Re: Fwd: [PATCH] bq27x00_battery: Add new properties

[Rodolfo Giometti <giometti@enneenne.com>]

On Mon, Jan 31, 2011 at 04:51:47PM +0300, Anton Vorontsov wrote:
> Forwarding this to lkml and bq27x00 hackers.
> 
> Comments, Reviewed-by or Acked-by?
> 
> ----- Forwarded message from Pali Rohár <pali.rohar@gmail.com> -----
> 
> Date: Wed, 26 Jan 2011 21:44:08 +0100
> From: Pali Rohár <pali.rohar@gmail.com>
> To: Anton Vorontsov <cbouatmailru@gmail.com>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Subject: Re: [PATCH] bq27x00_battery
> 
> This patch add support for properties POWER_SUPPLY_PROP_CHARGE_NOW,
> POWER_SUPPLY_PROP_CHARGE_FULL, POWER_SUPPLY_PROP_ENERGY_NOW,
> POWER_SUPPLY_PROP_ONLINE in module bq27x00_battery.
> 
> Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
> Tested-by: Pali Rohár <pali.rohar@gmail.com>
> 
> --- a/drivers/power/bq27x00_battery.c	2011-01-26 21:32:34.000000000 +0100
> +++ b/drivers/power/bq27x00_battery.c	2011-01-26 21:23:26.000000000 +0100
> @@ -3,9 +3,14 @@
>   *
>   * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
>   * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
> + * Copyright (C) 2011 Pali Rohár <pali.rohar@gmail.com>

I think you should put your copyright on the changes you did:
i.e. GPIO settings and so on. Example:

    * GPIO setting/management and ... by Pali Rohár <pali.rohar@gmail.com>
    *         Copyright (C) 2011

>   *
>   * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
>   *
> + * Datasheets:
> + * http://focus.ti.com/docs/prod/folders/print/bq27000.html
> + * http://focus.ti.com/docs/prod/folders/print/bq27500.html
> + *

Don't mix copyright messages with info ones. Put these info at the end
of this into text.

>   * This package 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.
> @@ -27,8 +32,9 @@
>  #include <linux/slab.h>
>  #include <asm/unaligned.h>
> 
> -#define DRIVER_VERSION			"1.1.0"
> +#define DRIVER_VERSION			"1.2.0"
> 
> +#define BQ27x00_REG_MODE		0x00
>  #define BQ27x00_REG_TEMP		0x06
>  #define BQ27x00_REG_VOLT		0x08
>  #define BQ27x00_REG_AI			0x14
> @@ -36,10 +42,14 @@
>  #define BQ27x00_REG_TTE			0x16
>  #define BQ27x00_REG_TTF			0x18
>  #define BQ27x00_REG_TTECP		0x26
> +#define BQ27x00_REG_NAC			0x0C /* Nominal available capaciy */
> +#define BQ27x00_REG_LMD			0x12 /* Last measured discharge */
> +#define BQ27x00_REG_AE			0x22 /* Available Enery */
> 
>  #define BQ27000_RS			20 /* Resistor sense */
>  #define BQ27000_REG_RSOC		0x0B /* Relative State-of-Charge */
>  #define BQ27000_FLAG_CHGS		BIT(7)
> +#define BQ27000_FLAG_FC			BIT(5)
> 
>  #define BQ27500_REG_SOC			0x2C
>  #define BQ27500_FLAG_DSC		BIT(0)
> @@ -75,7 +85,11 @@ static enum power_supply_property bq27x0
>  	POWER_SUPPLY_PROP_VOLTAGE_NOW,
>  	POWER_SUPPLY_PROP_CURRENT_NOW,
>  	POWER_SUPPLY_PROP_CAPACITY,
> +	POWER_SUPPLY_PROP_CHARGE_NOW,
> +	POWER_SUPPLY_PROP_CHARGE_FULL,
> +	POWER_SUPPLY_PROP_ENERGY_NOW,
>  	POWER_SUPPLY_PROP_TEMP,
> +	POWER_SUPPLY_PROP_ONLINE,
>  	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
>  	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
>  	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
> @@ -92,6 +106,24 @@ static int bq27x00_read(u8 reg, int *rt_
>  }
> 
>  /*
> + * Return the GPIO status (0 or 1)
> + * Or < 0 if something fails.
> + */
> +static int bq27x00_battery_gpio(struct bq27x00_device_info *di)
> +{
> +	int ret;
> +	int gpio = 0;
> +
> +	ret = bq27x00_read(BQ27x00_REG_MODE, &gpio, 0, di);
> +	if (ret) {

I think you should use ret < 0.

> +		dev_err(di->dev, "error reading GPIO status\n");
> +		return ret;
> +	}
> +
> +	return (gpio & 0x40) >> 6;

Why not using:

   !!(gpio & 0x40)

or

   (gpio & 0x40) ? 1 : 0

? I think it could be more readable... :)

However, I don't understand why you fix gpio=0... it's your machine
depending settings? In these case you should use the platform_data
mechanism to properly setup the GPIO.

> +}
> +
> +/*
>   * Return the battery temperature in tenths of degree Celsius
>   * Or < 0 if something fails.
>   */
> @@ -188,6 +220,75 @@ static int bq27x00_battery_rsoc(struct b
>  	return rsoc;
>  }
> 
> +/*
> + * Return the battery Nominal available capaciy in µAh
> + * Or < 0 if something fails.
> + */
> +static int bq27x00_battery_nac(struct bq27x00_device_info *di)

Let me suggest using bq27x00_battery_nac_uAh as function name...

> +{
> +	int ret;
> +	int nac = 0;
> +
> +	ret = bq27x00_read(BQ27x00_REG_NAC, &nac, 0, di);
> +	if (ret) {

Ditto.

> +		dev_err(di->dev, "error reading nominal available capaciy\n");
> +		return ret;
> +	}
> +
> +	if (di->chip == BQ27500)
> +		nac *= 1000;
> +	else
> +		nac = nac * 3570 / BQ27000_RS;
> +
> +	return nac;
> +}
> +
> +/*
> + * Return the battery Last measured discharge in µAh
> + * Or < 0 if something fails.
> + */
> +static int bq27x00_battery_lmd(struct bq27x00_device_info *di)

bq27x00_battery_lmd_uAh

> +{
> +	int ret;
> +	int lmd = 0;
> +
> +	ret = bq27x00_read(BQ27x00_REG_LMD, &lmd, 0, di);
> +	if (ret) {

Ditto.

> +		dev_err(di->dev, "error reading last measured discharge\n");
> +		return ret;
> +	}
> +
> +	if (di->chip == BQ27500)
> +		lmd *= 1000;
> +	else
> +		lmd = lmd * 3570 / BQ27000_RS;
> +
> +	return lmd;
> +}
> +
> +/*
> + * Return the battery Available energy in µWh
> + * Or < 0 if something fails.
> + */
> +static int bq27x00_battery_energy(struct bq27x00_device_info *di)

bq27x00_battery_energy_uWh

> +{
> +	int ret;
> +	int ae = 0;
> +
> +	ret = bq27x00_read(BQ27x00_REG_LMD, &ae, 0, di);
> +	if (ret) {

Ditto.

> +		dev_err(di->dev, "error reading available energy\n");
> +		return ret;
> +	}
> +
> +	if (di->chip == BQ27500)
> +		ae *= 1000;
> +	else
> +		ae = ae * 29200 / BQ27000_RS;
> +
> +	return ae;
> +}
> +
>  static int bq27x00_battery_status(struct bq27x00_device_info *di,
>  				  union power_supply_propval *val)
>  {
> @@ -209,7 +310,9 @@ static int bq27x00_battery_status(struct
>  		else
>  			status = POWER_SUPPLY_STATUS_CHARGING;
>  	} else {
> -		if (flags & BQ27000_FLAG_CHGS)
> +		if (flags & BQ27000_FLAG_FC)
> +			status = POWER_SUPPLY_STATUS_FULL;
> +		else if (flags & BQ27000_FLAG_CHGS)
>  			status = POWER_SUPPLY_STATUS_CHARGING;
>  		else
>  			status = POWER_SUPPLY_STATUS_DISCHARGING;
> @@ -256,6 +359,9 @@ static int bq27x00_battery_get_property(
>  	case POWER_SUPPLY_PROP_STATUS:
>  		ret = bq27x00_battery_status(di, val);
>  		break;
> +	case POWER_SUPPLY_PROP_ONLINE:
> +		val->intval = bq27x00_battery_gpio(di);
> +		break;
>  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
>  	case POWER_SUPPLY_PROP_PRESENT:
>  		val->intval = bq27x00_battery_voltage(di);
> @@ -268,6 +374,15 @@ static int bq27x00_battery_get_property(
>  	case POWER_SUPPLY_PROP_CAPACITY:
>  		val->intval = bq27x00_battery_rsoc(di);
>  		break;
> +	case POWER_SUPPLY_PROP_CHARGE_NOW:
> +		val->intval = bq27x00_battery_nac(di);
> +		break;
> +	case POWER_SUPPLY_PROP_CHARGE_FULL:
> +		val->intval = bq27x00_battery_lmd(di);
> +		break;
> +	case POWER_SUPPLY_PROP_ENERGY_NOW:
> +		val->intval = bq27x00_battery_energy(di);
> +		break;
>  	case POWER_SUPPLY_PROP_TEMP:
>  		val->intval = bq27x00_battery_temperature(di);
>  		break;
> @@ -472,4 +587,7 @@ module_exit(bq27x00_battery_exit);
> 
>  MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
>  MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
> +MODULE_ALIAS("i2c:bq27000");
> +MODULE_ALIAS("i2c:bq27200");
> +MODULE_ALIAS("i2c:bq27500");
>  MODULE_LICENSE("GPL");
> 
> ----- End forwarded message -----

-- 

GNU/Linux Solutions                  e-mail: giometti@enneenne.com
Linux Device Driver                          giometti@linux.it
Embedded Systems                     phone:  +39 349 2432127
UNIX programming                     skype:  rodolfo.giometti
Freelance ICT Italia - Consulente ICT Italia - www.consulenti-ict.it