xref: /openbmc/linux/include/linux/rtc/ds1685.h (revision b664e06d)
1 /*
2  * Definitions for the registers, addresses, and platform data of the
3  * DS1685/DS1687-series RTC chips.
4  *
5  * This Driver also works for the DS17X85/DS17X87 RTC chips.  Functionally
6  * similar to the DS1685/DS1687, they support a few extra features which
7  * include larger, battery-backed NV-SRAM, burst-mode access, and an RTC
8  * write counter.
9  *
10  * Copyright (C) 2011-2014 Joshua Kinard <kumba@gentoo.org>.
11  * Copyright (C) 2009 Matthias Fuchs <matthias.fuchs@esd-electronics.com>.
12  *
13  * References:
14  *    DS1685/DS1687 3V/5V Real-Time Clocks, 19-5215, Rev 4/10.
15  *    DS17x85/DS17x87 3V/5V Real-Time Clocks, 19-5222, Rev 4/10.
16  *    DS1689/DS1693 3V/5V Serialized Real-Time Clocks, Rev 112105.
17  *    Application Note 90, Using the Multiplex Bus RTC Extended Features.
18  *
19  * This program is free software; you can redistribute it and/or modify
20  * it under the terms of the GNU General Public License version 2 as
21  * published by the Free Software Foundation.
22  */
23 
24 #ifndef _LINUX_RTC_DS1685_H_
25 #define _LINUX_RTC_DS1685_H_
26 
27 #include <linux/rtc.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 
31 /**
32  * struct ds1685_priv - DS1685 private data structure.
33  * @dev: pointer to the rtc_device structure.
34  * @regs: iomapped base address pointer of the RTC registers.
35  * @regstep: padding/step size between registers (optional).
36  * @baseaddr: base address of the RTC device.
37  * @size: resource size.
38  * @lock: private lock variable for spin locking/unlocking.
39  * @work: private workqueue.
40  * @irq: IRQ number assigned to the RTC device.
41  * @prepare_poweroff: pointer to platform pre-poweroff function.
42  * @wake_alarm: pointer to platform wake alarm function.
43  * @post_ram_clear: pointer to platform post ram-clear function.
44  */
45 struct ds1685_priv {
46 	struct rtc_device *dev;
47 	void __iomem *regs;
48 	u32 regstep;
49 	resource_size_t baseaddr;
50 	size_t size;
51 	int irq_num;
52 	bool bcd_mode;
53 	bool no_irq;
54 	bool uie_unsupported;
55 	bool alloc_io_resources;
56 	u8 (*read)(struct ds1685_priv *, int);
57 	void (*write)(struct ds1685_priv *, int, u8);
58 	void (*prepare_poweroff)(void);
59 	void (*wake_alarm)(void);
60 	void (*post_ram_clear)(void);
61 };
62 
63 
64 /**
65  * struct ds1685_rtc_platform_data - platform data structure.
66  * @plat_prepare_poweroff: platform-specific pre-poweroff function.
67  * @plat_wake_alarm: platform-specific wake alarm function.
68  * @plat_post_ram_clear: platform-specific post ram-clear function.
69  *
70  * If your platform needs to use a custom padding/step size between
71  * registers, or uses one or more of the extended interrupts and needs special
72  * handling, then include this header file in your platform definition and
73  * set regstep and the plat_* pointers as appropriate.
74  */
75 struct ds1685_rtc_platform_data {
76 	const u32 regstep;
77 	const bool bcd_mode;
78 	const bool no_irq;
79 	const bool uie_unsupported;
80 	const bool alloc_io_resources;
81 	u8 (*plat_read)(struct ds1685_priv *, int);
82 	void (*plat_write)(struct ds1685_priv *, int, u8);
83 	void (*plat_prepare_poweroff)(void);
84 	void (*plat_wake_alarm)(void);
85 	void (*plat_post_ram_clear)(void);
86 };
87 
88 
89 /*
90  * Time Registers.
91  */
92 #define RTC_SECS		0x00	/* Seconds 00-59 */
93 #define RTC_SECS_ALARM		0x01	/* Alarm Seconds 00-59 */
94 #define RTC_MINS		0x02	/* Minutes 00-59 */
95 #define RTC_MINS_ALARM		0x03	/* Alarm Minutes 00-59 */
96 #define RTC_HRS			0x04	/* Hours 01-12 AM/PM || 00-23 */
97 #define RTC_HRS_ALARM		0x05	/* Alarm Hours 01-12 AM/PM || 00-23 */
98 #define RTC_WDAY		0x06	/* Day of Week 01-07 */
99 #define RTC_MDAY		0x07	/* Day of Month 01-31 */
100 #define RTC_MONTH		0x08	/* Month 01-12 */
101 #define RTC_YEAR		0x09	/* Year 00-99 */
102 #define RTC_CENTURY		0x48	/* Century 00-99 */
103 #define RTC_MDAY_ALARM		0x49	/* Alarm Day of Month 01-31 */
104 
105 
106 /*
107  * Bit masks for the Time registers in BCD Mode (DM = 0).
108  */
109 #define RTC_SECS_BCD_MASK	0x7f	/* - x x x x x x x */
110 #define RTC_MINS_BCD_MASK	0x7f	/* - x x x x x x x */
111 #define RTC_HRS_12_BCD_MASK	0x1f	/* - - - x x x x x */
112 #define RTC_HRS_24_BCD_MASK	0x3f	/* - - x x x x x x */
113 #define RTC_MDAY_BCD_MASK	0x3f	/* - - x x x x x x */
114 #define RTC_MONTH_BCD_MASK	0x1f	/* - - - x x x x x */
115 #define RTC_YEAR_BCD_MASK	0xff	/* x x x x x x x x */
116 
117 /*
118  * Bit masks for the Time registers in BIN Mode (DM = 1).
119  */
120 #define RTC_SECS_BIN_MASK	0x3f	/* - - x x x x x x */
121 #define RTC_MINS_BIN_MASK	0x3f	/* - - x x x x x x */
122 #define RTC_HRS_12_BIN_MASK	0x0f	/* - - - - x x x x */
123 #define RTC_HRS_24_BIN_MASK	0x1f	/* - - - x x x x x */
124 #define RTC_MDAY_BIN_MASK	0x1f	/* - - - x x x x x */
125 #define RTC_MONTH_BIN_MASK	0x0f	/* - - - - x x x x */
126 #define RTC_YEAR_BIN_MASK	0x7f	/* - x x x x x x x */
127 
128 /*
129  * Bit masks common for the Time registers in BCD or BIN Mode.
130  */
131 #define RTC_WDAY_MASK		0x07	/* - - - - - x x x */
132 #define RTC_CENTURY_MASK	0xff	/* x x x x x x x x */
133 #define RTC_MDAY_ALARM_MASK	0xff	/* x x x x x x x x */
134 #define RTC_HRS_AMPM_MASK	BIT(7)	/* Mask for the AM/PM bit */
135 
136 
137 
138 /*
139  * Control Registers.
140  */
141 #define RTC_CTRL_A		0x0a	/* Control Register A */
142 #define RTC_CTRL_B		0x0b	/* Control Register B */
143 #define RTC_CTRL_C		0x0c	/* Control Register C */
144 #define RTC_CTRL_D		0x0d	/* Control Register D */
145 #define RTC_EXT_CTRL_4A		0x4a	/* Extended Control Register 4A */
146 #define RTC_EXT_CTRL_4B		0x4b	/* Extended Control Register 4B */
147 
148 
149 /*
150  * Bit names in Control Register A.
151  */
152 #define RTC_CTRL_A_UIP		BIT(7)	/* Update In Progress */
153 #define RTC_CTRL_A_DV2		BIT(6)	/* Countdown Chain */
154 #define RTC_CTRL_A_DV1		BIT(5)	/* Oscillator Enable */
155 #define RTC_CTRL_A_DV0		BIT(4)	/* Bank Select */
156 #define RTC_CTRL_A_RS2		BIT(2)	/* Rate-Selection Bit 2 */
157 #define RTC_CTRL_A_RS3		BIT(3)	/* Rate-Selection Bit 3 */
158 #define RTC_CTRL_A_RS1		BIT(1)	/* Rate-Selection Bit 1 */
159 #define RTC_CTRL_A_RS0		BIT(0)	/* Rate-Selection Bit 0 */
160 #define RTC_CTRL_A_RS_MASK	0x0f	/* RS3 + RS2 + RS1 + RS0 */
161 
162 /*
163  * Bit names in Control Register B.
164  */
165 #define RTC_CTRL_B_SET		BIT(7)	/* SET Bit */
166 #define RTC_CTRL_B_PIE		BIT(6)	/* Periodic-Interrupt Enable */
167 #define RTC_CTRL_B_AIE		BIT(5)	/* Alarm-Interrupt Enable */
168 #define RTC_CTRL_B_UIE		BIT(4)	/* Update-Ended Interrupt-Enable */
169 #define RTC_CTRL_B_SQWE		BIT(3)	/* Square-Wave Enable */
170 #define RTC_CTRL_B_DM		BIT(2)	/* Data Mode */
171 #define RTC_CTRL_B_2412		BIT(1)	/* 12-Hr/24-Hr Mode */
172 #define RTC_CTRL_B_DSE		BIT(0)	/* Daylight Savings Enable */
173 #define RTC_CTRL_B_PAU_MASK	0x70	/* PIE + AIE + UIE */
174 
175 
176 /*
177  * Bit names in Control Register C.
178  *
179  * BIT(0), BIT(1), BIT(2), & BIT(3) are unused, always return 0, and cannot
180  * be written to.
181  */
182 #define RTC_CTRL_C_IRQF		BIT(7)	/* Interrupt-Request Flag */
183 #define RTC_CTRL_C_PF		BIT(6)	/* Periodic-Interrupt Flag */
184 #define RTC_CTRL_C_AF		BIT(5)	/* Alarm-Interrupt Flag */
185 #define RTC_CTRL_C_UF		BIT(4)	/* Update-Ended Interrupt Flag */
186 #define RTC_CTRL_C_PAU_MASK	0x70	/* PF + AF + UF */
187 
188 
189 /*
190  * Bit names in Control Register D.
191  *
192  * BIT(0) through BIT(6) are unused, always return 0, and cannot
193  * be written to.
194  */
195 #define RTC_CTRL_D_VRT		BIT(7)	/* Valid RAM and Time */
196 
197 
198 /*
199  * Bit names in Extended Control Register 4A.
200  *
201  * On the DS1685/DS1687/DS1689/DS1693, BIT(4) and BIT(5) are reserved for
202  * future use.  They can be read from and written to, but have no effect
203  * on the RTC's operation.
204  *
205  * On the DS17x85/DS17x87, BIT(5) is Burst-Mode Enable (BME), and allows
206  * access to the extended NV-SRAM by automatically incrementing the address
207  * register when they are read from or written to.
208  */
209 #define RTC_CTRL_4A_VRT2	BIT(7)	/* Auxillary Battery Status */
210 #define RTC_CTRL_4A_INCR	BIT(6)	/* Increment-in-Progress Status */
211 #define RTC_CTRL_4A_PAB		BIT(3)	/* Power-Active Bar Control */
212 #define RTC_CTRL_4A_RF		BIT(2)	/* RAM-Clear Flag */
213 #define RTC_CTRL_4A_WF		BIT(1)	/* Wake-Up Alarm Flag */
214 #define RTC_CTRL_4A_KF		BIT(0)	/* Kickstart Flag */
215 #if !defined(CONFIG_RTC_DRV_DS1685) && !defined(CONFIG_RTC_DRV_DS1689)
216 #define RTC_CTRL_4A_BME		BIT(5)	/* Burst-Mode Enable */
217 #endif
218 #define RTC_CTRL_4A_RWK_MASK	0x07	/* RF + WF + KF */
219 
220 
221 /*
222  * Bit names in Extended Control Register 4B.
223  */
224 #define RTC_CTRL_4B_ABE		BIT(7)	/* Auxillary Battery Enable */
225 #define RTC_CTRL_4B_E32K	BIT(6)	/* Enable 32.768Hz on SQW Pin */
226 #define RTC_CTRL_4B_CS		BIT(5)	/* Crystal Select */
227 #define RTC_CTRL_4B_RCE		BIT(4)	/* RAM Clear-Enable */
228 #define RTC_CTRL_4B_PRS		BIT(3)	/* PAB Reset-Select */
229 #define RTC_CTRL_4B_RIE		BIT(2)	/* RAM Clear-Interrupt Enable */
230 #define RTC_CTRL_4B_WIE		BIT(1)	/* Wake-Up Alarm-Interrupt Enable */
231 #define RTC_CTRL_4B_KSE		BIT(0)	/* Kickstart Interrupt-Enable */
232 #define RTC_CTRL_4B_RWK_MASK	0x07	/* RIE + WIE + KSE */
233 
234 
235 /*
236  * Misc register names in Bank 1.
237  *
238  * The DV0 bit in Control Register A must be set to 1 for these registers
239  * to become available, including Extended Control Registers 4A & 4B.
240  */
241 #define RTC_BANK1_SSN_MODEL	0x40	/* Model Number */
242 #define RTC_BANK1_SSN_BYTE_1	0x41	/* 1st Byte of Serial Number */
243 #define RTC_BANK1_SSN_BYTE_2	0x42	/* 2nd Byte of Serial Number */
244 #define RTC_BANK1_SSN_BYTE_3	0x43	/* 3rd Byte of Serial Number */
245 #define RTC_BANK1_SSN_BYTE_4	0x44	/* 4th Byte of Serial Number */
246 #define RTC_BANK1_SSN_BYTE_5	0x45	/* 5th Byte of Serial Number */
247 #define RTC_BANK1_SSN_BYTE_6	0x46	/* 6th Byte of Serial Number */
248 #define RTC_BANK1_SSN_CRC	0x47	/* Serial CRC Byte */
249 #define RTC_BANK1_RAM_DATA_PORT	0x53	/* Extended RAM Data Port */
250 
251 
252 /*
253  * Model-specific registers in Bank 1.
254  *
255  * The addresses below differ depending on the model of the RTC chip
256  * selected in the kernel configuration.  Not all of these features are
257  * supported in the main driver at present.
258  *
259  * DS1685/DS1687   - Extended NV-SRAM address (LSB only).
260  * DS1689/DS1693   - Vcc, Vbat, Pwr Cycle Counters & Customer-specific S/N.
261  * DS17x85/DS17x87 - Extended NV-SRAM addresses (MSB & LSB) & Write counter.
262  */
263 #if defined(CONFIG_RTC_DRV_DS1685)
264 #define RTC_BANK1_RAM_ADDR	0x50	/* NV-SRAM Addr */
265 #elif defined(CONFIG_RTC_DRV_DS1689)
266 #define RTC_BANK1_VCC_CTR_LSB	0x54	/* Vcc Counter Addr (LSB) */
267 #define RTC_BANK1_VCC_CTR_MSB	0x57	/* Vcc Counter Addr (MSB) */
268 #define RTC_BANK1_VBAT_CTR_LSB	0x58	/* Vbat Counter Addr (LSB) */
269 #define RTC_BANK1_VBAT_CTR_MSB	0x5b	/* Vbat Counter Addr (MSB) */
270 #define RTC_BANK1_PWR_CTR_LSB	0x5c	/* Pwr Cycle Counter Addr (LSB) */
271 #define RTC_BANK1_PWR_CTR_MSB	0x5d	/* Pwr Cycle Counter Addr (MSB) */
272 #define RTC_BANK1_UNIQ_SN	0x60	/* Customer-specific S/N */
273 #else /* DS17x85/DS17x87 */
274 #define RTC_BANK1_RAM_ADDR_LSB	0x50	/* NV-SRAM Addr (LSB) */
275 #define RTC_BANK1_RAM_ADDR_MSB	0x51	/* NV-SRAM Addr (MSB) */
276 #define RTC_BANK1_WRITE_CTR	0x5e	/* RTC Write Counter */
277 #endif
278 
279 
280 /*
281  * Model numbers.
282  *
283  * The DS1688/DS1691 and DS1689/DS1693 chips share the same model number
284  * and the manual doesn't indicate any major differences.  As such, they
285  * are regarded as the same chip in this driver.
286  */
287 #define RTC_MODEL_DS1685	0x71	/* DS1685/DS1687 */
288 #define RTC_MODEL_DS17285	0x72	/* DS17285/DS17287 */
289 #define RTC_MODEL_DS1689	0x73	/* DS1688/DS1691/DS1689/DS1693 */
290 #define RTC_MODEL_DS17485	0x74	/* DS17485/DS17487 */
291 #define RTC_MODEL_DS17885	0x78	/* DS17885/DS17887 */
292 
293 
294 /*
295  * Periodic Interrupt Rates / Square-Wave Output Frequency
296  *
297  * Periodic rates are selected by setting the RS3-RS0 bits in Control
298  * Register A and enabled via either the E32K bit in Extended Control
299  * Register 4B or the SQWE bit in Control Register B.
300  *
301  * E32K overrides the settings of RS3-RS0 and outputs a frequency of 32768Hz
302  * on the SQW pin of the RTC chip.  While there are 16 possible selections,
303  * the 1-of-16 decoder is only able to divide the base 32768Hz signal into 13
304  * smaller frequencies.  The values 0x01 and 0x02 are not used and are
305  * synonymous with 0x08 and 0x09, respectively.
306  *
307  * When E32K is set to a logic 1, periodic interrupts are disabled and reading
308  * /dev/rtc will return -EINVAL.  This also applies if the periodic interrupt
309  * frequency is set to 0Hz.
310  *
311  * Not currently used by the rtc-ds1685 driver because the RTC core removed
312  * support for hardware-generated periodic-interrupts in favour of
313  * hrtimer-generated interrupts.  But these defines are kept around for use
314  * in userland, as documentation to the hardware, and possible future use if
315  * hardware-generated periodic interrupts are ever added back.
316  */
317 					/* E32K RS3 RS2 RS1 RS0 */
318 #define RTC_SQW_8192HZ		0x03	/*  0    0   0   1   1  */
319 #define RTC_SQW_4096HZ		0x04	/*  0    0   1   0   0  */
320 #define RTC_SQW_2048HZ		0x05	/*  0    0   1   0   1  */
321 #define RTC_SQW_1024HZ		0x06	/*  0    0   1   1   0  */
322 #define RTC_SQW_512HZ		0x07	/*  0    0   1   1   1  */
323 #define RTC_SQW_256HZ		0x08	/*  0    1   0   0   0  */
324 #define RTC_SQW_128HZ		0x09	/*  0    1   0   0   1  */
325 #define RTC_SQW_64HZ		0x0a	/*  0    1   0   1   0  */
326 #define RTC_SQW_32HZ		0x0b	/*  0    1   0   1   1  */
327 #define RTC_SQW_16HZ		0x0c	/*  0    1   1   0   0  */
328 #define RTC_SQW_8HZ		0x0d	/*  0    1   1   0   1  */
329 #define RTC_SQW_4HZ		0x0e	/*  0    1   1   1   0  */
330 #define RTC_SQW_2HZ		0x0f	/*  0    1   1   1   1  */
331 #define RTC_SQW_0HZ		0x00	/*  0    0   0   0   0  */
332 #define RTC_SQW_32768HZ		32768	/*  1    -   -   -   -  */
333 #define RTC_MAX_USER_FREQ	8192
334 
335 
336 /*
337  * NVRAM data & addresses:
338  *   - 50 bytes of NVRAM are available just past the clock registers.
339  *   - 64 additional bytes are available in Bank0.
340  *
341  * Extended, battery-backed NV-SRAM:
342  *   - DS1685/DS1687    - 128 bytes.
343  *   - DS1689/DS1693    - 0 bytes.
344  *   - DS17285/DS17287  - 2048 bytes.
345  *   - DS17485/DS17487  - 4096 bytes.
346  *   - DS17885/DS17887  - 8192 bytes.
347  */
348 #define NVRAM_TIME_BASE		0x0e	/* NVRAM Addr in Time regs */
349 #define NVRAM_BANK0_BASE	0x40	/* NVRAM Addr in Bank0 regs */
350 #define NVRAM_SZ_TIME		50
351 #define NVRAM_SZ_BANK0		64
352 #if defined(CONFIG_RTC_DRV_DS1685)
353 #  define NVRAM_SZ_EXTND	128
354 #elif defined(CONFIG_RTC_DRV_DS1689)
355 #  define NVRAM_SZ_EXTND	0
356 #elif defined(CONFIG_RTC_DRV_DS17285)
357 #  define NVRAM_SZ_EXTND	2048
358 #elif defined(CONFIG_RTC_DRV_DS17485)
359 #  define NVRAM_SZ_EXTND	4096
360 #elif defined(CONFIG_RTC_DRV_DS17885)
361 #  define NVRAM_SZ_EXTND	8192
362 #endif
363 #define NVRAM_TOTAL_SZ_BANK0	(NVRAM_SZ_TIME + NVRAM_SZ_BANK0)
364 #define NVRAM_TOTAL_SZ		(NVRAM_TOTAL_SZ_BANK0 + NVRAM_SZ_EXTND)
365 
366 
367 /*
368  * Function Prototypes.
369  */
370 extern void __noreturn
371 ds1685_rtc_poweroff(struct platform_device *pdev);
372 
373 #endif /* _LINUX_RTC_DS1685_H_ */
374