Commit 57ce6466 authored by Badhri Jagan Sridharan's avatar Badhri Jagan Sridharan Committed by Greg Kroah-Hartman
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usb: typec: tcpci: update ROLE_CONTROL for DRP



ROLE_CONTROL register would not have the actual CC terminations
unless the port does not set ROLE_CONTROL.DRP. For DRP ports,
CC_STATUS.cc1/cc2 indicates the final terminations applied
when TCPC enters potential_connect_as_source/_sink.
For DRP ports, infer port role from CC_STATUS and set corresponding
CC terminations before setting the orientation.

Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarBadhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20200901025927.3596190-4-badhri@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 19b65476
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+36 −1
Original line number Diff line number Diff line
@@ -191,12 +191,47 @@ static int tcpci_set_polarity(struct tcpc_dev *tcpc,
	struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
	unsigned int reg;
	int ret;
	enum typec_cc_status cc1, cc2;

	/* Keep the disconnect cc line open */
	/* Obtain Rp setting from role control */
	ret = regmap_read(tcpci->regmap, TCPC_ROLE_CTRL, &reg);
	if (ret < 0)
		return ret;

	ret = tcpci_get_cc(tcpc, &cc1, &cc2);
	if (ret < 0)
		return ret;

	/*
	 * When port has drp toggling enabled, ROLE_CONTROL would only have the initial
	 * terminations for the toggling and does not indicate the final cc
	 * terminations when ConnectionResult is 0 i.e. drp toggling stops and
	 * the connection is resolbed. Infer port role from TCPC_CC_STATUS based on the
	 * terminations seen. The port role is then used to set the cc terminations.
	 */
	if (reg & TCPC_ROLE_CTRL_DRP) {
		/* Disable DRP for the OPEN setting to take effect */
		reg = reg & ~TCPC_ROLE_CTRL_DRP;

		if (polarity == TYPEC_POLARITY_CC2) {
			reg &= ~(TCPC_ROLE_CTRL_CC2_MASK << TCPC_ROLE_CTRL_CC2_SHIFT);
			/* Local port is source */
			if (cc2 == TYPEC_CC_RD)
				/* Role control would have the Rp setting when DRP was enabled */
				reg |= TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC2_SHIFT;
			else
				reg |= TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC2_SHIFT;
		} else {
			reg &= ~(TCPC_ROLE_CTRL_CC1_MASK << TCPC_ROLE_CTRL_CC1_SHIFT);
			/* Local port is source */
			if (cc1 == TYPEC_CC_RD)
				/* Role control would have the Rp setting when DRP was enabled */
				reg |= TCPC_ROLE_CTRL_CC_RP << TCPC_ROLE_CTRL_CC1_SHIFT;
			else
				reg |= TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC1_SHIFT;
		}
	}

	if (polarity == TYPEC_POLARITY_CC2)
		reg |= TCPC_ROLE_CTRL_CC_OPEN << TCPC_ROLE_CTRL_CC1_SHIFT;
	else