Documentation/driver-api/sm501.rst

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27 peripheral set as platform devices for the specific drivers.
29 The core re-uses the platform device system as the platform device
30 system provides enough features to support the drivers without the
31 need to create a new bus-type and the associated code to go with it.
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37 Each peripheral has a view of the device which is implicitly narrowed to
38 the specific set of resources that peripheral requires in order to
41 The centralised memory allocation allows the driver to ensure that the
42 maximum possible resource allocation can be made to the video subsystem
43 as this is by-far the most resource-sensitive of the on-chip functions.
45 The primary issue with memory allocation is that of moving the video
47 occurs the memory footprint of the video subsystem changes.
49 Since video memory is difficult to move without changing the display
50 (unless sufficient contiguous memory can be provided for the old and new
51 modes simultaneously) the video driver fully utilises the memory area
52 given to it by aligning fb0 to the start of the area and fb1 to the end
53 of it. Any memory left over in the middle is used for the acceleration
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61 The platform device driver uses a set of platform data to pass
62 configurations through to the core and the subsidiary drivers
69 There is an errata (AB-5) affecting the selection of the
73 lock and hang the whole system. The driver will refuse to