[PATCH v4 0/2] powerpc/512x: add LocalPlus Bus FIFO device driver

Alexander Popov alex.popov at linux.com
Mon Oct 12 08:08:00 AEDT 2015

This driver for Freescale MPC512x LocalPlus Bus FIFO (called SCLPC
in the Reference Manual) allows Direct Memory Access transfers
between RAM and peripheral devices on LocalPlus Bus.

Changes in v3:
 - resource usage in probe() is fixed;
 - driver methods are made safe against remove();
 - dma_request_slave_channel() is used to get DMA channel number from
    the device tree;
 - chip select number concerned with the DMA transaction is determined
    from 'localbus' device tree node information;
 - register set is described as a structure;
 - symbolic names are given to shift counts to keep magic numbers
    out of the code;
 - choosing values for LPBFIFO BPT (bytes per transfer) and DMA maxburst
    is improved, so DMA transfer size has increased for some cases;
 - device tree binding for LPBFIFO is documented;
 - Kconfig and Makefile are improved;
 - email address "a13xp0p0v88 at gmail.com" is changed to a more pleasant
    alias "alex.popov at linux.com".

Changes in v4:
 - the race condition is fixed;
 - plenty of style fixes are made;
 - devm_* functions and EPROBE_DEFER are used in probe().

Alexander Popov (2):
  powerpc/512x: add LocalPlus Bus FIFO device driver
  powerpc/512x: add a device tree binding for LocalPlus Bus FIFO

 .../bindings/powerpc/fsl/mpc512x_lpbfifo.txt       |  21 +
 arch/powerpc/boot/dts/mpc5121.dtsi                 |  11 +-
 arch/powerpc/boot/dts/mpc5125twr.dts               |  11 +-
 arch/powerpc/configs/mpc512x_defconfig             |   1 +
 arch/powerpc/include/asm/mpc5121.h                 |  59 +++
 arch/powerpc/platforms/512x/Kconfig                |   6 +
 arch/powerpc/platforms/512x/Makefile               |   1 +
 arch/powerpc/platforms/512x/mpc512x_lpbfifo.c      | 539 +++++++++++++++++++++
 8 files changed, 646 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/powerpc/fsl/mpc512x_lpbfifo.txt
 create mode 100644 arch/powerpc/platforms/512x/mpc512x_lpbfifo.c


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