netdev - Re: imx7: USB modem reset causes modem to not re-connect

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Mon, 12 Dec 2022 16:01:25 -0300
From:   Fabio Estevam <festevam@...il.com>
To:     bjorn@...k.no, Peter Chen <peter.chen@...nel.org>,
        Marek Vasut <marex@...x.de>, Li Jun <jun.li@....com>
Cc:     netdev <netdev@...r.kernel.org>,
        USB list <linux-usb@...r.kernel.org>,
        Alexander Stein <alexander.stein@...tq-group.com>,
        Schrempf Frieder <frieder.schrempf@...tron.de>
Subject: Re: imx7: USB modem reset causes modem to not re-connect

On Mon, Dec 12, 2022 at 3:10 PM Fabio Estevam <festevam@...il.com> wrote:
>
> Hi,
>
> On an imx7d-based board running kernel 5.10.158, I noticed that a
> Quectel BG96 modem is gone after sending a reset command via AT:

Disabling runtime pm like this:

diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c
b/drivers/usb/chipidea/ci_hdrc_imx.c
index 9ffcecd3058c..e2a263d583f9 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.c
+++ b/drivers/usb/chipidea/ci_hdrc_imx.c
@@ -62,7 +62,6 @@ static const struct ci_hdrc_imx_platform_flag
imx6ul_usb_data = {
 };

 static const struct ci_hdrc_imx_platform_flag imx7d_usb_data = {
-       .flags = CI_HDRC_SUPPORTS_RUNTIME_PM,
 };

 static const struct ci_hdrc_imx_platform_flag imx7ulp_usb_data = {

makes the USB modem to stay connected after the reset command:

# microcom /dev/ttyUSB3
>AT+CFUN=1,1
OK
[   31.339416] usb 2-1: USB disconnect, device number 2
[   31.349480] option1 ttyUSB0: GSM modem (1-port) converter now
disconnected from ttyUSB0
[   31.358298] option 2-1:1.0: device disconnected
[   31.366390] option1 ttyUSB1: GSM modem (1-port) converter now
disconnected from ttyUSB1
[   31.374883] option 2-1:1.1: device disconnected
[   31.383359] option1 ttyUSB2: GSM modem (1-port) converter now
disconnected from ttyUSB2
[   31.391800] option 2-1:1.2: device disconnected
[   31.404700] option1 ttyUSB3: GSM modem (1-port) converter now
disconnected from ttyUSB3
# [   31.413261] option 2-1:1.3: device disconnected
[   36.151388] usb 2-1: new high-speed USB device number 3 using ci_hdrc
[   36.354398] usb 2-1: New USB device found, idVendor=2c7c,
idProduct=0296, bcdDevice= 0.00
[   36.362768] usb 2-1: New USB device strings: Mfr=3, Product=2, SerialNumber=4
[   36.370031] usb 2-1: Product: Qualcomm CDMA Technologies MSM
[   36.375818] usb 2-1: Manufacturer: Qualcomm, Incorporated
[   36.381355] usb 2-1: SerialNumber: 7d1563c1
[   36.389915] option 2-1:1.0: GSM modem (1-port) converter detected
[   36.397679] usb 2-1: GSM modem (1-port) converter now attached to ttyUSB0
[   36.412591] option 2-1:1.1: GSM modem (1-port) converter detected
[   36.420237] usb 2-1: GSM modem (1-port) converter now attached to ttyUSB1
[   36.434988] option 2-1:1.2: GSM modem (1-port) converter detected
[   36.442792] usb 2-1: GSM modem (1-port) converter now attached to ttyUSB2
[   36.457745] option 2-1:1.3: GSM modem (1-port) converter detected
[   36.465709] usb 2-1: GSM modem (1-port) converter now attached to ttyUSB3

Does anyone have any suggestions as to what could be the problem with
runtime pm?