Re: [PATCH 1/1] LinuxPPS: Pulse per Second support for Linux

From: Rodolfo Giometti
Date: Fri Feb 16 2007 - 15:43:35 EST

On Fri, Feb 16, 2007 at 07:12:08PM +0000, Russell King wrote:
> Yuck. Please. No. Doing it this way means you have to modify every
> single serial driver out there which is a mamouth task.
> > uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
> Did you not look to see what's in this helper? You'll find within here
> the following code:
> if ((port->flags & UPF_HARDPPS_CD) && status)
> hardpps();
> #endif
> which should've been a big sign lit up in bright lights in Times Square
> pointing you towards the right place to put your code.


> Why not continue to leave it as a decision of the administrator - if
> you want ports to default to having PPS support enabled, change all
> the registration to set UPF_HARDPPS_CD. But leave the admin with
> the ability to disable it.


> This means that PPS support is not available for any port which wasn't
> autoprobed at device discovery time. That seems quite restrictive.

How I can force probing for a specified uart port?

> Maybe it needs to be coupled with the setting/clearing of UPF_HARDPPS_CD ?

What do you think about? I should enable the PPS support only if the
userland sets the UPF_HARDPPS_CD flag?

Thanks for your comments,



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