From: Prashanth K <quic_prashk@quicinc.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
<linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v7] usb: common: usb-conn-gpio: Set last role to unknown before initial detection
Date: Thu, 15 Jun 2023 19:52:32 +0530 [thread overview]
Message-ID: <d5561151-08bb-9f5f-aa51-44c5ad31976b@quicinc.com> (raw)
In-Reply-To: <2023061547-staleness-camper-ae8a@gregkh>
On 15-06-23 03:00 pm, Greg Kroah-Hartman wrote:
> On Wed, Jun 14, 2023 at 12:14:08PM +0300, Heikki Krogerus wrote:
>> On Wed, May 31, 2023 at 08:11:14PM +0530, Prashanth K wrote:
>>> Currently if we bootup a device without cable connected, then
>>> usb-conn-gpio won't call set_role() since last_role is same as
>>> current role. This happens because during probe last_role gets
>>> initialised to zero.
>>>
>>> To avoid this, added a new constant in enum usb_role, last_role
>>> is set to USB_ROLE_UNKNOWN before performing initial detection.
>>>
>>> While at it, also handle default case for the usb_role switch
>>> in cdns3, intel-xhci-usb-role-switch & musb/jz4740 to avoid
>>> build warnings.
>>>
>>> Fixes: 4602f3bff266 ("usb: common: add USB GPIO based connection detection driver")
>>> Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
>>> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>>> ---
>>> v7: Added default case in musb/jz4740.c & intel-xhci-usb-role-switch.c to
>>> avoid build warnings.
>>> v6: Moved USB_ROLE_UNKNOWN towards the end of enum usb_role.
>>> v5: Update commit text to mention the changes made in cdns3 driver.
>>> v4: Added Reviewed-by tag.
>>> v3: Added a default case in drivers/usb/cdns3/core.c as pointed out by
>>> the test robot.
>>> v2: Added USB_ROLE_UNKNWON to enum usb_role.
>>>
>>> drivers/usb/cdns3/core.c | 2 ++
>>> drivers/usb/common/usb-conn-gpio.c | 3 +++
>>> drivers/usb/musb/jz4740.c | 2 ++
>>> drivers/usb/roles/intel-xhci-usb-role-switch.c | 2 ++
>>> include/linux/usb/role.h | 1 +
>>> 5 files changed, 10 insertions(+)
>>
>> Just to be clear to everybody, that USB_ROLE_UNKNOWN is not handled in
>> drivers/usb/roles/class.c, so this patch is broken.
>>
>> But the whole approach is wrong. That USB_ROLE_UNKNOWN is clearly a
>> flag where the other values in enum usb_role are actual switch states.
>> So it does not belong there.
>>
>> In general, adding globals states like that just in order to work
>> around issues in single drivers is never a good idea IMO.
>
> Ok, let me go revert this from my tree, thanks for the review.
>
> greg k-h
In that case, can I resubmit v1 of this patch again, where I have used a
macro in usb-conn-gpio driver ? something like this.
@@ -27,6 +27,8 @@
#define USB_CONN_IRQF \
(IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT)
+#define USB_ROLE_UNKNOWN (USB_ROLE_NONE -1)
+
struct usb_conn_info {
struct device *dev;
struct usb_role_switch *role_sw;
@@ -257,6 +259,9 @@ static int usb_conn_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, info);
device_set_wakeup_capable(&pdev->dev, true);
+ /* Set last role to unknown before performing the initial detection */
+ info->last_role = USB_ROLE_UNKNOWN;
+
/* Perform initial detection */
usb_conn_queue_dwork(info, 0);
Thanks,
Prashanth K
next prev parent reply other threads:[~2023-06-15 14:23 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-31 14:41 [PATCH v7] usb: common: usb-conn-gpio: Set last role to unknown before initial detection Prashanth K
2023-05-31 14:47 ` Prashanth K
2023-06-13 9:58 ` Greg Kroah-Hartman
2023-06-13 11:10 ` Heikki Krogerus
2023-06-14 4:25 ` Prashanth K
2023-06-14 8:36 ` Heikki Krogerus
2023-06-14 9:14 ` Heikki Krogerus
2023-06-15 9:30 ` Greg Kroah-Hartman
2023-06-15 14:22 ` Prashanth K [this message]
2023-06-15 14:36 ` Greg Kroah-Hartman
2023-06-15 14:58 ` Prashanth K
2023-06-15 15:05 ` Greg Kroah-Hartman
2023-06-15 18:11 ` Prashanth K
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=d5561151-08bb-9f5f-aa51-44c5ad31976b@quicinc.com \
--to=quic_prashk@quicinc.com \
--cc=angelogioacchino.delregno@collabora.com \
--cc=gregkh@linuxfoundation.org \
--cc=heikki.krogerus@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=matthias.bgg@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).