Messages in this thread | | | Date | Sun, 26 Dec 2021 06:45:41 -0500 | From | "Gabriel L. Somlo" <> | Subject | Re: [PATCH v5 3/3] mmc: Add driver for LiteX's LiteSDCard interface |
| |
Hi Andy,
Thanks for the feedback!
On Sat, Dec 25, 2021 at 06:43:22PM +0200, Andy Shevchenko wrote: > On Wed, Dec 15, 2021 at 10:00 PM Gabriel Somlo <gsomlo@gmail.com> wrote: > > > > LiteX (https://github.com/enjoy-digital/litex) is a SoC framework > > that targets FPGAs. LiteSDCard is a small footprint, configurable > > SDCard core commonly used in LiteX designs. > > > > The driver was first written in May 2020 and has been maintained > > cooperatively by the LiteX community. Thanks to all contributors! > > ... > > > + int ret; > > + > > + host->irq = platform_get_irq_optional(host->dev, 0); > > + if (host->irq <= 0) { > > + dev_warn(dev, "Failed to get IRQ, using polling\n"); > > + goto use_polling; > > + } > > [Same comment as per v3.]
> This is wrong. It missed the deferred probe, for example. > > The best approach is > > ret = platform_get_irq_optional(...); > if (ret < 0 && ret != -ENXIO) > return ret; > if (ret > 0) > ...we got it... > > It will allow the future API fix of platform_get_irq_optional() to be > really optional.
Thanks for the example. I still need to work in a decision to use polling, though. How about something like this instead:
ret = platform_get_irq_optional(...); if (ret == -ENXIO) goto use_polling; if (ret < 0) return ret; // deferred probe (-EAGAIN likely?) if (ret > 0) ...we got it, keep going...
> > ... > > > +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT > > Why under ifdeffery?
Because I only want to do it on 64-bit capable architectures.
The alternative would be to call
dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
on *all* architectures, but ignore the returned error (-EIO, presumably on architetures that only support 32-bit DMA).
Do you think that would be cleaner?
Thanks, --Gabriel
> > + /* increase from default 32 on 64-bit-DMA capable architectures */ > > + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); > > + if (ret) > > + goto err; > > +#endif > > With Best Regards, > Andy Shevchenko
| |