device parameter patches

[Sascha Hauer]

Some device parameter patches.

Sascha

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Sascha Hauer (3):
      param: make return value of param getter function const
      devinfo: use accessor function for parameters
      dev_add_param: check if param exists already

 drivers/base/driver.c |    2 +-
 include/param.h       |    6 +++---
 lib/parameter.c       |   14 +++++++++-----
 3 files changed, 13 insertions(+), 9 deletions(-)