On Mon, Jun 13, 2022 at 2:05 PM <andrea.merello@xxxxxx> wrote: > > From: Andrea Merello <andrea.merello@xxxxxx> > > Add a serdev driver for communicating to a BNO055 IMU via serial bus, and > enable the BNO055 core driver to work in this scenario. ... > + * This driver is besed on based > + * Plantower PMS7003 particulate matter sensor driver > + * Which is > + * Copyright (c) Tomasz Duszynski <tduszyns@xxxxxxxxx> ... > +/* > + * Read operation overhead: > + * 4 bytes req + 2byte resp hdr. > + * 6 bytes = 60 bit (considering 1start + 1stop bits). > + * 60/115200 = ~520uS + about 2500mS dealay -> ~3mS delay > + * In 3mS we could read back about 34 bytes that means 17 samples, this means > + * that in case of scattered read in which the gap is 17 samples or less it is reads > + * still convenient to go for a burst. > + * We have to take into account also IMU response time - IMU seems to be often > + * reasonably quick to respond, but sometimes it seems to be in some "critical > + * section" in which it delays handling of serial protocol. Because of this we > + * round-up to 22, which is the max number of samples, always bursting indeed. > + */ ... > +/* > + * Sends a read or write command. Send ... > +/* > + * Handler for received data; this is called from the reicever callback whenever receiver > + * it got some packet from the serial bus. The status tell us whether the tells > + * packet is valid (i.e. header ok && received payload len consistent wrt the > + * header). It's now our responsability to check whether this is what we responsibility > + * expected, of whether we got some unexpected, yet valid, packet. > + */ ... > + /* > + * New packet. > + * Check for its 1st byte, that identifies the pkt type. byte that > + */ -- With Best Regards, Andy Shevchenko
