On Sun, Feb 20, 2011 at 3:38 PM, Ben Dooks <ben-i2c@xxxxxxxxx> wrote: <snip> >> > you know, there's a readsl() function that does this. >> I think readsl can't handle the possibly unaligned buf pointer. > > it does. see arch/arm/lib/io-writesl.S for proof. You're right, I traced the wrong definition of readsl/writesl >> > this whole function gives me the creeps, is there any reason why >> > we can't use the readsl or similar functions for this? >> Same here - readsl can't handle the alignment requirements, readsb >> can't handle the required 32 bit register read, and the bytes in the >> same word but after the end buf may not be part of buf, so byte writes >> to buf are required. > > You'll find it can, too. arch/arm/lib/io-readsl.S. I still think readsl doesn't work here. It may need to read 7 bytes, requiring 2 calls to readl, but 1 word write and 3 byte writes to buf. Using readsl for the whole buffer would overwrite the 8th byte. I can use readsl for the main loop, but I will still need to write the last 1-3 bytes separately. I could use readl and memcpy to do the last writes. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
