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16#include <linux/console.h>
17#include <linux/interrupt.h>
18#include <linux/platform_device.h>
19#include <linux/tty.h>
20#include <linux/tty_flip.h>
21#include <linux/slab.h>
22#include <linux/io.h>
23#include <linux/module.h>
24#include <linux/goldfish.h>
25
26enum {
27 GOLDFISH_TTY_PUT_CHAR = 0x00,
28 GOLDFISH_TTY_BYTES_READY = 0x04,
29 GOLDFISH_TTY_CMD = 0x08,
30
31 GOLDFISH_TTY_DATA_PTR = 0x10,
32 GOLDFISH_TTY_DATA_LEN = 0x14,
33 GOLDFISH_TTY_DATA_PTR_HIGH = 0x18,
34
35 GOLDFISH_TTY_CMD_INT_DISABLE = 0,
36 GOLDFISH_TTY_CMD_INT_ENABLE = 1,
37 GOLDFISH_TTY_CMD_WRITE_BUFFER = 2,
38 GOLDFISH_TTY_CMD_READ_BUFFER = 3,
39};
40
41struct goldfish_tty {
42 struct tty_port port;
43 spinlock_t lock;
44 void __iomem *base;
45 u32 irq;
46 int opencount;
47 struct console console;
48};
49
50static DEFINE_MUTEX(goldfish_tty_lock);
51static struct tty_driver *goldfish_tty_driver;
52static u32 goldfish_tty_line_count = 8;
53static u32 goldfish_tty_current_line_count;
54static struct goldfish_tty *goldfish_ttys;
55
56static void goldfish_tty_do_write(int line, const char *buf, unsigned count)
57{
58 unsigned long irq_flags;
59 struct goldfish_tty *qtty = &goldfish_ttys[line];
60 void __iomem *base = qtty->base;
61 spin_lock_irqsave(&qtty->lock, irq_flags);
62 gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
63 base + GOLDFISH_TTY_DATA_PTR_HIGH);
64 writel(count, base + GOLDFISH_TTY_DATA_LEN);
65 writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_CMD);
66 spin_unlock_irqrestore(&qtty->lock, irq_flags);
67}
68
69static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
70{
71 struct platform_device *pdev = dev_id;
72 struct goldfish_tty *qtty = &goldfish_ttys[pdev->id];
73 void __iomem *base = qtty->base;
74 unsigned long irq_flags;
75 unsigned char *buf;
76 u32 count;
77
78 count = readl(base + GOLDFISH_TTY_BYTES_READY);
79 if (count == 0)
80 return IRQ_NONE;
81
82 count = tty_prepare_flip_string(&qtty->port, &buf, count);
83 spin_lock_irqsave(&qtty->lock, irq_flags);
84 gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
85 base + GOLDFISH_TTY_DATA_PTR_HIGH);
86 writel(count, base + GOLDFISH_TTY_DATA_LEN);
87 writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
88 spin_unlock_irqrestore(&qtty->lock, irq_flags);
89 tty_schedule_flip(&qtty->port);
90 return IRQ_HANDLED;
91}
92
93static int goldfish_tty_activate(struct tty_port *port, struct tty_struct *tty)
94{
95 struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
96 port);
97 writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_CMD);
98 return 0;
99}
100
101static void goldfish_tty_shutdown(struct tty_port *port)
102{
103 struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
104 port);
105 writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_CMD);
106}
107
108static int goldfish_tty_open(struct tty_struct *tty, struct file *filp)
109{
110 struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
111 return tty_port_open(&qtty->port, tty, filp);
112}
113
114static void goldfish_tty_close(struct tty_struct *tty, struct file *filp)
115{
116 tty_port_close(tty->port, tty, filp);
117}
118
119static void goldfish_tty_hangup(struct tty_struct *tty)
120{
121 tty_port_hangup(tty->port);
122}
123
124static int goldfish_tty_write(struct tty_struct *tty, const unsigned char *buf,
125 int count)
126{
127 goldfish_tty_do_write(tty->index, buf, count);
128 return count;
129}
130
131static int goldfish_tty_write_room(struct tty_struct *tty)
132{
133 return 0x10000;
134}
135
136static int goldfish_tty_chars_in_buffer(struct tty_struct *tty)
137{
138 struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
139 void __iomem *base = qtty->base;
140 return readl(base + GOLDFISH_TTY_BYTES_READY);
141}
142
143static void goldfish_tty_console_write(struct console *co, const char *b,
144 unsigned count)
145{
146 goldfish_tty_do_write(co->index, b, count);
147}
148
149static struct tty_driver *goldfish_tty_console_device(struct console *c,
150 int *index)
151{
152 *index = c->index;
153 return goldfish_tty_driver;
154}
155
156static int goldfish_tty_console_setup(struct console *co, char *options)
157{
158 if ((unsigned)co->index >= goldfish_tty_line_count)
159 return -ENODEV;
160 if (!goldfish_ttys[co->index].base)
161 return -ENODEV;
162 return 0;
163}
164
165static struct tty_port_operations goldfish_port_ops = {
166 .activate = goldfish_tty_activate,
167 .shutdown = goldfish_tty_shutdown
168};
169
170static const struct tty_operations goldfish_tty_ops = {
171 .open = goldfish_tty_open,
172 .close = goldfish_tty_close,
173 .hangup = goldfish_tty_hangup,
174 .write = goldfish_tty_write,
175 .write_room = goldfish_tty_write_room,
176 .chars_in_buffer = goldfish_tty_chars_in_buffer,
177};
178
179static int goldfish_tty_create_driver(void)
180{
181 int ret;
182 struct tty_driver *tty;
183
184 goldfish_ttys = kzalloc(sizeof(*goldfish_ttys) *
185 goldfish_tty_line_count, GFP_KERNEL);
186 if (goldfish_ttys == NULL) {
187 ret = -ENOMEM;
188 goto err_alloc_goldfish_ttys_failed;
189 }
190 tty = alloc_tty_driver(goldfish_tty_line_count);
191 if (tty == NULL) {
192 ret = -ENOMEM;
193 goto err_alloc_tty_driver_failed;
194 }
195 tty->driver_name = "goldfish";
196 tty->name = "ttyGF";
197 tty->type = TTY_DRIVER_TYPE_SERIAL;
198 tty->subtype = SERIAL_TYPE_NORMAL;
199 tty->init_termios = tty_std_termios;
200 tty->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
201 TTY_DRIVER_DYNAMIC_DEV;
202 tty_set_operations(tty, &goldfish_tty_ops);
203 ret = tty_register_driver(tty);
204 if (ret)
205 goto err_tty_register_driver_failed;
206
207 goldfish_tty_driver = tty;
208 return 0;
209
210err_tty_register_driver_failed:
211 put_tty_driver(tty);
212err_alloc_tty_driver_failed:
213 kfree(goldfish_ttys);
214 goldfish_ttys = NULL;
215err_alloc_goldfish_ttys_failed:
216 return ret;
217}
218
219static void goldfish_tty_delete_driver(void)
220{
221 tty_unregister_driver(goldfish_tty_driver);
222 put_tty_driver(goldfish_tty_driver);
223 goldfish_tty_driver = NULL;
224 kfree(goldfish_ttys);
225 goldfish_ttys = NULL;
226}
227
228static int goldfish_tty_probe(struct platform_device *pdev)
229{
230 struct goldfish_tty *qtty;
231 int ret = -EINVAL;
232 struct resource *r;
233 struct device *ttydev;
234 void __iomem *base;
235 u32 irq;
236
237 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
238 if (r == NULL)
239 return -EINVAL;
240
241 base = ioremap(r->start, 0x1000);
242 if (base == NULL)
243 pr_err("goldfish_tty: unable to remap base\n");
244
245 r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
246 if (r == NULL)
247 goto err_unmap;
248
249 irq = r->start;
250
251 if (pdev->id >= goldfish_tty_line_count)
252 goto err_unmap;
253
254 mutex_lock(&goldfish_tty_lock);
255 if (goldfish_tty_current_line_count == 0) {
256 ret = goldfish_tty_create_driver();
257 if (ret)
258 goto err_create_driver_failed;
259 }
260 goldfish_tty_current_line_count++;
261
262 qtty = &goldfish_ttys[pdev->id];
263 spin_lock_init(&qtty->lock);
264 tty_port_init(&qtty->port);
265 qtty->port.ops = &goldfish_port_ops;
266 qtty->base = base;
267 qtty->irq = irq;
268
269 writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_CMD);
270
271 ret = request_irq(irq, goldfish_tty_interrupt, IRQF_SHARED,
272 "goldfish_tty", pdev);
273 if (ret)
274 goto err_request_irq_failed;
275
276
277 ttydev = tty_port_register_device(&qtty->port, goldfish_tty_driver,
278 pdev->id, &pdev->dev);
279 if (IS_ERR(ttydev)) {
280 ret = PTR_ERR(ttydev);
281 goto err_tty_register_device_failed;
282 }
283
284 strcpy(qtty->console.name, "ttyGF");
285 qtty->console.write = goldfish_tty_console_write;
286 qtty->console.device = goldfish_tty_console_device;
287 qtty->console.setup = goldfish_tty_console_setup;
288 qtty->console.flags = CON_PRINTBUFFER;
289 qtty->console.index = pdev->id;
290 register_console(&qtty->console);
291
292 mutex_unlock(&goldfish_tty_lock);
293 return 0;
294
295err_tty_register_device_failed:
296 free_irq(irq, pdev);
297err_request_irq_failed:
298 goldfish_tty_current_line_count--;
299 if (goldfish_tty_current_line_count == 0)
300 goldfish_tty_delete_driver();
301err_create_driver_failed:
302 mutex_unlock(&goldfish_tty_lock);
303err_unmap:
304 iounmap(base);
305 return ret;
306}
307
308static int goldfish_tty_remove(struct platform_device *pdev)
309{
310 struct goldfish_tty *qtty;
311
312 mutex_lock(&goldfish_tty_lock);
313
314 qtty = &goldfish_ttys[pdev->id];
315 unregister_console(&qtty->console);
316 tty_unregister_device(goldfish_tty_driver, pdev->id);
317 iounmap(qtty->base);
318 qtty->base = NULL;
319 free_irq(qtty->irq, pdev);
320 goldfish_tty_current_line_count--;
321 if (goldfish_tty_current_line_count == 0)
322 goldfish_tty_delete_driver();
323 mutex_unlock(&goldfish_tty_lock);
324 return 0;
325}
326
327static struct platform_driver goldfish_tty_platform_driver = {
328 .probe = goldfish_tty_probe,
329 .remove = goldfish_tty_remove,
330 .driver = {
331 .name = "goldfish_tty"
332 }
333};
334
335module_platform_driver(goldfish_tty_platform_driver);
336
337MODULE_LICENSE("GPL v2");
338
