generic: rtl836x: support defered probe on mdio-bus

On the WNDAP620, the mdio and mdc lines are controlled by
the EMAC ethernet device. This results in a hen-vs-egg problem.
The rtl8367b driver is probed before the ethernet driver and
the mdio-bus is not available yet, which caused the rtl8367b
driver to fail.

This patch changes the rtl8366_smi_probe_of() function to
return -EPROBE_DEFER if the mdio-bus lookup failed and changes
rtl8366_smi_probe()'s signature to return the error code back to
the callee, so it can propagate back to the kernel. Which, will
retry the switch probe at a later time.

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
This commit is contained in:
Christian Lamparter 2018-10-17 22:37:36 +02:00 committed by John Crispin
parent fb4bed5fe9
commit 910c2f9e68
5 changed files with 17 additions and 13 deletions

View file

@ -1553,8 +1553,8 @@ int rtl8366_smi_probe_of(struct platform_device *pdev, struct rtl8366_smi *smi)
smi->ext_mbus = of_mdio_find_bus(mdio_node);
if (!smi->ext_mbus) {
dev_err(&pdev->dev,
"cannot find mdio bus from bus handle");
dev_info(&pdev->dev,
"cannot find mdio bus from bus handle (yet)");
goto try_gpio;
}
@ -1562,8 +1562,12 @@ int rtl8366_smi_probe_of(struct platform_device *pdev, struct rtl8366_smi *smi)
try_gpio:
if (!gpio_is_valid(sck) || !gpio_is_valid(sda)) {
dev_err(&pdev->dev, "gpios missing in devictree\n");
return -EINVAL;
if (!mdio_node) {
dev_err(&pdev->dev, "gpios missing in devictree\n");
return -EINVAL;
} else {
return -EPROBE_DEFER;
}
}
smi->gpio_sda = sda;
@ -1619,7 +1623,7 @@ struct rtl8366_smi *rtl8366_smi_probe(struct platform_device *pdev)
free_smi:
kfree(smi);
return NULL;
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(rtl8366_smi_probe);

View file

@ -1445,8 +1445,8 @@ static int rtl8366rb_probe(struct platform_device *pdev)
" version " RTL8366RB_DRIVER_VER"\n");
smi = rtl8366_smi_probe(pdev);
if (!smi)
return -ENODEV;
if (IS_ERR(smi))
return PTR_ERR(smi);
smi->clk_delay = 10;
smi->cmd_read = 0xa9;

View file

@ -1233,8 +1233,8 @@ static int rtl8366s_probe(struct platform_device *pdev)
" version " RTL8366S_DRIVER_VER"\n");
smi = rtl8366_smi_probe(pdev);
if (!smi)
return -ENODEV;
if (IS_ERR(smi))
return PTR_ERR(smi);
smi->clk_delay = 10;
smi->cmd_read = 0xa9;

View file

@ -1752,8 +1752,8 @@ static int rtl8367_probe(struct platform_device *pdev)
int err;
smi = rtl8366_smi_probe(pdev);
if (!smi)
return -ENODEV;
if (IS_ERR(smi))
return PTR_ERR(smi);
smi->clk_delay = 1500;
smi->cmd_read = 0xb9;

View file

@ -1527,8 +1527,8 @@ static int rtl8367b_probe(struct platform_device *pdev)
int err;
smi = rtl8366_smi_probe(pdev);
if (!smi)
return -ENODEV;
if (IS_ERR(smi))
return PTR_ERR(smi);
smi->clk_delay = 1500;
smi->cmd_read = 0xb9;