Re: [RFC] early init and DT platform devices allocation/registration
From: Hiroshi Doyu <hidden>
Date: 2013-06-28 08:49:15
Also in:
linux-tegra
Subsystem:
open firmware and flattened device tree, the rest · Maintainers:
Rob Herring, Saravana Kannan, Linus Torvalds
Possibly related (same subject, not in this thread)
- 2013-08-15 · Re: [RFC] early init and DT platform devices allocation/registration · Thierry Reding <hidden>
- 2013-06-28 · Re: [RFC] early init and DT platform devices allocation/registration · Grant Likely <hidden>
- 2013-06-28 · Re: [RFC] early init and DT platform devices allocation/registration · Thierry Reding <hidden>
- 2013-06-27 · Re: [RFC] early init and DT platform devices allocation/registration · Thierry Reding <hidden>
- 2013-06-26 · Re: [RFC] early init and DT platform devices allocation/registration · Grant Likely <hidden>
Grant Likely [off-list ref] wrote @ Wed, 26 Jun 2013 12:03:20 +0200:
On Wed, Jun 26, 2013 at 7:00 AM, Hiroshi Doyu [off-list ref] wrote:quoted
Grant Likely [off-list ref] wrote @ Tue, 25 Jun 2013 19:52:33 +0200:quoted
quoted
Here's my workaround. I need to call of_detach_node() with OF_DYNAMIC to avoid duplicated device registration.Gah! my eyes! Don't do that. It is incredibly problematic. Look at inhibiting duplicate device creation instead.I may not follow this thread correctly, but could anyone point out the above "inhibiting duplicate device creation" if there's already such solution?No, the solution doesn't exist yet, but it wouldn't be hard to implement. What you need to do is to add a struct device pointer to struct device_node, and set the pointer to the struct device when of_platform_device_create creates a device. (it would also need to be set for early_platform_device creation, but that's not something that should affect you). You would also add a check to of_platform_device_create to check if the device pointer is already set. If it is, then skip creation of the device.
Implemented as Grant suggested. At least this works for our case, where IOMMU needs to be instanciated earlier than other device[1]. early_platform_device case still need to be covered. [1] https://lists.ozlabs.org/pipermail/devicetree-discuss/2013-June/036685.html
From da563c72f7fc37fedd4b7e3a957f41a484a19788 Mon Sep 17 00:00:00 2001
From: Hiroshi Doyu <redacted> Date: Fri, 28 Jun 2013 11:43:20 +0300 Subject: [PATCH RFC 1/1] of: dev_node has struct device pointer To prevent of_platform_populate() from trying to populate duplicate devices if a device has been already populated. Signed-off-by: Hiroshi Doyu <redacted> --- drivers/of/base.c | 23 +++++++++++++++++++++++ drivers/of/platform.c | 8 ++++++++ include/linux/of.h | 16 ++++++++++++++++ 3 files changed, 47 insertions(+)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5c54279..99062dd 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c@@ -230,6 +230,29 @@ const void *of_get_property(const struct device_node *np, const char *name, } EXPORT_SYMBOL(of_get_property); +struct device *of_get_device(const struct device_node *node) +{ + struct device *dev; + unsigned long flags; + + raw_spin_lock_irqsave(&devtree_lock, flags); + dev = node->dev; + raw_spin_unlock_irqrestore(&devtree_lock, flags); + + return dev; +} +EXPORT_SYMBOL(of_get_device); + +void of_set_device(struct device_node *node, struct device *dev) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&devtree_lock, flags); + node->dev = dev; + raw_spin_unlock_irqrestore(&devtree_lock, flags); +} +EXPORT_SYMBOL(of_set_device); + /** Checks if the given "compat" string matches one of the strings in * the device's "compatible" property */
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index e0a6514..a8f6b09 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c@@ -203,10 +203,17 @@ struct platform_device *of_platform_device_create_pdata( struct device *parent) { struct platform_device *dev; + struct device *tmp; if (!of_device_is_available(np)) return NULL; + tmp = of_get_device(np); + if (tmp) { + dev_info(tmp, "Already populated\n"); + return to_platform_device(tmp); + } + dev = of_device_alloc(np, bus_id, parent); if (!dev) return NULL;
@@ -228,6 +235,7 @@ struct platform_device *of_platform_device_create_pdata( return NULL; } + of_set_device(np, &dev->dev); return dev; }
diff --git a/include/linux/of.h b/include/linux/of.h
index 1fd08ca..b548522 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h@@ -60,6 +60,9 @@ struct device_node { struct kref kref; unsigned long _flags; void *data; + + struct device *dev; /* Set only after populated */ + #if defined(CONFIG_SPARC) const char *path_component_name; unsigned int unique_id;
@@ -268,6 +271,8 @@ extern const void *of_get_property(const struct device_node *node, int *lenp); #define for_each_property_of_node(dn, pp) \ for (pp = dn->properties; pp != NULL; pp = pp->next) +extern struct device *of_get_device(const struct device_node *node); +extern void of_set_device(struct device_node *node, struct device *dev); extern int of_n_addr_cells(struct device_node *np); extern int of_n_size_cells(struct device_node *np);
@@ -459,6 +464,17 @@ static inline const void *of_get_property(const struct device_node *node, return NULL; } +static inline struct device *of_get_device(const struct device_node *node) +{ + return NULL; +} + +static inline void of_set_device(const struct device_node *node, + struct device *dev); +{ + return -ENOSYS; +} + static inline int of_property_read_u64(const struct device_node *np, const char *propname, u64 *out_value) {
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1.7.9.5