asoc: wcd9xxx-core: avoid slimbus read/write during ADSP SSR

This reverts commit 40bc50d768038c04f8c1 ("mfd: wcd9xxx-core:
Synchronize codec down and reset calls from slimbus.").
This is to make sure that the dev_up flag is set right
after device_down is called from Slimbus after ADSP SSR.
This flag helps make sure that all read/write calls over
slimbus are blocked until ADSP and Slimbus are fully up
post-SSR.

Change-Id: I5595a23a0b51f2ca392ddfb5773b057204185b54
Signed-off-by: Banajit Goswami <[email protected]>

asoc/codecs/core.h

@@ -350,7 +350,7 @@ struct wcd9xxx {
 	int (*post_reset)(struct wcd9xxx *wcd9xxx);
 
 	void *ssr_priv;
-	unsigned long dev_up;
+	bool dev_up;
 
 	u32 num_of_supplies;
 	struct regulator_bulk_data *supplies;

asoc/codecs/wcd9xxx-core.c

@@ -228,7 +228,7 @@ static int wcd9xxx_slim_read_device(struct wcd9xxx *wcd9xxx, unsigned short reg,
 
 	if (!wcd9xxx->dev_up) {
 		dev_dbg_ratelimited(
-			wcd9xxx->dev, "%s: No read allowed. dev_up = %lu\n",
+			wcd9xxx->dev, "%s: No read allowed. dev_up = %d\n",
 			__func__, wcd9xxx->dev_up);
 		return 0;
 	}
@@ -268,7 +268,7 @@ static int wcd9xxx_slim_write_device(struct wcd9xxx *wcd9xxx,
 
 	if (!wcd9xxx->dev_up) {
 		dev_dbg_ratelimited(
-			wcd9xxx->dev, "%s: No write allowed. dev_up = %lu\n",
+			wcd9xxx->dev, "%s: No write allowed. dev_up = %d\n",
 			__func__, wcd9xxx->dev_up);
 		return 0;
 	}
@@ -345,7 +345,7 @@ int wcd9xxx_slim_write_repeat(struct wcd9xxx *wcd9xxx, unsigned short reg,
 
 	if (!wcd9xxx->dev_up) {
 		dev_dbg_ratelimited(
-			wcd9xxx->dev, "%s: No write allowed. dev_up = %lu\n",
+			wcd9xxx->dev, "%s: No write allowed. dev_up = %d\n",
 			__func__, wcd9xxx->dev_up);
 		ret = 0;
 		goto done;
@@ -426,7 +426,7 @@ int wcd9xxx_slim_bulk_write(struct wcd9xxx *wcd9xxx,
 
 	if (!wcd9xxx->dev_up) {
 		dev_dbg_ratelimited(
-			wcd9xxx->dev, "%s: No write allowed. dev_up = %lu\n",
+			wcd9xxx->dev, "%s: No write allowed. dev_up = %d\n",
 			__func__, wcd9xxx->dev_up);
 		return 0;
 	}
@@ -1484,27 +1484,12 @@ static int wcd9xxx_slim_device_reset(struct slim_device *sldev)
 		return -EINVAL;
 	}
 
-	/*
-	 * Wait for 500 ms for device down to complete. Observed delay
-	 *  of ~200ms for device down to complete after being called,
-	 * due to context switch issue.
-	 */
-	ret = wait_on_bit_timeout(&wcd9xxx->dev_up, 0,
-				  TASK_INTERRUPTIBLE,
-				  msecs_to_jiffies(500));
-	if (ret)
-		pr_err("%s: slim device down not complete in 500 msec\n",
-				__func__);
-
-	mutex_lock(&wcd9xxx->reset_lock);
-
-	dev_info(wcd9xxx->dev, "%s: device reset, dev_up = %lu\n",
-			__func__, wcd9xxx->dev_up);
-	if (wcd9xxx->dev_up) {
-		mutex_unlock(&wcd9xxx->reset_lock);
+	dev_info(wcd9xxx->dev, "%s: device reset, dev_up = %d\n",
+		__func__, wcd9xxx->dev_up);
+	if (wcd9xxx->dev_up)
 		return 0;
-	}
 
+	mutex_lock(&wcd9xxx->reset_lock);
 	ret = wcd9xxx_reset(wcd9xxx->dev);
 	if (ret)
 		dev_err(wcd9xxx->dev, "%s: Resetting Codec failed\n", __func__);
@@ -1522,8 +1507,8 @@ static int wcd9xxx_slim_device_up(struct slim_device *sldev)
 		pr_err("%s: wcd9xxx is NULL\n", __func__);
 		return -EINVAL;
 	}
-	dev_info(wcd9xxx->dev, "%s: slim device up, dev_up = %lu\n",
-			__func__, wcd9xxx->dev_up);
+	dev_info(wcd9xxx->dev, "%s: slim device up, dev_up = %d\n",
+		__func__, wcd9xxx->dev_up);
 	if (wcd9xxx->dev_up)
 		return 0;
 
@@ -1545,20 +1530,18 @@ static int wcd9xxx_slim_device_down(struct slim_device *sldev)
 		return -EINVAL;
 	}
 
-	mutex_lock(&wcd9xxx->reset_lock);
-
-	dev_info(wcd9xxx->dev, "%s: device down, dev_up = %lu\n",
-			__func__, wcd9xxx->dev_up);
-	if (!wcd9xxx->dev_up) {
-		mutex_unlock(&wcd9xxx->reset_lock);
+	dev_info(wcd9xxx->dev, "%s: device down, dev_up = %d\n",
+		__func__, wcd9xxx->dev_up);
+	if (!wcd9xxx->dev_up)
 		return 0;
-	}
 
+	wcd9xxx->dev_up = false;
+
+	mutex_lock(&wcd9xxx->reset_lock);
 	if (wcd9xxx->dev_down)
 		wcd9xxx->dev_down(wcd9xxx);
 	wcd9xxx_irq_exit(&wcd9xxx->core_res);
 	wcd9xxx_reset_low(wcd9xxx->dev);
-	wcd9xxx->dev_up = false;
 	mutex_unlock(&wcd9xxx->reset_lock);
 
 	return 0;