[PATCH 0/4] Fix clocks for i.MX27 in mx2_camera.c

STALE5166d

8 messages, 3 authors, 2012-08-01 · open the first message on its own page

[PATCH 0/4] Fix clocks for i.MX27 in mx2_camera.c

From: Javier Martin <hidden>
Date: 2012-07-26 11:20:48

The following series follows the steps purposed by Guennadi
(http://www.spinics.net/lists/arm-kernel/msg185555.html) in
order to fix clock handlings for i.MX27 in mx2_camera.c

[PATCH 1/4] i.MX27: Fix emma-prp and csi clocks.
[PATCH 2/4] media: mx2_camera: Mark i.MX25 support as BROKEN.
[PATCH 3/4] Schedule removal of i.MX25 support in mx2_camera.c
[PATCH 4/4] media: mx2_camera: Fix clock handling for i.MX27.

[PATCH 1/4] i.MX27: Fix emma-prp and csi clocks.

From: Javier Martin <hidden>
Date: 2012-07-26 11:20:50

Naming of emma-prp related clocks for the i.MX27 is not correct.

Signed-off-by: Javier Martin <redacted>
---
 arch/arm/mach-imx/clk-imx27.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-imx/clk-imx27.c b/arch/arm/mach-imx/clk-imx27.c
index b1d343c..6e9cb02 100644
--- a/arch/arm/mach-imx/clk-imx27.c
+++ b/arch/arm/mach-imx/clk-imx27.c

@@ -223,7 +223,7 @@ int __init mx27_clocks_init(unsigned long fref)
 	clk_register_clkdev(clk[per3_gate], "per", "imx-fb.0");
 	clk_register_clkdev(clk[lcdc_ipg_gate], "ipg", "imx-fb.0");
 	clk_register_clkdev(clk[lcdc_ahb_gate], "ahb", "imx-fb.0");
-	clk_register_clkdev(clk[csi_ahb_gate], NULL, "mx2-camera.0");
+	clk_register_clkdev(clk[csi_ahb_gate], "ahb", "mx2-camera.0");
 	clk_register_clkdev(clk[usb_div], "per", "fsl-usb2-udc");
 	clk_register_clkdev(clk[usb_ipg_gate], "ipg", "fsl-usb2-udc");
 	clk_register_clkdev(clk[usb_ahb_gate], "ahb", "fsl-usb2-udc");

@@ -250,8 +250,10 @@ int __init mx27_clocks_init(unsigned long fref)
 	clk_register_clkdev(clk[i2c2_ipg_gate], NULL, "imx-i2c.1");
 	clk_register_clkdev(clk[owire_ipg_gate], NULL, "mxc_w1.0");
 	clk_register_clkdev(clk[kpp_ipg_gate], NULL, "imx-keypad");
-	clk_register_clkdev(clk[emma_ahb_gate], "ahb", "imx-emma");
-	clk_register_clkdev(clk[emma_ipg_gate], "ipg", "imx-emma");
+	clk_register_clkdev(clk[emma_ahb_gate], "emma-ahb", "mx2-camera.0");
+	clk_register_clkdev(clk[emma_ipg_gate], "emma-ipg", "mx2-camera.0");
+	clk_register_clkdev(clk[emma_ahb_gate], "ahb", "m2m-emmaprp.0");
+	clk_register_clkdev(clk[emma_ipg_gate], "ipg", "m2m-emmaprp.0");
 	clk_register_clkdev(clk[iim_ipg_gate], "iim", NULL);
 	clk_register_clkdev(clk[gpio_ipg_gate], "gpio", NULL);
 	clk_register_clkdev(clk[brom_ahb_gate], "brom", NULL);

-- 
1.7.9.5

[PATCH 2/4] media: mx2_camera: Mark i.MX25 support as BROKEN.

From: Javier Martin <hidden>
Date: 2012-07-26 11:20:52

i.MX25 support is known to have been broken for
almost a year.

Signed-off-by: Javier Martin <redacted>
---
 drivers/media/video/Kconfig |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index c0b9233..af9d2d0 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig

@@ -1136,7 +1136,7 @@ config VIDEO_MX2_HOSTSUPPORT
 
 config VIDEO_MX2
 	tristate "i.MX27/i.MX25 Camera Sensor Interface driver"
-	depends on VIDEO_DEV && SOC_CAMERA && (MACH_MX27 || ARCH_MX25)
+	depends on VIDEO_DEV && SOC_CAMERA && (MACH_MX27 || (ARCH_MX25 && BROKEN))
 	select VIDEOBUF2_DMA_CONTIG
 	select VIDEO_MX2_HOSTSUPPORT
 	---help---

-- 
1.7.9.5

[PATCH 3/4] Schedule removal of i.MX25 support in mx2_camera.c

From: Javier Martin <hidden>
Date: 2012-07-26 11:20:54

Support for i.MX25 in mx2_camera.c has been broken
for a year. Furthermore, i.MX25 video capture HW
doesn't have much in common with i.MX27. A separate
driver would be desirable.

Signed-off-by: Javier Martin <redacted>
---
 Documentation/feature-removal-schedule.txt |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 56000b3..6c50a17 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt

@@ -6,6 +6,15 @@ be removed from this file.  The suggested deprecation period is 3 releases.
 
 ---------------------------
 
+What:	support for i.mx25 in mx2_camera.c
+When:	v3.8
+Why:	it's been broken for a year. Furthermore, i.MX25 video capture
+	HW doesn't have much in common with i.MX27. A separate driver
+	will be needed for it.
+Who:	Javier Martin<javier.martin@vista-silicon.com>
+
+---------------------------
+
 What:	ddebug_query="query" boot cmdline param
 When:	v3.8
 Why:	obsoleted by dyndbg="query" and module.dyndbg="query"

-- 
1.7.9.5

[PATCH 4/4] media: mx2_camera: Fix clock handling for i.MX27.

From: Javier Martin <hidden>
Date: 2012-07-26 11:20:56

This driver wasn't converted to the new clock framework
(e038ed50a4a767add205094c035b6943e7b30140).

Signed-off-by: Javier Martin <redacted>
---
 drivers/media/video/mx2_camera.c |   67 ++++++++++++++++++++++----------------
 1 file changed, 39 insertions(+), 28 deletions(-)

diff --git a/drivers/media/video/mx2_camera.c b/drivers/media/video/mx2_camera.c
index 3c38b5f..88dcae6 100644
--- a/drivers/media/video/mx2_camera.c
+++ b/drivers/media/video/mx2_camera.c

@@ -273,7 +273,7 @@ struct mx2_camera_dev {
 	struct device		*dev;
 	struct soc_camera_host	soc_host;
 	struct soc_camera_device *icd;
-	struct clk		*clk_csi, *clk_emma;
+	struct clk		*clk_csi, *clk_emma_ahb, *clk_emma_ipg;
 
 	unsigned int		irq_csi, irq_emma;
 	void __iomem		*base_csi, *base_emma;

@@ -436,7 +436,8 @@ static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
 {
 	unsigned long flags;
 
-	clk_disable(pcdev->clk_csi);
+	if (cpu_is_mx27())
+		clk_disable_unprepare(pcdev->clk_csi);
 	writel(0, pcdev->base_csi + CSICR1);
 	if (cpu_is_mx27()) {
 		writel(0, pcdev->base_emma + PRP_CNTL);

@@ -464,9 +465,11 @@ static int mx2_camera_add_device(struct soc_camera_device *icd)
 	if (pcdev->icd)
 		return -EBUSY;
 
-	ret = clk_enable(pcdev->clk_csi);
-	if (ret < 0)
-		return ret;
+	if (cpu_is_mx27()) {
+		ret = clk_prepare_enable(pcdev->clk_csi);
+		if (ret < 0)
+			return ret;
+	}
 
 	csicr1 = CSICR1_MCLKEN;

@@ -1675,23 +1678,12 @@ static int __devinit mx27_camera_emma_init(struct mx2_camera_dev *pcdev)
 		goto exit_iounmap;
 	}
 
-	pcdev->clk_emma = clk_get(NULL, "emma");
-	if (IS_ERR(pcdev->clk_emma)) {
-		err = PTR_ERR(pcdev->clk_emma);
-		goto exit_free_irq;
-	}
-
-	clk_enable(pcdev->clk_emma);
-
 	err = mx27_camera_emma_prp_reset(pcdev);
 	if (err)
-		goto exit_clk_emma_put;
+		goto exit_free_irq;
 
 	return err;
 
-exit_clk_emma_put:
-	clk_disable(pcdev->clk_emma);
-	clk_put(pcdev->clk_emma);
 exit_free_irq:
 	free_irq(pcdev->irq_emma, pcdev);
 exit_iounmap:

@@ -1714,6 +1706,7 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
 
 	res_csi = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq_csi = platform_get_irq(pdev, 0);
+
 	if (res_csi == NULL || irq_csi < 0) {
 		dev_err(&pdev->dev, "Missing platform resources data\n");
 		err = -ENODEV;

@@ -1727,11 +1720,26 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
 		goto exit;
 	}
 
-	pcdev->clk_csi = clk_get(&pdev->dev, NULL);
-	if (IS_ERR(pcdev->clk_csi)) {
-		dev_err(&pdev->dev, "Could not get csi clock\n");
-		err = PTR_ERR(pcdev->clk_csi);
-		goto exit_kfree;
+	if (cpu_is_mx27()) {
+		pcdev->clk_csi = devm_clk_get(&pdev->dev, "ahb");
+		if (IS_ERR(pcdev->clk_csi)) {
+			dev_err(&pdev->dev, "Could not get csi clock\n");
+			err = PTR_ERR(pcdev->clk_csi);
+			goto exit_kfree;
+		}
+		pcdev->clk_emma_ipg = devm_clk_get(&pdev->dev, "emma-ipg");
+		if (IS_ERR(pcdev->clk_emma_ipg)) {
+			err = PTR_ERR(pcdev->clk_emma_ipg);
+			goto exit_kfree;
+		}
+		pcdev->clk_emma_ahb = devm_clk_get(&pdev->dev, "emma-ahb");
+		if (IS_ERR(pcdev->clk_emma_ahb)) {
+			err = PTR_ERR(pcdev->clk_emma_ahb);
+			goto exit_kfree;
+		}
+		clk_prepare_enable(pcdev->clk_csi);
+		clk_prepare_enable(pcdev->clk_emma_ipg);
+		clk_prepare_enable(pcdev->clk_emma_ahb);
 	}
 
 	pcdev->res_csi = res_csi;

@@ -1827,8 +1835,8 @@ exit_free_emma:
 eallocctx:
 	if (cpu_is_mx27()) {
 		free_irq(pcdev->irq_emma, pcdev);
-		clk_disable(pcdev->clk_emma);
-		clk_put(pcdev->clk_emma);
+		clk_disable_unprepare(pcdev->clk_emma_ipg);
+		clk_disable_unprepare(pcdev->clk_emma_ahb);
 		iounmap(pcdev->base_emma);
 		release_mem_region(pcdev->res_emma->start, resource_size(pcdev->res_emma));
 	}

@@ -1840,7 +1848,11 @@ exit_iounmap:
 exit_release:
 	release_mem_region(res_csi->start, resource_size(res_csi));
 exit_dma_free:
-	clk_put(pcdev->clk_csi);
+	if (cpu_is_mx27()) {
+		clk_disable_unprepare(pcdev->clk_emma_ipg);
+		clk_disable_unprepare(pcdev->clk_emma_ahb);
+		clk_disable_unprepare(pcdev->clk_csi);
+	}
 exit_kfree:
 	kfree(pcdev);
 exit:

@@ -1854,7 +1866,6 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
 			struct mx2_camera_dev, soc_host);
 	struct resource *res;
 
-	clk_put(pcdev->clk_csi);
 	if (cpu_is_mx25())
 		free_irq(pcdev->irq_csi, pcdev);
 	if (cpu_is_mx27())

@@ -1867,8 +1878,8 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
 	iounmap(pcdev->base_csi);
 
 	if (cpu_is_mx27()) {
-		clk_disable(pcdev->clk_emma);
-		clk_put(pcdev->clk_emma);
+		clk_disable_unprepare(pcdev->clk_emma_ipg);
+		clk_disable_unprepare(pcdev->clk_emma_ahb);
 		iounmap(pcdev->base_emma);
 		res = pcdev->res_emma;
 		release_mem_region(res->start, resource_size(res));

-- 
1.7.9.5

Re: [PATCH 4/4] media: mx2_camera: Fix clock handling for i.MX27.

From: Guennadi Liakhovetski <hidden>
Date: 2012-07-31 15:15:01

Hi Javier

Thanks for the patch. Let me try to understand what it is doing, please, 
correct any my mistakes.

On Thu, 26 Jul 2012, Javier Martin wrote:

quoted hunk

This driver wasn't converted to the new clock framework
(e038ed50a4a767add205094c035b6943e7b30140).

Signed-off-by: Javier Martin <redacted>
---
 drivers/media/video/mx2_camera.c |   67 ++++++++++++++++++++++----------------
 1 file changed, 39 insertions(+), 28 deletions(-)

diff --git a/drivers/media/video/mx2_camera.c b/drivers/media/video/mx2_camera.c
index 3c38b5f..88dcae6 100644
--- a/drivers/media/video/mx2_camera.c
+++ b/drivers/media/video/mx2_camera.c

@@ -273,7 +273,7 @@ struct mx2_camera_dev {
 	struct device		*dev;
 	struct soc_camera_host	soc_host;
 	struct soc_camera_device *icd;
-	struct clk		*clk_csi, *clk_emma;
+	struct clk		*clk_csi, *clk_emma_ahb, *clk_emma_ipg;
 
 	unsigned int		irq_csi, irq_emma;
 	void __iomem		*base_csi, *base_emma;

@@ -436,7 +436,8 @@ static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
 {
 	unsigned long flags;
 
-	clk_disable(pcdev->clk_csi);
+	if (cpu_is_mx27())
+		clk_disable_unprepare(pcdev->clk_csi);

This tells me, there are already 2 things going on here:

1. add clock-(un)prepare operations to enable / disable. Is this a problem 
atm? is the driver non-functional without this change or is it just an API 
correctness change? I thought you replied to this already, but 
unfortunately I couldn't find that your reply again, sorry.

2. use clocks only on i.MX27

quoted hunk

 	writel(0, pcdev->base_csi + CSICR1);
 	if (cpu_is_mx27()) {
 		writel(0, pcdev->base_emma + PRP_CNTL);

@@ -464,9 +465,11 @@ static int mx2_camera_add_device(struct soc_camera_device *icd)
 	if (pcdev->icd)
 		return -EBUSY;
 
-	ret = clk_enable(pcdev->clk_csi);
-	if (ret < 0)
-		return ret;
+	if (cpu_is_mx27()) {
+		ret = clk_prepare_enable(pcdev->clk_csi);
+		if (ret < 0)
+			return ret;
+	}

Same two as above.

quoted hunk

 
 	csicr1 = CSICR1_MCLKEN;

@@ -1675,23 +1678,12 @@ static int __devinit mx27_camera_emma_init(struct mx2_camera_dev *pcdev)
 		goto exit_iounmap;
 	}
 
-	pcdev->clk_emma = clk_get(NULL, "emma");
-	if (IS_ERR(pcdev->clk_emma)) {
-		err = PTR_ERR(pcdev->clk_emma);
-		goto exit_free_irq;
-	}
-
-	clk_enable(pcdev->clk_emma);
-
 	err = mx27_camera_emma_prp_reset(pcdev);
 	if (err)
-		goto exit_clk_emma_put;
+		goto exit_free_irq;
 
 	return err;
 
-exit_clk_emma_put:
-	clk_disable(pcdev->clk_emma);
-	clk_put(pcdev->clk_emma);
 exit_free_irq:
 	free_irq(pcdev->irq_emma, pcdev);
 exit_iounmap:
@@ -1714,6 +1706,7 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
 
 	res_csi = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq_csi = platform_get_irq(pdev, 0);
+
 	if (res_csi == NULL || irq_csi < 0) {
 		dev_err(&pdev->dev, "Missing platform resources data\n");
 		err = -ENODEV;
@@ -1727,11 +1720,26 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
 		goto exit;
 	}
 
-	pcdev->clk_csi = clk_get(&pdev->dev, NULL);
-	if (IS_ERR(pcdev->clk_csi)) {
-		dev_err(&pdev->dev, "Could not get csi clock\n");
-		err = PTR_ERR(pcdev->clk_csi);
-		goto exit_kfree;
+	if (cpu_is_mx27()) {
+		pcdev->clk_csi = devm_clk_get(&pdev->dev, "ahb");
+		if (IS_ERR(pcdev->clk_csi)) {
+			dev_err(&pdev->dev, "Could not get csi clock\n");
+			err = PTR_ERR(pcdev->clk_csi);
+			goto exit_kfree;
+		}
+		pcdev->clk_emma_ipg = devm_clk_get(&pdev->dev, "emma-ipg");
+		if (IS_ERR(pcdev->clk_emma_ipg)) {
+			err = PTR_ERR(pcdev->clk_emma_ipg);
+			goto exit_kfree;
+		}
+		pcdev->clk_emma_ahb = devm_clk_get(&pdev->dev, "emma-ahb");
+		if (IS_ERR(pcdev->clk_emma_ahb)) {
+			err = PTR_ERR(pcdev->clk_emma_ahb);
+			goto exit_kfree;
+		}
+		clk_prepare_enable(pcdev->clk_csi);
+		clk_prepare_enable(pcdev->clk_emma_ipg);
+		clk_prepare_enable(pcdev->clk_emma_ahb);
 	}
 
 	pcdev->res_csi = res_csi;

This does:

1. add clock-(un)prepare operations to enable / disable.

2. use clocks only on i.MX27

3. switch to managed clock requesting

4. groups clk_get(_devm)() and clk_prepare(_enable)() calls together

quoted hunk

@@ -1827,8 +1835,8 @@ exit_free_emma:
 eallocctx:
 	if (cpu_is_mx27()) {
 		free_irq(pcdev->irq_emma, pcdev);
-		clk_disable(pcdev->clk_emma);
-		clk_put(pcdev->clk_emma);
+		clk_disable_unprepare(pcdev->clk_emma_ipg);
+		clk_disable_unprepare(pcdev->clk_emma_ahb);
 		iounmap(pcdev->base_emma);
 		release_mem_region(pcdev->res_emma->start, resource_size(pcdev->res_emma));
 	}

@@ -1840,7 +1848,11 @@ exit_iounmap:
 exit_release:
 	release_mem_region(res_csi->start, resource_size(res_csi));
 exit_dma_free:
-	clk_put(pcdev->clk_csi);
+	if (cpu_is_mx27()) {
+		clk_disable_unprepare(pcdev->clk_emma_ipg);
+		clk_disable_unprepare(pcdev->clk_emma_ahb);
+		clk_disable_unprepare(pcdev->clk_csi);
+	}
 exit_kfree:
 	kfree(pcdev);
 exit:

@@ -1854,7 +1866,6 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
 			struct mx2_camera_dev, soc_host);
 	struct resource *res;
 
-	clk_put(pcdev->clk_csi);
 	if (cpu_is_mx25())
 		free_irq(pcdev->irq_csi, pcdev);
 	if (cpu_is_mx27())

@@ -1867,8 +1878,8 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
 	iounmap(pcdev->base_csi);
 
 	if (cpu_is_mx27()) {
-		clk_disable(pcdev->clk_emma);
-		clk_put(pcdev->clk_emma);
+		clk_disable_unprepare(pcdev->clk_emma_ipg);
+		clk_disable_unprepare(pcdev->clk_emma_ahb);
 		iounmap(pcdev->base_emma);
 		res = pcdev->res_emma;
 		release_mem_region(res->start, resource_size(res));

-- 
1.7.9.5

The rest adds to the implementation of the above 4 points.

So, if this is correct, my suggestion would be:

1. Don't make the CSI clock i.MX27-specific. You can do

-	pcdev->clk_csi = clk_get(&pdev->dev, NULL);
+	pcdev->clk_csi = clk_get(&pdev->dev, "ahb");

If NULL connection ID worked for i.MX25 before, using any non-empty string 
will work too.

2. I would rather not re-group clock requesting. It is not too unlogical, 
that mx27_camera_emma_init() allocates EMMA clocks. And keeping the CSI 
clock where it is would anyway make your grouping look less symmetric than 
in this version.

3. identify the real bug-fix portion of this patch and separate it from 
all other changes. Is the fix in using two separate "emma-ipg" and 
"emma-ahb" clocks instead of just a single "emma?" Or is prepare / 
unprepare also required? Please, make these to 1 or two _fix_ patches and 
the rest you can put in a clean-up / feature / improvement patch.

Does this make sense?

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

Re: [PATCH 4/4] media: mx2_camera: Fix clock handling for i.MX27.

From: Sascha Hauer <s.hauer@pengutronix.de>
Date: 2012-07-31 17:49:10

Hi Guennadi,

On Tue, Jul 31, 2012 at 05:14:25PM +0200, Guennadi Liakhovetski wrote:

Hi Javier

quoted

@@ -436,7 +436,8 @@ static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
 {
 	unsigned long flags;
 
-	clk_disable(pcdev->clk_csi);
+	if (cpu_is_mx27())
+		clk_disable_unprepare(pcdev->clk_csi);

This tells me, there are already 2 things going on here:

1. add clock-(un)prepare operations to enable / disable. Is this a problem 
atm? is the driver non-functional without this change or is it just an API 
correctness change? I thought you replied to this already, but 
unfortunately I couldn't find that your reply again, sorry.

Since the common clock framework clk_prepare is mandatory.

Sascha

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Re: [PATCH 4/4] media: mx2_camera: Fix clock handling for i.MX27.

From: Guennadi Liakhovetski <hidden>
Date: 2012-08-01 07:03:01

Hi Sascha

On Tue, 31 Jul 2012, Sascha Hauer wrote:

Hi Guennadi,

On Tue, Jul 31, 2012 at 05:14:25PM +0200, Guennadi Liakhovetski wrote:

quoted

Hi Javier

quoted

@@ -436,7 +436,8 @@ static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
 {
 	unsigned long flags;
 
-	clk_disable(pcdev->clk_csi);
+	if (cpu_is_mx27())
+		clk_disable_unprepare(pcdev->clk_csi);

This tells me, there are already 2 things going on here:

1. add clock-(un)prepare operations to enable / disable. Is this a problem 
atm? is the driver non-functional without this change or is it just an API 
correctness change? I thought you replied to this already, but 
unfortunately I couldn't find that your reply again, sorry.

Since the common clock framework clk_prepare is mandatory.

Good, thanks for the clarification. So, this is not a functional, but a 
correctness fix. I think, such fixes are acceptable after -rc1 until 
something like -rc5, but maybe not after that. So, I'd try to push this 
some time within the next couple of weeks, once I get this fix as a 
separate patch.

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

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