Re: [PATCH RFC 3/4] xhci: Tune PHY for the DWC3-Exynos host controller

From: Heikki Krogerus
Date: Wed Apr 16 2014 - 10:13:00 EST


Hi,

On Tue, Apr 15, 2014 at 06:24:11PM +0530, Vivek Gautam wrote:
> I had seen your patches in the mailing list, but i don't see any
> updated version of these patches.
> Are you planning to work on this above mentioned patch-series any time soon ?

I'm sorry, I forgot this completely. I have not prepared new version
of those patches as the drivers I need them for are not ready yet, but
I guess I can also use this case as justification for them.

> Or, should i try to find a different approach for handling the phy
> from the host controller (child of DWC3 in this case, which has the
> phys).

Well, there is now an issue with the lookup method I'm suggesting in
this case. Since the device ID is now generated automatically for
xhci-hcd in dwc3, we don't know the xhci-hcd device name before
platform_device_add(), and that is too late. I don't see why the
device could not be named when platform_device_alloc() is called, so I
think I'll suggest something like the attached patch to fix this
issue.

In any case, I'll send an updated version of the phy patches soon.

Thanks,

--
heikki
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index e714709..13f8edb 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -169,11 +169,47 @@ struct platform_object {
*/
void platform_device_put(struct platform_device *pdev)
{
- if (pdev)
- put_device(&pdev->dev);
+ if (!pdev)
+ return;
+
+ if (pdev->id_auto) {
+ ida_simple_remove(&platform_devid_ida, pdev->id);
+ pdev->id = PLATFORM_DEVID_AUTO;
+ }
+
+ put_device(&pdev->dev);
}
EXPORT_SYMBOL_GPL(platform_device_put);

+static int pdev_set_name(struct platform_device *pdev)
+{
+ int ret;
+
+ switch (pdev->id) {
+ default:
+ dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
+ break;
+ case PLATFORM_DEVID_NONE:
+ dev_set_name(&pdev->dev, "%s", pdev->name);
+ break;
+ case PLATFORM_DEVID_AUTO:
+ /*
+ * Automatically allocated device ID. We mark it as such so
+ * that we remember it must be freed, and we append a suffix
+ * to avoid namespace collision with explicit IDs.
+ */
+ ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+ pdev->id = ret;
+ pdev->id_auto = true;
+ dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
+ break;
+ }
+
+ return 0;
+}
+
static void platform_device_release(struct device *dev)
{
struct platform_object *pa = container_of(dev, struct platform_object,
@@ -206,6 +242,10 @@ struct platform_device *platform_device_alloc(const char *name, int id)
device_initialize(&pa->pdev.dev);
pa->pdev.dev.release = platform_device_release;
arch_setup_pdev_archdata(&pa->pdev);
+ if (pdev_set_name(&pa->pdev)) {
+ kfree(pa);
+ return NULL;
+ }
}

return pa ? &pa->pdev : NULL;
@@ -286,28 +326,6 @@ int platform_device_add(struct platform_device *pdev)

pdev->dev.bus = &platform_bus_type;

- switch (pdev->id) {
- default:
- dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
- break;
- case PLATFORM_DEVID_NONE:
- dev_set_name(&pdev->dev, "%s", pdev->name);
- break;
- case PLATFORM_DEVID_AUTO:
- /*
- * Automatically allocated device ID. We mark it as such so
- * that we remember it must be freed, and we append a suffix
- * to avoid namespace collision with explicit IDs.
- */
- ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
- if (ret < 0)
- goto err_out;
- pdev->id = ret;
- pdev->id_auto = true;
- dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
- break;
- }
-
for (i = 0; i < pdev->num_resources; i++) {
struct resource *p, *r = &pdev->resource[i];

@@ -350,7 +368,6 @@ int platform_device_add(struct platform_device *pdev)
release_resource(r);
}

- err_out:
return ret;
}
EXPORT_SYMBOL_GPL(platform_device_add);
@@ -370,11 +387,6 @@ void platform_device_del(struct platform_device *pdev)
if (pdev) {
device_del(&pdev->dev);

- if (pdev->id_auto) {
- ida_simple_remove(&platform_devid_ida, pdev->id);
- pdev->id = PLATFORM_DEVID_AUTO;
- }
-
for (i = 0; i < pdev->num_resources; i++) {
struct resource *r = &pdev->resource[i];
unsigned long type = resource_type(r);
@@ -392,8 +404,15 @@ EXPORT_SYMBOL_GPL(platform_device_del);
*/
int platform_device_register(struct platform_device *pdev)
{
+ int ret;
+
device_initialize(&pdev->dev);
arch_setup_pdev_archdata(pdev);
+
+ ret = pdev_set_name(pdev);
+ if (ret)
+ return ret;
+
return platform_device_add(pdev);
}
EXPORT_SYMBOL_GPL(platform_device_register);