power: smb-lib: Add support to detect weak charger

A weak charger might trigger switcher_power_ok interrupt storm
which gets incorrectly detected as a boost_back condition and
input gets suspended. Add a logic to distinguish a weak charger
and the boost_back condition by first reducing the ICL current
to a lower value (500mA by default) on detecting a
switcher_power_ok storm. If the switcher_ok storm disappears
then its indeed a weak charger and if the storm continues its
possibly a boost_back condition.

Change-Id: I46b406e403aa16a502e6da149b180545848fc906
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>

5 files changed, 102 insertions, 19 deletions

diff --git a/drivers/power/supply/qcom/qpnp-smb2.c b/drivers/power/supply/qcom/qpnp-smb2.c
index 803851d2b3ef..49cd7aa6fdac 100644
--- a/drivers/power/supply/qcom/qpnp-smb2.c
+++ b/drivers/power/supply/qcom/qpnp-smb2.c
@@ -266,6 +266,10 @@ module_param_named(
 	debug_mask, __debug_mask, int, S_IRUSR | S_IWUSR
 );
 
+static int __weak_chg_icl_ua = 500000;
+module_param_named(
+	weak_chg_icl_ua, __weak_chg_icl_ua, int, S_IRUSR | S_IWUSR);
+
 #define MICRO_1P5A		1500000
 #define MICRO_P1A		100000
 #define OTG_DEFAULT_DEGLITCH_TIME_MS	50
@@ -2109,7 +2113,7 @@ static struct smb_irq_info smb2_irqs[] = {
 	[SWITCH_POWER_OK_IRQ] = {
 		.name		= "switcher-power-ok",
 		.handler	= smblib_handle_switcher_power_ok,
-		.storm_data	= {true, 1000, 3},
+		.storm_data	= {true, 1000, 8},
 	},
 };
 
@@ -2303,6 +2307,7 @@ static int smb2_probe(struct platform_device *pdev)
 	chg->dev = &pdev->dev;
 	chg->param = v1_params;
 	chg->debug_mask = &__debug_mask;
+	chg->weak_chg_icl_ua = &__weak_chg_icl_ua;
 	chg->mode = PARALLEL_MASTER;
 	chg->irq_info = smb2_irqs;
 	chg->name = "PMI";
diff --git a/drivers/power/supply/qcom/smb-lib.c b/drivers/power/supply/qcom/smb-lib.c
index 49a5a17a521b..22944f122c44 100644
--- a/drivers/power/supply/qcom/smb-lib.c
+++ b/drivers/power/supply/qcom/smb-lib.c
@@ -630,6 +630,8 @@ int smblib_mapping_cc_delta_from_field_value(struct smb_chg_param *param,
 static void smblib_uusb_removal(struct smb_charger *chg)
 {
 	int rc;
+	struct smb_irq_data *data;
+	struct storm_watch *wdata;
 
 	cancel_delayed_work_sync(&chg->pl_enable_work);
 
@@ -641,8 +643,16 @@ static void smblib_uusb_removal(struct smb_charger *chg)
 				rc);
 	}
 
-	if (chg->wa_flags & BOOST_BACK_WA)
-		vote(chg->usb_icl_votable, BOOST_BACK_VOTER, false, 0);
+	if (chg->wa_flags & BOOST_BACK_WA) {
+		data = chg->irq_info[SWITCH_POWER_OK_IRQ].irq_data;
+		if (data) {
+			wdata = &data->storm_data;
+			update_storm_count(wdata, WEAK_CHG_STORM_COUNT);
+			vote(chg->usb_icl_votable, BOOST_BACK_VOTER, false, 0);
+			vote(chg->usb_icl_votable, WEAK_CHARGER_VOTER,
+					false, 0);
+		}
+	}
 	vote(chg->pl_disable_votable, PL_DELAY_VOTER, true, 0);
 	vote(chg->awake_votable, PL_DELAY_VOTER, false, 0);
 
@@ -3138,6 +3148,8 @@ void smblib_usb_plugin_hard_reset_locked(struct smb_charger *chg)
 	int rc;
 	u8 stat;
 	bool vbus_rising;
+	struct smb_irq_data *data;
+	struct storm_watch *wdata;
 
 	rc = smblib_read(chg, USBIN_BASE + INT_RT_STS_OFFSET, &stat);
 	if (rc < 0) {
@@ -3151,8 +3163,18 @@ void smblib_usb_plugin_hard_reset_locked(struct smb_charger *chg)
 		smblib_cc2_sink_removal_exit(chg);
 	} else {
 		smblib_cc2_sink_removal_enter(chg);
-		if (chg->wa_flags & BOOST_BACK_WA)
-			vote(chg->usb_icl_votable, BOOST_BACK_VOTER, false, 0);
+		if (chg->wa_flags & BOOST_BACK_WA) {
+			data = chg->irq_info[SWITCH_POWER_OK_IRQ].irq_data;
+			if (data) {
+				wdata = &data->storm_data;
+				update_storm_count(wdata,
+						WEAK_CHG_STORM_COUNT);
+				vote(chg->usb_icl_votable, BOOST_BACK_VOTER,
+						false, 0);
+				vote(chg->usb_icl_votable, WEAK_CHARGER_VOTER,
+						false, 0);
+			}
+		}
 	}
 
 	power_supply_changed(chg->usb_psy);
@@ -3166,6 +3188,8 @@ void smblib_usb_plugin_locked(struct smb_charger *chg)
 	int rc;
 	u8 stat;
 	bool vbus_rising;
+	struct smb_irq_data *data;
+	struct storm_watch *wdata;
 
 	rc = smblib_read(chg, USBIN_BASE + INT_RT_STS_OFFSET, &stat);
 	if (rc < 0) {
@@ -3202,8 +3226,18 @@ void smblib_usb_plugin_locked(struct smb_charger *chg)
 		schedule_delayed_work(&chg->pl_enable_work,
 					msecs_to_jiffies(PL_DELAY_MS));
 	} else {
-		if (chg->wa_flags & BOOST_BACK_WA)
-			vote(chg->usb_icl_votable, BOOST_BACK_VOTER, false, 0);
+		if (chg->wa_flags & BOOST_BACK_WA) {
+			data = chg->irq_info[SWITCH_POWER_OK_IRQ].irq_data;
+			if (data) {
+				wdata = &data->storm_data;
+				update_storm_count(wdata,
+						WEAK_CHG_STORM_COUNT);
+				vote(chg->usb_icl_votable, BOOST_BACK_VOTER,
+						false, 0);
+				vote(chg->usb_icl_votable, WEAK_CHARGER_VOTER,
+						false, 0);
+			}
+		}
 
 		if (chg->dpdm_reg && regulator_is_enabled(chg->dpdm_reg)) {
 			smblib_dbg(chg, PR_MISC, "disabling DPDM regulator\n");
@@ -3582,6 +3616,8 @@ static void typec_sink_removal(struct smb_charger *chg)
 static void smblib_handle_typec_removal(struct smb_charger *chg)
 {
 	int rc;
+	struct smb_irq_data *data;
+	struct storm_watch *wdata;
 
 	chg->cc2_detach_wa_active = false;
 
@@ -3593,8 +3629,16 @@ static void smblib_handle_typec_removal(struct smb_charger *chg)
 				rc);
 	}
 
-	if (chg->wa_flags & BOOST_BACK_WA)
-		vote(chg->usb_icl_votable, BOOST_BACK_VOTER, false, 0);
+	if (chg->wa_flags & BOOST_BACK_WA) {
+		data = chg->irq_info[SWITCH_POWER_OK_IRQ].irq_data;
+		if (data) {
+			wdata = &data->storm_data;
+			update_storm_count(wdata, WEAK_CHG_STORM_COUNT);
+			vote(chg->usb_icl_votable, BOOST_BACK_VOTER, false, 0);
+			vote(chg->usb_icl_votable, WEAK_CHARGER_VOTER,
+					false, 0);
+		}
+	}
 
 	/* reset APSD voters */
 	vote(chg->apsd_disable_votable, PD_HARD_RESET_VOTER, false, 0);
@@ -3826,10 +3870,13 @@ static void smblib_bb_removal_work(struct work_struct *work)
 }
 
 #define BOOST_BACK_UNVOTE_DELAY_MS		750
+#define BOOST_BACK_STORM_COUNT			3
+#define WEAK_CHG_STORM_COUNT			8
 irqreturn_t smblib_handle_switcher_power_ok(int irq, void *data)
 {
 	struct smb_irq_data *irq_data = data;
 	struct smb_charger *chg = irq_data->parent_data;
+	struct storm_watch *wdata = &irq_data->storm_data;
 	int rc, usb_icl;
 	u8 stat;
 
@@ -3851,16 +3898,32 @@ irqreturn_t smblib_handle_switcher_power_ok(int irq, void *data)
 		return IRQ_HANDLED;
 
 	if (is_storming(&irq_data->storm_data)) {
-		smblib_err(chg, "Reverse boost detected: voting 0mA to suspend input\n");
-		vote(chg->usb_icl_votable, BOOST_BACK_VOTER, true, 0);
-		vote(chg->awake_votable, BOOST_BACK_VOTER, true, 0);
-		/*
-		 * Remove the boost-back vote after a delay, to avoid
-		 * permanently suspending the input if the boost-back condition
-		 * is unintentionally hit.
-		 */
-		schedule_delayed_work(&chg->bb_removal_work,
-			msecs_to_jiffies(BOOST_BACK_UNVOTE_DELAY_MS));
+		/* This could be a weak charger reduce ICL */
+		if (!is_client_vote_enabled(chg->usb_icl_votable,
+						WEAK_CHARGER_VOTER)) {
+			smblib_err(chg,
+				"Weak charger detected: voting %dmA ICL\n",
+				*chg->weak_chg_icl_ua / 1000);
+			vote(chg->usb_icl_votable, WEAK_CHARGER_VOTER,
+					true, *chg->weak_chg_icl_ua);
+			/*
+			 * reset storm data and set the storm threshold
+			 * to 3 for reverse boost detection.
+			 */
+			update_storm_count(wdata, BOOST_BACK_STORM_COUNT);
+		} else {
+			smblib_err(chg,
+				"Reverse boost detected: voting 0mA to suspend input\n");
+			vote(chg->usb_icl_votable, BOOST_BACK_VOTER, true, 0);
+			vote(chg->awake_votable, BOOST_BACK_VOTER, true, 0);
+			/*
+			 * Remove the boost-back vote after a delay, to avoid
+			 * permanently suspending the input if the boost-back
+			 * condition is unintentionally hit.
+			 */
+			schedule_delayed_work(&chg->bb_removal_work,
+				msecs_to_jiffies(BOOST_BACK_UNVOTE_DELAY_MS));
+		}
 	}
 
 	return IRQ_HANDLED;
diff --git a/drivers/power/supply/qcom/smb-lib.h b/drivers/power/supply/qcom/smb-lib.h
index a428b35f9493..c97b84c34084 100644
--- a/drivers/power/supply/qcom/smb-lib.h
+++ b/drivers/power/supply/qcom/smb-lib.h
@@ -64,9 +64,12 @@ enum print_reason {
 #define BATT_PROFILE_VOTER		"BATT_PROFILE_VOTER"
 #define OTG_DELAY_VOTER			"OTG_DELAY_VOTER"
 #define USBIN_I_VOTER			"USBIN_I_VOTER"
+#define WEAK_CHARGER_VOTER		"WEAK_CHARGER_VOTER"
 
 #define VCONN_MAX_ATTEMPTS	3
 #define OTG_MAX_ATTEMPTS	3
+#define BOOST_BACK_STORM_COUNT	3
+#define WEAK_CHG_STORM_COUNT	8
 
 enum smb_mode {
 	PARALLEL_MASTER = 0,
@@ -230,6 +233,7 @@ struct smb_charger {
 	struct smb_chg_freq	chg_freq;
 	int			smb_version;
 	int			otg_delay_ms;
+	int			*weak_chg_icl_ua;
 
 	/* locks */
 	struct mutex		lock;
diff --git a/drivers/power/supply/qcom/storm-watch.c b/drivers/power/supply/qcom/storm-watch.c
index 5275079c53e0..21ac669f2ec9 100644
--- a/drivers/power/supply/qcom/storm-watch.c
+++ b/drivers/power/supply/qcom/storm-watch.c
@@ -64,3 +64,13 @@ void reset_storm_count(struct storm_watch *data)
 	data->storm_count = 0;
 	mutex_unlock(&data->storm_lock);
 }
+
+void update_storm_count(struct storm_watch *data, int max_count)
+{
+	if (!data)
+		return;
+
+	mutex_lock(&data->storm_lock);
+	data->max_storm_count = max_count;
+	mutex_unlock(&data->storm_lock);
+}
diff --git a/drivers/power/supply/qcom/storm-watch.h b/drivers/power/supply/qcom/storm-watch.h
index ff05c4a661c3..5275d73613d4 100644
--- a/drivers/power/supply/qcom/storm-watch.h
+++ b/drivers/power/supply/qcom/storm-watch.h
@@ -37,4 +37,5 @@ struct storm_watch {
 
 bool is_storming(struct storm_watch *data);
 void reset_storm_count(struct storm_watch *data);
+void update_storm_count(struct storm_watch *data, int max_count);
 #endif