On Fri, Feb 22, 2019 at 03:11:58PM +0100, Hans de Goede wrote: > The 2 callers of fusb302_set_cc_polarity both call fusb302_set_cc_pull > directly before calling fusb302_set_cc_polarity, this is not ideal for > 2 reasons: > > 1) fusb302_set_cc_pull uses the cached polarity when applying pull-ups, > which maybe changed immediately afterwards, to fix this set_cc_polarity > already does the pull-up setting. > > 2) Both touch the SWITCHES0 register in a r-w-modify cycle, this leads to > read reg, write reg, read reg, write reg. If we fold the setting of > the pull-downs into fusb302_set_cc_polarity then not only can we avoid > doing the reads / writes twice, at this point we set all bits, so we > can skip the read, turning 4 (slowish) i2c-transfers into 1. > > Doing this also avoids the need to cache the pull_up state in > struct fusb302_chip. > > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> > --- > drivers/usb/typec/tcpm/fusb302.c | 48 +++++++++++--------------------- > 1 file changed, 16 insertions(+), 32 deletions(-) It would be nice to get some people to review/ack this series before I take it (hint...) thanks, greg k-h
