lkml.org 
[lkml]   [2017]   [May]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: gpio-exar: Why filtering out Commtech devices?
From
Date
On 2017-05-23 16:33, Technical Support wrote:
> Both the PCI and the PCIe cards use the MPIO pins and the device driver
> actually sets the pins as outputs after registering the device with the
> PCI core. So the changes made to the default settings shouldn't break
> anything.
>
> Do the new default settings keep the UART_EXAR_MPIOINT_X_X values at
> 0x00 to disable their interrupts?

Look at
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git/commit/?h=tty-next&id=7dea8165f1d6434dc7572004363f86339f0f4322

Interrupts remain off, but all pins are now inputs. Again, if the logic
on the PCIe cards need any of them to be driven low, my patch causes a
regression. In that case, we also need to make the MPIO setup card-specific.

Thanks,
Jan

>
> -Landon
>
> Commtech, Inc.
> Voice: 316-636-1131 <tel:%28316%29%20636-1131>
> http://www.fastcomproducts.com
>
>
>
>
> On Mon, May 22, 2017 at 1:18 PM, Jan Kiszka <jan.kiszka@siemens.com
> <mailto:jan.kiszka@siemens.com>> wrote:
>
> On 2017-05-22 18:24, Jan Kiszka wrote:
> > On 2017-05-22 17:17, Technical Support wrote:
> >> Hello,
> >>
> >> The Exar MPIO pins are used by our device driver to control features of
> >> the line driver and can't be used as GPIO pins. I agree, the condition
> >> can be moved to 8250_exar prior to a platform device being created for
> >> the gpio_exar driver.
> >>
> >
> > Thanks a lot for the feedback! I will send a refactoring patch.
>
> Hmm, are you possibly talking about PCI device with the IDs 0x2, 0x4,
> 0xa, 0xb (4222PCI335, 4224PCI335, 2324PCI335, 2328PCI335), because those
> actually set the GPIOs for apparent internal reasons. However,
> 0x20..0x22 (4222PCIE, 4224PCIE, 4228PCIE) already share setup_gpio() via
> pci_xr17v35x_setup(), and that looks different.
>
> I'm also asking again because we just changed the default MPIO settings
> for the latter to all inputs. If you depended on them to be all outputs
> and 0, we may have broken something.
>
> Thanks,
> Jan
>
> --
> Siemens AG, Corporate Technology, CT RDA ITP SES-DE
> Corporate Competence Center Embedded Linux
>
>

--
Siemens AG, Corporate Technology, CT RDA ITP SES-DE
Corporate Competence Center Embedded Linux

\
 
 \ /
  Last update: 2017-05-23 17:06    [W:1.047 / U:0.760 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site