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10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/init.h>
14#include <linux/serio.h>
15#include <linux/interrupt.h>
16#include <linux/delay.h>
17#include <linux/err.h>
18#include <linux/io.h>
19#include <linux/clk.h>
20#include <linux/platform_device.h>
21#include <linux/slab.h>
22
23
24#define PSIF_CR 0x00
25#define PSIF_RHR 0x04
26#define PSIF_THR 0x08
27#define PSIF_SR 0x10
28#define PSIF_IER 0x14
29#define PSIF_IDR 0x18
30#define PSIF_IMR 0x1c
31#define PSIF_PSR 0x24
32
33
34#define PSIF_CR_RXDIS_OFFSET 1
35#define PSIF_CR_RXDIS_SIZE 1
36#define PSIF_CR_RXEN_OFFSET 0
37#define PSIF_CR_RXEN_SIZE 1
38#define PSIF_CR_SWRST_OFFSET 15
39#define PSIF_CR_SWRST_SIZE 1
40#define PSIF_CR_TXDIS_OFFSET 9
41#define PSIF_CR_TXDIS_SIZE 1
42#define PSIF_CR_TXEN_OFFSET 8
43#define PSIF_CR_TXEN_SIZE 1
44
45
46#define PSIF_NACK_OFFSET 8
47#define PSIF_NACK_SIZE 1
48#define PSIF_OVRUN_OFFSET 5
49#define PSIF_OVRUN_SIZE 1
50#define PSIF_PARITY_OFFSET 9
51#define PSIF_PARITY_SIZE 1
52#define PSIF_RXRDY_OFFSET 4
53#define PSIF_RXRDY_SIZE 1
54#define PSIF_TXEMPTY_OFFSET 1
55#define PSIF_TXEMPTY_SIZE 1
56#define PSIF_TXRDY_OFFSET 0
57#define PSIF_TXRDY_SIZE 1
58
59
60#define PSIF_PSR_PRSCV_OFFSET 0
61#define PSIF_PSR_PRSCV_SIZE 12
62
63
64#define PSIF_RHR_RXDATA_OFFSET 0
65#define PSIF_RHR_RXDATA_SIZE 8
66
67
68#define PSIF_THR_TXDATA_OFFSET 0
69#define PSIF_THR_TXDATA_SIZE 8
70
71
72#define PSIF_BIT(name) \
73 (1 << PSIF_##name##_OFFSET)
74
75#define PSIF_BF(name, value) \
76 (((value) & ((1 << PSIF_##name##_SIZE) - 1)) \
77 << PSIF_##name##_OFFSET)
78
79#define PSIF_BFEXT(name, value) \
80 (((value) >> PSIF_##name##_OFFSET) \
81 & ((1 << PSIF_##name##_SIZE) - 1))
82
83#define PSIF_BFINS(name, value, old) \
84 (((old) & ~(((1 << PSIF_##name##_SIZE) - 1) \
85 << PSIF_##name##_OFFSET)) \
86 | PSIF_BF(name, value))
87
88
89#define psif_readl(port, reg) \
90 __raw_readl((port)->regs + PSIF_##reg)
91
92#define psif_writel(port, reg, value) \
93 __raw_writel((value), (port)->regs + PSIF_##reg)
94
95struct psif {
96 struct platform_device *pdev;
97 struct clk *pclk;
98 struct serio *io;
99 void __iomem *regs;
100 unsigned int irq;
101
102 spinlock_t lock;
103 bool open;
104};
105
106static irqreturn_t psif_interrupt(int irq, void *_ptr)
107{
108 struct psif *psif = _ptr;
109 int retval = IRQ_NONE;
110 unsigned int io_flags = 0;
111 unsigned long status;
112
113 status = psif_readl(psif, SR);
114
115 if (status & PSIF_BIT(RXRDY)) {
116 unsigned char val = (unsigned char) psif_readl(psif, RHR);
117
118 if (status & PSIF_BIT(PARITY))
119 io_flags |= SERIO_PARITY;
120 if (status & PSIF_BIT(OVRUN))
121 dev_err(&psif->pdev->dev, "overrun read error\n");
122
123 serio_interrupt(psif->io, val, io_flags);
124
125 retval = IRQ_HANDLED;
126 }
127
128 return retval;
129}
130
131static int psif_write(struct serio *io, unsigned char val)
132{
133 struct psif *psif = io->port_data;
134 unsigned long flags;
135 int timeout = 10;
136 int retval = 0;
137
138 spin_lock_irqsave(&psif->lock, flags);
139
140 while (!(psif_readl(psif, SR) & PSIF_BIT(TXEMPTY)) && timeout--)
141 udelay(50);
142
143 if (timeout >= 0) {
144 psif_writel(psif, THR, val);
145 } else {
146 dev_dbg(&psif->pdev->dev, "timeout writing to THR\n");
147 retval = -EBUSY;
148 }
149
150 spin_unlock_irqrestore(&psif->lock, flags);
151
152 return retval;
153}
154
155static int psif_open(struct serio *io)
156{
157 struct psif *psif = io->port_data;
158 int retval;
159
160 retval = clk_enable(psif->pclk);
161 if (retval)
162 goto out;
163
164 psif_writel(psif, CR, PSIF_BIT(CR_TXEN) | PSIF_BIT(CR_RXEN));
165 psif_writel(psif, IER, PSIF_BIT(RXRDY));
166
167 psif->open = true;
168out:
169 return retval;
170}
171
172static void psif_close(struct serio *io)
173{
174 struct psif *psif = io->port_data;
175
176 psif->open = false;
177
178 psif_writel(psif, IDR, ~0UL);
179 psif_writel(psif, CR, PSIF_BIT(CR_TXDIS) | PSIF_BIT(CR_RXDIS));
180
181 clk_disable(psif->pclk);
182}
183
184static void psif_set_prescaler(struct psif *psif)
185{
186 unsigned long prscv;
187 unsigned long rate = clk_get_rate(psif->pclk);
188
189
190 prscv = 100 * (rate / 1000000UL);
191
192 if (prscv > ((1<<PSIF_PSR_PRSCV_SIZE) - 1)) {
193 prscv = (1<<PSIF_PSR_PRSCV_SIZE) - 1;
194 dev_dbg(&psif->pdev->dev, "pclk too fast, "
195 "prescaler set to max\n");
196 }
197
198 clk_enable(psif->pclk);
199 psif_writel(psif, PSR, prscv);
200 clk_disable(psif->pclk);
201}
202
203static int __init psif_probe(struct platform_device *pdev)
204{
205 struct resource *regs;
206 struct psif *psif;
207 struct serio *io;
208 struct clk *pclk;
209 int irq;
210 int ret;
211
212 psif = kzalloc(sizeof(struct psif), GFP_KERNEL);
213 if (!psif) {
214 dev_dbg(&pdev->dev, "out of memory\n");
215 ret = -ENOMEM;
216 goto out;
217 }
218 psif->pdev = pdev;
219
220 io = kzalloc(sizeof(struct serio), GFP_KERNEL);
221 if (!io) {
222 dev_dbg(&pdev->dev, "out of memory\n");
223 ret = -ENOMEM;
224 goto out_free_psif;
225 }
226 psif->io = io;
227
228 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
229 if (!regs) {
230 dev_dbg(&pdev->dev, "no mmio resources defined\n");
231 ret = -ENOMEM;
232 goto out_free_io;
233 }
234
235 psif->regs = ioremap(regs->start, resource_size(regs));
236 if (!psif->regs) {
237 ret = -ENOMEM;
238 dev_dbg(&pdev->dev, "could not map I/O memory\n");
239 goto out_free_io;
240 }
241
242 pclk = clk_get(&pdev->dev, "pclk");
243 if (IS_ERR(pclk)) {
244 dev_dbg(&pdev->dev, "could not get peripheral clock\n");
245 ret = PTR_ERR(pclk);
246 goto out_iounmap;
247 }
248 psif->pclk = pclk;
249
250
251 ret = clk_enable(pclk);
252 if (ret) {
253 dev_dbg(&pdev->dev, "could not enable pclk\n");
254 goto out_put_clk;
255 }
256 psif_writel(psif, CR, PSIF_BIT(CR_SWRST));
257 clk_disable(pclk);
258
259 irq = platform_get_irq(pdev, 0);
260 if (irq < 0) {
261 dev_dbg(&pdev->dev, "could not get irq\n");
262 ret = -ENXIO;
263 goto out_put_clk;
264 }
265 ret = request_irq(irq, psif_interrupt, IRQF_SHARED, "at32psif", psif);
266 if (ret) {
267 dev_dbg(&pdev->dev, "could not request irq %d\n", irq);
268 goto out_put_clk;
269 }
270 psif->irq = irq;
271
272 io->id.type = SERIO_8042;
273 io->write = psif_write;
274 io->open = psif_open;
275 io->close = psif_close;
276 snprintf(io->name, sizeof(io->name), "AVR32 PS/2 port%d", pdev->id);
277 snprintf(io->phys, sizeof(io->phys), "at32psif/serio%d", pdev->id);
278 io->port_data = psif;
279 io->dev.parent = &pdev->dev;
280
281 psif_set_prescaler(psif);
282
283 spin_lock_init(&psif->lock);
284 serio_register_port(psif->io);
285 platform_set_drvdata(pdev, psif);
286
287 dev_info(&pdev->dev, "Atmel AVR32 PSIF PS/2 driver on 0x%08x irq %d\n",
288 (int)psif->regs, psif->irq);
289
290 return 0;
291
292out_put_clk:
293 clk_put(psif->pclk);
294out_iounmap:
295 iounmap(psif->regs);
296out_free_io:
297 kfree(io);
298out_free_psif:
299 kfree(psif);
300out:
301 return ret;
302}
303
304static int __exit psif_remove(struct platform_device *pdev)
305{
306 struct psif *psif = platform_get_drvdata(pdev);
307
308 psif_writel(psif, IDR, ~0UL);
309 psif_writel(psif, CR, PSIF_BIT(CR_TXDIS) | PSIF_BIT(CR_RXDIS));
310
311 serio_unregister_port(psif->io);
312 iounmap(psif->regs);
313 free_irq(psif->irq, psif);
314 clk_put(psif->pclk);
315 kfree(psif);
316
317 return 0;
318}
319
320#ifdef CONFIG_PM_SLEEP
321static int psif_suspend(struct device *dev)
322{
323 struct platform_device *pdev = to_platform_device(dev);
324 struct psif *psif = platform_get_drvdata(pdev);
325
326 if (psif->open) {
327 psif_writel(psif, CR, PSIF_BIT(CR_RXDIS) | PSIF_BIT(CR_TXDIS));
328 clk_disable(psif->pclk);
329 }
330
331 return 0;
332}
333
334static int psif_resume(struct device *dev)
335{
336 struct platform_device *pdev = to_platform_device(dev);
337 struct psif *psif = platform_get_drvdata(pdev);
338
339 if (psif->open) {
340 clk_enable(psif->pclk);
341 psif_set_prescaler(psif);
342 psif_writel(psif, CR, PSIF_BIT(CR_RXEN) | PSIF_BIT(CR_TXEN));
343 }
344
345 return 0;
346}
347#endif
348
349static SIMPLE_DEV_PM_OPS(psif_pm_ops, psif_suspend, psif_resume);
350
351static struct platform_driver psif_driver = {
352 .remove = __exit_p(psif_remove),
353 .driver = {
354 .name = "atmel_psif",
355 .pm = &psif_pm_ops,
356 },
357};
358
359module_platform_driver_probe(psif_driver, psif_probe);
360
361MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
362MODULE_DESCRIPTION("Atmel AVR32 PSIF PS/2 driver");
363MODULE_LICENSE("GPL");
364
