Re: Linux driver for IRPS5401 - status reg not found

[Robert Hancock <hancock@sedsystems.ca>]

On 2020-03-30 12:48 p.m., Guenter Roeck wrote:
> On 3/30/20 8:42 AM, Robert Hancock wrote:
>> On 2020-03-30 9:24 a.m., Guenter Roeck wrote:
>>> On 3/30/20 4:33 AM, Michal Simek wrote:
>>>> Hi Robert and Guenter,
>>>>
>>>> Xilinx boards are using IRPS5401 chips and I have tried to use your driver.
>>>> I have checked that u-boot can detect that devices and read it.
>>>>
>>>> ZynqMP> i2c probe
>>>> Valid chip addresses: 0C 13 14 20 43 44 74
>>>> ZynqMP> i2c md 13 0 10
>>>> 0000: 00 08 00 08 00 08 00 08 00 08 00 08 00 08 00 08    ................
>>>> ZynqMP> i2c md 14 0 10
>>>> 0000: 00 08 00 08 00 08 00 08 00 08 00 08 00 08 00 08    ................
>>>> ZynqMP> i2c md 43 0 10
>>>> 0000: 00 98 ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
>>>> ZynqMP> i2c md 44 0 10
>>>> 0000: 00 8a ff ff ff ff ff ff ff ff ff ff ff ff ff ff    ................
>>>> ZynqMP>
>>>>
>>>> Here is DT fragment which I use (it is under i2c mux)
>>>>
>>>> 185                         irps5401_43: irps5401@43 {
>>>> 186                                 compatible = "infineon,irps5401";
>>>> 187                                 reg = <0x43>; /* pmbus / i2c 0x13 */
>>>
>>> Does that mean the mux is at 0x13 ?
>>
>> These chips have two I2C addresses with two separate interfaces: the standard PMBus-compatible interface at an address between 0x40-0x4f, which the irps5401 driver supports, and another proprietary interface at an address between 0x10-0x1f. The specific addresses in those ranges is configured by the value of a resistor on one of the pins.
>>
> 
> Ah, sorry, I didn't get that part earlier. Unfortunately, the datasheet
> doesn't seem to include a description of the proprietary interface
> registers/commands, or maybe I am missing it.
> 
> The chip datasheet does talk a lot about various MTP registers.
> Part of that register set is Write_protect_section and
> Read_protect_section. Maybe the PMBus registers are all read
> protected ?

There is a programming guide and register map on the Infineon site under 
"Additional Technical Information" here:

https://www.infineon.com/cms/en/product/power/dc-dc-converters/integrated-pol-voltage-regulators/irps5401m/

-- 
Robert Hancock
Senior Hardware Designer
SED Systems, a division of Calian Ltd.
Email: hancock@sedsystems.ca