diff options
| -rw-r--r-- | Documentation/arm/Samsung-S3C24XX/Overview.txt | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/Documentation/arm/Samsung-S3C24XX/Overview.txt b/Documentation/arm/Samsung-S3C24XX/Overview.txt index 3af4d29a8938..89aa89d526ac 100644 --- a/Documentation/arm/Samsung-S3C24XX/Overview.txt +++ b/Documentation/arm/Samsung-S3C24XX/Overview.txt @@ -81,7 +81,8 @@ Adding New Machines Any large scale modifications, or new drivers should be discussed on the ARM kernel mailing list (linux-arm-kernel) before being - attempted. + attempted. See http://www.arm.linux.org.uk/mailinglists/ for the + mailing list information. NAND @@ -120,6 +121,43 @@ Clock Management various clock units +Platform Data +------------- + + Whenever a device has platform specific data that is specified + on a per-machine basis, care should be taken to ensure the + following: + + 1) that default data is not left in the device to confuse the + driver if a machine does not set it at startup + + 2) the data should (if possible) be marked as __initdata, + to ensure that the data is thrown away if the machine is + not the one currently in use. + + The best way of doing this is to make a function that + kmalloc()s an area of memory, and copies the __initdata + and then sets the relevant device's platform data. Making + the function `__init` takes care of ensuring it is discarded + with the rest of the initialisation code + + static __init void s3c24xx_xxx_set_platdata(struct xxx_data *pd) + { + struct s3c2410_xxx_mach_info *npd; + + npd = kmalloc(sizeof(struct s3c2410_xxx_mach_info), GFP_KERNEL); + if (npd) { + memcpy(npd, pd, sizeof(struct s3c2410_xxx_mach_info)); + s3c_device_xxx.dev.platform_data = npd; + } else { + printk(KERN_ERR "no memory for xxx platform data\n"); + } + } + + Note, since the code is marked as __init, it should not be + exported outside arch/arm/mach-s3c2410/, or exported to + modules via EXPORT_SYMBOL() and related functions. + Port Contributors ----------------- @@ -149,6 +187,7 @@ Document Changes 06 Mar 2005 - BJD - Added Christer Weinigel 08 Mar 2005 - BJD - Added LCVR to list of people, updated introduction 08 Mar 2005 - BJD - Added section on adding machines + 09 Sep 2005 - BJD - Added section on platform data Document Author --------------- |