mtd: spi-nor: cadence-quadspi: Handle probe deferral while requesting DMA channel (935da5e5) · Commits · 戴 / test

dma_request_chan_by_mask() can throw EPROBE_DEFER if DMA provider is not yet probed. Currently driver just falls back to using PIO mode (which is less efficient) in this case. Instead return probe deferral error as is so that driver will be re probed once DMA provider is available. Signed-off-by:

Vignesh Raghavendra <vigneshr@ti.com> Reviewed-by:

Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by:

Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/20200601070444.16923-6-vigneshr@ti.com Signed-off-by:

Mark Brown <broonie@kernel.org>

drivers/mtd/spi-nor/controllers/cadence-quadspi.c

+13 −5

Original line number	Diff line number	Diff line
		@@ -1169,7 +1169,7 @@ static void cqspi_controller_init(struct cqspi_st *cqspi)
		cqspi_controller_enable(cqspi, 1);
		}

		static void cqspi_request_mmap_dma(struct cqspi_st *cqspi)
		static int cqspi_request_mmap_dma(struct cqspi_st *cqspi)
		{
		dma_cap_mask_t mask;

		@@ -1178,11 +1178,16 @@ static void cqspi_request_mmap_dma(struct cqspi_st *cqspi)

		cqspi->rx_chan = dma_request_chan_by_mask(&mask);
		if (IS_ERR(cqspi->rx_chan)) {
		int ret = PTR_ERR(cqspi->rx_chan);

		if (ret != -EPROBE_DEFER)
		dev_err(&cqspi->pdev->dev, "No Rx DMA available\n");
		cqspi->rx_chan = NULL;
		return;
		return ret;
		}
		init_completion(&cqspi->rx_dma_complete);

		return 0;
		}

		static const struct spi_nor_controller_ops cqspi_controller_ops = {
		@@ -1269,8 +1274,11 @@ static int cqspi_setup_flash(struct cqspi_st cqspi, struct device_node np)
		dev_dbg(nor->dev, "using direct mode for %s\n",
		mtd->name);

		if (!cqspi->rx_chan)
		cqspi_request_mmap_dma(cqspi);
		if (!cqspi->rx_chan) {
		ret = cqspi_request_mmap_dma(cqspi);
		if (ret == -EPROBE_DEFER)
		goto err;
		}
		}
		}

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