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regulator: max8997: Properly handle gpio_request failure

PATCH Applied Axel Lin 2 participants 3 messages Jul 5, 2012 – Jul 15, 2012

Subsystems (2)
Voltage and current regulator framework Samsung multifunction PMIC device drivers
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Axel Lin

author
#0 lore raw

PATCH 1/2 regulator: max8997: Properly handle gpio_request failure

Convert to devm_gpio_request to save a few error handling code.

This patch properly handle the gpio_request failure with -EBUSY, we should return error rather than ommit the gpio_request failure with -EBUSY.

I think one of the reason we got -EBUSY is because current code does not free gpios in max8997_pmic_remove(). So it got -EBUSY when reload the module.

Yest another reason is in current code if gpio_request() returns -EBUSY, the rest of the code still calls gpio_direction_output to config buck125_gpios and set gpio value in max8997_set_gpio(). This looks wrong to me.

Signed-off-by Axel Lin <[email protected]>
---
 drivers/regulator/max8997.c |   40 +++++++++-------------------------------
 1 file changed, 9 insertions(+), 31 deletions(-)
drivers/regulator/max8997.c +9 -31
index 704cd49..e39a0c7 100644
@@ -1025,7 +1025,6 @@ static __devinit int max8997_pmic_probe(struct platform_device *pdev)
 	 */
 	if (pdata->buck1_gpiodvs || pdata->buck2_gpiodvs ||
 			pdata->buck5_gpiodvs) {
-		bool gpio1set = false, gpio2set = false;
 
 		if (!gpio_is_valid(pdata->buck125_gpios[0]) ||
 				!gpio_is_valid(pdata->buck125_gpios[1]) ||

@@ -1035,40 +1034,20 @@ static __devinit int max8997_pmic_probe(struct platform_device *pdev)
 			goto err_out;
 		}
 
-		ret = gpio_request(pdata->buck125_gpios[0],
-				"MAX8997 SET1");
-		if (ret == -EBUSY)
-			dev_warn(&pdev->dev, "Duplicated gpio request"
-					" on SET1\n");
-		else if (ret)
+		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[0],
+					"MAX8997 SET1");
+		if (ret)
 			goto err_out;
-		else
-			gpio1set = true;
-
-		ret = gpio_request(pdata->buck125_gpios[1],
-				"MAX8997 SET2");
-		if (ret == -EBUSY)
-			dev_warn(&pdev->dev, "Duplicated gpio request"
-					" on SET2\n");
-		else if (ret) {
-			if (gpio1set)
-				gpio_free(pdata->buck125_gpios[0]);
+
+		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[1],
+					"MAX8997 SET2");
+		if (ret)
 			goto err_out;
-		} else
-			gpio2set = true;
 
-		ret = gpio_request(pdata->buck125_gpios[2],
+		ret = devm_gpio_request(&pdev->dev, pdata->buck125_gpios[2],
 				"MAX8997 SET3");
-		if (ret == -EBUSY)
-			dev_warn(&pdev->dev, "Duplicated gpio request"
-					" on SET3\n");
-		else if (ret) {
-			if (gpio1set)
-				gpio_free(pdata->buck125_gpios[0]);
-			if (gpio2set)
-				gpio_free(pdata->buck125_gpios[1]);
+		if (ret)
 			goto err_out;
-		}
 
 		gpio_direction_output(pdata->buck125_gpios[0],
 				(max8997->buck125_gpioindex >> 2)

@@ -1079,7 +1058,6 @@ static __devinit int max8997_pmic_probe(struct platform_device *pdev)
 		gpio_direction_output(pdata->buck125_gpios[2],
 				(max8997->buck125_gpioindex >> 0)
 				& 0x1); /* SET3 */
-		ret = 0;
 	}
 
 	/* DVS-GPIO disabled */
Signature · 1 line
1.7.9.5
author
#1 lore raw

PATCH 2/2 regulator: s5m8767: Properly handle gpio_request failure

Convert to devm_gpio_request to save a few error handling code.

This patch properly handle the gpio_request failure, we should return error when gpio_request fails rather than just show warning.

I think one of the reason we got -EBUSY is because current code does not free gpios in s5m8767_pmic_remove(). So it got -EBUSY when reload the module.

Yest another reason is in current code if gpio_request() returns error, the rest of the code still calls gpio_direction_output to config buck_gpios and buck_ds gpios. This looks wrong to me.

Signed-off-by Axel Lin <[email protected]>
---
 drivers/regulator/s5m8767.c |   49 +++++++++++++++++++++----------------------
 1 file changed, 24 insertions(+), 25 deletions(-)
drivers/regulator/s5m8767.c +24 -25
index 5df3358..297f696 100644
@@ -559,20 +559,21 @@ static __devinit int s5m8767_pmic_probe(struct platform_device *pdev)
 	if (gpio_is_valid(pdata->buck_gpios[0]) &&
 		gpio_is_valid(pdata->buck_gpios[1]) &&
 		gpio_is_valid(pdata->buck_gpios[2])) {
-		ret = gpio_request(pdata->buck_gpios[0], "S5M8767 SET1");
-		if (ret == -EBUSY)
-			dev_warn(&pdev->dev, "Duplicated gpio request"
-				" for SET1\n");
-
-		ret = gpio_request(pdata->buck_gpios[1], "S5M8767 SET2");
-		if (ret == -EBUSY)
-			dev_warn(&pdev->dev, "Duplicated gpio request"
-				" for SET2\n");
-
-		ret = gpio_request(pdata->buck_gpios[2], "S5M8767 SET3");
-		if (ret == -EBUSY)
-			dev_warn(&pdev->dev, "Duplicated gpio request"
-					" for SET3\n");
+		ret = devm_gpio_request(&pdev->dev, pdata->buck_gpios[0],
+					"S5M8767 SET1");
+		if (ret)
+			return ret;
+
+		ret = devm_gpio_request(&pdev->dev, pdata->buck_gpios[1],
+					"S5M8767 SET2");
+		if (ret)
+			return ret;
+
+		ret = devm_gpio_request(&pdev->dev, pdata->buck_gpios[2],
+					"S5M8767 SET3");
+		if (ret)
+			return ret;
+
 		/* SET1 GPIO */
 		gpio_direction_output(pdata->buck_gpios[0],
 				(s5m8767->buck_gpioindex >> 2) & 0x1);

@@ -582,25 +583,23 @@ static __devinit int s5m8767_pmic_probe(struct platform_device *pdev)
 		/* SET3 GPIO */
 		gpio_direction_output(pdata->buck_gpios[2],
 				(s5m8767->buck_gpioindex >> 0) & 0x1);
-		ret = 0;
-
 	} else {
 		dev_err(&pdev->dev, "GPIO NOT VALID\n");
 		ret = -EINVAL;
 		return ret;
 	}
 
-	ret = gpio_request(pdata->buck_ds[0], "S5M8767 DS2");
-	if (ret == -EBUSY)
-		dev_warn(&pdev->dev, "Duplicated gpio request for DS2\n");
+	ret = devm_gpio_request(&pdev->dev, pdata->buck_ds[0], "S5M8767 DS2");
+	if (ret)
+		return ret;
 
-	ret = gpio_request(pdata->buck_ds[1], "S5M8767 DS3");
-	if (ret == -EBUSY)
-		dev_warn(&pdev->dev, "Duplicated gpio request for DS3\n");
+	ret = devm_gpio_request(&pdev->dev, pdata->buck_ds[1], "S5M8767 DS3");
+	if (ret)
+		return ret;
 
-	ret = gpio_request(pdata->buck_ds[2], "S5M8767 DS4");
-	if (ret == -EBUSY)
-		dev_warn(&pdev->dev, "Duplicated gpio request for DS4\n");
+	ret = devm_gpio_request(&pdev->dev, pdata->buck_ds[2], "S5M8767 DS4");
+	if (ret)
+		return ret;
 
 	/* DS2 GPIO */
 	gpio_direction_output(pdata->buck_ds[0], 0x0);
Signature · 1 line
1.7.9.5