linux-kernel - [PATCH v3] mfd: wm831x: Remove redundant forever while loop

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Message-ID: <20231129132816.15620-1-mstrozek@opensource.cirrus.com>
Date:   Wed, 29 Nov 2023 13:28:16 +0000
From:   Maciej Strozek <mstrozek@...nsource.cirrus.com>
To:     Lee Jones <lee@...nel.org>
CC:     <patches@...nsource.cirrus.com>, <linux-kernel@...r.kernel.org>,
        "Maciej Strozek" <mstrozek@...nsource.cirrus.com>
Subject: [PATCH v3] mfd: wm831x: Remove redundant forever while loop

Current code excutes only once despite the while loop, so remove the
loop. Also msleep(1) will likely result in a larger sleep, so increase
its value for clarity while keeping the same behaviour.

Signed-off-by: Maciej Strozek <mstrozek@...nsource.cirrus.com>
---
V2 -> V3: formatting changes: fixed a comment and 2 line-ups, added a new line
V1 -> V2: removed unused variable 'timeout'

 drivers/mfd/wm831x-auxadc.c | 43 ++++++++++++++++---------------------
 1 file changed, 18 insertions(+), 25 deletions(-)

diff --git a/drivers/mfd/wm831x-auxadc.c b/drivers/mfd/wm831x-auxadc.c
index 65b98f3fbd92..18618a8f9206 100644
--- a/drivers/mfd/wm831x-auxadc.c
+++ b/drivers/mfd/wm831x-auxadc.c
@@ -152,7 +152,7 @@ static irqreturn_t wm831x_auxadc_irq(int irq, void *irq_data)
 static int wm831x_auxadc_read_polled(struct wm831x *wm831x,
 				     enum wm831x_auxadc input)
 {
-	int ret, src, timeout;
+	int ret, src;

 	mutex_lock(&wm831x->auxadc_lock);

@@ -179,32 +179,25 @@ static int wm831x_auxadc_read_polled(struct wm831x *wm831x,
 		goto disable;
 	}

-	/* If we're not using interrupts then poll the
-	 * interrupt status register */
-	timeout = 5;
-	while (timeout) {
-		msleep(1);
+	/* If we're not using interrupts then read the interrupt status register */
+	msleep(20);

-		ret = wm831x_reg_read(wm831x,
-				      WM831X_INTERRUPT_STATUS_1);
-		if (ret < 0) {
-			dev_err(wm831x->dev,
-				"ISR 1 read failed: %d\n", ret);
-			goto disable;
-		}
+	ret = wm831x_reg_read(wm831x, WM831X_INTERRUPT_STATUS_1);
+	if (ret < 0) {
+		dev_err(wm831x->dev,
+			"ISR 1 read failed: %d\n", ret);
+		goto disable;
+	}

-		/* Did it complete? */
-		if (ret & WM831X_AUXADC_DATA_EINT) {
-			wm831x_reg_write(wm831x,
-					 WM831X_INTERRUPT_STATUS_1,
-					 WM831X_AUXADC_DATA_EINT);
-			break;
-		} else {
-			dev_err(wm831x->dev,
-				"AUXADC conversion timeout\n");
-			ret = -EBUSY;
-			goto disable;
-		}
+	/* Did it complete? */
+	if (ret & WM831X_AUXADC_DATA_EINT) {
+		wm831x_reg_write(wm831x, WM831X_INTERRUPT_STATUS_1,
+				WM831X_AUXADC_DATA_EINT);
+	} else {
+		dev_err(wm831x->dev,
+			"AUXADC conversion timeout\n");
+		ret = -EBUSY;
+		goto disable;
 	}

 	ret = wm831x_reg_read(wm831x, WM831X_AUXADC_DATA);
--
2.34.1