linux/drivers/usb/typec
Hans de Goede daf81d0137 usb: typec: fusb302: Refactor / simplify tcpm_set_cc()
After commit ea3b4d5523 ("usb: typec: fusb302: Resolve fixed power role
contract setup"), tcpm_set_cc always calls fusb302_set_toggling.

Before this refactor tcpm_set_cc does the following:

1) fusb302_set_toggling(TOGGLING_MODE_OFF),
   this sets both FUSB_REG_MASK_BC_LVL and FUSB_REG_MASK_COMP_CHNG.
2) fusb302_set_cc_pull(...).
3) "reset cc status".
4) if pull-up fusb302_set_src_current(...).
5) if pull-up or pull-down enable bc-lvl resp comp-chng irq.
6) fusb302_set_toggling(new-toggling-mode), which again
   sets both FUSB_REG_MASK_BC_LVL and FUSB_REG_MASK_COMP_CHNG disabling
   the just enabled irq. fusb302_set_toggling is skipped when the new
   toggling mode is TOGGLING_MODE_OFF because this is already done in 1,
   note in this case 5) is a no-op.

When we are toggling the bits set by fusb302_set_cc_pull will be ignored
until we turn toggling off, so we can safely move the fusb302_set_cc_pull
call to before setting TOGGLING_MODE_OFF.

Either we are not toggling yet, or the src-current has already been set,
so we can also safely set the src-current earlier, allowing us to do the
fusb302_set_toggling(TOGGLING_MODE_OFF) call at the same time as we
set the other toggling modes. Also setting the src-current is a no-op
when not enabling pull-ups, so we can drop the if.

And since the second fusb302_set_toggling undoes the effects of step 5,
we can skip step 5, the bc-lvl resp comp-chng irq wil be enabled by
fusb302_handle_togdone_snk resp. fusb302_handle_togdone_src when toggling
is done.

Together this allows us to simplify things to:

1) fusb302_set_cc_pull(...)
2) "reset cc status"
3) fusb302_set_src_current(...)
4) fusb302_set_toggling(new-toggling-mode)

This commit does this, leading to a nice cleanup.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 15:06:12 +01:00
..
altmodes usb: typec: altmodes/displayport: Fall back to multi-func pins 2019-03-19 15:00:34 +01:00
mux usb: typec: pi3usb30532: Keep orientation when setting mux to safe mode 2019-03-19 15:00:34 +01:00
tcpm usb: typec: fusb302: Refactor / simplify tcpm_set_cc() 2019-03-19 15:06:12 +01:00
ucsi usb: typec: ucsi: Remove debug.h file 2019-02-08 10:25:12 +01:00
bus.c usb/typec: fix kernel-doc notation warning for typec_match_altmode 2018-09-05 14:36:53 +02:00
bus.h usb: typec: avoid format-overflow warning 2018-07-06 16:36:19 +02:00
class.c usb: typec: Find the ports by also matching against the device node 2019-02-14 10:52:25 +01:00
Kconfig USB: add missing SPDX lines to Kconfig and Makefiles 2019-01-22 09:08:17 +01:00
Makefile usb: typec: Group all TCPCI/TCPM code together 2018-09-20 13:37:29 +02:00
mux.c usb: typec: mux: remove redundant check on variable match 2019-02-20 11:29:01 +01:00
tps6598x.c usb: typec: tps6598x: handle block writes separately with plain-I2C adapters 2019-02-21 10:54:23 +01:00