From 5247aecfe62266ffdedf2fc9e4243638554455b6 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 27 Mar 2009 21:50:00 +0800 Subject: driver core: fix driver_match_device This patch fixes a bug introduced in commit 49b420a13ff95b449947181190b08367348e3e1b. If a instance of bus_type doesn't have .match method, all .probe of drivers in the bus should be called, or else the .probe have not a chance to be called. Signed-off-by: Ming Lei Reported-by: Guennadi Liakhovetski Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/base.h b/drivers/base/base.h index ddc97496db4a..b528145a078f 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -115,7 +115,7 @@ extern int driver_probe_device(struct device_driver *drv, struct device *dev); static inline int driver_match_device(struct device_driver *drv, struct device *dev) { - return drv->bus->match && drv->bus->match(dev, drv); + return drv->bus->match ? drv->bus->match(dev, drv) : 1; } extern void sysdev_shutdown(void); -- cgit v1.2.3 From 13977091a988fb0d21821c2221ddc920eba36b79 Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Mon, 30 Mar 2009 14:37:25 -0700 Subject: Driver Core: early platform driver V3 of the early platform driver implementation. Platform drivers are great for embedded platforms because we can separate driver configuration from the actual driver. So base addresses, interrupts and other configuration can be kept with the processor or board code, and the platform driver can be reused by many different platforms. For early devices we have nothing today. For instance, to configure early timers and early serial ports we cannot use platform devices. This because the setup order during boot. Timers are needed before the platform driver core code is available. The same goes for early printk support. Early in this case means before initcalls. These early drivers today have their configuration either hard coded or they receive it using some special configuration method. This is working quite well, but if we want to support both regular kernel modules and early devices then we need to have two ways of configuring the same driver. A single way would be better. The early platform driver patch is basically a set of functions that allow drivers to register themselves and architecture code to locate them and probe. Registration happens through early_param(). The time for the probe is decided by the architecture code. See Documentation/driver-model/platform.txt for more details. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Magnus Damm Cc: Paul Mundt Cc: Kay Sievers Cc: David Brownell Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- Documentation/driver-model/platform.txt | 59 ++++++++ drivers/base/platform.c | 239 ++++++++++++++++++++++++++++++++ include/linux/init.h | 1 + include/linux/platform_device.h | 42 ++++++ init/main.c | 7 +- 5 files changed, 347 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/Documentation/driver-model/platform.txt b/Documentation/driver-model/platform.txt index 83009fdcbbc8..2e2c2ea90ceb 100644 --- a/Documentation/driver-model/platform.txt +++ b/Documentation/driver-model/platform.txt @@ -169,3 +169,62 @@ three different ways to find such a match: be probed later if another device registers. (Which is OK, since this interface is only for use with non-hotpluggable devices.) + +Early Platform Devices and Drivers +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The early platform interfaces provide platform data to platform device +drivers early on during the system boot. The code is built on top of the +early_param() command line parsing and can be executed very early on. + +Example: "earlyprintk" class early serial console in 6 steps + +1. Registering early platform device data +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The architecture code registers platform device data using the function +early_platform_add_devices(). In the case of early serial console this +should be hardware configuration for the serial port. Devices registered +at this point will later on be matched against early platform drivers. + +2. Parsing kernel command line +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The architecture code calls parse_early_param() to parse the kernel +command line. This will execute all matching early_param() callbacks. +User specified early platform devices will be registered at this point. +For the early serial console case the user can specify port on the +kernel command line as "earlyprintk=serial.0" where "earlyprintk" is +the class string, "serial" is the name of the platfrom driver and +0 is the platform device id. If the id is -1 then the dot and the +id can be omitted. + +3. Installing early platform drivers belonging to a certain class +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The architecture code may optionally force registration of all early +platform drivers belonging to a certain class using the function +early_platform_driver_register_all(). User specified devices from +step 2 have priority over these. This step is omitted by the serial +driver example since the early serial driver code should be disabled +unless the user has specified port on the kernel command line. + +4. Early platform driver registration +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Compiled-in platform drivers making use of early_platform_init() are +automatically registered during step 2 or 3. The serial driver example +should use early_platform_init("earlyprintk", &platform_driver). + +5. Probing of early platform drivers belonging to a certain class +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The architecture code calls early_platform_driver_probe() to match +registered early platform devices associated with a certain class with +registered early platform drivers. Matched devices will get probed(). +This step can be executed at any point during the early boot. As soon +as possible may be good for the serial port case. + +6. Inside the early platform driver probe() +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The driver code needs to take special care during early boot, especially +when it comes to memory allocation and interrupt registration. The code +in the probe() function can use is_early_platform_device() to check if +it is called at early platform device or at the regular platform device +time. The early serial driver performs register_console() at this point. + +For further information, see . diff --git a/drivers/base/platform.c b/drivers/base/platform.c index d2198f64ad4e..b5b6c973a2e0 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -990,6 +990,8 @@ int __init platform_bus_init(void) { int error; + early_platform_cleanup(); + error = device_register(&platform_bus); if (error) return error; @@ -1020,3 +1022,240 @@ u64 dma_get_required_mask(struct device *dev) } EXPORT_SYMBOL_GPL(dma_get_required_mask); #endif + +static __initdata LIST_HEAD(early_platform_driver_list); +static __initdata LIST_HEAD(early_platform_device_list); + +/** + * early_platform_driver_register + * @edrv: early_platform driver structure + * @buf: string passed from early_param() + */ +int __init early_platform_driver_register(struct early_platform_driver *epdrv, + char *buf) +{ + unsigned long index; + int n; + + /* Simply add the driver to the end of the global list. + * Drivers will by default be put on the list in compiled-in order. + */ + if (!epdrv->list.next) { + INIT_LIST_HEAD(&epdrv->list); + list_add_tail(&epdrv->list, &early_platform_driver_list); + } + + /* If the user has specified device then make sure the driver + * gets prioritized. The driver of the last device specified on + * command line will be put first on the list. + */ + n = strlen(epdrv->pdrv->driver.name); + if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) { + list_move(&epdrv->list, &early_platform_driver_list); + + if (!strcmp(buf, epdrv->pdrv->driver.name)) + epdrv->requested_id = -1; + else if (buf[n] == '.' && strict_strtoul(&buf[n + 1], 10, + &index) == 0) + epdrv->requested_id = index; + else + epdrv->requested_id = EARLY_PLATFORM_ID_ERROR; + } + + return 0; +} + +/** + * early_platform_add_devices - add a numbers of early platform devices + * @devs: array of early platform devices to add + * @num: number of early platform devices in array + */ +void __init early_platform_add_devices(struct platform_device **devs, int num) +{ + struct device *dev; + int i; + + /* simply add the devices to list */ + for (i = 0; i < num; i++) { + dev = &devs[i]->dev; + + if (!dev->devres_head.next) { + INIT_LIST_HEAD(&dev->devres_head); + list_add_tail(&dev->devres_head, + &early_platform_device_list); + } + } +} + +/** + * early_platform_driver_register_all + * @class_str: string to identify early platform driver class + */ +void __init early_platform_driver_register_all(char *class_str) +{ + /* The "class_str" parameter may or may not be present on the kernel + * command line. If it is present then there may be more than one + * matching parameter. + * + * Since we register our early platform drivers using early_param() + * we need to make sure that they also get registered in the case + * when the parameter is missing from the kernel command line. + * + * We use parse_early_options() to make sure the early_param() gets + * called at least once. The early_param() may be called more than + * once since the name of the preferred device may be specified on + * the kernel command line. early_platform_driver_register() handles + * this case for us. + */ + parse_early_options(class_str); +} + +/** + * early_platform_match + * @edrv: early platform driver structure + * @id: id to match against + */ +static __init struct platform_device * +early_platform_match(struct early_platform_driver *epdrv, int id) +{ + struct platform_device *pd; + + list_for_each_entry(pd, &early_platform_device_list, dev.devres_head) + if (platform_match(&pd->dev, &epdrv->pdrv->driver)) + if (pd->id == id) + return pd; + + return NULL; +} + +/** + * early_platform_left + * @edrv: early platform driver structure + * @id: return true if id or above exists + */ +static __init int early_platform_left(struct early_platform_driver *epdrv, + int id) +{ + struct platform_device *pd; + + list_for_each_entry(pd, &early_platform_device_list, dev.devres_head) + if (platform_match(&pd->dev, &epdrv->pdrv->driver)) + if (pd->id >= id) + return 1; + + return 0; +} + +/** + * early_platform_driver_probe_id + * @class_str: string to identify early platform driver class + * @id: id to match against + * @nr_probe: number of platform devices to successfully probe before exiting + */ +static int __init early_platform_driver_probe_id(char *class_str, + int id, + int nr_probe) +{ + struct early_platform_driver *epdrv; + struct platform_device *match; + int match_id; + int n = 0; + int left = 0; + + list_for_each_entry(epdrv, &early_platform_driver_list, list) { + /* only use drivers matching our class_str */ + if (strcmp(class_str, epdrv->class_str)) + continue; + + if (id == -2) { + match_id = epdrv->requested_id; + left = 1; + + } else { + match_id = id; + left += early_platform_left(epdrv, id); + + /* skip requested id */ + switch (epdrv->requested_id) { + case EARLY_PLATFORM_ID_ERROR: + case EARLY_PLATFORM_ID_UNSET: + break; + default: + if (epdrv->requested_id == id) + match_id = EARLY_PLATFORM_ID_UNSET; + } + } + + switch (match_id) { + case EARLY_PLATFORM_ID_ERROR: + pr_warning("%s: unable to parse %s parameter\n", + class_str, epdrv->pdrv->driver.name); + /* fall-through */ + case EARLY_PLATFORM_ID_UNSET: + match = NULL; + break; + default: + match = early_platform_match(epdrv, match_id); + } + + if (match) { + if (epdrv->pdrv->probe(match)) + pr_warning("%s: unable to probe %s early.\n", + class_str, match->name); + else + n++; + } + + if (n >= nr_probe) + break; + } + + if (left) + return n; + else + return -ENODEV; +} + +/** + * early_platform_driver_probe + * @class_str: string to identify early platform driver class + * @nr_probe: number of platform devices to successfully probe before exiting + * @user_only: only probe user specified early platform devices + */ +int __init early_platform_driver_probe(char *class_str, + int nr_probe, + int user_only) +{ + int k, n, i; + + n = 0; + for (i = -2; n < nr_probe; i++) { + k = early_platform_driver_probe_id(class_str, i, nr_probe - n); + + if (k < 0) + break; + + n += k; + + if (user_only) + break; + } + + return n; +} + +/** + * early_platform_cleanup - clean up early platform code + */ +void __init early_platform_cleanup(void) +{ + struct platform_device *pd, *pd2; + + /* clean up the devres list used to chain devices */ + list_for_each_entry_safe(pd, pd2, &early_platform_device_list, + dev.devres_head) { + list_del(&pd->dev.devres_head); + memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head)); + } +} + diff --git a/include/linux/init.h b/include/linux/init.h index 68cb0265d009..f121a7a10c3d 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -247,6 +247,7 @@ struct obs_kernel_param { /* Relies on boot_command_line being set */ void __init parse_early_param(void); +void __init parse_early_options(char *cmdline); #endif /* __ASSEMBLY__ */ /** diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 76e470a299bf..72736fd8223c 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -77,4 +77,46 @@ extern int platform_driver_probe(struct platform_driver *driver, #define platform_get_drvdata(_dev) dev_get_drvdata(&(_dev)->dev) #define platform_set_drvdata(_dev,data) dev_set_drvdata(&(_dev)->dev, (data)) +/* early platform driver interface */ +struct early_platform_driver { + const char *class_str; + struct platform_driver *pdrv; + struct list_head list; + int requested_id; +}; + +#define EARLY_PLATFORM_ID_UNSET -2 +#define EARLY_PLATFORM_ID_ERROR -3 + +extern int early_platform_driver_register(struct early_platform_driver *epdrv, + char *buf); +extern void early_platform_add_devices(struct platform_device **devs, int num); + +static inline int is_early_platform_device(struct platform_device *pdev) +{ + return !pdev->dev.driver; +} + +extern void early_platform_driver_register_all(char *class_str); +extern int early_platform_driver_probe(char *class_str, + int nr_probe, int user_only); +extern void early_platform_cleanup(void); + + +#ifndef MODULE +#define early_platform_init(class_string, platform_driver) \ +static __initdata struct early_platform_driver early_driver = { \ + .class_str = class_string, \ + .pdrv = platform_driver, \ + .requested_id = EARLY_PLATFORM_ID_UNSET, \ +}; \ +static int __init early_platform_driver_setup_func(char *buf) \ +{ \ + return early_platform_driver_register(&early_driver, buf); \ +} \ +early_param(class_string, early_platform_driver_setup_func) +#else /* MODULE */ +#define early_platform_init(class_string, platform_driver) +#endif /* MODULE */ + #endif /* _PLATFORM_DEVICE_H_ */ diff --git a/init/main.c b/init/main.c index 3585f073d636..3bbf93be744c 100644 --- a/init/main.c +++ b/init/main.c @@ -492,6 +492,11 @@ static int __init do_early_param(char *param, char *val) return 0; } +void __init parse_early_options(char *cmdline) +{ + parse_args("early options", cmdline, NULL, 0, do_early_param); +} + /* Arch code calls this early on, or if not, just before other parsing. */ void __init parse_early_param(void) { @@ -503,7 +508,7 @@ void __init parse_early_param(void) /* All fall through to do_early_param. */ strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); - parse_args("early options", tmp_cmdline, NULL, 0, do_early_param); + parse_early_options(tmp_cmdline); done = 1; } -- cgit v1.2.3 From 014c90dbb9b63bae067afc80a7931a76c5268ae3 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 15 Apr 2009 16:00:12 -0700 Subject: driver core: prevent device_for_each_child from oopsing David Vrabel noticed that the wireless usb stack likes to call device_for_each_chile() with an empty bus. This used to work fine, but now oopses. This patch fixes the oops and makes the code behave like it used to. Reported-by: David Vrabel Tested-by: David Vrabel Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/core.c b/drivers/base/core.c index e73c92d13a23..d230ff4b3eec 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1142,6 +1142,9 @@ int device_for_each_child(struct device *parent, void *data, struct device *child; int error = 0; + if (!parent->p) + return 0; + klist_iter_init(&parent->p->klist_children, &i); while ((child = next_device(&i)) && !error) error = fn(child, data); -- cgit v1.2.3 From 8a577ffc75d9194fe8cdb7479236f2081c26ca1f Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Sat, 18 Apr 2009 15:05:45 -0700 Subject: driver: dont update dev_name via device_add path notice one system /proc/iomem some entries missed the name for pci_devices it turns that dev->dev.kobj name is changed after device_add. for pci code: via acpi_pci_root_driver.ops.add (aka acpi_pci_root_add) ==> pci_acpi_scan_root is used to scan pci bus/device, and at the same time we read the resource for pci_dev in the pci_read_bases, we have res->name = pci_name(pci_dev); pci_name is calling dev_name. later via acpi_pci_root_driver.ops.start (aka acpi_pci_root_start) ==> pci_bus_add_device to add all pci_dev in kobj tree. pci_bus_add_device will call device_add. actually in device_add /* first, register with generic layer. */ error = kobject_add(&dev->kobj, dev->kobj.parent, "%s", dev_name(dev)); if (error) goto Error; will get one new name for that kobj, old name is freed. [Impact: fix corrupted names in /proc/iomem ] Signed-off-by: Yinghai Lu Signed-off-by: Linus Torvalds --- drivers/base/core.c | 3 ++- lib/kobject.c | 3 +++ 2 files changed, 5 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/core.c b/drivers/base/core.c index d230ff4b3eec..4aa527b8a913 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -891,7 +891,8 @@ int device_add(struct device *dev) set_dev_node(dev, dev_to_node(parent)); /* first, register with generic layer. */ - error = kobject_add(&dev->kobj, dev->kobj.parent, "%s", dev_name(dev)); + /* we require the name to be set before, and pass NULL */ + error = kobject_add(&dev->kobj, dev->kobj.parent, NULL); if (error) goto Error; diff --git a/lib/kobject.c b/lib/kobject.c index a6dec32f2ddd..bacf6fe4f7a0 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -218,6 +218,9 @@ int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, const char *old_name = kobj->name; char *s; + if (kobj->name && !fmt) + return 0; + kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs); if (!kobj->name) return -ENOMEM; -- cgit v1.2.3 From d4d5291c8cd499b1b590336059d5cc3e24c1ced6 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Tue, 21 Apr 2009 13:32:54 -0700 Subject: driver synchronization: make scsi_wait_scan more advanced There is currently only one way for userspace to say "wait for my storage device to get ready for the modules I just loaded": to load the scsi_wait_scan module. Expectations of userspace are that once this module is loaded, all the (storage) devices for which the drivers were loaded before the module load are present. Now, there are some issues with the implementation, and the async stuff got caught in the middle of this: The existing code only waits for the scsy async probing to finish, but it did not take into account at all that probing might not have begun yet. (Russell ran into this problem on his computer and the fix works for him) This patch fixes this more thoroughly than the previous "fix", which had some bad side effects (namely, for kernel code that wanted to wait for the scsi scan it would also do an async sync, which would deadlock if you did it from async context already.. there's a report about that on lkml): The patch makes the module first wait for all device driver probes, and then it will wait for the scsi parallel scan to finish. Signed-off-by: Arjan van de Ven Tested-by: Russell King Signed-off-by: Linus Torvalds --- drivers/base/dd.c | 1 + drivers/scsi/scsi_scan.c | 2 -- drivers/scsi/scsi_wait_scan.c | 11 +++++++++++ include/linux/device.h | 1 + 4 files changed, 13 insertions(+), 2 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index f17c3266a0e0..742cbe6b042b 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -179,6 +179,7 @@ void wait_for_device_probe(void) wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); async_synchronize_full(); } +EXPORT_SYMBOL_GPL(wait_for_device_probe); /** * driver_probe_device - attempt to bind device & driver together diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index a14d245a66b8..6f51ca485f35 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -180,8 +180,6 @@ int scsi_complete_async_scans(void) spin_unlock(&async_scan_lock); kfree(data); - /* Synchronize async operations globally */ - async_synchronize_full(); return 0; } diff --git a/drivers/scsi/scsi_wait_scan.c b/drivers/scsi/scsi_wait_scan.c index 2f21af21269a..74708fcaf82f 100644 --- a/drivers/scsi/scsi_wait_scan.c +++ b/drivers/scsi/scsi_wait_scan.c @@ -11,10 +11,21 @@ */ #include +#include #include static int __init wait_scan_init(void) { + /* + * First we need to wait for device probing to finish; + * the drivers we just loaded might just still be probing + * and might not yet have reached the scsi async scanning + */ + wait_for_device_probe(); + /* + * and then we wait for the actual asynchronous scsi scan + * to finish. + */ scsi_complete_async_scans(); return 0; } diff --git a/include/linux/device.h b/include/linux/device.h index 2918c0e8fdfd..6a69caaac18a 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -551,6 +551,7 @@ extern int (*platform_notify_remove)(struct device *dev); extern struct device *get_device(struct device *dev); extern void put_device(struct device *dev); +extern void wait_for_device_probe(void); /* drivers/base/power/shutdown.c */ extern void device_shutdown(void); -- cgit v1.2.3