tree cc3d76e62567f51f9051d3aabd224689a7bd17b8
parent 8a9c968b5342b057d96f0ae775b3103c77f38b85
author Jagannadha Sutradharudu Teki <jaganna@xilinx.com> 1388046297 +0530
committer Jagannadha Sutradharudu Teki <jaganna@xilinx.com> 1389433406 +0530

sf: Set quad enable bit support

This patch provides support to set the quad enable bit on flash.

quad enable bit needs to set before performing any quad IO
operations on respective SPI flashes.

Currently added set  quad enable bit for winbond and spansion flash
devices. stmicro flash doesn't require to set as qeb is volatile.
remaining flash devices support will add in future patches.

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>