1 /* 2 * Copyright (C) 2016 Google, Inc. 3 * 4 * This software is licensed under the terms of the GNU General Public 5 * License version 2, as published by the Free Software Foundation, and 6 * may be copied, distributed, and modified under those terms. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 */ 14 #ifndef GOLDFISH_PIPE_H 15 #define GOLDFISH_PIPE_H 16 17 #include <linux/module.h> 18 #include <linux/interrupt.h> 19 #include <linux/kernel.h> 20 #include <linux/spinlock.h> 21 #include <linux/miscdevice.h> 22 #include <linux/platform_device.h> 23 #include <linux/poll.h> 24 #include <linux/sched.h> 25 #include <linux/bitops.h> 26 #include <linux/slab.h> 27 #include <linux/io.h> 28 #include <linux/goldfish.h> 29 #include <linux/dma-mapping.h> 30 #include <linux/mm.h> 31 #include <linux/acpi.h> 32 33 34 /* Initialize the legacy version of the pipe device driver */ 35 int goldfish_pipe_device_init_v1(struct platform_device *pdev); 36 37 /* Deinitialize the legacy version of the pipe device driver */ 38 void goldfish_pipe_device_deinit_v1(struct platform_device *pdev); 39 40 /* Forward declarations for the device struct */ 41 struct goldfish_pipe; 42 struct goldfish_pipe_device_buffers; 43 44 /* The global driver data. Holds a reference to the i/o page used to 45 * communicate with the emulator, and a wake queue for blocked tasks 46 * waiting to be awoken. 47 */ 48 struct goldfish_pipe_dev { 49 /* 50 * Global device spinlock. Protects the following members: 51 * - pipes, pipes_capacity 52 * - [*pipes, *pipes + pipes_capacity) - array data 53 * - first_signalled_pipe, 54 * goldfish_pipe::prev_signalled, 55 * goldfish_pipe::next_signalled, 56 * goldfish_pipe::signalled_flags - all singnalled-related fields, 57 * in all allocated pipes 58 * - open_command_params - PIPE_CMD_OPEN-related buffers 59 * 60 * It looks like a lot of different fields, but the trick is that the only 61 * operation that happens often is the signalled pipes array manipulation. 62 * That's why it's OK for now to keep the rest of the fields under the same 63 * lock. If we notice too much contention because of PIPE_CMD_OPEN, 64 * then we should add a separate lock there. 65 */ 66 spinlock_t lock; 67 68 /* 69 * Array of the pipes of |pipes_capacity| elements, 70 * indexed by goldfish_pipe::id 71 */ 72 struct goldfish_pipe **pipes; 73 u32 pipes_capacity; 74 75 /* Pointers to the buffers host uses for interaction with this driver */ 76 struct goldfish_pipe_dev_buffers *buffers; 77 78 /* Head of a doubly linked list of signalled pipes */ 79 struct goldfish_pipe *first_signalled_pipe; 80 81 /* Some device-specific data */ 82 int irq; 83 int version; 84 unsigned char __iomem *base; 85 86 /* v1-specific access parameters */ 87 struct access_params *aps; 88 }; 89 90 extern struct goldfish_pipe_dev pipe_dev[1]; 91 92 #endif /* GOLDFISH_PIPE_H */ 93