[PATCH v6 1/2] tty: serial: Cleanup the bit shift with macro

Crescent CY Hsieh crescentcy.hsieh at moxa.com
Thu Jan 18 00:14:41 PST 2024


On Thu, Jan 18, 2024 at 08:01:58AM +0100, Greg KH wrote:
> On Wed, Jan 17, 2024 at 03:56:23PM +0100, Christoph Niedermaier wrote:
> > >  struct serial_rs485 {
> > >  	__u32	flags;
> > > -#define SER_RS485_ENABLED		(1 << 0)
> > > -#define SER_RS485_RTS_ON_SEND		(1 << 1)
> > > -#define SER_RS485_RTS_AFTER_SEND	(1 << 2)
> > 
> > In the old definition (1 << 3) wasn't used.
> > 
> > > -#define SER_RS485_RX_DURING_TX		(1 << 4)
> > > -#define SER_RS485_TERMINATE_BUS		(1 << 5)
> > > -#define SER_RS485_ADDRB			(1 << 6)
> > > -#define SER_RS485_ADDR_RECV		(1 << 7)
> > > -#define SER_RS485_ADDR_DEST		(1 << 8)
> > > +#define SER_RS485_ENABLED		_BITUL(0)
> > > +#define SER_RS485_RTS_ON_SEND		_BITUL(1)
> > > +#define SER_RS485_RTS_AFTER_SEND	_BITUL(2)
> > > +#define SER_RS485_RX_DURING_TX		_BITUL(3)
> > 
> > Isn't it a break if number 3 isn't skipped here as well?

Sorry I might have misunderstood the meaning of "broke userspace".

In this case, does it imply splitting the "cleanup" patch and the "add
feature" patch, or leaving the third bit unused? Or perhaps both?

---
Sincerely,
Crescent Hsieh



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