On Mon, Sep 01, 2014 at 07:11:44PM +0200, Arnd Bergmann wrote:

On Monday 01 September 2014 18:04:47 Catalin Marinas wrote:

quoted

On Mon, Sep 01, 2014 at 04:06:00PM +0100, Hanjun Guo wrote:

quoted

+#ifdef CONFIG_ACPI
+/* Configure some sensible defaults for ACPI mode */
+static int smsc911x_probe_config_acpi(struct smsc911x_platform_config *config,
+                                 acpi_handle *ahandle)
+{
+     if (!ahandle)
+             return -ENOSYS;
+
+     config->phy_interface = PHY_INTERFACE_MODE_MII;
+
+     config->flags |= SMSC911X_USE_32BIT;
+
+     config->irq_polarity = SMSC911X_IRQ_POLARITY_ACTIVE_HIGH;
+
+     config->irq_type = SMSC911X_IRQ_TYPE_PUSH_PULL;
+
+     return 0;
+}
+#else

I don't like this and it shows issues we have with ACPI on certain ARM
platforms. You hard-code these values to match the Juno platform. What
if we get another SoC which has different configuration here? For DT, we
have the smsc911x_probe_config_dt() which reads the relevant information
from DT. I think this kind of configuration would be more suitable as
_DSD properties and sharing the similar names with DT (but we go back to
the question about who's in charge of the _DSD properties).

Good point, I totally missed that.

There is of course the possibility to set those values based on the
acpi_device_id, but that is exactly the part that _DSD is trying to
avoid.

This will of course most likely be replaced by _DSD values. I just
hardcoded for now as _DSD is not yet in the kernel and issues around
maintenance of bindings are not solved (unless this happened at KS where
I was not present).

quoted

quoted

 static int smsc911x_drv_probe(struct platform_device *pdev)
 {
      struct device_node *np = pdev->dev.of_node;
+     acpi_handle *ahandle = ACPI_HANDLE(&pdev->dev);
      struct net_device *dev;
      struct smsc911x_data *pdata;
      struct smsc911x_platform_config *config = dev_get_platdata(&pdev->dev);

@@ -2436,6 +2464,9 @@ static int smsc911x_drv_probe(struct platform_device *pdev)
      }
 
      retval = smsc911x_probe_config_dt(&pdata->config, np);
+     if (retval)
+             retval = smsc911x_probe_config_acpi(&pdata->config, ahandle);
+

In most of the ACPI patches so far we check for ACPI first with DT as a
fall-back if ACPI is not enabled. This changes here.

Does this really make a difference?

quoted

I would prefer
something which probes only ACPI if the ACPI is enabled (run-time, not
config) otherwise DT only. E.g.

(example missing?)

I think we should have the equivalent of of_have_populated_dt(), to
check whether acpi is being used to boot, and have that new function
be hardcoded to zero in case of !IS_ENABLED(CONFIG_ACPI).

if (!acpi_disabled) is the equivalent if I understand you correctly.

But people until this point had expressed a preference for checking
.of_node and ACPI_HANDLE() to this point. This is obviously mutable
though depending on community preference.

Graeme