[PATCH v2 1/2] hw_random: mxc-rnga: Adapt clocks to new i.mx clock framework

[PATCH v2 1/2] hw_random: mxc-rnga: Adapt clocks to new i.mx clock framework

[Fabio Estevam]

Adapt clocks to the new i.mx clock framework and fix the following warning:
                             
------------[ cut here ]------------                                            
WARNING: at drivers/clk/clk.c:511 __clk_enable+0x9c/0xac()                      
Modules linked in:                                                              
Backtrace:                                                                      
[<800124c8>] (dump_backtrace+0x0/0x10c) from [<804172dc>] (dump_stack+0x18/0x1c)
 r7:00000009 r6:000001ff r5:8032cb50 r4:00000000                                
[<804172c4>] (dump_stack+0x0/0x1c) from [<80021834>] (warn_slowpath_common+0x54)
[<800217e0>] (warn_slowpath_common+0x0/0x6c) from [<80021870>] (warn_slowpath_n)
 r9:80581cac r8:8700a9c0 r7:805ab070 r6:80000013 r5:806133d4                    
r4:8700a9c0                                                                     
[<8002184c>] (warn_slowpath_null+0x0/0x2c) from [<8032cb50>] (__clk_enable+0x9c)
[<8032cab4>] (__clk_enable+0x0/0xac) from [<8032cb88>] (clk_enable+0x28/0x44)   
 r5:806133d4 r4:8700a9c0                                                        
[<8032cb60>] (clk_enable+0x0/0x44) from [<80560f14>] (mxc_rnga_probe+0x68/0x164)
 r7:805ab070 r6:8706ec00 r5:80611314 r4:00000000                                
[<80560eac>] (mxc_rnga_probe+0x0/0x164) from [<8025914c>] (platform_drv_probe+0)
[<8025912c>] (platform_drv_probe+0x0/0x24) from [<80257c7c>] (driver_probe_devi)
[<80257bfc>] (driver_probe_device+0x0/0x204) from [<80257e94>] (__driver_attach)
 r9:80581cac r8:0000008e r7:00000000 r6:8706ec3c r5:805ab070                    
r4:8706ec08                                                                     
[<80257e00>] (__driver_attach+0x0/0x98) from [<8025642c>] (bus_for_each_dev+0x6)
 r7:00000000 r6:80257e00 r5:87035e98 r4:805ab070                                
[<802563c4>] (bus_for_each_dev+0x0/0x94) from [<80257adc>] (driver_attach+0x20/)
 r7:00000000 r6:873f2380 r5:805ab338 r4:805ab070                                
[<80257abc>] (driver_attach+0x0/0x28) from [<80256d50>] (bus_add_driver+0x18c/0)
[<80256bc4>] (bus_add_driver+0x0/0x268) from [<802584c4>] (driver_register+0x80)
[<80258444>] (driver_register+0x0/0x134) from [<802594f4>] (platform_driver_reg)
 r7:00000000 r6:805c2e00 r5:00000007 r4:805ab05c                                
[<802594a8>] (platform_driver_register+0x0/0x60) from [<80259528>] (platform_dr)
[<80259508>] (platform_driver_probe+0x0/0xa4) from [<80560ea0>] (mod_init+0x18/)
 r7:00000000 r6:805c2e00 r5:00000007 r4:87034000                                
[<80560e88>] (mod_init+0x0/0x24) from [<800086b4>] (do_one_initcall+0x40/0x194) 
[<80008674>] (do_one_initcall+0x0/0x194) from [<8053d3f4>] (kernel_init+0xfc/0x)
[<8053d2f8>] (kernel_init+0x0/0x1cc) from [<80027190>] (do_exit+0x0/0x7ec)      
---[ end trace 4198eed02050f461 ]---                                            
mxc_rnga mxc_rnga: MXC RNGA Registered

Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Herbert Xu <herbert@gondor.apana.org.au> 
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
Changes since v1:
- Converted a missing 'clk_disable' to 'clk_disable_unprepare'

 drivers/char/hw_random/mxc-rnga.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c
index 85074de..62c7efe 100644
--- a/drivers/char/hw_random/mxc-rnga.c
+++ b/drivers/char/hw_random/mxc-rnga.c
@@ -152,14 +152,14 @@ static int __init mxc_rnga_probe(struct platform_device *pdev)
 	if (rng_dev)
 		return -EBUSY;
 
-	clk = clk_get(&pdev->dev, "rng");
+	clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "Could not get rng_clk!\n");
 		err = PTR_ERR(clk);
 		goto out;
 	}
 
-	clk_enable(clk);
+	clk_prepare_enable(clk);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
@@ -201,7 +201,7 @@ err_ioremap:
 	release_mem_region(res->start, resource_size(res));
 
 err_region:
-	clk_disable(clk);
+	clk_disable_unprepare(clk);
 	clk_put(clk);
 
 out:
@@ -212,7 +212,7 @@ static int __exit mxc_rnga_remove(struct platform_device *pdev)
 {
 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	void __iomem *rng_base = (void __iomem *)mxc_rnga.priv;
-	struct clk *clk = clk_get(&pdev->dev, "rng");
+	struct clk *clk = clk_get(&pdev->dev, NULL);
 
 	hwrng_unregister(&mxc_rnga);
 
@@ -220,7 +220,7 @@ static int __exit mxc_rnga_remove(struct platform_device *pdev)
 
 	release_mem_region(res->start, resource_size(res));
 
-	clk_disable(clk);
+	clk_disable_unprepare(clk);
 	clk_put(clk);
 
 	return 0;
-- 
1.7.1

[PATCH v2 2/2] hw_random: mxc-rnga: Access data via structure

[Fabio Estevam]

In current driver, everytime we need to access the rng clock (,ie to enable or disable it) a call to clk_get is done.

This is not correct and the preferred way is to provide a rng data structure that could be used for accessing rng resources. 

Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Herbert Xu <herbert@gondor.apana.org.au> 
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
Changes since v1:
- No changes. Newly introduced in this version
 drivers/char/hw_random/mxc-rnga.c |  108 +++++++++++++++++-------------------
 1 files changed, 51 insertions(+), 57 deletions(-)

diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c
index 62c7efe..f05d857 100644
--- a/drivers/char/hw_random/mxc-rnga.c
+++ b/drivers/char/hw_random/mxc-rnga.c
@@ -59,16 +59,21 @@
 #define RNGA_STATUS_LAST_READ_STATUS	0x00000002
 #define RNGA_STATUS_SECURITY_VIOLATION	0x00000001
 
-static struct platform_device *rng_dev;
+struct mxc_rng {
+	struct device *dev;
+	struct hwrng rng;
+	void __iomem *mem;
+	struct clk *clk;
+};
 
 static int mxc_rnga_data_present(struct hwrng *rng, int wait)
 {
-	void __iomem *rng_base = (void __iomem *)rng->priv;
 	int i;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
 
 	for (i = 0; i < 20; i++) {
 		/* how many random numbers are in FIFO? [0-16] */
-		int level = (__raw_readl(rng_base + RNGA_STATUS) &
+		int level = (__raw_readl(mxc_rng->mem + RNGA_STATUS) &
 				RNGA_STATUS_LEVEL_MASK) >> 8;
 		if (level || !wait)
 			return !!level;
@@ -81,20 +86,20 @@ static int mxc_rnga_data_read(struct hwrng *rng, u32 * data)
 {
 	int err;
 	u32 ctrl;
-	void __iomem *rng_base = (void __iomem *)rng->priv;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
 
 	/* retrieve a random number from FIFO */
-	*data = __raw_readl(rng_base + RNGA_OUTPUT_FIFO);
+	*data = __raw_readl(mxc_rng->mem + RNGA_OUTPUT_FIFO);
 
 	/* some error while reading this random number? */
-	err = __raw_readl(rng_base + RNGA_STATUS) & RNGA_STATUS_ERROR_INT;
+	err = __raw_readl(mxc_rng->mem + RNGA_STATUS) & RNGA_STATUS_ERROR_INT;
 
 	/* if error: clear error interrupt, but doesn't return random number */
 	if (err) {
-		dev_dbg(&rng_dev->dev, "Error while reading random number!\n");
-		ctrl = __raw_readl(rng_base + RNGA_CONTROL);
+		dev_dbg(mxc_rng->dev, "Error while reading random number!\n");
+		ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
 		__raw_writel(ctrl | RNGA_CONTROL_CLEAR_INT,
-					rng_base + RNGA_CONTROL);
+					mxc_rng->mem + RNGA_CONTROL);
 		return 0;
 	} else
 		return 4;
@@ -103,22 +108,22 @@ static int mxc_rnga_data_read(struct hwrng *rng, u32 * data)
 static int mxc_rnga_init(struct hwrng *rng)
 {
 	u32 ctrl, osc;
-	void __iomem *rng_base = (void __iomem *)rng->priv;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
 
 	/* wake up */
-	ctrl = __raw_readl(rng_base + RNGA_CONTROL);
-	__raw_writel(ctrl & ~RNGA_CONTROL_SLEEP, rng_base + RNGA_CONTROL);
+	ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
+	__raw_writel(ctrl & ~RNGA_CONTROL_SLEEP, mxc_rng->mem + RNGA_CONTROL);
 
 	/* verify if oscillator is working */
-	osc = __raw_readl(rng_base + RNGA_STATUS);
+	osc = __raw_readl(mxc_rng->mem + RNGA_STATUS);
 	if (osc & RNGA_STATUS_OSC_DEAD) {
-		dev_err(&rng_dev->dev, "RNGA Oscillator is dead!\n");
+		dev_err(mxc_rng->dev, "RNGA Oscillator is dead!\n");
 		return -ENODEV;
 	}
 
 	/* go running */
-	ctrl = __raw_readl(rng_base + RNGA_CONTROL);
-	__raw_writel(ctrl | RNGA_CONTROL_GO, rng_base + RNGA_CONTROL);
+	ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
+	__raw_writel(ctrl | RNGA_CONTROL_GO, mxc_rng->mem + RNGA_CONTROL);
 
 	return 0;
 }
@@ -126,40 +131,40 @@ static int mxc_rnga_init(struct hwrng *rng)
 static void mxc_rnga_cleanup(struct hwrng *rng)
 {
 	u32 ctrl;
-	void __iomem *rng_base = (void __iomem *)rng->priv;
+	struct mxc_rng *mxc_rng = container_of(rng, struct mxc_rng, rng);
 
-	ctrl = __raw_readl(rng_base + RNGA_CONTROL);
+	ctrl = __raw_readl(mxc_rng->mem + RNGA_CONTROL);
 
 	/* stop rnga */
-	__raw_writel(ctrl & ~RNGA_CONTROL_GO, rng_base + RNGA_CONTROL);
+	__raw_writel(ctrl & ~RNGA_CONTROL_GO, mxc_rng->mem + RNGA_CONTROL);
 }
 
-static struct hwrng mxc_rnga = {
-	.name = "mxc-rnga",
-	.init = mxc_rnga_init,
-	.cleanup = mxc_rnga_cleanup,
-	.data_present = mxc_rnga_data_present,
-	.data_read = mxc_rnga_data_read
-};
-
 static int __init mxc_rnga_probe(struct platform_device *pdev)
 {
 	int err = -ENODEV;
-	struct clk *clk;
 	struct resource *res, *mem;
-	void __iomem *rng_base = NULL;
-
-	if (rng_dev)
-		return -EBUSY;
-
-	clk = clk_get(&pdev->dev, NULL);
-	if (IS_ERR(clk)) {
+	struct mxc_rng *mxc_rng;
+
+	mxc_rng = devm_kzalloc(&pdev->dev, sizeof(struct mxc_rng),
+					GFP_KERNEL);
+	if (!mxc_rng)
+		return -ENOMEM;
+
+	mxc_rng->dev = &pdev->dev;
+	mxc_rng->rng.name = "mxc-rnga";
+	mxc_rng->rng.init = mxc_rnga_init;
+	mxc_rng->rng.cleanup = mxc_rnga_cleanup,
+	mxc_rng->rng.data_present = mxc_rnga_data_present,
+	mxc_rng->rng.data_read = mxc_rnga_data_read,
+
+	mxc_rng->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(mxc_rng->clk)) {
 		dev_err(&pdev->dev, "Could not get rng_clk!\n");
-		err = PTR_ERR(clk);
+		err = PTR_ERR(mxc_rng->clk);
 		goto out;
 	}
 
-	clk_prepare_enable(clk);
+	clk_prepare_enable(mxc_rng->clk);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
@@ -173,36 +178,27 @@ static int __init mxc_rnga_probe(struct platform_device *pdev)
 		goto err_region;
 	}
 
-	rng_base = ioremap(res->start, resource_size(res));
-	if (!rng_base) {
+	mxc_rng->mem = ioremap(res->start, resource_size(res));
+	if (!mxc_rng->mem) {
 		err = -ENOMEM;
 		goto err_ioremap;
 	}
 
-	mxc_rnga.priv = (unsigned long)rng_base;
-
-	err = hwrng_register(&mxc_rnga);
+	err = hwrng_register(&mxc_rng->rng);
 	if (err) {
 		dev_err(&pdev->dev, "MXC RNGA registering failed (%d)\n", err);
-		goto err_register;
+		goto err_ioremap;
 	}
 
-	rng_dev = pdev;
-
 	dev_info(&pdev->dev, "MXC RNGA Registered.\n");
 
 	return 0;
 
-err_register:
-	iounmap(rng_base);
-	rng_base = NULL;
-
 err_ioremap:
 	release_mem_region(res->start, resource_size(res));
 
 err_region:
-	clk_disable_unprepare(clk);
-	clk_put(clk);
+	clk_disable_unprepare(mxc_rng->clk);
 
 out:
 	return err;
@@ -211,17 +207,15 @@ out:
 static int __exit mxc_rnga_remove(struct platform_device *pdev)
 {
 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	void __iomem *rng_base = (void __iomem *)mxc_rnga.priv;
-	struct clk *clk = clk_get(&pdev->dev, NULL);
+	struct mxc_rng *mxc_rng = platform_get_drvdata(pdev);
 
-	hwrng_unregister(&mxc_rnga);
+	hwrng_unregister(&mxc_rng->rng);
 
-	iounmap(rng_base);
+	iounmap(mxc_rng->mem);
 
 	release_mem_region(res->start, resource_size(res));
 
-	clk_disable_unprepare(clk);
-	clk_put(clk);
+	clk_disable_unprepare(mxc_rng->clk);
 
 	return 0;
 }
-- 
1.7.1

Re: [PATCH v2 1/2] hw_random: mxc-rnga: Adapt clocks to new i.mx clock framework

[Sascha Hauer]

On Fri, Jul 27, 2012 at 01:47:51PM -0300, Fabio Estevam wrote:
> Adapt clocks to the new i.mx clock framework and fix the following warning:
> 
> Cc: Theodore Ts'o <tytso@mit.edu>
> Cc: Herbert Xu <herbert@gondor.apana.org.au> 
> Cc: <linux-kernel@vger.kernel.org>
> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>

Both:

Acked-by: Sascha Hauer <s.hauer@pengutronix.de>

Sascha

> ---
> Changes since v1:
> - Converted a missing 'clk_disable' to 'clk_disable_unprepare'
> 
>  drivers/char/hw_random/mxc-rnga.c |   10 +++++-----
>  1 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c
> index 85074de..62c7efe 100644
> --- a/drivers/char/hw_random/mxc-rnga.c
> +++ b/drivers/char/hw_random/mxc-rnga.c
> @@ -152,14 +152,14 @@ static int __init mxc_rnga_probe(struct platform_device *pdev)
>  	if (rng_dev)
>  		return -EBUSY;
>  
> -	clk = clk_get(&pdev->dev, "rng");
> +	clk = clk_get(&pdev->dev, NULL);
>  	if (IS_ERR(clk)) {
>  		dev_err(&pdev->dev, "Could not get rng_clk!\n");
>  		err = PTR_ERR(clk);
>  		goto out;
>  	}
>  
> -	clk_enable(clk);
> +	clk_prepare_enable(clk);
>  
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	if (!res) {
> @@ -201,7 +201,7 @@ err_ioremap:
>  	release_mem_region(res->start, resource_size(res));
>  
>  err_region:
> -	clk_disable(clk);
> +	clk_disable_unprepare(clk);
>  	clk_put(clk);
>  
>  out:
> @@ -212,7 +212,7 @@ static int __exit mxc_rnga_remove(struct platform_device *pdev)
>  {
>  	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	void __iomem *rng_base = (void __iomem *)mxc_rnga.priv;
> -	struct clk *clk = clk_get(&pdev->dev, "rng");
> +	struct clk *clk = clk_get(&pdev->dev, NULL);
>  
>  	hwrng_unregister(&mxc_rnga);
>  
> @@ -220,7 +220,7 @@ static int __exit mxc_rnga_remove(struct platform_device *pdev)
>  
>  	release_mem_region(res->start, resource_size(res));
>  
> -	clk_disable(clk);
> +	clk_disable_unprepare(clk);
>  	clk_put(clk);
>  
>  	return 0;
> -- 
> 1.7.1
> 
> 
> 

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH v2 1/2] hw_random: mxc-rnga: Adapt clocks to new i.mx clock framework

[Fabio Estevam]

Hi Herbert,

On Tue, Jul 31, 2012 at 3:40 AM, Sascha Hauer <s.hauer@pengutronix.de> wrote:
> On Fri, Jul 27, 2012 at 01:47:51PM -0300, Fabio Estevam wrote:
>> Adapt clocks to the new i.mx clock framework and fix the following warning:
>>
>> Cc: Theodore Ts'o <tytso@mit.edu>
>> Cc: Herbert Xu <herbert@gondor.apana.org.au>
>> Cc: <linux-kernel@vger.kernel.org>
>> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
>
> Both:
>
> Acked-by: Sascha Hauer <s.hauer@pengutronix.de>

Looks like git did not Cc'ed you in these patches.

Would it be OK to apply these two patches?

Thanks,

Fabio Estevam

Re: [PATCH v2 1/2] hw_random: mxc-rnga: Adapt clocks to new i.mx clock framework

[Fabio Estevam]

Herbert,

On Fri, Aug 3, 2012 at 12:10 PM, Fabio Estevam <festevam@gmail.com> wrote:
> Hi Herbert,
>
> On Tue, Jul 31, 2012 at 3:40 AM, Sascha Hauer <s.hauer@pengutronix.de> wrote:
>> On Fri, Jul 27, 2012 at 01:47:51PM -0300, Fabio Estevam wrote:
>>> Adapt clocks to the new i.mx clock framework and fix the following warning:
>>>
>>> Cc: Theodore Ts'o <tytso@mit.edu>
>>> Cc: Herbert Xu <herbert@gondor.apana.org.au>
>>> Cc: <linux-kernel@vger.kernel.org>
>>> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
>>
>> Both:
>>
>> Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
>
> Looks like git did not Cc'ed you in these patches.
>
> Would it be OK to apply these two patches?

Ping?

Re: [PATCH v2 1/2] hw_random: mxc-rnga: Adapt clocks to new i.mx clock framework

[Herbert Xu]

On Mon, Sep 03, 2012 at 06:08:45PM -0300, Fabio Estevam wrote:
> Herbert,
> 
> On Fri, Aug 3, 2012 at 12:10 PM, Fabio Estevam <festevam@gmail.com> wrote:
> > Hi Herbert,
> >
> > On Tue, Jul 31, 2012 at 3:40 AM, Sascha Hauer <s.hauer@pengutronix.de> wrote:
> >> On Fri, Jul 27, 2012 at 01:47:51PM -0300, Fabio Estevam wrote:
> >>> Adapt clocks to the new i.mx clock framework and fix the following warning:
> >>>
> >>> Cc: Theodore Ts'o <tytso@mit.edu>
> >>> Cc: Herbert Xu <herbert@gondor.apana.org.au>
> >>> Cc: <linux-kernel@vger.kernel.org>
> >>> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
> >>
> >> Both:
> >>
> >> Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
> >
> > Looks like git did not Cc'ed you in these patches.
> >
> > Would it be OK to apply these two patches?
> 
> Ping?

It would help if you actually send me the patches.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt