On Mon, 2018-07-23 at 10:03 -0500, Aaron Sierra wrote: > > > /* Clear all PCI interrupts by reading INT0. No effect on > > > IIR > > > */ > > > ioread8(priv->virt + UART_EXAR_INT0); > > > > As I mentioned in previous message, this and below it better to be > > readb(). > > Hi Andy, > > Why better? Two points: - consistency with the existing code - no need to check for / use IO when you 100% sure there will be MMIO access only (Note, I put consistency first) > I've been under the impression that ioreadX() are the > preferred accessors Why do we need it? Why it's preferred here? > for the general case due to type checking and > general utility. They are typically implemented around readX() anyway. > The virtual address is mapped from an MMIO BAR, so all accesses will > be > MMIO in either case. > > Here's my (possibly dated) primary motivator: > > https://yarchive.net/comp/linux/io_space_accesses.html > > Has something changed that I'm not aware of? >From the same link: --- 8< --- 8< --- - if your device only supports MMIO, you might as well just use the old interfaces. --- 8< --- 8< --- See what I wrote above. > > > + /* Clear INT0 for Expansion Interface slave ports, too */ > > > + if (priv->board->num_ports > 8) > > > + ioread8(priv->virt + (8 * 0x400) + > > > UART_EXAR_INT0); > > > > 0x2000 is explicitly mentioned in the data sheet, so, I doubt we > > need to > > describe it as 8 * 0x400. > > I was conflicted on that, thinking showing the logic behind that value > might have some benefit, but I agree that 0x2000 would be more readily > identifiable within the manual. I'll follow your recommendation in the > version that I submit. Thanks! -- Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Intel Finland Oy -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
