spi: pxa2xx: Setup maximum supported DMA transfer length

BugLink: https://bugs.launchpad.net/bugs/1837952
commit ef070b4e4aa25bb5f8632ad196644026c11903bf upstream.

When the commit b6ced294fb61

   ("spi: pxa2xx: Switch to SPI core DMA mapping functionality")

switches to SPI core provided DMA helpers, it missed to setup maximum
supported DMA transfer length for the controller and thus users
mistakenly try to send more data than supported with the following
warning:

  ili9341 spi-PRP0001:01: DMA disabled for transfer length 153600 greater than 65536

Setup maximum supported DMA transfer length in order to make users know
the limit.

Fixes: b6ced294fb61 ("spi: pxa2xx: Switch to SPI core DMA mapping functionality")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 3a2e46e49405b5ea2bd2e17f982d4298578b72ae..c0e915d8da5d2bc0e1171a590d7a3207d00a897e 100644 (file)
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1698,6 +1698,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
                        platform_info->enable_dma = false;
                } else {
                        master->can_dma = pxa2xx_spi_can_dma;
+                       master->max_dma_len = MAX_DMA_LEN;
                }
        }