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-rw-r--r--drivers/acorn/char/Makefile1
-rw-r--r--drivers/acorn/char/i2c.c368
-rw-r--r--drivers/acorn/char/pcf8583.c284
-rw-r--r--drivers/acorn/char/pcf8583.h41
-rw-r--r--drivers/i2c/busses/Kconfig10
-rw-r--r--drivers/i2c/busses/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-acorn.c97
7 files changed, 108 insertions, 694 deletions
diff --git a/drivers/acorn/char/Makefile b/drivers/acorn/char/Makefile
index 2fa9a8bf48a0..d006c9f168d2 100644
--- a/drivers/acorn/char/Makefile
+++ b/drivers/acorn/char/Makefile
@@ -2,5 +2,4 @@
2# Makefile for the acorn character device drivers. 2# Makefile for the acorn character device drivers.
3# 3#
4 4
5obj-$(CONFIG_ARCH_ACORN) += i2c.o pcf8583.o
6obj-$(CONFIG_L7200_KEYB) += defkeymap-l7200.o keyb_l7200.o 5obj-$(CONFIG_L7200_KEYB) += defkeymap-l7200.o keyb_l7200.o
diff --git a/drivers/acorn/char/i2c.c b/drivers/acorn/char/i2c.c
deleted file mode 100644
index d276fd14d63a..000000000000
--- a/drivers/acorn/char/i2c.c
+++ /dev/null
@@ -1,368 +0,0 @@
1/*
2 * linux/drivers/acorn/char/i2c.c
3 *
4 * Copyright (C) 2000 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * ARM IOC/IOMD i2c driver.
11 *
12 * On Acorn machines, the following i2c devices are on the bus:
13 * - PCF8583 real time clock & static RAM
14 */
15#include <linux/capability.h>
16#include <linux/init.h>
17#include <linux/time.h>
18#include <linux/miscdevice.h>
19#include <linux/rtc.h>
20#include <linux/i2c.h>
21#include <linux/i2c-algo-bit.h>
22#include <linux/fs.h>
23
24#include <asm/hardware.h>
25#include <asm/io.h>
26#include <asm/hardware/ioc.h>
27#include <asm/system.h>
28#include <asm/uaccess.h>
29
30#include "pcf8583.h"
31
32extern int (*set_rtc)(void);
33
34static struct i2c_client *rtc_client;
35static const unsigned char days_in_mon[] =
36 { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
37
38#define CMOS_CHECKSUM (63)
39
40/*
41 * Acorn machines store the year in the static RAM at
42 * location 128.
43 */
44#define CMOS_YEAR (64 + 128)
45
46static inline int rtc_command(int cmd, void *data)
47{
48 int ret = -EIO;
49
50 if (rtc_client)
51 ret = rtc_client->driver->command(rtc_client, cmd, data);
52
53 return ret;
54}
55
56/*
57 * Update the century + year bytes in the CMOS RAM, ensuring
58 * that the check byte is correctly adjusted for the change.
59 */
60static int rtc_update_year(unsigned int new_year)
61{
62 unsigned char yr[2], chk;
63 struct mem cmos_year = { CMOS_YEAR, sizeof(yr), yr };
64 struct mem cmos_check = { CMOS_CHECKSUM, 1, &chk };
65 int ret;
66
67 ret = rtc_command(MEM_READ, &cmos_check);
68 if (ret)
69 goto out;
70 ret = rtc_command(MEM_READ, &cmos_year);
71 if (ret)
72 goto out;
73
74 chk -= yr[1] + yr[0];
75
76 yr[1] = new_year / 100;
77 yr[0] = new_year % 100;
78
79 chk += yr[1] + yr[0];
80
81 ret = rtc_command(MEM_WRITE, &cmos_year);
82 if (ret == 0)
83 ret = rtc_command(MEM_WRITE, &cmos_check);
84 out:
85 return ret;
86}
87
88/*
89 * Read the current RTC time and date, and update xtime.
90 */
91static void get_rtc_time(struct rtc_tm *rtctm, unsigned int *year)
92{
93 unsigned char ctrl, yr[2];
94 struct mem rtcmem = { CMOS_YEAR, sizeof(yr), yr };
95 int real_year, year_offset;
96
97 /*
98 * Ensure that the RTC is running.
99 */
100 rtc_command(RTC_GETCTRL, &ctrl);
101 if (ctrl & 0xc0) {
102 unsigned char new_ctrl = ctrl & ~0xc0;
103
104 printk(KERN_WARNING "RTC: resetting control %02x -> %02x\n",
105 ctrl, new_ctrl);
106
107 rtc_command(RTC_SETCTRL, &new_ctrl);
108 }
109
110 if (rtc_command(RTC_GETDATETIME, rtctm) ||
111 rtc_command(MEM_READ, &rtcmem))
112 return;
113
114 real_year = yr[0];
115
116 /*
117 * The RTC year holds the LSB two bits of the current
118 * year, which should reflect the LSB two bits of the
119 * CMOS copy of the year. Any difference indicates
120 * that we have to correct the CMOS version.
121 */
122 year_offset = rtctm->year_off - (real_year & 3);
123 if (year_offset < 0)
124 /*
125 * RTC year wrapped. Adjust it appropriately.
126 */
127 year_offset += 4;
128
129 *year = real_year + year_offset + yr[1] * 100;
130}
131
132static int set_rtc_time(struct rtc_tm *rtctm, unsigned int year)
133{
134 unsigned char leap;
135 int ret;
136
137 leap = (!(year % 4) && (year % 100)) || !(year % 400);
138
139 if (rtctm->mon > 12 || rtctm->mon == 0 || rtctm->mday == 0)
140 return -EINVAL;
141
142 if (rtctm->mday > (days_in_mon[rtctm->mon] + (rtctm->mon == 2 && leap)))
143 return -EINVAL;
144
145 if (rtctm->hours >= 24 || rtctm->mins >= 60 || rtctm->secs >= 60)
146 return -EINVAL;
147
148 /*
149 * The RTC's own 2-bit year must reflect the least
150 * significant two bits of the CMOS year.
151 */
152 rtctm->year_off = (year % 100) & 3;
153
154 ret = rtc_command(RTC_SETDATETIME, rtctm);
155 if (ret == 0)
156 ret = rtc_update_year(year);
157
158 return ret;
159}
160
161/*
162 * Set the RTC time only. Note that
163 * we do not touch the date.
164 */
165static int k_set_rtc_time(void)
166{
167 struct rtc_tm new_rtctm, old_rtctm;
168 unsigned long nowtime = xtime.tv_sec;
169
170 if (rtc_command(RTC_GETDATETIME, &old_rtctm))
171 return 0;
172
173 new_rtctm.cs = xtime.tv_nsec / 10000000;
174 new_rtctm.secs = nowtime % 60; nowtime /= 60;
175 new_rtctm.mins = nowtime % 60; nowtime /= 60;
176 new_rtctm.hours = nowtime % 24;
177
178 /*
179 * avoid writing when we're going to change the day
180 * of the month. We will retry in the next minute.
181 * This basically means that if the RTC must not drift
182 * by more than 1 minute in 11 minutes.
183 *
184 * [ rtc: 1/1/2000 23:58:00, real 2/1/2000 00:01:00,
185 * rtc gets set to 1/1/2000 00:01:00 ]
186 */
187 if ((old_rtctm.hours == 23 && old_rtctm.mins == 59) ||
188 (new_rtctm.hours == 23 && new_rtctm.mins == 59))
189 return 1;
190
191 return rtc_command(RTC_SETTIME, &new_rtctm);
192}
193
194static int rtc_ioctl(struct inode *inode, struct file *file,
195 unsigned int cmd, unsigned long arg)
196{
197 unsigned int year;
198 struct rtc_time rtctm;
199 struct rtc_tm rtc_raw;
200
201 switch (cmd) {
202 case RTC_ALM_READ:
203 case RTC_ALM_SET:
204 break;
205
206 case RTC_RD_TIME:
207 memset(&rtctm, 0, sizeof(struct rtc_time));
208 get_rtc_time(&rtc_raw, &year);
209 rtctm.tm_sec = rtc_raw.secs;
210 rtctm.tm_min = rtc_raw.mins;
211 rtctm.tm_hour = rtc_raw.hours;
212 rtctm.tm_mday = rtc_raw.mday;
213 rtctm.tm_mon = rtc_raw.mon - 1; /* month starts at 0 */
214 rtctm.tm_year = year - 1900; /* starts at 1900 */
215 return copy_to_user((void *)arg, &rtctm, sizeof(rtctm))
216 ? -EFAULT : 0;
217
218 case RTC_SET_TIME:
219 if (!capable(CAP_SYS_TIME))
220 return -EACCES;
221
222 if (copy_from_user(&rtctm, (void *)arg, sizeof(rtctm)))
223 return -EFAULT;
224 rtc_raw.secs = rtctm.tm_sec;
225 rtc_raw.mins = rtctm.tm_min;
226 rtc_raw.hours = rtctm.tm_hour;
227 rtc_raw.mday = rtctm.tm_mday;
228 rtc_raw.mon = rtctm.tm_mon + 1;
229 year = rtctm.tm_year + 1900;
230 return set_rtc_time(&rtc_raw, year);
231 break;
232
233 case RTC_EPOCH_READ:
234 return put_user(1900, (unsigned long *)arg);
235
236 }
237 return -EINVAL;
238}
239
240static const struct file_operations rtc_fops = {
241 .ioctl = rtc_ioctl,
242};
243
244static struct miscdevice rtc_dev = {
245 .minor = RTC_MINOR,
246 .name = "rtc",
247 .fops = &rtc_fops,
248};
249
250/* IOC / IOMD i2c driver */
251
252#define FORCE_ONES 0xdc
253#define SCL 0x02
254#define SDA 0x01
255
256/*
257 * We must preserve all non-i2c output bits in IOC_CONTROL.
258 * Note also that we need to preserve the value of SCL and
259 * SDA outputs as well (which may be different from the
260 * values read back from IOC_CONTROL).
261 */
262static u_int force_ones;
263
264static void ioc_setscl(void *data, int state)
265{
266 u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA);
267 u_int ones = force_ones;
268
269 if (state)
270 ones |= SCL;
271 else
272 ones &= ~SCL;
273
274 force_ones = ones;
275
276 ioc_writeb(ioc_control | ones, IOC_CONTROL);
277}
278
279static void ioc_setsda(void *data, int state)
280{
281 u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA);
282 u_int ones = force_ones;
283
284 if (state)
285 ones |= SDA;
286 else
287 ones &= ~SDA;
288
289 force_ones = ones;
290
291 ioc_writeb(ioc_control | ones, IOC_CONTROL);
292}
293
294static int ioc_getscl(void *data)
295{
296 return (ioc_readb(IOC_CONTROL) & SCL) != 0;
297}
298
299static int ioc_getsda(void *data)
300{
301 return (ioc_readb(IOC_CONTROL) & SDA) != 0;
302}
303
304static struct i2c_algo_bit_data ioc_data = {
305 .setsda = ioc_setsda,
306 .setscl = ioc_setscl,
307 .getsda = ioc_getsda,
308 .getscl = ioc_getscl,
309 .udelay = 80,
310 .timeout = 100
311};
312
313static int ioc_client_reg(struct i2c_client *client)
314{
315 if (client->driver->id == I2C_DRIVERID_PCF8583 &&
316 client->addr == 0x50) {
317 struct rtc_tm rtctm;
318 unsigned int year;
319 struct timespec tv;
320
321 rtc_client = client;
322 get_rtc_time(&rtctm, &year);
323
324 tv.tv_nsec = rtctm.cs * 10000000;
325 tv.tv_sec = mktime(year, rtctm.mon, rtctm.mday,
326 rtctm.hours, rtctm.mins, rtctm.secs);
327 do_settimeofday(&tv);
328 set_rtc = k_set_rtc_time;
329 }
330
331 return 0;
332}
333
334static int ioc_client_unreg(struct i2c_client *client)
335{
336 if (client == rtc_client) {
337 set_rtc = NULL;
338 rtc_client = NULL;
339 }
340
341 return 0;
342}
343
344static struct i2c_adapter ioc_ops = {
345 .id = I2C_HW_B_IOC,
346 .algo_data = &ioc_data,
347 .client_register = ioc_client_reg,
348 .client_unregister = ioc_client_unreg,
349};
350
351static int __init i2c_ioc_init(void)
352{
353 int ret;
354
355 force_ones = FORCE_ONES | SCL | SDA;
356
357 ret = i2c_bit_add_bus(&ioc_ops);
358
359 if (ret >= 0){
360 ret = misc_register(&rtc_dev);
361 if(ret < 0)
362 i2c_del_adapter(&ioc_ops);
363 }
364
365 return ret;
366}
367
368__initcall(i2c_ioc_init);
diff --git a/drivers/acorn/char/pcf8583.c b/drivers/acorn/char/pcf8583.c
deleted file mode 100644
index 9b49f316ae92..000000000000
--- a/drivers/acorn/char/pcf8583.c
+++ /dev/null
@@ -1,284 +0,0 @@
1/*
2 * linux/drivers/acorn/char/pcf8583.c
3 *
4 * Copyright (C) 2000 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Driver for PCF8583 RTC & RAM chip
11 */
12#include <linux/module.h>
13#include <linux/i2c.h>
14#include <linux/slab.h>
15#include <linux/string.h>
16#include <linux/mc146818rtc.h>
17#include <linux/init.h>
18#include <linux/errno.h>
19#include <linux/bcd.h>
20
21#include "pcf8583.h"
22
23static struct i2c_driver pcf8583_driver;
24
25static unsigned short ignore[] = { I2C_CLIENT_END };
26static unsigned short normal_addr[] = { 0x50, I2C_CLIENT_END };
27static unsigned short *forces[] = { NULL };
28
29static struct i2c_client_address_data addr_data = {
30 .normal_i2c = normal_addr,
31 .probe = ignore,
32 .ignore = ignore,
33 .forces = forces,
34};
35
36#define set_ctrl(x, v) i2c_set_clientdata(x, (void *)(unsigned int)(v))
37#define get_ctrl(x) ((unsigned int)i2c_get_clientdata(x))
38
39static int
40pcf8583_attach(struct i2c_adapter *adap, int addr, int kind)
41{
42 struct i2c_client *c;
43 unsigned char buf[1], ad[1] = { 0 };
44 struct i2c_msg msgs[2] = {
45 {
46 .addr = addr,
47 .flags = 0,
48 .len = 1,
49 .buf = ad,
50 }, {
51 .addr = addr,
52 .flags = I2C_M_RD,
53 .len = 1,
54 .buf = buf,
55 }
56 };
57
58 c = kmalloc(sizeof(*c), GFP_KERNEL);
59 if (!c)
60 return -ENOMEM;
61
62 memset(c, 0, sizeof(*c));
63 c->addr = addr;
64 c->adapter = adap;
65 c->driver = &pcf8583_driver;
66
67 if (i2c_transfer(c->adapter, msgs, 2) == 2)
68 set_ctrl(c, buf[0]);
69
70 return i2c_attach_client(c);
71}
72
73static int
74pcf8583_probe(struct i2c_adapter *adap)
75{
76 return i2c_probe(adap, &addr_data, pcf8583_attach);
77}
78
79static int
80pcf8583_detach(struct i2c_client *client)
81{
82 i2c_detach_client(client);
83 kfree(client);
84 return 0;
85}
86
87static int
88pcf8583_get_datetime(struct i2c_client *client, struct rtc_tm *dt)
89{
90 unsigned char buf[8], addr[1] = { 1 };
91 struct i2c_msg msgs[2] = {
92 {
93 .addr = client->addr,
94 .flags = 0,
95 .len = 1,
96 .buf = addr,
97 }, {
98 .addr = client->addr,
99 .flags = I2C_M_RD,
100 .len = 6,
101 .buf = buf,
102 }
103 };
104 int ret = -EIO;
105
106 memset(buf, 0, sizeof(buf));
107
108 ret = i2c_transfer(client->adapter, msgs, 2);
109 if (ret == 2) {
110 dt->year_off = buf[4] >> 6;
111 dt->wday = buf[5] >> 5;
112
113 buf[4] &= 0x3f;
114 buf[5] &= 0x1f;
115
116 dt->cs = BCD_TO_BIN(buf[0]);
117 dt->secs = BCD_TO_BIN(buf[1]);
118 dt->mins = BCD_TO_BIN(buf[2]);
119 dt->hours = BCD_TO_BIN(buf[3]);
120 dt->mday = BCD_TO_BIN(buf[4]);
121 dt->mon = BCD_TO_BIN(buf[5]);
122
123 ret = 0;
124 }
125
126 return ret;
127}
128
129static int
130pcf8583_set_datetime(struct i2c_client *client, struct rtc_tm *dt, int datetoo)
131{
132 unsigned char buf[8];
133 int ret, len = 6;
134
135 buf[0] = 0;
136 buf[1] = get_ctrl(client) | 0x80;
137 buf[2] = BIN_TO_BCD(dt->cs);
138 buf[3] = BIN_TO_BCD(dt->secs);
139 buf[4] = BIN_TO_BCD(dt->mins);
140 buf[5] = BIN_TO_BCD(dt->hours);
141
142 if (datetoo) {
143 len = 8;
144 buf[6] = BIN_TO_BCD(dt->mday) | (dt->year_off << 6);
145 buf[7] = BIN_TO_BCD(dt->mon) | (dt->wday << 5);
146 }
147
148 ret = i2c_master_send(client, (char *)buf, len);
149 if (ret == len)
150 ret = 0;
151
152 buf[1] = get_ctrl(client);
153 i2c_master_send(client, (char *)buf, 2);
154
155 return ret;
156}
157
158static int
159pcf8583_get_ctrl(struct i2c_client *client, unsigned char *ctrl)
160{
161 *ctrl = get_ctrl(client);
162 return 0;
163}
164
165static int
166pcf8583_set_ctrl(struct i2c_client *client, unsigned char *ctrl)
167{
168 unsigned char buf[2];
169
170 buf[0] = 0;
171 buf[1] = *ctrl;
172 set_ctrl(client, *ctrl);
173
174 return i2c_master_send(client, (char *)buf, 2);
175}
176
177static int
178pcf8583_read_mem(struct i2c_client *client, struct mem *mem)
179{
180 unsigned char addr[1];
181 struct i2c_msg msgs[2] = {
182 {
183 .addr = client->addr,
184 .flags = 0,
185 .len = 1,
186 .buf = addr,
187 }, {
188 .addr = client->addr,
189 .flags = I2C_M_RD,
190 .len = mem->nr,
191 .buf = mem->data,
192 }
193 };
194
195 if (mem->loc < 8)
196 return -EINVAL;
197
198 addr[0] = mem->loc;
199
200 return i2c_transfer(client->adapter, msgs, 2) == 2 ? 0 : -EIO;
201}
202
203static int
204pcf8583_write_mem(struct i2c_client *client, struct mem *mem)
205{
206 unsigned char addr[1];
207 struct i2c_msg msgs[2] = {
208 {
209 .addr = client->addr,
210 .flags = 0,
211 .len = 1,
212 .buf = addr,
213 }, {
214 .addr = client->addr,
215 .flags = I2C_M_NOSTART,
216 .len = mem->nr,
217 .buf = mem->data,
218 }
219 };
220
221 if (mem->loc < 8)
222 return -EINVAL;
223
224 addr[0] = mem->loc;
225
226 return i2c_transfer(client->adapter, msgs, 2) == 2 ? 0 : -EIO;
227}
228
229static int
230pcf8583_command(struct i2c_client *client, unsigned int cmd, void *arg)
231{
232 switch (cmd) {
233 case RTC_GETDATETIME:
234 return pcf8583_get_datetime(client, arg);
235
236 case RTC_SETTIME:
237 return pcf8583_set_datetime(client, arg, 0);
238
239 case RTC_SETDATETIME:
240 return pcf8583_set_datetime(client, arg, 1);
241
242 case RTC_GETCTRL:
243 return pcf8583_get_ctrl(client, arg);
244
245 case RTC_SETCTRL:
246 return pcf8583_set_ctrl(client, arg);
247
248 case MEM_READ:
249 return pcf8583_read_mem(client, arg);
250
251 case MEM_WRITE:
252 return pcf8583_write_mem(client, arg);
253
254 default:
255 return -EINVAL;
256 }
257}
258
259static struct i2c_driver pcf8583_driver = {
260 .driver = {
261 .name = "PCF8583",
262 },
263 .id = I2C_DRIVERID_PCF8583,
264 .attach_adapter = pcf8583_probe,
265 .detach_client = pcf8583_detach,
266 .command = pcf8583_command
267};
268
269static __init int pcf8583_init(void)
270{
271 return i2c_add_driver(&pcf8583_driver);
272}
273
274static __exit void pcf8583_exit(void)
275{
276 i2c_del_driver(&pcf8583_driver);
277}
278
279module_init(pcf8583_init);
280module_exit(pcf8583_exit);
281
282MODULE_AUTHOR("Russell King");
283MODULE_DESCRIPTION("PCF8583 I2C RTC driver");
284MODULE_LICENSE("GPL");
diff --git a/drivers/acorn/char/pcf8583.h b/drivers/acorn/char/pcf8583.h
deleted file mode 100644
index 847f7fdb8763..000000000000
--- a/drivers/acorn/char/pcf8583.h
+++ /dev/null
@@ -1,41 +0,0 @@
1/*
2 * linux/drivers/acorn/char/pcf8583.h
3 *
4 * Copyright (C) 2000 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10struct rtc_tm {
11 unsigned char cs;
12 unsigned char secs;
13 unsigned char mins;
14 unsigned char hours;
15 unsigned char mday;
16 unsigned char mon;
17 unsigned char year_off;
18 unsigned char wday;
19};
20
21struct mem {
22 unsigned int loc;
23 unsigned int nr;
24 unsigned char *data;
25};
26
27#define RTC_GETDATETIME 0
28#define RTC_SETTIME 1
29#define RTC_SETDATETIME 2
30#define RTC_GETCTRL 3
31#define RTC_SETCTRL 4
32#define MEM_READ 5
33#define MEM_WRITE 6
34
35#define CTRL_STOP 0x80
36#define CTRL_HOLD 0x40
37#define CTRL_32KHZ 0x00
38#define CTRL_MASK 0x08
39#define CTRL_ALARMEN 0x04
40#define CTRL_ALARM 0x02
41#define CTRL_TIMER 0x01
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 4d44a2db29dd..fb19dbb31e42 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -495,6 +495,16 @@ config I2C_VERSATILE
495 This driver can also be built as a module. If so, the module 495 This driver can also be built as a module. If so, the module
496 will be called i2c-versatile. 496 will be called i2c-versatile.
497 497
498config I2C_ACORN
499 bool "Acorn IOC/IOMD I2C bus support"
500 depends on I2C && ARCH_ACORN
501 default y
502 select I2C_ALGOBIT
503 help
504 Say yes if you want to support the I2C bus on Acorn platforms.
505
506 If you don't know, say Y.
507
498config I2C_VIA 508config I2C_VIA
499 tristate "VIA 82C586B" 509 tristate "VIA 82C586B"
500 depends on I2C && PCI && EXPERIMENTAL 510 depends on I2C && PCI && EXPERIMENTAL
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 03505aa44bbf..290b54018354 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -42,6 +42,7 @@ obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o
42obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o 42obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o
43obj-$(CONFIG_I2C_STUB) += i2c-stub.o 43obj-$(CONFIG_I2C_STUB) += i2c-stub.o
44obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o 44obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
45obj-$(CONFIG_I2C_ACORN) += i2c-acorn.o
45obj-$(CONFIG_I2C_VIA) += i2c-via.o 46obj-$(CONFIG_I2C_VIA) += i2c-via.o
46obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o 47obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o
47obj-$(CONFIG_I2C_VOODOO3) += i2c-voodoo3.o 48obj-$(CONFIG_I2C_VOODOO3) += i2c-voodoo3.o
diff --git a/drivers/i2c/busses/i2c-acorn.c b/drivers/i2c/busses/i2c-acorn.c
new file mode 100644
index 000000000000..09bd7f40b90c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-acorn.c
@@ -0,0 +1,97 @@
1/*
2 * linux/drivers/acorn/char/i2c.c
3 *
4 * Copyright (C) 2000 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * ARM IOC/IOMD i2c driver.
11 *
12 * On Acorn machines, the following i2c devices are on the bus:
13 * - PCF8583 real time clock & static RAM
14 */
15#include <linux/init.h>
16#include <linux/i2c.h>
17#include <linux/i2c-algo-bit.h>
18
19#include <asm/hardware.h>
20#include <asm/io.h>
21#include <asm/hardware/ioc.h>
22#include <asm/system.h>
23
24#define FORCE_ONES 0xdc
25#define SCL 0x02
26#define SDA 0x01
27
28/*
29 * We must preserve all non-i2c output bits in IOC_CONTROL.
30 * Note also that we need to preserve the value of SCL and
31 * SDA outputs as well (which may be different from the
32 * values read back from IOC_CONTROL).
33 */
34static u_int force_ones;
35
36static void ioc_setscl(void *data, int state)
37{
38 u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA);
39 u_int ones = force_ones;
40
41 if (state)
42 ones |= SCL;
43 else
44 ones &= ~SCL;
45
46 force_ones = ones;
47
48 ioc_writeb(ioc_control | ones, IOC_CONTROL);
49}
50
51static void ioc_setsda(void *data, int state)
52{
53 u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA);
54 u_int ones = force_ones;
55
56 if (state)
57 ones |= SDA;
58 else
59 ones &= ~SDA;
60
61 force_ones = ones;
62
63 ioc_writeb(ioc_control | ones, IOC_CONTROL);
64}
65
66static int ioc_getscl(void *data)
67{
68 return (ioc_readb(IOC_CONTROL) & SCL) != 0;
69}
70
71static int ioc_getsda(void *data)
72{
73 return (ioc_readb(IOC_CONTROL) & SDA) != 0;
74}
75
76static struct i2c_algo_bit_data ioc_data = {
77 .setsda = ioc_setsda,
78 .setscl = ioc_setscl,
79 .getsda = ioc_getsda,
80 .getscl = ioc_getscl,
81 .udelay = 80,
82 .timeout = 100
83};
84
85static struct i2c_adapter ioc_ops = {
86 .id = I2C_HW_B_IOC,
87 .algo_data = &ioc_data,
88};
89
90static int __init i2c_ioc_init(void)
91{
92 force_ones = FORCE_ONES | SCL | SDA;
93
94 return i2c_bit_add_bus(&ioc_ops);
95}
96
97__initcall(i2c_ioc_init);
generated by cgit v1.2.2 (git 2.25.0) at 2025-12-25 08:32:24 -0500