Re: [PATCH] serial_core: fix uart PORT_UNKNOWN handling

[gregkh@xxxxxxxxxxxxxxxxxxx]

On Wed, Apr 09, 2014 at 05:06:24PM +0200, Thomas Pfaff wrote:
> 
> On Wed, 9 Apr 2014, One Thousand Gnomes wrote:
> 
> > On Wed, 9 Apr 2014 13:22:14 +0200
> > Thomas Pfaff <tpfaff@xxxxxxx> wrote:
> > 
> > > 1. uart_change_pm ist called during uart_open and calls the uart pm function
> > >    without checking for PORT_UNKNOWN.
> > 
> > Removing this breaks other parts of the code assume that the port will be
> > powered up (notably setserial paths). So it makes sense that
> > uart_change_pm for a "none" port is a no-op but needs logic in the
> > setserial path to power up a port when we move none->known and power it
> > down on known->none
> > 
> 
> Then why not move uart_change_pm into uart_port_startup, where it will be called 
> when needed ?
> A reworked patch is below.
> 
> > > 2. uart_shutdown is called from uart_set_info and does not check it either.
> > 
> > I don't see why this one matters. We would have done
> > 
> > 	uart_startup
> > 		uart_port_startup
> > 			uport->type == PORT_UNKNOWN
> > 			return 1;
> > 		ASYNCB_INITIALIZED is not set
> > 
> > 	uart_shutdown
> > 		ASYNCB_INITIALISED is not set
> > 			Skip call to uart_port_shutdown
> > 
> > So that code looks correct to me.
> 
> I agree, i have overlooked this.
> 
> Signed-off-by: Thomas Pfaff <tpfaff@xxxxxxx>

Can you resend this in a format that I can apply this in?

thanks,

greg k-h
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