diff mbox

[v3,3/3] ARM: amba: Properly handle devices with power domains

Message ID 1448976866-7892-4-git-send-email-m.szyprowski@samsung.com
State Superseded
Headers show

Commit Message

Marek Szyprowski Dec. 1, 2015, 1:34 p.m. UTC
To read pid/cid registers, the probed device need to be properly turned on.
When it is inside a power domain, the bus code should ensure that the
given power domain is enabled before trying to access device's registers.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

---
 drivers/amba/bus.c | 6 ++++++
 1 file changed, 6 insertions(+)

-- 
1.9.2

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Comments

Ulf Hansson Dec. 1, 2015, 3:29 p.m. UTC | #1
On 1 December 2015 at 14:34, Marek Szyprowski <m.szyprowski@samsung.com> wrote:
> To read pid/cid registers, the probed device need to be properly turned on.

> When it is inside a power domain, the bus code should ensure that the

> given power domain is enabled before trying to access device's registers.

>

> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>


Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>


Kind regards
Uffe

> ---

>  drivers/amba/bus.c | 6 ++++++

>  1 file changed, 6 insertions(+)

>

> diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c

> index 879a421..8d182a4 100644

> --- a/drivers/amba/bus.c

> +++ b/drivers/amba/bus.c

> @@ -365,6 +365,10 @@ static int amba_read_periphid(struct amba_device *dev)

>         if (!tmp)

>                 return -ENOMEM;

>

> +       ret = dev_pm_domain_attach(&dev->dev, true);

> +       if (ret == -EPROBE_DEFER)

> +               goto err_unmap;

> +

>         ret = amba_get_enable_pclk(dev);

>         if (ret == 0) {

>                 u32 pid, cid;

> @@ -389,6 +393,8 @@ static int amba_read_periphid(struct amba_device *dev)

>                         ret = -ENODEV;

>         }

>

> +       dev_pm_domain_detach(&dev->dev, true);

> +err_unmap:

>         iounmap(tmp);

>

>         return ret;

> --

> 1.9.2

>

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diff mbox

Patch

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 879a421..8d182a4 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -365,6 +365,10 @@  static int amba_read_periphid(struct amba_device *dev)
 	if (!tmp)
 		return -ENOMEM;
 
+	ret = dev_pm_domain_attach(&dev->dev, true);
+	if (ret == -EPROBE_DEFER)
+		goto err_unmap;
+
 	ret = amba_get_enable_pclk(dev);
 	if (ret == 0) {
 		u32 pid, cid;
@@ -389,6 +393,8 @@  static int amba_read_periphid(struct amba_device *dev)
 			ret = -ENODEV;
 	}
 
+	dev_pm_domain_detach(&dev->dev, true);
+err_unmap:
 	iounmap(tmp);
 
 	return ret;