On Fri, Jun 22, 2018 at 12:49 PM, Boris Brezillon <boris.brezillon@xxxxxxxxxxx> wrote: > Add a driver for Cadence I3C master IP. The driver seems very well-written and shows that the framework got that side of the interface right. Just one thing I noticed: > + > +static void cdns_i3c_master_handle_ibi(struct cdns_i3c_master *master, > + u32 ibir) > + > + for (i = 0; i < IBIR_XFER_BYTES(ibir); i += 4) { > + u32 tmp = readl(master->regs + IBI_DATA_FIFO); > + > + for (j = 0; j < 4 && i + j < dev->ibi->max_payload_len; j++) > + buf[i + j] = tmp >> (j * 8); > + } This seems to be a rather inefficient way to open-code a readsl(). I suppose you need to handle length that is not a multiple of 4, right? Maybe do it like size_t length = IBIR_XFER_BYTES(ibir); readsl(master->regs + IBI_DATA_FIFO, buf, length & ~3); if (length & 3) { u32 tmp = __raw_readl(master->regs + IBI_DATA_FIFO); memcpy(buf + length & ~3, length & 3); } Arnd -- 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