[PATCH 1/2] arc_emac: fix probe error path

[PATCH 1/2] arc_emac: fix probe error path

[Heiko Stübner]

The probe function at the moment only frees the netdev but does not disconnect
the phy or removes the mdio bus it registered.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
 drivers/net/ethernet/arc/emac_main.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index 9f45782..0cba97a 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -683,7 +683,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	priv->regs = devm_ioremap_resource(&pdev->dev, &res_regs);
 	if (IS_ERR(priv->regs)) {
 		err = PTR_ERR(priv->regs);
-		goto out;
+		goto out_netdev;
 	}
 	dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs);
 
@@ -693,7 +693,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
 		dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id);
 		err = -ENODEV;
-		goto out;
+		goto out_netdev;
 	}
 	dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id);
 
@@ -708,7 +708,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 			       ndev->name, ndev);
 	if (err) {
 		dev_err(&pdev->dev, "could not allocate IRQ\n");
-		goto out;
+		goto out_netdev;
 	}
 
 	/* Get MAC address from device tree */
@@ -729,7 +729,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	if (!priv->rxbd) {
 		dev_err(&pdev->dev, "failed to allocate data buffers\n");
 		err = -ENOMEM;
-		goto out;
+		goto out_netdev;
 	}
 
 	priv->txbd = priv->rxbd + RX_BD_NUM;
@@ -741,7 +741,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	err = arc_mdio_probe(pdev, priv);
 	if (err) {
 		dev_err(&pdev->dev, "failed to probe MII bus\n");
-		goto out;
+		goto out_netdev;
 	}
 
 	priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
@@ -749,7 +749,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	if (!priv->phy_dev) {
 		dev_err(&pdev->dev, "of_phy_connect() failed\n");
 		err = -ENODEV;
-		goto out;
+		goto out_mdio;
 	}
 
 	dev_info(&pdev->dev, "connected to %s phy with id 0x%x\n",
@@ -761,12 +761,18 @@ static int arc_emac_probe(struct platform_device *pdev)
 	if (err) {
 		netif_napi_del(&priv->napi);
 		dev_err(&pdev->dev, "failed to register network device\n");
-		goto out;
+		goto out_netif_api;
 	}
 
 	return 0;
 
-out:
+out_netif_api:
+	netif_napi_del(&priv->napi);
+	phy_disconnect(priv->phy_dev);
+	priv->phy_dev = NULL;
+out_mdio:
+	arc_mdio_remove(priv);
+out_netdev:
 	free_netdev(ndev);
 	return err;
 }
-- 
1.9.0

[PATCH 2/2] arc_emac: add clock handling

[Heiko Stübner]

This adds ability for the arc_emac to really handle its supplying clock.
To get the needed clock-frequency either a real clock or the previous
clock-frequency property must be provided.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---
 Documentation/devicetree/bindings/net/arc_emac.txt | 12 +++++-
 drivers/net/ethernet/arc/emac.h                    |  2 +
 drivers/net/ethernet/arc/emac_main.c               | 46 ++++++++++++++++------
 3 files changed, 47 insertions(+), 13 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/arc_emac.txt b/Documentation/devicetree/bindings/net/arc_emac.txt
index 7fbb027..a1d71eb 100644
--- a/Documentation/devicetree/bindings/net/arc_emac.txt
+++ b/Documentation/devicetree/bindings/net/arc_emac.txt
@@ -4,11 +4,15 @@ Required properties:
 - compatible: Should be "snps,arc-emac"
 - reg: Address and length of the register set for the device
 - interrupts: Should contain the EMAC interrupts
-- clock-frequency: CPU frequency. It is needed to calculate and set polling
-period of EMAC.
 - max-speed: see ethernet.txt file in the same directory.
 - phy: see ethernet.txt file in the same directory.
 
+Clock handling:
+The clock frequency is needed to calculate and set polling period of EMAC.
+It must be provided by one of:
+- clock-frequency: CPU frequency.
+- clocks: reference to the clock supplying the EMAC.
+
 Child nodes of the driver are the individual PHY devices connected to the
 MDIO bus. They must have a "reg" property given the PHY address on the MDIO bus.
 
@@ -19,7 +23,11 @@ Examples:
 		reg = <0xc0fc2000 0x3c>;
 		interrupts = <6>;
 		mac-address = [ 00 11 22 33 44 55 ];
+
 		clock-frequency = <80000000>;
+		/* or */
+		clocks = <&emac_clock>;
+
 		max-speed = <100>;
 		phy = <&phy0>;
 
diff --git a/drivers/net/ethernet/arc/emac.h b/drivers/net/ethernet/arc/emac.h
index 928fac6..53f85bf 100644
--- a/drivers/net/ethernet/arc/emac.h
+++ b/drivers/net/ethernet/arc/emac.h
@@ -11,6 +11,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/netdevice.h>
 #include <linux/phy.h>
+#include <linux/clk.h>
 
 /* STATUS and ENABLE Register bit masks */
 #define TXINT_MASK	(1<<0)	/* Transmit interrupt */
@@ -131,6 +132,7 @@ struct arc_emac_priv {
 	struct mii_bus *bus;
 
 	void __iomem *regs;
+	struct clk *clk;
 
 	struct napi_struct napi;
 	struct net_device_stats stats;
diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index 0cba97a..68f8ad5 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -649,13 +649,6 @@ static int arc_emac_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	/* Get CPU clock frequency from device tree */
-	if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
-				 &clock_frequency)) {
-		dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device tree\n");
-		return -EINVAL;
-	}
-
 	/* Get IRQ from device tree */
 	irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
 	if (!irq) {
@@ -687,13 +680,32 @@ static int arc_emac_probe(struct platform_device *pdev)
 	}
 	dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs);
 
+	priv->clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(priv->clk)) {
+		/* Get CPU clock frequency from device tree */
+		if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+					&clock_frequency)) {
+			dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device tree\n");
+			err = -EINVAL;
+			goto out_netdev;
+		}
+	} else {
+		err = clk_prepare_enable(priv->clk);
+		if (err) {
+			dev_err(&pdev->dev, "failed to enable clock\n");
+			goto out_clkget;
+		}
+
+		clock_frequency = clk_get_rate(priv->clk);
+	}
+
 	id = arc_reg_get(priv, R_ID);
 
 	/* Check for EMAC revision 5 or 7, magic number */
 	if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
 		dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id);
 		err = -ENODEV;
-		goto out_netdev;
+		goto out_clken;
 	}
 	dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id);
 
@@ -708,7 +720,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 			       ndev->name, ndev);
 	if (err) {
 		dev_err(&pdev->dev, "could not allocate IRQ\n");
-		goto out_netdev;
+		goto out_clken;
 	}
 
 	/* Get MAC address from device tree */
@@ -729,7 +741,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	if (!priv->rxbd) {
 		dev_err(&pdev->dev, "failed to allocate data buffers\n");
 		err = -ENOMEM;
-		goto out_netdev;
+		goto out_clken;
 	}
 
 	priv->txbd = priv->rxbd + RX_BD_NUM;
@@ -741,7 +753,7 @@ static int arc_emac_probe(struct platform_device *pdev)
 	err = arc_mdio_probe(pdev, priv);
 	if (err) {
 		dev_err(&pdev->dev, "failed to probe MII bus\n");
-		goto out_netdev;
+		goto out_clken;
 	}
 
 	priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
@@ -772,6 +784,12 @@ out_netif_api:
 	priv->phy_dev = NULL;
 out_mdio:
 	arc_mdio_remove(priv);
+out_clken:
+	if (IS_ERR(priv->clk))
+		clk_disable_unprepare(priv->clk);
+out_clkget:
+	if (IS_ERR(priv->clk))
+		clk_put(priv->clk);
 out_netdev:
 	free_netdev(ndev);
 	return err;
@@ -787,6 +805,12 @@ static int arc_emac_remove(struct platform_device *pdev)
 	arc_mdio_remove(priv);
 	unregister_netdev(ndev);
 	netif_napi_del(&priv->napi);
+
+	if (!IS_ERR(priv->clk)) {
+		clk_disable_unprepare(priv->clk);
+		clk_put(priv->clk);
+	}
+
 	free_netdev(ndev);
 
 	return 0;
-- 
1.9.0

Re: [PATCH 1/2] arc_emac: fix probe error path

[Max Schwarz]

On Wednesday 23 April 2014 at 14:21:55, Heiko Stübner wrote:
> The probe function at the moment only frees the netdev but does not
> disconnect the phy or removes the mdio bus it registered.
> 
> Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> ---
>  drivers/net/ethernet/arc/emac_main.c | 22 ++++++++++++++--------
>  1 file changed, 14 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/arc/emac_main.c
> b/drivers/net/ethernet/arc/emac_main.c index 9f45782..0cba97a 100644
> --- a/drivers/net/ethernet/arc/emac_main.c
> +++ b/drivers/net/ethernet/arc/emac_main.c
> @@ -683,7 +683,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	priv->regs = devm_ioremap_resource(&pdev->dev, &res_regs);
>  	if (IS_ERR(priv->regs)) {
>  		err = PTR_ERR(priv->regs);
> -		goto out;
> +		goto out_netdev;
>  	}
>  	dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs);
> 
> @@ -693,7 +693,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
>  		dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id);
>  		err = -ENODEV;
> -		goto out;
> +		goto out_netdev;
>  	}
>  	dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id);
> 
> @@ -708,7 +708,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  			       ndev->name, ndev);
>  	if (err) {
>  		dev_err(&pdev->dev, "could not allocate IRQ\n");
> -		goto out;
> +		goto out_netdev;
>  	}
> 
>  	/* Get MAC address from device tree */
> @@ -729,7 +729,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	if (!priv->rxbd) {
>  		dev_err(&pdev->dev, "failed to allocate data buffers\n");
>  		err = -ENOMEM;
> -		goto out;
> +		goto out_netdev;
>  	}
> 
>  	priv->txbd = priv->rxbd + RX_BD_NUM;
> @@ -741,7 +741,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	err = arc_mdio_probe(pdev, priv);
>  	if (err) {
>  		dev_err(&pdev->dev, "failed to probe MII bus\n");
> -		goto out;
> +		goto out_netdev;
>  	}
> 
>  	priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
> @@ -749,7 +749,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	if (!priv->phy_dev) {
>  		dev_err(&pdev->dev, "of_phy_connect() failed\n");
>  		err = -ENODEV;
> -		goto out;
> +		goto out_mdio;
>  	}
> 
>  	dev_info(&pdev->dev, "connected to %s phy with id 0x%x\n",
> @@ -761,12 +761,18 @@ static int arc_emac_probe(struct platform_device
> *pdev) if (err) {
>  		netif_napi_del(&priv->napi);

That line shouldn't be there anymore, right? You're doing netif_api_del() 
twice here.

>  		dev_err(&pdev->dev, "failed to register network device\n");
> -		goto out;
> +		goto out_netif_api;
>  	}
> 
>  	return 0;
> 
> -out:
> +out_netif_api:
> +	netif_napi_del(&priv->napi);
> +	phy_disconnect(priv->phy_dev);
> +	priv->phy_dev = NULL;
> +out_mdio:
> +	arc_mdio_remove(priv);
> +out_netdev:
>  	free_netdev(ndev);
>  	return err;
>  }

Everything else looks good.

Cheers,
  Max

Re: [PATCH 2/2] arc_emac: add clock handling

[Max Schwarz]

On Wednesday 23 April 2014 at 14:24:55, Heiko Stübner wrote:
> This adds ability for the arc_emac to really handle its supplying clock.
> To get the needed clock-frequency either a real clock or the previous
> clock-frequency property must be provided.
> 
> Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> ---
>  Documentation/devicetree/bindings/net/arc_emac.txt | 12 +++++-
>  drivers/net/ethernet/arc/emac.h                    |  2 +
>  drivers/net/ethernet/arc/emac_main.c               | 46
> ++++++++++++++++------ 3 files changed, 47 insertions(+), 13 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/net/arc_emac.txt
> b/Documentation/devicetree/bindings/net/arc_emac.txt index 7fbb027..a1d71eb
> 100644
> --- a/Documentation/devicetree/bindings/net/arc_emac.txt
> +++ b/Documentation/devicetree/bindings/net/arc_emac.txt
> @@ -4,11 +4,15 @@ Required properties:
>  - compatible: Should be "snps,arc-emac"
>  - reg: Address and length of the register set for the device
>  - interrupts: Should contain the EMAC interrupts
> -- clock-frequency: CPU frequency. It is needed to calculate and set polling
> -period of EMAC.
>  - max-speed: see ethernet.txt file in the same directory.
>  - phy: see ethernet.txt file in the same directory.
> 
> +Clock handling:
> +The clock frequency is needed to calculate and set polling period of EMAC.
> +It must be provided by one of:
> +- clock-frequency: CPU frequency.
> +- clocks: reference to the clock supplying the EMAC.
> +
>  Child nodes of the driver are the individual PHY devices connected to the
>  MDIO bus. They must have a "reg" property given the PHY address on the MDIO
> bus.
> 
> @@ -19,7 +23,11 @@ Examples:
>  		reg = <0xc0fc2000 0x3c>;
>  		interrupts = <6>;
>  		mac-address = [ 00 11 22 33 44 55 ];
> +
>  		clock-frequency = <80000000>;
> +		/* or */
> +		clocks = <&emac_clock>;
> +
>  		max-speed = <100>;
>  		phy = <&phy0>;
> 
> diff --git a/drivers/net/ethernet/arc/emac.h
> b/drivers/net/ethernet/arc/emac.h index 928fac6..53f85bf 100644
> --- a/drivers/net/ethernet/arc/emac.h
> +++ b/drivers/net/ethernet/arc/emac.h
> @@ -11,6 +11,7 @@
>  #include <linux/dma-mapping.h>
>  #include <linux/netdevice.h>
>  #include <linux/phy.h>
> +#include <linux/clk.h>
> 
>  /* STATUS and ENABLE Register bit masks */
>  #define TXINT_MASK	(1<<0)	/* Transmit interrupt */
> @@ -131,6 +132,7 @@ struct arc_emac_priv {
>  	struct mii_bus *bus;
> 
>  	void __iomem *regs;
> +	struct clk *clk;
> 
>  	struct napi_struct napi;
>  	struct net_device_stats stats;
> diff --git a/drivers/net/ethernet/arc/emac_main.c
> b/drivers/net/ethernet/arc/emac_main.c index 0cba97a..68f8ad5 100644
> --- a/drivers/net/ethernet/arc/emac_main.c
> +++ b/drivers/net/ethernet/arc/emac_main.c
> @@ -649,13 +649,6 @@ static int arc_emac_probe(struct platform_device *pdev)
> return -ENODEV;
>  	}
> 
> -	/* Get CPU clock frequency from device tree */
> -	if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
> -				 &clock_frequency)) {
> -		dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device
> tree\n"); -		return -EINVAL;
> -	}
> -
>  	/* Get IRQ from device tree */
>  	irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
>  	if (!irq) {
> @@ -687,13 +680,32 @@ static int arc_emac_probe(struct platform_device
> *pdev) }
>  	dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs);
> 
> +	priv->clk = of_clk_get(pdev->dev.of_node, 0);
> +	if (IS_ERR(priv->clk)) {
> +		/* Get CPU clock frequency from device tree */
> +		if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
> +					&clock_frequency)) {
> +			dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device
> tree\n"); +			err = -EINVAL;
> +			goto out_netdev;
> +		}
> +	} else {
> +		err = clk_prepare_enable(priv->clk);
> +		if (err) {
> +			dev_err(&pdev->dev, "failed to enable clock\n");
> +			goto out_clkget;
> +		}
> +
> +		clock_frequency = clk_get_rate(priv->clk);
> +	}
> +
>  	id = arc_reg_get(priv, R_ID);
> 
>  	/* Check for EMAC revision 5 or 7, magic number */
>  	if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
>  		dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id);
>  		err = -ENODEV;
> -		goto out_netdev;
> +		goto out_clken;
>  	}
>  	dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id);
> 
> @@ -708,7 +720,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  			       ndev->name, ndev);
>  	if (err) {
>  		dev_err(&pdev->dev, "could not allocate IRQ\n");
> -		goto out_netdev;
> +		goto out_clken;
>  	}
> 
>  	/* Get MAC address from device tree */
> @@ -729,7 +741,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	if (!priv->rxbd) {
>  		dev_err(&pdev->dev, "failed to allocate data buffers\n");
>  		err = -ENOMEM;
> -		goto out_netdev;
> +		goto out_clken;
>  	}
> 
>  	priv->txbd = priv->rxbd + RX_BD_NUM;
> @@ -741,7 +753,7 @@ static int arc_emac_probe(struct platform_device *pdev)
>  	err = arc_mdio_probe(pdev, priv);
>  	if (err) {
>  		dev_err(&pdev->dev, "failed to probe MII bus\n");
> -		goto out_netdev;
> +		goto out_clken;
>  	}
> 
>  	priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
> @@ -772,6 +784,12 @@ out_netif_api:
>  	priv->phy_dev = NULL;
>  out_mdio:
>  	arc_mdio_remove(priv);
> +out_clken:
> +	if (IS_ERR(priv->clk))
> +		clk_disable_unprepare(priv->clk);

Should be if (!IS_ERR(priv->clk)).

> +out_clkget:
> +	if (IS_ERR(priv->clk))
> +		clk_put(priv->clk);

The same.

>  out_netdev:
>  	free_netdev(ndev);
>  	return err;
> @@ -787,6 +805,12 @@ static int arc_emac_remove(struct platform_device
> *pdev) arc_mdio_remove(priv);
>  	unregister_netdev(ndev);
>  	netif_napi_del(&priv->napi);
> +
> +	if (!IS_ERR(priv->clk)) {
> +		clk_disable_unprepare(priv->clk);
> +		clk_put(priv->clk);
> +	}
> +
>  	free_netdev(ndev);
> 
>  	return 0;

Apart from that, the clock stuff has been

Tested-by: Max Schwarz <max.schwarz@online.de>
(on the same hardware, radxa rock)

Cheers,
  Max