[PATCH 0/4] Add DMA support for ti_am335x_adc driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




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] - http://pastebin.ubuntu.com/23211490/
[2] - http://pastebin.ubuntu.com/23211492/
[3] - http://pastebin.ubuntu.com/23211494/
[4] - git://git.ti.com/~mugunthanvnm/ti-linux-kernel/linux.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(-)

-- 
2.10.0.129.g35f6318

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]
  Powered by Linux