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-rw-r--r--drivers/sbus/char/vfc_i2c.c335
1 files changed, 0 insertions, 335 deletions
diff --git a/drivers/sbus/char/vfc_i2c.c b/drivers/sbus/char/vfc_i2c.c
deleted file mode 100644
index 32b986e0ed78..000000000000
--- a/drivers/sbus/char/vfc_i2c.c
+++ /dev/null
@@ -1,335 +0,0 @@
1/*
2 * drivers/sbus/char/vfc_i2c.c
3 *
4 * Driver for the Videopix Frame Grabber.
5 *
6 * Functions that support the Phillips i2c(I squared C) bus on the vfc
7 * Documentation for the Phillips I2C bus can be found on the
8 * phillips home page
9 *
10 * Copyright (C) 1996 Manish Vachharajani (mvachhar@noc.rutgers.edu)
11 *
12 */
13
14/* NOTE: It seems to me that the documentation regarding the
15pcd8584t/pcf8584 does not show the correct way to address the i2c bus.
16Based on the information on the I2C bus itself and the remainder of
17the Phillips docs the following algorithms appear to be correct. I am
18fairly certain that the flowcharts in the phillips docs are wrong. */
19
20
21#include <linux/kernel.h>
22#include <linux/string.h>
23#include <linux/slab.h>
24#include <linux/errno.h>
25#include <linux/sched.h>
26#include <linux/wait.h>
27#include <linux/delay.h>
28#include <asm/openprom.h>
29#include <asm/oplib.h>
30#include <asm/io.h>
31#include <asm/system.h>
32#include <asm/sbus.h>
33
34#if 0
35#define VFC_I2C_DEBUG
36#endif
37
38#include "vfc.h"
39#include "vfc_i2c.h"
40
41#define WRITE_S1(__val) \
42 sbus_writel(__val, &dev->regs->i2c_s1)
43#define WRITE_REG(__val) \
44 sbus_writel(__val, &dev->regs->i2c_reg)
45
46#define VFC_I2C_READ (0x1)
47#define VFC_I2C_WRITE (0x0)
48
49/******
50 The i2c bus controller chip on the VFC is a pcd8584t, but
51 phillips claims it doesn't exist. As far as I can tell it is
52 identical to the PCF8584 so I treat it like it is the pcf8584.
53
54 NOTE: The pcf8584 only cares
55 about the msb of the word you feed it
56*****/
57
58int vfc_pcf8584_init(struct vfc_dev *dev)
59{
60 /* This will also choose register S0_OWN so we can set it. */
61 WRITE_S1(RESET);
62
63 /* The pcf8584 shifts this value left one bit and uses
64 * it as its i2c bus address.
65 */
66 WRITE_REG(0x55000000);
67
68 /* This will set the i2c bus at the same speed sun uses,
69 * and set another magic bit.
70 */
71 WRITE_S1(SELECT(S2));
72 WRITE_REG(0x14000000);
73
74 /* Enable the serial port, idle the i2c bus and set
75 * the data reg to s0.
76 */
77 WRITE_S1(CLEAR_I2C_BUS);
78 udelay(100);
79 return 0;
80}
81
82void vfc_i2c_delay_no_busy(struct vfc_dev *dev, unsigned long usecs)
83{
84 schedule_timeout_uninterruptible(usecs_to_jiffies(usecs));
85}
86
87void inline vfc_i2c_delay(struct vfc_dev *dev)
88{
89 vfc_i2c_delay_no_busy(dev, 100);
90}
91
92int vfc_init_i2c_bus(struct vfc_dev *dev)
93{
94 WRITE_S1(ENABLE_SERIAL | SELECT(S0) | ACK);
95 vfc_i2c_reset_bus(dev);
96 return 0;
97}
98
99int vfc_i2c_reset_bus(struct vfc_dev *dev)
100{
101 VFC_I2C_DEBUG_PRINTK((KERN_DEBUG "vfc%d: Resetting the i2c bus\n",
102 dev->instance));
103 if(dev == NULL)
104 return -EINVAL;
105 if(dev->regs == NULL)
106 return -EINVAL;
107 WRITE_S1(SEND_I2C_STOP);
108 WRITE_S1(SEND_I2C_STOP | ACK);
109 vfc_i2c_delay(dev);
110 WRITE_S1(CLEAR_I2C_BUS);
111 VFC_I2C_DEBUG_PRINTK((KERN_DEBUG "vfc%d: I2C status %x\n",
112 dev->instance,
113 sbus_readl(&dev->regs->i2c_s1)));
114 return 0;
115}
116
117static int vfc_i2c_wait_for_bus(struct vfc_dev *dev)
118{
119 int timeout = 1000;
120
121 while(!(sbus_readl(&dev->regs->i2c_s1) & BB)) {
122 if(!(timeout--))
123 return -ETIMEDOUT;
124 vfc_i2c_delay(dev);
125 }
126 return 0;
127}
128
129static int vfc_i2c_wait_for_pin(struct vfc_dev *dev, int ack)
130{
131 int timeout = 1000;
132 int s1;
133
134 while ((s1 = sbus_readl(&dev->regs->i2c_s1)) & PIN) {
135 if (!(timeout--))
136 return -ETIMEDOUT;
137 vfc_i2c_delay(dev);
138 }
139 if (ack == VFC_I2C_ACK_CHECK) {
140 if(s1 & LRB)
141 return -EIO;
142 }
143 return 0;
144}
145
146#define SHIFT(a) ((a) << 24)
147static int vfc_i2c_xmit_addr(struct vfc_dev *dev, unsigned char addr,
148 char mode)
149{
150 int ret, raddr;
151#if 1
152 WRITE_S1(SEND_I2C_STOP | ACK);
153 WRITE_S1(SELECT(S0) | ENABLE_SERIAL);
154 vfc_i2c_delay(dev);
155#endif
156
157 switch(mode) {
158 case VFC_I2C_READ:
159 raddr = SHIFT(((unsigned int)addr | 0x1));
160 WRITE_REG(raddr);
161 VFC_I2C_DEBUG_PRINTK(("vfc%d: receiving from i2c addr 0x%x\n",
162 dev->instance, addr | 0x1));
163 break;
164 case VFC_I2C_WRITE:
165 raddr = SHIFT((unsigned int)addr & ~0x1);
166 WRITE_REG(raddr);
167 VFC_I2C_DEBUG_PRINTK(("vfc%d: sending to i2c addr 0x%x\n",
168 dev->instance, addr & ~0x1));
169 break;
170 default:
171 return -EINVAL;
172 };
173
174 WRITE_S1(SEND_I2C_START);
175 vfc_i2c_delay(dev);
176 ret = vfc_i2c_wait_for_pin(dev,VFC_I2C_ACK_CHECK); /* We wait
177 for the
178 i2c send
179 to finish
180 here but
181 Sun
182 doesn't,
183 hmm */
184 if (ret) {
185 printk(KERN_ERR "vfc%d: VFC xmit addr timed out or no ack\n",
186 dev->instance);
187 return ret;
188 } else if (mode == VFC_I2C_READ) {
189 if ((ret = sbus_readl(&dev->regs->i2c_reg) & 0xff000000) != raddr) {
190 printk(KERN_WARNING
191 "vfc%d: returned slave address "
192 "mismatch(%x,%x)\n",
193 dev->instance, raddr, ret);
194 }
195 }
196 return 0;
197}
198
199static int vfc_i2c_xmit_byte(struct vfc_dev *dev,unsigned char *byte)
200{
201 int ret;
202 u32 val = SHIFT((unsigned int)*byte);
203
204 WRITE_REG(val);
205
206 ret = vfc_i2c_wait_for_pin(dev, VFC_I2C_ACK_CHECK);
207 switch(ret) {
208 case -ETIMEDOUT:
209 printk(KERN_ERR "vfc%d: VFC xmit byte timed out or no ack\n",
210 dev->instance);
211 break;
212 case -EIO:
213 ret = XMIT_LAST_BYTE;
214 break;
215 default:
216 break;
217 };
218
219 return ret;
220}
221
222static int vfc_i2c_recv_byte(struct vfc_dev *dev, unsigned char *byte,
223 int last)
224{
225 int ret;
226
227 if (last) {
228 WRITE_REG(NEGATIVE_ACK);
229 VFC_I2C_DEBUG_PRINTK(("vfc%d: sending negative ack\n",
230 dev->instance));
231 } else {
232 WRITE_S1(ACK);
233 }
234
235 ret = vfc_i2c_wait_for_pin(dev, VFC_I2C_NO_ACK_CHECK);
236 if(ret) {
237 printk(KERN_ERR "vfc%d: "
238 "VFC recv byte timed out\n",
239 dev->instance);
240 }
241 *byte = (sbus_readl(&dev->regs->i2c_reg)) >> 24;
242 return ret;
243}
244
245int vfc_i2c_recvbuf(struct vfc_dev *dev, unsigned char addr,
246 char *buf, int count)
247{
248 int ret, last;
249
250 if(!(count && buf && dev && dev->regs) )
251 return -EINVAL;
252
253 if ((ret = vfc_i2c_wait_for_bus(dev))) {
254 printk(KERN_ERR "vfc%d: VFC I2C bus busy\n", dev->instance);
255 return ret;
256 }
257
258 if ((ret = vfc_i2c_xmit_addr(dev, addr, VFC_I2C_READ))) {
259 WRITE_S1(SEND_I2C_STOP);
260 vfc_i2c_delay(dev);
261 return ret;
262 }
263
264 last = 0;
265 while (count--) {
266 if (!count)
267 last = 1;
268 if ((ret = vfc_i2c_recv_byte(dev, buf, last))) {
269 printk(KERN_ERR "vfc%d: "
270 "VFC error while receiving byte\n",
271 dev->instance);
272 WRITE_S1(SEND_I2C_STOP);
273 ret = -EINVAL;
274 }
275 buf++;
276 }
277 WRITE_S1(SEND_I2C_STOP | ACK);
278 vfc_i2c_delay(dev);
279 return ret;
280}
281
282int vfc_i2c_sendbuf(struct vfc_dev *dev, unsigned char addr,
283 char *buf, int count)
284{
285 int ret;
286
287 if (!(buf && dev && dev->regs))
288 return -EINVAL;
289
290 if ((ret = vfc_i2c_wait_for_bus(dev))) {
291 printk(KERN_ERR "vfc%d: VFC I2C bus busy\n", dev->instance);
292 return ret;
293 }
294
295 if ((ret = vfc_i2c_xmit_addr(dev, addr, VFC_I2C_WRITE))) {
296 WRITE_S1(SEND_I2C_STOP);
297 vfc_i2c_delay(dev);
298 return ret;
299 }
300
301 while(count--) {
302 ret = vfc_i2c_xmit_byte(dev, buf);
303 switch(ret) {
304 case XMIT_LAST_BYTE:
305 VFC_I2C_DEBUG_PRINTK(("vfc%d: "
306 "Receiver ended transmission with "
307 " %d bytes remaining\n",
308 dev->instance, count));
309 ret = 0;
310 goto done;
311 break;
312 case 0:
313 break;
314 default:
315 printk(KERN_ERR "vfc%d: "
316 "VFC error while sending byte\n", dev->instance);
317 break;
318 };
319
320 buf++;
321 }
322done:
323 WRITE_S1(SEND_I2C_STOP | ACK);
324 vfc_i2c_delay(dev);
325 return ret;
326}
327
328
329
330
331
332
333
334
335
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-20 02:30:42 -0500