xref: /openbmc/linux/drivers/tty/goldfish.c (revision ac316725)
1e3b3d0f5SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
2666b7793SArve Hjønnevåg /*
3666b7793SArve Hjønnevåg  * Copyright (C) 2007 Google, Inc.
4666b7793SArve Hjønnevåg  * Copyright (C) 2012 Intel, Inc.
53840ed95SMiodrag Dinic  * Copyright (C) 2017 Imagination Technologies Ltd.
6666b7793SArve Hjønnevåg  */
7666b7793SArve Hjønnevåg 
8666b7793SArve Hjønnevåg #include <linux/console.h>
9666b7793SArve Hjønnevåg #include <linux/interrupt.h>
10666b7793SArve Hjønnevåg #include <linux/platform_device.h>
11666b7793SArve Hjønnevåg #include <linux/tty.h>
12666b7793SArve Hjønnevåg #include <linux/tty_flip.h>
13666b7793SArve Hjønnevåg #include <linux/slab.h>
14666b7793SArve Hjønnevåg #include <linux/io.h>
15666b7793SArve Hjønnevåg #include <linux/module.h>
16ac316725SRandy Dunlap #include <linux/mod_devicetable.h>
17e0f682e0SAlan #include <linux/goldfish.h>
187157d2beSMiodrag Dinic #include <linux/mm.h>
197157d2beSMiodrag Dinic #include <linux/dma-mapping.h>
203840ed95SMiodrag Dinic #include <linux/serial_core.h>
21666b7793SArve Hjønnevåg 
222296eee7SAleksandar Markovic /* Goldfish tty register's offsets */
232296eee7SAleksandar Markovic #define	GOLDFISH_TTY_REG_BYTES_READY	0x04
242296eee7SAleksandar Markovic #define	GOLDFISH_TTY_REG_CMD		0x08
252296eee7SAleksandar Markovic #define	GOLDFISH_TTY_REG_DATA_PTR	0x10
262296eee7SAleksandar Markovic #define	GOLDFISH_TTY_REG_DATA_LEN	0x14
272296eee7SAleksandar Markovic #define	GOLDFISH_TTY_REG_DATA_PTR_HIGH	0x18
287157d2beSMiodrag Dinic #define	GOLDFISH_TTY_REG_VERSION	0x20
29666b7793SArve Hjønnevåg 
302296eee7SAleksandar Markovic /* Goldfish tty commands */
312296eee7SAleksandar Markovic #define	GOLDFISH_TTY_CMD_INT_DISABLE	0
322296eee7SAleksandar Markovic #define	GOLDFISH_TTY_CMD_INT_ENABLE	1
332296eee7SAleksandar Markovic #define	GOLDFISH_TTY_CMD_WRITE_BUFFER	2
342296eee7SAleksandar Markovic #define	GOLDFISH_TTY_CMD_READ_BUFFER	3
35666b7793SArve Hjønnevåg 
36666b7793SArve Hjønnevåg struct goldfish_tty {
37666b7793SArve Hjønnevåg 	struct tty_port port;
38666b7793SArve Hjønnevåg 	spinlock_t lock;
39666b7793SArve Hjønnevåg 	void __iomem *base;
40666b7793SArve Hjønnevåg 	u32 irq;
41666b7793SArve Hjønnevåg 	int opencount;
42666b7793SArve Hjønnevåg 	struct console console;
437157d2beSMiodrag Dinic 	u32 version;
447157d2beSMiodrag Dinic 	struct device *dev;
45666b7793SArve Hjønnevåg };
46666b7793SArve Hjønnevåg 
47666b7793SArve Hjønnevåg static DEFINE_MUTEX(goldfish_tty_lock);
48666b7793SArve Hjønnevåg static struct tty_driver *goldfish_tty_driver;
49666b7793SArve Hjønnevåg static u32 goldfish_tty_line_count = 8;
50666b7793SArve Hjønnevåg static u32 goldfish_tty_current_line_count;
51666b7793SArve Hjønnevåg static struct goldfish_tty *goldfish_ttys;
52666b7793SArve Hjønnevåg 
537157d2beSMiodrag Dinic static void do_rw_io(struct goldfish_tty *qtty,
547157d2beSMiodrag Dinic 		     unsigned long address,
557157d2beSMiodrag Dinic 		     unsigned int count,
567157d2beSMiodrag Dinic 		     int is_write)
57666b7793SArve Hjønnevåg {
58666b7793SArve Hjønnevåg 	unsigned long irq_flags;
59666b7793SArve Hjønnevåg 	void __iomem *base = qtty->base;
607157d2beSMiodrag Dinic 
61666b7793SArve Hjønnevåg 	spin_lock_irqsave(&qtty->lock, irq_flags);
627157d2beSMiodrag Dinic 	gf_write_ptr((void *)address, base + GOLDFISH_TTY_REG_DATA_PTR,
632296eee7SAleksandar Markovic 		     base + GOLDFISH_TTY_REG_DATA_PTR_HIGH);
642296eee7SAleksandar Markovic 	writel(count, base + GOLDFISH_TTY_REG_DATA_LEN);
657157d2beSMiodrag Dinic 
667157d2beSMiodrag Dinic 	if (is_write)
677157d2beSMiodrag Dinic 		writel(GOLDFISH_TTY_CMD_WRITE_BUFFER,
687157d2beSMiodrag Dinic 		       base + GOLDFISH_TTY_REG_CMD);
697157d2beSMiodrag Dinic 	else
707157d2beSMiodrag Dinic 		writel(GOLDFISH_TTY_CMD_READ_BUFFER,
717157d2beSMiodrag Dinic 		       base + GOLDFISH_TTY_REG_CMD);
727157d2beSMiodrag Dinic 
73666b7793SArve Hjønnevåg 	spin_unlock_irqrestore(&qtty->lock, irq_flags);
74666b7793SArve Hjønnevåg }
75666b7793SArve Hjønnevåg 
767157d2beSMiodrag Dinic static void goldfish_tty_rw(struct goldfish_tty *qtty,
777157d2beSMiodrag Dinic 			    unsigned long addr,
787157d2beSMiodrag Dinic 			    unsigned int count,
797157d2beSMiodrag Dinic 			    int is_write)
807157d2beSMiodrag Dinic {
817157d2beSMiodrag Dinic 	dma_addr_t dma_handle;
827157d2beSMiodrag Dinic 	enum dma_data_direction dma_dir;
837157d2beSMiodrag Dinic 
847157d2beSMiodrag Dinic 	dma_dir = (is_write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
857157d2beSMiodrag Dinic 	if (qtty->version > 0) {
867157d2beSMiodrag Dinic 		/*
877157d2beSMiodrag Dinic 		 * Goldfish TTY for Ranchu platform uses
887157d2beSMiodrag Dinic 		 * physical addresses and DMA for read/write operations
897157d2beSMiodrag Dinic 		 */
907157d2beSMiodrag Dinic 		unsigned long addr_end = addr + count;
917157d2beSMiodrag Dinic 
927157d2beSMiodrag Dinic 		while (addr < addr_end) {
937157d2beSMiodrag Dinic 			unsigned long pg_end = (addr & PAGE_MASK) + PAGE_SIZE;
947157d2beSMiodrag Dinic 			unsigned long next =
957157d2beSMiodrag Dinic 					pg_end < addr_end ? pg_end : addr_end;
967157d2beSMiodrag Dinic 			unsigned long avail = next - addr;
977157d2beSMiodrag Dinic 
987157d2beSMiodrag Dinic 			/*
997157d2beSMiodrag Dinic 			 * Map the buffer's virtual address to the DMA address
1007157d2beSMiodrag Dinic 			 * so the buffer can be accessed by the device.
1017157d2beSMiodrag Dinic 			 */
1027157d2beSMiodrag Dinic 			dma_handle = dma_map_single(qtty->dev, (void *)addr,
1037157d2beSMiodrag Dinic 						    avail, dma_dir);
1047157d2beSMiodrag Dinic 
1057157d2beSMiodrag Dinic 			if (dma_mapping_error(qtty->dev, dma_handle)) {
1067157d2beSMiodrag Dinic 				dev_err(qtty->dev, "tty: DMA mapping error.\n");
1077157d2beSMiodrag Dinic 				return;
1087157d2beSMiodrag Dinic 			}
1097157d2beSMiodrag Dinic 			do_rw_io(qtty, dma_handle, avail, is_write);
1107157d2beSMiodrag Dinic 
1117157d2beSMiodrag Dinic 			/*
1127157d2beSMiodrag Dinic 			 * Unmap the previously mapped region after
1137157d2beSMiodrag Dinic 			 * the completion of the read/write operation.
1147157d2beSMiodrag Dinic 			 */
1157157d2beSMiodrag Dinic 			dma_unmap_single(qtty->dev, dma_handle, avail, dma_dir);
1167157d2beSMiodrag Dinic 
1177157d2beSMiodrag Dinic 			addr += avail;
1187157d2beSMiodrag Dinic 		}
1197157d2beSMiodrag Dinic 	} else {
1207157d2beSMiodrag Dinic 		/*
1217157d2beSMiodrag Dinic 		 * Old style Goldfish TTY used on the Goldfish platform
1227157d2beSMiodrag Dinic 		 * uses virtual addresses.
1237157d2beSMiodrag Dinic 		 */
1247157d2beSMiodrag Dinic 		do_rw_io(qtty, addr, count, is_write);
1257157d2beSMiodrag Dinic 	}
1267157d2beSMiodrag Dinic }
1277157d2beSMiodrag Dinic 
1287157d2beSMiodrag Dinic static void goldfish_tty_do_write(int line, const char *buf,
1297157d2beSMiodrag Dinic 				  unsigned int count)
1307157d2beSMiodrag Dinic {
1317157d2beSMiodrag Dinic 	struct goldfish_tty *qtty = &goldfish_ttys[line];
1327157d2beSMiodrag Dinic 	unsigned long address = (unsigned long)(void *)buf;
1337157d2beSMiodrag Dinic 
1347157d2beSMiodrag Dinic 	goldfish_tty_rw(qtty, address, count, 1);
1357157d2beSMiodrag Dinic }
1367157d2beSMiodrag Dinic 
137666b7793SArve Hjønnevåg static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
138666b7793SArve Hjønnevåg {
139465893e1SGreg Hackmann 	struct goldfish_tty *qtty = dev_id;
140666b7793SArve Hjønnevåg 	void __iomem *base = qtty->base;
1417157d2beSMiodrag Dinic 	unsigned long address;
142666b7793SArve Hjønnevåg 	unsigned char *buf;
143666b7793SArve Hjønnevåg 	u32 count;
144666b7793SArve Hjønnevåg 
1452296eee7SAleksandar Markovic 	count = readl(base + GOLDFISH_TTY_REG_BYTES_READY);
146666b7793SArve Hjønnevåg 	if (count == 0)
147666b7793SArve Hjønnevåg 		return IRQ_NONE;
148666b7793SArve Hjønnevåg 
149ebcf0981SAlan Cox 	count = tty_prepare_flip_string(&qtty->port, &buf, count);
1507157d2beSMiodrag Dinic 
1517157d2beSMiodrag Dinic 	address = (unsigned long)(void *)buf;
1527157d2beSMiodrag Dinic 	goldfish_tty_rw(qtty, address, count, 0);
1537157d2beSMiodrag Dinic 
154ebcf0981SAlan Cox 	tty_schedule_flip(&qtty->port);
155666b7793SArve Hjønnevåg 	return IRQ_HANDLED;
156666b7793SArve Hjønnevåg }
157666b7793SArve Hjønnevåg 
158666b7793SArve Hjønnevåg static int goldfish_tty_activate(struct tty_port *port, struct tty_struct *tty)
159666b7793SArve Hjønnevåg {
160d78055dcSAlan 	struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
161d78055dcSAlan 									port);
1622296eee7SAleksandar Markovic 	writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_REG_CMD);
163666b7793SArve Hjønnevåg 	return 0;
164666b7793SArve Hjønnevåg }
165666b7793SArve Hjønnevåg 
166666b7793SArve Hjønnevåg static void goldfish_tty_shutdown(struct tty_port *port)
167666b7793SArve Hjønnevåg {
168d78055dcSAlan 	struct goldfish_tty *qtty = container_of(port, struct goldfish_tty,
169d78055dcSAlan 									port);
1702296eee7SAleksandar Markovic 	writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_REG_CMD);
171666b7793SArve Hjønnevåg }
172666b7793SArve Hjønnevåg 
173666b7793SArve Hjønnevåg static int goldfish_tty_open(struct tty_struct *tty, struct file *filp)
174666b7793SArve Hjønnevåg {
175666b7793SArve Hjønnevåg 	struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
176666b7793SArve Hjønnevåg 	return tty_port_open(&qtty->port, tty, filp);
177666b7793SArve Hjønnevåg }
178666b7793SArve Hjønnevåg 
179666b7793SArve Hjønnevåg static void goldfish_tty_close(struct tty_struct *tty, struct file *filp)
180666b7793SArve Hjønnevåg {
181666b7793SArve Hjønnevåg 	tty_port_close(tty->port, tty, filp);
182666b7793SArve Hjønnevåg }
183666b7793SArve Hjønnevåg 
184666b7793SArve Hjønnevåg static void goldfish_tty_hangup(struct tty_struct *tty)
185666b7793SArve Hjønnevåg {
186666b7793SArve Hjønnevåg 	tty_port_hangup(tty->port);
187666b7793SArve Hjønnevåg }
188666b7793SArve Hjønnevåg 
189d78055dcSAlan static int goldfish_tty_write(struct tty_struct *tty, const unsigned char *buf,
190d78055dcSAlan 								int count)
191666b7793SArve Hjønnevåg {
192666b7793SArve Hjønnevåg 	goldfish_tty_do_write(tty->index, buf, count);
193666b7793SArve Hjønnevåg 	return count;
194666b7793SArve Hjønnevåg }
195666b7793SArve Hjønnevåg 
196666b7793SArve Hjønnevåg static int goldfish_tty_write_room(struct tty_struct *tty)
197666b7793SArve Hjønnevåg {
198666b7793SArve Hjønnevåg 	return 0x10000;
199666b7793SArve Hjønnevåg }
200666b7793SArve Hjønnevåg 
201666b7793SArve Hjønnevåg static int goldfish_tty_chars_in_buffer(struct tty_struct *tty)
202666b7793SArve Hjønnevåg {
203666b7793SArve Hjønnevåg 	struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
204666b7793SArve Hjønnevåg 	void __iomem *base = qtty->base;
2052296eee7SAleksandar Markovic 	return readl(base + GOLDFISH_TTY_REG_BYTES_READY);
206666b7793SArve Hjønnevåg }
207666b7793SArve Hjønnevåg 
208d78055dcSAlan static void goldfish_tty_console_write(struct console *co, const char *b,
209d78055dcSAlan 								unsigned count)
210666b7793SArve Hjønnevåg {
211666b7793SArve Hjønnevåg 	goldfish_tty_do_write(co->index, b, count);
212666b7793SArve Hjønnevåg }
213666b7793SArve Hjønnevåg 
214d78055dcSAlan static struct tty_driver *goldfish_tty_console_device(struct console *c,
215d78055dcSAlan 								int *index)
216666b7793SArve Hjønnevåg {
217666b7793SArve Hjønnevåg 	*index = c->index;
218666b7793SArve Hjønnevåg 	return goldfish_tty_driver;
219666b7793SArve Hjønnevåg }
220666b7793SArve Hjønnevåg 
221666b7793SArve Hjønnevåg static int goldfish_tty_console_setup(struct console *co, char *options)
222666b7793SArve Hjønnevåg {
223fda2b418SDan Carpenter 	if ((unsigned)co->index >= goldfish_tty_line_count)
224666b7793SArve Hjønnevåg 		return -ENODEV;
225a4dc9236SFabian Frederick 	if (!goldfish_ttys[co->index].base)
226666b7793SArve Hjønnevåg 		return -ENODEV;
227666b7793SArve Hjønnevåg 	return 0;
228666b7793SArve Hjønnevåg }
229666b7793SArve Hjønnevåg 
23004b757dfSAya Mahfouz static const struct tty_port_operations goldfish_port_ops = {
231666b7793SArve Hjønnevåg 	.activate = goldfish_tty_activate,
232666b7793SArve Hjønnevåg 	.shutdown = goldfish_tty_shutdown
233666b7793SArve Hjønnevåg };
234666b7793SArve Hjønnevåg 
235d78055dcSAlan static const struct tty_operations goldfish_tty_ops = {
236666b7793SArve Hjønnevåg 	.open = goldfish_tty_open,
237666b7793SArve Hjønnevåg 	.close = goldfish_tty_close,
238666b7793SArve Hjønnevåg 	.hangup = goldfish_tty_hangup,
239666b7793SArve Hjønnevåg 	.write = goldfish_tty_write,
240666b7793SArve Hjønnevåg 	.write_room = goldfish_tty_write_room,
241666b7793SArve Hjønnevåg 	.chars_in_buffer = goldfish_tty_chars_in_buffer,
242666b7793SArve Hjønnevåg };
243666b7793SArve Hjønnevåg 
244666b7793SArve Hjønnevåg static int goldfish_tty_create_driver(void)
245666b7793SArve Hjønnevåg {
246666b7793SArve Hjønnevåg 	int ret;
247666b7793SArve Hjønnevåg 	struct tty_driver *tty;
248666b7793SArve Hjønnevåg 
2496396bb22SKees Cook 	goldfish_ttys = kcalloc(goldfish_tty_line_count,
2506396bb22SKees Cook 				sizeof(*goldfish_ttys),
2516396bb22SKees Cook 				GFP_KERNEL);
252666b7793SArve Hjønnevåg 	if (goldfish_ttys == NULL) {
253666b7793SArve Hjønnevåg 		ret = -ENOMEM;
254666b7793SArve Hjønnevåg 		goto err_alloc_goldfish_ttys_failed;
255666b7793SArve Hjønnevåg 	}
256666b7793SArve Hjønnevåg 	tty = alloc_tty_driver(goldfish_tty_line_count);
257666b7793SArve Hjønnevåg 	if (tty == NULL) {
258666b7793SArve Hjønnevåg 		ret = -ENOMEM;
259666b7793SArve Hjønnevåg 		goto err_alloc_tty_driver_failed;
260666b7793SArve Hjønnevåg 	}
261666b7793SArve Hjønnevåg 	tty->driver_name = "goldfish";
262666b7793SArve Hjønnevåg 	tty->name = "ttyGF";
263666b7793SArve Hjønnevåg 	tty->type = TTY_DRIVER_TYPE_SERIAL;
264666b7793SArve Hjønnevåg 	tty->subtype = SERIAL_TYPE_NORMAL;
265666b7793SArve Hjønnevåg 	tty->init_termios = tty_std_termios;
266d78055dcSAlan 	tty->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
267d78055dcSAlan 						TTY_DRIVER_DYNAMIC_DEV;
268666b7793SArve Hjønnevåg 	tty_set_operations(tty, &goldfish_tty_ops);
269666b7793SArve Hjønnevåg 	ret = tty_register_driver(tty);
270666b7793SArve Hjønnevåg 	if (ret)
271666b7793SArve Hjønnevåg 		goto err_tty_register_driver_failed;
272666b7793SArve Hjønnevåg 
273666b7793SArve Hjønnevåg 	goldfish_tty_driver = tty;
274666b7793SArve Hjønnevåg 	return 0;
275666b7793SArve Hjønnevåg 
276666b7793SArve Hjønnevåg err_tty_register_driver_failed:
277666b7793SArve Hjønnevåg 	put_tty_driver(tty);
278666b7793SArve Hjønnevåg err_alloc_tty_driver_failed:
279666b7793SArve Hjønnevåg 	kfree(goldfish_ttys);
280666b7793SArve Hjønnevåg 	goldfish_ttys = NULL;
281666b7793SArve Hjønnevåg err_alloc_goldfish_ttys_failed:
282666b7793SArve Hjønnevåg 	return ret;
283666b7793SArve Hjønnevåg }
284666b7793SArve Hjønnevåg 
285666b7793SArve Hjønnevåg static void goldfish_tty_delete_driver(void)
286666b7793SArve Hjønnevåg {
287666b7793SArve Hjønnevåg 	tty_unregister_driver(goldfish_tty_driver);
288666b7793SArve Hjønnevåg 	put_tty_driver(goldfish_tty_driver);
289666b7793SArve Hjønnevåg 	goldfish_tty_driver = NULL;
290666b7793SArve Hjønnevåg 	kfree(goldfish_ttys);
291666b7793SArve Hjønnevåg 	goldfish_ttys = NULL;
292666b7793SArve Hjønnevåg }
293666b7793SArve Hjønnevåg 
294666b7793SArve Hjønnevåg static int goldfish_tty_probe(struct platform_device *pdev)
295666b7793SArve Hjønnevåg {
296666b7793SArve Hjønnevåg 	struct goldfish_tty *qtty;
2977157d2beSMiodrag Dinic 	int ret = -ENODEV;
298666b7793SArve Hjønnevåg 	struct resource *r;
299666b7793SArve Hjønnevåg 	struct device *ttydev;
300666b7793SArve Hjønnevåg 	void __iomem *base;
301666b7793SArve Hjønnevåg 	u32 irq;
302465893e1SGreg Hackmann 	unsigned int line;
303666b7793SArve Hjønnevåg 
304666b7793SArve Hjønnevåg 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
3057157d2beSMiodrag Dinic 	if (!r) {
3067157d2beSMiodrag Dinic 		pr_err("goldfish_tty: No MEM resource available!\n");
3077157d2beSMiodrag Dinic 		return -ENOMEM;
3087157d2beSMiodrag Dinic 	}
309666b7793SArve Hjønnevåg 
310666b7793SArve Hjønnevåg 	base = ioremap(r->start, 0x1000);
3117157d2beSMiodrag Dinic 	if (!base) {
3127157d2beSMiodrag Dinic 		pr_err("goldfish_tty: Unable to ioremap base!\n");
3137157d2beSMiodrag Dinic 		return -ENOMEM;
3147157d2beSMiodrag Dinic 	}
315666b7793SArve Hjønnevåg 
316666b7793SArve Hjønnevåg 	r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
3177157d2beSMiodrag Dinic 	if (!r) {
3187157d2beSMiodrag Dinic 		pr_err("goldfish_tty: No IRQ resource available!\n");
319666b7793SArve Hjønnevåg 		goto err_unmap;
3207157d2beSMiodrag Dinic 	}
321666b7793SArve Hjønnevåg 
322666b7793SArve Hjønnevåg 	irq = r->start;
323666b7793SArve Hjønnevåg 
324666b7793SArve Hjønnevåg 	mutex_lock(&goldfish_tty_lock);
325465893e1SGreg Hackmann 
326465893e1SGreg Hackmann 	if (pdev->id == PLATFORM_DEVID_NONE)
327465893e1SGreg Hackmann 		line = goldfish_tty_current_line_count;
328465893e1SGreg Hackmann 	else
329465893e1SGreg Hackmann 		line = pdev->id;
330465893e1SGreg Hackmann 
3317157d2beSMiodrag Dinic 	if (line >= goldfish_tty_line_count) {
3327157d2beSMiodrag Dinic 		pr_err("goldfish_tty: Reached maximum tty number of %d.\n",
3337157d2beSMiodrag Dinic 		       goldfish_tty_current_line_count);
3347157d2beSMiodrag Dinic 		ret = -ENOMEM;
3357157d2beSMiodrag Dinic 		goto err_unlock;
3367157d2beSMiodrag Dinic 	}
337465893e1SGreg Hackmann 
338666b7793SArve Hjønnevåg 	if (goldfish_tty_current_line_count == 0) {
339666b7793SArve Hjønnevåg 		ret = goldfish_tty_create_driver();
340666b7793SArve Hjønnevåg 		if (ret)
3417157d2beSMiodrag Dinic 			goto err_unlock;
342666b7793SArve Hjønnevåg 	}
343666b7793SArve Hjønnevåg 	goldfish_tty_current_line_count++;
344666b7793SArve Hjønnevåg 
345465893e1SGreg Hackmann 	qtty = &goldfish_ttys[line];
346666b7793SArve Hjønnevåg 	spin_lock_init(&qtty->lock);
347666b7793SArve Hjønnevåg 	tty_port_init(&qtty->port);
348666b7793SArve Hjønnevåg 	qtty->port.ops = &goldfish_port_ops;
349666b7793SArve Hjønnevåg 	qtty->base = base;
350666b7793SArve Hjønnevåg 	qtty->irq = irq;
3517157d2beSMiodrag Dinic 	qtty->dev = &pdev->dev;
3527157d2beSMiodrag Dinic 
3537157d2beSMiodrag Dinic 	/*
3547157d2beSMiodrag Dinic 	 * Goldfish TTY device used by the Goldfish emulator
3557157d2beSMiodrag Dinic 	 * should identify itself with 0, forcing the driver
3567157d2beSMiodrag Dinic 	 * to use virtual addresses. Goldfish TTY device
3577157d2beSMiodrag Dinic 	 * on Ranchu emulator (qemu2) returns 1 here and
3587157d2beSMiodrag Dinic 	 * driver will use physical addresses.
3597157d2beSMiodrag Dinic 	 */
3607157d2beSMiodrag Dinic 	qtty->version = readl(base + GOLDFISH_TTY_REG_VERSION);
3617157d2beSMiodrag Dinic 
3627157d2beSMiodrag Dinic 	/*
3637157d2beSMiodrag Dinic 	 * Goldfish TTY device on Ranchu emulator (qemu2)
3647157d2beSMiodrag Dinic 	 * will use DMA for read/write IO operations.
3657157d2beSMiodrag Dinic 	 */
3667157d2beSMiodrag Dinic 	if (qtty->version > 0) {
3677157d2beSMiodrag Dinic 		/*
3687157d2beSMiodrag Dinic 		 * Initialize dma_mask to 32-bits.
3697157d2beSMiodrag Dinic 		 */
3707157d2beSMiodrag Dinic 		if (!pdev->dev.dma_mask)
3717157d2beSMiodrag Dinic 			pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
3727157d2beSMiodrag Dinic 		ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
3737157d2beSMiodrag Dinic 		if (ret) {
3747157d2beSMiodrag Dinic 			dev_err(&pdev->dev, "No suitable DMA available.\n");
3757157d2beSMiodrag Dinic 			goto err_dec_line_count;
3767157d2beSMiodrag Dinic 		}
3777157d2beSMiodrag Dinic 	}
378666b7793SArve Hjønnevåg 
3792296eee7SAleksandar Markovic 	writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_REG_CMD);
380666b7793SArve Hjønnevåg 
381d78055dcSAlan 	ret = request_irq(irq, goldfish_tty_interrupt, IRQF_SHARED,
382465893e1SGreg Hackmann 			  "goldfish_tty", qtty);
3837157d2beSMiodrag Dinic 	if (ret) {
3847157d2beSMiodrag Dinic 		pr_err("goldfish_tty: No IRQ available!\n");
3857157d2beSMiodrag Dinic 		goto err_dec_line_count;
3867157d2beSMiodrag Dinic 	}
387666b7793SArve Hjønnevåg 
388666b7793SArve Hjønnevåg 	ttydev = tty_port_register_device(&qtty->port, goldfish_tty_driver,
389465893e1SGreg Hackmann 					  line, &pdev->dev);
390666b7793SArve Hjønnevåg 	if (IS_ERR(ttydev)) {
391666b7793SArve Hjønnevåg 		ret = PTR_ERR(ttydev);
392666b7793SArve Hjønnevåg 		goto err_tty_register_device_failed;
393666b7793SArve Hjønnevåg 	}
394666b7793SArve Hjønnevåg 
395666b7793SArve Hjønnevåg 	strcpy(qtty->console.name, "ttyGF");
396666b7793SArve Hjønnevåg 	qtty->console.write = goldfish_tty_console_write;
397666b7793SArve Hjønnevåg 	qtty->console.device = goldfish_tty_console_device;
398666b7793SArve Hjønnevåg 	qtty->console.setup = goldfish_tty_console_setup;
399666b7793SArve Hjønnevåg 	qtty->console.flags = CON_PRINTBUFFER;
400465893e1SGreg Hackmann 	qtty->console.index = line;
401666b7793SArve Hjønnevåg 	register_console(&qtty->console);
402465893e1SGreg Hackmann 	platform_set_drvdata(pdev, qtty);
403666b7793SArve Hjønnevåg 
404666b7793SArve Hjønnevåg 	mutex_unlock(&goldfish_tty_lock);
405666b7793SArve Hjønnevåg 	return 0;
406666b7793SArve Hjønnevåg 
407666b7793SArve Hjønnevåg err_tty_register_device_failed:
4081a5c2d1dSChristophe JAILLET 	free_irq(irq, qtty);
4097157d2beSMiodrag Dinic err_dec_line_count:
410666b7793SArve Hjønnevåg 	goldfish_tty_current_line_count--;
411666b7793SArve Hjønnevåg 	if (goldfish_tty_current_line_count == 0)
412666b7793SArve Hjønnevåg 		goldfish_tty_delete_driver();
4137157d2beSMiodrag Dinic err_unlock:
414666b7793SArve Hjønnevåg 	mutex_unlock(&goldfish_tty_lock);
415666b7793SArve Hjønnevåg err_unmap:
416666b7793SArve Hjønnevåg 	iounmap(base);
417666b7793SArve Hjønnevåg 	return ret;
418666b7793SArve Hjønnevåg }
419666b7793SArve Hjønnevåg 
420666b7793SArve Hjønnevåg static int goldfish_tty_remove(struct platform_device *pdev)
421666b7793SArve Hjønnevåg {
422465893e1SGreg Hackmann 	struct goldfish_tty *qtty = platform_get_drvdata(pdev);
423666b7793SArve Hjønnevåg 
424666b7793SArve Hjønnevåg 	mutex_lock(&goldfish_tty_lock);
425666b7793SArve Hjønnevåg 
426666b7793SArve Hjønnevåg 	unregister_console(&qtty->console);
427465893e1SGreg Hackmann 	tty_unregister_device(goldfish_tty_driver, qtty->console.index);
428666b7793SArve Hjønnevåg 	iounmap(qtty->base);
429a4dc9236SFabian Frederick 	qtty->base = NULL;
430666b7793SArve Hjønnevåg 	free_irq(qtty->irq, pdev);
431666b7793SArve Hjønnevåg 	goldfish_tty_current_line_count--;
432666b7793SArve Hjønnevåg 	if (goldfish_tty_current_line_count == 0)
433666b7793SArve Hjønnevåg 		goldfish_tty_delete_driver();
434666b7793SArve Hjønnevåg 	mutex_unlock(&goldfish_tty_lock);
435666b7793SArve Hjønnevåg 	return 0;
436666b7793SArve Hjønnevåg }
437666b7793SArve Hjønnevåg 
4386a28fd2bSSebastian Andrzej Siewior #ifdef CONFIG_GOLDFISH_TTY_EARLY_CONSOLE
4393840ed95SMiodrag Dinic static void gf_early_console_putchar(struct uart_port *port, int ch)
4403840ed95SMiodrag Dinic {
4413840ed95SMiodrag Dinic 	__raw_writel(ch, port->membase);
4423840ed95SMiodrag Dinic }
4433840ed95SMiodrag Dinic 
4443840ed95SMiodrag Dinic static void gf_early_write(struct console *con, const char *s, unsigned int n)
4453840ed95SMiodrag Dinic {
4463840ed95SMiodrag Dinic 	struct earlycon_device *dev = con->data;
4473840ed95SMiodrag Dinic 
4483840ed95SMiodrag Dinic 	uart_console_write(&dev->port, s, n, gf_early_console_putchar);
4493840ed95SMiodrag Dinic }
4503840ed95SMiodrag Dinic 
4513840ed95SMiodrag Dinic static int __init gf_earlycon_setup(struct earlycon_device *device,
4523840ed95SMiodrag Dinic 				    const char *opt)
4533840ed95SMiodrag Dinic {
4543840ed95SMiodrag Dinic 	if (!device->port.membase)
4553840ed95SMiodrag Dinic 		return -ENODEV;
4563840ed95SMiodrag Dinic 
4573840ed95SMiodrag Dinic 	device->con->write = gf_early_write;
4583840ed95SMiodrag Dinic 	return 0;
4593840ed95SMiodrag Dinic }
4603840ed95SMiodrag Dinic 
4613840ed95SMiodrag Dinic OF_EARLYCON_DECLARE(early_gf_tty, "google,goldfish-tty", gf_earlycon_setup);
4626a28fd2bSSebastian Andrzej Siewior #endif
4633840ed95SMiodrag Dinic 
4649b883eeaSMiodrag Dinic static const struct of_device_id goldfish_tty_of_match[] = {
4659b883eeaSMiodrag Dinic 	{ .compatible = "google,goldfish-tty", },
4669b883eeaSMiodrag Dinic 	{},
4679b883eeaSMiodrag Dinic };
4689b883eeaSMiodrag Dinic 
4699b883eeaSMiodrag Dinic MODULE_DEVICE_TABLE(of, goldfish_tty_of_match);
4709b883eeaSMiodrag Dinic 
471666b7793SArve Hjønnevåg static struct platform_driver goldfish_tty_platform_driver = {
472666b7793SArve Hjønnevåg 	.probe = goldfish_tty_probe,
473666b7793SArve Hjønnevåg 	.remove = goldfish_tty_remove,
474666b7793SArve Hjønnevåg 	.driver = {
4759b883eeaSMiodrag Dinic 		.name = "goldfish_tty",
4769b883eeaSMiodrag Dinic 		.of_match_table = goldfish_tty_of_match,
477666b7793SArve Hjønnevåg 	}
478666b7793SArve Hjønnevåg };
479666b7793SArve Hjønnevåg 
480666b7793SArve Hjønnevåg module_platform_driver(goldfish_tty_platform_driver);
481666b7793SArve Hjønnevåg 
482666b7793SArve Hjønnevåg MODULE_LICENSE("GPL v2");
483