Re: [PATCH v5 2/2] phy: rockchip-inno-usb2: add a new driver for Rockchip usb2phy

From: Guenter Roeck
Date: Thu Jun 16 2016 - 09:12:47 EST


On 06/15/2016 06:47 PM, Frank Wang wrote:
Hi Guenter & Heiko,

On 2016/6/15 23:47, Guenter Roeck wrote:
On Tue, Jun 14, 2016 at 6:14 PM, Frank Wang <frank.wang@xxxxxxxxxxxxxx> wrote:
Hi Heiko & Guenter,


On 2016/6/14 22:00, Heiko StÃbner wrote:
Am Dienstag, 14. Juni 2016, 06:50:31 schrieb Guenter Roeck:
On Tue, Jun 14, 2016 at 6:27 AM, Heiko StÃbner <heiko@xxxxxxxxx> wrote:
Am Montag, 13. Juni 2016, 10:10:10 schrieb Frank Wang:
The newer SoCs (rk3366, rk3399) take a different usb-phy IP block
than rk3288 and before, and most of phy-related registers are also
different from the past, so a new phy driver is required necessarily.

Signed-off-by: Frank Wang <frank.wang@xxxxxxxxxxxxxx>
---
[...]

+static int rockchip_usb2phy_init(struct phy *phy)
+{
+ struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy);
+ struct rockchip_usb2phy *rphy = dev_get_drvdata(phy->dev.parent);
+ int ret;
+

if (!rport->port_cfg)
return 0;

Otherwise the currently empty otg-port will cause null-pointer
dereferences
when it gets assigned in the devicetree already.
Not really, at least not here - that port should not have port_id set
to USB2PHY_PORT_HOST.

Does it even make sense to instantiate the otg port ? Is it going to
do anything without port configuration ?
Ok, that would be the other option - not creating the phy in the driver.

Well, I will put this conditional inside *_host_port_init(), if it is an
empty, the phy-device should not be created.
Something like the following:

--- a/drivers/phy/phy-rockchip-inno-usb2.c
+++ b/drivers/phy/phy-rockchip-inno-usb2.c
@@ -483,9 +483,13 @@ static int rockchip_usb2phy_host_port_init(struct
rockchip_usb2phy *rphy,
{
int ret;

- rport->port_id = USB2PHY_PORT_HOST;
rport->port_cfg = &rphy->phy_cfg->port_cfgs[USB2PHY_PORT_HOST];
+ if (!rport->port_cfg) {
+ dev_err(rphy->dev, "no host port-config provided.\n");
+ return -EINVAL;
+ }
This would never be NULL. At issue is that you don't assign port_cfg
if the port is _not_ a host port.

Sorry, I made a mistake. How about something like the following:

Yes, that should work. Just keep in mind that there could always be
a port named "something-port", so you'll always need some kind of check
(and possibly return an error if a port with a wrong name is provided).

Thanks,
Guenter

@@ -574,6 +579,15 @@ static int rockchip_usb2phy_probe(struct platform_device *pdev)
struct rockchip_usb2phy_port *rport = &rphy->ports[index];
struct phy *phy;

+ /*
+ * This driver aim to support both otg-port and host-port,
+ * but unfortunately, the otg part is not ready in current,
+ * so this comments and below codes are interim, which should
+ * be removed after otg-port is supplied soon.
+ */
+ if (of_node_cmp(child_np->name, "host-port"))
+ goto next_child;
+
phy = devm_phy_create(dev, child_np, &rockchip_usb2phy_ops);
if (IS_ERR(phy)) {
dev_err(dev, "failed to create phy\n");
@@ -582,17 +596,13 @@ static int rockchip_usb2phy_probe(struct platform_device *pdev)
}

rport->phy = phy;
-
- /* initialize otg/host port separately */
- if (!of_node_cmp(child_np->name, "host-port")) {
- ret = rockchip_usb2phy_host_port_init(rphy, rport,
- child_np);
- if (ret)
- goto put_child;
- }
-
phy_set_drvdata(rport->phy, rport);

+ ret = rockchip_usb2phy_host_port_init(rphy, rport, child_np);
+ if (ret)
+ goto put_child;
+
+next_child:
/* to prevent out of boundary */
if (++index >= rphy->phy_cfg->num_ports)
break;


BR.
Frank