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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170429164053.olynja4kyqpwhfpk@earth>
Date:   Sat, 29 Apr 2017 18:40:53 +0200
From:   Sebastian Reichel <sre@...nel.org>
To:     "Alex A. Mihaylov" <minimumlaw@...bler.ru>
Cc:     linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        zbr@...emap.net
Subject: Re: [PATCH 2/2] Add driver for MAX17211/MAX17215 fuel gauge

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@...bler.ru>");
> +MODULE_DESCRIPTION("Maxim MAX17211/MAX17215 Fuel Gauage IC driver");
> +MODULE_ALIAS("platform:max1721x-battery");

-- Sebastian

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)