Hi, On Tue, Oct 9, 2018 at 9:12 AM Stephen Boyd <swb...@chromium.org> wrote: > > Quoting Doug Anderson (2018-10-08 16:52:36) > > Hi, > > > > On Mon, Oct 8, 2018 at 4:43 PM Stephen Boyd <swb...@chromium.org> wrote: > > > > + mas->irq = platform_get_irq(pdev, 0); > > > > + if (mas->irq < 0) { > > > > + ret = mas->irq; > > > > + dev_err(&pdev->dev, "Err getting IRQ %d\n", ret); > > > > + goto spi_geni_probe_runtime_disable; > > > > + } > > > > > > Nitpick: If you got the irq earlier before allocating anything then > > > nothing has > > > to be put on failure path. > > > > I think this might have been in response to previous feedback from you > > suggesting that we should get the irq as late as possible. Ah, here > > ya go: > > > > https://lkml.kernel.org/r/153780767551.119890.9339380838620508...@swboyd.mtv.corp.google.com > > Yes I suggested we register for the irq as last as possible, but I > didn't suggest calling platform_get_irq() this late. It could be called > earlier so that if there isn't any irq then nothing to do besides return > failure.
Ah, you're suggesting separating the platform_get_irq() and the request_irq() so that we call platform_get_irq() as the first thing in the function but don't do the request_irq() until later. Yeah, that could be done and I guess if you feel strongly about it I wouldn't object to the change, but I don't feel it buys us a lot and I kind of like keeping the two next to each other. Specifically why I don't think it buys us a lot: 1. You still need the "dev_err" print, right? platform_get_irq() doesn't automatically print errors for you I think. 2. You now need a local variable "irq". By putting the platform_get_irq() before the memory allocation you now can't store it directly in mas->irq. We could try using "ret" as a temporary variable but that seems worse in this case since it'd be a bit fragile. 3. You don't get rid of any error labels / error handling so we don't really save any code When I tried this my diffstat says 8 lines added and 7 removed, so a net increase in LOC FWIW. I'm relying in gmail so my patch will be whitespace-damaged (sigh), but you can find a clean one at: https://chromium.googlesource.com/chromiumos/third_party/kernel/+/e0325d618e209c22379e3a4269c14627b19243a8%5E%21/#F0 ...the basic idea is this though: @@ -543,6 +543,13 @@ struct spi_geni_master *mas; struct resource *res; struct geni_se *se; + int irq; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "Err getting IRQ %d\n", irq); + return irq; + } spi = spi_alloc_master(&pdev->dev, sizeof(*mas)); if (!spi) @@ -553,6 +560,7 @@ mas->dev = &pdev->dev; mas->se.dev = &pdev->dev; mas->se.wrapper = dev_get_drvdata(pdev->dev.parent); + mas->irq = irq; se = &mas->se; spi->bus_num = -1; @@ -589,13 +597,6 @@ if (ret) goto spi_geni_probe_runtime_disable; - mas->irq = platform_get_irq(pdev, 0); - if (mas->irq < 0) { - ret = mas->irq; - dev_err(&pdev->dev, "Err getting IRQ %d\n", ret); - goto spi_geni_probe_runtime_disable; - } - ret = request_irq(mas->irq, geni_spi_isr, IRQF_TRIGGER_HIGH, "spi_geni", spi); if (ret) -Doug