diff options
author | Michael Hennerich <michael.hennerich@analog.com> | 2021-01-14 17:42:17 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-23 15:36:56 +0100 |
commit | 22be6fa087395d9191c49f8442d454961b7b3212 (patch) | |
tree | 88d699396398264cdb8b5e8a2539c8b0ac55c752 | |
parent | 4f0fca0e17b174a00580ae0411fbb64b81d1e967 (diff) |
spi: cadence: cache reference clock rate during probe
commit 4d163ad79b155c71bf30366dc38f8d2502f78844 upstream.
The issue is that using SPI from a callback under the CCF lock will
deadlock, since this code uses clk_get_rate().
Fixes: c474b38665463 ("spi: Add driver for Cadence SPI controller")
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210114154217.51996-1-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/spi/spi-cadence.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c index 5a6749881ff9..05b5df04f3b8 100644 --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -116,6 +116,7 @@ struct cdns_spi { void __iomem *regs; struct clk *ref_clk; struct clk *pclk; + unsigned int clk_rate; u32 speed_hz; const u8 *txbuf; u8 *rxbuf; @@ -257,7 +258,7 @@ static void cdns_spi_config_clock_freq(struct spi_device *spi, u32 ctrl_reg, baud_rate_val; unsigned long frequency; - frequency = clk_get_rate(xspi->ref_clk); + frequency = xspi->clk_rate; ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR_OFFSET); @@ -557,8 +558,9 @@ static int cdns_spi_probe(struct platform_device *pdev) master->set_cs = cdns_spi_chipselect; master->mode_bits = SPI_CPOL | SPI_CPHA; + xspi->clk_rate = clk_get_rate(xspi->ref_clk); /* Set to default valid value */ - master->max_speed_hz = clk_get_rate(xspi->ref_clk) / 4; + master->max_speed_hz = xspi->clk_rate / 4; xspi->speed_hz = master->max_speed_hz; master->bits_per_word_mask = SPI_BPW_MASK(8); |