/* * Device driver for the Apple Desktop Bus * and the /dev/adb device on macintoshes. * * Copyright (C) 1996 Paul Mackerras. * * Modified to declare controllers as structures, added * client notification of bus reset and handles PowerBook * sleep, by Benjamin Herrenschmidt. * * To do: * * - /sys/bus/adb to list the devices and infos * - more /dev/adb to allow userland to receive the * flow of auto-polling datas from a given device. * - move bus probe to a kernel thread */ #include <linux/types.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/fs.h> #include <linux/mm.h> #include <linux/sched.h> #include <linux/adb.h> #include <linux/cuda.h> #include <linux/pmu.h> #include <linux/notifier.h> #include <linux/wait.h> #include <linux/init.h> #include <linux/delay.h> #include <linux/spinlock.h> #include <linux/completion.h> #include <linux/device.h> #include <linux/kthread.h> #include <linux/platform_device.h> #include <linux/mutex.h> #include <asm/uaccess.h> #ifdef CONFIG_PPC #include <asm/prom.h> #include <asm/machdep.h> #endif EXPORT_SYMBOL(adb_client_list); extern struct adb_driver via_macii_driver; extern struct adb_driver via_maciisi_driver; extern struct adb_driver via_cuda_driver; extern struct adb_driver adb_iop_driver; extern struct adb_driver via_pmu_driver; extern struct adb_driver macio_adb_driver; static DEFINE_MUTEX(adb_mutex); static struct adb_driver *adb_driver_list[] = { #ifdef CONFIG_ADB_MACII &via_macii_driver, #endif #ifdef CONFIG_ADB_MACIISI &via_maciisi_driver, #endif #ifdef CONFIG_ADB_CUDA &via_cuda_driver, #endif #ifdef CONFIG_ADB_IOP &adb_iop_driver, #endif #if defined(CONFIG_ADB_PMU) || defined(CONFIG_ADB_PMU68K) &via_pmu_driver, #endif #ifdef CONFIG_ADB_MACIO &macio_adb_driver, #endif NULL }; static struct class *adb_dev_class; static struct adb_driver *adb_controller; BLOCKING_NOTIFIER_HEAD(adb_client_list); static int adb_got_sleep; static int adb_inited; static DEFINE_SEMAPHORE(adb_probe_mutex); static int sleepy_trackpad; static int autopoll_devs; int __adb_probe_sync; static int adb_scan_bus(void); static int do_adb_reset_bus(void); static void adbdev_init(void); static int try_handler_change(int, int); static struct adb_handler { void (*handler)(unsigned char *, int, int); int original_address; int handler_id; int busy; } adb_handler[16]; /* * The adb_handler_mutex mutex protects all accesses to the original_address * and handler_id fields of adb_handler[i] for all i, and changes to the * handler field. * Accesses to the handler field are protected by the adb_handler_lock * rwlock. It is held across all calls to any handler, so that by the * time adb_unregister returns, we know that the old handler isn't being * called. */ static DEFINE_MUTEX(adb_handler_mutex); static DEFINE_RWLOCK(adb_handler_lock); #if 0 static void printADBreply(struct adb_request *req) { int i; printk("adb reply (%d)", req->reply_len); for(i = 0; i < req->reply_len; i++) printk(" %x", req->reply[i]); printk("\n"); } #endif static int adb_scan_bus(void) { int i, highFree=0, noMovement; int devmask = 0; struct adb_request req; /* assumes adb_handler[] is all zeroes at this point */ for (i = 1; i < 16; i++) { /* see if there is anything at address i */ adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, (i << 4) | 0xf); if (req.reply_len > 1) /* one or more devices at this address */ adb_handler[i].original_address = i; else if (i > highFree) highFree = i; } /* Note we reset noMovement to 0 each time we move a device */ for (noMovement = 1; noMovement < 2 && highFree > 0; noMovement++) { for (i = 1; i < 16; i++) { if (adb_handler[i].original_address == 0) continue; /* * Send a "talk register 3" command to address i * to provoke a collision if there is more than * one device at this address. */ adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, (i << 4) | 0xf); /* * Move the device(s) which didn't detect a * collision to address `highFree'. Hopefully * this only moves one device. */ adb_request(&req, NULL, ADBREQ_SYNC, 3, (i<< 4) | 0xb, (highFree | 0x60), 0xfe); /* * See if anybody actually moved. This is suggested * by HW TechNote 01: * * http://developer.apple.com/technotes/hw/hw_01.html */ adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, (highFree << 4) | 0xf); if (req.reply_len <= 1) continue; /* * Test whether there are any device(s) left * at address i. */ adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, (i << 4) | 0xf); if (req.reply_len > 1) { /* * There are still one or more devices * left at address i. Register the one(s) * we moved to `highFree', and find a new * value for highFree. */ adb_handler[highFree].original_address = adb_handler[i].original_address; while (highFree > 0 && adb_handler[highFree].original_address) highFree--; if (highFree <= 0) break; noMovement = 0; } else { /* * No devices left at address i; move the * one(s) we moved to `highFree' back to i. */ adb_request(&req, NULL, ADBREQ_SYNC, 3, (highFree << 4) | 0xb, (i | 0x60), 0xfe); } } } /* Now fill in the handler_id field of the adb_handler entries. */ printk(KERN_DEBUG "adb devices:"); for (i = 1; i < 16; i++) { if (adb_handler[i].original_address == 0) continue; adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, (i << 4) | 0xf); adb_handler[i].handler_id = req.reply[2]; printk(" [%d]: %d %x", i, adb_handler[i].original_address, adb_handler[i].handler_id); devmask |= 1 << i; } printk("\n"); return devmask; } /* * This kernel task handles ADB probing. It dies once probing is * completed. */ static int adb_probe_task(void *x) { printk(KERN_INFO "adb: starting probe task...\n"); do_adb_reset_bus(); printk(KERN_INFO "adb: finished probe task...\n"); up(&adb_probe_mutex); return 0; } static void __adb_probe_task(struct work_struct *bullshit) { kthread_run(adb_probe_task, NULL, "kadbprobe"); } static DECLARE_WORK(adb_reset_work, __adb_probe_task); int adb_reset_bus(void) { if (__adb_probe_sync) { do_adb_reset_bus(); return 0; } down(&adb_probe_mutex); schedule_work(&adb_reset_work); return 0; } #ifdef CONFIG_PM /* * notify clients before sleep */ static int adb_suspend(struct platform_device *dev, pm_message_t state) { adb_got_sleep = 1; /* We need to get a lock on the probe thread */ down(&adb_probe_mutex); /* Stop autopoll */ if (adb_controller->autopoll) adb_controller->autopoll(0); blocking_notifier_call_chain(&adb_client_list, ADB_MSG_POWERDOWN, NULL); return 0; } /* * reset bus after sleep */ static int adb_resume(struct platform_device *dev) { adb_got_sleep = 0; up(&adb_probe_mutex); adb_reset_bus(); return 0; } #endif /* CONFIG_PM */ static int __init adb_init(void) { struct adb_driver *driver; int i; #ifdef CONFIG_PPC32 if (!machine_is(chrp) && !machine_is(powermac)) return 0; #endif #ifdef CONFIG_MAC if (!MACH_IS_MAC) return 0; #endif /* xmon may do early-init */ if (adb_inited) return 0; adb_inited = 1; adb_controller = NULL; i = 0; while ((driver = adb_driver_list[i++]) != NULL) { if (!driver->probe()) { adb_controller = driver; break; } } if (adb_controller != NULL && adb_controller->init && adb_controller->init()) adb_controller = NULL; if (adb_controller == NULL) { printk(KERN_WARNING "Warning: no ADB interface detected\n"); } else { #ifdef CONFIG_PPC if (of_machine_is_compatible("AAPL,PowerBook1998") || of_machine_is_compatible("PowerBook1,1")) sleepy_trackpad = 1; #endif /* CONFIG_PPC */ adbdev_init(); adb_reset_bus(); } return 0; } device_initcall(adb_init); static int do_adb_reset_bus(void) { int ret; if (adb_controller == NULL) return -ENXIO; if (adb_controller->autopoll) adb_controller->autopoll(0); blocking_notifier_call_chain(&adb_client_list, ADB_MSG_PRE_RESET, NULL); if (sleepy_trackpad) { /* Let the trackpad settle down */ msleep(500); } mutex_lock(&adb_handler_mutex); write_lock_irq(&adb_handler_lock); memset(adb_handler, 0, sizeof(adb_handler)); write_unlock_irq(&adb_handler_lock); /* That one is still a bit synchronous, oh well... */ if (adb_controller->reset_bus) ret = adb_controller->reset_bus(); else ret = 0; if (sleepy_trackpad) { /* Let the trackpad settle down */ msleep(1500); } if (!ret) { autopoll_devs = adb_scan_bus(); if (adb_controller->autopoll) adb_controller->autopoll(autopoll_devs); } mutex_unlock(&adb_handler_mutex); blocking_notifier_call_chain(&adb_client_list, ADB_MSG_POST_RESET, NULL); return ret; } void adb_poll(void) { if ((adb_controller == NULL)||(adb_controller->poll == NULL)) return; adb_controller->poll(); } static void adb_sync_req_done(struct adb_request *req) { struct completion *comp = req->arg; complete(comp); } int adb_request(struct adb_request *req, void (*done)(struct adb_request *), int flags, int nbytes, ...) { va_list list; int i; int rc; struct completion comp; if ((adb_controller == NULL) || (adb_controller->send_request == NULL)) return -ENXIO; if (nbytes < 1) return -EINVAL; req->nbytes = nbytes+1; req->done = done; req->reply_expected = flags & ADBREQ_REPLY; req->data[0] = ADB_PACKET; va_start(list, nbytes); for (i = 0; i < nbytes; ++i) req->data[i+1] = va_arg(list, int); va_end(list); if (flags & ADBREQ_NOSEND) return 0; /* Synchronous requests block using an on-stack completion */ if (flags & ADBREQ_SYNC) { WARN_ON(done); req->done = adb_sync_req_done; req->arg = ∁ init_completion(&comp); } rc = adb_controller->send_request(req, 0); if ((flags & ADBREQ_SYNC) && !rc && !req->complete) wait_for_completion(&comp); return rc; } /* Ultimately this should return the number of devices with the given default id. And it does it now ! Note: changed behaviour: This function will now register if default_id _and_ handler_id both match but handler_id can be left to 0 to match with default_id only. When handler_id is set, this function will try to adjust the handler_id id it doesn't match. */ int adb_register(int default_id, int handler_id, struct adb_ids *ids, void (*handler)(unsigned char *, int, int)) { int i; mutex_lock(&adb_handler_mutex); ids->nids = 0; for (i = 1; i < 16; i++) { if ((adb_handler[i].original_address == default_id) && (!handler_id || (handler_id == adb_handler[i].handler_id) || try_handler_change(i, handler_id))) { if (adb_handler[i].handler != 0) { printk(KERN_ERR "Two handlers for ADB device %d\n", default_id); continue; } write_lock_irq(&adb_handler_lock); adb_handler[i].handler = handler; write_unlock_irq(&adb_handler_lock); ids->id[ids->nids++] = i; } } mutex_unlock(&adb_handler_mutex); return ids->nids; } int adb_unregister(int index) { int ret = -ENODEV; mutex_lock(&adb_handler_mutex); write_lock_irq(&adb_handler_lock); if (adb_handler[index].handler) { while(adb_handler[index].busy) { write_unlock_irq(&adb_handler_lock); yield(); write_lock_irq(&adb_handler_lock); } ret = 0; adb_handler[index].handler = NULL; } write_unlock_irq(&adb_handler_lock); mutex_unlock(&adb_handler_mutex); return ret; } void adb_input(unsigned char *buf, int nb, int autopoll) { int i, id; static int dump_adb_input = 0; unsigned long flags; void (*handler)(unsigned char *, int, int); /* We skip keystrokes and mouse moves when the sleep process * has been started. We stop autopoll, but this is another security */ if (adb_got_sleep) return; id = buf[0] >> 4; if (dump_adb_input) { printk(KERN_INFO "adb packet: "); for (i = 0; i < nb; ++i) printk(" %x", buf[i]); printk(", id = %d\n", id); } write_lock_irqsave(&adb_handler_lock, flags); handler = adb_handler[id].handler; if (handler != NULL) adb_handler[id].busy = 1; write_unlock_irqrestore(&adb_handler_lock, flags); if (handler != NULL) { (*handler)(buf, nb, autopoll); wmb(); adb_handler[id].busy = 0; } } /* Try to change handler to new_id. Will return 1 if successful. */ static int try_handler_change(int address, int new_id) { struct adb_request req; if (adb_handler[address].handler_id == new_id) return 1; adb_request(&req, NULL, ADBREQ_SYNC, 3, ADB_WRITEREG(address, 3), address | 0x20, new_id); adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1, ADB_READREG(address, 3)); if (req.reply_len < 2) return 0; if (req.reply[2] != new_id) return 0; adb_handler[address].handler_id = req.reply[2]; return 1; } int adb_try_handler_change(int address, int new_id) { int ret; mutex_lock(&adb_handler_mutex); ret = try_handler_change(address, new_id); mutex_unlock(&adb_handler_mutex); return ret; } int adb_get_infos(int address, int *original_address, int *handler_id) { mutex_lock(&adb_handler_mutex); *original_address = adb_handler[address].original_address; *handler_id = adb_handler[address].handler_id; mutex_unlock(&adb_handler_mutex); return (*original_address != 0); } /* * /dev/adb device driver. */ #define ADB_MAJOR 56 /* major number for /dev/adb */ struct adbdev_state { spinlock_t lock; atomic_t n_pending; struct adb_request *completed; wait_queue_head_t wait_queue; int inuse; }; static void adb_write_done(struct adb_request *req) { struct adbdev_state *state = (struct adbdev_state *) req->arg; unsigned long flags; if (!req->complete) { req->reply_len = 0; req->complete = 1; } spin_lock_irqsave(&state->lock, flags); atomic_dec(&state->n_pending); if (!state->inuse) { kfree(req); if (atomic_read(&state->n_pending) == 0) { spin_unlock_irqrestore(&state->lock, flags); kfree(state); return; } } else { struct adb_request **ap = &state->completed; while (*ap != NULL) ap = &(*ap)->next; req->next = NULL; *ap = req; wake_up_interruptible(&state->wait_queue); } spin_unlock_irqrestore(&state->lock, flags); } static int do_adb_query(struct adb_request *req) { int ret = -EINVAL; switch(req->data[1]) { case ADB_QUERY_GETDEVINFO: if (req->nbytes < 3) break; mutex_lock(&adb_handler_mutex); req->reply[0] = adb_handler[req->data[2]].original_address; req->reply[1] = adb_handler[req->data[2]].handler_id; mutex_unlock(&adb_handler_mutex); req->complete = 1; req->reply_len = 2; adb_write_done(req); ret = 0; break; } return ret; } static int adb_open(struct inode *inode, struct file *file) { struct adbdev_state *state; int ret = 0; mutex_lock(&adb_mutex); if (iminor(inode) > 0 || adb_controller == NULL) { ret = -ENXIO; goto out; } state = kmalloc(sizeof(struct adbdev_state), GFP_KERNEL); if (state == 0) { ret = -ENOMEM; goto out; } file->private_data = state; spin_lock_init(&state->lock); atomic_set(&state->n_pending, 0); state->completed = NULL; init_waitqueue_head(&state->wait_queue); state->inuse = 1; out: mutex_unlock(&adb_mutex); return ret; } static int adb_release(struct inode *inode, struct file *file) { struct adbdev_state *state = file->private_data; unsigned long flags; mutex_lock(&adb_mutex); if (state) { file->private_data = NULL; spin_lock_irqsave(&state->lock, flags); if (atomic_read(&state->n_pending) == 0 && state->completed == NULL) { spin_unlock_irqrestore(&state->lock, flags); kfree(state); } else { state->inuse = 0; spin_unlock_irqrestore(&state->lock, flags); } } mutex_unlock(&adb_mutex); return 0; } static ssize_t adb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { int ret = 0; struct adbdev_state *state = file->private_data; struct adb_request *req; wait_queue_t wait = __WAITQUEUE_INITIALIZER(wait,current); unsigned long flags; if (count < 2) return -EINVAL; if (count > sizeof(req->reply)) count = sizeof(req->reply); if (!access_ok(VERIFY_WRITE, buf, count)) return -EFAULT; req = NULL; spin_lock_irqsave(&state->lock, flags); add_wait_queue(&state->wait_queue, &wait); set_current_state(TASK_INTERRUPTIBLE); for (;;) { req = state->completed; if (req != NULL) state->completed = req->next; else if (atomic_read(&state->n_pending) == 0) ret = -EIO; if (req != NULL || ret != 0) break; if (file->f_flags & O_NONBLOCK) { ret = -EAGAIN; break; } if (signal_pending(current)) { ret = -ERESTARTSYS; break; } spin_unlock_irqrestore(&state->lock, flags); schedule(); spin_lock_irqsave(&state->lock, flags); } set_current_state(TASK_RUNNING); remove_wait_queue(&state->wait_queue, &wait); spin_unlock_irqrestore(&state->lock, flags); if (ret) return ret; ret = req->reply_len; if (ret > count) ret = count; if (ret > 0 && copy_to_user(buf, req->reply, ret)) ret = -EFAULT; kfree(req); return ret; } static ssize_t adb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { int ret/*, i*/; struct adbdev_state *state = file->private_data; struct adb_request *req; if (count < 2 || count > sizeof(req->data)) return -EINVAL; if (adb_controller == NULL) return -ENXIO; if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; req = kmalloc(sizeof(struct adb_request), GFP_KERNEL); if (req == NULL) return -ENOMEM; req->nbytes = count; req->done = adb_write_done; req->arg = (void *) state; req->complete = 0; ret = -EFAULT; if (copy_from_user(req->data, buf, count)) goto out; atomic_inc(&state->n_pending); /* If a probe is in progress or we are sleeping, wait for it to complete */ down(&adb_probe_mutex); /* Queries are special requests sent to the ADB driver itself */ if (req->data[0] == ADB_QUERY) { if (count > 1) ret = do_adb_query(req); else ret = -EINVAL; up(&adb_probe_mutex); } /* Special case for ADB_BUSRESET request, all others are sent to the controller */ else if ((req->data[0] == ADB_PACKET)&&(count > 1) &&(req->data[1] == ADB_BUSRESET)) { ret = do_adb_reset_bus(); up(&adb_probe_mutex); atomic_dec(&state->n_pending); if (ret == 0) ret = count; goto out; } else { req->reply_expected = ((req->data[1] & 0xc) == 0xc); if (adb_controller && adb_controller->send_request) ret = adb_controller->send_request(req, 0); else ret = -ENXIO; up(&adb_probe_mutex); } if (ret != 0) { atomic_dec(&state->n_pending); goto out; } return count; out: kfree(req); return ret; } static const struct file_operations adb_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .read = adb_read, .write = adb_write, .open = adb_open, .release = adb_release, }; static struct platform_driver adb_pfdrv = { .driver = { .name = "adb", }, #ifdef CONFIG_PM .suspend = adb_suspend, .resume = adb_resume, #endif }; static struct platform_device adb_pfdev = { .name = "adb", }; static int __init adb_dummy_probe(struct platform_device *dev) { if (dev == &adb_pfdev) return 0; return -ENODEV; } static void __init adbdev_init(void) { if (register_chrdev(ADB_MAJOR, "adb", &adb_fops)) { printk(KERN_ERR "adb: unable to get major %d\n", ADB_MAJOR); return; } adb_dev_class = class_create(THIS_MODULE, "adb"); if (IS_ERR(adb_dev_class)) return; device_create(adb_dev_class, NULL, MKDEV(ADB_MAJOR, 0), NULL, "adb"); platform_device_register(&adb_pfdev); platform_driver_probe(&adb_pfdrv, adb_dummy_probe); }