ab8500_bm: Skip first CCEOC irq for instant current

When enabling the CCEOC irq we might get false interrupt
from ab8500-driver due to the latched value will be saved
and interpreted as an IRQ when enabled

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Johan Bjornstedt <johan.bjornstedt@stericsson.com>
Signed-off-by: Henrik Solver <henrik.solver@stericsson.com>
Reviewed-by: Karl KOMIEROWSKI <karl.komierowski@stericsson.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>

2 files changed, 59 insertions, 15 deletions

diff --git a/drivers/power/ab8500_btemp.c b/drivers/power/ab8500_btemp.c
index e1d28039ce7b..4a570b6c9e47 100644
--- a/drivers/power/ab8500_btemp.c
+++ b/drivers/power/ab8500_btemp.c
@@ -374,13 +374,10 @@ static int ab8500_btemp_get_batctrl_res(struct ab8500_btemp *di)
                 return ret;
         }
 
-        /*
-         * Since there is no interrupt when current measurement is done,
-         * loop for over 250ms (250ms is one sample conversion time
-         * with 32.768 Khz RTC clock). Note that a stop time must be set
-         * since the ab8500_btemp_read_batctrl_voltage call can block and
-         * take an unknown amount of time to complete.
-         */
+        do {
+                msleep(20);
+        } while (!ab8500_fg_inst_curr_started(di->fg));
+
         i = 0;
 
         do {
diff --git a/drivers/power/ab8500_fg.c b/drivers/power/ab8500_fg.c
index 3d05c73813c8..0f40c968286c 100644
--- a/drivers/power/ab8500_fg.c
+++ b/drivers/power/ab8500_fg.c
@@ -160,6 +160,7 @@ struct inst_curr_result_list {
  * @recovery_cnt:       Counter for recovery mode
  * @high_curr_cnt:      Counter for high current mode
  * @init_cnt:           Counter for init mode
+ * @nbr_cceoc_irq_cnt   Counter for number of CCEOC irqs received since enabled
  * @recovery_needed:    Indicate if recovery is needed
  * @high_curr_mode:     Indicate if we're in high current mode
  * @init_capacity:      Indicate if initial capacity measuring should be done
@@ -167,6 +168,7 @@ struct inst_curr_result_list {
  * @calib_state         State during offset calibration
  * @discharge_state:    Current discharge state
  * @charge_state:       Current charge state
+ * @ab8500_fg_started   Completion struct used for the instant current start
  * @ab8500_fg_complete  Completion struct used for the instant current reading
  * @flags:              Structure for information about events triggered
  * @bat_cap:            Structure for battery capacity specific parameters
@@ -199,6 +201,7 @@ struct ab8500_fg {
         int recovery_cnt;
         int high_curr_cnt;
         int init_cnt;
+        int nbr_cceoc_irq_cnt;
         bool recovery_needed;
         bool high_curr_mode;
         bool init_capacity;
@@ -206,6 +209,7 @@ struct ab8500_fg {
         enum ab8500_fg_calibration_state calib_state;
         enum ab8500_fg_discharge_state discharge_state;
         enum ab8500_fg_charge_state charge_state;
+        struct completion ab8500_fg_started;
         struct completion ab8500_fg_complete;
         struct ab8500_fg_flags flags;
         struct ab8500_fg_battery_capacity bat_cap;
@@ -524,13 +528,14 @@ cc_err:
  * Note: This is part "one" and has to be called before
  * ab8500_fg_inst_curr_finalize()
  */
- int ab8500_fg_inst_curr_start(struct ab8500_fg *di)
+int ab8500_fg_inst_curr_start(struct ab8500_fg *di)
 {
         u8 reg_val;
         int ret;
 
         mutex_lock(&di->cc_lock);
 
+        di->nbr_cceoc_irq_cnt = 0;
         ret = abx500_get_register_interruptible(di->dev, AB8500_RTC,
                 AB8500_RTC_CC_CONF_REG, &reg_val);
         if (ret < 0)
@@ -558,6 +563,7 @@ cc_err:
         }
 
         /* Return and WFI */
+        INIT_COMPLETION(di->ab8500_fg_started);
         INIT_COMPLETION(di->ab8500_fg_complete);
         enable_irq(di->irq);
 
@@ -569,6 +575,17 @@ fail:
 }
 
 /**
+ * ab8500_fg_inst_curr_started() - check if fg conversion has started
+ * @di:         pointer to the ab8500_fg structure
+ *
+ * Returns 1 if conversion started, 0 if still waiting
+ */
+int ab8500_fg_inst_curr_started(struct ab8500_fg *di)
+{
+        return completion_done(&di->ab8500_fg_started);
+}
+
+/**
  * ab8500_fg_inst_curr_done() - check if fg conversion is done
  * @di:         pointer to the ab8500_fg structure
  *
@@ -596,13 +613,15 @@ int ab8500_fg_inst_curr_finalize(struct ab8500_fg *di, int *res)
         int timeout;
 
         if (!completion_done(&di->ab8500_fg_complete)) {
-                timeout = wait_for_completion_timeout(&di->ab8500_fg_complete,
+                timeout = wait_for_completion_timeout(
+                        &di->ab8500_fg_complete,
                         INS_CURR_TIMEOUT);
                 dev_dbg(di->dev, "Finalize time: %d ms\n",
                         ((INS_CURR_TIMEOUT - timeout) * 1000) / HZ);
                 if (!timeout) {
                         ret = -ETIME;
                         disable_irq(di->irq);
+                        di->nbr_cceoc_irq_cnt = 0;
                         dev_err(di->dev, "completion timed out [%d]\n",
                                 __LINE__);
                         goto fail;
@@ -610,6 +629,7 @@ int ab8500_fg_inst_curr_finalize(struct ab8500_fg *di, int *res)
         }
 
         disable_irq(di->irq);
+        di->nbr_cceoc_irq_cnt = 0;
 
         ret = abx500_mask_and_set_register_interruptible(di->dev,
                         AB8500_GAS_GAUGE, AB8500_GASG_CC_CTRL_REG,
@@ -684,6 +704,7 @@ fail:
 int ab8500_fg_inst_curr_blocking(struct ab8500_fg *di)
 {
         int ret;
+        int timeout;
         int res = 0;
 
         ret = ab8500_fg_inst_curr_start(di);
@@ -692,13 +713,32 @@ int ab8500_fg_inst_curr_blocking(struct ab8500_fg *di)
                 return 0;
         }
 
+        /* Wait for CC to actually start */
+        if (!completion_done(&di->ab8500_fg_started)) {
+                timeout = wait_for_completion_timeout(
+                        &di->ab8500_fg_started,
+                        INS_CURR_TIMEOUT);
+                dev_dbg(di->dev, "Start time: %d ms\n",
+                        ((INS_CURR_TIMEOUT - timeout) * 1000) / HZ);
+                if (!timeout) {
+                        ret = -ETIME;
+                        dev_err(di->dev, "completion timed out [%d]\n",
+                                __LINE__);
+                        goto fail;
+                }
+        }
+
         ret = ab8500_fg_inst_curr_finalize(di, &res);
         if (ret) {
                 dev_err(di->dev, "Failed to finalize fg_inst\n");
                 return 0;
         }
 
+        dev_dbg(di->dev, "%s instant current: %d", __func__, res);
         return res;
+fail:
+        mutex_unlock(&di->cc_lock);
+        return ret;
 }
 
 /**
@@ -1523,8 +1563,6 @@ static void ab8500_fg_algorithm_discharging(struct ab8500_fg *di)
 
         case AB8500_FG_DISCHARGE_WAKEUP:
                 ab8500_fg_coulomb_counter(di, true);
-                di->inst_curr = ab8500_fg_inst_curr_blocking(di);
-
                 ab8500_fg_calc_cap_discharge_voltage(di, true);
 
                 di->fg_samples = SEC_TO_SAMPLE(
@@ -1641,8 +1679,6 @@ static void ab8500_fg_periodic_work(struct work_struct *work)
                 fg_periodic_work.work);
 
         if (di->init_capacity) {
-                /* A dummy read that will return 0 */
-                di->inst_curr = ab8500_fg_inst_curr_blocking(di);
                 /* Get an initial capacity calculation */
                 ab8500_fg_calc_cap_discharge_voltage(di, true);
                 ab8500_fg_check_capacity_limits(di, true);
@@ -1828,7 +1864,13 @@ static void ab8500_fg_instant_work(struct work_struct *work)
 static irqreturn_t ab8500_fg_cc_data_end_handler(int irq, void *_di)
 {
         struct ab8500_fg *di = _di;
-        complete(&di->ab8500_fg_complete);
+        if (!di->nbr_cceoc_irq_cnt) {
+                di->nbr_cceoc_irq_cnt++;
+                complete(&di->ab8500_fg_started);
+        } else {
+                di->nbr_cceoc_irq_cnt = 0;
+                complete(&di->ab8500_fg_complete);
+        }
         return IRQ_HANDLED;
 }
 
@@ -2551,7 +2593,11 @@ static int ab8500_fg_probe(struct platform_device *pdev)
         di->fg_samples = SEC_TO_SAMPLE(di->bm->fg_params->init_timer);
         ab8500_fg_coulomb_counter(di, true);
 
-        /* Initialize completion used to notify completion of inst current */
+        /*
+         * Initialize completion used to notify completion and start
+         * of inst current
+         */
+        init_completion(&di->ab8500_fg_started);
         init_completion(&di->ab8500_fg_complete);
 
         /* Register interrupts */
@@ -2571,6 +2617,7 @@ static int ab8500_fg_probe(struct platform_device *pdev)
         }
         di->irq = platform_get_irq_byname(pdev, "CCEOC");
         disable_irq(di->irq);
+        di->nbr_cceoc_irq_cnt = 0;
 
         platform_set_drvdata(pdev, di);