Re: [PATCH net v2 2/3] drivers: net: cpsw: fix error messages when using phy-handle DT property
From: Grygorii Strashko
Date: Tue Apr 26 2016 - 03:50:47 EST
On 04/26/2016 12:55 AM, David Rivshin (Allworx) wrote:
On Mon, 25 Apr 2016 22:12:20 +0300
Grygorii Strashko <grygorii.strashko@xxxxxx> wrote:
On 04/22/2016 06:45 PM, David Rivshin (Allworx) wrote:
On Fri, 22 Apr 2016 16:03:34 +0300
Grygorii Strashko <grygorii.strashko@xxxxxx> wrote:
On 04/21/2016 09:26 PM, David Rivshin (Allworx) wrote:
From: David Rivshin <drivshin@xxxxxxxxxxx>
The phy-handle, phy_id, and fixed-link properties are mutually exclusive,
and only one need be specified. However if phy-handle was specified, an
error message would complain about the lack of phy_id or fixed-link.
I think, commit message need to be updated.
You not only fix log messages - you also fix the issue with
of_get_phy_mode(slave_node); which will not be called if phy-handle is used.
You are correct, and that is probably the more important fix compared
to the error messages.
Because the content is becoming less coherent, what I may do is split
this patch into 3 small patches:
A) devicetree binding documentation changes
B) cpsw_probe_dt changes, with the fixes for of_get_phy_mode() and
related error message
C) cpsw_slave_open changes, with the fixes for crash if of_phy_connect
returns NULL, and related error message
Does that sound reasonable?
Sounds reasonable for me.
Hope patch 1 from this series could be merged separately.
slave_data->phy_if = of_get_phy_mode(slave_node);
^ see below
Also, if phy-handle was specified and the subsequent of_phy_connect()
failed, the error message still referenced slaved->data->phy_id, which
would be empty. Instead, use the name of the device_node as a useful
identifier.
Fixes: 9e42f715264f ("drivers: net: cpsw: add phy-handle parsing")
Signed-off-by: David Rivshin <drivshin@xxxxxxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
Tested-by: Nicolas Chauvet <kwizart@xxxxxxxxx>
---
If would like this for -stable it should apply cleanly as far back
as 4.5. It failes on 4.4 due to some context differences, but can be
applied with 'git am -C2'. Or, I can produce a separate patch against
linux-4.4.y if preferred.
Changes since v1 [1]:
- Rebased (no conflicts)
- Added Tested-by from Nicolas Chauvet
- Added Acked-by from Rob Herring for the binding change
[1] https://patchwork.ozlabs.org/patch/560324/
Documentation/devicetree/bindings/net/cpsw.txt | 4 ++--
drivers/net/ethernet/ti/cpsw.c | 17 +++++++++++++----
2 files changed, 15 insertions(+), 6 deletions(-)
diff --git a/Documentation/devicetree/bindings/net/cpsw.txt b/Documentation/devicetree/bindings/net/cpsw.txt
index 28a4781..3033c0f 100644
--- a/Documentation/devicetree/bindings/net/cpsw.txt
+++ b/Documentation/devicetree/bindings/net/cpsw.txt
@@ -46,16 +46,16 @@ Optional properties:
- dual_emac_res_vlan : Specifies VID to be used to segregate the ports
- mac-address : See ethernet.txt file in the same directory
- phy_id : Specifies slave phy id
May be the "phy_id" can be marked as deprecated? (while here)
The recommended property now is "phy-handle".
I can certainly do that. Perhaps something like this?
- phy_id : Specifies slave phy id (deprecated, use phy-handle)
Rob, would you have any issues with bundling that?
- phy-handle : See ethernet.txt file in the same directory
Slave sub-nodes:
- fixed-link : See fixed-link.txt file in the same directory
- Either the property phy_id, or the sub-node
- fixed-link can be specified
+
+Note: Exactly one of phy_id, phy-handle, or fixed-link must be specified.
Note: "ti,hwmods" field is used to fetch the base address and irq
resources from TI, omap hwmod data base during device registration.
Future plan is to migrate hwmod data base contents into device tree
blob so that, all the required data will be used from device tree dts
file.
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index d69cb3f..3c81413 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1150,16 +1150,19 @@ static void cpsw_slave_open(struct cpsw_slave *slave, struct cpsw_priv *priv)
if (slave->data->phy_node)
slave->phy = of_phy_connect(priv->ndev, slave->data->phy_node,
&cpsw_adjust_link, 0, slave->data->phy_if);
else
slave->phy = phy_connect(priv->ndev, slave->data->phy_id,
&cpsw_adjust_link, slave->data->phy_if);
if (IS_ERR(slave->phy)) {
- dev_err(priv->dev, "phy %s not found on slave %d\n",
- slave->data->phy_id, slave->slave_num);
+ dev_err(priv->dev, "phy \"%s\" not found on slave %d\n",
+ slave->data->phy_node ?
+ slave->data->phy_node->full_name :
+ slave->data->phy_id,
+ slave->slave_num);
Unfortunately, there are some inconsistency between legacy and FDT API :(
of_phy_connect() will return valid phy_device or NULL, but phy_connect()
can return valid phy_device or ERR_PTR().
Good catch, I hadn't noticed that. It looks like that's actually a more
serious (pre-existing) bug: if of_phy_connect() returns NULL, we'd end
up dereferencing it and pagefaulting.
How about moving the IS_ERR() check into the phy_connect() case like this:
if (slave->data->phy_node) {
slave->phy = of_phy_connect(priv->ndev, slave->data->phy_node,
&cpsw_adjust_link, 0, slave->data->phy_if);
[1]
} else {
slave->phy = phy_connect(priv->ndev, slave->data->phy_id,
&cpsw_adjust_link, slave->data->phy_if);
if (IS_ERR(slave->phy))
slave->phy = NULL;
[2]
}
if (!slave->phy) {
dev_err(priv->dev, "phy \"%s\" not found on slave %d\n",
slave->data->phy_node ?
slave->data->phy_node->full_name :
slave->data->phy_id,
slave->slave_num);
} else {
Since you say the phy_id case is deprecated anyways, I'm not too concerned
about not printing the error code returned by phy_connect() in that case
(especially since it never did so in the past). That lets us still avoid
duplicating the dev_err() itself.
I'm not worry too much about duplicating dev_err() - it's always good to know
the reason of failure.
So, may be for of_phy_connect() [1]:
dev_err(priv->dev, "phy \"%s\" not found on slave %d\n",
slave->data->phy_node->full_name,
slave->slave_num);
and for phy_connect() [2]:
dev_err(priv->dev, "phy %s not found on slave %d, err %d\n",
slave->data->phy_id, slave->slave_num, PTR_ERR(slave->phy));
Mugunthan, any comments?
If that's the preference, then I can incorporate that into V3.
Yes, please, if no other comments.
--
regards,
-grygorii