Re: [PATCH v4 3/3] i2c-ocores: sifive: add polling mode workaround for FU540-C000 SoC

From: Andrew Lunn
Date: Mon May 20 2019 - 08:43:46 EST


> @@ -406,7 +416,7 @@ static int ocores_xfer(struct i2c_adapter *adap,
> {
> struct ocores_i2c *i2c = i2c_get_adapdata(adap);
>
> - if (i2c->flags & OCORES_FLAG_POLL)
> + if ((i2c->flags & (OCORES_FLAG_POLL | OCORES_FLAG_BROKEN_IRQ)))
> return ocores_xfer_polling(adap, msgs, num);
> return ocores_xfer_core(i2c, msgs, num, false);
> }

You are not listening to what i said. All you need to know here is
that you must poll. It does not matter if the IRQ is broken or not.

> irq = platform_get_irq(pdev, 0);
> if (irq == -ENXIO) {
> - i2c->flags |= OCORES_FLAG_POLL;

If there is no interrupt, you need to poll. So keep this line.

> + /*
> + * Set a OCORES_FLAG_BROKEN_IRQ to enable workaround for
> + * FU540-C000 SoC in polling mode interface of i2c-ocore driver.
> + * Else enable default polling mode interface for SIFIVE/OCORE
> + * device types.
> + */
> + match = of_match_node(ocores_i2c_match, pdev->dev.of_node);
> + if (match && (long)match->data == TYPE_SIFIVE_REV0)
> + i2c->flags |= OCORES_FLAG_BROKEN_IRQ;

If it is a OCORE, IRQ is broken, so OR in OCORES_FLAG_BROKEN_IRQ.

>
> - if (!(i2c->flags & OCORES_FLAG_POLL)) {
> + if (!(i2c->flags & (OCORES_FLAG_POLL | OCORES_FLAG_BROKEN_IRQ))) {
> ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0,
> pdev->name, i2c);

Here you just need to know if you are polling. Broken IRQ does not
matter.

Andrew