This is a note to let you know that I've just added the patch titled
iio: adc: ti-ads1015: add 10% to conversion wait time
to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: iio-adc-ti-ads1015-add-10-to-conversion-wait-time.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Wed Dec 6 17:39:55 CET 2017
From: Ladislav Michl ladis@linux-mips.org Date: Fri, 25 Aug 2017 07:39:16 +0200 Subject: iio: adc: ti-ads1015: add 10% to conversion wait time
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iio/adc/ti-ads1015.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/iio/adc/ti-ads1015.c +++ b/drivers/iio/adc/ti-ads1015.c @@ -269,6 +269,7 @@ int ads1015_get_adc_result(struct ads101
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; }
Patches currently in stable-queue which might be from ladis@linux-mips.org are
queue-4.9/iio-adc-ti-ads1015-add-10-to-conversion-wait-time.patch