From cc71c42b3dc1085d3e72dfa5603e827b9eb59da1 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Tue, 25 Jul 2023 11:02:27 -0700 Subject: [PATCH] spi: spi-qcom-qspi: Add mem_ops to avoid PIO for badly sized reads In the patch ("spi: spi-qcom-qspi: Fallback to PIO for xfers that aren't multiples of 4 bytes") we detect reads that we can't handle properly and fallback to PIO mode. While that's correct behavior, we can do better by adding "spi_controller_mem_ops" for our controller. Once we do this then the caller will give us a transfer that's a multiple of 4-bytes so we can DMA. Fixes: b5762d95607e ("spi: spi-qcom-qspi: Add DMA mode support") Signed-off-by: Douglas Anderson Reviewed-by: Vijaya Krishna Nivarthi Link: https://lore.kernel.org/r/20230725110226.2.Id4a39804e01e4a06dae9b73fd2a5194c4c7ea453@changeid Signed-off-by: Mark Brown --- drivers/spi/spi-qcom-qspi.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c index db1dd133762e4b..1954c39b3d089c 100644 --- a/drivers/spi/spi-qcom-qspi.c +++ b/drivers/spi/spi-qcom-qspi.c @@ -666,6 +666,30 @@ static irqreturn_t qcom_qspi_irq(int irq, void *dev_id) return ret; } +static int qcom_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) +{ + /* + * If qcom_qspi_can_dma() is going to return false we don't need to + * adjust anything. + */ + if (op->data.nbytes <= QSPI_MAX_BYTES_FIFO) + return 0; + + /* + * When reading, the transfer needs to be a multiple of 4 bytes so + * shrink the transfer if that's not true. The caller will then do a + * second transfer to finish things up. + */ + if (op->data.dir == SPI_MEM_DATA_IN && (op->data.nbytes & 0x3)) + op->data.nbytes &= ~0x3; + + return 0; +} + +static const struct spi_controller_mem_ops qcom_qspi_mem_ops = { + .adjust_op_size = qcom_qspi_adjust_op_size, +}; + static int qcom_qspi_probe(struct platform_device *pdev) { int ret; @@ -750,6 +774,7 @@ static int qcom_qspi_probe(struct platform_device *pdev) if (of_property_read_bool(pdev->dev.of_node, "iommus")) master->can_dma = qcom_qspi_can_dma; master->auto_runtime_pm = true; + master->mem_ops = &qcom_qspi_mem_ops; ret = devm_pm_opp_set_clkname(&pdev->dev, "core"); if (ret)