diff options
Diffstat (limited to 'drivers/base/dd.c')
| -rw-r--r-- | drivers/base/dd.c | 147 |
1 files changed, 110 insertions, 37 deletions
diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 889c71111239..b5f43c3e44fa 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c | |||
| @@ -17,6 +17,7 @@ | |||
| 17 | 17 | ||
| 18 | #include <linux/device.h> | 18 | #include <linux/device.h> |
| 19 | #include <linux/module.h> | 19 | #include <linux/module.h> |
| 20 | #include <linux/kthread.h> | ||
| 20 | 21 | ||
| 21 | #include "base.h" | 22 | #include "base.h" |
| 22 | #include "power/power.h" | 23 | #include "power/power.h" |
| @@ -38,66 +39,73 @@ | |||
| 38 | * | 39 | * |
| 39 | * This function must be called with @dev->sem held. | 40 | * This function must be called with @dev->sem held. |
| 40 | */ | 41 | */ |
| 41 | void device_bind_driver(struct device * dev) | 42 | int device_bind_driver(struct device *dev) |
| 42 | { | 43 | { |
| 43 | if (klist_node_attached(&dev->knode_driver)) | 44 | int ret; |
| 44 | return; | 45 | |
| 46 | if (klist_node_attached(&dev->knode_driver)) { | ||
| 47 | printk(KERN_WARNING "%s: device %s already bound\n", | ||
| 48 | __FUNCTION__, kobject_name(&dev->kobj)); | ||
| 49 | return 0; | ||
| 50 | } | ||
| 45 | 51 | ||
| 46 | pr_debug("bound device '%s' to driver '%s'\n", | 52 | pr_debug("bound device '%s' to driver '%s'\n", |
| 47 | dev->bus_id, dev->driver->name); | 53 | dev->bus_id, dev->driver->name); |
| 48 | klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices); | 54 | klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices); |
| 49 | sysfs_create_link(&dev->driver->kobj, &dev->kobj, | 55 | ret = sysfs_create_link(&dev->driver->kobj, &dev->kobj, |
| 50 | kobject_name(&dev->kobj)); | 56 | kobject_name(&dev->kobj)); |
| 51 | sysfs_create_link(&dev->kobj, &dev->driver->kobj, "driver"); | 57 | if (ret == 0) { |
| 58 | ret = sysfs_create_link(&dev->kobj, &dev->driver->kobj, | ||
| 59 | "driver"); | ||
| 60 | if (ret) | ||
| 61 | sysfs_remove_link(&dev->driver->kobj, | ||
| 62 | kobject_name(&dev->kobj)); | ||
| 63 | } | ||
| 64 | return ret; | ||
| 52 | } | 65 | } |
| 53 | 66 | ||
| 54 | /** | 67 | struct stupid_thread_structure { |
| 55 | * driver_probe_device - attempt to bind device & driver. | 68 | struct device_driver *drv; |
| 56 | * @drv: driver. | 69 | struct device *dev; |
| 57 | * @dev: device. | 70 | }; |
| 58 | * | 71 | |
| 59 | * First, we call the bus's match function, if one present, which | 72 | static atomic_t probe_count = ATOMIC_INIT(0); |
| 60 | * should compare the device IDs the driver supports with the | 73 | static int really_probe(void *void_data) |
| 61 | * device IDs of the device. Note we don't do this ourselves | ||
| 62 | * because we don't know the format of the ID structures, nor what | ||
| 63 | * is to be considered a match and what is not. | ||
| 64 | * | ||
| 65 | * This function returns 1 if a match is found, an error if one | ||
| 66 | * occurs (that is not -ENODEV or -ENXIO), and 0 otherwise. | ||
| 67 | * | ||
| 68 | * This function must be called with @dev->sem held. When called | ||
| 69 | * for a USB interface, @dev->parent->sem must be held as well. | ||
| 70 | */ | ||
| 71 | int driver_probe_device(struct device_driver * drv, struct device * dev) | ||
| 72 | { | 74 | { |
| 75 | struct stupid_thread_structure *data = void_data; | ||
| 76 | struct device_driver *drv = data->drv; | ||
| 77 | struct device *dev = data->dev; | ||
| 73 | int ret = 0; | 78 | int ret = 0; |
| 74 | 79 | ||
| 75 | if (drv->bus->match && !drv->bus->match(dev, drv)) | 80 | atomic_inc(&probe_count); |
| 76 | goto Done; | 81 | pr_debug("%s: Probing driver %s with device %s\n", |
| 82 | drv->bus->name, drv->name, dev->bus_id); | ||
| 77 | 83 | ||
| 78 | pr_debug("%s: Matched Device %s with Driver %s\n", | ||
| 79 | drv->bus->name, dev->bus_id, drv->name); | ||
| 80 | dev->driver = drv; | 84 | dev->driver = drv; |
| 81 | if (dev->bus->probe) { | 85 | if (dev->bus->probe) { |
| 82 | ret = dev->bus->probe(dev); | 86 | ret = dev->bus->probe(dev); |
| 83 | if (ret) { | 87 | if (ret) { |
| 84 | dev->driver = NULL; | 88 | dev->driver = NULL; |
| 85 | goto ProbeFailed; | 89 | goto probe_failed; |
| 86 | } | 90 | } |
| 87 | } else if (drv->probe) { | 91 | } else if (drv->probe) { |
| 88 | ret = drv->probe(dev); | 92 | ret = drv->probe(dev); |
| 89 | if (ret) { | 93 | if (ret) { |
| 90 | dev->driver = NULL; | 94 | dev->driver = NULL; |
| 91 | goto ProbeFailed; | 95 | goto probe_failed; |
| 92 | } | 96 | } |
| 93 | } | 97 | } |
| 94 | device_bind_driver(dev); | 98 | if (device_bind_driver(dev)) { |
| 99 | printk(KERN_ERR "%s: device_bind_driver(%s) failed\n", | ||
| 100 | __FUNCTION__, dev->bus_id); | ||
| 101 | /* How does undo a ->probe? We're screwed. */ | ||
| 102 | } | ||
| 95 | ret = 1; | 103 | ret = 1; |
| 96 | pr_debug("%s: Bound Device %s to Driver %s\n", | 104 | pr_debug("%s: Bound Device %s to Driver %s\n", |
| 97 | drv->bus->name, dev->bus_id, drv->name); | 105 | drv->bus->name, dev->bus_id, drv->name); |
| 98 | goto Done; | 106 | goto done; |
| 99 | 107 | ||
| 100 | ProbeFailed: | 108 | probe_failed: |
| 101 | if (ret == -ENODEV || ret == -ENXIO) { | 109 | if (ret == -ENODEV || ret == -ENXIO) { |
| 102 | /* Driver matched, but didn't support device | 110 | /* Driver matched, but didn't support device |
| 103 | * or device not found. | 111 | * or device not found. |
| @@ -110,7 +118,71 @@ int driver_probe_device(struct device_driver * drv, struct device * dev) | |||
| 110 | "%s: probe of %s failed with error %d\n", | 118 | "%s: probe of %s failed with error %d\n", |
| 111 | drv->name, dev->bus_id, ret); | 119 | drv->name, dev->bus_id, ret); |
| 112 | } | 120 | } |
| 113 | Done: | 121 | done: |
| 122 | kfree(data); | ||
| 123 | atomic_dec(&probe_count); | ||
| 124 | return ret; | ||
| 125 | } | ||
| 126 | |||
| 127 | /** | ||
| 128 | * driver_probe_done | ||
| 129 | * Determine if the probe sequence is finished or not. | ||
| 130 | * | ||
| 131 | * Should somehow figure out how to use a semaphore, not an atomic variable... | ||
| 132 | */ | ||
| 133 | int driver_probe_done(void) | ||
| 134 | { | ||
| 135 | pr_debug("%s: probe_count = %d\n", __FUNCTION__, | ||
| 136 | atomic_read(&probe_count)); | ||
| 137 | if (atomic_read(&probe_count)) | ||
| 138 | return -EBUSY; | ||
| 139 | return 0; | ||
| 140 | } | ||
| 141 | |||
| 142 | /** | ||
| 143 | * driver_probe_device - attempt to bind device & driver together | ||
| 144 | * @drv: driver to bind a device to | ||
| 145 | * @dev: device to try to bind to the driver | ||
| 146 | * | ||
| 147 | * First, we call the bus's match function, if one present, which should | ||
| 148 | * compare the device IDs the driver supports with the device IDs of the | ||
| 149 | * device. Note we don't do this ourselves because we don't know the | ||
| 150 | * format of the ID structures, nor what is to be considered a match and | ||
| 151 | * what is not. | ||
| 152 | * | ||
| 153 | * This function returns 1 if a match is found, an error if one occurs | ||
| 154 | * (that is not -ENODEV or -ENXIO), and 0 otherwise. | ||
| 155 | * | ||
| 156 | * This function must be called with @dev->sem held. When called for a | ||
| 157 | * USB interface, @dev->parent->sem must be held as well. | ||
| 158 | */ | ||
| 159 | int driver_probe_device(struct device_driver * drv, struct device * dev) | ||
| 160 | { | ||
| 161 | struct stupid_thread_structure *data; | ||
| 162 | struct task_struct *probe_task; | ||
| 163 | int ret = 0; | ||
| 164 | |||
| 165 | if (!device_is_registered(dev)) | ||
| 166 | return -ENODEV; | ||
| 167 | if (drv->bus->match && !drv->bus->match(dev, drv)) | ||
| 168 | goto done; | ||
| 169 | |||
| 170 | pr_debug("%s: Matched Device %s with Driver %s\n", | ||
| 171 | drv->bus->name, dev->bus_id, drv->name); | ||
| 172 | |||
| 173 | data = kmalloc(sizeof(*data), GFP_KERNEL); | ||
| 174 | data->drv = drv; | ||
| 175 | data->dev = dev; | ||
| 176 | |||
| 177 | if (drv->multithread_probe) { | ||
| 178 | probe_task = kthread_run(really_probe, data, | ||
| 179 | "probe-%s", dev->bus_id); | ||
| 180 | if (IS_ERR(probe_task)) | ||
| 181 | ret = PTR_ERR(probe_task); | ||
| 182 | } else | ||
| 183 | ret = really_probe(data); | ||
| 184 | |||
| 185 | done: | ||
| 114 | return ret; | 186 | return ret; |
| 115 | } | 187 | } |
| 116 | 188 | ||
| @@ -139,8 +211,9 @@ int device_attach(struct device * dev) | |||
| 139 | 211 | ||
| 140 | down(&dev->sem); | 212 | down(&dev->sem); |
| 141 | if (dev->driver) { | 213 | if (dev->driver) { |
| 142 | device_bind_driver(dev); | 214 | ret = device_bind_driver(dev); |
| 143 | ret = 1; | 215 | if (ret == 0) |
| 216 | ret = 1; | ||
| 144 | } else | 217 | } else |
| 145 | ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); | 218 | ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); |
| 146 | up(&dev->sem); | 219 | up(&dev->sem); |
| @@ -182,9 +255,9 @@ static int __driver_attach(struct device * dev, void * data) | |||
| 182 | * returns 0 and the @dev->driver is set, we've found a | 255 | * returns 0 and the @dev->driver is set, we've found a |
| 183 | * compatible pair. | 256 | * compatible pair. |
| 184 | */ | 257 | */ |
| 185 | void driver_attach(struct device_driver * drv) | 258 | int driver_attach(struct device_driver * drv) |
| 186 | { | 259 | { |
| 187 | bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); | 260 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
| 188 | } | 261 | } |
| 189 | 262 | ||
| 190 | /** | 263 | /** |
