/* * Copyright (C) 2007 Google, Inc. * Copyright (C) 2012 Intel, 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. * */ #include <linux/console.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/slab.h> #include <linux/io.h> #include <linux/module.h> #include <linux/goldfish.h> enum { GOLDFISH_TTY_PUT_CHAR = 0x00, GOLDFISH_TTY_BYTES_READY = 0x04, GOLDFISH_TTY_CMD = 0x08, GOLDFISH_TTY_DATA_PTR = 0x10, GOLDFISH_TTY_DATA_LEN = 0x14, GOLDFISH_TTY_DATA_PTR_HIGH = 0x18, GOLDFISH_TTY_CMD_INT_DISABLE = 0, GOLDFISH_TTY_CMD_INT_ENABLE = 1, GOLDFISH_TTY_CMD_WRITE_BUFFER = 2, GOLDFISH_TTY_CMD_READ_BUFFER = 3, }; struct goldfish_tty { struct tty_port port; spinlock_t lock; void __iomem *base; u32 irq; int opencount; struct console console; }; static DEFINE_MUTEX(goldfish_tty_lock); static struct tty_driver *goldfish_tty_driver; static u32 goldfish_tty_line_count = 8; static u32 goldfish_tty_current_line_count; static struct goldfish_tty *goldfish_ttys; static void goldfish_tty_do_write(int line, const char *buf, unsigned count) { unsigned long irq_flags; struct goldfish_tty *qtty = &goldfish_ttys[line]; void __iomem *base = qtty->base; spin_lock_irqsave(&qtty->lock, irq_flags); gf_write64((u64)buf, base + GOLDFISH_TTY_DATA_PTR, base + GOLDFISH_TTY_DATA_PTR_HIGH); writel(count, base + GOLDFISH_TTY_DATA_LEN); writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_CMD); spin_unlock_irqrestore(&qtty->lock, irq_flags); } static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id) { struct platform_device *pdev = dev_id; struct goldfish_tty *qtty = &goldfish_ttys[pdev->id]; void __iomem *base = qtty->base; unsigned long irq_flags; unsigned char *buf; u32 count; count = readl(base + GOLDFISH_TTY_BYTES_READY); if (count == 0) return IRQ_NONE; count = tty_prepare_flip_string(&qtty->port, &buf, count); spin_lock_irqsave(&qtty->lock, irq_flags); gf_write64((u64)buf, base + GOLDFISH_TTY_DATA_PTR, base + GOLDFISH_TTY_DATA_PTR_HIGH); writel(count, base + GOLDFISH_TTY_DATA_LEN); writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD); spin_unlock_irqrestore(&qtty->lock, irq_flags); tty_schedule_flip(&qtty->port); return IRQ_HANDLED; } static int goldfish_tty_activate(struct tty_port *port, struct tty_struct *tty) { struct goldfish_tty *qtty = container_of(port, struct goldfish_tty, port); writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_CMD); return 0; } static void goldfish_tty_shutdown(struct tty_port *port) { struct goldfish_tty *qtty = container_of(port, struct goldfish_tty, port); writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_CMD); } static int goldfish_tty_open(struct tty_struct *tty, struct file *filp) { struct goldfish_tty *qtty = &goldfish_ttys[tty->index]; return tty_port_open(&qtty->port, tty, filp); } static void goldfish_tty_close(struct tty_struct *tty, struct file *filp) { tty_port_close(tty->port, tty, filp); } static void goldfish_tty_hangup(struct tty_struct *tty) { tty_port_hangup(tty->port); } static int goldfish_tty_write(struct tty_struct *tty, const unsigned char *buf, int count) { goldfish_tty_do_write(tty->index, buf, count); return count; } static int goldfish_tty_write_room(struct tty_struct *tty) { return 0x10000; } static int goldfish_tty_chars_in_buffer(struct tty_struct *tty) { struct goldfish_tty *qtty = &goldfish_ttys[tty->index]; void __iomem *base = qtty->base; return readl(base + GOLDFISH_TTY_BYTES_READY); } static void goldfish_tty_console_write(struct console *co, const char *b, unsigned count) { goldfish_tty_do_write(co->index, b, count); } static struct tty_driver *goldfish_tty_console_device(struct console *c, int *index) { *index = c->index; return goldfish_tty_driver; } static int goldfish_tty_console_setup(struct console *co, char *options) { if ((unsigned)co->index >= goldfish_tty_line_count) return -ENODEV; if (!goldfish_ttys[co->index].base) return -ENODEV; return 0; } static struct tty_port_operations goldfish_port_ops = { .activate = goldfish_tty_activate, .shutdown = goldfish_tty_shutdown }; static const struct tty_operations goldfish_tty_ops = { .open = goldfish_tty_open, .close = goldfish_tty_close, .hangup = goldfish_tty_hangup, .write = goldfish_tty_write, .write_room = goldfish_tty_write_room, .chars_in_buffer = goldfish_tty_chars_in_buffer, }; static int goldfish_tty_create_driver(void) { int ret; struct tty_driver *tty; goldfish_ttys = kzalloc(sizeof(*goldfish_ttys) * goldfish_tty_line_count, GFP_KERNEL); if (goldfish_ttys == NULL) { ret = -ENOMEM; goto err_alloc_goldfish_ttys_failed; } tty = alloc_tty_driver(goldfish_tty_line_count); if (tty == NULL) { ret = -ENOMEM; goto err_alloc_tty_driver_failed; } tty->driver_name = "goldfish"; tty->name = "ttyGF"; tty->type = TTY_DRIVER_TYPE_SERIAL; tty->subtype = SERIAL_TYPE_NORMAL; tty->init_termios = tty_std_termios; tty->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV; tty_set_operations(tty, &goldfish_tty_ops); ret = tty_register_driver(tty); if (ret) goto err_tty_register_driver_failed; goldfish_tty_driver = tty; return 0; err_tty_register_driver_failed: put_tty_driver(tty); err_alloc_tty_driver_failed: kfree(goldfish_ttys); goldfish_ttys = NULL; err_alloc_goldfish_ttys_failed: return ret; } static void goldfish_tty_delete_driver(void) { tty_unregister_driver(goldfish_tty_driver); put_tty_driver(goldfish_tty_driver); goldfish_tty_driver = NULL; kfree(goldfish_ttys); goldfish_ttys = NULL; } static int goldfish_tty_probe(struct platform_device *pdev) { struct goldfish_tty *qtty; int ret = -EINVAL; int i; struct resource *r; struct device *ttydev; void __iomem *base; u32 irq; r = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (r == NULL) return -EINVAL; base = ioremap(r->start, 0x1000); if (base == NULL) pr_err("goldfish_tty: unable to remap base\n"); r = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (r == NULL) goto err_unmap; irq = r->start; if (pdev->id >= goldfish_tty_line_count) goto err_unmap; mutex_lock(&goldfish_tty_lock); if (goldfish_tty_current_line_count == 0) { ret = goldfish_tty_create_driver(); if (ret) goto err_create_driver_failed; } goldfish_tty_current_line_count++; qtty = &goldfish_ttys[pdev->id]; spin_lock_init(&qtty->lock); tty_port_init(&qtty->port); qtty->port.ops = &goldfish_port_ops; qtty->base = base; qtty->irq = irq; writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_CMD); ret = request_irq(irq, goldfish_tty_interrupt, IRQF_SHARED, "goldfish_tty", pdev); if (ret) goto err_request_irq_failed; ttydev = tty_port_register_device(&qtty->port, goldfish_tty_driver, pdev->id, &pdev->dev); if (IS_ERR(ttydev)) { ret = PTR_ERR(ttydev); goto err_tty_register_device_failed; } strcpy(qtty->console.name, "ttyGF"); qtty->console.write = goldfish_tty_console_write; qtty->console.device = goldfish_tty_console_device; qtty->console.setup = goldfish_tty_console_setup; qtty->console.flags = CON_PRINTBUFFER; qtty->console.index = pdev->id; register_console(&qtty->console); mutex_unlock(&goldfish_tty_lock); return 0; tty_unregister_device(goldfish_tty_driver, i); err_tty_register_device_failed: free_irq(irq, pdev); err_request_irq_failed: goldfish_tty_current_line_count--; if (goldfish_tty_current_line_count == 0) goldfish_tty_delete_driver(); err_create_driver_failed: mutex_unlock(&goldfish_tty_lock); err_unmap: iounmap(base); return ret; } static int goldfish_tty_remove(struct platform_device *pdev) { struct goldfish_tty *qtty; mutex_lock(&goldfish_tty_lock); qtty = &goldfish_ttys[pdev->id]; unregister_console(&qtty->console); tty_unregister_device(goldfish_tty_driver, pdev->id); iounmap(qtty->base); qtty->base = NULL; free_irq(qtty->irq, pdev); goldfish_tty_current_line_count--; if (goldfish_tty_current_line_count == 0) goldfish_tty_delete_driver(); mutex_unlock(&goldfish_tty_lock); return 0; } static struct platform_driver goldfish_tty_platform_driver = { .probe = goldfish_tty_probe, .remove = goldfish_tty_remove, .driver = { .name = "goldfish_tty" } }; module_platform_driver(goldfish_tty_platform_driver); MODULE_LICENSE("GPL v2");