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  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:   Fri, 27 Oct 2017 10:21:09 +0800
From:   AceLan Kao <>
To:     Alan Cox <>
Cc:, Darren Hart <>,
        Andy Shevchenko <>,
        LKML <>,
Subject: Re: [PATCH] platform/x86: dell-uart-backlight: new backlight driver

Hi Alex,

2017-10-27 0:10 GMT+08:00 Alan Cox <>:
>> > +static int __init dell_uart_bl_init(void)
>> > +{
>> > +   ftty = filp_open("/dev/ttyS0", O_RDWR | O_NOCTTY | O_NDELAY, 0);
> You have no idea what name is assigned. This doesn't work.
Yes, I did. The port is defined in BIOS as PNP0501 uart port,
so the port will be registered by 8250 PNP driver as ttyS* device.
And consider it's defined in the BIOS, so it should be the first uart
port on the system,
and ttyS0 would be his name.

> This isn't the way to do it any more because the 'tty from kernel'
> problem finally got fixed. You can attach it as a serdev directly to the
> kernel.
> Take a look at serdev_tty_port_register/serdev_tty_port_unreg
Yes, I'm studying serdev, but currently there are not many examples
for reference,
so I still have no clues how to implement it by serdev.
I'll try using serdev_tty_port_register/serdev_tty_port_unreg to
re-implement the driver.

> Alan

Chia-Lin Kao(AceLan)
E-Mail: (s/AT/@/)

Powered by blists - more mailing lists