Commit daf81d01 authored by Hans de Goede's avatar Hans de Goede Committed by Greg Kroah-Hartman
Browse files

usb: typec: fusb302: Refactor / simplify tcpm_set_cc() 



After commit ea3b4d55 ("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: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Acked-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 31df7fad

drivers/usb/typec/tcpm/fusb302.c

+15 −70
Original line number Diff line number Diff line
@@ -676,7 +676,6 @@ static int tcpm_set_cc(struct tcpc_dev *dev, enum typec_cc_status cc) 
						 tcpc_dev);

	int ret = 0;

	bool pull_up, pull_down;

	u8 rd_mda;

	enum toggling_mode mode;



	mutex_lock(&chip->lock);
@@ -684,16 +683,19 @@ static int tcpm_set_cc(struct tcpc_dev *dev, enum typec_cc_status cc) 
	case TYPEC_CC_OPEN:

		pull_up = false;

		pull_down = false;

		mode = TOGGLING_MODE_OFF;

		break;

	case TYPEC_CC_RD:

		pull_up = false;

		pull_down = true;

		mode = TOGGLING_MODE_SNK;

		break;

	case TYPEC_CC_RP_DEF:

	case TYPEC_CC_RP_1_5:

	case TYPEC_CC_RP_3_0:

		pull_up = true;

		pull_down = false;

		mode = TOGGLING_MODE_SRC;

		break;

	default:

		fusb302_log(chip, "unsupported cc value %s",
@@ -701,11 +703,9 @@ static int tcpm_set_cc(struct tcpc_dev *dev, enum typec_cc_status cc) 
		ret = -EINVAL;

		goto done;

	}

	ret = fusb302_set_toggling(chip, TOGGLING_MODE_OFF);

	if (ret < 0) {

		fusb302_log(chip, "cannot stop toggling, ret=%d", ret);

		goto done;

	}



	fusb302_log(chip, "cc := %s", typec_cc_status_name[cc]);



	ret = fusb302_set_cc_pull(chip, pull_up, pull_down);

	if (ret < 0) {

		fusb302_log(chip,
@@ -718,74 +718,19 @@ static int tcpm_set_cc(struct tcpc_dev *dev, enum typec_cc_status cc) 
	/* reset the cc status */

	chip->cc1 = TYPEC_CC_OPEN;

	chip->cc2 = TYPEC_CC_OPEN;



	/* adjust current for SRC */

	if (pull_up) {

	ret = fusb302_set_src_current(chip, cc_src_current[cc]);

	if (ret < 0) {

		fusb302_log(chip, "cannot set src current %s, ret=%d",

			    typec_cc_status_name[cc], ret);

		goto done;

	}

	}

	/* enable/disable interrupts, BC_LVL for SNK and COMP_CHNG for SRC */

	if (pull_up) {

		rd_mda = rd_mda_value[cc_src_current[cc]];

		ret = fusb302_i2c_write(chip, FUSB_REG_MEASURE, rd_mda);

		if (ret < 0) {

			fusb302_log(chip,

				    "cannot set SRC measure value, ret=%d",

				    ret);

			goto done;

		}

		ret = fusb302_i2c_mask_write(chip, FUSB_REG_MASK,

					     FUSB_REG_MASK_BC_LVL |

					     FUSB_REG_MASK_COMP_CHNG,

					     FUSB_REG_MASK_COMP_CHNG);

		if (ret < 0) {

			fusb302_log(chip, "cannot set SRC interrupt, ret=%d",

				    ret);

			goto done;

		}

		chip->intr_bc_lvl = false;

		chip->intr_comp_chng = true;

	}

	if (pull_down) {

		ret = fusb302_i2c_mask_write(chip, FUSB_REG_MASK,

					     FUSB_REG_MASK_BC_LVL |

					     FUSB_REG_MASK_COMP_CHNG,

					     FUSB_REG_MASK_BC_LVL);

		if (ret < 0) {

			fusb302_log(chip, "cannot set SRC interrupt, ret=%d",

				    ret);

			goto done;

		}

		chip->intr_bc_lvl = true;

		chip->intr_comp_chng = false;

	}

	fusb302_log(chip, "cc := %s", typec_cc_status_name[cc]);



	/* Enable detection for fixed SNK or SRC only roles */

	switch (cc) {

	case TYPEC_CC_RD:

		mode = TOGGLING_MODE_SNK;

		break;

	case TYPEC_CC_RP_DEF:

	case TYPEC_CC_RP_1_5:

	case TYPEC_CC_RP_3_0:

		mode = TOGGLING_MODE_SRC;

		break;

	default:

		mode = TOGGLING_MODE_OFF;

		break;

	}



	if (mode != TOGGLING_MODE_OFF) {

	ret = fusb302_set_toggling(chip, mode);

	if (ret < 0)

			fusb302_log(chip,

				    "cannot set fixed role toggling mode, ret=%d",

				    ret);

	}

		fusb302_log(chip, "cannot set toggling mode, ret=%d", ret);



done:

	mutex_unlock(&chip->lock);