Messages in this thread Patch in this message | | | From | alexander.levin@verizon ... | Subject | [PATCH AUTOSEL for 4.9 24/24] iio: adc: ti-ads1015: add 10% to conversion wait time | Date | Wed, 22 Nov 2017 22:26:16 +0000 |
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From: Ladislav Michl <ladis@linux-mips.org>
[ Upstream commit fe895ac88b9fbdf2026f0bfd56c82747bb9d7c48 ]
As user's guide "ADS1015EVM, ADS1115EVM, ADS1015EVM-PDK, ADS1115EVM-PDK User Guide (Rev. B)" (http://www.ti.com/lit/ug/sbau157b/sbau157b.pdf) states at page 16: "Note that both the ADS1115 and ADS1015 have internal clocks with a ±10% accuracy. If performing FFT tests, frequencies may appear to be incorrect as a result of this tolerance range.", add those 10% to converion wait time.
Cc: Daniel Baluta <daniel.baluta@gmail.com> Cc: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Ladislav Michl <ladis@linux-mips.org> Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> --- drivers/iio/adc/ti-ads1015.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c index 472641fc890c..af05e20c986b 100644 --- a/drivers/iio/adc/ti-ads1015.c +++ b/drivers/iio/adc/ti-ads1015.c @@ -269,6 +269,7 @@ int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val) conv_time = DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr_old]); conv_time += DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr]); + conv_time += conv_time / 10; /* 10% internal clock inaccuracy */ usleep_range(conv_time, conv_time + 1); data->conv_invalid = false; } -- 2.11.0 | |