power: smb-lib: cache USB Type-C status

Currently the USB Type-C status is retrieved from the hardware in real
time. The Type-C change IRQ should trigger on every change of the Type-C
status, therefore it is not necessary to read the status registers
multiple times if a Type-C change IRQ has not triggered. Furthermore,
workarounds which force UFP/DFP mode, or disable Type-C altogether could
mislead the software into thinking a removal has happened.

Cache all of the USB Type-C status registers upon receiving a USB Type-C
change IRQ, and use the cached status where appropriate.

CRs-Fixed: 2020132
Change-Id: I99f2ff29633207898ae803672162db0c3cec80dc
Signed-off-by: Nicholas Troast <ntroast@codeaurora.org>
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>

2 files changed, 30 insertions, 86 deletions

diff --git a/drivers/power/supply/qcom/smb-lib.c b/drivers/power/supply/qcom/smb-lib.c
index c9fcb2be8569..f2fb6154e9e2 100644
--- a/drivers/power/supply/qcom/smb-lib.c
+++ b/drivers/power/supply/qcom/smb-lib.c
@@ -1145,7 +1145,7 @@ static int smblib_usb_irq_enable_vote_callback(struct votable *votable,
 static int _smblib_vconn_regulator_enable(struct regulator_dev *rdev)
 {
 	struct smb_charger *chg = rdev_get_drvdata(rdev);
-	u8 otg_stat, stat4;
+	u8 otg_stat, val;
 	int rc = 0, i;
 
 	if (!chg->external_vconn) {
@@ -1176,17 +1176,12 @@ static int _smblib_vconn_regulator_enable(struct regulator_dev *rdev)
 	 * VCONN_EN_ORIENTATION is overloaded with overriding the CC pin used
 	 * for Vconn, and it should be set with reverse polarity of CC_OUT.
 	 */
-	rc = smblib_read(chg, TYPE_C_STATUS_4_REG, &stat4);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_4 rc=%d\n", rc);
-		return rc;
-	}
-
 	smblib_dbg(chg, PR_OTG, "enabling VCONN\n");
-	stat4 = stat4 & CC_ORIENTATION_BIT ? 0 : VCONN_EN_ORIENTATION_BIT;
+	val = chg->typec_status[3] &
+			CC_ORIENTATION_BIT ? 0 : VCONN_EN_ORIENTATION_BIT;
 	rc = smblib_masked_write(chg, TYPE_C_INTRPT_ENB_SOFTWARE_CTRL_REG,
 				 VCONN_EN_VALUE_BIT | VCONN_EN_ORIENTATION_BIT,
-				 VCONN_EN_VALUE_BIT | stat4);
+				 VCONN_EN_VALUE_BIT | val);
 	if (rc < 0) {
 		smblib_err(chg, "Couldn't enable vconn setting rc=%d\n", rc);
 		return rc;
@@ -2147,23 +2142,13 @@ int smblib_get_prop_charger_temp_max(struct smb_charger *chg,
 int smblib_get_prop_typec_cc_orientation(struct smb_charger *chg,
 					 union power_supply_propval *val)
 {
-	int rc = 0;
-	u8 stat;
-
-	rc = smblib_read(chg, TYPE_C_STATUS_4_REG, &stat);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_4 rc=%d\n", rc);
-		return rc;
-	}
-	smblib_dbg(chg, PR_REGISTER, "TYPE_C_STATUS_4 = 0x%02x\n",
-		   stat);
-
-	if (stat & CC_ATTACHED_BIT)
-		val->intval = (bool)(stat & CC_ORIENTATION_BIT) + 1;
+	if (chg->typec_status[3] & CC_ATTACHED_BIT)
+		val->intval =
+			(bool)(chg->typec_status[3] & CC_ORIENTATION_BIT) + 1;
 	else
 		val->intval = 0;
 
-	return rc;
+	return 0;
 }
 
 static const char * const smblib_typec_mode_name[] = {
@@ -2181,17 +2166,7 @@ static const char * const smblib_typec_mode_name[] = {
 
 static int smblib_get_prop_ufp_mode(struct smb_charger *chg)
 {
-	int rc;
-	u8 stat;
-
-	rc = smblib_read(chg, TYPE_C_STATUS_1_REG, &stat);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_1 rc=%d\n", rc);
-		return POWER_SUPPLY_TYPEC_NONE;
-	}
-	smblib_dbg(chg, PR_REGISTER, "TYPE_C_STATUS_1 = 0x%02x\n", stat);
-
-	switch (stat) {
+	switch (chg->typec_status[0]) {
 	case 0:
 		return POWER_SUPPLY_TYPEC_NONE;
 	case UFP_TYPEC_RDSTD_BIT:
@@ -2209,17 +2184,7 @@ static int smblib_get_prop_ufp_mode(struct smb_charger *chg)
 
 static int smblib_get_prop_dfp_mode(struct smb_charger *chg)
 {
-	int rc;
-	u8 stat;
-
-	rc = smblib_read(chg, TYPE_C_STATUS_2_REG, &stat);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_2 rc=%d\n", rc);
-		return POWER_SUPPLY_TYPEC_NONE;
-	}
-	smblib_dbg(chg, PR_REGISTER, "TYPE_C_STATUS_2 = 0x%02x\n", stat);
-
-	switch (stat & DFP_TYPEC_MASK) {
+	switch (chg->typec_status[1] & DFP_TYPEC_MASK) {
 	case DFP_RA_RA_BIT:
 		return POWER_SUPPLY_TYPEC_SINK_AUDIO_ADAPTER;
 	case DFP_RD_RD_BIT:
@@ -2240,28 +2205,17 @@ static int smblib_get_prop_dfp_mode(struct smb_charger *chg)
 int smblib_get_prop_typec_mode(struct smb_charger *chg,
 			       union power_supply_propval *val)
 {
-	int rc;
-	u8 stat;
-
-	rc = smblib_read(chg, TYPE_C_STATUS_4_REG, &stat);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_4 rc=%d\n", rc);
+	if (!(chg->typec_status[3] & TYPEC_DEBOUNCE_DONE_STATUS_BIT)) {
 		val->intval = POWER_SUPPLY_TYPEC_NONE;
-		return rc;
-	}
-	smblib_dbg(chg, PR_REGISTER, "TYPE_C_STATUS_4 = 0x%02x\n", stat);
-
-	if (!(stat & TYPEC_DEBOUNCE_DONE_STATUS_BIT)) {
-		val->intval = POWER_SUPPLY_TYPEC_NONE;
-		return rc;
+		return 0;
 	}
 
-	if (stat & UFP_DFP_MODE_STATUS_BIT)
+	if (chg->typec_status[3] & UFP_DFP_MODE_STATUS_BIT)
 		val->intval = smblib_get_prop_dfp_mode(chg);
 	else
 		val->intval = smblib_get_prop_ufp_mode(chg);
 
-	return rc;
+	return 0;
 }
 
 int smblib_get_prop_typec_power_role(struct smb_charger *chg,
@@ -2549,18 +2503,11 @@ int smblib_set_prop_pd_active(struct smb_charger *chg,
 			      const union power_supply_propval *val)
 {
 	int rc;
-	u8 stat = 0;
 	bool orientation;
 
 	if (!get_effective_result(chg->pd_allowed_votable))
 		return -EINVAL;
 
-	rc = smblib_read(chg, TYPE_C_STATUS_4_REG, &stat);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_4 rc=%d\n", rc);
-		return rc;
-	}
-
 	chg->pd_active = val->intval;
 	if (chg->pd_active) {
 		vote(chg->apsd_disable_votable, PD_VOTER, true, 0);
@@ -2572,7 +2519,7 @@ int smblib_set_prop_pd_active(struct smb_charger *chg,
 		 * line when TYPEC_SPARE_CFG_BIT (CC pin selection s/w override)
 		 * is set or when VCONN_EN_VALUE_BIT is set.
 		 */
-		orientation = stat & CC_ORIENTATION_BIT;
+		orientation = chg->typec_status[3] & CC_ORIENTATION_BIT;
 		rc = smblib_masked_write(chg,
 				TYPE_C_INTRPT_ENB_SOFTWARE_CTRL_REG,
 				VCONN_EN_ORIENTATION_BIT,
@@ -2623,8 +2570,9 @@ int smblib_set_prop_pd_active(struct smb_charger *chg,
 			smblib_err(chg, "Couldn't enable HW cc_out rc=%d\n",
 									rc);
 
-		if ((stat & (TYPEC_DEBOUNCE_DONE_STATUS_BIT | UFP_DFP_MODE_BIT))
-					== TYPEC_DEBOUNCE_DONE_STATUS_BIT)
+		if ((chg->typec_status[3] &
+			(TYPEC_DEBOUNCE_DONE_STATUS_BIT | UFP_DFP_MODE_BIT))
+			== TYPEC_DEBOUNCE_DONE_STATUS_BIT)
 			try_rerun_apsd_for_hvdcp(chg);
 	}
 
@@ -3732,37 +3680,32 @@ irqreturn_t smblib_handle_usb_typec_change_for_uusb(struct smb_charger *chg)
 static void smblib_usb_typec_change(struct smb_charger *chg)
 {
 	int rc;
-	u8 stat4, stat5;
 	bool debounce_done, sink_attached, legacy_cable;
 
-	rc = smblib_read(chg, TYPE_C_STATUS_4_REG, &stat4);
+	rc = smblib_multibyte_read(chg, TYPE_C_STATUS_1_REG,
+							chg->typec_status, 5);
 	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_4 rc=%d\n", rc);
-		return;
-	}
-
-	rc = smblib_read(chg, TYPE_C_STATUS_5_REG, &stat5);
-	if (rc < 0) {
-		smblib_err(chg, "Couldn't read TYPE_C_STATUS_5 rc=%d\n", rc);
+		smblib_err(chg, "Couldn't cache USB Type-C status rc=%d\n", rc);
 		return;
 	}
 
-	debounce_done = (bool)(stat4 & TYPEC_DEBOUNCE_DONE_STATUS_BIT);
-	sink_attached = (bool)(stat4 & UFP_DFP_MODE_STATUS_BIT);
-	legacy_cable = (bool)(stat5 & TYPEC_LEGACY_CABLE_STATUS_BIT);
+	debounce_done =
+		(bool)(chg->typec_status[3] & TYPEC_DEBOUNCE_DONE_STATUS_BIT);
+	sink_attached =
+		(bool)(chg->typec_status[3] & UFP_DFP_MODE_STATUS_BIT);
+	legacy_cable =
+		(bool)(chg->typec_status[4] & TYPEC_LEGACY_CABLE_STATUS_BIT);
 
 	smblib_handle_typec_debounce_done(chg,
 			debounce_done, sink_attached, legacy_cable);
 
-	if (stat4 & TYPEC_VBUS_ERROR_STATUS_BIT)
+	if (chg->typec_status[3] & TYPEC_VBUS_ERROR_STATUS_BIT)
 		smblib_dbg(chg, PR_INTERRUPT, "IRQ: vbus-error\n");
 
-	if (stat4 & TYPEC_VCONN_OVERCURR_STATUS_BIT)
+	if (chg->typec_status[3] & TYPEC_VCONN_OVERCURR_STATUS_BIT)
 		schedule_work(&chg->vconn_oc_work);
 
 	power_supply_changed(chg->usb_psy);
-	smblib_dbg(chg, PR_REGISTER, "TYPE_C_STATUS_4 = 0x%02x\n", stat4);
-	smblib_dbg(chg, PR_REGISTER, "TYPE_C_STATUS_5 = 0x%02x\n", stat5);
 }
 
 irqreturn_t smblib_handle_usb_typec_change(int irq, void *data)
diff --git a/drivers/power/supply/qcom/smb-lib.h b/drivers/power/supply/qcom/smb-lib.h
index 877f62a77d1a..603628655567 100644
--- a/drivers/power/supply/qcom/smb-lib.h
+++ b/drivers/power/supply/qcom/smb-lib.h
@@ -309,6 +309,7 @@ struct smb_charger {
 	bool			uusb_apsd_rerun_done;
 	bool			pd_hard_reset;
 	bool			typec_present;
+	u8			typec_status[5];
 
 	/* workaround flag */
 	u32			wa_flags;