On Wed, Dec 17, 2014 at 3:53 AM, Suman Anna <s-anna@xxxxxx> wrote: >>> I think this logic in general will conflict between interrupt and poll >>> mode. send_data is supposed to return -EBUSY only in polling mode and >>> not in interrupt mode. >> What is the recommended error code for this case? BTW, omap-mailbox.c >> also return -EBUSY if mailbox is full. > > Looks like the mbox core doesn't care about the error, it's just > checking for non-success case. I made that comment based on the > documentation in last_tx_done. OMAP mailbox is always interrupt driven, > and it is very rare that we will ever hit the mbox full because of the > Tx-ready interrupt driven Tx ticker and also the h/w fifo. > > I see that your mailbox is very similar to OMAP mailbox though without > the h/w fifo, but you do have support for both polling and interrupt > modes in your code. OMAP mailbox can do that as well, but it's > inefficient to use polling so the driver is strictly interrupt driven. Yes, you are right. So, I think -EBUSY still can use it in interrupt case. >>>>> + >>>>> + mbox->mbox_base = devm_ioremap_resource(&pdev->dev, regs); >>>>> + if (IS_ERR(mbox->mbox_base)) >>>>> + return PTR_ERR(mbox->mbox_base); >>>>> + >>>>> + /* Check is it a sender or receiver? */ >>>>> + mbox->is_sender = altera_mbox_is_sender(mbox); >>>>> + >>>>> + mbox->irq = platform_get_irq(pdev, 0); >>>>> + if (mbox->irq >= 0) >>>>> + mbox->intr_mode = true; >>> >>> This seems to be a poor way of setting up the mode. Is it the same IP >>> block but different integration on different SoCs? Or on the same SoC, >>> and you can use it either by interrupt driven or by polling. >> Yes, it can use interrupt or polling mode depends on hardware configurations. >> It is a soft IP and can be configured with different hardware configurations. > > OK, the platform_get_irq suggests that this decision is made by having > or not having the interrupts property in the DT node, is that the only > way of differentiating this mode? Yes, we don't have other DTS property to identify the interrupt mode. Regards Ley Foon -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
