1
2
3
4
5
6
7
8
9
10
11
12#include <linux/console.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/delay.h>
16#include <linux/serial_core.h>
17#include <linux/serial_reg.h>
18#include <linux/of_address.h>
19#include <linux/of_irq.h>
20#include <linux/of_platform.h>
21#include <linux/nwpserial.h>
22#include <linux/clk.h>
23
24#include "8250/8250.h"
25
26struct of_serial_info {
27 struct clk *clk;
28 int type;
29 int line;
30};
31
32#ifdef CONFIG_ARCH_TEGRA
33void tegra_serial_handle_break(struct uart_port *p)
34{
35 unsigned int status, tmout = 10000;
36
37 do {
38 status = p->serial_in(p, UART_LSR);
39 if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
40 status = p->serial_in(p, UART_RX);
41 else
42 break;
43 if (--tmout == 0)
44 break;
45 udelay(1);
46 } while (1);
47}
48#else
49static inline void tegra_serial_handle_break(struct uart_port *port)
50{
51}
52#endif
53
54
55
56
57static int of_platform_serial_setup(struct platform_device *ofdev,
58 int type, struct uart_port *port,
59 struct of_serial_info *info)
60{
61 struct resource resource;
62 struct device_node *np = ofdev->dev.of_node;
63 u32 clk, spd, prop;
64 int ret;
65
66 memset(port, 0, sizeof *port);
67 if (of_property_read_u32(np, "clock-frequency", &clk)) {
68
69
70 info->clk = clk_get(&ofdev->dev, NULL);
71 if (IS_ERR(info->clk)) {
72 dev_warn(&ofdev->dev,
73 "clk or clock-frequency not defined\n");
74 return PTR_ERR(info->clk);
75 }
76
77 clk_prepare_enable(info->clk);
78 clk = clk_get_rate(info->clk);
79 }
80
81 if (of_property_read_u32(np, "current-speed", &spd) == 0)
82 port->custom_divisor = clk / (16 * spd);
83
84 ret = of_address_to_resource(np, 0, &resource);
85 if (ret) {
86 dev_warn(&ofdev->dev, "invalid address\n");
87 goto out;
88 }
89
90 spin_lock_init(&port->lock);
91 port->mapbase = resource.start;
92
93
94 if (of_property_read_u32(np, "reg-offset", &prop) == 0)
95 port->mapbase += prop;
96
97
98 if (of_property_read_u32(np, "reg-shift", &prop) == 0)
99 port->regshift = prop;
100
101
102 if (of_property_read_u32(np, "fifo-size", &prop) == 0)
103 port->fifosize = prop;
104
105 port->irq = irq_of_parse_and_map(np, 0);
106 port->iotype = UPIO_MEM;
107 if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
108 switch (prop) {
109 case 1:
110 port->iotype = UPIO_MEM;
111 break;
112 case 4:
113 port->iotype = UPIO_MEM32;
114 break;
115 default:
116 dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
117 prop);
118 ret = -EINVAL;
119 goto out;
120 }
121 }
122
123 port->type = type;
124 port->uartclk = clk;
125 port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
126 | UPF_FIXED_PORT | UPF_FIXED_TYPE;
127
128 if (of_find_property(np, "no-loopback-test", NULL))
129 port->flags |= UPF_SKIP_TEST;
130
131 port->dev = &ofdev->dev;
132
133 switch (type) {
134 case PORT_TEGRA:
135 port->handle_break = tegra_serial_handle_break;
136 break;
137
138 case PORT_RT2880:
139 port->iotype = UPIO_AU;
140 break;
141 }
142
143 return 0;
144out:
145 if (info->clk)
146 clk_disable_unprepare(info->clk);
147 return ret;
148}
149
150
151
152
153static struct of_device_id of_platform_serial_table[];
154static int of_platform_serial_probe(struct platform_device *ofdev)
155{
156 const struct of_device_id *match;
157 struct of_serial_info *info;
158 struct uart_port port;
159 int port_type;
160 int ret;
161
162 match = of_match_device(of_platform_serial_table, &ofdev->dev);
163 if (!match)
164 return -EINVAL;
165
166 if (of_find_property(ofdev->dev.of_node, "used-by-rtas", NULL))
167 return -EBUSY;
168
169 info = kzalloc(sizeof(*info), GFP_KERNEL);
170 if (info == NULL)
171 return -ENOMEM;
172
173 port_type = (unsigned long)match->data;
174 ret = of_platform_serial_setup(ofdev, port_type, &port, info);
175 if (ret)
176 goto out;
177
178 switch (port_type) {
179#ifdef CONFIG_SERIAL_8250
180 case PORT_8250 ... PORT_MAX_8250:
181 {
182 struct uart_8250_port port8250;
183 memset(&port8250, 0, sizeof(port8250));
184 port.type = port_type;
185 port8250.port = port;
186
187 if (port.fifosize)
188 port8250.capabilities = UART_CAP_FIFO;
189
190 if (of_property_read_bool(ofdev->dev.of_node,
191 "auto-flow-control"))
192 port8250.capabilities |= UART_CAP_AFE;
193
194 ret = serial8250_register_8250_port(&port8250);
195 break;
196 }
197#endif
198#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
199 case PORT_NWPSERIAL:
200 ret = nwpserial_register_port(&port);
201 break;
202#endif
203 default:
204
205 case PORT_UNKNOWN:
206 dev_info(&ofdev->dev, "Unknown serial port found, ignored\n");
207 ret = -ENODEV;
208 break;
209 }
210 if (ret < 0)
211 goto out;
212
213 info->type = port_type;
214 info->line = ret;
215 platform_set_drvdata(ofdev, info);
216 return 0;
217out:
218 kfree(info);
219 irq_dispose_mapping(port.irq);
220 return ret;
221}
222
223
224
225
226static int of_platform_serial_remove(struct platform_device *ofdev)
227{
228 struct of_serial_info *info = platform_get_drvdata(ofdev);
229 switch (info->type) {
230#ifdef CONFIG_SERIAL_8250
231 case PORT_8250 ... PORT_MAX_8250:
232 serial8250_unregister_port(info->line);
233 break;
234#endif
235#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
236 case PORT_NWPSERIAL:
237 nwpserial_unregister_port(info->line);
238 break;
239#endif
240 default:
241
242 break;
243 }
244
245 if (info->clk)
246 clk_disable_unprepare(info->clk);
247 kfree(info);
248 return 0;
249}
250
251#ifdef CONFIG_PM_SLEEP
252#ifdef CONFIG_SERIAL_8250
253static void of_serial_suspend_8250(struct of_serial_info *info)
254{
255 struct uart_8250_port *port8250 = serial8250_get_port(info->line);
256 struct uart_port *port = &port8250->port;
257
258 serial8250_suspend_port(info->line);
259 if (info->clk && (!uart_console(port) || console_suspend_enabled))
260 clk_disable_unprepare(info->clk);
261}
262
263static void of_serial_resume_8250(struct of_serial_info *info)
264{
265 struct uart_8250_port *port8250 = serial8250_get_port(info->line);
266 struct uart_port *port = &port8250->port;
267
268 if (info->clk && (!uart_console(port) || console_suspend_enabled))
269 clk_prepare_enable(info->clk);
270
271 serial8250_resume_port(info->line);
272}
273#else
274static inline void of_serial_suspend_8250(struct of_serial_info *info)
275{
276}
277
278static inline void of_serial_resume_8250(struct of_serial_info *info)
279{
280}
281#endif
282
283static int of_serial_suspend(struct device *dev)
284{
285 struct of_serial_info *info = dev_get_drvdata(dev);
286
287 switch (info->type) {
288 case PORT_8250 ... PORT_MAX_8250:
289 of_serial_suspend_8250(info);
290 break;
291 default:
292 break;
293 }
294
295 return 0;
296}
297
298static int of_serial_resume(struct device *dev)
299{
300 struct of_serial_info *info = dev_get_drvdata(dev);
301
302 switch (info->type) {
303 case PORT_8250 ... PORT_MAX_8250:
304 of_serial_resume_8250(info);
305 break;
306 default:
307 break;
308 }
309
310 return 0;
311}
312#endif
313static SIMPLE_DEV_PM_OPS(of_serial_pm_ops, of_serial_suspend, of_serial_resume);
314
315
316
317
318static struct of_device_id of_platform_serial_table[] = {
319 { .compatible = "ns8250", .data = (void *)PORT_8250, },
320 { .compatible = "ns16450", .data = (void *)PORT_16450, },
321 { .compatible = "ns16550a", .data = (void *)PORT_16550A, },
322 { .compatible = "ns16550", .data = (void *)PORT_16550, },
323 { .compatible = "ns16750", .data = (void *)PORT_16750, },
324 { .compatible = "ns16850", .data = (void *)PORT_16850, },
325 { .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
326 { .compatible = "nxp,lpc3220-uart", .data = (void *)PORT_LPC3220, },
327 { .compatible = "ralink,rt2880-uart", .data = (void *)PORT_RT2880, },
328 { .compatible = "altr,16550-FIFO32",
329 .data = (void *)PORT_ALTR_16550_F32, },
330 { .compatible = "altr,16550-FIFO64",
331 .data = (void *)PORT_ALTR_16550_F64, },
332 { .compatible = "altr,16550-FIFO128",
333 .data = (void *)PORT_ALTR_16550_F128, },
334#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
335 { .compatible = "ibm,qpace-nwp-serial",
336 .data = (void *)PORT_NWPSERIAL, },
337#endif
338 { .type = "serial", .data = (void *)PORT_UNKNOWN, },
339 { },
340};
341
342static struct platform_driver of_platform_serial_driver = {
343 .driver = {
344 .name = "of_serial",
345 .of_match_table = of_platform_serial_table,
346 },
347 .probe = of_platform_serial_probe,
348 .remove = of_platform_serial_remove,
349};
350
351module_platform_driver(of_platform_serial_driver);
352
353MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
354MODULE_LICENSE("GPL");
355MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");
356
