power: qcom-charger: add support to detect parallel charger

Add support to detect presence of parallel charger chip by
requesting a register read via power_supply framework.
If parallel chip is absent then disable parallel charger.

Change-Id: Icfa4a774d344fde4c7d1f4ced772a707be85020d
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>

diff --git a/drivers/power/supply/qcom/battery.c b/drivers/power/supply/qcom/battery.c
index 34add97..86e1bc0 100644 (file)
--- a/drivers/power/supply/qcom/battery.c
+++ b/drivers/power/supply/qcom/battery.c
@@ -33,6 +33,7 @@
 #define TAPER_END_VOTER                        "TAPER_END_VOTER"
 #define PL_TAPER_EARLY_BAD_VOTER       "PL_TAPER_EARLY_BAD_VOTER"
 #define PARALLEL_PSY_VOTER             "PARALLEL_PSY_VOTER"
+#define PL_HW_ABSENT_VOTER             "PL_HW_ABSENT_VOTER"
 
 struct pl_data {
        int                     pl_mode;
@@ -44,6 +45,7 @@ struct pl_data {
        struct votable          *pl_disable_votable;
        struct votable          *pl_awake_votable;
        struct work_struct      status_change_work;
+       struct work_struct      pl_disable_forever_work;
        struct delayed_work     pl_taper_work;
        struct power_supply     *main_psy;
        struct power_supply     *pl_psy;
@@ -361,6 +363,15 @@ static int pl_fv_vote_callback(struct votable *votable, void *data,
        return 0;
 }
 
+static void pl_disable_forever_work(struct work_struct *work)
+{
+       struct pl_data *chip = container_of(work,
+                       struct pl_data, pl_disable_forever_work);
+
+       /* Disable Parallel charger forever */
+       vote(chip->pl_disable_votable, PL_HW_ABSENT_VOTER, true, 0);
+}
+
 static int pl_disable_vote_callback(struct votable *votable,
                void *data, int pl_disable, const char *client)
 {
@@ -372,6 +383,18 @@ static int pl_disable_vote_callback(struct votable *votable,
        chip->taper_pct = 100;
 
        if (!pl_disable) { /* enable */
+               rc = power_supply_get_property(chip->pl_psy,
+                               POWER_SUPPLY_PROP_CHARGE_TYPE, &pval);
+               if (rc == -ENODEV) {
+                       /*
+                        * -ENODEV is returned only if parallel chip
+                        * is not present in the system.
+                        * Disable parallel charger forever.
+                        */
+                       schedule_work(&chip->pl_disable_forever_work);
+                       return rc;
+               }
+
                rerun_election(chip->fv_votable);
                rerun_election(chip->fcc_votable);
                /*
@@ -697,6 +720,7 @@ static int pl_init(void)
 
        INIT_WORK(&chip->status_change_work, status_change_work);
        INIT_DELAYED_WORK(&chip->pl_taper_work, pl_taper_work);
+       INIT_WORK(&chip->pl_disable_forever_work, pl_disable_forever_work);
 
        rc = pl_register_notifier(chip);
        if (rc < 0) {