diff mbox series

[net-next,v2] net: dsa: mt7530: detect PHY muxing when PHY is defined on switch MDIO bus

Message ID 20240430-b4-for-netnext-mt7530-use-switch-mdio-bus-for-phy-muxing-v2-1-9104d886d0db@arinc9.com (mailing list archive)
State Accepted
Commit d8dcf5bd6d0eace9f7c1daa14b63b3925b09d033
Delegated to: Netdev Maintainers
Headers show
Series [net-next,v2] net: dsa: mt7530: detect PHY muxing when PHY is defined on switch MDIO bus | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 926 this patch: 926
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 15 of 15 maintainers
netdev/build_clang success Errors and warnings before: 937 this patch: 937
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 937 this patch: 937
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 9 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-05-01--06-00 (tests: 997)

Commit Message

Arınç ÜNAL via B4 Relay April 30, 2024, 5:01 a.m. UTC
From: Arınç ÜNAL <arinc.unal@arinc9.com>

Currently, the MT7530 DSA subdriver configures the MT7530 switch to provide
direct access to switch PHYs, meaning, the switch PHYs listen on the MDIO
bus the switch listens on. The PHY muxing feature makes use of this.

This is problematic as the PHY may be attached before the switch is
initialised, in which case, the PHY will fail to be attached.

Since commit 91374ba537bd ("net: dsa: mt7530: support OF-based registration
of switch MDIO bus"), we can describe the switch PHYs on the MDIO bus of
the switch on the device tree. Extend the check to detect PHY muxing when
the PHY is defined on the MDIO bus of the switch on the device tree.

When the PHY is described this way, the switch will be initialised first,
then the switch MDIO bus will be registered. Only after these steps, the
PHY will be attached.

Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
---
Changes in v2:
- Address the terminology on the patch log.
- Link to v1: https://lore.kernel.org/r/20240429-b4-for-netnext-mt7530-use-switch-mdio-bus-for-phy-muxing-v1-1-1f775983e155@arinc9.com
---
 drivers/net/dsa/mt7530.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)


---
base-commit: 5c4c0edca68a5841a8d53ccd49596fe199c8334c
change-id: 20240429-b4-for-netnext-mt7530-use-switch-mdio-bus-for-phy-muxing-586269371c55

Best regards,

Comments

Daniel Golle May 6, 2024, 11:24 a.m. UTC | #1
On Tue, Apr 30, 2024 at 08:01:33AM +0300, Arınç ÜNAL via B4 Relay wrote:
> From: Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> Currently, the MT7530 DSA subdriver configures the MT7530 switch to provide
> direct access to switch PHYs, meaning, the switch PHYs listen on the MDIO
> bus the switch listens on. The PHY muxing feature makes use of this.
> 
> This is problematic as the PHY may be attached before the switch is
> initialised, in which case, the PHY will fail to be attached.
> 
> Since commit 91374ba537bd ("net: dsa: mt7530: support OF-based registration
> of switch MDIO bus"), we can describe the switch PHYs on the MDIO bus of
> the switch on the device tree. Extend the check to detect PHY muxing when
> the PHY is defined on the MDIO bus of the switch on the device tree.
> 
> When the PHY is described this way, the switch will be initialised first,
> then the switch MDIO bus will be registered. Only after these steps, the
> PHY will be attached.
> 
> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>

Reviewed-by: Daniel Golle <daniel@makrotopia.org>

> ---
> Changes in v2:
> - Address the terminology on the patch log.
> - Link to v1: https://lore.kernel.org/r/20240429-b4-for-netnext-mt7530-use-switch-mdio-bus-for-phy-muxing-v1-1-1f775983e155@arinc9.com
> ---
>  drivers/net/dsa/mt7530.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
> index 2b9f904a98f0..6cf21c9d523b 100644
> --- a/drivers/net/dsa/mt7530.c
> +++ b/drivers/net/dsa/mt7530.c
> @@ -2483,7 +2483,8 @@ mt7530_setup(struct dsa_switch *ds)
>  			if (!phy_node)
>  				continue;
>  
> -			if (phy_node->parent == priv->dev->of_node->parent) {
> +			if (phy_node->parent == priv->dev->of_node->parent ||
> +			    phy_node->parent->parent == priv->dev->of_node) {

I had some concerns about missing check for phy_node->parent != NULL,
but it's impossible in practise. If phy_node exists, it will have a parent
node as well.

To be super extra safe, maybe doing
phy_node->parent && phy_node->parent->parent == priv->dev->of_node
would be better.

>  				ret = of_get_phy_mode(mac_np, &interface);
>  				if (ret && ret != -ENODEV) {
>  					of_node_put(mac_np);
> 
> ---
> base-commit: 5c4c0edca68a5841a8d53ccd49596fe199c8334c
> change-id: 20240429-b4-for-netnext-mt7530-use-switch-mdio-bus-for-phy-muxing-586269371c55
> 
> Best regards,
> -- 
> Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> 
>
Arınç ÜNAL May 7, 2024, 7:25 a.m. UTC | #2
On 06/05/2024 14:24, Daniel Golle wrote:
> On Tue, Apr 30, 2024 at 08:01:33AM +0300, Arınç ÜNAL via B4 Relay wrote:
>> From: Arınç ÜNAL <arinc.unal@arinc9.com>
>>
>> Currently, the MT7530 DSA subdriver configures the MT7530 switch to provide
>> direct access to switch PHYs, meaning, the switch PHYs listen on the MDIO
>> bus the switch listens on. The PHY muxing feature makes use of this.
>>
>> This is problematic as the PHY may be attached before the switch is
>> initialised, in which case, the PHY will fail to be attached.
>>
>> Since commit 91374ba537bd ("net: dsa: mt7530: support OF-based registration
>> of switch MDIO bus"), we can describe the switch PHYs on the MDIO bus of
>> the switch on the device tree. Extend the check to detect PHY muxing when
>> the PHY is defined on the MDIO bus of the switch on the device tree.
>>
>> When the PHY is described this way, the switch will be initialised first,
>> then the switch MDIO bus will be registered. Only after these steps, the
>> PHY will be attached.
>>
>> Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> Reviewed-by: Daniel Golle <daniel@makrotopia.org>
> 
>> ---
>> Changes in v2:
>> - Address the terminology on the patch log.
>> - Link to v1: https://lore.kernel.org/r/20240429-b4-for-netnext-mt7530-use-switch-mdio-bus-for-phy-muxing-v1-1-1f775983e155@arinc9.com
>> ---
>>   drivers/net/dsa/mt7530.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
>> index 2b9f904a98f0..6cf21c9d523b 100644
>> --- a/drivers/net/dsa/mt7530.c
>> +++ b/drivers/net/dsa/mt7530.c
>> @@ -2483,7 +2483,8 @@ mt7530_setup(struct dsa_switch *ds)
>>   			if (!phy_node)
>>   				continue;
>>   
>> -			if (phy_node->parent == priv->dev->of_node->parent) {
>> +			if (phy_node->parent == priv->dev->of_node->parent ||
>> +			    phy_node->parent->parent == priv->dev->of_node) {
> 
> I had some concerns about missing check for phy_node->parent != NULL,
> but it's impossible in practise. If phy_node exists, it will have a parent
> node as well.
> 
> To be super extra safe, maybe doing
> phy_node->parent && phy_node->parent->parent == priv->dev->of_node
> would be better.

At the current state of this driver where the hardware probes on OF, I
don't see any benefit of doing this so I'm going to pass on this for now.

Arınç
patchwork-bot+netdevbpf@kernel.org May 7, 2024, 9:40 a.m. UTC | #3
Hello:

This patch was applied to netdev/net-next.git (main)
by Paolo Abeni <pabeni@redhat.com>:

On Tue, 30 Apr 2024 08:01:33 +0300 you wrote:
> From: Arınç ÜNAL <arinc.unal@arinc9.com>
> 
> Currently, the MT7530 DSA subdriver configures the MT7530 switch to provide
> direct access to switch PHYs, meaning, the switch PHYs listen on the MDIO
> bus the switch listens on. The PHY muxing feature makes use of this.
> 
> This is problematic as the PHY may be attached before the switch is
> initialised, in which case, the PHY will fail to be attached.
> 
> [...]

Here is the summary with links:
  - [net-next,v2] net: dsa: mt7530: detect PHY muxing when PHY is defined on switch MDIO bus
    https://git.kernel.org/netdev/net-next/c/d8dcf5bd6d0e

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 2b9f904a98f0..6cf21c9d523b 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -2483,7 +2483,8 @@  mt7530_setup(struct dsa_switch *ds)
 			if (!phy_node)
 				continue;
 
-			if (phy_node->parent == priv->dev->of_node->parent) {
+			if (phy_node->parent == priv->dev->of_node->parent ||
+			    phy_node->parent->parent == priv->dev->of_node) {
 				ret = of_get_phy_mode(mac_np, &interface);
 				if (ret && ret != -ENODEV) {
 					of_node_put(mac_np);