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1/* drivers/rtc/rtc-v3020.c
2 *
3 * Copyright (C) 2006 8D Technologies inc.
4 * Copyright (C) 2004 Compulab Ltd.
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 the V3020 RTC
11 *
12 * Changelog:
13 *
14 * 10-May-2006: Raphael Assenat <raph@8d.com>
15 * - Converted to platform driver
16 * - Use the generic rtc class
17 *
18 * ??-???-2004: Someone at Compulab
19 * - Initial driver creation.
20 *
21 */
22#include <linux/platform_device.h>
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/rtc.h>
26#include <linux/types.h>
27#include <linux/bcd.h>
28#include <linux/rtc-v3020.h>
29#include <linux/delay.h>
30#include <linux/gpio.h>
31#include <linux/slab.h>
32
33#include <linux/io.h>
34
35#undef DEBUG
36
37struct v3020;
38
39struct v3020_chip_ops {
40 int (*map_io)(struct v3020 *chip, struct platform_device *pdev,
41 struct v3020_platform_data *pdata);
42 void (*unmap_io)(struct v3020 *chip);
43 unsigned char (*read_bit)(struct v3020 *chip);
44 void (*write_bit)(struct v3020 *chip, unsigned char bit);
45};
46
47#define V3020_CS 0
48#define V3020_WR 1
49#define V3020_RD 2
50#define V3020_IO 3
51
52struct v3020_gpio {
53 const char *name;
54 unsigned int gpio;
55};
56
57struct v3020 {
58 /* MMIO access */
59 void __iomem *ioaddress;
60 int leftshift;
61
62 /* GPIO access */
63 struct v3020_gpio *gpio;
64
65 struct v3020_chip_ops *ops;
66
67 struct rtc_device *rtc;
68};
69
70
71static int v3020_mmio_map(struct v3020 *chip, struct platform_device *pdev,
72 struct v3020_platform_data *pdata)
73{
74 if (pdev->num_resources != 1)
75 return -EBUSY;
76
77 if (pdev->resource[0].flags != IORESOURCE_MEM)
78 return -EBUSY;
79
80 chip->leftshift = pdata->leftshift;
81 chip->ioaddress = ioremap(pdev->resource[0].start, 1);
82 if (chip->ioaddress == NULL)
83 return -EBUSY;
84
85 return 0;
86}
87
88static void v3020_mmio_unmap(struct v3020 *chip)
89{
90 iounmap(chip->ioaddress);
91}
92
93static void v3020_mmio_write_bit(struct v3020 *chip, unsigned char bit)
94{
95 writel(bit << chip->leftshift, chip->ioaddress);
96}
97
98static unsigned char v3020_mmio_read_bit(struct v3020 *chip)
99{
100 return !!(readl(chip->ioaddress) & (1 << chip->leftshift));
101}
102
103static struct v3020_chip_ops v3020_mmio_ops = {
104 .map_io = v3020_mmio_map,
105 .unmap_io = v3020_mmio_unmap,
106 .read_bit = v3020_mmio_read_bit,
107 .write_bit = v3020_mmio_write_bit,
108};
109
110static struct v3020_gpio v3020_gpio[] = {
111 { "RTC CS", 0 },
112 { "RTC WR", 0 },
113 { "RTC RD", 0 },
114 { "RTC IO", 0 },
115};
116
117static int v3020_gpio_map(struct v3020 *chip, struct platform_device *pdev,
118 struct v3020_platform_data *pdata)
119{
120 int i, err;
121
122 v3020_gpio[V3020_CS].gpio = pdata->gpio_cs;
123 v3020_gpio[V3020_WR].gpio = pdata->gpio_wr;
124 v3020_gpio[V3020_RD].gpio = pdata->gpio_rd;
125 v3020_gpio[V3020_IO].gpio = pdata->gpio_io;
126
127 for (i = 0; i < ARRAY_SIZE(v3020_gpio); i++) {
128 err = gpio_request(v3020_gpio[i].gpio, v3020_gpio[i].name);
129 if (err)
130 goto err_request;
131
132 gpio_direction_output(v3020_gpio[i].gpio, 1);
133 }
134
135 chip->gpio = v3020_gpio;
136
137 return 0;
138
139err_request:
140 while (--i >= 0)
141 gpio_free(v3020_gpio[i].gpio);
142
143 return err;
144}
145
146static void v3020_gpio_unmap(struct v3020 *chip)
147{
148 int i;
149
150 for (i = 0; i < ARRAY_SIZE(v3020_gpio); i++)
151 gpio_free(v3020_gpio[i].gpio);
152}
153
154static void v3020_gpio_write_bit(struct v3020 *chip, unsigned char bit)
155{
156 gpio_direction_output(chip->gpio[V3020_IO].gpio, bit);
157 gpio_set_value(chip->gpio[V3020_CS].gpio, 0);
158 gpio_set_value(chip->gpio[V3020_WR].gpio, 0);
159 udelay(1);
160 gpio_set_value(chip->gpio[V3020_WR].gpio, 1);
161 gpio_set_value(chip->gpio[V3020_CS].gpio, 1);
162}
163
164static unsigned char v3020_gpio_read_bit(struct v3020 *chip)
165{
166 int bit;
167
168 gpio_direction_input(chip->gpio[V3020_IO].gpio);
169 gpio_set_value(chip->gpio[V3020_CS].gpio, 0);
170 gpio_set_value(chip->gpio[V3020_RD].gpio, 0);
171 udelay(1);
172 bit = !!gpio_get_value(chip->gpio[V3020_IO].gpio);
173 udelay(1);
174 gpio_set_value(chip->gpio[V3020_RD].gpio, 1);
175 gpio_set_value(chip->gpio[V3020_CS].gpio, 1);
176
177 return bit;
178}
179
180static struct v3020_chip_ops v3020_gpio_ops = {
181 .map_io = v3020_gpio_map,
182 .unmap_io = v3020_gpio_unmap,
183 .read_bit = v3020_gpio_read_bit,
184 .write_bit = v3020_gpio_write_bit,
185};
186
187static void v3020_set_reg(struct v3020 *chip, unsigned char address,
188 unsigned char data)
189{
190 int i;
191 unsigned char tmp;
192
193 tmp = address;
194 for (i = 0; i < 4; i++) {
195 chip->ops->write_bit(chip, (tmp & 1));
196 tmp >>= 1;
197 udelay(1);
198 }
199
200 /* Commands dont have data */
201 if (!V3020_IS_COMMAND(address)) {
202 for (i = 0; i < 8; i++) {
203 chip->ops->write_bit(chip, (data & 1));
204 data >>= 1;
205 udelay(1);
206 }
207 }
208}
209
210static unsigned char v3020_get_reg(struct v3020 *chip, unsigned char address)
211{
212 unsigned int data = 0;
213 int i;
214
215 for (i = 0; i < 4; i++) {
216 chip->ops->write_bit(chip, (address & 1));
217 address >>= 1;
218 udelay(1);
219 }
220
221 for (i = 0; i < 8; i++) {
222 data >>= 1;
223 if (chip->ops->read_bit(chip))
224 data |= 0x80;
225 udelay(1);
226 }
227
228 return data;
229}
230
231static int v3020_read_time(struct device *dev, struct rtc_time *dt)
232{
233 struct v3020 *chip = dev_get_drvdata(dev);
234 int tmp;
235
236 /* Copy the current time to ram... */
237 v3020_set_reg(chip, V3020_CMD_CLOCK2RAM, 0);
238
239 /* ...and then read constant values. */
240 tmp = v3020_get_reg(chip, V3020_SECONDS);
241 dt->tm_sec = bcd2bin(tmp);
242 tmp = v3020_get_reg(chip, V3020_MINUTES);
243 dt->tm_min = bcd2bin(tmp);
244 tmp = v3020_get_reg(chip, V3020_HOURS);
245 dt->tm_hour = bcd2bin(tmp);
246 tmp = v3020_get_reg(chip, V3020_MONTH_DAY);
247 dt->tm_mday = bcd2bin(tmp);
248 tmp = v3020_get_reg(chip, V3020_MONTH);
249 dt->tm_mon = bcd2bin(tmp) - 1;
250 tmp = v3020_get_reg(chip, V3020_WEEK_DAY);
251 dt->tm_wday = bcd2bin(tmp);
252 tmp = v3020_get_reg(chip, V3020_YEAR);
253 dt->tm_year = bcd2bin(tmp)+100;
254
255 dev_dbg(dev, "\n%s : Read RTC values\n", __func__);
256 dev_dbg(dev, "tm_hour: %i\n", dt->tm_hour);
257 dev_dbg(dev, "tm_min : %i\n", dt->tm_min);
258 dev_dbg(dev, "tm_sec : %i\n", dt->tm_sec);
259 dev_dbg(dev, "tm_year: %i\n", dt->tm_year);
260 dev_dbg(dev, "tm_mon : %i\n", dt->tm_mon);
261 dev_dbg(dev, "tm_mday: %i\n", dt->tm_mday);
262 dev_dbg(dev, "tm_wday: %i\n", dt->tm_wday);
263
264 return 0;
265}
266
267
268static int v3020_set_time(struct device *dev, struct rtc_time *dt)
269{
270 struct v3020 *chip = dev_get_drvdata(dev);
271
272 dev_dbg(dev, "\n%s : Setting RTC values\n", __func__);
273 dev_dbg(dev, "tm_sec : %i\n", dt->tm_sec);
274 dev_dbg(dev, "tm_min : %i\n", dt->tm_min);
275 dev_dbg(dev, "tm_hour: %i\n", dt->tm_hour);
276 dev_dbg(dev, "tm_mday: %i\n", dt->tm_mday);
277 dev_dbg(dev, "tm_wday: %i\n", dt->tm_wday);
278 dev_dbg(dev, "tm_year: %i\n", dt->tm_year);
279
280 /* Write all the values to ram... */
281 v3020_set_reg(chip, V3020_SECONDS, bin2bcd(dt->tm_sec));
282 v3020_set_reg(chip, V3020_MINUTES, bin2bcd(dt->tm_min));
283 v3020_set_reg(chip, V3020_HOURS, bin2bcd(dt->tm_hour));
284 v3020_set_reg(chip, V3020_MONTH_DAY, bin2bcd(dt->tm_mday));
285 v3020_set_reg(chip, V3020_MONTH, bin2bcd(dt->tm_mon + 1));
286 v3020_set_reg(chip, V3020_WEEK_DAY, bin2bcd(dt->tm_wday));
287 v3020_set_reg(chip, V3020_YEAR, bin2bcd(dt->tm_year % 100));
288
289 /* ...and set the clock. */
290 v3020_set_reg(chip, V3020_CMD_RAM2CLOCK, 0);
291
292 /* Compulab used this delay here. I dont know why,
293 * the datasheet does not specify a delay. */
294 /*mdelay(5);*/
295
296 return 0;
297}
298
299static const struct rtc_class_ops v3020_rtc_ops = {
300 .read_time = v3020_read_time,
301 .set_time = v3020_set_time,
302};
303
304static int rtc_probe(struct platform_device *pdev)
305{
306 struct v3020_platform_data *pdata = pdev->dev.platform_data;
307 struct v3020 *chip;
308 int retval = -EBUSY;
309 int i;
310 int temp;
311
312 chip = kzalloc(sizeof *chip, GFP_KERNEL);
313 if (!chip)
314 return -ENOMEM;
315
316 if (pdata->use_gpio)
317 chip->ops = &v3020_gpio_ops;
318 else
319 chip->ops = &v3020_mmio_ops;
320
321 retval = chip->ops->map_io(chip, pdev, pdata);
322 if (retval)
323 goto err_chip;
324
325 /* Make sure the v3020 expects a communication cycle
326 * by reading 8 times */
327 for (i = 0; i < 8; i++)
328 temp = chip->ops->read_bit(chip);
329
330 /* Test chip by doing a write/read sequence
331 * to the chip ram */
332 v3020_set_reg(chip, V3020_SECONDS, 0x33);
333 if (v3020_get_reg(chip, V3020_SECONDS) != 0x33) {
334 retval = -ENODEV;
335 goto err_io;
336 }
337
338 /* Make sure frequency measurement mode, test modes, and lock
339 * are all disabled */
340 v3020_set_reg(chip, V3020_STATUS_0, 0x0);
341
342 if (pdata->use_gpio)
343 dev_info(&pdev->dev, "Chip available at GPIOs "
344 "%d, %d, %d, %d\n",
345 chip->gpio[V3020_CS].gpio, chip->gpio[V3020_WR].gpio,
346 chip->gpio[V3020_RD].gpio, chip->gpio[V3020_IO].gpio);
347 else
348 dev_info(&pdev->dev, "Chip available at "
349 "physical address 0x%llx,"
350 "data connected to D%d\n",
351 (unsigned long long)pdev->resource[0].start,
352 chip->leftshift);
353
354 platform_set_drvdata(pdev, chip);
355
356 chip->rtc = rtc_device_register("v3020",
357 &pdev->dev, &v3020_rtc_ops, THIS_MODULE);
358 if (IS_ERR(chip->rtc)) {
359 retval = PTR_ERR(chip->rtc);
360 goto err_io;
361 }
362
363 return 0;
364
365err_io:
366 chip->ops->unmap_io(chip);
367err_chip:
368 kfree(chip);
369
370 return retval;
371}
372
373static int rtc_remove(struct platform_device *dev)
374{
375 struct v3020 *chip = platform_get_drvdata(dev);
376 struct rtc_device *rtc = chip->rtc;
377
378 if (rtc)
379 rtc_device_unregister(rtc);
380
381 chip->ops->unmap_io(chip);
382 kfree(chip);
383
384 return 0;
385}
386
387static struct platform_driver rtc_device_driver = {
388 .probe = rtc_probe,
389 .remove = rtc_remove,
390 .driver = {
391 .name = "v3020",
392 .owner = THIS_MODULE,
393 },
394};
395
396static __init int v3020_init(void)
397{
398 return platform_driver_register(&rtc_device_driver);
399}
400
401static __exit void v3020_exit(void)
402{
403 platform_driver_unregister(&rtc_device_driver);
404}
405
406module_init(v3020_init);
407module_exit(v3020_exit);
408
409MODULE_DESCRIPTION("V3020 RTC");
410MODULE_AUTHOR("Raphael Assenat");
411MODULE_LICENSE("GPL");
412MODULE_ALIAS("platform:v3020");
1// SPDX-License-Identifier: GPL-2.0-only
2/* drivers/rtc/rtc-v3020.c
3 *
4 * Copyright (C) 2006 8D Technologies inc.
5 * Copyright (C) 2004 Compulab Ltd.
6 *
7 * Driver for the V3020 RTC
8 *
9 * Changelog:
10 *
11 * 10-May-2006: Raphael Assenat <raph@8d.com>
12 * - Converted to platform driver
13 * - Use the generic rtc class
14 *
15 * ??-???-2004: Someone at Compulab
16 * - Initial driver creation.
17 */
18#include <linux/platform_device.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/rtc.h>
22#include <linux/types.h>
23#include <linux/bcd.h>
24#include <linux/platform_data/rtc-v3020.h>
25#include <linux/delay.h>
26#include <linux/gpio.h>
27#include <linux/slab.h>
28
29#include <linux/io.h>
30
31#undef DEBUG
32
33struct v3020;
34
35struct v3020_chip_ops {
36 int (*map_io)(struct v3020 *chip, struct platform_device *pdev,
37 struct v3020_platform_data *pdata);
38 void (*unmap_io)(struct v3020 *chip);
39 unsigned char (*read_bit)(struct v3020 *chip);
40 void (*write_bit)(struct v3020 *chip, unsigned char bit);
41};
42
43#define V3020_CS 0
44#define V3020_WR 1
45#define V3020_RD 2
46#define V3020_IO 3
47
48struct v3020 {
49 /* MMIO access */
50 void __iomem *ioaddress;
51 int leftshift;
52
53 /* GPIO access */
54 struct gpio *gpio;
55
56 const struct v3020_chip_ops *ops;
57
58 struct rtc_device *rtc;
59};
60
61
62static int v3020_mmio_map(struct v3020 *chip, struct platform_device *pdev,
63 struct v3020_platform_data *pdata)
64{
65 if (pdev->num_resources != 1)
66 return -EBUSY;
67
68 if (pdev->resource[0].flags != IORESOURCE_MEM)
69 return -EBUSY;
70
71 chip->leftshift = pdata->leftshift;
72 chip->ioaddress = ioremap(pdev->resource[0].start, 1);
73 if (chip->ioaddress == NULL)
74 return -EBUSY;
75
76 return 0;
77}
78
79static void v3020_mmio_unmap(struct v3020 *chip)
80{
81 iounmap(chip->ioaddress);
82}
83
84static void v3020_mmio_write_bit(struct v3020 *chip, unsigned char bit)
85{
86 writel(bit << chip->leftshift, chip->ioaddress);
87}
88
89static unsigned char v3020_mmio_read_bit(struct v3020 *chip)
90{
91 return !!(readl(chip->ioaddress) & (1 << chip->leftshift));
92}
93
94static const struct v3020_chip_ops v3020_mmio_ops = {
95 .map_io = v3020_mmio_map,
96 .unmap_io = v3020_mmio_unmap,
97 .read_bit = v3020_mmio_read_bit,
98 .write_bit = v3020_mmio_write_bit,
99};
100
101static struct gpio v3020_gpio[] = {
102 { 0, GPIOF_OUT_INIT_HIGH, "RTC CS"},
103 { 0, GPIOF_OUT_INIT_HIGH, "RTC WR"},
104 { 0, GPIOF_OUT_INIT_HIGH, "RTC RD"},
105 { 0, GPIOF_OUT_INIT_HIGH, "RTC IO"},
106};
107
108static int v3020_gpio_map(struct v3020 *chip, struct platform_device *pdev,
109 struct v3020_platform_data *pdata)
110{
111 int err;
112
113 v3020_gpio[V3020_CS].gpio = pdata->gpio_cs;
114 v3020_gpio[V3020_WR].gpio = pdata->gpio_wr;
115 v3020_gpio[V3020_RD].gpio = pdata->gpio_rd;
116 v3020_gpio[V3020_IO].gpio = pdata->gpio_io;
117
118 err = gpio_request_array(v3020_gpio, ARRAY_SIZE(v3020_gpio));
119
120 if (!err)
121 chip->gpio = v3020_gpio;
122
123 return err;
124}
125
126static void v3020_gpio_unmap(struct v3020 *chip)
127{
128 gpio_free_array(v3020_gpio, ARRAY_SIZE(v3020_gpio));
129}
130
131static void v3020_gpio_write_bit(struct v3020 *chip, unsigned char bit)
132{
133 gpio_direction_output(chip->gpio[V3020_IO].gpio, bit);
134 gpio_set_value(chip->gpio[V3020_CS].gpio, 0);
135 gpio_set_value(chip->gpio[V3020_WR].gpio, 0);
136 udelay(1);
137 gpio_set_value(chip->gpio[V3020_WR].gpio, 1);
138 gpio_set_value(chip->gpio[V3020_CS].gpio, 1);
139}
140
141static unsigned char v3020_gpio_read_bit(struct v3020 *chip)
142{
143 int bit;
144
145 gpio_direction_input(chip->gpio[V3020_IO].gpio);
146 gpio_set_value(chip->gpio[V3020_CS].gpio, 0);
147 gpio_set_value(chip->gpio[V3020_RD].gpio, 0);
148 udelay(1);
149 bit = !!gpio_get_value(chip->gpio[V3020_IO].gpio);
150 udelay(1);
151 gpio_set_value(chip->gpio[V3020_RD].gpio, 1);
152 gpio_set_value(chip->gpio[V3020_CS].gpio, 1);
153
154 return bit;
155}
156
157static const struct v3020_chip_ops v3020_gpio_ops = {
158 .map_io = v3020_gpio_map,
159 .unmap_io = v3020_gpio_unmap,
160 .read_bit = v3020_gpio_read_bit,
161 .write_bit = v3020_gpio_write_bit,
162};
163
164static void v3020_set_reg(struct v3020 *chip, unsigned char address,
165 unsigned char data)
166{
167 int i;
168 unsigned char tmp;
169
170 tmp = address;
171 for (i = 0; i < 4; i++) {
172 chip->ops->write_bit(chip, (tmp & 1));
173 tmp >>= 1;
174 udelay(1);
175 }
176
177 /* Commands dont have data */
178 if (!V3020_IS_COMMAND(address)) {
179 for (i = 0; i < 8; i++) {
180 chip->ops->write_bit(chip, (data & 1));
181 data >>= 1;
182 udelay(1);
183 }
184 }
185}
186
187static unsigned char v3020_get_reg(struct v3020 *chip, unsigned char address)
188{
189 unsigned int data = 0;
190 int i;
191
192 for (i = 0; i < 4; i++) {
193 chip->ops->write_bit(chip, (address & 1));
194 address >>= 1;
195 udelay(1);
196 }
197
198 for (i = 0; i < 8; i++) {
199 data >>= 1;
200 if (chip->ops->read_bit(chip))
201 data |= 0x80;
202 udelay(1);
203 }
204
205 return data;
206}
207
208static int v3020_read_time(struct device *dev, struct rtc_time *dt)
209{
210 struct v3020 *chip = dev_get_drvdata(dev);
211 int tmp;
212
213 /* Copy the current time to ram... */
214 v3020_set_reg(chip, V3020_CMD_CLOCK2RAM, 0);
215
216 /* ...and then read constant values. */
217 tmp = v3020_get_reg(chip, V3020_SECONDS);
218 dt->tm_sec = bcd2bin(tmp);
219 tmp = v3020_get_reg(chip, V3020_MINUTES);
220 dt->tm_min = bcd2bin(tmp);
221 tmp = v3020_get_reg(chip, V3020_HOURS);
222 dt->tm_hour = bcd2bin(tmp);
223 tmp = v3020_get_reg(chip, V3020_MONTH_DAY);
224 dt->tm_mday = bcd2bin(tmp);
225 tmp = v3020_get_reg(chip, V3020_MONTH);
226 dt->tm_mon = bcd2bin(tmp) - 1;
227 tmp = v3020_get_reg(chip, V3020_WEEK_DAY);
228 dt->tm_wday = bcd2bin(tmp);
229 tmp = v3020_get_reg(chip, V3020_YEAR);
230 dt->tm_year = bcd2bin(tmp)+100;
231
232 dev_dbg(dev, "\n%s : Read RTC values\n", __func__);
233 dev_dbg(dev, "tm_hour: %i\n", dt->tm_hour);
234 dev_dbg(dev, "tm_min : %i\n", dt->tm_min);
235 dev_dbg(dev, "tm_sec : %i\n", dt->tm_sec);
236 dev_dbg(dev, "tm_year: %i\n", dt->tm_year);
237 dev_dbg(dev, "tm_mon : %i\n", dt->tm_mon);
238 dev_dbg(dev, "tm_mday: %i\n", dt->tm_mday);
239 dev_dbg(dev, "tm_wday: %i\n", dt->tm_wday);
240
241 return 0;
242}
243
244
245static int v3020_set_time(struct device *dev, struct rtc_time *dt)
246{
247 struct v3020 *chip = dev_get_drvdata(dev);
248
249 dev_dbg(dev, "\n%s : Setting RTC values\n", __func__);
250 dev_dbg(dev, "tm_sec : %i\n", dt->tm_sec);
251 dev_dbg(dev, "tm_min : %i\n", dt->tm_min);
252 dev_dbg(dev, "tm_hour: %i\n", dt->tm_hour);
253 dev_dbg(dev, "tm_mday: %i\n", dt->tm_mday);
254 dev_dbg(dev, "tm_wday: %i\n", dt->tm_wday);
255 dev_dbg(dev, "tm_year: %i\n", dt->tm_year);
256
257 /* Write all the values to ram... */
258 v3020_set_reg(chip, V3020_SECONDS, bin2bcd(dt->tm_sec));
259 v3020_set_reg(chip, V3020_MINUTES, bin2bcd(dt->tm_min));
260 v3020_set_reg(chip, V3020_HOURS, bin2bcd(dt->tm_hour));
261 v3020_set_reg(chip, V3020_MONTH_DAY, bin2bcd(dt->tm_mday));
262 v3020_set_reg(chip, V3020_MONTH, bin2bcd(dt->tm_mon + 1));
263 v3020_set_reg(chip, V3020_WEEK_DAY, bin2bcd(dt->tm_wday));
264 v3020_set_reg(chip, V3020_YEAR, bin2bcd(dt->tm_year % 100));
265
266 /* ...and set the clock. */
267 v3020_set_reg(chip, V3020_CMD_RAM2CLOCK, 0);
268
269 /* Compulab used this delay here. I dont know why,
270 * the datasheet does not specify a delay. */
271 /*mdelay(5);*/
272
273 return 0;
274}
275
276static const struct rtc_class_ops v3020_rtc_ops = {
277 .read_time = v3020_read_time,
278 .set_time = v3020_set_time,
279};
280
281static int rtc_probe(struct platform_device *pdev)
282{
283 struct v3020_platform_data *pdata = dev_get_platdata(&pdev->dev);
284 struct v3020 *chip;
285 int retval = -EBUSY;
286 int i;
287 int temp;
288
289 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
290 if (!chip)
291 return -ENOMEM;
292
293 if (pdata->use_gpio)
294 chip->ops = &v3020_gpio_ops;
295 else
296 chip->ops = &v3020_mmio_ops;
297
298 retval = chip->ops->map_io(chip, pdev, pdata);
299 if (retval)
300 return retval;
301
302 /* Make sure the v3020 expects a communication cycle
303 * by reading 8 times */
304 for (i = 0; i < 8; i++)
305 temp = chip->ops->read_bit(chip);
306
307 /* Test chip by doing a write/read sequence
308 * to the chip ram */
309 v3020_set_reg(chip, V3020_SECONDS, 0x33);
310 if (v3020_get_reg(chip, V3020_SECONDS) != 0x33) {
311 retval = -ENODEV;
312 goto err_io;
313 }
314
315 /* Make sure frequency measurement mode, test modes, and lock
316 * are all disabled */
317 v3020_set_reg(chip, V3020_STATUS_0, 0x0);
318
319 if (pdata->use_gpio)
320 dev_info(&pdev->dev, "Chip available at GPIOs "
321 "%d, %d, %d, %d\n",
322 chip->gpio[V3020_CS].gpio, chip->gpio[V3020_WR].gpio,
323 chip->gpio[V3020_RD].gpio, chip->gpio[V3020_IO].gpio);
324 else
325 dev_info(&pdev->dev, "Chip available at "
326 "physical address 0x%llx,"
327 "data connected to D%d\n",
328 (unsigned long long)pdev->resource[0].start,
329 chip->leftshift);
330
331 platform_set_drvdata(pdev, chip);
332
333 chip->rtc = devm_rtc_device_register(&pdev->dev, "v3020",
334 &v3020_rtc_ops, THIS_MODULE);
335 if (IS_ERR(chip->rtc)) {
336 retval = PTR_ERR(chip->rtc);
337 goto err_io;
338 }
339
340 return 0;
341
342err_io:
343 chip->ops->unmap_io(chip);
344
345 return retval;
346}
347
348static int rtc_remove(struct platform_device *dev)
349{
350 struct v3020 *chip = platform_get_drvdata(dev);
351
352 chip->ops->unmap_io(chip);
353
354 return 0;
355}
356
357static struct platform_driver rtc_device_driver = {
358 .probe = rtc_probe,
359 .remove = rtc_remove,
360 .driver = {
361 .name = "v3020",
362 },
363};
364
365module_platform_driver(rtc_device_driver);
366
367MODULE_DESCRIPTION("V3020 RTC");
368MODULE_AUTHOR("Raphael Assenat");
369MODULE_LICENSE("GPL");
370MODULE_ALIAS("platform:v3020");