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authorFabrice Gasnier <fabrice.gasnier@st.com>2018-02-23 13:51:01 +0100
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2018-04-28 17:17:59 +0200
commit4cfcb2bfdd07b130f05a3fb39edd6bfa2a59bf7a (patch)
treeb87452dc0efdff5a696e0b1dcc629ca61e2b3c9d /drivers/iio/adc
parentiio: adc: stm32-dfsdm: add check on max filter id (diff)
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linux-4cfcb2bfdd07b130f05a3fb39edd6bfa2a59bf7a.zip
iio: adc: stm32-dfsdm: add check on spi-max-frequency
spi-max-frequency is requested for SPI master mode (only), to tune output clock. It may happen requested frequency isn't reachable. Add explicit check, so probe fails with error in this case. Otherwise, output clock may simply be silently turned off (conversions fail). Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio/adc')
-rw-r--r--drivers/iio/adc/stm32-dfsdm-core.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c
index 6290332cfd3f..540d42cf6f4c 100644
--- a/drivers/iio/adc/stm32-dfsdm-core.c
+++ b/drivers/iio/adc/stm32-dfsdm-core.c
@@ -219,6 +219,11 @@ static int stm32_dfsdm_parse_of(struct platform_device *pdev,
}
priv->spi_clk_out_div = div_u64_rem(clk_freq, spi_freq, &rem) - 1;
+ if (!priv->spi_clk_out_div) {
+ /* spi_clk_out_div == 0 means ckout is OFF */
+ dev_err(&pdev->dev, "spi-max-frequency not achievable\n");
+ return -EINVAL;
+ }
priv->dfsdm.spi_master_freq = spi_freq;
if (rem) {