[PATCH v4] flexcan: add err_irq handler for flexcan

[qiang.zhao at freescale.com]

On 07/02/2014 03:04 PM, Marc Kleine-Budde wrote:
> -----Original Message-----
> From: Marc Kleine-Budde [mailto:mkl at pengutronix.de]
> Sent: Wednesday, July 02, 2014 3:04 PM
> To: Zhao Qiang-B45475; linuxppc-dev at lists.ozlabs.org; wg at grandegger.com;
> linux-can at vger.kernel.org; Wood Scott-B07421
> Subject: Re: [PATCH v4] flexcan: add err_irq handler for flexcan
> 
> On 07/02/2014 04:00 AM, qiang.zhao at freescale.com wrote:
> >>> +static irqreturn_t flexcan_err_irq(int irq, void *dev_id) {
> >>> +	struct net_device *dev = dev_id;
> >>> +	struct flexcan_priv *priv = netdev_priv(dev);
> >>> +	struct flexcan_regs __iomem *regs = priv->base;
> >>> +	u32 reg_ctrl, reg_esr;
> >>> +
> >>> +	reg_esr = flexcan_read(&regs->esr);
> >>> +	reg_ctrl = flexcan_read(&regs->ctrl);
> >>> +
> >>> +	if (reg_esr & FLEXCAN_ESR_ALL_INT) {
> >>> +		if (reg_esr & FLEXCAN_ESR_ERR_INT)
> >>> +			flexcan_write(reg_ctrl & ~FLEXCAN_CTRL_ERR_MSK,
> >>> +				      &regs->ctrl);
> >>> +		flexcan_irq(irq, dev);
> >>
> >> I still don't understand why you need a special flexcan_err_irq()
> >> function. Why don't you just call:
> >>
> >> request_irq(priv->err_irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
> >>
> >> instead?
> >
> > Flexcan_irq is for flexcan normal interrupt(such as Message Buffer,
> Wake up and so on).
> > And it will return IRQ_HANDLED if flexcan_irq is triggered.
> > But err_irq is shared with other devices, it should return IRQ_HANDLED
> > when the interrupt is triggered by flexcan device, if not return
> IRQ_NONE.
> 
> What about fixing flexcan_irq() first and the make use of it?

Err_irq is a shared interrupt with other device, 
I hope that its handler is independent.
However, if you persist in your opinion, I will do it as you said.

> 
> Marc
> 
> --
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