monitor chip"
+	help
+	  If you enable this you will have the MAX17211/MAX17215 battery
+	  monitor chip support.
+
+	  The battery monitor chip is used in many batteries/devices
+	  as the one who is responsible for charging/discharging/monitoring
+	  Li+ batteries.
+
+	  If you are unsure, say N.
+
 config W1_SLAVE_DS2760
 	tristate "Dallas 2760 battery monitor chip (HP iPAQ & others)"
 	help
diff --git a/drivers/w1/slaves/Makefile b/drivers/w1/slaves/Makefile
index 1e9989a..1e9f942 100644
--- a/drivers/w1/slaves/Makefile
+++ b/drivers/w1/slaves/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_W1_SLAVE_DS2406)	+= w1_ds2406.o
 obj-$(CONFIG_W1_SLAVE_DS2423)	+= w1_ds2423.o
 obj-$(CONFIG_W1_SLAVE_DS2431)	+= w1_ds2431.o
 obj-$(CONFIG_W1_SLAVE_DS2433)	+= w1_ds2433.o
+obj-$(CONFIG_W1_SLAVE_MAX1721X)	+= w1_max1721x.o
 obj-$(CONFIG_W1_SLAVE_DS2760)	+= w1_ds2760.o
 obj-$(CONFIG_W1_SLAVE_DS2780)	+= w1_ds2780.o
 obj-$(CONFIG_W1_SLAVE_DS2781)	+= w1_ds2781.o
diff --git a/drivers/w1/slaves/w1_max1721x.c b/drivers/w1/slaves/w1_max1721x.c
new file mode 100644
index 0000000..bb73e90
--- /dev/null
+++ b/drivers/w1/slaves/w1_max1721x.c
@@ -0,0 +1,121 @@
+/*
+ * 1-Wire implementation for the max17211 chip
+ *
+ * Copyright © 2017, Alex A. Mihaylov <minimumlaw@rambler.ru>
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/idr.h>
+#include <linux/gfp.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+#include "../w1_family.h"
+#include "w1_max1721x.h"
+
+int w1_max1721x_reg_get(struct device *dev, uint16_t addr, uint16_t *val)
+{
+	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+	int ret = -ENODEV;
+
+	if (addr > MAX1721X_MAX_REG_NR || addr < 0 || !val || !dev)
+		return -EFAULT;
+
+	mutex_lock(&sl->master->bus_mutex);
+
+	if (!w1_reset_select_slave(sl)) {
+		w1_write_8(sl->master, W1_MAX1721X_READ_DATA);
+		w1_write_8(sl->master, addr & 0x00FF);
+		w1_write_8(sl->master, addr>>8 & 0x00FF);
+		*val = w1_read_8(sl->master);
+		*val |= w1_read_8(sl->master)<<8;
+		ret = 0;
+	}
+
+	mutex_unlock(&sl->master->bus_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL(w1_max1721x_reg_get);
+
+int w1_max1721x_reg_set(struct device *dev, uint16_t addr, uint16_t val)
+{
+	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+	int ret = -ENODEV;
+
+	if (addr > MAX1721X_MAX_REG_NR || addr < 0 || !dev)
+		return -EFAULT;
+
+	mutex_lock(&sl->master->bus_mutex);
+
+	if (!w1_reset_select_slave(sl)) {
+		w1_write_8(sl->master, W1_MAX1721X_READ_DATA);
+		w1_write_8(sl->master, addr & 0x00FF);
+		w1_write_8(sl->master, addr>>8 & 0x00FF);
+		w1_write_8(sl->master, val & 0x00FF);
+		w1_write_8(sl->master, val>>8 & 0x00FF);
+		ret = 0;
+	}
+
+	mutex_unlock(&sl->master->bus_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL(w1_max1721x_reg_set);
+
+static int w1_max17211_add_device(struct w1_slave *sl)
+{
+	int ret;
+	struct platform_device *pdev;
+
+	pdev = platform_device_alloc("max1721x-battery", PLATFORM_DEVID_AUTO);
+	if (!pdev)
+		return -ENOMEM;
+	pdev->dev.parent = &sl->dev;
+
+	ret = platform_device_add(pdev);
+	if (ret)
+		goto pdev_add_failed;
+
+	dev_set_drvdata(&sl->dev, pdev);
+
+	return 0;
+
+pdev_add_failed:
+	platform_device_put(pdev);
+
+	return ret;
+}
+
+static void w1_max17211_remove_device(struct w1_slave *sl)
+{
+	struct platform_device *pdev = dev_get_drvdata(&sl->dev);
+
+	platform_device_unregister(pdev);
+}
+
+static struct w1_family_ops w1_max17211_fops = {
+	.add_slave    = w1_max17211_add_device,
+	.remove_slave = w1_max17211_remove_device,
+};
+
+static struct w1_family w1_max17211_family = {
+	.fid = W1_FAMILY_MAX17211,
+	.fops = &w1_max17211_fops,
+};
+module_w1_family(w1_max17211_family);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alex A. Mihaylov <minimumlaw@rambler.ru>");
+MODULE_DESCRIPTION("1-wire Driver for MAX17211/MAX17215 battery monitor");
+MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_MAX17211));
diff --git a/drivers/w1/slaves/w1_max1721x.h b/drivers/w1/slaves/w1_max1721x.h
new file mode 100644
index 0000000..1deb3d3
--- /dev/null
+++ b/drivers/w1/slaves/w1_max1721x.h
@@ -0,0 +1,101 @@
+/*
+ * 1-Wire implementation for the max17211 chip
+ *
+ * Copyright © 2017, Alex A. Mihaylov <minimumlaw@rambler.ru>
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ *
+ */
+
+#ifndef __w1_max17211_h__
+#define __w1_max17211_h__
+
+/* Known commands to the MAX1721X chip */
+#define W1_MAX1721X_READ_DATA		0x69
+#define W1_MAX1721X_WRITE_DATA		0x6C
+
+/* Factory settings (nonvilatile registers) (W1 specific) */
+
+#define MAX1721X_REG_NRSENSE	0x1CF	/* RSense in 10^-5 Ohm */
+/* Strings */
+#define MAX1721X_REG_MFG_STR	0x1CC
+#define MAX1721X_REG_MFG_NUMB	3
+#define MAX1721X_REG_DEV_STR	0x1DB
+#define MAX1721X_REG_DEV_NUMB	5
+/* HEX Strings */
+#define MAX1721X_REG_SER_HEX	0x1D8
+
+/* Number of valid register addresses */
+#define MAX1721X_MAX_REG_NR	(0x1EF)
+
+/* MAX1721X/MAX17215 Output Registers for I2C and W1 chips */
+
+#define MAX172XX_REG_STATUS	0x000	/* status reg */
+#define MAX172XX_BAT_PRESENT	(1<<4)	/* battery connected bit */
+#define MAX172XX_REG_DEVNAME	0x021	/* chip config */
+#define MAX172XX_DEV_MASK	0x000F	/* chip type mask */
+#define MAX172X1_DEV		0x0001
+#define MAX172X5_DEV		0x0005
+#define MAX172XX_REG_TEMP	0x008	/* Temperature */
+#define MAX172XX_REG_BATT	0x0DA	/* Battery voltage */
+#define MAX172XX_REG_CURRENT	0x00A	/* Actual current */
+#define MAX172XX_REG_AVGCURRENT	0x00B	/* Average current */
+#define MAX172XX_REG_REPSOC	0x006	/* Percentage of charge */
+#define MAX172XX_REG_DESIGNCAP	0x018	/* Design capacity */
+#define MAX172XX_REG_REPCAP	0x005	/* Average capacity */
+#define MAX172XX_REG_TTE	0x011	/* Time to empty */
+#define MAX172XX_REG_TTF	0x020	/* Time to full */
+
+/* Convert regs value to power_supply units */
+
+static inline int max172xx_time_to_ps(uint16_t reg)
+{
+	return reg * 5625 / 1000;	/* in sec. */
+}
+
+static inline int max172xx_percent_to_ps(uint16_t reg)
+{
+	return reg / 256;	/* in percent from 0 to 100 */
+}
+
+static inline int max172xx_voltage_to_ps(uint16_t reg)
+{
+	return reg * 1250;	/* in uV */
+}
+
+static inline int max172xx_capacity_to_ps(uint16_t reg)
+{
+	return reg * 500;	/* in uAh */
+}
+
+/*
+ * Current and temperature is signed values, so unsigned regs
+ * value must be converted to signed type
+ */
+
+static inline int max172xx_temperature_to_ps(uint16_t reg)
+{
+	return (int16_t)reg * 10 / 256;	/* in tenths of deg. C */
+}
+
+/*
+ * Calculating current registers resolution:
+ *
+ * RSense stored in 10^-5 Ohm, so mesaurment voltage must be
+ * in 10^-11 Volts for get current in uA.
+ * 16 bit current reg fullscale +/-51.2mV is 102400 uV.
+ * So: 102400 / 65535 * 10^5 = 156252
+ */
+static inline int max172xx_current_to_voltage(uint16_t reg)
+{
+	return (int16_t)reg * 156252;
+}
+
+extern int w1_max1721x_reg_get(struct device *dev, uint16_t addr,
+			uint16_t *val);
+extern int w1_max1721x_reg_set(struct device *dev, uint16_t addr,
+			uint16_t val);
+
+#endif /* !__w1_max17211_h__ */
diff --git a/drivers/w1/w1_family.h b/drivers/w1/w1_family.h
index 10a7a07..797c162 100644
--- a/drivers/w1/w1_family.h
+++ b/drivers/w1/w1_family.h
@@ -35,6 +35,7 @@
 #define W1_COUNTER_DS2423	0x1D
 #define W1_THERM_DS1822  	0x22
 #define W1_EEPROM_DS2433  	0x23
+#define W1_FAMILY_MAX17211	0x26
 #define W1_THERM_DS18B20 	0x28
 #define W1_FAMILY_DS2408	0x29
 #define W1_EEPROM_DS2431	0x2D
-- 
2.8.4 (Apple Git-73)

Re: [PATCH 1/2] Add support for OneWire (W1) devices family 0x26 (MAX17211/MAX17215)

[Sebastian Reichel]

[-- Attachment #1: Type: text/plain, Size: 710 bytes --]

Hi,

On Sat, Apr 29, 2017 at 05:34:28PM +0300, Alex A. Mihaylov wrote:
> Maxim Semiconductor MAX17211/MAX17215 single/multi-cell fuel gauge
> monitor with M5 Fuel Gauge algorithm
> 
> Slave device provide software layer for access to internal registers
> MAX17211/MAX17215 chip.

Please convert this to regmap. There should be lots of docs and
examples around, for example:

http://elinux.org/images/a/a3/Regmap-_The_Power_of_Subsystems_and_Abstractions.pdf

There is no generic w1 handler, but you can provide custom
read/write functions. Also it would be nice to have this
based on https://lkml.org/lkml/2017/3/16/604. Then everything
could go into the power-supply driver.

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCH 1/2] Add support for OneWire (W1) devices family 0x26 (MAX17211/MAX17215)

[Alex A. Mihaylov]

Hi,


>> Slave device provide software layer for access to internal registers
>> MAX17211/MAX17215 chip.
> Please convert this to regmap.There is no generic w1 handler, but you can provide custom
> read/write functions.
I think regmap be overkill for this driver. Here we need access to a 
small number of registers.  Registers are extremely simple on the 
internal device. As a result, the software layer of regmap will only 
complicate the readability and understanding of the code. And also 
increase the size and time of code execution, and even complicate the 
perception.

> Also it would be nice to have this
> based on https://lkml.org/lkml/2017/3/16/604. Then everything
> could go into the power-supply driver.
>
No problems. Once this set of patches will be accepted in the mainline.

Alex.

Re: [PATCH 1/2] Add support for OneWire (W1) devices family 0x26 (MAX17211/MAX17215)

[Sebastian Reichel]

[-- Attachment #1: Type: text/plain, Size: 822 bytes --]

Hi,

On Sun, Apr 30, 2017 at 08:21:51AM +0300, Alex A. Mihaylov wrote:
> > > Slave device provide software layer for access to internal registers
> > > MAX17211/MAX17215 chip.
> > Please convert this to regmap.There is no generic w1 handler, but you can provide custom
> > read/write functions.
> I think regmap be overkill for this driver. Here we need access to a small
> number of registers.  Registers are extremely simple on the internal device.
> As a result, the software layer of regmap will only complicate the
> readability and understanding of the code. And also increase the size and
> time of code execution, and even complicate the perception.

I did not ask for full usage of all regmap features. Just register
the read/write handler as regmap handler and use regmap_read/write
to get values.

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCH 1/2] Add support for OneWire (W1) devices family 0x26 (MAX17211/MAX17215)

[Alex A. Mihaylov]

Hi!


30.04.17 23:53, Sebastian Reichel wrote::
>>>> Slave device provide software layer for access to internal registers
>>>> MAX17211/MAX17215 chip.
>>> Please convert this to regmap.There is no generic w1 handler, but you can provide custom
>>> read/write functions.
>> I think regmap be overkill for this driver. the perception.
> I did not ask for full usage of all regmap features. Just register
> the read/write handler as regmap handler and use regmap_read/write
> to get values.
>
OK, I think about this. But max17211-battery use ONLY 
w1_max12711x_reg_get(). This is very simple function.

Second function w1_max1721x_reg_set() writen for extend feature list 
(factory calibrating and init battery).  I think, this code must _NOT_ 
be writen, and must _NOT_ be accessible for end user. Change calibration 
values potentially can damage battery or device. Theory, I can unexport 
this function and remove them from drivers code.

So output registers of Maxim M5 Fuel Gauge algorithm very simple: one 
register - one value. In driver I have two points with bitfield. First - 
battery connected from power supply props. Second: very optional device 
type from probe. This value _NOT_ used from driver - just write device 
type, if manufacturer not fill this data in chip nvram.

This moment driver use 14 registers. Ok, let's some time above will be 
14*3=42 registers accessible with w1_max1721x_reg_get(). This value is 
greatly overestimated - so many properties are not in the class 
POWER_SUPPLY. But register range in MAX1721X is 0x1F0 (496 words or 992 
bytes) of RAM for cache registers. As embedded system developer I 
dislike so ram management.

As result I repeat: regmap will be overkill for this driver. But OK, I 
try to write this code. Just for fun.

[PATCH 2/2] Add driver for MAX17211/MAX17215 fuel gauge

[Alex A. Mihaylov]

Maxim Semiconductor MAX17211/MAX17215 single/multi-cell fuel gauge
monitor with M5 Fuel Gauge algorithm

This driver provide userspace access to MAX17211/MAX17215 data with
power_supply class drivers.
---
 drivers/power/supply/Kconfig            |   8 +
 drivers/power/supply/Makefile           |   1 +
 drivers/power/supply/max1721x_battery.c | 303 ++++++++++++++++++++++++++++++++
 3 files changed, 312 insertions(+)
 create mode 100644 drivers/power/supply/max1721x_battery.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 76806a0..25fe441 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -117,6 +117,14 @@ config BATTERY_DS2782
 	  Say Y here to enable support for the DS2782/DS2786 standalone battery
 	  gas-gauge.
 
+config BATTERY_MAX1721X
+	tristate "MAX17211/MAX17215 standalone gas-gauge"
+	depends on W1
+	select W1_SLAVE_MAX1721X
+	help
+	  Say Y here to enable support for the MAX17211/MAX17215 standalone
+	  battery gas-gauge.
+
 config BATTERY_PMU
 	tristate "Apple PMU battery"
 	depends on PPC32 && ADB_PMU
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 36c599d..1e5546d 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_BATTERY_DS2760)	+= ds2760_battery.o
 obj-$(CONFIG_BATTERY_DS2780)	+= ds2780_battery.o
 obj-$(CONFIG_BATTERY_DS2781)	+= ds2781_battery.o
 obj-$(CONFIG_BATTERY_DS2782)	+= ds2782_battery.o
+obj-$(CONFIG_BATTERY_MAX1721X)	+= max1721x_battery.o
 obj-$(CONFIG_BATTERY_GAUGE_LTC2941)	+= ltc2941-battery-gauge.o
 obj-$(CONFIG_BATTERY_GOLDFISH)	+= goldfish_battery.o
 obj-$(CONFIG_BATTERY_PMU)	+= pmu_battery.o
diff --git a/drivers/power/supply/max1721x_battery.c b/drivers/power/supply/max1721x_battery.c
new file mode 100644
index 0000000..ff77d3f
--- /dev/null
+++ b/drivers/power/supply/max1721x_battery.c
@@ -0,0 +1,303 @@
+/*
+ * 1-wire client/driver for the Maxim MAX17211/MAX17215 Fuel Gauge IC
+ *
+ * Author: Alex A. Mihaylov <minimumlaw@rambler.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/param.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/idr.h>
+
+#include "../../w1/w1.h"
+#include "../../w1/slaves/w1_max1721x.h"
+
+#define DEF_DEV_NAME_MAX17211	"MAX17211"
+#define DEF_DEV_NAME_MAX17215	"MAX17215"
+#define DEF_DEV_NAME_UNKNOWN	"UNKNOWN"
+#define DEF_MFG_NAME		"MAXIM"
+
+struct max17211_device_info {
+	struct device *dev;
+	struct power_supply *bat;
+	struct power_supply_desc bat_desc;
+	struct device *w1_dev;
+	/* battery design format */
+	uint16_t rsense; /* in tenths uOhm */
+	char DeviceName[2 * MAX1721X_REG_DEV_NUMB + 1];
+	char ManufacturerName[2 * MAX1721X_REG_MFG_NUMB + 1];
+	char SerialNumber[13]; /* see get_sn_str() later for comment */
+};
+
+static inline struct max17211_device_info *
+to_device_info(struct power_supply *psy)
+{
+	return power_supply_get_drvdata(psy);
+}
+
+static int max1721x_battery_get_property(struct power_supply *psy,
+	enum power_supply_property psp,
+	union power_supply_propval *val)
+{
+	struct max17211_device_info *info = to_device_info(psy);
+	uint16_t reg;
+	int ret = 0;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+		/*
+		 * POWER_SUPPLY_PROP_PRESENT will always readable via
+		 * sysfs interface. Value return 0 if battery not
+		 * present or unaccesable via W1.
+		 */
+		val->intval =
+			w1_max1721x_reg_get(info->w1_dev, MAX172XX_REG_STATUS,
+				&reg) ? 0 : !(reg & MAX172XX_BAT_PRESENT);
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_REPSOC, &reg);
+		val->intval = max172xx_percent_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_BATT, &reg);
+		val->intval = max172xx_voltage_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_DESIGNCAP, &reg);
+		val->intval = max172xx_capacity_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_AVG:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_REPCAP, &reg);
+		val->intval = max172xx_capacity_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_TTE, &reg);
+		val->intval = max172xx_time_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_TTF, &reg);
+		val->intval = max172xx_time_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_TEMP:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_TEMP, &reg);
+		val->intval = max172xx_temperature_to_ps(reg);
+		break;
+	case POWER_SUPPLY_PROP_CURRENT_NOW:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_CURRENT, &reg);
+		val->intval = max172xx_current_to_voltage(reg) / info->rsense;
+		break;
+	case POWER_SUPPLY_PROP_CURRENT_AVG:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX172XX_REG_AVGCURRENT, &reg);
+		val->intval = max172xx_current_to_voltage(reg) / info->rsense;
+		break;
+	/*
+	 * Strings already received and inited by probe.
+	 * We do dummy read for check battery still available.
+	 */
+	case POWER_SUPPLY_PROP_MODEL_NAME:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX1721X_REG_DEV_STR, &reg);
+		val->strval = info->DeviceName;
+		break;
+	case POWER_SUPPLY_PROP_MANUFACTURER:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX1721X_REG_MFG_STR, &reg);
+		val->strval = info->ManufacturerName;
+		break;
+	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
+		ret = w1_max1721x_reg_get(info->w1_dev,
+			MAX1721X_REG_SER_HEX, &reg);
+		val->strval = info->SerialNumber;
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static enum power_supply_property max1721x_battery_props[] = {
+	/* int */
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CHARGE_AVG,
+	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
+	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
+	POWER_SUPPLY_PROP_TEMP,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+	POWER_SUPPLY_PROP_CURRENT_AVG,
+	/* strings */
+	POWER_SUPPLY_PROP_MODEL_NAME,
+	POWER_SUPPLY_PROP_MANUFACTURER,
+	POWER_SUPPLY_PROP_SERIAL_NUMBER,
+};
+
+static int get_string(struct device *dev, uint16_t reg, uint8_t nr, char *str)
+{
+	uint16_t val;
+
+	if (!str || !(reg == MAX1721X_REG_MFG_STR ||
+			reg == MAX1721X_REG_DEV_STR))
+		return -EFAULT;
+
+	while (nr--) {
+		if (w1_max1721x_reg_get(dev, reg++, &val))
+			return -EFAULT;
+		*str++ = val>>8 & 0x00FF;
+		*str++ = val & 0x00FF;
+	}
+	return 0;
+}
+
+/* Maxim say: Serial number is a hex string up to 12 hex characters */
+static int get_sn_string(struct device *dev, char *str)
+{
+	uint16_t val[3];
+
+	if (!str)
+		return -EFAULT;
+
+	if (w1_max1721x_reg_get(dev, MAX1721X_REG_SER_HEX, &val[0]))
+		return -EFAULT;
+	if (w1_max1721x_reg_get(dev, MAX1721X_REG_SER_HEX + 1, &val[1]))
+		return -EFAULT;
+	if (w1_max1721x_reg_get(dev, MAX1721X_REG_SER_HEX + 2, &val[2]))
+		return -EFAULT;
+
+	snprintf(str, 13, "%04X%04X%04X", val[0], val[1], val[2]);
+	return 0;
+}
+
+static int max1721x_battery_probe(struct platform_device *pdev)
+{
+	struct power_supply_config psy_cfg = {};
+	struct max17211_device_info *info;
+
+	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, info);
+
+	info->dev = &pdev->dev;
+	info->w1_dev = pdev->dev.parent;
+	info->bat_desc.name = dev_name(&pdev->dev);
+	info->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+	info->bat_desc.properties = max1721x_battery_props;
+	info->bat_desc.num_properties = ARRAY_SIZE(max1721x_battery_props);
+	info->bat_desc.get_property = max1721x_battery_get_property;
+	/*
+	 * FixMe:
+	 * Device without no_thermal = true not register (err -22)
+	 * Len of platform device name "max17211-battery.X.auto"
+	 * more than 20 chars limit in THERMAL_NAME_LENGTH from
+	 * include/uapi/linux/thermal.h
+	 */
+	info->bat_desc.no_thermal = true;
+	psy_cfg.drv_data = info;
+
+	if (w1_max1721x_reg_get(info->w1_dev,
+			MAX1721X_REG_NRSENSE, &info->rsense))
+		return -ENODEV;
+
+	if (!info->rsense) {
+		dev_warn(info->dev, "RSenese not calibrated, set 10 mOhms!\n");
+		info->rsense = 1000; /* in regs in 10^-5 */
+	}
+	dev_dbg(info->dev, "RSense: %d mOhms.\n", info->rsense / 100);
+
+	if (get_string(info->w1_dev, MAX1721X_REG_MFG_STR,
+			MAX1721X_REG_MFG_NUMB, info->ManufacturerName)) {
+		dev_err(info->dev, "Can't read manufacturer. Hardware error.\n");
+		return -ENODEV;
+	}
+
+	if (!info->ManufacturerName[0])
+		strncpy(info->ManufacturerName, DEF_MFG_NAME,
+			2 * MAX1721X_REG_MFG_NUMB);
+
+	if (get_string(info->w1_dev, MAX1721X_REG_DEV_STR,
+			MAX1721X_REG_DEV_NUMB, info->DeviceName)) {
+		dev_err(info->dev, "Can't read device. Hardware error.\n");
+		return -ENODEV;
+	}
+	if (!info->DeviceName[0]) {
+		uint16_t dev_name;
+
+		if (w1_max1721x_reg_get(info->w1_dev,
+				MAX172XX_REG_DEVNAME, &dev_name)) {
+			dev_err(info->w1_dev, "Can't read device name reg.\n");
+			return -ENODEV;
+		}
+
+		switch (dev_name & MAX172XX_DEV_MASK) {
+		case MAX172X1_DEV:
+			strncpy(info->DeviceName, DEF_DEV_NAME_MAX17211,
+				2 * MAX1721X_REG_DEV_NUMB);
+			break;
+		case MAX172X5_DEV:
+			strncpy(info->DeviceName, DEF_DEV_NAME_MAX17215,
+				2 * MAX1721X_REG_DEV_NUMB);
+			break;
+		default:
+			strncpy(info->DeviceName, DEF_DEV_NAME_UNKNOWN,
+				2 * MAX1721X_REG_DEV_NUMB);
+		}
+	}
+
+	if (get_sn_string(info->w1_dev, info->SerialNumber)) {
+		dev_err(info->dev, "Can't read serial. Hardware error.\n");
+		return -ENODEV;
+	}
+
+	info->bat = power_supply_register(&pdev->dev, &info->bat_desc,
+						&psy_cfg);
+	if (IS_ERR(info->bat)) {
+		dev_err(info->dev, "failed to register battery\n");
+		return PTR_ERR(info->bat);
+	}
+
+	return 0;
+}
+
+static int max1721x_battery_remove(struct platform_device *pdev)
+{
+	struct max17211_device_info *info = platform_get_drvdata(pdev);
+
+	power_supply_unregister(info->bat);
+
+	return 0;
+}
+
+static struct platform_driver max1721x_battery_driver = {
+	.driver = {
+		.name = "max1721x-battery",
+	},
+	.probe	  = max1721x_battery_probe,
+	.remove   = max1721x_battery_remove,
+};
+module_platform_driver(max1721x_battery_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alex A. Mihaylov <minimumlaw@rambler.ru>");
+MODULE_DESCRIPTION("Maxim MAX17211/MAX17215 Fuel Gauage IC driver");
+MODULE_ALIAS("platform:max1721x-battery");
-- 
2.8.4 (Apple Git-73)

Re: [PATCH 2/2] Add driver for MAX17211/MAX17215 fuel gauge

[Sebastian Reichel]

[-- Attachment #1: Type: text/plain, Size: 3927 bytes --]

Hi,

Please make sure you Cc the relevant people / mailing lists. You
can use ./scripts/get_maintainer.pl to find out who should receive
the patches.

On Sat, Apr 29, 2017 at 05:34:29PM +0300, Alex A. Mihaylov wrote:
> Maxim Semiconductor MAX17211/MAX17215 single/multi-cell fuel gauge
> monitor with M5 Fuel Gauge algorithm
> 
> This driver provide userspace access to MAX17211/MAX17215 data with
> power_supply class drivers.

> ---
>  drivers/power/supply/Kconfig            |   8 +
>  drivers/power/supply/Makefile           |   1 +

Please move the entries in both files before CONFIG_BATTERY_MAX17040.

> [...]
>
> +	 * FixMe:
> +	 * Device without no_thermal = true not register (err -22)
> +	 * Len of platform device name "max17211-battery.X.auto"
> +	 * more than 20 chars limit in THERMAL_NAME_LENGTH from
> +	 * include/uapi/linux/thermal.h
> +	 */

IIRC we already had problems with small THERMAL_NAME_LENGTH before.
I suggest to add another patch, that increases THERMAL_NAME_LENGTH
(don't forget to Cc/To the thermal subsystem people).

> +	info->bat_desc.no_thermal = true;
> +	psy_cfg.drv_data = info;
> +
> +	if (w1_max1721x_reg_get(info->w1_dev,
> +			MAX1721X_REG_NRSENSE, &info->rsense))
> +		return -ENODEV;
> +
> +	if (!info->rsense) {
> +		dev_warn(info->dev, "RSenese not calibrated, set 10 mOhms!\n");
> +		info->rsense = 1000; /* in regs in 10^-5 */
> +	}
> +	dev_dbg(info->dev, "RSense: %d mOhms.\n", info->rsense / 100);
> +
> +	if (get_string(info->w1_dev, MAX1721X_REG_MFG_STR,
> +			MAX1721X_REG_MFG_NUMB, info->ManufacturerName)) {
> +		dev_err(info->dev, "Can't read manufacturer. Hardware error.\n");
> +		return -ENODEV;
> +	}
> +
> +	if (!info->ManufacturerName[0])
> +		strncpy(info->ManufacturerName, DEF_MFG_NAME,
> +			2 * MAX1721X_REG_MFG_NUMB);
> +
> +	if (get_string(info->w1_dev, MAX1721X_REG_DEV_STR,
> +			MAX1721X_REG_DEV_NUMB, info->DeviceName)) {
> +		dev_err(info->dev, "Can't read device. Hardware error.\n");
> +		return -ENODEV;
> +	}
> +	if (!info->DeviceName[0]) {
> +		uint16_t dev_name;
> +
> +		if (w1_max1721x_reg_get(info->w1_dev,
> +				MAX172XX_REG_DEVNAME, &dev_name)) {
> +			dev_err(info->w1_dev, "Can't read device name reg.\n");
> +			return -ENODEV;
> +		}
> +
> +		switch (dev_name & MAX172XX_DEV_MASK) {
> +		case MAX172X1_DEV:
> +			strncpy(info->DeviceName, DEF_DEV_NAME_MAX17211,
> +				2 * MAX1721X_REG_DEV_NUMB);
> +			break;
> +		case MAX172X5_DEV:
> +			strncpy(info->DeviceName, DEF_DEV_NAME_MAX17215,
> +				2 * MAX1721X_REG_DEV_NUMB);
> +			break;
> +		default:
> +			strncpy(info->DeviceName, DEF_DEV_NAME_UNKNOWN,
> +				2 * MAX1721X_REG_DEV_NUMB);
> +		}
> +	}
> +
> +	if (get_sn_string(info->w1_dev, info->SerialNumber)) {
> +		dev_err(info->dev, "Can't read serial. Hardware error.\n");
> +		return -ENODEV;
> +	}
> +
> +	info->bat = power_supply_register(&pdev->dev, &info->bat_desc,
> +						&psy_cfg);
> +	if (IS_ERR(info->bat)) {
> +		dev_err(info->dev, "failed to register battery\n");
> +		return PTR_ERR(info->bat);
> +	}

Please use devm_power_supply_register() and drop the remove
function.

> +	return 0;
> +}
> +
> +static int max1721x_battery_remove(struct platform_device *pdev)
> +{
> +	struct max17211_device_info *info = platform_get_drvdata(pdev);
> +
> +	power_supply_unregister(info->bat);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver max1721x_battery_driver = {
> +	.driver = {
> +		.name = "max1721x-battery",
> +	},
> +	.probe	  = max1721x_battery_probe,
> +	.remove   = max1721x_battery_remove,
> +};
> +module_platform_driver(max1721x_battery_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Alex A. Mihaylov <minimumlaw@rambler.ru>");
> +MODULE_DESCRIPTION("Maxim MAX17211/MAX17215 Fuel Gauage IC driver");
> +MODULE_ALIAS("platform:max1721x-battery");

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCH 2/2] Add driver for MAX17211/MAX17215 fuel gauge

[Михайлов Алексей Анатольевич]

Hi!


>> [...]
>>
>> +	 * FixMe:
>> +	 * Device without no_thermal = true not register (err -22)
>> +	 * Len of platform device name "max17211-battery.X.auto"
>> +	 * more than 20 chars limit in THERMAL_NAME_LENGTH from
>> +	 * include/uapi/linux/thermal.h
>> +	 */
> IIRC we already had problems with small THERMAL_NAME_LENGTH before.
> I suggest to add another patch, that increases THERMAL_NAME_LENGTH
> (don't forget to Cc/To the thermal subsystem people).
May be rename "max17211-battery" to "max17211" and remove no_thermal = 
true? This case thermal zone will work again. In current (mainline) 
kernel all drivers "xxxxxx-battery" (like ds2780-battery or 
ds2760-battery) compiled, but not working (not registered). They can 
start working again without thermal zone by adding no_thermal = true or 
by remove "-battery" from platform device name. Alternative limit on 
THERMAL_NAME_LENGTH may be extended.
>> +	info->bat = power_supply_register(&pdev->dev, &info->bat_desc,
>> +						&psy_cfg);
>> +	if (IS_ERR(info->bat)) {
>> +		dev_err(info->dev, "failed to register battery\n");
>> +		return PTR_ERR(info->bat);
>> +	}
> Please use devm_power_supply_register() and drop the remove
> function.
Khm... probe/remove paired functions. I can use 
devm_power_supply_register in my code. But all other fuel gauge drivers 
use classic probe/remove pair. Which decision will be more correct?

Re: [PATCH 2/2] Add driver for MAX17211/MAX17215 fuel gauge

[Sebastian Reichel]

[-- Attachment #1: Type: text/plain, Size: 2054 bytes --]

Hi,

On Sun, Apr 30, 2017 at 08:32:10PM +0300, Михайлов Алексей Анатольевич wrote:
> > IIRC we already had problems with small THERMAL_NAME_LENGTH before.
> > I suggest to add another patch, that increases THERMAL_NAME_LENGTH
> > (don't forget to Cc/To the thermal subsystem people).
> May be rename "max17211-battery" to "max17211" and remove no_thermal = true?
> This case thermal zone will work again. In current (mainline) kernel all
> drivers "xxxxxx-battery" (like ds2780-battery or ds2760-battery) compiled,
> but not working (not registered). They can start working again without
> thermal zone by adding no_thermal = true or by remove "-battery" from
> platform device name. Alternative limit on THERMAL_NAME_LENGTH may be
> extended.

I think increasing THERMAL_NAME_LENGTH is the right way.

> > > +	info->bat = power_supply_register(&pdev->dev, &info->bat_desc,
> > > +						&psy_cfg);
> > > +	if (IS_ERR(info->bat)) {
> > > +		dev_err(info->dev, "failed to register battery\n");
> > > +		return PTR_ERR(info->bat);
> > > +	}
> > Please use devm_power_supply_register() and drop the remove
> > function.
> Khm... probe/remove paired functions. I can use devm_power_supply_register
> in my code. But all other fuel gauge drivers use classic probe/remove pair.
> Which decision will be more correct?

Most drivers are older than devm_power_supply_register. We already
have a few fuel gauge drivers, which use it, though:

$ git grep devm_power_supply_register | grep "battery" 
88pm860x_battery.c:	info->battery = devm_power_supply_register(&pdev->dev,
da9150-fg.c:	fg->battery = devm_power_supply_register(dev, &fg_desc, NULL);
max17042_battery.c:	chip->battery = devm_power_supply_register(&client->dev, max17042_desc,
max8997_charger.c:	charger->battery = devm_power_supply_register(&pdev->dev,
max8998_charger.c:	max8998->battery = devm_power_supply_register(max8998->dev,
sbs-battery.c:	chip->power_supply = devm_power_supply_register(&client->dev, sbs_desc,

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]