[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20140110105621.GC6798@e106331-lin.cambridge.arm.com>
Date: Fri, 10 Jan 2014 10:56:21 +0000
From: Mark Rutland <mark.rutland@....com>
To: Vladimir Barinov <vladimir.barinov@...entembedded.com>
Cc: "anton@...msg.org" <anton@...msg.org>,
"dwmw2@...radead.org" <dwmw2@...radead.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
"mk7.kang@...sung.com" <mk7.kang@...sung.com>
Subject: Re: [PATCH 2/3] dt: Document ModelGauge gauge bindings
On Thu, Jan 09, 2014 at 04:49:04PM +0000, Vladimir Barinov wrote:
> These bindings can be used to register Maxim ModelGauge ICs fuel gauge
> (MAX17040/41/43/44/48/49/58/59)
>
> Signed-off-by: Vladimir Barinov <vladimir.barinov@...entembedded.com>
>
> ---
> Documentation/devicetree/bindings/power_supply/modelgauge_battery.txt | 82 ++++++++++
> 1 file changed, 82 insertions(+)
>
> Index: battery-2.6/Documentation/devicetree/bindings/power_supply/modelgauge_battery.txt
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ battery-2.6/Documentation/devicetree/bindings/power_supply/modelgauge_battery.txt 2014-01-09 15:09:38.035138887 +0400
> @@ -0,0 +1,82 @@
> +modelgauge_battery
> +~~~~~~~~~~~~~~~~~~
> +
> +Required properties:
> + - compatible : should contain one of the following:
> + - "maxim,max17040" for MAX17040
> + - "maxim,max17041" for MAX17041
> + - "maxim,max17043" for MAX17043
> + - "maxim,max17044" for MAX17044
> + - "maxim,max17048" for MAX17048
> + - "maxim,max17049" for MAX17049
> + - "maxim,max17058" for MAX17058
> + - "maxim,max17059" for MAX17059
> +
> +Optional properties:
> + - maxim,empty_alert_threshold : Capacity threshold where an interrupt is
> + generated on the ALRT pin;
s/_/-/ in proeprty names please.
Why is this property in the dt at all?
Surely the driver can choose the value it wants.
The driver can choose a sensible value, surely?
> +
> + - soc_change_alert : /* alert for 1% soc change */
Likewise, surely the driver should decide if it wants this?
> + - hibernate_threshold : Hibernate threshold (crate), where IC
> + enters hibernate mode
> + - active_threshold : Active threshold (mV), where IC exits
> + hibernate mode
> + - undervoltage : Voltage (mV), when IC alerts while battery
> + voltage less then undervoltage
> + - overvoltage : Voltage (mV), when IC alerts while battery
> + voltage greater then overvoltage
> + - maxim,resetvoltage : Voltage threshold (mV) below which the IC
> + resets itself. Used to detect battery removal
> + and reinsertion;
Could you elaborate on what these are for. How variable are these
between batteries?
> + - maxim,empty_adjustment : Capacity charge empty design value;
> + - maxim,full_adjustment : Capacity charge full design value;
These names are a bit odd.
How about maxim,charge-empty and maxim,charge-full (perhaps
maxim,charge-empty-design).
> + - maxim,rcomp0 : ModelGauge RCOMP parameter, used for
> + temperature compensation;
> + - maxim,temp_co_up : ModelGauge TempCoUp parameter, used for
> + temperature compensation;
> + - maxim,temp_co_down : ModelGauge TempCoDown parameter, used for
> + temperature compensation;
> + - maxim,ocvtest : ModelGauge OCVTest parameter, used for
> + verification of Custom Model calibration data
> + loaded into IC RAM;
> + - maxim,soc_check_a : ModelGauge SOCCheckA parameter, used for
> + verification of Custom Model calibration data
> + loaded into IC RAM;
> + - maxim,soc_check_b : ModelGauge SOCCheckB parameter, used for
> + verification of Custom Model calibration data
> + loaded into IC RAM;
> + - maxim,bits : ModelGauge Bits parameter, used as
> + scaling parameter in Custom Model algorithm;
> + - maxim,model_data : ModelGauge ModelData data,
> + Custom Model calibration data.
I have no idea what these properties mean, so I can't comment on them as
they are other than to say this looks a bit low-level. Are there any
docs?
> +
> +Example:
> +
> +modelgauge@36 {
> + compatible = "maxim,max17058";
> + reg = <0x36>;
> + interrupt-parent = <&msmgpio>;
> + interrupts = <107 0x2>;
This portion of the example looks fine.
> +
> + maxim,empty_alert_threshold = /bits/ 8 <15>;
> + maxim,resetvoltage = /bits/ 16 <0>;
> + maxim,empty_adjustment = /bits/ 8 <0>;
> + maxim,full_adjustment = /bits/ 8 <100>;
> + maxim,rcomp0 = /bits/ 8 <175>;
You did not describe that any of these were 8-bit values in the binding.
> + maxim,temp_co_up = <(-1100)>;
> + maxim,temp_co_down = <(-4000)>;
These weren't described as signed.
> + maxim,ocvtest = /bits/ 16 <56144>;
> + maxim,soc_check_a = /bits/ 8 <241>;
> + maxim,soc_check_b = /bits/ 8 <243>;
> + maxim,bits = /bits/ 8 <19>;
These weren't described as 8-bit either.
> +
> + maxim,model_data = /bits/ 8 <
> + 0x9B 0x70 0xAB 0x30 0xB5 0xA0 0xB9 0xD0
> + 0xBB 0xA0 0xBC 0x00 0xBC 0xB0 0xBD 0x00
> + 0xBD 0x60 0xBE 0x40 0xBF 0x40 0xC1 0xF0
> + 0xC5 0x60 0xC8 0xA0 0xCD 0x00 0xD1 0x50
> + 0x00 0xE0 0x01 0x80 0x18 0x60 0x1C 0x20
> + 0x54 0x00 0x6A 0xC0 0x79 0x20 0x65 0xC0
> + 0x0B 0xE0 0x2A 0xC0 0x1D 0x00 0x17 0xE0
> + 0x15 0xE0 0x11 0xE0 0x11 0x00 0x11 0x00>;
> +};
This looks scary.
Thanks,
Mark.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists