diff options
Diffstat (limited to 'goldfish_pipe_base.c')
| -rw-r--r-- | goldfish_pipe_base.c | 146 |
1 files changed, 0 insertions, 146 deletions
diff --git a/goldfish_pipe_base.c b/goldfish_pipe_base.c deleted file mode 100644 index 9a59f4f..0000000 --- a/goldfish_pipe_base.c +++ /dev/null @@ -1,146 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Copyright (C) 2012 Intel, Inc. - * Copyright (C) 2013 Intel, Inc. - * Copyright (C) 2014 Linaro Limited - * Copyright (C) 2011-2016 Google, Inc. - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - */ - -/* This source file contains the implementation of a special device driver - * that intends to provide a *very* fast communication channel between the - * guest system and the QEMU emulator. - * - * Usage from the guest is simply the following (error handling simplified): - * - * int fd = open("/dev/qemu_pipe",O_RDWR); - * .... write() or read() through the pipe. - * - * This driver doesn't deal with the exact protocol used during the session. - * It is intended to be as simple as something like: - * - * // do this _just_ after opening the fd to connect to a specific - * // emulator service. - * const char* msg = "<pipename>"; - * if (write(fd, msg, strlen(msg)+1) < 0) { - * ... could not connect to <pipename> service - * close(fd); - * } - * - * // after this, simply read() and write() to communicate with the - * // service. Exact protocol details left as an exercise to the reader. - * - * This driver is very fast because it doesn't copy any data through - * intermediate buffers, since the emulator is capable of translating - * guest user addresses into host ones. - * - * Note that we must however ensure that each user page involved in the - * exchange is properly mapped during a transfer. - */ - -#include "defconfig_test.h" - -#include <linux/module.h> -#include <linux/mod_devicetable.h> -#include <linux/interrupt.h> -#include <linux/kernel.h> -#include <linux/platform_device.h> -#include <linux/io.h> -#include <linux/acpi.h> -#include "goldfish_pipe_qemu.h" -#include "goldfish_pipe.h" - -/* - * Update this when something changes in the driver's behavior so the host - * can benefit from knowing it - * Notes: - * version 2 was an intermediate release and isn't supported anymore. - * version 3 is goldfish_pipe_v2 without DMA support. - * version 4 (current) is goldfish_pipe_v2 with DMA support. - */ -enum { - PIPE_DRIVER_VERSION = 4, - PIPE_CURRENT_DEVICE_VERSION = 2 -}; - -static int goldfish_pipe_probe(struct platform_device *pdev) -{ - struct resource *r; - char __iomem *base; - int irq; - int version; - - r = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!r || resource_size(r) < PAGE_SIZE) { - dev_err(&pdev->dev, "can't allocate i/o page\n"); - return -EINVAL; - } - base = devm_ioremap(&pdev->dev, r->start, PAGE_SIZE); - if (!base) { - dev_err(&pdev->dev, "ioremap failed\n"); - return -EINVAL; - } - - r = platform_get_resource(pdev, IORESOURCE_IRQ, 0); - if (!r) - return -EINVAL; - - irq = r->start; - - /* - * Exchange the versions with the host device - * - * Note: v1 driver used to not report its version, so we write it before - * reading device version back: this allows the host implementation to - * detect the old driver (if there was no version write before read). - */ - writel(PIPE_DRIVER_VERSION, base + PIPE_V2_REG_VERSION); - version = readl(base + PIPE_V2_REG_VERSION); - - if (version < PIPE_CURRENT_DEVICE_VERSION) - return goldfish_pipe_device_v1_init(pdev, base, irq); - else - return goldfish_pipe_device_v2_init(pdev, base, irq); -} - -static int goldfish_pipe_remove(struct platform_device *pdev) -{ - struct goldfish_pipe_dev_base *dev = platform_get_drvdata(pdev); - - return dev->deinit(dev, pdev); -} - -static const struct acpi_device_id goldfish_pipe_acpi_match[] = { - { "GFSH0003", 0 }, - { }, -}; -MODULE_DEVICE_TABLE(acpi, goldfish_pipe_acpi_match); - -static const struct of_device_id goldfish_pipe_of_match[] = { - { .compatible = "google,android-pipe", }, - {}, -}; -MODULE_DEVICE_TABLE(of, goldfish_pipe_of_match); - -static struct platform_driver goldfish_pipe_driver = { - .probe = goldfish_pipe_probe, - .remove = goldfish_pipe_remove, - .driver = { - .name = "goldfish_pipe", - .of_match_table = goldfish_pipe_of_match, - .acpi_match_table = ACPI_PTR(goldfish_pipe_acpi_match), - } -}; - -module_platform_driver(goldfish_pipe_driver); -MODULE_AUTHOR("David Turner <digit@google.com>"); -MODULE_LICENSE("GPL v2"); |