[PATCH v2 1/2] mmc: atmel-mci: Switch to using managed resource in probe

[Pramod Gurav]

This change uses managed resource APIs to allocate resources such as,
clk, gpio, io in order to simplify the driver unload or failure cases.
Hence does away with release statements of the same resources in error
labels and remove function.

Acked-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
Cc: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
Cc: Chris Ball <chris@xxxxxxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Cc: linux-mmc@xxxxxxxxxxxxxxx
Signed-off-by: Pramod Gurav <pramod.gurav@xxxxxxxxxxxxxxx>

---
Changes since v1:
- Dropped using devm_request_irq as suggested by Ludovic Desroches
  as it seems there are race conditions seen with them.
- Added another patch to fix failure path in probe to call atmci_cleanup_slot
  after dma_alloc_coherent() fails to release mmc_host resources.
- Fixed typos in commit message
---
 drivers/mmc/host/atmel-mci.c |   41 ++++++++++++++---------------------------
 1 file changed, 14 insertions(+), 27 deletions(-)

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index bb585d9..36212fb 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -17,6 +17,7 @@
 #include <linux/gpio.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
 #include <linux/of.h>
@@ -2195,7 +2196,8 @@ static int __init atmci_init_slot(struct atmel_mci *host,
 	/* Assume card is present initially */
 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
 	if (gpio_is_valid(slot->detect_pin)) {
-		if (gpio_request(slot->detect_pin, "mmc_detect")) {
+		if (devm_gpio_request(&host->pdev->dev, slot->detect_pin,
+				      "mmc_detect")) {
 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
 			slot->detect_pin = -EBUSY;
 		} else if (gpio_get_value(slot->detect_pin) ^
@@ -2208,7 +2210,8 @@ static int __init atmci_init_slot(struct atmel_mci *host,
 		mmc->caps |= MMC_CAP_NEEDS_POLL;
 
 	if (gpio_is_valid(slot->wp_pin)) {
-		if (gpio_request(slot->wp_pin, "mmc_wp")) {
+		if (devm_gpio_request(&host->pdev->dev, slot->wp_pin,
+				      "mmc_wp")) {
 			dev_dbg(&mmc->class_dev, "no WP pin available\n");
 			slot->wp_pin = -EBUSY;
 		}
@@ -2232,7 +2235,6 @@ static int __init atmci_init_slot(struct atmel_mci *host,
 			dev_dbg(&mmc->class_dev,
 				"could not request IRQ %d for detect pin\n",
 				gpio_to_irq(slot->detect_pin));
-			gpio_free(slot->detect_pin);
 			slot->detect_pin = -EBUSY;
 		}
 	}
@@ -2257,10 +2259,7 @@ static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
 
 		free_irq(gpio_to_irq(pin), slot);
 		del_timer_sync(&slot->detect_timer);
-		gpio_free(pin);
 	}
-	if (gpio_is_valid(slot->wp_pin))
-		gpio_free(slot->wp_pin);
 
 	slot->host->slot[id] = NULL;
 	mmc_free_host(slot->mmc);
@@ -2395,7 +2394,7 @@ static int __init atmci_probe(struct platform_device *pdev)
 	if (irq < 0)
 		return irq;
 
-	host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL);
+	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
 	if (!host)
 		return -ENOMEM;
 
@@ -2403,20 +2402,18 @@ static int __init atmci_probe(struct platform_device *pdev)
 	spin_lock_init(&host->lock);
 	INIT_LIST_HEAD(&host->queue);
 
-	host->mck = clk_get(&pdev->dev, "mci_clk");
-	if (IS_ERR(host->mck)) {
-		ret = PTR_ERR(host->mck);
-		goto err_clk_get;
-	}
+	host->mck = devm_clk_get(&pdev->dev, "mci_clk");
+	if (IS_ERR(host->mck))
+		return PTR_ERR(host->mck);
 
-	ret = -ENOMEM;
-	host->regs = ioremap(regs->start, resource_size(regs));
+	host->regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
 	if (!host->regs)
-		goto err_ioremap;
+		return -ENOMEM;
 
 	ret = clk_prepare_enable(host->mck);
 	if (ret)
-		goto err_request_irq;
+		return ret;
+
 	atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
 	host->bus_hz = clk_get_rate(host->mck);
 	clk_disable_unprepare(host->mck);
@@ -2427,7 +2424,7 @@ static int __init atmci_probe(struct platform_device *pdev)
 
 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
 	if (ret)
-		goto err_request_irq;
+		return ret;
 
 	/* Get MCI capabilities and set operations according to it */
 	atmci_get_cap(host);
@@ -2499,12 +2496,6 @@ err_init_slot:
 	if (host->dma.chan)
 		dma_release_channel(host->dma.chan);
 	free_irq(irq, host);
-err_request_irq:
-	iounmap(host->regs);
-err_ioremap:
-	clk_put(host->mck);
-err_clk_get:
-	kfree(host);
 	return ret;
 }
 
@@ -2532,10 +2523,6 @@ static int __exit atmci_remove(struct platform_device *pdev)
 		dma_release_channel(host->dma.chan);
 
 	free_irq(platform_get_irq(pdev, 0), host);
-	iounmap(host->regs);
-
-	clk_put(host->mck);
-	kfree(host);
 
 	return 0;
 }
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/