diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-04-07 11:45:12 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-04-07 11:45:12 -0400 |
commit | 0e26da0f2200a2fb51844aaa43e365ea9dd5a93d (patch) | |
tree | 73409a696901934da5f6df976c6521d3e50e8749 /drivers/i2c/busses/i2c-s6000.c | |
parent | 10a0d912898ac2fe49094acf2c1339d0fb4c2bc6 (diff) | |
parent | 65de394df21f8ccc61525f77b0e4ee6940a0932e (diff) |
Merge branch 'i2c-for-2630-v2' of git://aeryn.fluff.org.uk/bjdooks/linux
* 'i2c-for-2630-v2' of git://aeryn.fluff.org.uk/bjdooks/linux:
i2c: imx: Make disable_delay a per-device variable
i2c: xtensa s6000 i2c driver
powerpc/85xx: i2c-mpc: use new I2C bindings for the Socates board
i2c: i2c-mpc: make I2C bus speed configurable
i2c: i2c-mpc: use dev based printout function
i2c: i2c-mpc: various coding style fixes
i2c: imx: Add missing request_mem_region in probe()
i2c: i2c-s3c2410: Initialise Samsung I2C controller early
i2c-s3c2410: Simplify bus frequency calculation
i2c-s3c2410: sda_delay should be in ns, not clock ticks
i2c: iMX/MXC support
Diffstat (limited to 'drivers/i2c/busses/i2c-s6000.c')
-rw-r--r-- | drivers/i2c/busses/i2c-s6000.c | 407 |
1 files changed, 407 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-s6000.c b/drivers/i2c/busses/i2c-s6000.c new file mode 100644 index 000000000000..c91359f4965c --- /dev/null +++ b/drivers/i2c/busses/i2c-s6000.c | |||
@@ -0,0 +1,407 @@ | |||
1 | /* | ||
2 | * drivers/i2c/busses/i2c-s6000.c | ||
3 | * | ||
4 | * Description: Driver for S6000 Family I2C Interface | ||
5 | * Copyright (c) 2008 emlix GmbH | ||
6 | * Author: Oskar Schirmer <os@emlix.com> | ||
7 | * | ||
8 | * Partially based on i2c-bfin-twi.c driver by <sonic.zhang@analog.com> | ||
9 | * Copyright (c) 2005-2007 Analog Devices, Inc. | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or modify | ||
12 | * it under the terms of the GNU General Public License as published by | ||
13 | * the Free Software Foundation; either version 2 of the License, or | ||
14 | * (at your option) any later version. | ||
15 | * | ||
16 | * This program is distributed in the hope that it will be useful, | ||
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
19 | * GNU General Public License for more details. | ||
20 | * | ||
21 | * You should have received a copy of the GNU General Public License | ||
22 | * along with this program; if not, write to the Free Software | ||
23 | * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA | ||
24 | */ | ||
25 | |||
26 | #include <linux/clk.h> | ||
27 | #include <linux/err.h> | ||
28 | #include <linux/module.h> | ||
29 | #include <linux/kernel.h> | ||
30 | #include <linux/init.h> | ||
31 | #include <linux/delay.h> | ||
32 | #include <linux/i2c.h> | ||
33 | #include <linux/i2c/s6000.h> | ||
34 | #include <linux/timer.h> | ||
35 | #include <linux/spinlock.h> | ||
36 | #include <linux/completion.h> | ||
37 | #include <linux/interrupt.h> | ||
38 | #include <linux/platform_device.h> | ||
39 | |||
40 | #include <asm/io.h> | ||
41 | #include "i2c-s6000.h" | ||
42 | |||
43 | #define DRV_NAME "i2c-s6000" | ||
44 | |||
45 | #define POLL_TIMEOUT (2 * HZ) | ||
46 | |||
47 | struct s6i2c_if { | ||
48 | u8 __iomem *reg; /* memory mapped registers */ | ||
49 | int irq; | ||
50 | spinlock_t lock; | ||
51 | struct i2c_msg *msgs; /* messages currently handled */ | ||
52 | int msgs_num; /* nb of msgs to do */ | ||
53 | int msgs_push; /* nb of msgs read/written */ | ||
54 | int msgs_done; /* nb of msgs finally handled */ | ||
55 | unsigned push; /* nb of bytes read/written in msg */ | ||
56 | unsigned done; /* nb of bytes finally handled */ | ||
57 | int timeout_count; /* timeout retries left */ | ||
58 | struct timer_list timeout_timer; | ||
59 | struct i2c_adapter adap; | ||
60 | struct completion complete; | ||
61 | struct clk *clk; | ||
62 | struct resource *res; | ||
63 | }; | ||
64 | |||
65 | static inline u16 i2c_rd16(struct s6i2c_if *iface, unsigned n) | ||
66 | { | ||
67 | return readw(iface->reg + (n)); | ||
68 | } | ||
69 | |||
70 | static inline void i2c_wr16(struct s6i2c_if *iface, unsigned n, u16 v) | ||
71 | { | ||
72 | writew(v, iface->reg + (n)); | ||
73 | } | ||
74 | |||
75 | static inline u32 i2c_rd32(struct s6i2c_if *iface, unsigned n) | ||
76 | { | ||
77 | return readl(iface->reg + (n)); | ||
78 | } | ||
79 | |||
80 | static inline void i2c_wr32(struct s6i2c_if *iface, unsigned n, u32 v) | ||
81 | { | ||
82 | writel(v, iface->reg + (n)); | ||
83 | } | ||
84 | |||
85 | static struct s6i2c_if s6i2c_if; | ||
86 | |||
87 | static void s6i2c_handle_interrupt(struct s6i2c_if *iface) | ||
88 | { | ||
89 | if (i2c_rd16(iface, S6_I2C_INTRSTAT) & (1 << S6_I2C_INTR_TXABRT)) { | ||
90 | i2c_rd16(iface, S6_I2C_CLRTXABRT); | ||
91 | i2c_wr16(iface, S6_I2C_INTRMASK, 0); | ||
92 | complete(&iface->complete); | ||
93 | return; | ||
94 | } | ||
95 | if (iface->msgs_done >= iface->msgs_num) { | ||
96 | dev_err(&iface->adap.dev, "s6i2c: spurious I2C irq: %04x\n", | ||
97 | i2c_rd16(iface, S6_I2C_INTRSTAT)); | ||
98 | i2c_wr16(iface, S6_I2C_INTRMASK, 0); | ||
99 | return; | ||
100 | } | ||
101 | while ((iface->msgs_push < iface->msgs_num) | ||
102 | && (i2c_rd16(iface, S6_I2C_STATUS) & (1 << S6_I2C_STATUS_TFNF))) { | ||
103 | struct i2c_msg *m = &iface->msgs[iface->msgs_push]; | ||
104 | if (!(m->flags & I2C_M_RD)) | ||
105 | i2c_wr16(iface, S6_I2C_DATACMD, m->buf[iface->push]); | ||
106 | else | ||
107 | i2c_wr16(iface, S6_I2C_DATACMD, | ||
108 | 1 << S6_I2C_DATACMD_READ); | ||
109 | if (++iface->push >= m->len) { | ||
110 | iface->push = 0; | ||
111 | iface->msgs_push += 1; | ||
112 | } | ||
113 | } | ||
114 | do { | ||
115 | struct i2c_msg *m = &iface->msgs[iface->msgs_done]; | ||
116 | if (!(m->flags & I2C_M_RD)) { | ||
117 | if (iface->msgs_done < iface->msgs_push) | ||
118 | iface->msgs_done += 1; | ||
119 | else | ||
120 | break; | ||
121 | } else if (i2c_rd16(iface, S6_I2C_STATUS) | ||
122 | & (1 << S6_I2C_STATUS_RFNE)) { | ||
123 | m->buf[iface->done] = i2c_rd16(iface, S6_I2C_DATACMD); | ||
124 | if (++iface->done >= m->len) { | ||
125 | iface->done = 0; | ||
126 | iface->msgs_done += 1; | ||
127 | } | ||
128 | } else{ | ||
129 | break; | ||
130 | } | ||
131 | } while (iface->msgs_done < iface->msgs_num); | ||
132 | if (iface->msgs_done >= iface->msgs_num) { | ||
133 | i2c_wr16(iface, S6_I2C_INTRMASK, 1 << S6_I2C_INTR_TXABRT); | ||
134 | complete(&iface->complete); | ||
135 | } else if (iface->msgs_push >= iface->msgs_num) { | ||
136 | i2c_wr16(iface, S6_I2C_INTRMASK, (1 << S6_I2C_INTR_TXABRT) | | ||
137 | (1 << S6_I2C_INTR_RXFULL)); | ||
138 | } else { | ||
139 | i2c_wr16(iface, S6_I2C_INTRMASK, (1 << S6_I2C_INTR_TXABRT) | | ||
140 | (1 << S6_I2C_INTR_TXEMPTY) | | ||
141 | (1 << S6_I2C_INTR_RXFULL)); | ||
142 | } | ||
143 | } | ||
144 | |||
145 | static irqreturn_t s6i2c_interrupt_entry(int irq, void *dev_id) | ||
146 | { | ||
147 | struct s6i2c_if *iface = dev_id; | ||
148 | if (!(i2c_rd16(iface, S6_I2C_STATUS) & ((1 << S6_I2C_INTR_RXUNDER) | ||
149 | | (1 << S6_I2C_INTR_RXOVER) | ||
150 | | (1 << S6_I2C_INTR_RXFULL) | ||
151 | | (1 << S6_I2C_INTR_TXOVER) | ||
152 | | (1 << S6_I2C_INTR_TXEMPTY) | ||
153 | | (1 << S6_I2C_INTR_RDREQ) | ||
154 | | (1 << S6_I2C_INTR_TXABRT) | ||
155 | | (1 << S6_I2C_INTR_RXDONE) | ||
156 | | (1 << S6_I2C_INTR_ACTIVITY) | ||
157 | | (1 << S6_I2C_INTR_STOPDET) | ||
158 | | (1 << S6_I2C_INTR_STARTDET) | ||
159 | | (1 << S6_I2C_INTR_GENCALL)))) | ||
160 | return IRQ_NONE; | ||
161 | |||
162 | spin_lock(&iface->lock); | ||
163 | del_timer(&iface->timeout_timer); | ||
164 | s6i2c_handle_interrupt(iface); | ||
165 | spin_unlock(&iface->lock); | ||
166 | return IRQ_HANDLED; | ||
167 | } | ||
168 | |||
169 | static void s6i2c_timeout(unsigned long data) | ||
170 | { | ||
171 | struct s6i2c_if *iface = (struct s6i2c_if *)data; | ||
172 | unsigned long flags; | ||
173 | |||
174 | spin_lock_irqsave(&iface->lock, flags); | ||
175 | s6i2c_handle_interrupt(iface); | ||
176 | if (--iface->timeout_count > 0) { | ||
177 | iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; | ||
178 | add_timer(&iface->timeout_timer); | ||
179 | } else { | ||
180 | complete(&iface->complete); | ||
181 | i2c_wr16(iface, S6_I2C_INTRMASK, 0); | ||
182 | } | ||
183 | spin_unlock_irqrestore(&iface->lock, flags); | ||
184 | } | ||
185 | |||
186 | static int s6i2c_master_xfer(struct i2c_adapter *adap, | ||
187 | struct i2c_msg *msgs, int num) | ||
188 | { | ||
189 | struct s6i2c_if *iface = adap->algo_data; | ||
190 | int i; | ||
191 | if (num == 0) | ||
192 | return 0; | ||
193 | if (i2c_rd16(iface, S6_I2C_STATUS) & (1 << S6_I2C_STATUS_ACTIVITY)) | ||
194 | yield(); | ||
195 | i2c_wr16(iface, S6_I2C_INTRMASK, 0); | ||
196 | i2c_rd16(iface, S6_I2C_CLRINTR); | ||
197 | for (i = 0; i < num; i++) { | ||
198 | if (msgs[i].flags & I2C_M_TEN) { | ||
199 | dev_err(&adap->dev, | ||
200 | "s6i2c: 10 bits addr not supported\n"); | ||
201 | return -EINVAL; | ||
202 | } | ||
203 | if (msgs[i].len == 0) { | ||
204 | dev_err(&adap->dev, | ||
205 | "s6i2c: zero length message not supported\n"); | ||
206 | return -EINVAL; | ||
207 | } | ||
208 | if (msgs[i].addr != msgs[0].addr) { | ||
209 | dev_err(&adap->dev, | ||
210 | "s6i2c: multiple xfer cannot change target\n"); | ||
211 | return -EINVAL; | ||
212 | } | ||
213 | } | ||
214 | |||
215 | iface->msgs = msgs; | ||
216 | iface->msgs_num = num; | ||
217 | iface->msgs_push = 0; | ||
218 | iface->msgs_done = 0; | ||
219 | iface->push = 0; | ||
220 | iface->done = 0; | ||
221 | iface->timeout_count = 10; | ||
222 | i2c_wr16(iface, S6_I2C_TAR, msgs[0].addr); | ||
223 | i2c_wr16(iface, S6_I2C_ENABLE, 1); | ||
224 | i2c_wr16(iface, S6_I2C_INTRMASK, (1 << S6_I2C_INTR_TXEMPTY) | | ||
225 | (1 << S6_I2C_INTR_TXABRT)); | ||
226 | |||
227 | iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; | ||
228 | add_timer(&iface->timeout_timer); | ||
229 | wait_for_completion(&iface->complete); | ||
230 | del_timer_sync(&iface->timeout_timer); | ||
231 | while (i2c_rd32(iface, S6_I2C_TXFLR) > 0) | ||
232 | schedule(); | ||
233 | while (i2c_rd16(iface, S6_I2C_STATUS) & (1 << S6_I2C_STATUS_ACTIVITY)) | ||
234 | schedule(); | ||
235 | |||
236 | i2c_wr16(iface, S6_I2C_INTRMASK, 0); | ||
237 | i2c_wr16(iface, S6_I2C_ENABLE, 0); | ||
238 | return iface->msgs_done; | ||
239 | } | ||
240 | |||
241 | static u32 s6i2c_functionality(struct i2c_adapter *adap) | ||
242 | { | ||
243 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; | ||
244 | } | ||
245 | |||
246 | static struct i2c_algorithm s6i2c_algorithm = { | ||
247 | .master_xfer = s6i2c_master_xfer, | ||
248 | .functionality = s6i2c_functionality, | ||
249 | }; | ||
250 | |||
251 | static u16 __devinit nanoseconds_on_clk(struct s6i2c_if *iface, u32 ns) | ||
252 | { | ||
253 | u32 dividend = ((clk_get_rate(iface->clk) / 1000) * ns) / 1000000; | ||
254 | if (dividend > 0xffff) | ||
255 | return 0xffff; | ||
256 | return dividend; | ||
257 | } | ||
258 | |||
259 | static int __devinit s6i2c_probe(struct platform_device *dev) | ||
260 | { | ||
261 | struct s6i2c_if *iface = &s6i2c_if; | ||
262 | struct i2c_adapter *p_adap; | ||
263 | const char *clock; | ||
264 | int bus_num, rc; | ||
265 | spin_lock_init(&iface->lock); | ||
266 | init_completion(&iface->complete); | ||
267 | iface->irq = platform_get_irq(dev, 0); | ||
268 | if (iface->irq < 0) { | ||
269 | rc = iface->irq; | ||
270 | goto err_out; | ||
271 | } | ||
272 | iface->res = platform_get_resource(dev, IORESOURCE_MEM, 0); | ||
273 | if (!iface->res) { | ||
274 | rc = -ENXIO; | ||
275 | goto err_out; | ||
276 | } | ||
277 | iface->res = request_mem_region(iface->res->start, | ||
278 | resource_size(iface->res), | ||
279 | dev->dev.bus_id); | ||
280 | if (!iface->res) { | ||
281 | rc = -EBUSY; | ||
282 | goto err_out; | ||
283 | } | ||
284 | iface->reg = ioremap_nocache(iface->res->start, | ||
285 | resource_size(iface->res)); | ||
286 | if (!iface->reg) { | ||
287 | rc = -ENOMEM; | ||
288 | goto err_reg; | ||
289 | } | ||
290 | |||
291 | clock = 0; | ||
292 | bus_num = -1; | ||
293 | if (dev->dev.platform_data) { | ||
294 | struct s6_i2c_platform_data *pdata = dev->dev.platform_data; | ||
295 | bus_num = pdata->bus_num; | ||
296 | clock = pdata->clock; | ||
297 | } | ||
298 | iface->clk = clk_get(&dev->dev, clock); | ||
299 | if (IS_ERR(iface->clk)) { | ||
300 | rc = PTR_ERR(iface->clk); | ||
301 | goto err_map; | ||
302 | } | ||
303 | rc = clk_enable(iface->clk); | ||
304 | if (rc < 0) | ||
305 | goto err_clk_put; | ||
306 | init_timer(&iface->timeout_timer); | ||
307 | iface->timeout_timer.function = s6i2c_timeout; | ||
308 | iface->timeout_timer.data = (unsigned long)iface; | ||
309 | |||
310 | p_adap = &iface->adap; | ||
311 | strlcpy(p_adap->name, dev->name, sizeof(p_adap->name)); | ||
312 | p_adap->algo = &s6i2c_algorithm; | ||
313 | p_adap->algo_data = iface; | ||
314 | p_adap->nr = bus_num; | ||
315 | p_adap->class = 0; | ||
316 | p_adap->dev.parent = &dev->dev; | ||
317 | i2c_wr16(iface, S6_I2C_INTRMASK, 0); | ||
318 | rc = request_irq(iface->irq, s6i2c_interrupt_entry, | ||
319 | IRQF_SHARED, dev->name, iface); | ||
320 | if (rc) { | ||
321 | dev_err(&p_adap->dev, "s6i2c: cant get IRQ %d\n", iface->irq); | ||
322 | goto err_clk_dis; | ||
323 | } | ||
324 | |||
325 | i2c_wr16(iface, S6_I2C_ENABLE, 0); | ||
326 | udelay(1); | ||
327 | i2c_wr32(iface, S6_I2C_SRESET, 1 << S6_I2C_SRESET_IC_SRST); | ||
328 | i2c_wr16(iface, S6_I2C_CLRTXABRT, 1); | ||
329 | i2c_wr16(iface, S6_I2C_CON, | ||
330 | (1 << S6_I2C_CON_MASTER) | | ||
331 | (S6_I2C_CON_SPEED_NORMAL << S6_I2C_CON_SPEED) | | ||
332 | (0 << S6_I2C_CON_10BITSLAVE) | | ||
333 | (0 << S6_I2C_CON_10BITMASTER) | | ||
334 | (1 << S6_I2C_CON_RESTARTENA) | | ||
335 | (1 << S6_I2C_CON_SLAVEDISABLE)); | ||
336 | i2c_wr16(iface, S6_I2C_SSHCNT, nanoseconds_on_clk(iface, 4000)); | ||
337 | i2c_wr16(iface, S6_I2C_SSLCNT, nanoseconds_on_clk(iface, 4700)); | ||
338 | i2c_wr16(iface, S6_I2C_FSHCNT, nanoseconds_on_clk(iface, 600)); | ||
339 | i2c_wr16(iface, S6_I2C_FSLCNT, nanoseconds_on_clk(iface, 1300)); | ||
340 | i2c_wr16(iface, S6_I2C_RXTL, 0); | ||
341 | i2c_wr16(iface, S6_I2C_TXTL, 0); | ||
342 | |||
343 | platform_set_drvdata(dev, iface); | ||
344 | if (bus_num < 0) | ||
345 | rc = i2c_add_adapter(p_adap); | ||
346 | else | ||
347 | rc = i2c_add_numbered_adapter(p_adap); | ||
348 | if (rc) | ||
349 | goto err_irq_free; | ||
350 | return 0; | ||
351 | |||
352 | err_irq_free: | ||
353 | free_irq(iface->irq, iface); | ||
354 | err_clk_dis: | ||
355 | clk_disable(iface->clk); | ||
356 | err_clk_put: | ||
357 | clk_put(iface->clk); | ||
358 | err_map: | ||
359 | iounmap(iface->reg); | ||
360 | err_reg: | ||
361 | release_mem_region(iface->res->start, | ||
362 | resource_size(iface->res)); | ||
363 | err_out: | ||
364 | return rc; | ||
365 | } | ||
366 | |||
367 | static int __devexit s6i2c_remove(struct platform_device *pdev) | ||
368 | { | ||
369 | struct s6i2c_if *iface = platform_get_drvdata(pdev); | ||
370 | i2c_wr16(iface, S6_I2C_ENABLE, 0); | ||
371 | platform_set_drvdata(pdev, NULL); | ||
372 | i2c_del_adapter(&iface->adap); | ||
373 | free_irq(iface->irq, iface); | ||
374 | clk_disable(iface->clk); | ||
375 | clk_put(iface->clk); | ||
376 | iounmap(iface->reg); | ||
377 | release_mem_region(iface->res->start, | ||
378 | resource_size(iface->res)); | ||
379 | return 0; | ||
380 | } | ||
381 | |||
382 | static struct platform_driver s6i2c_driver = { | ||
383 | .probe = s6i2c_probe, | ||
384 | .remove = __devexit_p(s6i2c_remove), | ||
385 | .driver = { | ||
386 | .name = DRV_NAME, | ||
387 | .owner = THIS_MODULE, | ||
388 | }, | ||
389 | }; | ||
390 | |||
391 | static int __init s6i2c_init(void) | ||
392 | { | ||
393 | pr_info("I2C: S6000 I2C driver\n"); | ||
394 | return platform_driver_register(&s6i2c_driver); | ||
395 | } | ||
396 | |||
397 | static void __exit s6i2c_exit(void) | ||
398 | { | ||
399 | platform_driver_unregister(&s6i2c_driver); | ||
400 | } | ||
401 | |||
402 | MODULE_DESCRIPTION("I2C-Bus adapter routines for S6000 I2C"); | ||
403 | MODULE_LICENSE("GPL"); | ||
404 | MODULE_ALIAS("platform:" DRV_NAME); | ||
405 | |||
406 | subsys_initcall(s6i2c_init); | ||
407 | module_exit(s6i2c_exit); | ||