Commit 0b06d8cf authored Jun 14, 2016 by Michal Suchanek Committed by Mark Brown Jun 27, 2016

spi: sunxi: set maximum and minimum speed of SPI master



The speed limits are unset in the sun4i and sun6i SPI drivers.

The maximum speed of SPI master is used when maximum speed of SPI slave
is not specified. Also the __spi_validate function should check that
transfer speeds do not exceed the master limits.

The user manual for A10 and A31 specifies maximum
speed of the SPI clock as 100MHz and minimum as 3kHz.

Setting the SPI clock to out-of-spec values can lock up the SoC.

Signed-off-by: Michal Suchanek <hramrach@gmail.com>
--
v2:
new patch
v3:
fix constant style
Signed-off-by: Mark Brown <broonie@kernel.org>

parent 794912cf

drivers/spi/spi-sun4i.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -392,6 +392,8 @@ static int sun4i_spi_probe(struct platform_device *pdev)
		}

		sspi->master = master;
		master->max_speed_hz = 100 * 1000 * 1000;
		master->min_speed_hz = 3 * 1000;
		master->set_cs = sun4i_spi_set_cs;
		master->transfer_one = sun4i_spi_transfer_one;
		master->num_chipselect = 4;

drivers/spi/spi-sun6i.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -390,6 +390,8 @@ static int sun6i_spi_probe(struct platform_device *pdev)
		}

		sspi->master = master;
		master->max_speed_hz = 100 * 1000 * 1000;
		master->min_speed_hz = 3 * 1000;
		master->set_cs = sun6i_spi_set_cs;
		master->transfer_one = sun6i_spi_transfer_one;
		master->num_chipselect = 4;

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