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5
6#include <linux/tty.h>
7#include <linux/tty_driver.h>
8#include <linux/tty_flip.h>
9
10#include "bcm_vk.h"
11
12
13#define BAR1_TTYVK_BASE_OFFSET 0x300000
14
15#define BAR1_TTYVK_CHAN_OFFSET 0x100000
16
17#define BAR1_TTYVK_BASE(index) (BAR1_TTYVK_BASE_OFFSET + \
18 ((index) * BAR1_TTYVK_CHAN_OFFSET * 2))
19
20#define TO_TTYK_BASE(index) BAR1_TTYVK_BASE(index)
21#define FROM_TTYK_BASE(index) (BAR1_TTYVK_BASE(index) + \
22 BAR1_TTYVK_CHAN_OFFSET)
23
24struct bcm_vk_tty_chan {
25 u32 reserved;
26 u32 size;
27 u32 wr;
28 u32 rd;
29 u32 *data;
30};
31
32#define VK_BAR_CHAN(v, DIR, e) ((v)->DIR##_offset \
33 + offsetof(struct bcm_vk_tty_chan, e))
34#define VK_BAR_CHAN_SIZE(v, DIR) VK_BAR_CHAN(v, DIR, size)
35#define VK_BAR_CHAN_WR(v, DIR) VK_BAR_CHAN(v, DIR, wr)
36#define VK_BAR_CHAN_RD(v, DIR) VK_BAR_CHAN(v, DIR, rd)
37#define VK_BAR_CHAN_DATA(v, DIR, off) (VK_BAR_CHAN(v, DIR, data) + (off))
38
39#define VK_BAR0_REGSEG_TTY_DB_OFFSET 0x86c
40
41
42#define SERIAL_TIMER_VALUE (HZ / 10)
43
44static void bcm_vk_tty_poll(struct timer_list *t)
45{
46 struct bcm_vk *vk = from_timer(vk, t, serial_timer);
47
48 queue_work(vk->tty_wq_thread, &vk->tty_wq_work);
49 mod_timer(&vk->serial_timer, jiffies + SERIAL_TIMER_VALUE);
50}
51
52irqreturn_t bcm_vk_tty_irqhandler(int irq, void *dev_id)
53{
54 struct bcm_vk *vk = dev_id;
55
56 queue_work(vk->tty_wq_thread, &vk->tty_wq_work);
57
58 return IRQ_HANDLED;
59}
60
61static void bcm_vk_tty_wq_handler(struct work_struct *work)
62{
63 struct bcm_vk *vk = container_of(work, struct bcm_vk, tty_wq_work);
64 struct bcm_vk_tty *vktty;
65 int card_status;
66 int count;
67 unsigned char c;
68 int i;
69 int wr;
70
71 card_status = vkread32(vk, BAR_0, BAR_CARD_STATUS);
72 if (BCM_VK_INTF_IS_DOWN(card_status))
73 return;
74
75 for (i = 0; i < BCM_VK_NUM_TTY; i++) {
76 count = 0;
77
78 if ((card_status & BIT(i)) == 0)
79 continue;
80
81 vktty = &vk->tty[i];
82
83
84 if (!vktty->is_opened)
85 continue;
86
87
88 wr = vkread32(vk, BAR_1, VK_BAR_CHAN_WR(vktty, from));
89
90
91 if (vktty->from_size == 0)
92 continue;
93
94 if (wr >= vktty->from_size) {
95 dev_err(&vk->pdev->dev,
96 "ERROR: wq handler ttyVK%d wr:0x%x > 0x%x\n",
97 i, wr, vktty->from_size);
98
99 continue;
100 }
101
102
103
104
105
106 while (vk->tty[i].rd != wr) {
107 c = vkread8(vk, BAR_1,
108 VK_BAR_CHAN_DATA(vktty, from, vktty->rd));
109 vktty->rd++;
110 if (vktty->rd >= vktty->from_size)
111 vktty->rd = 0;
112 tty_insert_flip_char(&vktty->port, c, TTY_NORMAL);
113 count++;
114 }
115
116 if (count) {
117 tty_flip_buffer_push(&vktty->port);
118
119
120 vkwrite32(vk, vktty->rd, BAR_1,
121 VK_BAR_CHAN_RD(vktty, from));
122 }
123 }
124}
125
126static int bcm_vk_tty_open(struct tty_struct *tty, struct file *file)
127{
128 int card_status;
129 struct bcm_vk *vk;
130 struct bcm_vk_tty *vktty;
131 int index;
132
133
134 tty->driver_data = NULL;
135
136 vk = (struct bcm_vk *)dev_get_drvdata(tty->dev);
137 index = tty->index;
138
139 if (index >= BCM_VK_NUM_TTY)
140 return -EINVAL;
141
142 vktty = &vk->tty[index];
143
144 vktty->pid = task_pid_nr(current);
145 vktty->to_offset = TO_TTYK_BASE(index);
146 vktty->from_offset = FROM_TTYK_BASE(index);
147
148
149 card_status = vkread32(vk, BAR_0, BAR_CARD_STATUS);
150 if (BCM_VK_INTF_IS_DOWN(card_status) || ((card_status & BIT(index)) == 0))
151 return -EBUSY;
152
153
154
155
156
157 vktty->to_size = vkread32(vk, BAR_1, VK_BAR_CHAN_SIZE(vktty, to));
158 vktty->wr = vkread32(vk, BAR_1, VK_BAR_CHAN_WR(vktty, to));
159 vktty->from_size = vkread32(vk, BAR_1, VK_BAR_CHAN_SIZE(vktty, from));
160 vktty->rd = vkread32(vk, BAR_1, VK_BAR_CHAN_RD(vktty, from));
161 vktty->is_opened = true;
162
163 if (tty->count == 1 && !vktty->irq_enabled) {
164 timer_setup(&vk->serial_timer, bcm_vk_tty_poll, 0);
165 mod_timer(&vk->serial_timer, jiffies + SERIAL_TIMER_VALUE);
166 }
167 return 0;
168}
169
170static void bcm_vk_tty_close(struct tty_struct *tty, struct file *file)
171{
172 struct bcm_vk *vk = dev_get_drvdata(tty->dev);
173
174 if (tty->index >= BCM_VK_NUM_TTY)
175 return;
176
177 vk->tty[tty->index].is_opened = false;
178
179 if (tty->count == 1)
180 del_timer_sync(&vk->serial_timer);
181}
182
183static void bcm_vk_tty_doorbell(struct bcm_vk *vk, u32 db_val)
184{
185 vkwrite32(vk, db_val, BAR_0,
186 VK_BAR0_REGSEG_DB_BASE + VK_BAR0_REGSEG_TTY_DB_OFFSET);
187}
188
189static int bcm_vk_tty_write(struct tty_struct *tty,
190 const unsigned char *buffer,
191 int count)
192{
193 int index;
194 struct bcm_vk *vk;
195 struct bcm_vk_tty *vktty;
196 int i;
197
198 index = tty->index;
199 vk = dev_get_drvdata(tty->dev);
200 vktty = &vk->tty[index];
201
202
203 for (i = 0; i < count; i++) {
204 vkwrite8(vk, buffer[i], BAR_1,
205 VK_BAR_CHAN_DATA(vktty, to, vktty->wr));
206 vktty->wr++;
207 if (vktty->wr >= vktty->to_size)
208 vktty->wr = 0;
209 }
210
211 vkwrite32(vk, vktty->wr, BAR_1, VK_BAR_CHAN_WR(vktty, to));
212 bcm_vk_tty_doorbell(vk, 0);
213
214 return count;
215}
216
217static unsigned int bcm_vk_tty_write_room(struct tty_struct *tty)
218{
219 struct bcm_vk *vk = dev_get_drvdata(tty->dev);
220
221 return vk->tty[tty->index].to_size - 1;
222}
223
224static const struct tty_operations serial_ops = {
225 .open = bcm_vk_tty_open,
226 .close = bcm_vk_tty_close,
227 .write = bcm_vk_tty_write,
228 .write_room = bcm_vk_tty_write_room,
229};
230
231int bcm_vk_tty_init(struct bcm_vk *vk, char *name)
232{
233 int i;
234 int err;
235 struct tty_driver *tty_drv;
236 struct device *dev = &vk->pdev->dev;
237
238 tty_drv = tty_alloc_driver
239 (BCM_VK_NUM_TTY,
240 TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV);
241 if (IS_ERR(tty_drv))
242 return PTR_ERR(tty_drv);
243
244
245 vk->tty_drv = tty_drv;
246
247
248 tty_drv->driver_name = KBUILD_MODNAME;
249 tty_drv->name = kstrdup(name, GFP_KERNEL);
250 if (!tty_drv->name) {
251 err = -ENOMEM;
252 goto err_tty_driver_kref_put;
253 }
254 tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
255 tty_drv->subtype = SERIAL_TYPE_NORMAL;
256 tty_drv->init_termios = tty_std_termios;
257 tty_set_operations(tty_drv, &serial_ops);
258
259
260 err = tty_register_driver(tty_drv);
261 if (err) {
262 dev_err(dev, "tty_register_driver failed\n");
263 goto err_kfree_tty_name;
264 }
265
266 for (i = 0; i < BCM_VK_NUM_TTY; i++) {
267 struct device *tty_dev;
268
269 tty_port_init(&vk->tty[i].port);
270 tty_dev = tty_port_register_device_attr(&vk->tty[i].port,
271 tty_drv, i, dev, vk,
272 NULL);
273 if (IS_ERR(tty_dev)) {
274 err = PTR_ERR(tty_dev);
275 goto unwind;
276 }
277 vk->tty[i].is_opened = false;
278 }
279
280 INIT_WORK(&vk->tty_wq_work, bcm_vk_tty_wq_handler);
281 vk->tty_wq_thread = create_singlethread_workqueue("tty");
282 if (!vk->tty_wq_thread) {
283 dev_err(dev, "Fail to create tty workqueue thread\n");
284 err = -ENOMEM;
285 goto unwind;
286 }
287 return 0;
288
289unwind:
290 while (--i >= 0)
291 tty_port_unregister_device(&vk->tty[i].port, tty_drv, i);
292 tty_unregister_driver(tty_drv);
293
294err_kfree_tty_name:
295 kfree(tty_drv->name);
296 tty_drv->name = NULL;
297
298err_tty_driver_kref_put:
299 tty_driver_kref_put(tty_drv);
300
301 return err;
302}
303
304void bcm_vk_tty_exit(struct bcm_vk *vk)
305{
306 int i;
307
308 del_timer_sync(&vk->serial_timer);
309 for (i = 0; i < BCM_VK_NUM_TTY; ++i) {
310 tty_port_unregister_device(&vk->tty[i].port,
311 vk->tty_drv,
312 i);
313 tty_port_destroy(&vk->tty[i].port);
314 }
315 tty_unregister_driver(vk->tty_drv);
316
317 kfree(vk->tty_drv->name);
318 vk->tty_drv->name = NULL;
319
320 tty_driver_kref_put(vk->tty_drv);
321}
322
323void bcm_vk_tty_terminate_tty_user(struct bcm_vk *vk)
324{
325 struct bcm_vk_tty *vktty;
326 int i;
327
328 for (i = 0; i < BCM_VK_NUM_TTY; ++i) {
329 vktty = &vk->tty[i];
330 if (vktty->pid)
331 kill_pid(find_vpid(vktty->pid), SIGKILL, 1);
332 }
333}
334
335void bcm_vk_tty_wq_exit(struct bcm_vk *vk)
336{
337 cancel_work_sync(&vk->tty_wq_work);
338 destroy_workqueue(vk->tty_wq_thread);
339}
340