From: Roger Quadros <rogerq@ti.com>
To: Peter Chen <peter.chen@nxp.com>
Cc: "pawell@cadence.com" <pawell@cadence.com>,
"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
"balbi@kernel.org" <balbi@kernel.org>,
"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Revert "usb: cdns3: core: quit if it uses role switch class"
Date: Tue, 24 Nov 2020 11:39:19 +0200 [thread overview]
Message-ID: <89067b6a-5b94-d7d2-b07a-f434c9e5e2bd@ti.com> (raw)
In-Reply-To: <20201124064242.GA32310@b29397-desktop>
Peter,
On 24/11/2020 08:43, Peter Chen wrote:
> On 20-11-23 13:50:51, Roger Quadros wrote:
>> This reverts commit 50642709f6590fe40afa6d22c32f23f5b842aed5.
>>
>> This commit breaks hardware based role switching on TI platforms.
>> cdns->role_sw is always going to be non-zero as it is a pointer
>> to the usb_role_switch instance. Some other means needs to be used
>> if hardware based role switching is not required by the platform.
>>
>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>> ---
>> drivers/usb/cdns3/core.c | 4 ----
>> 1 file changed, 4 deletions(-)
>>
>> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
>> index a0f73d4711ae..4c1445cf2ad0 100644
>> --- a/drivers/usb/cdns3/core.c
>> +++ b/drivers/usb/cdns3/core.c
>> @@ -280,10 +280,6 @@ int cdns3_hw_role_switch(struct cdns3 *cdns)
>> enum usb_role real_role, current_role;
>> int ret = 0;
>>
>> - /* Depends on role switch class */
>> - if (cdns->role_sw)
>> - return 0;
>> -
>> pm_runtime_get_sync(cdns->dev);
>>
>> current_role = cdns->role;
>> --
>
> Hi Roger,
>
> I am sorry about that. Do you use role switch /sys entry, if you have
> used, I prefer using "usb-role-switch" property at dts to judge if
> SoC OTG signals or external signals for role switch. If you have not
> used it, I prefer only setting cdns->role_sw for role switch use cases.
>
We use both hardware role switch and /sys entries for manually forcing
a certain role.
We do not set any "usb-role-switch" property at DTS.
Currently cdns->role_sw is being always set by driver irrespective of
any DT property, so this patch is clearly wrong and needs to be reverted.
What do you think?
cheers,
-roger
--
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
next prev parent reply other threads:[~2020-11-24 9:39 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-23 11:50 [PATCH] Revert "usb: cdns3: core: quit if it uses role switch class" Roger Quadros
2020-11-24 6:43 ` Peter Chen
2020-11-24 9:39 ` Roger Quadros [this message]
2020-11-24 9:57 ` Peter Chen
2020-11-24 10:33 ` Roger Quadros
2020-11-24 11:00 ` Heikki Krogerus
2020-11-24 11:47 ` Peter Chen
2020-11-24 12:22 ` Roger Quadros
2020-11-25 0:36 ` Peter Chen
2020-11-25 9:52 ` Roger Quadros
2020-11-25 10:14 ` Pawel Laszczak
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