From 15c3597d6ea47e8f3caf068887c4666165df63ad Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Tue, 21 Jun 2011 10:59:35 -0600 Subject: [PATCH] dt/platform: allow device name to be overridden Some platform code has specific requirements on the naming of devices. This patch allows callers of of_platform_populate() to provide a device name lookup table. Signed-off-by: Grant Likely --- drivers/of/platform.c | 73 ++++++++++++++++++++++++++++++++----- include/linux/of_platform.h | 35 ++++++++++++++++++ 2 files changed, 98 insertions(+), 10 deletions(-) diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 4192ddc62638..e75af391e286 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -177,17 +177,20 @@ struct platform_device *of_device_alloc(struct device_node *np, EXPORT_SYMBOL(of_device_alloc); /** - * of_platform_device_create - Alloc, initialize and register an of_device + * of_platform_device_create_pdata - Alloc, initialize and register an of_device * @np: pointer to node to create device for * @bus_id: name to assign device + * @platform_data: pointer to populate platform_data pointer with * @parent: Linux device model parent device. * * Returns pointer to created platform device, or NULL if a device was not * registered. Unavailable devices will not get registered. */ -struct platform_device *of_platform_device_create(struct device_node *np, - const char *bus_id, - struct device *parent) +struct platform_device *of_platform_device_create_pdata( + struct device_node *np, + const char *bus_id, + void *platform_data, + struct device *parent) { struct platform_device *dev; @@ -203,6 +206,7 @@ struct platform_device *of_platform_device_create(struct device_node *np, #endif dev->dev.coherent_dma_mask = DMA_BIT_MASK(32); dev->dev.bus = &platform_bus_type; + dev->dev.platform_data = platform_data; /* We do not fill the DMA ops for platform devices by default. * This is currently the responsibility of the platform code @@ -216,6 +220,22 @@ struct platform_device *of_platform_device_create(struct device_node *np, return dev; } + +/** + * of_platform_device_create - Alloc, initialize and register an of_device + * @np: pointer to node to create device for + * @bus_id: name to assign device + * @parent: Linux device model parent device. + * + * Returns pointer to created platform device, or NULL if a device was not + * registered. Unavailable devices will not get registered. + */ +struct platform_device *of_platform_device_create(struct device_node *np, + const char *bus_id, + struct device *parent) +{ + return of_platform_device_create_pdata(np, bus_id, NULL, parent); +} EXPORT_SYMBOL(of_platform_device_create); #ifdef CONFIG_ARM_AMBA @@ -283,6 +303,28 @@ static struct amba_device *of_amba_device_create(struct device_node *node, } #endif /* CONFIG_ARM_AMBA */ +/** + * of_devname_lookup() - Given a device node, lookup the preferred Linux name + */ +static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup, + struct device_node *np) +{ + struct resource res; + if (lookup) { + for(; lookup->name != NULL; lookup++) { + if (!of_device_is_compatible(np, lookup->compatible)) + continue; + if (of_address_to_resource(np, 0, &res)) + continue; + if (res.start != lookup->phys_addr) + continue; + pr_debug("%s: devname=%s\n", np->full_name, lookup->name); + return lookup; + } + } + return NULL; +} + /** * of_platform_bus_create() - Create a device for a node and its children. * @bus: device node of the bus to instantiate @@ -295,10 +337,14 @@ static struct amba_device *of_amba_device_create(struct device_node *node, */ static int of_platform_bus_create(struct device_node *bus, const struct of_device_id *matches, + const struct of_dev_auxdata *lookup, struct device *parent, bool strict) { + const struct of_dev_auxdata *auxdata; struct device_node *child; struct platform_device *dev; + const char *bus_id = NULL; + void *platform_data = NULL; int rc = 0; /* Make sure it has a compatible property */ @@ -308,18 +354,24 @@ static int of_platform_bus_create(struct device_node *bus, return 0; } + auxdata = of_dev_lookup(lookup, bus); + if (auxdata) { + bus_id = auxdata->name; + platform_data = auxdata->platform_data; + } + if (of_device_is_compatible(bus, "arm,primecell")) { - of_amba_device_create(bus, NULL, NULL, parent); + of_amba_device_create(bus, bus_id, platform_data, parent); return 0; } - dev = of_platform_device_create(bus, NULL, parent); + dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent); if (!dev || !of_match_node(matches, bus)) return 0; for_each_child_of_node(bus, child) { pr_debug(" create child: %s\n", child->full_name); - rc = of_platform_bus_create(child, matches, &dev->dev, strict); + rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict); if (rc) { of_node_put(child); break; @@ -353,11 +405,11 @@ int of_platform_bus_probe(struct device_node *root, /* Do a self check of bus type, if there's a match, create children */ if (of_match_node(matches, root)) { - rc = of_platform_bus_create(root, matches, parent, false); + rc = of_platform_bus_create(root, matches, NULL, parent, false); } else for_each_child_of_node(root, child) { if (!of_match_node(matches, child)) continue; - rc = of_platform_bus_create(child, matches, parent, false); + rc = of_platform_bus_create(child, matches, NULL, parent, false); if (rc) break; } @@ -387,6 +439,7 @@ EXPORT_SYMBOL(of_platform_bus_probe); */ int of_platform_populate(struct device_node *root, const struct of_device_id *matches, + const struct of_dev_auxdata *lookup, struct device *parent) { struct device_node *child; @@ -397,7 +450,7 @@ int of_platform_populate(struct device_node *root, return -EINVAL; for_each_child_of_node(root, child) { - rc = of_platform_bus_create(child, matches, parent, true); + rc = of_platform_bus_create(child, matches, lookup, parent, true); if (rc) break; } diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index 839023351176..5a6f458a4bb7 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -19,6 +19,40 @@ #include #include +/** + * struct of_dev_auxdata - lookup table entry for device names & platform_data + * @compatible: compatible value of node to match against node + * @phys_addr: Start address of registers to match against node + * @name: Name to assign for matching nodes + * @platform_data: platform_data to assign for matching nodes + * + * This lookup table allows the caller of of_platform_populate() to override + * the names of devices when creating devices from the device tree. The table + * should be terminated with an empty entry. It also allows the platform_data + * pointer to be set. + * + * The reason for this functionality is that some Linux infrastructure uses + * the device name to look up a specific device, but the Linux-specific names + * are not encoded into the device tree, so the kernel needs to provide specific + * values. + * + * Note: Using an auxdata lookup table should be considered a last resort when + * converting a platform to use the DT. Normally the automatically generated + * device name will not matter, and drivers should obtain data from the device + * node instead of from an anonymouns platform_data pointer. + */ +struct of_dev_auxdata { + char *compatible; + resource_size_t phys_addr; + char *name; + void *platform_data; +}; + +/* Macro to simplify populating a lookup table */ +#define OF_DEV_AUXDATA(_compat,_phys,_name,_pdata) \ + { .compatible = _compat, .phys_addr = _phys, .name = _name, \ + .platform_data = _pdata } + /** * of_platform_driver - Legacy of-aware driver for platform devices. * @@ -59,6 +93,7 @@ extern int of_platform_bus_probe(struct device_node *root, struct device *parent); extern int of_platform_populate(struct device_node *root, const struct of_device_id *matches, + const struct of_dev_auxdata *lookup, struct device *parent); #endif /* !CONFIG_SPARC */ -- GitLab