The ADC has a 64 work depth fifo length which holds the ADC data
till the CPU reads. So when a user program needs a large ADC data
to operate on, then it has to do multiple reads to get its
buffer. Currently if the application asks for 4 samples per
channel with all 8 channels are enabled, kernel can provide only
3 samples per channel when all 8 channels are enabled (logs at
[1]). So with DMA support user can request for large number of
samples at a time (logs at [2]).

Tested the patch on AM437x-gp-evm and AM335x Boneblack with the
patch [3] to enable ADC and pushed a branch for testing [4]

[1] -
[2] -
[3] -
[4] - git:// iio-dma

Mugunthan V N (4):
  mfd: ti_am335x_tscadc: store physical address
  drivers: iio: ti_am335x_adc: add dma support
  ARM: dts: am33xx: add DMA properties for tscadc
  ARM: dts: am4372: add DMA properties for tscadc

 arch/arm/boot/dts/am33xx.dtsi        |   2 +
 arch/arm/boot/dts/am4372.dtsi        |   2 +
 drivers/iio/adc/ti_am335x_adc.c      | 160 ++++++++++++++++++++++++++++++++++-
 drivers/mfd/ti_am335x_tscadc.c       |   1 +
 include/linux/mfd/ti_am335x_tscadc.h |   8 ++
 5 files changed, 170 insertions(+), 3 deletions(-)


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