[PATCH 1/2] net: davinci_mdio: enable and disable clock

On Fri, Aug 03, 2012 at 10:52:40, Daniel Mack wrote:

On 03.08.2012 07:16, Vaibhav Hiremath wrote:

quoted

On 8/3/2012 1:13 AM, Daniel Mack wrote:

quoted

Make the driver control the device clocks. Appearantly, the Davinci
platform probes this driver with the clock all powered up, but on OMAP,
this isn't the case.

Signed-off-by: Daniel Mack <zonque@gmail.com>
---
 drivers/net/ethernet/ti/davinci_mdio.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c
index cd7ee20..b4b6015 100644
--- a/drivers/net/ethernet/ti/davinci_mdio.c
+++ b/drivers/net/ethernet/ti/davinci_mdio.c

@@ -332,6 +332,8 @@ static int __devinit davinci_mdio_probe(struct platform_device *pdev)
 		goto bail_out;
 	}
 
+	clk_enable(data->clk);
+
 	dev_set_drvdata(dev, data);
 	data->dev = dev;
 	spin_lock_init(&data->lock);

@@ -379,8 +381,11 @@ bail_out:
 	if (data->bus)
 		mdiobus_free(data->bus);
 
-	if (data->clk)
+	if (data->clk) {
+		clk_disable(data->clk);
 		clk_put(data->clk);
+	}
+
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 

@@ -397,8 +402,11 @@ static int __devexit davinci_mdio_remove(struct platform_device *pdev)
 	if (data->bus)
 		mdiobus_free(data->bus);
 
-	if (data->clk)
+	if (data->clk) {
+		clk_disable(data->clk);
 		clk_put(data->clk);
+	}
+
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 

@@ -427,6 +435,8 @@ static int davinci_mdio_suspend(struct device *dev)
 	data->suspended = true;
 	spin_unlock(&data->lock);
 
+	clk_disable(data->clk);
+
 	return 0;
 }
 

@@ -435,6 +445,8 @@ static int davinci_mdio_resume(struct device *dev)
 	struct davinci_mdio_data *data = dev_get_drvdata(dev);
 	u32 ctrl;
 
+	clk_enable(data->clk);
+

Danial,

I would request you to wait for this, its not that simple and straight.
And once you migrate to runtime PM you don't need clk_enable/disable,
this should get handled under runtime PM api's.

As I said, it can be dropped.

quoted

Also have you read my another email post -

http://comments.gmane.org/gmane.linux.ports.arm.omap/80796

Certainly, with respect to CPSW & MDIO, this patch is not enough and
requires further investigation. I have started looking at this and
hopefully will have some solution soon...

Ok, no problem. We certainly need the DT bindings for davinci_mdio. With
that applied, and the hwmod added (in the patch I posted yesterday), I
can at least mount the rootfs via NFS, which is all I currently need.

I certainly understand your requirement here.

Actually this is not the only device we have, the same issue is applicable 
to PWM subsystem available in AM335x. Hopefully I should have something soon 
on this.


Thanks,
Vaibhav