On Wed, 4 Feb 2009, Mike Frysinger wrote: > On Wednesday 04 February 2009 17:39:45 Jean-Christophe PLAGNIOL-VILLARD wrote: > > On 17:59 Wed 04 Feb , Guennadi Liakhovetski wrote: > > > Fix 8 and 16-bit transfers in mxc_spi driver and a wrong pointer in the > > > free routine. > > > > > > Signed-off-by: Guennadi Liakhovetski <l...@denx.de> > > > --- > > > > > > No SPI custodian, so, Jean-Christophe will have to Ack it? > > > > I'd like to have Mike and Haaward ack too > > i dont have any arm hardware let alone familiar with any hardware-level > things > like the SPI controller. so from a quick high level look ... > > does this controller actually support transfers that arent a multiple of 8 ?
Yes, it does. > if the smallest increment you can do is 8bits, then you should be rejecting > anything that isnt a multiple of it rather than holding the user's hand. as > for the assumption that "more than 32bits means do 32bit transfers", that > sounds plain wrong to me. u-boot should do exactly as instructed and nothing > more/less. so if the user tries to send 40bits, that better be 40bits and > not > 64bits. That's what my patch would do, but it is actually unclear to me what you should do for 40 bits? Do you want to send 32 + 8 or 20 + 20 or?.. In fact, I would reject if (bitlen > 32 && (bitlen & 31)). But, for example, mpc8xxx_spi.c also first sends data in 32-bit chunks, and then the rest. But I just noticed there is another bug in my driver, the bit-length in the control register is set wrongly if (bitlen > 32). Also, the function can be simplified by putting the 32-bit loop bofore residue transfer. I'll change both in the next revision. > the spi_free_slave() change looks correct ... not that it should change the > generated code as spi_slave is the first member of mxc_spi_slave, so they'll > be the same pointer and gcc will do the right thing. Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: off...@denx.de _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
