Russell King - ARM Linux <[email protected]> writes: >> +++ b/drivers/i2c/busses/i2c-mxs.c >> ... >> + >> + /* >> + * internal buffer for handling non-dma mapable buffers; when message >> + * exceeds the (arbitrary) size of '8', a buffer will be kmalloc()'ed >> + * instead of using this attribute >> + */ >> + unsigned char xfer_buf[8]; > > Beware. Remember that DMA cache maintanence operates on a granularity of > a cache line, and make sure that you're not going to be upset should the > cache line be read by accessing the other members of this struct. It's > probably altogether safer if you kmalloc this buffer separately at driver > init time, and make it an "unsigned char *xfer_buf".
Yes; this is generally true. But the i2c-mxs.c driver is for the mxs where the i2c dma channel supports also only byte aligned addresses. Shall I mention this in the comment? Btw, there is only one patch; the '1/3' in the subject was created by mistake. Enrico -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
