On Tuesday 30 October 2007, Bryan Wu wrote: > Current SPI driver enables SPI controller and set the SPI baud register > for each SPI transfer. But, they should never be changed within a SPI > message session, in which seveal SPI transfers are pumped.
That's actually not true. If a driver sets spi_transfer.max_speed_hz to a nonzero value that's different from the previous bit rate (which may be spi_device.max_speed_hz), it should be updated before that transfer segment. Example, sometimes data can't be clocked out at the same rate commands can be clocked in. Similarly with spi_transfer.bits_per_word ... again, it's very possible that commands and data have different sizes. Of course, if those values don't change, there'd be no point in reconfiguring any aspect of those communications parameters... I'll be forwarding this patch, since this looks like another case where the main effect of the patch doesn't match its description and since this patch series has taken too long already. (Does this patch even really relate primarily to working with an ST M25P16 flash part??) Though it'd be reasonable to be more hard-nosed about this and insist on another go-around for thesse patches. (Making this the fifth one??) But I *STRONGLY* suggest someone revisit the issue of whether those two per-transfer options are now being handled correctly. As well as update procedures so that the patch comments start to have a direct correspondence to what the patches have changed... - Dave > This patch > move move SPI setting to the begining of a message session. And never > disables SPI controller until an error occurs. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ spi-devel-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/spi-devel-general
