linux-kernel - Re: [PATCH 2/3] power: supply: cpcap-battery: Fix battery identification

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Message-ID: <20221110160559.bsvzr4txum5ed2qz@mercury.elektranox.org>
Date:   Thu, 10 Nov 2022 17:05:59 +0100
From:   Sebastian Reichel <sebastian.reichel@...labora.com>
To:     Ivaylo Dimitrov <ivo.g.dimitrov.75@...il.com>
Cc:     linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
        tony@...mide.com, philipp@...s.xyz
Subject: Re: [PATCH 2/3] power: supply: cpcap-battery: Fix battery
 identification

Hi,

On Sat, Nov 05, 2022 at 01:25:43PM +0200, Ivaylo Dimitrov wrote:
> Use the same logic to identify genuine batteries as Android does.
> 
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@...il.com>
> ---

Why do we care?

-- Sebastian

>  drivers/power/supply/cpcap-battery.c | 19 ++++++++++++++-----
>  1 file changed, 14 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
> index 8869067..ca6ee2b 100644
> --- a/drivers/power/supply/cpcap-battery.c
> +++ b/drivers/power/supply/cpcap-battery.c
> @@ -422,7 +422,7 @@ static int cpcap_battery_cc_to_ua(struct cpcap_battery_ddata *ddata,
>  
>  static int cpcap_battery_match_nvmem(struct device *dev, const void *data)
>  {
> -	if (strcmp(dev_name(dev), "89-500029ba0f73") == 0)
> +	if (strncmp(dev_name(dev), "89-500", 6) == 0)
>  		return 1;
>  	else
>  		return 0;
> @@ -439,10 +439,19 @@ static void cpcap_battery_detect_battery_type(struct cpcap_battery_ddata *ddata)
>  	if (IS_ERR_OR_NULL(nvmem)) {
>  		ddata->check_nvmem = true;
>  		dev_info_once(ddata->dev, "Can not find battery nvmem device. Assuming generic lipo battery\n");
> -	} else if (nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) {
> -		battery_id = 0;
> -		ddata->check_nvmem = true;
> -		dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n");
> +	} else {
> +		char buf[24];
> +
> +		if (nvmem_device_read(nvmem, 96, 4, buf) < 0 ||
> +		    strncmp(buf, "COPR", 4) != 0 ||
> +		    nvmem_device_read(nvmem, 104, 24, buf) < 0 ||
> +		    strncmp(buf, "MOTOROLA E.P CHARGE ONLY", 24) != 0 ||
> +		    nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) {
> +			battery_id = 0;
> +			ddata->check_nvmem = true;
> +			dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n");
> +		}
> +
>  	}
>  
>  	switch (battery_id) {
> -- 
> 1.9.1
> 

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