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![Finn Thain](/assets/img/avatar_default.png)
Avoid the KERN_CONT problem by avoiding message fragments. The problem arises during async ADB bus probing, when ADB messages may get mixed up with other messages. See also, commit4bcc595ccd
("printk: reinstate KERN_CONT for printing continuation lines"). Remove a number of printk() continuation lines by logging handler changes in adb_try_handler_change() instead. This patch addresses the problematic use of "\n" at the beginning of pr_cont() messages, which got overlooked in commitf2be629568
("macintosh/adb: Properly mark continued kernel messages"). That commit also changed printk(KERN_DEBUG ...) to pr_debug(...), which hinders work on low-level ADB driver bugs. Revert that change. Cc: Andreas Schwab <schwab@linux-m68k.org> Tested-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
898 lines
20 KiB
C
898 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Device driver for the Apple Desktop Bus
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* and the /dev/adb device on macintoshes.
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*
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* Copyright (C) 1996 Paul Mackerras.
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*
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* Modified to declare controllers as structures, added
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* client notification of bus reset and handles PowerBook
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* sleep, by Benjamin Herrenschmidt.
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*
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* To do:
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*
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* - /sys/bus/adb to list the devices and infos
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* - more /dev/adb to allow userland to receive the
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* flow of auto-polling datas from a given device.
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* - move bus probe to a kernel thread
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*/
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/sched/signal.h>
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#include <linux/adb.h>
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#include <linux/cuda.h>
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#include <linux/pmu.h>
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#include <linux/notifier.h>
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#include <linux/wait.h>
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#include <linux/init.h>
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#include <linux/delay.h>
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#include <linux/spinlock.h>
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#include <linux/completion.h>
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#include <linux/device.h>
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#include <linux/kthread.h>
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#include <linux/platform_device.h>
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#include <linux/mutex.h>
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#include <linux/uaccess.h>
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#ifdef CONFIG_PPC
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#include <asm/prom.h>
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#include <asm/machdep.h>
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#endif
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EXPORT_SYMBOL(adb_client_list);
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extern struct adb_driver via_macii_driver;
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extern struct adb_driver via_cuda_driver;
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extern struct adb_driver adb_iop_driver;
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extern struct adb_driver via_pmu_driver;
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extern struct adb_driver macio_adb_driver;
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static DEFINE_MUTEX(adb_mutex);
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static struct adb_driver *adb_driver_list[] = {
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#ifdef CONFIG_ADB_MACII
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&via_macii_driver,
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#endif
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#ifdef CONFIG_ADB_CUDA
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&via_cuda_driver,
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#endif
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#ifdef CONFIG_ADB_IOP
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&adb_iop_driver,
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#endif
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#ifdef CONFIG_ADB_PMU
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&via_pmu_driver,
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#endif
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#ifdef CONFIG_ADB_MACIO
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&macio_adb_driver,
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#endif
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NULL
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};
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static struct class *adb_dev_class;
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static struct adb_driver *adb_controller;
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BLOCKING_NOTIFIER_HEAD(adb_client_list);
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static int adb_got_sleep;
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static int adb_inited;
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static DEFINE_SEMAPHORE(adb_probe_mutex);
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static int sleepy_trackpad;
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static int autopoll_devs;
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int __adb_probe_sync;
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static int adb_scan_bus(void);
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static int do_adb_reset_bus(void);
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static void adbdev_init(void);
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static int try_handler_change(int, int);
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static struct adb_handler {
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void (*handler)(unsigned char *, int, int);
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int original_address;
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int handler_id;
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int busy;
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} adb_handler[16];
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/*
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* The adb_handler_mutex mutex protects all accesses to the original_address
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* and handler_id fields of adb_handler[i] for all i, and changes to the
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* handler field.
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* Accesses to the handler field are protected by the adb_handler_lock
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* rwlock. It is held across all calls to any handler, so that by the
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* time adb_unregister returns, we know that the old handler isn't being
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* called.
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*/
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static DEFINE_MUTEX(adb_handler_mutex);
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static DEFINE_RWLOCK(adb_handler_lock);
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#if 0
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static void printADBreply(struct adb_request *req)
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{
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int i;
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printk("adb reply (%d)", req->reply_len);
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for(i = 0; i < req->reply_len; i++)
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printk(" %x", req->reply[i]);
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printk("\n");
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}
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#endif
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static int adb_scan_bus(void)
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{
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int i, highFree=0, noMovement;
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int devmask = 0;
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struct adb_request req;
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/* assumes adb_handler[] is all zeroes at this point */
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for (i = 1; i < 16; i++) {
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/* see if there is anything at address i */
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adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
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(i << 4) | 0xf);
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if (req.reply_len > 1)
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/* one or more devices at this address */
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adb_handler[i].original_address = i;
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else if (i > highFree)
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highFree = i;
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}
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/* Note we reset noMovement to 0 each time we move a device */
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for (noMovement = 1; noMovement < 2 && highFree > 0; noMovement++) {
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for (i = 1; i < 16; i++) {
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if (adb_handler[i].original_address == 0)
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continue;
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/*
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* Send a "talk register 3" command to address i
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* to provoke a collision if there is more than
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* one device at this address.
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*/
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adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
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(i << 4) | 0xf);
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/*
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* Move the device(s) which didn't detect a
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* collision to address `highFree'. Hopefully
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* this only moves one device.
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*/
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adb_request(&req, NULL, ADBREQ_SYNC, 3,
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(i<< 4) | 0xb, (highFree | 0x60), 0xfe);
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/*
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* See if anybody actually moved. This is suggested
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* by HW TechNote 01:
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*
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* http://developer.apple.com/technotes/hw/hw_01.html
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*/
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adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
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(highFree << 4) | 0xf);
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if (req.reply_len <= 1) continue;
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/*
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* Test whether there are any device(s) left
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* at address i.
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*/
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adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
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(i << 4) | 0xf);
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if (req.reply_len > 1) {
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/*
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* There are still one or more devices
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* left at address i. Register the one(s)
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* we moved to `highFree', and find a new
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* value for highFree.
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*/
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adb_handler[highFree].original_address =
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adb_handler[i].original_address;
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while (highFree > 0 &&
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adb_handler[highFree].original_address)
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highFree--;
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if (highFree <= 0)
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break;
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noMovement = 0;
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} else {
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/*
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* No devices left at address i; move the
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* one(s) we moved to `highFree' back to i.
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*/
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adb_request(&req, NULL, ADBREQ_SYNC, 3,
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(highFree << 4) | 0xb,
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(i | 0x60), 0xfe);
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}
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}
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}
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/* Now fill in the handler_id field of the adb_handler entries. */
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for (i = 1; i < 16; i++) {
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if (adb_handler[i].original_address == 0)
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continue;
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adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
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(i << 4) | 0xf);
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adb_handler[i].handler_id = req.reply[2];
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printk(KERN_DEBUG "adb device [%d]: %d 0x%X\n", i,
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adb_handler[i].original_address,
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adb_handler[i].handler_id);
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devmask |= 1 << i;
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}
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return devmask;
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}
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/*
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* This kernel task handles ADB probing. It dies once probing is
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* completed.
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*/
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static int
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adb_probe_task(void *x)
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{
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pr_debug("adb: starting probe task...\n");
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do_adb_reset_bus();
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pr_debug("adb: finished probe task...\n");
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up(&adb_probe_mutex);
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return 0;
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}
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static void
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__adb_probe_task(struct work_struct *bullshit)
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{
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kthread_run(adb_probe_task, NULL, "kadbprobe");
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}
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static DECLARE_WORK(adb_reset_work, __adb_probe_task);
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int
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adb_reset_bus(void)
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{
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if (__adb_probe_sync) {
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do_adb_reset_bus();
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return 0;
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}
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down(&adb_probe_mutex);
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schedule_work(&adb_reset_work);
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return 0;
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}
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#ifdef CONFIG_PM
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/*
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* notify clients before sleep
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*/
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static int __adb_suspend(struct platform_device *dev, pm_message_t state)
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{
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adb_got_sleep = 1;
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/* We need to get a lock on the probe thread */
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down(&adb_probe_mutex);
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/* Stop autopoll */
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if (adb_controller->autopoll)
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adb_controller->autopoll(0);
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blocking_notifier_call_chain(&adb_client_list, ADB_MSG_POWERDOWN, NULL);
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return 0;
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}
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static int adb_suspend(struct device *dev)
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{
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return __adb_suspend(to_platform_device(dev), PMSG_SUSPEND);
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}
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static int adb_freeze(struct device *dev)
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{
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return __adb_suspend(to_platform_device(dev), PMSG_FREEZE);
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}
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static int adb_poweroff(struct device *dev)
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{
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return __adb_suspend(to_platform_device(dev), PMSG_HIBERNATE);
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}
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/*
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* reset bus after sleep
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*/
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static int __adb_resume(struct platform_device *dev)
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{
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adb_got_sleep = 0;
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up(&adb_probe_mutex);
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adb_reset_bus();
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return 0;
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}
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static int adb_resume(struct device *dev)
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{
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return __adb_resume(to_platform_device(dev));
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}
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#endif /* CONFIG_PM */
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static int __init adb_init(void)
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{
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struct adb_driver *driver;
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int i;
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#ifdef CONFIG_PPC32
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if (!machine_is(chrp) && !machine_is(powermac))
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return 0;
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#endif
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#ifdef CONFIG_MAC
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if (!MACH_IS_MAC)
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return 0;
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#endif
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/* xmon may do early-init */
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if (adb_inited)
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return 0;
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adb_inited = 1;
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adb_controller = NULL;
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i = 0;
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while ((driver = adb_driver_list[i++]) != NULL) {
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if (!driver->probe()) {
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adb_controller = driver;
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break;
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}
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}
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if (adb_controller != NULL && adb_controller->init &&
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adb_controller->init())
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adb_controller = NULL;
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if (adb_controller == NULL) {
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pr_warn("Warning: no ADB interface detected\n");
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} else {
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#ifdef CONFIG_PPC
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if (of_machine_is_compatible("AAPL,PowerBook1998") ||
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of_machine_is_compatible("PowerBook1,1"))
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sleepy_trackpad = 1;
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#endif /* CONFIG_PPC */
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adbdev_init();
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adb_reset_bus();
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}
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return 0;
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}
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device_initcall(adb_init);
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static int
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do_adb_reset_bus(void)
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{
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int ret;
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if (adb_controller == NULL)
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return -ENXIO;
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if (adb_controller->autopoll)
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adb_controller->autopoll(0);
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blocking_notifier_call_chain(&adb_client_list,
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ADB_MSG_PRE_RESET, NULL);
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if (sleepy_trackpad) {
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/* Let the trackpad settle down */
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msleep(500);
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}
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mutex_lock(&adb_handler_mutex);
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write_lock_irq(&adb_handler_lock);
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memset(adb_handler, 0, sizeof(adb_handler));
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write_unlock_irq(&adb_handler_lock);
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/* That one is still a bit synchronous, oh well... */
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if (adb_controller->reset_bus)
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ret = adb_controller->reset_bus();
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else
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ret = 0;
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if (sleepy_trackpad) {
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/* Let the trackpad settle down */
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msleep(1500);
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}
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if (!ret) {
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autopoll_devs = adb_scan_bus();
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if (adb_controller->autopoll)
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adb_controller->autopoll(autopoll_devs);
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}
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mutex_unlock(&adb_handler_mutex);
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blocking_notifier_call_chain(&adb_client_list,
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ADB_MSG_POST_RESET, NULL);
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return ret;
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}
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void
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adb_poll(void)
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{
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if ((adb_controller == NULL)||(adb_controller->poll == NULL))
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return;
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adb_controller->poll();
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}
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EXPORT_SYMBOL(adb_poll);
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static void adb_sync_req_done(struct adb_request *req)
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{
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struct completion *comp = req->arg;
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complete(comp);
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}
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int
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adb_request(struct adb_request *req, void (*done)(struct adb_request *),
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int flags, int nbytes, ...)
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{
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va_list list;
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int i;
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int rc;
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struct completion comp;
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if ((adb_controller == NULL) || (adb_controller->send_request == NULL))
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return -ENXIO;
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if (nbytes < 1)
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return -EINVAL;
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req->nbytes = nbytes+1;
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req->done = done;
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req->reply_expected = flags & ADBREQ_REPLY;
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req->data[0] = ADB_PACKET;
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va_start(list, nbytes);
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for (i = 0; i < nbytes; ++i)
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req->data[i+1] = va_arg(list, int);
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va_end(list);
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if (flags & ADBREQ_NOSEND)
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return 0;
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/* Synchronous requests block using an on-stack completion */
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if (flags & ADBREQ_SYNC) {
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WARN_ON(done);
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req->done = adb_sync_req_done;
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req->arg = ∁
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init_completion(&comp);
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}
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rc = adb_controller->send_request(req, 0);
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if ((flags & ADBREQ_SYNC) && !rc && !req->complete)
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wait_for_completion(&comp);
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return rc;
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}
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EXPORT_SYMBOL(adb_request);
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/* Ultimately this should return the number of devices with
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the given default id.
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And it does it now ! Note: changed behaviour: This function
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will now register if default_id _and_ handler_id both match
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but handler_id can be left to 0 to match with default_id only.
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When handler_id is set, this function will try to adjust
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the handler_id id it doesn't match. */
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int
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adb_register(int default_id, int handler_id, struct adb_ids *ids,
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void (*handler)(unsigned char *, int, int))
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{
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int i;
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mutex_lock(&adb_handler_mutex);
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ids->nids = 0;
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for (i = 1; i < 16; i++) {
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if ((adb_handler[i].original_address == default_id) &&
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(!handler_id || (handler_id == adb_handler[i].handler_id) ||
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try_handler_change(i, handler_id))) {
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if (adb_handler[i].handler != 0) {
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pr_err("Two handlers for ADB device %d\n",
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default_id);
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continue;
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}
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write_lock_irq(&adb_handler_lock);
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adb_handler[i].handler = handler;
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write_unlock_irq(&adb_handler_lock);
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ids->id[ids->nids++] = i;
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}
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}
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mutex_unlock(&adb_handler_mutex);
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return ids->nids;
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}
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EXPORT_SYMBOL(adb_register);
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int
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adb_unregister(int index)
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{
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int ret = -ENODEV;
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mutex_lock(&adb_handler_mutex);
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write_lock_irq(&adb_handler_lock);
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if (adb_handler[index].handler) {
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while(adb_handler[index].busy) {
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write_unlock_irq(&adb_handler_lock);
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yield();
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write_lock_irq(&adb_handler_lock);
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}
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ret = 0;
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adb_handler[index].handler = NULL;
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}
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write_unlock_irq(&adb_handler_lock);
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mutex_unlock(&adb_handler_mutex);
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return ret;
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}
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EXPORT_SYMBOL(adb_unregister);
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void
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adb_input(unsigned char *buf, int nb, int autopoll)
|
|
{
|
|
int i, id;
|
|
static int dump_adb_input;
|
|
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) {
|
|
pr_info("adb packet: ");
|
|
for (i = 0; i < nb; ++i)
|
|
pr_cont(" %x", buf[i]);
|
|
pr_cont(", 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);
|
|
if (ret)
|
|
pr_debug("adb handler change: [%d] 0x%X\n", address, new_id);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(adb_try_handler_change);
|
|
|
|
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;
|
|
DECLARE_WAITQUEUE(wait, current);
|
|
unsigned long flags;
|
|
|
|
if (count < 2)
|
|
return -EINVAL;
|
|
if (count > sizeof(req->reply))
|
|
count = sizeof(req->reply);
|
|
|
|
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;
|
|
|
|
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,
|
|
};
|
|
|
|
#ifdef CONFIG_PM
|
|
static const struct dev_pm_ops adb_dev_pm_ops = {
|
|
.suspend = adb_suspend,
|
|
.resume = adb_resume,
|
|
/* Hibernate hooks */
|
|
.freeze = adb_freeze,
|
|
.thaw = adb_resume,
|
|
.poweroff = adb_poweroff,
|
|
.restore = adb_resume,
|
|
};
|
|
#endif
|
|
|
|
static struct platform_driver adb_pfdrv = {
|
|
.driver = {
|
|
.name = "adb",
|
|
#ifdef CONFIG_PM
|
|
.pm = &adb_dev_pm_ops,
|
|
#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)) {
|
|
pr_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);
|
|
}
|