Root/target/linux/sibyte/patches-3.3/103-m41t80_smbus.patch

1--- a/drivers/rtc/rtc-m41t80.c
2+++ b/drivers/rtc/rtc-m41t80.c
3@@ -6,6 +6,7 @@
4  * Based on m41t00.c by Mark A. Greer <mgreer@mvista.com>
5  *
6  * 2006 (c) mycable GmbH
7+ * Copyright (c) 2008 Maciej W. Rozycki
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11@@ -38,6 +39,8 @@
12 #define M41T80_REG_DAY 5
13 #define M41T80_REG_MON 6
14 #define M41T80_REG_YEAR 7
15+#define M41T80_REG_CONTROL 8
16+#define M41T80_REG_WATCHDOG 9
17 #define M41T80_REG_ALARM_MON 0xa
18 #define M41T80_REG_ALARM_DAY 0xb
19 #define M41T80_REG_ALARM_HOUR 0xc
20@@ -66,7 +69,7 @@
21 #define M41T80_FEATURE_WD (1 << 3) /* Extra watchdog resolution */
22 #define M41T80_FEATURE_SQ_ALT (1 << 4) /* RSx bits are in reg 4 */
23 
24-#define DRV_VERSION "0.05"
25+#define DRV_VERSION "0.06"
26 
27 static DEFINE_MUTEX(m41t80_rtc_mutex);
28 static const struct i2c_device_id m41t80_id[] = {
29@@ -89,31 +92,88 @@ struct m41t80_data {
30     struct rtc_device *rtc;
31 };
32 
33-static int m41t80_get_datetime(struct i2c_client *client,
34- struct rtc_time *tm)
35+
36+static int m41t80_write_block_data(struct i2c_client *client,
37+ u8 reg, u8 num, u8 *buf)
38 {
39- u8 buf[M41T80_DATETIME_REG_SIZE], dt_addr[1] = { M41T80_REG_SEC };
40- struct i2c_msg msgs[] = {
41- {
42- .addr = client->addr,
43- .flags = 0,
44- .len = 1,
45- .buf = dt_addr,
46- },
47- {
48- .addr = client->addr,
49- .flags = I2C_M_RD,
50- .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC,
51- .buf = buf + M41T80_REG_SEC,
52- },
53- };
54+ int i, rc;
55 
56- if (i2c_transfer(client->adapter, msgs, 2) < 0) {
57- dev_err(&client->dev, "read error\n");
58- return -EIO;
59+ if (i2c_check_functionality(client->adapter,
60+ I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
61+ i = i2c_smbus_write_i2c_block_data(client, reg, num, buf);
62+ } else {
63+ for (i = 0; i < num; i++) {
64+ rc = i2c_smbus_write_byte_data(client, reg + i,
65+ buf[i]);
66+ if (rc < 0) {
67+ i = rc;
68+ goto out;
69+ }
70+ }
71     }
72+out:
73+ return i;
74+}
75+
76+static int m41t80_read_block_data(struct i2c_client *client,
77+ u8 reg, u8 num, u8 *buf)
78+{
79+ int i, rc;
80+
81+ if (i2c_check_functionality(client->adapter,
82+ I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
83+ i = i2c_smbus_read_i2c_block_data(client, reg, num, buf);
84+ } else {
85+ for (i = 0; i < num; i++) {
86+ rc = i2c_smbus_read_byte_data(client, reg + i);
87+ if (rc < 0) {
88+ i = rc;
89+ goto out;
90+ }
91+ buf[i] = rc;
92+ }
93+ }
94+out:
95+ return i;
96+}
97+
98+static int m41t80_get_datetime(struct i2c_client *client, struct rtc_time *tm)
99+{
100+ u8 buf[M41T80_DATETIME_REG_SIZE];
101+ int loops = 2;
102+ int sec0, sec1;
103+
104+ /*
105+ * Time registers are latched by this chip if an I2C block
106+ * transfer is used, but with SMBus-style byte accesses
107+ * this is not the case, so check seconds for a wraparound.
108+ */
109+ do {
110+ if (m41t80_read_block_data(client, M41T80_REG_SEC,
111+ M41T80_DATETIME_REG_SIZE -
112+ M41T80_REG_SEC,
113+ buf + M41T80_REG_SEC) < 0) {
114+ dev_err(&client->dev, "read error\n");
115+ return -EIO;
116+ }
117+ if (i2c_check_functionality(client->adapter,
118+ I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
119+ sec1 = buf[M41T80_REG_SEC];
120+ break;
121+ }
122+
123+ sec0 = buf[M41T80_REG_SEC];
124+ sec1 = i2c_smbus_read_byte_data(client, M41T80_REG_SEC);
125+ if (sec1 < 0) {
126+ dev_err(&client->dev, "read error\n");
127+ return -EIO;
128+ }
129+
130+ sec0 = bcd2bin(sec0 & 0x7f);
131+ sec1 = bcd2bin(sec1 & 0x7f);
132+ } while (sec1 < sec0 && --loops);
133 
134- tm->tm_sec = bcd2bin(buf[M41T80_REG_SEC] & 0x7f);
135+ tm->tm_sec = sec1;
136     tm->tm_min = bcd2bin(buf[M41T80_REG_MIN] & 0x7f);
137     tm->tm_hour = bcd2bin(buf[M41T80_REG_HOUR] & 0x3f);
138     tm->tm_mday = bcd2bin(buf[M41T80_REG_DAY] & 0x3f);
139@@ -128,39 +188,16 @@ static int m41t80_get_datetime(struct i2
140 /* Sets the given date and time to the real time clock. */
141 static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm)
142 {
143- u8 wbuf[1 + M41T80_DATETIME_REG_SIZE];
144- u8 *buf = &wbuf[1];
145- u8 dt_addr[1] = { M41T80_REG_SEC };
146- struct i2c_msg msgs_in[] = {
147- {
148- .addr = client->addr,
149- .flags = 0,
150- .len = 1,
151- .buf = dt_addr,
152- },
153- {
154- .addr = client->addr,
155- .flags = I2C_M_RD,
156- .len = M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC,
157- .buf = buf + M41T80_REG_SEC,
158- },
159- };
160- struct i2c_msg msgs[] = {
161- {
162- .addr = client->addr,
163- .flags = 0,
164- .len = 1 + M41T80_DATETIME_REG_SIZE,
165- .buf = wbuf,
166- },
167- };
168+ u8 buf[M41T80_DATETIME_REG_SIZE];
169 
170     /* Read current reg values into buf[1..7] */
171- if (i2c_transfer(client->adapter, msgs_in, 2) < 0) {
172+ if (m41t80_read_block_data(client, M41T80_REG_SEC,
173+ M41T80_DATETIME_REG_SIZE - M41T80_REG_SEC,
174+ buf + M41T80_REG_SEC) < 0) {
175         dev_err(&client->dev, "read error\n");
176         return -EIO;
177     }
178 
179- wbuf[0] = 0; /* offset into rtc's regs */
180     /* Merge time-data and register flags into buf[0..7] */
181     buf[M41T80_REG_SSEC] = 0;
182     buf[M41T80_REG_SEC] =
183@@ -178,7 +215,8 @@ static int m41t80_set_datetime(struct i2
184     /* assume 20YY not 19YY */
185     buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year % 100);
186 
187- if (i2c_transfer(client->adapter, msgs, 1) != 1) {
188+ if (m41t80_write_block_data(client, M41T80_REG_SSEC,
189+ M41T80_DATETIME_REG_SIZE, buf) < 0) {
190         dev_err(&client->dev, "write error\n");
191         return -EIO;
192     }
193@@ -238,34 +276,11 @@ err:
194 static int m41t80_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *t)
195 {
196     struct i2c_client *client = to_i2c_client(dev);
197- u8 wbuf[1 + M41T80_ALARM_REG_SIZE];
198- u8 *buf = &wbuf[1];
199+ u8 buf[M41T80_ALARM_REG_SIZE];
200     u8 *reg = buf - M41T80_REG_ALARM_MON;
201- u8 dt_addr[1] = { M41T80_REG_ALARM_MON };
202- struct i2c_msg msgs_in[] = {
203- {
204- .addr = client->addr,
205- .flags = 0,
206- .len = 1,
207- .buf = dt_addr,
208- },
209- {
210- .addr = client->addr,
211- .flags = I2C_M_RD,
212- .len = M41T80_ALARM_REG_SIZE,
213- .buf = buf,
214- },
215- };
216- struct i2c_msg msgs[] = {
217- {
218- .addr = client->addr,
219- .flags = 0,
220- .len = 1 + M41T80_ALARM_REG_SIZE,
221- .buf = wbuf,
222- },
223- };
224 
225- if (i2c_transfer(client->adapter, msgs_in, 2) < 0) {
226+ if (m41t80_read_block_data(client, M41T80_REG_ALARM_MON,
227+ M41T80_ALARM_REG_SIZE, buf) < 0) {
228         dev_err(&client->dev, "read error\n");
229         return -EIO;
230     }
231@@ -275,7 +290,6 @@ static int m41t80_rtc_set_alarm(struct d
232     reg[M41T80_REG_ALARM_MIN] = 0;
233     reg[M41T80_REG_ALARM_SEC] = 0;
234 
235- wbuf[0] = M41T80_REG_ALARM_MON; /* offset into rtc's regs */
236     reg[M41T80_REG_ALARM_SEC] |= t->time.tm_sec >= 0 ?
237         bin2bcd(t->time.tm_sec) : 0x80;
238     reg[M41T80_REG_ALARM_MIN] |= t->time.tm_min >= 0 ?
239@@ -289,7 +303,8 @@ static int m41t80_rtc_set_alarm(struct d
240     else
241         reg[M41T80_REG_ALARM_DAY] |= 0x40;
242 
243- if (i2c_transfer(client->adapter, msgs, 1) != 1) {
244+ if (m41t80_write_block_data(client, M41T80_REG_ALARM_MON,
245+ M41T80_ALARM_REG_SIZE, buf) < 0) {
246         dev_err(&client->dev, "write error\n");
247         return -EIO;
248     }
249@@ -309,24 +324,10 @@ static int m41t80_rtc_read_alarm(struct
250 {
251     struct i2c_client *client = to_i2c_client(dev);
252     u8 buf[M41T80_ALARM_REG_SIZE + 1]; /* all alarm regs and flags */
253- u8 dt_addr[1] = { M41T80_REG_ALARM_MON };
254     u8 *reg = buf - M41T80_REG_ALARM_MON;
255- struct i2c_msg msgs[] = {
256- {
257- .addr = client->addr,
258- .flags = 0,
259- .len = 1,
260- .buf = dt_addr,
261- },
262- {
263- .addr = client->addr,
264- .flags = I2C_M_RD,
265- .len = M41T80_ALARM_REG_SIZE + 1,
266- .buf = buf,
267- },
268- };
269 
270- if (i2c_transfer(client->adapter, msgs, 2) < 0) {
271+ if (m41t80_read_block_data(client, M41T80_REG_ALARM_MON,
272+ M41T80_ALARM_REG_SIZE + 1, buf) < 0) {
273         dev_err(&client->dev, "read error\n");
274         return -EIO;
275     }
276@@ -508,26 +509,16 @@ static int boot_flag;
277  */
278 static void wdt_ping(void)
279 {
280- unsigned char i2c_data[2];
281- struct i2c_msg msgs1[1] = {
282- {
283- .addr = save_client->addr,
284- .flags = 0,
285- .len = 2,
286- .buf = i2c_data,
287- },
288- };
289- struct m41t80_data *clientdata = i2c_get_clientdata(save_client);
290+ u8 wdt = 0x80; /* WDS = 1 (0x80) */
291 
292- i2c_data[0] = 0x09; /* watchdog register */
293+ struct m41t80_data *clientdata = i2c_get_clientdata(save_client);
294 
295     if (wdt_margin > 31)
296- i2c_data[1] = (wdt_margin & 0xFC) | 0x83; /* resolution = 4s */
297+ /* mulitplier = WD_TIMO / 4, resolution = 4s (0x3) */
298+ wdt |= (wdt_margin & 0xfc) | 0x3;
299     else
300- /*
301- * WDS = 1 (0x80), mulitplier = WD_TIMO, resolution = 1s (0x02)
302- */
303- i2c_data[1] = wdt_margin<<2 | 0x82;
304+ /* mulitplier = WD_TIMO, resolution = 1s (0x2) */
305+ wdt |= wdt_margin << 2 | 0x2;
306 
307     /*
308      * M41T65 has three bits for watchdog resolution. Don't set bit 7, as
309@@ -536,7 +527,7 @@ static void wdt_ping(void)
310     if (clientdata->features & M41T80_FEATURE_WD)
311         i2c_data[1] &= ~M41T80_WATCHDOG_RB2;
312 
313- i2c_transfer(save_client->adapter, msgs1, 1);
314+ i2c_smbus_write_byte_data(save_client, M41T80_REG_WATCHDOG, wdt);
315 }
316 
317 /**
318@@ -546,36 +537,8 @@ static void wdt_ping(void)
319  */
320 static void wdt_disable(void)
321 {
322- unsigned char i2c_data[2], i2c_buf[0x10];
323- struct i2c_msg msgs0[2] = {
324- {
325- .addr = save_client->addr,
326- .flags = 0,
327- .len = 1,
328- .buf = i2c_data,
329- },
330- {
331- .addr = save_client->addr,
332- .flags = I2C_M_RD,
333- .len = 1,
334- .buf = i2c_buf,
335- },
336- };
337- struct i2c_msg msgs1[1] = {
338- {
339- .addr = save_client->addr,
340- .flags = 0,
341- .len = 2,
342- .buf = i2c_data,
343- },
344- };
345-
346- i2c_data[0] = 0x09;
347- i2c_transfer(save_client->adapter, msgs0, 2);
348-
349- i2c_data[0] = 0x09;
350- i2c_data[1] = 0x00;
351- i2c_transfer(save_client->adapter, msgs1, 1);
352+ i2c_smbus_read_byte_data(save_client, M41T80_REG_WATCHDOG);
353+ i2c_smbus_write_byte_data(save_client, M41T80_REG_WATCHDOG, 0);
354 }
355 
356 /**
357@@ -777,8 +740,8 @@ static int m41t80_probe(struct i2c_clien
358     struct rtc_time tm;
359     struct m41t80_data *clientdata = NULL;
360 
361- if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C
362- | I2C_FUNC_SMBUS_BYTE_DATA)) {
363+ if (!i2c_check_functionality(client->adapter,
364+ I2C_FUNC_SMBUS_BYTE_DATA)) {
365         rc = -ENODEV;
366         goto exit;
367     }
368

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