diff options
| author | David Lechner <dlechner@baylibre.com> | 2025-07-01 16:37:56 -0500 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2025-07-13 15:36:25 +0100 |
| commit | db63e45a7da0678652c69f7cbed2cbf2a9922b39 (patch) | |
| tree | af82f0ed9b190f069b61ed56e910467dd69836d7 /include/linux/iio/adc | |
| parent | 1519bedf884c0a7c316906459d8c7da12113a8a9 (diff) | |
iio: adc: ad_sigma_delta: use spi_optimize_message()
Use spi_optimize_message() to improve the performance of buffered reads.
By setting up the SPI message and pre-optimizing it in the buffer
postenable callback, we can reduce overhead during each sample read.
A rough estimate shows that this reduced the CPU usage of the interrupt
handler thread from 22% to 16% using an EVAL-AD4112ARDZ board on a
DE10-Nano (measuring a single channel at the default 6.2 kHz sample
rate).
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20250701-iio-adc-ad7173-add-spi-offload-support-v3-8-42abb83e3dac@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'include/linux/iio/adc')
| -rw-r--r-- | include/linux/iio/adc/ad_sigma_delta.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/iio/adc/ad_sigma_delta.h b/include/linux/iio/adc/ad_sigma_delta.h index 5056677c9941..2037bb68b441 100644 --- a/include/linux/iio/adc/ad_sigma_delta.h +++ b/include/linux/iio/adc/ad_sigma_delta.h @@ -105,6 +105,8 @@ struct ad_sigma_delta { bool status_appended; /* map slots to channels in order to know what to expect from devices */ unsigned int *slots; + struct spi_message sample_msg; + struct spi_transfer sample_xfer[2]; u8 *samples_buf; /* @@ -116,6 +118,7 @@ struct ad_sigma_delta { */ u8 tx_buf[4] __aligned(IIO_DMA_MINALIGN); u8 rx_buf[16] __aligned(8); + u8 sample_addr; }; static inline int ad_sigma_delta_set_channel(struct ad_sigma_delta *sd, |