Categories

[HARP] Spi driver over GPIO working.. but too slow

Our first char driver is now working! We now have a very simple spi driver over GPIOs to communicate with a LED driver. After reading the signals with an analogical analyzer we realized it was just a bit faster (500khz)than using the registers from user-space (300khz). Thing is we were using a built-in function of gpio.h called  gpio_set_value which is too slow. After looking at its code we realized it’s doing too many things we don’t need. What we’re gonna work on tomorrow is to try to understand the code of the gpio-omap driver and copy parts of it for our char driver. That way we will be able to set our GPIOs much faster! After this part is done we will be on our final sprint to make our main program work with our drivers, using timers and interruption from our sensor.

Commentaires fermés.