From 794912cff6dba8b5e93948243299bb0b2cb11277 Mon Sep 17 00:00:00 2001 From: Michal Suchanek Date: Mon, 13 Jun 2016 17:46:50 +0000 Subject: spi: sunxi: expose maximum transfer size limit The sun4i spi hardware can trasfer at most 63 bytes of data without DMA support so report the limitation. Same for sun6i. Signed-off-by: Michal Suchanek Acked-by: Maxime Ripard Signed-off-by: Mark Brown --- drivers/spi/spi-sun4i.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/spi/spi-sun4i.c') diff --git a/drivers/spi/spi-sun4i.c b/drivers/spi/spi-sun4i.c index 1ddd9e2309b6..07ce7c97750e 100644 --- a/drivers/spi/spi-sun4i.c +++ b/drivers/spi/spi-sun4i.c @@ -167,6 +167,11 @@ static void sun4i_spi_set_cs(struct spi_device *spi, bool enable) sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); } +static size_t sun4i_spi_max_transfer_size(struct spi_device *spi) +{ + return SUN4I_FIFO_DEPTH - 1; +} + static int sun4i_spi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *tfr) @@ -394,6 +399,7 @@ static int sun4i_spi_probe(struct platform_device *pdev) master->bits_per_word_mask = SPI_BPW_MASK(8); master->dev.of_node = pdev->dev.of_node; master->auto_runtime_pm = true; + master->max_transfer_size = sun4i_spi_max_transfer_size; sspi->hclk = devm_clk_get(&pdev->dev, "ahb"); if (IS_ERR(sspi->hclk)) { -- cgit v1.2.3