Re: Warnings for invalid VDD (sdhci-s3c)
From: Krzysztof Kozlowski
Date: Thu Mar 24 2016 - 04:43:14 EST
On 24.03.2016 17:24, Jisheng Zhang wrote:
> On Thu, 24 Mar 2016 17:09:27 +0900 Jaehoon Chung wrote:
>> On 03/24/2016 04:58 PM, Jisheng Zhang wrote:
>>> On Thu, 24 Mar 2016 16:28:56 +0900 Krzysztof Kozlowski wrote:
>>>> After 918f4cbd4340 ("mmc: sdhci: restore behavior when setting VDD via
>>>> external regulator") On Trats2 board I see warnings for invalid VDD
>>>> value (2.8V):
>>>> [ 3.119656] ------------[ cut here ]------------
>>>> [ 3.119666] WARNING: CPU: 3 PID: 90 at
>>>> ../drivers/mmc/host/sdhci.c:1234 sdhci_do_set_ios+0x4cc/0x5e0
>>>> [ 3.119669] mmc0: Invalid vdd 0x10
>>> Per my understanding, the wrong vdd indicates a wrong ocr, what's the voltage of
>>> this host's vmmc regulator?
>> As i know, it's fixed-voltage with gpio on trats2. It's 2.8V.
>> I didn't check this entirely..need to check ocr value.
> I may know the reason. the vmmc is 2.8v, then mmc_regulator_get_supply() convert
> the value to a ocr as 0x10. The key here is that the 2.8v is invalid in SDHCI
> case and isn't accepted by current sdhci driver.
Yeah, I already wrote that. It is the part of the warning and my email.
Our regulator is fixed at 2.8 which is 0x10. :)
> I dunno the elegant solution to handle this case, let's wait for sdhci maintainers