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

[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 resorces in error
lables and remove function.

Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Chris Ball <chris@printf.net>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-mmc@vger.kernel.org
Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>

---
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.
---
 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

[PATCH v2 2/2] mmc: atmel-mci: Release mmc resources on failure in probe

[Pramod Gurav]

This change takes care of releasing mmc resources on error cases in
probe function which was missing. Also release timer in remove function.

Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Chris Ball <chris@printf.net>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-mmc@vger.kernel.org
Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
---
Changes since v1: None

 drivers/mmc/host/atmel-mci.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 36212fb..288bcc1 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -2376,7 +2376,7 @@ static int __init atmci_probe(struct platform_device *pdev)
 	struct resource			*regs;
 	unsigned int			nr_slots;
 	int				irq;
-	int				ret;
+	int				ret, i;
 
 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!regs)
@@ -2482,7 +2482,7 @@ static int __init atmci_probe(struct platform_device *pdev)
 		if (!host->buffer) {
 			ret = -ENOMEM;
 			dev_err(&pdev->dev, "buffer allocation failed\n");
-			goto err_init_slot;
+			goto err_dma_alloc;
 		}
 	}
 
@@ -2492,7 +2492,13 @@ static int __init atmci_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_dma_alloc:
+	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
+		if (host->slot[i])
+			atmci_cleanup_slot(host->slot[i], i);
+	}
 err_init_slot:
+	del_timer_sync(&host->timer);
 	if (host->dma.chan)
 		dma_release_channel(host->dma.chan);
 	free_irq(irq, host);
@@ -2519,6 +2525,7 @@ static int __exit atmci_remove(struct platform_device *pdev)
 	atmci_readl(host, ATMCI_SR);
 	clk_disable_unprepare(host->mck);
 
+	del_timer_sync(&host->timer);
 	if (host->dma.chan)
 		dma_release_channel(host->dma.chan);
 
-- 
1.7.9.5

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

[Ludovic Desroches]

On Tue, Sep 23, 2014 at 03:50:05PM +0530, Pramod Gurav wrote:
> 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 resorces in error
/s/resorces/resources
> lables and remove function.
/s/lables/labels

Otherwise

Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>

Thanks

> 
> Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
> Cc: Chris Ball <chris@printf.net>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: linux-mmc@vger.kernel.org
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
> 
> ---
> 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.
> ---
>  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
> 

Re: [PATCH v2 2/2] mmc: atmel-mci: Release mmc resources on failure in probe

[Ludovic Desroches]

On Tue, Sep 23, 2014 at 03:50:06PM +0530, Pramod Gurav wrote:
> This change takes care of releasing mmc resources on error cases in
> probe function which was missing. Also release timer in remove function.
> 

Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>

> Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
> Cc: Chris Ball <chris@printf.net>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: linux-mmc@vger.kernel.org
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
> ---
> Changes since v1: None
> 
>  drivers/mmc/host/atmel-mci.c |   11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 36212fb..288bcc1 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -2376,7 +2376,7 @@ static int __init atmci_probe(struct platform_device *pdev)
>  	struct resource			*regs;
>  	unsigned int			nr_slots;
>  	int				irq;
> -	int				ret;
> +	int				ret, i;
>  
>  	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	if (!regs)
> @@ -2482,7 +2482,7 @@ static int __init atmci_probe(struct platform_device *pdev)
>  		if (!host->buffer) {
>  			ret = -ENOMEM;
>  			dev_err(&pdev->dev, "buffer allocation failed\n");
> -			goto err_init_slot;
> +			goto err_dma_alloc;
>  		}
>  	}
>  
> @@ -2492,7 +2492,13 @@ static int __init atmci_probe(struct platform_device *pdev)
>  
>  	return 0;
>  
> +err_dma_alloc:
> +	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
> +		if (host->slot[i])
> +			atmci_cleanup_slot(host->slot[i], i);
> +	}
>  err_init_slot:
> +	del_timer_sync(&host->timer);
>  	if (host->dma.chan)
>  		dma_release_channel(host->dma.chan);
>  	free_irq(irq, host);
> @@ -2519,6 +2525,7 @@ static int __exit atmci_remove(struct platform_device *pdev)
>  	atmci_readl(host, ATMCI_SR);
>  	clk_disable_unprepare(host->mck);
>  
> +	del_timer_sync(&host->timer);
>  	if (host->dma.chan)
>  		dma_release_channel(host->dma.chan);
>  
> -- 
> 1.7.9.5
> 

Re: [PATCH v2 2/2] mmc: atmel-mci: Release mmc resources on failure in probe

[Ulf Hansson]

On 23 September 2014 12:20, Pramod Gurav <pramod.gurav@smartplayin.com> wrote:
> This change takes care of releasing mmc resources on error cases in
> probe function which was missing. Also release timer in remove function.
>
> Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
> Cc: Chris Ball <chris@printf.net>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: linux-mmc@vger.kernel.org
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>

Thanks! Applied for next.

Kind regards
Uffe

> ---
> Changes since v1: None
>
>  drivers/mmc/host/atmel-mci.c |   11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 36212fb..288bcc1 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -2376,7 +2376,7 @@ static int __init atmci_probe(struct platform_device *pdev)
>         struct resource                 *regs;
>         unsigned int                    nr_slots;
>         int                             irq;
> -       int                             ret;
> +       int                             ret, i;
>
>         regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>         if (!regs)
> @@ -2482,7 +2482,7 @@ static int __init atmci_probe(struct platform_device *pdev)
>                 if (!host->buffer) {
>                         ret = -ENOMEM;
>                         dev_err(&pdev->dev, "buffer allocation failed\n");
> -                       goto err_init_slot;
> +                       goto err_dma_alloc;
>                 }
>         }
>
> @@ -2492,7 +2492,13 @@ static int __init atmci_probe(struct platform_device *pdev)
>
>         return 0;
>
> +err_dma_alloc:
> +       for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
> +               if (host->slot[i])
> +                       atmci_cleanup_slot(host->slot[i], i);
> +       }
>  err_init_slot:
> +       del_timer_sync(&host->timer);
>         if (host->dma.chan)
>                 dma_release_channel(host->dma.chan);
>         free_irq(irq, host);
> @@ -2519,6 +2525,7 @@ static int __exit atmci_remove(struct platform_device *pdev)
>         atmci_readl(host, ATMCI_SR);
>         clk_disable_unprepare(host->mck);
>
> +       del_timer_sync(&host->timer);
>         if (host->dma.chan)
>                 dma_release_channel(host->dma.chan);
>
> --
> 1.7.9.5
>

[PATCH] mmc: atmel-mci: fix mismatched section on atmci_cleanup_slot

[Arnd Bergmann]

As of 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe"),
the atmci_probe() function calls atmci_cleanup_slot in the failure path.

This causes a new warning whenever the driver is built:

WARNING: drivers/mmc/host/built-in.o(.init.text+0xa04): Section mismatch in reference from the function atmci_probe() to the function .exit.text:atmci_cleanup_slot()
The function __init atmci_probe() references
a function __exit atmci_cleanup_slot().

Gcc correctly warns about this function getting dropped in the link stage
for the built-in case, which would cause undefined behavior when this error
path is hit. The solution is to simply drop the __exit annotation.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe")

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 772ef5b0e4d5..974626087732 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -2244,7 +2244,7 @@ static int __init atmci_init_slot(struct atmel_mci *host,
 	return 0;
 }
 
-static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
+static void atmci_cleanup_slot(struct atmel_mci_slot *slot,
 		unsigned int id)
 {
 	/* Debugfs stuff is cleaned up by mmc core */

Re: [PATCH] mmc: atmel-mci: fix mismatched section on atmci_cleanup_slot

[Pramod Gurav]

Hi Arnd,

On Sat, Sep 27, 2014 at 1:04 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> As of 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe"),
> the atmci_probe() function calls atmci_cleanup_slot in the failure path.
>
> This causes a new warning whenever the driver is built:
>
> WARNING: drivers/mmc/host/built-in.o(.init.text+0xa04): Section mismatch in reference from the function atmci_probe() to the function .exit.text:atmci_cleanup_slot()
> The function __init atmci_probe() references
> a function __exit atmci_cleanup_slot().
Thanks for this though I am not owner of the driver but the last
commit was mine.
but how come I did not see this warning? Any flag with compiler that
warned about this?
>
> Gcc correctly warns about this function getting dropped in the link stage
> for the built-in case, which would cause undefined behavior when this error
> path is hit. The solution is to simply drop the __exit annotation.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Fixes: 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe")
>
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 772ef5b0e4d5..974626087732 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -2244,7 +2244,7 @@ static int __init atmci_init_slot(struct atmel_mci *host,
>         return 0;
>  }
>
> -static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
> +static void atmci_cleanup_slot(struct atmel_mci_slot *slot,
>                 unsigned int id)
>  {
>         /* Debugfs stuff is cleaned up by mmc core */
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/



-- 
Thanks and Regards
Pramod

Re: [PATCH] mmc: atmel-mci: fix mismatched section on atmci_cleanup_slot

[Arnd Bergmann]

On Saturday 27 September 2014 08:45:33 Pramod Gurav wrote:
> Hi Arnd,
> 
> On Sat, Sep 27, 2014 at 1:04 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> > As of 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe"),
> > the atmci_probe() function calls atmci_cleanup_slot in the failure path.
> >
> > This causes a new warning whenever the driver is built:
> >
> > WARNING: drivers/mmc/host/built-in.o(.init.text+0xa04): Section mismatch in reference from the function atmci_probe() to the function .exit.text:atmci_cleanup_slot()
> > The function __init atmci_probe() references
> > a function __exit atmci_cleanup_slot().
> Thanks for this though I am not owner of the driver but the last
> commit was mine.
> but how come I did not see this warning? Any flag with compiler that
> warned about this?

The warning above is only enabled if CONFIG_DEBUG_SECTION_MISMATCH is set, otherwise
you get this one:

WARNING: modpost: Found 1 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'

	Arnd

Re: [PATCH] mmc: atmel-mci: fix mismatched section on atmci_cleanup_slot

[Ludovic Desroches]

On Fri, Sep 26, 2014 at 09:34:58PM +0200, Arnd Bergmann wrote:
> As of 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe"),
> the atmci_probe() function calls atmci_cleanup_slot in the failure path.
> 
> This causes a new warning whenever the driver is built:
> 
> WARNING: drivers/mmc/host/built-in.o(.init.text+0xa04): Section mismatch in reference from the function atmci_probe() to the function .exit.text:atmci_cleanup_slot()
> The function __init atmci_probe() references
> a function __exit atmci_cleanup_slot().
> 
> Gcc correctly warns about this function getting dropped in the link stage
> for the built-in case, which would cause undefined behavior when this error
> path is hit. The solution is to simply drop the __exit annotation.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>

Thanks, I also missed this warning when compiling.

> Fixes: 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe")
> 
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 772ef5b0e4d5..974626087732 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -2244,7 +2244,7 @@ static int __init atmci_init_slot(struct atmel_mci *host,
>  	return 0;
>  }
>  
> -static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
> +static void atmci_cleanup_slot(struct atmel_mci_slot *slot,
>  		unsigned int id)
>  {
>  	/* Debugfs stuff is cleaned up by mmc core */

Re: [PATCH] mmc: atmel-mci: fix mismatched section on atmci_cleanup_slot

[Ulf Hansson]

On 26 September 2014 21:34, Arnd Bergmann <arnd@arndb.de> wrote:
> As of 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe"),
> the atmci_probe() function calls atmci_cleanup_slot in the failure path.
>
> This causes a new warning whenever the driver is built:
>
> WARNING: drivers/mmc/host/built-in.o(.init.text+0xa04): Section mismatch in reference from the function atmci_probe() to the function .exit.text:atmci_cleanup_slot()
> The function __init atmci_probe() references
> a function __exit atmci_cleanup_slot().
>
> Gcc correctly warns about this function getting dropped in the link stage
> for the built-in case, which would cause undefined behavior when this error
> path is hit. The solution is to simply drop the __exit annotation.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Fixes: 528bc7808f4e ("mmc: atmel-mci: Release mmc resources on failure in probe")

Thanks! Applied for next!

Kind regards
Uffe

>
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 772ef5b0e4d5..974626087732 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -2244,7 +2244,7 @@ static int __init atmci_init_slot(struct atmel_mci *host,
>         return 0;
>  }
>
> -static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
> +static void atmci_cleanup_slot(struct atmel_mci_slot *slot,
>                 unsigned int id)
>  {
>         /* Debugfs stuff is cleaned up by mmc core */

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

[Ulf Hansson]

On 23 September 2014 14:51, Pramod Gurav <pramod.gurav@smartplayin.com> wrote:
> 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@atmel.com>
> Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
> Cc: Chris Ball <chris@printf.net>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: linux-mmc@vger.kernel.org
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>

Thanks! Applied for next.

You don't need this extensive list of "Cc" in the commit message for
future patches. It's also recommended to add acks etc in chronological
order, thus Ludovic's ack should have been put below your sob.

Kind regards
Uffe

>
> ---
> 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
>

[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@atmel.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Chris Ball <chris@printf.net>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-mmc@vger.kernel.org
Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>

---
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