linux-kernel - Re: [PATCH v5 3/3] OMAP2+: voltage: add check for missing PMIC info in vp init

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

Date:	Fri, 30 Sep 2011 15:14:49 -0700
From:	Kevin Hilman <khilman@...com>
To:	Paul Walmsley <paul@...an.com>
Cc:	Abhilash K V <abhilash.kv@...com>, linux-omap@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	tony@...mide.com, linux@....linux.org.uk, b-cousson@...com,
	aneesh@...com, santosh.shilimkar@...com,
	christian.gmeiner@...il.com
Subject: Re: [PATCH v5 3/3] OMAP2+: voltage: add check for missing PMIC info in vp init

Hi Paul,

Paul Walmsley <paul@...an.com> writes:

> On Fri, 30 Sep 2011, Abhilash K V wrote:
>
>> From: Abhilash K V <abhilash.kv@...com>
>> 
>> If PMIC info is not available in omap_vp_init(), abort.
>> 
>> Signed-off-by: Abhilash K V <abhilash.kv@...com>
>> ---
>>  arch/arm/mach-omap2/vp.c |    7 +++++++
>>  1 files changed, 7 insertions(+), 0 deletions(-)
>> 
>> diff --git a/arch/arm/mach-omap2/vp.c b/arch/arm/mach-omap2/vp.c
>> index 66bd700..0ed3d13 100644
>> --- a/arch/arm/mach-omap2/vp.c
>> +++ b/arch/arm/mach-omap2/vp.c
>> @@ -41,6 +41,13 @@ void __init omap_vp_init(struct voltagedomain *voltdm)
>>  	u32 val, sys_clk_rate, timeout, waittime;
>>  	u32 vddmin, vddmax, vstepmin, vstepmax;
>>  
>> +	if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
>> +		pr_err("%s: PMIC info requried to configure VP for "
>> +			"vdd_%s not populated.Hence cannot initialize VP\n",
>> +			__func__, voltdm->name);
>> +		return;
>> +	}
>> +
>
> Just wondering about the intent of this patch.  Is the goal here to not 
> call omap_vp_init() for chips that don't have a VP IP block?  If so, then 
> implementing code that does that directly seems like a better approach 
> than using the PMIC data?  Because it seems likely that even SoCs without 
> VP IP blocks will have PMICs on the board, right?

You're right, this isn't really relevant for this series since AM35x
doesn't have VP, and hence shouldn't even be calling omap_vp_init().

However, this does fix a bug on devices that do have VP where the VP is
initialized before PMIC info has been registered.

So, I'll queue this patch as a fix for the voltage layer, but it should
not have been included in the AM35x series.

Kevin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/