Re: [PATCH v2] nvmem: regmap: Fix nvmem size

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 20.12.23 13:38, Robin van der Gracht wrote:
> Hi Ahmad,
> 
> On 2023-12-20 10:00, Ahmad Fatoum wrote:
>> Hello Robin,
>>
>> Thanks for the fix.
>>
>> On 20.12.23 09:29, Robin van der Gracht wrote:
>>> -    if (roffset + rbytes > stride * regmap_get_max_register(map))
>>> +    if (roffset + rbytes > regmap_size_bytes(map) * stride)
>>
>> Shouldn't stride on the right hand side be dropped?
> 
> roffset = register index * stride.
> 
> I.e. 380 for register with index 95.
> 
> For stm32mp1x bsec:
>  map->format.val_bytes = 4
>  map->reg_stride = 4
> 
> regmap_size_bytes() = map->format.val_bytes * (95 + 1) / map->reg_stride = 96

Ouch. What have I been thinking when I named regmap_size_bytes() this way...

Change looks ok then, but we should really rename regmap_size_bytes()...

> 
> So the result with the stride on the right size is correct.
> 
> I moved stride from left to right to be consistent with the size calculation
> in nvmem_regmap_register_with_pp()
> 
> Kind regards,
> Robin
> 
> 
>>
>> Cheers,
>> Ahmad
>>
>>>          return -EINVAL;
>>>
>>>      for (i = roffset; i < roffset + rbytes; i += stride) {
>>> @@ -78,7 +78,7 @@ nvmem_regmap_register_with_pp(struct regmap *map, const char *name,
>>>      config.priv = map;
>>>      config.stride = 1;
>>>      config.word_size = 1;
>>> -    config.size = regmap_get_max_register(map) * regmap_get_reg_stride(map);
>>> +    config.size = regmap_size_bytes(map) * regmap_get_reg_stride(map);
>>>      config.cell_post_process = cell_post_process;
>>>      config.reg_write = nvmem_regmap_write;
>>>      config.reg_read = nvmem_regmap_read;
> 

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |