From 56ede94a000bb9635b326db38baf66da6dfc174e Mon Sep 17 00:00:00 2001 From: Gabor Juhos Date: Wed, 14 Aug 2013 10:25:28 +0200 Subject: [PATCH] spi: limit default transfer speed to controller's max speed Since the 'spi: Support transfer speed checking in the core' change, the SPI core validates the desired speed of a given transfer against the minimum and maximum speeds supported by the controller. If the speed of a transfer is not specified, the core uses the maximum speed of the actual SPI device. However if the maximum speed of the actual device is greater than the maximum speed of the controller, the core will reject the transfer due to the aforementioned change. Change the code to use the maximum speed of the controller by default if that is below the device's maximum speed. Signed-off-by: Gabor Juhos Signed-off-by: Mark Brown --- drivers/spi/spi.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index c2899161ccac..2a20c32c8277 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1382,8 +1382,13 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) list_for_each_entry(xfer, &message->transfers, transfer_list) { if (!xfer->bits_per_word) xfer->bits_per_word = spi->bits_per_word; - if (!xfer->speed_hz) + if (!xfer->speed_hz) { xfer->speed_hz = spi->max_speed_hz; + if (master->max_speed_hz && + xfer->speed_hz > master->max_speed_hz) + xfer->speed_hz = master->max_speed_hz; + } + if (master->bits_per_word_mask) { /* Only 32 bits fit in the mask */ if (xfer->bits_per_word > 32) -- 2.34.1