[PATCH 2/2] mtd: rawnand: brcmnand: support "no-wp" DT property

[Rafał Miłecki]

On 2021-11-03 18:50, Florian Fainelli wrote:
> On 11/3/21 8:11 AM, Rafał Miłecki wrote:
>> From: Rafał Miłecki <rafal at milecki.pl>
>> 
>> Some boards may use WP-capable controller but still have WP not
>> connected. This change fixes:
>> [    1.175550] bcm63138_nand ff801800.nand: timeout on status poll 
>> (expected c0000040 got c00000c0)
>> [    1.184524] bcm63138_nand ff801800.nand: nand #WP expected on
>> [    1.285547] bcm63138_nand ff801800.nand: timeout on status poll 
>> (expected c0000040 got c00000c0)
>> [    1.294516] bcm63138_nand ff801800.nand: nand #WP expected on
>> [    1.395548] bcm63138_nand ff801800.nand: timeout on status poll 
>> (expected c0000040 got c00000c0)
>> [    1.404517] bcm63138_nand ff801800.nand: nand #WP expected on
>> 
>> Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
>> ---
>>  drivers/mtd/nand/raw/brcmnand/brcmnand.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c 
>> b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
>> index f75929783b94..8b6167457f0c 100644
>> --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
>> +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
>> @@ -714,7 +714,8 @@ static int brcmnand_revision_init(struct 
>> brcmnand_controller *ctrl)
>>  	if (ctrl->nand_version >= 0x0500)
>>  		ctrl->features |= BRCMNAND_HAS_1K_SECTORS;
>> 
>> -	if (ctrl->nand_version >= 0x0700)
>> +	if (ctrl->nand_version >= 0x0700 &&
>> +	    !of_property_read_bool(ctrl->dev->of_node, "no-wp"))
>>  		ctrl->features |= BRCMNAND_HAS_WP;
> 
> Should not this be a logical OR here or rather, should it be moved out
> of the check on ctrl->nand_version entirely? What revision of the NAND
> controller do you have on that chip?

It's NAND controller version 0x0701 (v7.1) and I think it's correct.

I think we want WP enabled on rev 7.0+ unless it was explicitly 
disabled.