[PATCH v3 5/5] tty/serial: Add Spreadtrum sc9836-uart driver support

Arnd Bergmann
2014-11-27T12:57:57Z

On Thursday 27 November 2014 19:59:46 Lyra Zhang wrote:
> 2014-11-27 2:29 GMT+08:00 Murali Karicheri <m-karicheri2@ti.com>:
> > On 11/25/2014 07:16 AM, Chunyan Zhang wrote:
> >>
> >> Add a full sc9836-uart driver for SC9836 SoC which is based on the
>
> >> +#include<linux/clk.h>
> >
> > How about sorting this includes? asm/irq.h go first followed linux/ in
> > alphabatical order?
>
> >> +static irqreturn_t sprd_handle_irq(int irq, void *dev_id)
> >> +{
> >> + struct uart_port *port = (struct uart_port *)dev_id;
> >> + u32 ims;
> >> +
> >> + ims = serial_in(port, SPRD_IMSR);
> >> +
> >> + serial_out(port, SPRD_ICLR, ~0);
> >> +
> >> + if (ims& (SPRD_IMSR_RX_FIFO_FULL |
> >> + SPRD_IMSR_BREAK_DETECT | SPRD_IMSR_TIMEOUT)) {
> >> + sprd_rx(irq, port);
> >> + }
> >> + if (ims& SPRD_IMSR_TX_FIFO_EMPTY)
> >> + sprd_tx(irq, port);
> >> +
> >> + return IRQ_HANDLED;
> >
> > You are always returning IRQ_HANDLED and this is registered as a SHARED irq.
> > Is there a chance this handler is called and the irq event doesn't
> > belong to this device?
> >
> > Murali
>
> You are right, this is not a SHARED irq. I'll pass 0 for irqflags when
> called 'devm_request_irq' in the next version patch.

I think you could also add

if (!ims)
return IRQ_NONE;

which would make it work on shared interrupt lines.

Arnd