On Wednesday, July 23, 2014 at 03:57:35 PM, Herbert Xu wrote: > On Sat, May 24, 2014 at 02:00:03PM +0200, Marek Vasut wrote: > > > + } > > > +#endif > > > + > > > +#ifdef CONFIG_CRYPTO_DEV_SUNXI_SS_MD5 > > > + err = crypto_register_shash(&sunxi_md5_alg); > > > > Do not use shash for such device. This is clearly and ahash (and async in > > general) device. The rule of a thumb here is that you use sync algos only > > for devices which have dedicated instructions for computing the > > transformation. For devices which are attached to some kind of bus, you > > use async algos (ahash etc). > > I'm sorry that I didn't catch this earlier but there is no such > rule. > > Unless you need the async interface you should stick to the sync > interfaces for the sake of simplicity. > > We have a number of existing drivers that are synchronous but > using the async interface. They should either be converted > over to the sync interface or made interrupt-driven if possible. Sure, but this device is interrupt driven and uses DMA to feed the crypto engine, therefore async, right ? Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html