phy: tegra: fix device-tree node lookups

Fix child-node lookups during probe, which ended up searching the whole
device tree depth-first starting at the parents rather than just
matching on their children.

To make things worse, some parent nodes could end up being being
prematurely freed (by tegra_xusb_pad_register()) as
of_find_node_by_name() drops a reference to its first argument.

Fixes: 53d2a715c2 ("phy: Add Tegra XUSB pad controller support")
Cc: stable <stable@vger.kernel.org>     # 4.7
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
This commit is contained in:
Johan Hovold 2017-11-15 10:43:16 +01:00 committed by Kishon Vijay Abraham I
parent 4fbd8d194f
commit 046046737b

View file

@ -75,14 +75,14 @@ MODULE_DEVICE_TABLE(of, tegra_xusb_padctl_of_match);
static struct device_node *
tegra_xusb_find_pad_node(struct tegra_xusb_padctl *padctl, const char *name)
{
/*
* of_find_node_by_name() drops a reference, so make sure to grab one.
*/
struct device_node *np = of_node_get(padctl->dev->of_node);
struct device_node *pads, *np;
np = of_find_node_by_name(np, "pads");
if (np)
np = of_find_node_by_name(np, name);
pads = of_get_child_by_name(padctl->dev->of_node, "pads");
if (!pads)
return NULL;
np = of_get_child_by_name(pads, name);
of_node_put(pads);
return np;
}
@ -90,16 +90,16 @@ tegra_xusb_find_pad_node(struct tegra_xusb_padctl *padctl, const char *name)
static struct device_node *
tegra_xusb_pad_find_phy_node(struct tegra_xusb_pad *pad, unsigned int index)
{
/*
* of_find_node_by_name() drops a reference, so make sure to grab one.
*/
struct device_node *np = of_node_get(pad->dev.of_node);
struct device_node *np, *lanes;
np = of_find_node_by_name(np, "lanes");
if (!np)
lanes = of_get_child_by_name(pad->dev.of_node, "lanes");
if (!lanes)
return NULL;
return of_find_node_by_name(np, pad->soc->lanes[index].name);
np = of_get_child_by_name(lanes, pad->soc->lanes[index].name);
of_node_put(lanes);
return np;
}
static int
@ -195,7 +195,7 @@ int tegra_xusb_pad_register(struct tegra_xusb_pad *pad,
unsigned int i;
int err;
children = of_find_node_by_name(pad->dev.of_node, "lanes");
children = of_get_child_by_name(pad->dev.of_node, "lanes");
if (!children)
return -ENODEV;
@ -444,21 +444,21 @@ static struct device_node *
tegra_xusb_find_port_node(struct tegra_xusb_padctl *padctl, const char *type,
unsigned int index)
{
/*
* of_find_node_by_name() drops a reference, so make sure to grab one.
*/
struct device_node *np = of_node_get(padctl->dev->of_node);
struct device_node *ports, *np;
char *name;
np = of_find_node_by_name(np, "ports");
if (np) {
char *name;
ports = of_get_child_by_name(padctl->dev->of_node, "ports");
if (!ports)
return NULL;
name = kasprintf(GFP_KERNEL, "%s-%u", type, index);
if (!name)
return ERR_PTR(-ENOMEM);
np = of_find_node_by_name(np, name);
kfree(name);
name = kasprintf(GFP_KERNEL, "%s-%u", type, index);
if (!name) {
of_node_put(ports);
return ERR_PTR(-ENOMEM);
}
np = of_get_child_by_name(ports, name);
kfree(name);
of_node_put(ports);
return np;
}
@ -847,7 +847,7 @@ static void tegra_xusb_remove_ports(struct tegra_xusb_padctl *padctl)
static int tegra_xusb_padctl_probe(struct platform_device *pdev)
{
struct device_node *np = of_node_get(pdev->dev.of_node);
struct device_node *np = pdev->dev.of_node;
const struct tegra_xusb_padctl_soc *soc;
struct tegra_xusb_padctl *padctl;
const struct of_device_id *match;
@ -855,7 +855,7 @@ static int tegra_xusb_padctl_probe(struct platform_device *pdev)
int err;
/* for backwards compatibility with old device trees */
np = of_find_node_by_name(np, "pads");
np = of_get_child_by_name(np, "pads");
if (!np) {
dev_warn(&pdev->dev, "deprecated DT, using legacy driver\n");
return tegra_xusb_padctl_legacy_probe(pdev);