Commit 31df7fad authored by Hans de Goede's avatar Hans de Goede Committed by Greg Kroah-Hartman
Browse files

usb: typec: fusb302: Make fusb302_set_cc_polarity also set pull ups / downs 



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 the 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.

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 bfb2ab8e

drivers/usb/typec/tcpm/fusb302.c

+16 −32
Original line number Diff line number Diff line
@@ -99,7 +99,6 @@ struct fusb302_chip { 
	bool intr_comp_chng;



	/* port status */

	bool pull_up;

	bool vconn_on;

	bool vbus_on;

	bool charge_on;
@@ -540,7 +539,6 @@ static int fusb302_set_cc_pull(struct fusb302_chip *chip, 
				     mask, data);

	if (ret < 0)

		return ret;

	chip->pull_up = pull_up;



	return ret;

}
@@ -1226,38 +1224,36 @@ static const char * const cc_polarity_name[] = { 
	[TYPEC_POLARITY_CC2]	= "Polarity_CC2",

};



static int fusb302_set_cc_polarity(struct fusb302_chip *chip,

				   enum typec_cc_polarity cc_polarity)

static int fusb302_set_cc_polarity_and_pull(struct fusb302_chip *chip,

					    enum typec_cc_polarity cc_polarity,

					    bool pull_up, bool pull_down)

{

	int ret = 0;

	u8 switches0_mask = FUSB_REG_SWITCHES0_CC1_PU_EN |

			    FUSB_REG_SWITCHES0_CC2_PU_EN |

			    FUSB_REG_SWITCHES0_VCONN_CC1 |

			    FUSB_REG_SWITCHES0_VCONN_CC2 |

			    FUSB_REG_SWITCHES0_MEAS_CC1 |

			    FUSB_REG_SWITCHES0_MEAS_CC2;

	u8 switches0_data = 0x00;

	u8 switches1_mask = FUSB_REG_SWITCHES1_TXCC1_EN |

			    FUSB_REG_SWITCHES1_TXCC2_EN;

	u8 switches1_data = 0x00;



	if (pull_down)

		switches0_data |= FUSB_REG_SWITCHES0_CC1_PD_EN |

				  FUSB_REG_SWITCHES0_CC2_PD_EN;



	if (cc_polarity == TYPEC_POLARITY_CC1) {

		switches0_data = FUSB_REG_SWITCHES0_MEAS_CC1;

		switches0_data |= FUSB_REG_SWITCHES0_MEAS_CC1;

		if (chip->vconn_on)

			switches0_data |= FUSB_REG_SWITCHES0_VCONN_CC2;

		if (chip->pull_up)

		if (pull_up)

			switches0_data |= FUSB_REG_SWITCHES0_CC1_PU_EN;

		switches1_data = FUSB_REG_SWITCHES1_TXCC1_EN;

	} else {

		switches0_data = FUSB_REG_SWITCHES0_MEAS_CC2;

		switches0_data |= FUSB_REG_SWITCHES0_MEAS_CC2;

		if (chip->vconn_on)

			switches0_data |= FUSB_REG_SWITCHES0_VCONN_CC1;

		if (chip->pull_up)

		if (pull_up)

			switches0_data |= FUSB_REG_SWITCHES0_CC2_PU_EN;

		switches1_data = FUSB_REG_SWITCHES1_TXCC2_EN;

	}

	ret = fusb302_i2c_mask_write(chip, FUSB_REG_SWITCHES0,

				     switches0_mask, switches0_data);

	ret = fusb302_i2c_write(chip, FUSB_REG_SWITCHES0, switches0_data);

	if (ret < 0)

		return ret;

	ret = fusb302_i2c_mask_write(chip, FUSB_REG_SWITCHES1,
@@ -1278,16 +1274,10 @@ static int fusb302_handle_togdone_snk(struct fusb302_chip *chip, 
	enum typec_cc_polarity cc_polarity;

	enum typec_cc_status cc_status_active, cc1, cc2;



	/* set pull_up, pull_down */

	ret = fusb302_set_cc_pull(chip, false, true);

	if (ret < 0) {

		fusb302_log(chip, "cannot set cc to pull down, ret=%d", ret);

		return ret;

	}

	/* set polarity */

	/* set polarity and pull_up, pull_down */

	cc_polarity = (togdone_result == FUSB_REG_STATUS1A_TOGSS_SNK1) ?

		      TYPEC_POLARITY_CC1 : TYPEC_POLARITY_CC2;

	ret = fusb302_set_cc_polarity(chip, cc_polarity);

	ret = fusb302_set_cc_polarity_and_pull(chip, cc_polarity, false, true);

	if (ret < 0) {

		fusb302_log(chip, "cannot set cc polarity %s, ret=%d",

			    cc_polarity_name[cc_polarity], ret);
@@ -1354,16 +1344,10 @@ static int fusb302_handle_togdone_src(struct fusb302_chip *chip, 
	enum typec_cc_polarity cc_polarity;

	enum typec_cc_status cc_status_active, cc1, cc2;



	/* set pull_up, pull_down */

	ret = fusb302_set_cc_pull(chip, true, false);

	if (ret < 0) {

		fusb302_log(chip, "cannot set cc to pull up, ret=%d", ret);

		return ret;

	}

	/* set polarity */

	/* set polarity and pull_up, pull_down */

	cc_polarity = (togdone_result == FUSB_REG_STATUS1A_TOGSS_SRC1) ?

		      TYPEC_POLARITY_CC1 : TYPEC_POLARITY_CC2;

	ret = fusb302_set_cc_polarity(chip, cc_polarity);

	ret = fusb302_set_cc_polarity_and_pull(chip, cc_polarity, true, false);

	if (ret < 0) {

		fusb302_log(chip, "cannot set cc polarity %s, ret=%d",

			    cc_polarity_name[cc_polarity], ret);