Merge tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "It is now possible to add custom sysfs attributes while avoiding a
  possible race condition. Unused code has been removed resulting in a
  nice reduction of the code base. And more drivers have been switched
  to SPDX by their maintainers.

 Summary:

  Subsystem:
   - new helpers to add custom sysfs attributes
   - struct rtc_task removal along with rtc_irq_[un]register()
   - rtc_irq_set_state and rtc_irq_set_freq are not exported anymore

  Drivers:
   - armada38x: reset after rtc power loss
   - ds1307: now supports m41t11
   - isl1208: now supports isl1219 and tamper detection
   - pcf2127: internal SRAM support"

* tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (34 commits)
  rtc: ds1307: simplify hwmon config
  rtc: s5m: Add SPDX license identifier
  rtc: maxim: Add SPDX license identifiers
  rtc: isl1219: add device tree documentation
  rtc: isl1208: set ev-evienb bit from device tree
  rtc: isl1208: Add "evdet" interrupt source for isl1219
  rtc: isl1208: add support for isl1219 with tamper detection
  rtc: sysfs: facilitate attribute add to rtc device
  rtc: remove struct rtc_task
  char: rtc: remove task handling
  rtc: pcf85063: preserve control register value between stop and start
  rtc: sh: remove unused variable rtc_dev
  rtc: unexport rtc_irq_set_*
  rtc: simplify rtc_irq_set_state/rtc_irq_set_freq
  rtc: remove irq_task and irq_task_lock
  rtc: remove rtc_irq_register/rtc_irq_unregister
  rtc: sh: remove dead code
  rtc: sa1100: don't set PIE frequency
  rtc: ds1307: support m41t11 variant
  rtc: ds1307: fix data pointer to m41t0
  ...

28 files changed, 524 insertions, 971 deletions

diff --git a/Documentation/devicetree/bindings/rtc/isil,isl1219.txt b/Documentation/devicetree/bindings/rtc/isil,isl1219.txt
new file mode 100644
index 000000000000..c3efd48e91c2
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/isil,isl1219.txt
@@ -0,0 +1,29 @@
+Intersil ISL1219 I2C RTC/Alarm chip with event in
+
+ISL1219 has additional pins EVIN and #EVDET for tamper detection.
+
+Required properties supported by the device:
+
+ - "compatible": must be "isil,isl1219"
+ - "reg": I2C bus address of the device
+
+Optional properties:
+
+ - "interrupt-names": list which may contains "irq" and "evdet"
+ - "interrupts": list of interrupts for "irq" and "evdet"
+ - "isil,ev-evienb": if present EV.EVIENB bit is set to the specified
+                     value for proper operation.
+
+
+Example isl1219 node with #IRQ pin connected to SoC gpio1 pin12
+ and #EVDET pin connected to SoC gpio2 pin 24:
+
+	isl1219: rtc@68 {
+		compatible = "isil,isl1219";
+		reg = <0x68>;
+		interrupt-names = "irq", "evdet";
+		interrupts-extended = <&gpio1 12 IRQ_TYPE_EDGE_FALLING>,
+			<&gpio2 24 IRQ_TYPE_EDGE_FALLING>;
+		isil,ev-evienb = <1>;
+	};
+
diff --git a/Documentation/devicetree/bindings/rtc/rtc-ds1307.txt b/Documentation/devicetree/bindings/rtc/rtc-ds1307.txt
index 226cc93df875..eebfbe04207a 100644
--- a/Documentation/devicetree/bindings/rtc/rtc-ds1307.txt
+++ b/Documentation/devicetree/bindings/rtc/rtc-ds1307.txt
@@ -13,6 +13,7 @@ Required properties:
 	"maxim,ds3231",
 	"st,m41t0",
 	"st,m41t00",
+	"st,m41t11",
 	"microchip,mcp7940x",
 	"microchip,mcp7941x",
 	"pericom,pt7c4338",
diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c
index 94fedeeec035..4948c8bda6b1 100644
--- a/drivers/char/rtc.c
+++ b/drivers/char/rtc.c
@@ -193,14 +193,6 @@ static unsigned long rtc_freq;		/* Current periodic IRQ rate	*/
 static unsigned long rtc_irq_data;	/* our output to the world	*/
 static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */
 
-#ifdef RTC_IRQ
-/*
- * rtc_task_lock nests inside rtc_lock.
- */
-static DEFINE_SPINLOCK(rtc_task_lock);
-static rtc_task_t *rtc_callback;
-#endif
-
 /*
  *	If this driver ever becomes modularised, it will be really nice
  *	to make the epoch retain its value across module reload...
@@ -264,11 +256,6 @@ static irqreturn_t rtc_interrupt(int irq, void *dev_id)
 
 	spin_unlock(&rtc_lock);
 
-	/* Now do the rest of the actions */
-	spin_lock(&rtc_task_lock);
-	if (rtc_callback)
-		rtc_callback->func(rtc_callback->private_data);
-	spin_unlock(&rtc_task_lock);
 	wake_up_interruptible(&rtc_wait);
 
 	kill_fasync(&rtc_async_queue, SIGIO, POLL_IN);
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index a2ba5db36145..7d7be60a2413 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -244,15 +244,6 @@ config RTC_DRV_DS1307
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-ds1307.
 
-config RTC_DRV_DS1307_HWMON
-	bool "HWMON support for rtc-ds1307"
-	depends on RTC_DRV_DS1307 && HWMON
-	depends on !(RTC_DRV_DS1307=y && HWMON=m)
-	default y
-	help
-	  Say Y here if you want to expose temperature sensor data on
-	  rtc-ds1307 (only DS3231)
-
 config RTC_DRV_DS1307_CENTURY
 	bool "Century bit support for rtc-ds1307"
 	depends on RTC_DRV_DS1307
@@ -1027,18 +1018,6 @@ config RTC_DS1685_PROC_REGS
 
 	  Unless you are debugging this driver, choose N.
 
-config RTC_DS1685_SYSFS_REGS
-	bool "SysFS access to RTC register bits"
-	depends on RTC_DRV_DS1685_FAMILY && SYSFS
-	help
-	  Enable this to provide access to the RTC control register bits
-	  in /sys.  Some of the bits are read-write, others are read-only.
-
-	  Keep in mind that reading Control C's bits automatically clears
-	  all pending IRQ flags - this can cause lost interrupts.
-
-	  If you know that you need access to these bits, choose Y, Else N.
-
 config RTC_DRV_DS1742
 	tristate "Maxim/Dallas DS1742/1743"
 	depends on HAS_IOMEM
diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index d37588f08055..0fca4d74c76b 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -68,7 +68,7 @@ static int rtc_suspend(struct device *dev)
 		return 0;
 	}
 
-	getnstimeofday64(&old_system);
+	ktime_get_real_ts64(&old_system);
 	old_rtc.tv_sec = rtc_tm_to_time64(&tm);
 
 
@@ -110,7 +110,7 @@ static int rtc_resume(struct device *dev)
 		return 0;
 
 	/* snapshot the current rtc and system time at resume */
-	getnstimeofday64(&new_system);
+	ktime_get_real_ts64(&new_system);
 	err = rtc_read_time(rtc, &tm);
 	if (err < 0) {
 		pr_debug("%s:  fail to read rtc time\n", dev_name(&rtc->dev));
@@ -172,7 +172,6 @@ static struct rtc_device *rtc_allocate_device(void)
 
 	mutex_init(&rtc->ops_lock);
 	spin_lock_init(&rtc->irq_lock);
-	spin_lock_init(&rtc->irq_task_lock);
 	init_waitqueue_head(&rtc->irq_queue);
 
 	/* Init timerqueue */
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index bac1eeb3d312..3d577e259e91 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -607,12 +607,6 @@ void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
 	rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode);
 	spin_unlock_irqrestore(&rtc->irq_lock, flags);
 
-	/* call the task func */
-	spin_lock_irqsave(&rtc->irq_task_lock, flags);
-	if (rtc->irq_task)
-		rtc->irq_task->func(rtc->irq_task->private_data);
-	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
-
 	wake_up_interruptible(&rtc->irq_queue);
 	kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
 }
@@ -721,39 +715,6 @@ void rtc_class_close(struct rtc_device *rtc)
 }
 EXPORT_SYMBOL_GPL(rtc_class_close);
 
-int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task)
-{
-	int retval = -EBUSY;
-
-	if (task == NULL || task->func == NULL)
-		return -EINVAL;
-
-	/* Cannot register while the char dev is in use */
-	if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags))
-		return -EBUSY;
-
-	spin_lock_irq(&rtc->irq_task_lock);
-	if (rtc->irq_task == NULL) {
-		rtc->irq_task = task;
-		retval = 0;
-	}
-	spin_unlock_irq(&rtc->irq_task_lock);
-
-	clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
-
-	return retval;
-}
-EXPORT_SYMBOL_GPL(rtc_irq_register);
-
-void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task)
-{
-	spin_lock_irq(&rtc->irq_task_lock);
-	if (rtc->irq_task == task)
-		rtc->irq_task = NULL;
-	spin_unlock_irq(&rtc->irq_task_lock);
-}
-EXPORT_SYMBOL_GPL(rtc_irq_unregister);
-
 static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled)
 {
 	/*
@@ -785,71 +746,45 @@ static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled)
  * Context: any
  *
  * Note that rtc_irq_set_freq() should previously have been used to
- * specify the desired frequency of periodic IRQ task->func() callbacks.
+ * specify the desired frequency of periodic IRQ.
  */
-int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled)
+int rtc_irq_set_state(struct rtc_device *rtc, int enabled)
 {
 	int err = 0;
-	unsigned long flags;
 
-retry:
-	spin_lock_irqsave(&rtc->irq_task_lock, flags);
-	if (rtc->irq_task != NULL && task == NULL)
-		err = -EBUSY;
-	else if (rtc->irq_task != task)
-		err = -EACCES;
-	else {
-		if (rtc_update_hrtimer(rtc, enabled) < 0) {
-			spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
-			cpu_relax();
-			goto retry;
-		}
-		rtc->pie_enabled = enabled;
-	}
-	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
+	while (rtc_update_hrtimer(rtc, enabled) < 0)
+		cpu_relax();
+
+	rtc->pie_enabled = enabled;
 
 	trace_rtc_irq_set_state(enabled, err);
 	return err;
 }
-EXPORT_SYMBOL_GPL(rtc_irq_set_state);
 
 /**
  * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ
  * @rtc: the rtc device
  * @task: currently registered with rtc_irq_register()
- * @freq: positive frequency with which task->func() will be called
+ * @freq: positive frequency
  * Context: any
  *
  * Note that rtc_irq_set_state() is used to enable or disable the
  * periodic IRQs.
  */
-int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
+int rtc_irq_set_freq(struct rtc_device *rtc, int freq)
 {
 	int err = 0;
-	unsigned long flags;
 
 	if (freq <= 0 || freq > RTC_MAX_FREQ)
 		return -EINVAL;
-retry:
-	spin_lock_irqsave(&rtc->irq_task_lock, flags);
-	if (rtc->irq_task != NULL && task == NULL)
-		err = -EBUSY;
-	else if (rtc->irq_task != task)
-		err = -EACCES;
-	else {
-		rtc->irq_freq = freq;
-		if (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0) {
-			spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
-			cpu_relax();
-			goto retry;
-		}
-	}
-	spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
+
+	rtc->irq_freq = freq;
+	while (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0)
+		cpu_relax();
 
 	trace_rtc_irq_set_freq(freq, err);
 	return err;
 }
-EXPORT_SYMBOL_GPL(rtc_irq_set_freq);
 
 /**
  * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue
@@ -979,8 +914,8 @@ again:
 		timerqueue_del(&rtc->timerqueue, &timer->node);
 		trace_rtc_timer_dequeue(timer);
 		timer->enabled = 0;
-		if (timer->task.func)
-			timer->task.func(timer->task.private_data);
+		if (timer->func)
+			timer->func(timer->private_data);
 
 		trace_rtc_timer_fired(timer);
 		/* Re-add/fwd periodic timers */
@@ -1035,8 +970,8 @@ void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data)
 {
 	timerqueue_init(&timer->node);
 	timer->enabled = 0;
-	timer->task.func = f;
-	timer->task.private_data = data;
+	timer->func = f;
+	timer->private_data = data;
 }
 
 /* rtc_timer_start - Sets an rtc_timer to fire in the future
diff --git a/drivers/rtc/rtc-armada38x.c b/drivers/rtc/rtc-armada38x.c
index 1e4978c96ffd..bde53c8ccee2 100644
--- a/drivers/rtc/rtc-armada38x.c
+++ b/drivers/rtc/rtc-armada38x.c
@@ -30,6 +30,8 @@
 #define RTC_IRQ_FREQ_1HZ	    BIT(2)
 #define RTC_CCR		    0x18
 #define RTC_CCR_MODE		    BIT(15)
+#define RTC_CONF_TEST	    0x1C
+#define RTC_NOMINAL_TIMING	    BIT(13)
 
 #define RTC_TIME	    0xC
 #define RTC_ALARM1	    0x10
@@ -75,6 +77,7 @@ struct armada38x_rtc {
 	void __iomem	    *regs_soc;
 	spinlock_t	    lock;
 	int		    irq;
+	bool		    initialized;
 	struct value_to_freq *val_to_freq;
 	struct armada38x_rtc_data *data;
 };
@@ -226,6 +229,23 @@ static int armada38x_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	return 0;
 }
 
+static void armada38x_rtc_reset(struct armada38x_rtc *rtc)
+{
+	u32 reg;
+
+	reg = rtc->data->read_rtc_reg(rtc, RTC_CONF_TEST);
+	/* If bits [7:0] are non-zero, assume RTC was uninitialized */
+	if (reg & 0xff) {
+		rtc_delayed_write(0, rtc, RTC_CONF_TEST);
+		msleep(500); /* Oscillator startup time */
+		rtc_delayed_write(0, rtc, RTC_TIME);
+		rtc_delayed_write(SOC_RTC_ALARM1 | SOC_RTC_ALARM2, rtc,
+				  RTC_STATUS);
+		rtc_delayed_write(RTC_NOMINAL_TIMING, rtc, RTC_CCR);
+	}
+	rtc->initialized = true;
+}
+
 static int armada38x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	struct armada38x_rtc *rtc = dev_get_drvdata(dev);
@@ -237,6 +257,9 @@ static int armada38x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	if (ret)
 		goto out;
 
+	if (!rtc->initialized)
+		armada38x_rtc_reset(rtc);
+
 	spin_lock_irqsave(&rtc->lock, flags);
 	rtc_delayed_write(time, rtc, RTC_TIME);
 	spin_unlock_irqrestore(&rtc->lock, flags);
diff --git a/drivers/rtc/rtc-bq4802.c b/drivers/rtc/rtc-bq4802.c
index d768f6747961..113493b52149 100644
--- a/drivers/rtc/rtc-bq4802.c
+++ b/drivers/rtc/rtc-bq4802.c
@@ -162,6 +162,10 @@ static int bq4802_probe(struct platform_device *pdev)
 	} else if (p->r->flags & IORESOURCE_MEM) {
 		p->regs = devm_ioremap(&pdev->dev, p->r->start,
 					resource_size(p->r));
+		if (!p->regs){
+			err = -ENOMEM;
+			goto out;
+		}
 		p->read = bq4802_read_mem;
 		p->write = bq4802_write_mem;
 	} else {
diff --git a/drivers/rtc/rtc-core.h b/drivers/rtc/rtc-core.h
index 0abf98983e13..ccc17a2e293d 100644
--- a/drivers/rtc/rtc-core.h
+++ b/drivers/rtc/rtc-core.h
@@ -40,9 +40,23 @@ static inline void rtc_proc_del_device(struct rtc_device *rtc)
 
 #ifdef CONFIG_RTC_INTF_SYSFS
 const struct attribute_group **rtc_get_dev_attribute_groups(void);
+int rtc_add_group(struct rtc_device *rtc, const struct attribute_group *grp);
+int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps);
 #else
 static inline const struct attribute_group **rtc_get_dev_attribute_groups(void)
 {
 	return NULL;
 }
+
+static inline
+int rtc_add_group(struct rtc_device *rtc, const struct attribute_group *grp)
+{
+	return 0;
+}
+
+static inline
+int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps)
+{
+	return 0;
+}
 #endif
diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c
index efa221e8bc22..43d962a9c210 100644
--- a/drivers/rtc/rtc-dev.c
+++ b/drivers/rtc/rtc-dev.c
@@ -341,11 +341,11 @@ static long rtc_dev_ioctl(struct file *file,
 		return rtc_set_time(rtc, &tm);
 
 	case RTC_PIE_ON:
-		err = rtc_irq_set_state(rtc, NULL, 1);
+		err = rtc_irq_set_state(rtc, 1);
 		break;
 
 	case RTC_PIE_OFF:
-		err = rtc_irq_set_state(rtc, NULL, 0);
+		err = rtc_irq_set_state(rtc, 0);
 		break;
 
 	case RTC_AIE_ON:
@@ -365,7 +365,7 @@ static long rtc_dev_ioctl(struct file *file,
 		return rtc_update_irq_enable(rtc, 0);
 
 	case RTC_IRQP_SET:
-		err = rtc_irq_set_freq(rtc, NULL, arg);
+		err = rtc_irq_set_freq(rtc, arg);
 		break;
 
 	case RTC_IRQP_READ:
@@ -427,7 +427,7 @@ static int rtc_dev_release(struct inode *inode, struct file *file)
 	/* Keep ioctl until all drivers are converted */
 	rtc_dev_ioctl(file, RTC_UIE_OFF, 0);
 	rtc_update_irq_enable(rtc, 0);
-	rtc_irq_set_state(rtc, NULL, 0);
+	rtc_irq_set_state(rtc, 0);
 
 	clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
 	return 0;
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index e9ec4160d7f6..4b2b4627daeb 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -44,6 +44,7 @@ enum ds_type {
 	ds_3231,
 	m41t0,
 	m41t00,
+	m41t11,
 	mcp794xx,
 	rx_8025,
 	rx_8130,
@@ -227,6 +228,11 @@ static const struct chip_desc chips[last_ds_type] = {
 		.irq_handler = rx8130_irq,
 		.rtc_ops = &rx8130_rtc_ops,
 	},
+	[m41t11] = {
+		/* this is battery backed SRAM */
+		.nvram_offset	= 8,
+		.nvram_size	= 56,
+	},
 	[mcp794xx] = {
 		.alarm		= 1,
 		/* this is battery backed SRAM */
@@ -249,6 +255,7 @@ static const struct i2c_device_id ds1307_id[] = {
 	{ "ds3231", ds_3231 },
 	{ "m41t0", m41t0 },
 	{ "m41t00", m41t00 },
+	{ "m41t11", m41t11 },
 	{ "mcp7940x", mcp794xx },
 	{ "mcp7941x", mcp794xx },
 	{ "pt7c4338", ds_1307 },
@@ -299,13 +306,17 @@ static const struct of_device_id ds1307_of_match[] = {
 	},
 	{
 		.compatible = "st,m41t0",
-		.data = (void *)m41t00
+		.data = (void *)m41t0
 	},
 	{
 		.compatible = "st,m41t00",
 		.data = (void *)m41t00
 	},
 	{
+		.compatible = "st,m41t11",
+		.data = (void *)m41t11
+	},
+	{
 		.compatible = "microchip,mcp7940x",
 		.data = (void *)mcp794xx
 	},
@@ -347,6 +358,7 @@ static const struct acpi_device_id ds1307_acpi_ids[] = {
 	{ .id = "DS3231", .driver_data = ds_3231 },
 	{ .id = "M41T0", .driver_data = m41t0 },
 	{ .id = "M41T00", .driver_data = m41t00 },
+	{ .id = "M41T11", .driver_data = m41t11 },
 	{ .id = "MCP7940X", .driver_data = mcp794xx },
 	{ .id = "MCP7941X", .driver_data = mcp794xx },
 	{ .id = "PT7C4338", .driver_data = ds_1307 },
@@ -1030,7 +1042,7 @@ static u8 ds1307_trickle_init(struct ds1307 *ds1307,
 
 /*----------------------------------------------------------------------*/
 
-#ifdef CONFIG_RTC_DRV_DS1307_HWMON
+#if IS_REACHABLE(CONFIG_HWMON)
 
 /*
  * Temperature sensor support for ds3231 devices.
@@ -1576,6 +1588,7 @@ read_rtc:
 	case ds_1307:
 	case m41t0:
 	case m41t00:
+	case m41t11:
 		/* clock halted?  turn it on, so clock can tick. */
 		if (tmp & DS1307_BIT_CH) {
 			regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
@@ -1641,6 +1654,7 @@ read_rtc:
 	case ds_1340:
 	case m41t0:
 	case m41t00:
+	case m41t11:
 		/*
 		 * NOTE: ignores century bits; fix before deploying
 		 * systems that will run through year 2100.
diff --git a/drivers/rtc/rtc-ds1685.c b/drivers/rtc/rtc-ds1685.c
index 5c0db6c8134c..6f39f683a98c 100644
--- a/drivers/rtc/rtc-ds1685.c
+++ b/drivers/rtc/rtc-ds1685.c
@@ -1188,552 +1188,6 @@ ds1685_rtc_sysfs_misc_grp = {
 	.attrs = ds1685_rtc_sysfs_misc_attrs,
 };
 
-#ifdef CONFIG_RTC_DS1685_SYSFS_REGS
-/**
- * struct ds1685_rtc_ctrl_regs.
- * @name: char pointer for the bit name.
- * @reg: control register the bit is in.
- * @bit: the bit's offset in the register.
- */
-struct ds1685_rtc_ctrl_regs {
-	const char *name;
-	const u8 reg;
-	const u8 bit;
-};
-
-/*
- * Ctrl register bit lookup table.
- */
-static const struct ds1685_rtc_ctrl_regs
-ds1685_ctrl_regs_table[] = {
-	{ "uip",  RTC_CTRL_A,      RTC_CTRL_A_UIP   },
-	{ "dv2",  RTC_CTRL_A,      RTC_CTRL_A_DV2   },
-	{ "dv1",  RTC_CTRL_A,      RTC_CTRL_A_DV1   },
-	{ "dv0",  RTC_CTRL_A,      RTC_CTRL_A_DV0   },
-	{ "rs3",  RTC_CTRL_A,      RTC_CTRL_A_RS3   },
-	{ "rs2",  RTC_CTRL_A,      RTC_CTRL_A_RS2   },
-	{ "rs1",  RTC_CTRL_A,      RTC_CTRL_A_RS1   },
-	{ "rs0",  RTC_CTRL_A,      RTC_CTRL_A_RS0   },
-	{ "set",  RTC_CTRL_B,      RTC_CTRL_B_SET   },
-	{ "pie",  RTC_CTRL_B,      RTC_CTRL_B_PIE   },
-	{ "aie",  RTC_CTRL_B,      RTC_CTRL_B_AIE   },
-	{ "uie",  RTC_CTRL_B,      RTC_CTRL_B_UIE   },
-	{ "sqwe", RTC_CTRL_B,      RTC_CTRL_B_SQWE  },
-	{ "dm",   RTC_CTRL_B,      RTC_CTRL_B_DM    },
-	{ "2412", RTC_CTRL_B,      RTC_CTRL_B_2412  },
-	{ "dse",  RTC_CTRL_B,      RTC_CTRL_B_DSE   },
-	{ "irqf", RTC_CTRL_C,      RTC_CTRL_C_IRQF  },
-	{ "pf",   RTC_CTRL_C,      RTC_CTRL_C_PF    },
-	{ "af",   RTC_CTRL_C,      RTC_CTRL_C_AF    },
-	{ "uf",   RTC_CTRL_C,      RTC_CTRL_C_UF    },
-	{ "vrt",  RTC_CTRL_D,      RTC_CTRL_D_VRT   },
-	{ "vrt2", RTC_EXT_CTRL_4A, RTC_CTRL_4A_VRT2 },
-	{ "incr", RTC_EXT_CTRL_4A, RTC_CTRL_4A_INCR },
-	{ "pab",  RTC_EXT_CTRL_4A, RTC_CTRL_4A_PAB  },
-	{ "rf",   RTC_EXT_CTRL_4A, RTC_CTRL_4A_RF   },
-	{ "wf",   RTC_EXT_CTRL_4A, RTC_CTRL_4A_WF   },
-	{ "kf",   RTC_EXT_CTRL_4A, RTC_CTRL_4A_KF   },
-#if !defined(CONFIG_RTC_DRV_DS1685) && !defined(CONFIG_RTC_DRV_DS1689)
-	{ "bme",  RTC_EXT_CTRL_4A, RTC_CTRL_4A_BME  },
-#endif
-	{ "abe",  RTC_EXT_CTRL_4B, RTC_CTRL_4B_ABE  },
-	{ "e32k", RTC_EXT_CTRL_4B, RTC_CTRL_4B_E32K },
-	{ "cs",   RTC_EXT_CTRL_4B, RTC_CTRL_4B_CS   },
-	{ "rce",  RTC_EXT_CTRL_4B, RTC_CTRL_4B_RCE  },
-	{ "prs",  RTC_EXT_CTRL_4B, RTC_CTRL_4B_PRS  },
-	{ "rie",  RTC_EXT_CTRL_4B, RTC_CTRL_4B_RIE  },
-	{ "wie",  RTC_EXT_CTRL_4B, RTC_CTRL_4B_WIE  },
-	{ "kse",  RTC_EXT_CTRL_4B, RTC_CTRL_4B_KSE  },
-	{ NULL,   0,               0                },
-};
-
-/**
- * ds1685_rtc_sysfs_ctrl_regs_lookup - ctrl register bit lookup function.
- * @name: ctrl register bit to look up in ds1685_ctrl_regs_table.
- */
-static const struct ds1685_rtc_ctrl_regs*
-ds1685_rtc_sysfs_ctrl_regs_lookup(const char *name)
-{
-	const struct ds1685_rtc_ctrl_regs *p = ds1685_ctrl_regs_table;
-
-	for (; p->name != NULL; ++p)
-		if (strcmp(p->name, name) == 0)
-			return p;
-
-	return NULL;
-}
-
-/**
- * ds1685_rtc_sysfs_ctrl_regs_show - reads a ctrl register bit via sysfs.
- * @dev: pointer to device structure.
- * @attr: pointer to device_attribute structure.
- * @buf: pointer to char array to hold the output.
- */
-static ssize_t
-ds1685_rtc_sysfs_ctrl_regs_show(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	u8 tmp;
-	struct ds1685_priv *rtc = dev_get_drvdata(dev);
-	const struct ds1685_rtc_ctrl_regs *reg_info =
-		ds1685_rtc_sysfs_ctrl_regs_lookup(attr->attr.name);
-
-	/* Make sure we actually matched something. */
-	if (!reg_info)
-		return -EINVAL;
-
-	/* No spinlock during a read -- mutex is already held. */
-	ds1685_rtc_switch_to_bank1(rtc);
-	tmp = rtc->read(rtc, reg_info->reg) & reg_info->bit;
-	ds1685_rtc_switch_to_bank0(rtc);
-
-	return sprintf(buf, "%d\n", (tmp ? 1 : 0));
-}
-
-/**
- * ds1685_rtc_sysfs_ctrl_regs_store - writes a ctrl register bit via sysfs.
- * @dev: pointer to device structure.
- * @attr: pointer to device_attribute structure.
- * @buf: pointer to char array to hold the output.
- * @count: number of bytes written.
- */
-static ssize_t
-ds1685_rtc_sysfs_ctrl_regs_store(struct device *dev,
-				 struct device_attribute *attr,
-				 const char *buf, size_t count)
-{
-	struct ds1685_priv *rtc = dev_get_drvdata(dev);
-	u8 reg = 0, bit = 0, tmp;
-	unsigned long flags;
-	long int val = 0;
-	const struct ds1685_rtc_ctrl_regs *reg_info =
-		ds1685_rtc_sysfs_ctrl_regs_lookup(attr->attr.name);
-
-	/* We only accept numbers. */
-	if (kstrtol(buf, 10, &val) < 0)
-		return -EINVAL;
-
-	/* bits are binary, 0 or 1 only. */
-	if ((val != 0) && (val != 1))
-		return -ERANGE;
-
-	/* Make sure we actually matched something. */
-	if (!reg_info)
-		return -EINVAL;
-
-	reg = reg_info->reg;
-	bit = reg_info->bit;
-
-	/* Safe to spinlock during a write. */
-	ds1685_rtc_begin_ctrl_access(rtc, &flags);
-	tmp = rtc->read(rtc, reg);
-	rtc->write(rtc, reg, (val ? (tmp | bit) : (tmp & ~(bit))));
-	ds1685_rtc_end_ctrl_access(rtc, flags);
-
-	return count;
-}
-
-/**
- * DS1685_RTC_SYSFS_CTRL_REG_RO - device_attribute for read-only register bit.
- * @bit: bit to read.
- */
-#define DS1685_RTC_SYSFS_CTRL_REG_RO(bit)				\
-	static DEVICE_ATTR(bit, S_IRUGO,				\
-	ds1685_rtc_sysfs_ctrl_regs_show, NULL)
-
-/**
- * DS1685_RTC_SYSFS_CTRL_REG_RW - device_attribute for read-write register bit.
- * @bit: bit to read or write.
- */
-#define DS1685_RTC_SYSFS_CTRL_REG_RW(bit)				\
-	static DEVICE_ATTR(bit, S_IRUGO | S_IWUSR,			\
-	ds1685_rtc_sysfs_ctrl_regs_show,				\
-	ds1685_rtc_sysfs_ctrl_regs_store)
-
-/*
- * Control Register A bits.
- */
-DS1685_RTC_SYSFS_CTRL_REG_RO(uip);
-DS1685_RTC_SYSFS_CTRL_REG_RW(dv2);
-DS1685_RTC_SYSFS_CTRL_REG_RW(dv1);
-DS1685_RTC_SYSFS_CTRL_REG_RO(dv0);
-DS1685_RTC_SYSFS_CTRL_REG_RW(rs3);
-DS1685_RTC_SYSFS_CTRL_REG_RW(rs2);
-DS1685_RTC_SYSFS_CTRL_REG_RW(rs1);
-DS1685_RTC_SYSFS_CTRL_REG_RW(rs0);
-
-static struct attribute*
-ds1685_rtc_sysfs_ctrla_attrs[] = {
-	&dev_attr_uip.attr,
-	&dev_attr_dv2.attr,
-	&dev_attr_dv1.attr,
-	&dev_attr_dv0.attr,
-	&dev_attr_rs3.attr,
-	&dev_attr_rs2.attr,
-	&dev_attr_rs1.attr,
-	&dev_attr_rs0.attr,
-	NULL,
-};
-
-static const struct attribute_group
-ds1685_rtc_sysfs_ctrla_grp = {
-	.name = "ctrla",
-	.attrs = ds1685_rtc_sysfs_ctrla_attrs,
-};
-
-
-/*
- * Control Register B bits.
- */
-DS1685_RTC_SYSFS_CTRL_REG_RO(set);
-DS1685_RTC_SYSFS_CTRL_REG_RW(pie);
-DS1685_RTC_SYSFS_CTRL_REG_RW(aie);
-DS1685_RTC_SYSFS_CTRL_REG_RW(uie);
-DS1685_RTC_SYSFS_CTRL_REG_RW(sqwe);
-DS1685_RTC_SYSFS_CTRL_REG_RO(dm);
-DS1685_RTC_SYSFS_CTRL_REG_RO(2412);
-DS1685_RTC_SYSFS_CTRL_REG_RO(dse);
-
-static struct attribute*
-ds1685_rtc_sysfs_ctrlb_attrs[] = {
-	&dev_attr_set.attr,
-	&dev_attr_pie.attr,
-	&dev_attr_aie.attr,
-	&dev_attr_uie.attr,
-	&dev_attr_sqwe.attr,
-	&dev_attr_dm.attr,
-	&dev_attr_2412.attr,
-	&dev_attr_dse.attr,
-	NULL,
-};
-
-static const struct attribute_group
-ds1685_rtc_sysfs_ctrlb_grp = {
-	.name = "ctrlb",
-	.attrs = ds1685_rtc_sysfs_ctrlb_attrs,
-};
-
-/*
- * Control Register C bits.
- *
- * Reading Control C clears these bits!  Reading them individually can
- * possibly cause an interrupt to be missed.  Use the /proc interface
- * to see all the bits in this register simultaneously.
- */
-DS1685_RTC_SYSFS_CTRL_REG_RO(irqf);
-DS1685_RTC_SYSFS_CTRL_REG_RO(pf);
-DS1685_RTC_SYSFS_CTRL_REG_RO(af);
-DS1685_RTC_SYSFS_CTRL_REG_RO(uf);
-
-static struct attribute*
-ds1685_rtc_sysfs_ctrlc_attrs[] = {
-	&dev_attr_irqf.attr,
-	&dev_attr_pf.attr,
-	&dev_attr_af.attr,
-	&dev_attr_uf.attr,
-	NULL,
-};
-
-static const struct attribute_group
-ds1685_rtc_sysfs_ctrlc_grp = {
-	.name = "ctrlc",
-	.attrs = ds1685_rtc_sysfs_ctrlc_attrs,
-};
-
-/*
- * Control Register D bits.
- */
-DS1685_RTC_SYSFS_CTRL_REG_RO(vrt);
-
-static struct attribute*
-ds1685_rtc_sysfs_ctrld_attrs[] = {
-	&dev_attr_vrt.attr,
-	NULL,
-};
-
-static const struct attribute_group
-ds1685_rtc_sysfs_ctrld_grp = {
-	.name = "ctrld",
-	.attrs = ds1685_rtc_sysfs_ctrld_attrs,
-};
-
-/*
- * Control Register 4A bits.
- */
-DS1685_RTC_SYSFS_CTRL_REG_RO(vrt2);
-DS1685_RTC_SYSFS_CTRL_REG_RO(incr);
-DS1685_RTC_SYSFS_CTRL_REG_RW(pab);
-DS1685_RTC_SYSFS_CTRL_REG_RW(rf);
-DS1685_RTC_SYSFS_CTRL_REG_RW(wf);
-DS1685_RTC_SYSFS_CTRL_REG_RW(kf)