15 #define DRIVER_NAME "rtc-pcf8523"
23 #define REG_CONTROL3_PM_VDD (1 << 6) /* switch-over disabled */
26 #define REG_CONTROL3_BLF (1 << 2) /* battery low bit, read-only */
51 	msgs[0].addr = client->addr;  in pcf8523_read()
56 	msgs[1].addr = client->addr;  in pcf8523_read()
61 	err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));  in pcf8523_read()
76 	msg.addr = client->addr;  in pcf8523_write()
81 	err = i2c_transfer(client->adapter, &msg, 1);  in pcf8523_write()
102 	u32 load;  in pcf8523_load_capacitance()  local
110 	load = 12500;  in pcf8523_load_capacitance()
111 	of_property_read_u32(client->dev.of_node, "quartz-load-femtofarads",  in pcf8523_load_capacitance()
112 			     &load);  in pcf8523_load_capacitance()
114 	switch (load) {  in pcf8523_load_capacitance()
116 		dev_warn(&client->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 12500",  in pcf8523_load_capacitance()
117 			 load);  in pcf8523_load_capacitance()
198 		return -EINVAL;  in pcf8523_rtc_read_time()
201 	msgs[0].addr = client->addr;  in pcf8523_rtc_read_time()
206 	msgs[1].addr = client->addr;  in pcf8523_rtc_read_time()
211 	err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));  in pcf8523_rtc_read_time()
216 		return -EINVAL;  in pcf8523_rtc_read_time()
218 	tm->tm_sec = bcd2bin(regs[0] & 0x7f);  in pcf8523_rtc_read_time()
219 	tm->tm_min = bcd2bin(regs[1] & 0x7f);  in pcf8523_rtc_read_time()
220 	tm->tm_hour = bcd2bin(regs[2] & 0x3f);  in pcf8523_rtc_read_time()
221 	tm->tm_mday = bcd2bin(regs[3] & 0x3f);  in pcf8523_rtc_read_time()
222 	tm->tm_wday = regs[4] & 0x7;  in pcf8523_rtc_read_time()
223 	tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1;  in pcf8523_rtc_read_time()
224 	tm->tm_year = bcd2bin(regs[6]) + 100;  in pcf8523_rtc_read_time()
239 	 * After 2100-02-28 we could start interpreting the year to be in the  in pcf8523_rtc_set_time()
241 	 * because the chip handles YEAR=0x00 (and the out-of-spec  in pcf8523_rtc_set_time()
244 	if (tm->tm_year < 100 || tm->tm_year >= 200)  in pcf8523_rtc_set_time()
245 		return -EINVAL;  in pcf8523_rtc_set_time()
253 	regs[1] = bin2bcd(tm->tm_sec);  in pcf8523_rtc_set_time()
254 	regs[2] = bin2bcd(tm->tm_min);  in pcf8523_rtc_set_time()
255 	regs[3] = bin2bcd(tm->tm_hour);  in pcf8523_rtc_set_time()
256 	regs[4] = bin2bcd(tm->tm_mday);  in pcf8523_rtc_set_time()
257 	regs[5] = tm->tm_wday;  in pcf8523_rtc_set_time()
258 	regs[6] = bin2bcd(tm->tm_mon + 1);  in pcf8523_rtc_set_time()
259 	regs[7] = bin2bcd(tm->tm_year - 100);  in pcf8523_rtc_set_time()
261 	msg.addr = client->addr;  in pcf8523_rtc_set_time()
266 	err = i2c_transfer(client->adapter, &msg, 1);  in pcf8523_rtc_set_time()
294 			return -EFAULT;  in pcf8523_rtc_ioctl()
298 		return -ENOIOCTLCMD;  in pcf8523_rtc_ioctl()
316 	/* sign extend the 7-bit offset value */  in pcf8523_rtc_read_offset()
329 	reg_m0 = clamp(DIV_ROUND_CLOSEST(offset, 4340), -64L, 63L);  in pcf8523_rtc_set_offset()
330 	reg_m1 = clamp(DIV_ROUND_CLOSEST(offset, 4069), -64L, 63L);  in pcf8523_rtc_set_offset()
332 	if (abs(reg_m0 * 4340 - offset) < abs(reg_m1 * 4069 - offset))  in pcf8523_rtc_set_offset()
354 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))  in pcf8523_probe()
355 		return -ENODEV;  in pcf8523_probe()
357 	pcf = devm_kzalloc(&client->dev, sizeof(*pcf), GFP_KERNEL);  in pcf8523_probe()
359 		return -ENOMEM;  in pcf8523_probe()
363 		dev_warn(&client->dev, "failed to set xtal load capacitance: %d",  in pcf8523_probe()
370 	pcf->rtc = devm_rtc_device_register(&client->dev, DRIVER_NAME,  in pcf8523_probe()
372 	if (IS_ERR(pcf->rtc))  in pcf8523_probe()
373 		return PTR_ERR(pcf->rtc);  in pcf8523_probe()
404 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");