linux-kernel - Re: [PATCH v8 2/2] mfd: max597x: Add support for MAX5970 and MAX5978

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 for Android: free password hash cracker in your pocket

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

Message-ID: <6f2880d6-04e6-867a-f61b-30a65554e280@9elements.com>
Date:   Mon, 14 Nov 2022 23:50:15 +0530
From:   Naresh Solanki <naresh.solanki@...ements.com>
To:     Lee Jones <lee@...nel.org>
Cc:     linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
        Patrick Rudolph <patrick.rudolph@...ements.com>,
        Marcello Sylvester Bauer <sylv@...v.io>
Subject: Re: [PATCH v8 2/2] mfd: max597x: Add support for MAX5970 and MAX5978

Hi Lee,

On 14-11-2022 02:41 pm, Lee Jones wrote:
> On Fri, 11 Nov 2022, Naresh Solanki wrote:
>> On 07-11-2022 03:06 pm, Lee Jones wrote:
>>> On Thu, 03 Nov 2022, Naresh Solanki wrote:
>>>
>>>> From: Patrick Rudolph <patrick.rudolph@...ements.com>
>>>>
>>>> Implement a regulator driver with IRQ support for fault management.
>>>
>>> This is not a "regulator driver".
>>>
>>>> Written against documentation [1] and [2] and tested on real hardware.
>>>>
>>>> Every channel has its own regulator supplies nammed 'vss1-supply' and
>>>> 'vss2-supply'. The regulator supply is used to determine the output
>>>> voltage, as the smart switch provides no output regulation.
>>>> The driver requires the 'shunt-resistor-micro-ohms' property to be
>>>> present in Device Tree to properly calculate current related
>>>> values.
>>>>
>>>> Datasheet links:
>>>> 1: https://datasheets.maximintegrated.com/en/ds/MAX5970.pdf
>>>> 2: https://datasheets.maximintegrated.com/en/ds/MAX5978.pdf
>>>>
>>>> Signed-off-by: Patrick Rudolph <patrick.rudolph@...ements.com>
>>>> Signed-off-by: Marcello Sylvester Bauer <sylv@...v.io>
>>>> Signed-off-by: Naresh Solanki <Naresh.Solanki@...ements.com>
> 
> [...]
> 
Patrick & Marcello worked on the patch. I'm upstreaming it. Will update 
it as:
Signed-off-by: Patrick Rudolph <patrick.rudolph@...ements.com>
Co-Developed-by: Marcello Sylvester Bauer <sylv@...v.io>
Signed-off-by: Naresh Solanki <Naresh.Solanki@...ements.com>

ok?

>>>> +static const struct of_device_id max597x_of_match[] = {
>>>> +	{ .compatible = "maxim,max5970", .data = (void *)MAX597x_TYPE_MAX5970 },
>>>> +	{ .compatible = "maxim,max5978", .data = (void *)MAX597x_TYPE_MAX5978 },
>>>
>>> Where is .data used?
>> The .data isn't used.
> 
> Then why add it?
Yes. Will remove that in next version.
> 
> [...]
> 
>>>> +#include <linux/device.h>
>>>> +#include <linux/regmap.h>
>>>> +
>>>> +/* Number of switch based on chip variant */
>>>
>>> This comment is superfluous.
>> You mean this comment should be removed ?
> 
> I do.
Sure will remove.
> 
>>>> +#define MAX5970_NUM_SWITCHES 2
>>>> +#define MAX5978_NUM_SWITCHES 1
>>>> +/* Both chip variant have 4 indication LEDs used by LED cell */
>>>
>>> Here too I think.
>>>
>>>> +#define MAX597X_NUM_LEDS     4
>>>> +
>>>> +enum max597x_chip_type {
>>>> +	MAX597x_TYPE_MAX5978 = 1,
>>>
>>> Why 1?
>> MAX5978 & single power switch wheres MAX5970 has two.
> 
> That's not what this enum means.
> 
> You are just describing the type to be matched on.
> 
> The value should be arbitrary, no?
Yes you are right. And thats how its being used.
Setting the first enum value to 1 was to avoid zero.
> 
> [...]
> 
>>>> +#define  OC_STATUS_WARN(ch)				BIT(ch)
>>>> +
>>>> +#define MAX5970_REG_CHXEN				0x3b
>>>> +#define  CHXEN(ch)						(3 << (ch * 2))
>>>> +
>>>> +#define MAX5970_REG_LED_FLASH			0x43
>>>
>>> Do these all need to be shared?
>>>
>>> Or can they be isolated into, say, the Regulator driver?
>>>
>> Shared reg.
> 
> Where else are they used?
> 
The respective cell regulator/iio & led driver.

Regards,
Naresh