Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 776 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-max31335.c b/drivers/rtc/rtc-max31335.c
new file mode 100644
index 000000000..595816973
--- /dev/null
+++ b/drivers/rtc/rtc-max31335.c
@@ -0,0 +1,776 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RTC driver for the MAX31335
+ *
+ * Copyright (C) 2023 Analog Devices
+ *
+ * Antoniu Miclaus <antoniu.miclaus@analog.com>
+ *
+ */
+
+#include <linux/unaligned.h>
+#include <linux/bcd.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/util_macros.h>
+
+/* MAX31335 Register Map */
+#define MAX31335_STATUS1			0x00
+#define MAX31335_INT_EN1			0x01
+#define MAX31335_STATUS2			0x02
+#define MAX31335_INT_EN2			0x03
+#define MAX31335_RTC_RESET			0x04
+#define MAX31335_RTC_CONFIG			0x05
+#define MAX31335_RTC_CONFIG2			0x06
+#define MAX31335_TIMESTAMP_CONFIG		0x07
+#define MAX31335_TIMER_CONFIG			0x08
+#define MAX31335_SECONDS_1_128			0x09
+#define MAX31335_SECONDS			0x0A
+#define MAX31335_MINUTES			0x0B
+#define MAX31335_HOURS				0x0C
+#define MAX31335_DAY				0x0D
+#define MAX31335_DATE				0x0E
+#define MAX31335_MONTH				0x0F
+#define MAX31335_YEAR				0x0F
+#define MAX31335_ALM1_SEC			0x11
+#define MAX31335_ALM1_MIN			0x12
+#define MAX31335_ALM1_HRS			0x13
+#define MAX31335_ALM1_DAY_DATE			0x14
+#define MAX31335_ALM1_MON			0x15
+#define MAX31335_ALM1_YEAR			0x16
+#define MAX31335_ALM2_MIN			0x17
+#define MAX31335_ALM2_HRS			0x18
+#define MAX31335_ALM2_DAY_DATE			0x19
+#define MAX31335_TIMER_COUNT			0x1A
+#define MAX31335_TIMER_INIT			0x1B
+#define MAX31335_PWR_MGMT			0x1C
+#define MAX31335_TRICKLE_REG			0x1D
+#define MAX31335_AGING_OFFSET			0x1E
+#define MAX31335_TS_CONFIG			0x30
+#define MAX31335_TEMP_ALARM_HIGH_MSB		0x31
+#define MAX31335_TEMP_ALARM_HIGH_LSB		0x32
+#define MAX31335_TEMP_ALARM_LOW_MSB		0x33
+#define MAX31335_TEMP_ALARM_LOW_LSB		0x34
+#define MAX31335_TEMP_DATA_MSB			0x35
+#define MAX31335_TEMP_DATA_LSB			0x36
+#define MAX31335_TS0_SEC_1_128			0x40
+#define MAX31335_TS0_SEC			0x41
+#define MAX31335_TS0_MIN			0x42
+#define MAX31335_TS0_HOUR			0x43
+#define MAX31335_TS0_DATE			0x44
+#define MAX31335_TS0_MONTH			0x45
+#define MAX31335_TS0_YEAR			0x46
+#define MAX31335_TS0_FLAGS			0x47
+#define MAX31335_TS1_SEC_1_128			0x48
+#define MAX31335_TS1_SEC			0x49
+#define MAX31335_TS1_MIN			0x4A
+#define MAX31335_TS1_HOUR			0x4B
+#define MAX31335_TS1_DATE			0x4C
+#define MAX31335_TS1_MONTH			0x4D
+#define MAX31335_TS1_YEAR			0x4E
+#define MAX31335_TS1_FLAGS			0x4F
+#define MAX31335_TS2_SEC_1_128			0x50
+#define MAX31335_TS2_SEC			0x51
+#define MAX31335_TS2_MIN			0x52
+#define MAX31335_TS2_HOUR			0x53
+#define MAX31335_TS2_DATE			0x54
+#define MAX31335_TS2_MONTH			0x55
+#define MAX31335_TS2_YEAR			0x56
+#define MAX31335_TS2_FLAGS			0x57
+#define MAX31335_TS3_SEC_1_128			0x58
+#define MAX31335_TS3_SEC			0x59
+#define MAX31335_TS3_MIN			0x5A
+#define MAX31335_TS3_HOUR			0x5B
+#define MAX31335_TS3_DATE			0x5C
+#define MAX31335_TS3_MONTH			0x5D
+#define MAX31335_TS3_YEAR			0x5E
+#define MAX31335_TS3_FLAGS			0x5F
+
+/* MAX31335_STATUS1 Bit Definitions */
+#define MAX31335_STATUS1_PSDECT			BIT(7)
+#define MAX31335_STATUS1_OSF			BIT(6)
+#define MAX31335_STATUS1_PFAIL			BIT(5)
+#define MAX31335_STATUS1_VBATLOW		BIT(4)
+#define MAX31335_STATUS1_DIF			BIT(3)
+#define MAX31335_STATUS1_TIF			BIT(2)
+#define MAX31335_STATUS1_A2F			BIT(1)
+#define MAX31335_STATUS1_A1F			BIT(0)
+
+/* MAX31335_INT_EN1 Bit Definitions */
+#define MAX31335_INT_EN1_DOSF			BIT(6)
+#define MAX31335_INT_EN1_PFAILE			BIT(5)
+#define MAX31335_INT_EN1_VBATLOWE		BIT(4)
+#define MAX31335_INT_EN1_DIE			BIT(3)
+#define MAX31335_INT_EN1_TIE			BIT(2)
+#define MAX31335_INT_EN1_A2IE			BIT(1)
+#define MAX31335_INT_EN1_A1IE			BIT(0)
+
+/* MAX31335_STATUS2 Bit Definitions */
+#define MAX31335_STATUS2_TEMP_RDY		BIT(2)
+#define MAX31335_STATUS2_OTF			BIT(1)
+#define MAX31335_STATUS2_UTF			BIT(0)
+
+/* MAX31335_INT_EN2 Bit Definitions */
+#define MAX31335_INT_EN2_TEMP_RDY_EN		BIT(2)
+#define MAX31335_INT_EN2_OTIE			BIT(1)
+#define MAX31335_INT_EN2_UTIE			BIT(0)
+
+/* MAX31335_RTC_RESET Bit Definitions */
+#define MAX31335_RTC_RESET_SWRST		BIT(0)
+
+/* MAX31335_RTC_CONFIG1 Bit Definitions */
+#define MAX31335_RTC_CONFIG1_EN_IO		BIT(6)
+#define MAX31335_RTC_CONFIG1_A1AC		GENMASK(5, 4)
+#define MAX31335_RTC_CONFIG1_DIP		BIT(3)
+#define MAX31335_RTC_CONFIG1_I2C_TIMEOUT	BIT(1)
+#define MAX31335_RTC_CONFIG1_EN_OSC		BIT(0)
+
+/* MAX31335_RTC_CONFIG2 Bit Definitions */
+#define MAX31335_RTC_CONFIG2_ENCLKO		BIT(2)
+#define MAX31335_RTC_CONFIG2_CLKO_HZ		GENMASK(1, 0)
+
+/* MAX31335_TIMESTAMP_CONFIG Bit Definitions */
+#define MAX31335_TIMESTAMP_CONFIG_TSVLOW	BIT(5)
+#define MAX31335_TIMESTAMP_CONFIG_TSPWM		BIT(4)
+#define MAX31335_TIMESTAMP_CONFIG_TSDIN		BIT(3)
+#define MAX31335_TIMESTAMP_CONFIG_TSOW		BIT(2)
+#define MAX31335_TIMESTAMP_CONFIG_TSR		BIT(1)
+#define MAX31335_TIMESTAMP_CONFIG_TSE		BIT(0)
+
+/* MAX31335_TIMER_CONFIG Bit Definitions */
+#define MAX31335_TIMER_CONFIG_TE		BIT(4)
+#define MAX31335_TIMER_CONFIG_TPAUSE		BIT(3)
+#define MAX31335_TIMER_CONFIG_TRPT		BIT(2)
+#define MAX31335_TIMER_CONFIG_TFS		GENMASK(1, 0)
+
+/* MAX31335_HOURS Bit Definitions */
+#define MAX31335_HOURS_F_24_12			BIT(6)
+#define MAX31335_HOURS_HR_20_AM_PM		BIT(5)
+
+/* MAX31335_MONTH Bit Definitions */
+#define MAX31335_MONTH_CENTURY			BIT(7)
+
+/* MAX31335_PWR_MGMT Bit Definitions */
+#define MAX31335_PWR_MGMT_PFVT			BIT(0)
+
+/* MAX31335_TRICKLE_REG Bit Definitions */
+#define MAX31335_TRICKLE_REG_TRICKLE		GENMASK(3, 1)
+#define MAX31335_TRICKLE_REG_EN_TRICKLE		BIT(0)
+
+/* MAX31335_TS_CONFIG Bit Definitions */
+#define MAX31335_TS_CONFIG_AUTO			BIT(4)
+#define MAX31335_TS_CONFIG_CONVERT_T		BIT(3)
+#define MAX31335_TS_CONFIG_TSINT		GENMASK(2, 0)
+
+/* MAX31335_TS_FLAGS Bit Definitions */
+#define MAX31335_TS_FLAGS_VLOWF			BIT(3)
+#define MAX31335_TS_FLAGS_VBATF			BIT(2)
+#define MAX31335_TS_FLAGS_VCCF			BIT(1)
+#define MAX31335_TS_FLAGS_DINF			BIT(0)
+
+/* MAX31335 Miscellaneous Definitions */
+#define MAX31335_TRICKLE_SCHOTTKY_DIODE		1
+#define MAX31335_TRICKLE_STANDARD_DIODE		4
+#define MAX31335_RAM_SIZE			32
+#define MAX31335_TIME_SIZE			0x07
+
+/* MAX31331 Register Map */
+#define MAX31331_RTC_CONFIG2			0x04
+
+#define clk_hw_to_max31335(_hw) container_of(_hw, struct max31335_data, clkout)
+
+/* Supported Maxim RTC */
+enum max_rtc_ids {
+	ID_MAX31331,
+	ID_MAX31335,
+	MAX_RTC_ID_NR
+};
+
+struct chip_desc {
+	u8 sec_reg;
+	u8 alarm1_sec_reg;
+
+	u8 int_en_reg;
+	u8 int_status_reg;
+
+	u8 ram_reg;
+	u8 ram_size;
+
+	u8 temp_reg;
+
+	u8 trickle_reg;
+
+	u8 clkout_reg;
+
+	enum max_rtc_ids id;
+};
+
+struct max31335_data {
+	struct regmap *regmap;
+	struct rtc_device *rtc;
+	struct clk_hw clkout;
+	struct clk *clkin;
+	const struct chip_desc *chip;
+	int irq;
+};
+
+static const int max31335_clkout_freq[] = { 1, 64, 1024, 32768 };
+
+static const struct chip_desc chip[MAX_RTC_ID_NR] = {
+	[ID_MAX31331] = {
+		.id = ID_MAX31331,
+		.int_en_reg = 0x01,
+		.int_status_reg = 0x00,
+		.sec_reg = 0x08,
+		.alarm1_sec_reg = 0x0F,
+		.ram_reg = 0x20,
+		.ram_size = 32,
+		.trickle_reg = 0x1B,
+		.clkout_reg = 0x04,
+	},
+	[ID_MAX31335] = {
+		.id = ID_MAX31335,
+		.int_en_reg = 0x01,
+		.int_status_reg = 0x00,
+		.sec_reg = 0x0A,
+		.alarm1_sec_reg = 0x11,
+		.ram_reg = 0x40,
+		.ram_size = 32,
+		.temp_reg = 0x35,
+		.trickle_reg = 0x1D,
+		.clkout_reg = 0x06,
+	},
+};
+
+static const u16 max31335_trickle_resistors[] = {3000, 6000, 11000};
+
+static bool max31335_volatile_reg(struct device *dev, unsigned int reg)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	const struct chip_desc *chip = max31335->chip;
+
+	/* time keeping registers */
+	if (reg >= chip->sec_reg && reg < chip->sec_reg + MAX31335_TIME_SIZE)
+		return true;
+
+	/* interrupt status register */
+	if (reg == chip->int_status_reg)
+		return true;
+
+	/* temperature registers if valid */
+	if (chip->temp_reg && (reg == chip->temp_reg || reg == chip->temp_reg + 1))
+		return true;
+
+	return false;
+}
+
+static const struct regmap_config regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0x5F,
+	.volatile_reg = max31335_volatile_reg,
+};
+
+static int max31335_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	u8 date[7];
+	int ret;
+
+	ret = regmap_bulk_read(max31335->regmap, max31335->chip->sec_reg, date,
+			       sizeof(date));
+	if (ret)
+		return ret;
+
+	tm->tm_sec  = bcd2bin(date[0] & 0x7f);
+	tm->tm_min  = bcd2bin(date[1] & 0x7f);
+	tm->tm_hour = bcd2bin(date[2] & 0x3f);
+	tm->tm_wday = bcd2bin(date[3] & 0x7) - 1;
+	tm->tm_mday = bcd2bin(date[4] & 0x3f);
+	tm->tm_mon  = bcd2bin(date[5] & 0x1f) - 1;
+	tm->tm_year = bcd2bin(date[6]) + 100;
+
+	if (FIELD_GET(MAX31335_MONTH_CENTURY, date[5]))
+		tm->tm_year += 100;
+
+	return 0;
+}
+
+static int max31335_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	u8 date[7];
+
+	date[0] = bin2bcd(tm->tm_sec);
+	date[1] = bin2bcd(tm->tm_min);
+	date[2] = bin2bcd(tm->tm_hour);
+	date[3] = bin2bcd(tm->tm_wday + 1);
+	date[4] = bin2bcd(tm->tm_mday);
+	date[5] = bin2bcd(tm->tm_mon + 1);
+	date[6] = bin2bcd(tm->tm_year % 100);
+
+	if (tm->tm_year >= 200)
+		date[5] |= FIELD_PREP(MAX31335_MONTH_CENTURY, 1);
+
+	return regmap_bulk_write(max31335->regmap, max31335->chip->sec_reg, date,
+				 sizeof(date));
+}
+
+static int max31335_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	int ret, ctrl, status;
+	struct rtc_time time;
+	u8 regs[6];
+
+	ret = regmap_bulk_read(max31335->regmap, max31335->chip->alarm1_sec_reg, regs,
+			       sizeof(regs));
+	if (ret)
+		return ret;
+
+	alrm->time.tm_sec  = bcd2bin(regs[0] & 0x7f);
+	alrm->time.tm_min  = bcd2bin(regs[1] & 0x7f);
+	alrm->time.tm_hour = bcd2bin(regs[2] & 0x3f);
+	alrm->time.tm_mday = bcd2bin(regs[3] & 0x3f);
+	alrm->time.tm_mon  = bcd2bin(regs[4] & 0x1f) - 1;
+	alrm->time.tm_year = bcd2bin(regs[5]) + 100;
+
+	ret = max31335_read_time(dev, &time);
+	if (ret)
+		return ret;
+
+	if (time.tm_year >= 200)
+		alrm->time.tm_year += 100;
+
+	ret = regmap_read(max31335->regmap, max31335->chip->int_en_reg, &ctrl);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(max31335->regmap, max31335->chip->int_status_reg, &status);
+	if (ret)
+		return ret;
+
+	alrm->enabled = FIELD_GET(MAX31335_INT_EN1_A1IE, ctrl);
+	alrm->pending = FIELD_GET(MAX31335_STATUS1_A1F, status);
+
+	return 0;
+}
+
+static int max31335_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	unsigned int reg;
+	u8 regs[6];
+	int ret;
+
+	regs[0] = bin2bcd(alrm->time.tm_sec);
+	regs[1] = bin2bcd(alrm->time.tm_min);
+	regs[2] = bin2bcd(alrm->time.tm_hour);
+	regs[3] = bin2bcd(alrm->time.tm_mday);
+	regs[4] = bin2bcd(alrm->time.tm_mon + 1);
+	regs[5] = bin2bcd(alrm->time.tm_year % 100);
+
+	ret = regmap_bulk_write(max31335->regmap, max31335->chip->alarm1_sec_reg,
+				regs, sizeof(regs));
+	if (ret)
+		return ret;
+
+	reg = FIELD_PREP(MAX31335_INT_EN1_A1IE, alrm->enabled);
+	ret = regmap_update_bits(max31335->regmap, max31335->chip->int_en_reg,
+				 MAX31335_INT_EN1_A1IE, reg);
+	if (ret)
+		return ret;
+
+	return regmap_update_bits(max31335->regmap, max31335->chip->int_status_reg,
+				  MAX31335_STATUS1_A1F, 0);
+}
+
+static int max31335_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+
+	return regmap_update_bits(max31335->regmap, max31335->chip->int_en_reg,
+				  MAX31335_INT_EN1_A1IE, enabled);
+}
+
+static irqreturn_t max31335_handle_irq(int irq, void *dev_id)
+{
+	struct max31335_data *max31335 = dev_id;
+	struct mutex *lock = &max31335->rtc->ops_lock;
+	int ret, status;
+
+	mutex_lock(lock);
+
+	ret = regmap_read(max31335->regmap, max31335->chip->int_status_reg, &status);
+	if (ret)
+		goto exit;
+
+	if (FIELD_GET(MAX31335_STATUS1_A1F, status)) {
+		ret = regmap_update_bits(max31335->regmap, max31335->chip->int_status_reg,
+					 MAX31335_STATUS1_A1F, 0);
+		if (ret)
+			goto exit;
+
+		rtc_update_irq(max31335->rtc, 1, RTC_AF | RTC_IRQF);
+	}
+
+exit:
+	mutex_unlock(lock);
+
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops max31335_rtc_ops = {
+	.read_time = max31335_read_time,
+	.set_time = max31335_set_time,
+	.read_alarm = max31335_read_alarm,
+	.set_alarm = max31335_set_alarm,
+	.alarm_irq_enable = max31335_alarm_irq_enable,
+};
+
+static int max31335_trickle_charger_setup(struct device *dev,
+					  struct max31335_data *max31335)
+{
+	u32 ohms, chargeable;
+	int i, trickle_cfg;
+	const char *diode;
+
+	if (device_property_read_u32(dev, "aux-voltage-chargeable",
+				     &chargeable))
+		return 0;
+
+	if (device_property_read_u32(dev, "trickle-resistor-ohms", &ohms))
+		return 0;
+
+	if (device_property_read_string(dev, "adi,tc-diode", &diode))
+		return 0;
+
+	if (!strcmp(diode, "schottky"))
+		trickle_cfg = MAX31335_TRICKLE_SCHOTTKY_DIODE;
+	else if (!strcmp(diode, "standard+schottky"))
+		trickle_cfg = MAX31335_TRICKLE_STANDARD_DIODE;
+	else
+		return dev_err_probe(dev, -EINVAL,
+				     "Invalid tc-diode value: %s\n", diode);
+
+	for (i = 0; i < ARRAY_SIZE(max31335_trickle_resistors); i++)
+		if (ohms == max31335_trickle_resistors[i])
+			break;
+
+	if (i >= ARRAY_SIZE(max31335_trickle_resistors))
+		return 0;
+
+	i = i + trickle_cfg;
+
+	return regmap_write(max31335->regmap, max31335->chip->trickle_reg,
+			    FIELD_PREP(MAX31335_TRICKLE_REG_TRICKLE, i) |
+			    FIELD_PREP(MAX31335_TRICKLE_REG_EN_TRICKLE,
+				       chargeable));
+}
+
+static unsigned long max31335_clkout_recalc_rate(struct clk_hw *hw,
+						 unsigned long parent_rate)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+	unsigned int freq_mask;
+	unsigned int reg;
+	int ret;
+
+	ret = regmap_read(max31335->regmap, max31335->chip->clkout_reg, &reg);
+	if (ret)
+		return 0;
+
+	freq_mask = __roundup_pow_of_two(ARRAY_SIZE(max31335_clkout_freq)) - 1;
+
+	return max31335_clkout_freq[reg & freq_mask];
+}
+
+static int max31335_clkout_determine_rate(struct clk_hw *hw,
+					  struct clk_rate_request *req)
+{
+	int index;
+
+	index = find_closest(req->rate, max31335_clkout_freq,
+			     ARRAY_SIZE(max31335_clkout_freq));
+
+	req->rate = max31335_clkout_freq[index];
+
+	return 0;
+}
+
+static int max31335_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+				    unsigned long parent_rate)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+	unsigned int freq_mask;
+	int index;
+
+	index = find_closest(rate, max31335_clkout_freq,
+			     ARRAY_SIZE(max31335_clkout_freq));
+	freq_mask = __roundup_pow_of_two(ARRAY_SIZE(max31335_clkout_freq)) - 1;
+
+	return regmap_update_bits(max31335->regmap, max31335->chip->clkout_reg,
+				 freq_mask, index);
+}
+
+static int max31335_clkout_enable(struct clk_hw *hw)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+
+	return regmap_set_bits(max31335->regmap, max31335->chip->clkout_reg,
+			      MAX31335_RTC_CONFIG2_ENCLKO);
+}
+
+static void max31335_clkout_disable(struct clk_hw *hw)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+
+	regmap_clear_bits(max31335->regmap, max31335->chip->clkout_reg,
+			  MAX31335_RTC_CONFIG2_ENCLKO);
+}
+
+static int max31335_clkout_is_enabled(struct clk_hw *hw)
+{
+	struct max31335_data *max31335 = clk_hw_to_max31335(hw);
+	unsigned int reg;
+	int ret;
+
+	ret = regmap_read(max31335->regmap, max31335->chip->clkout_reg, &reg);
+	if (ret)
+		return ret;
+
+	return !!(reg & MAX31335_RTC_CONFIG2_ENCLKO);
+}
+
+static const struct clk_ops max31335_clkout_ops = {
+	.recalc_rate = max31335_clkout_recalc_rate,
+	.determine_rate = max31335_clkout_determine_rate,
+	.set_rate = max31335_clkout_set_rate,
+	.enable = max31335_clkout_enable,
+	.disable = max31335_clkout_disable,
+	.is_enabled = max31335_clkout_is_enabled,
+};
+
+static struct clk_init_data max31335_clk_init = {
+	.name = "max31335-clkout",
+	.ops = &max31335_clkout_ops,
+};
+
+static int max31335_nvmem_reg_read(void *priv, unsigned int offset,
+				   void *val, size_t bytes)
+{
+	struct max31335_data *max31335 = priv;
+	unsigned int reg = max31335->chip->ram_reg + offset;
+
+	return regmap_bulk_read(max31335->regmap, reg, val, bytes);
+}
+
+static int max31335_nvmem_reg_write(void *priv, unsigned int offset,
+				    void *val, size_t bytes)
+{
+	struct max31335_data *max31335 = priv;
+	unsigned int reg = max31335->chip->ram_reg + offset;
+
+	return regmap_bulk_write(max31335->regmap, reg, val, bytes);
+}
+
+static struct nvmem_config max31335_nvmem_cfg = {
+	.reg_read = max31335_nvmem_reg_read,
+	.reg_write = max31335_nvmem_reg_write,
+	.word_size = 8,
+	.size = MAX31335_RAM_SIZE,
+};
+
+#if IS_REACHABLE(CONFIG_HWMON)
+static int max31335_read_temp(struct device *dev, enum hwmon_sensor_types type,
+			      u32 attr, int channel, long *val)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	u8 reg[2];
+	s16 temp;
+	int ret;
+
+	if (type != hwmon_temp || attr != hwmon_temp_input)
+		return -EOPNOTSUPP;
+
+	ret = regmap_bulk_read(max31335->regmap, max31335->chip->temp_reg,
+			       reg, 2);
+	if (ret)
+		return ret;
+
+	temp = get_unaligned_be16(reg);
+
+	*val = (temp / 64) * 250;
+
+	return 0;
+}
+
+static umode_t max31335_is_visible(const void *data,
+				   enum hwmon_sensor_types type,
+				   u32 attr, int channel)
+{
+	if (type == hwmon_temp && attr == hwmon_temp_input)
+		return 0444;
+
+	return 0;
+}
+
+static const struct hwmon_channel_info *max31335_info[] = {
+	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
+	NULL
+};
+
+static const struct hwmon_ops max31335_hwmon_ops = {
+	.is_visible = max31335_is_visible,
+	.read = max31335_read_temp,
+};
+
+static const struct hwmon_chip_info max31335_chip_info = {
+	.ops = &max31335_hwmon_ops,
+	.info = max31335_info,
+};
+#endif
+
+static int max31335_clkout_register(struct device *dev)
+{
+	struct max31335_data *max31335 = dev_get_drvdata(dev);
+	int ret;
+
+	if (!device_property_present(dev, "#clock-cells"))
+		return regmap_clear_bits(max31335->regmap, max31335->chip->clkout_reg,
+				  MAX31335_RTC_CONFIG2_ENCLKO);
+
+	max31335->clkout.init = &max31335_clk_init;
+
+	ret = devm_clk_hw_register(dev, &max31335->clkout);
+	if (ret)
+		return dev_err_probe(dev, ret, "cannot register clock\n");
+
+	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+					  &max31335->clkout);
+	if (ret)
+		return dev_err_probe(dev, ret, "cannot add hw provider\n");
+
+	max31335->clkout.clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(max31335->clkout.clk))
+		return dev_err_probe(dev, PTR_ERR(max31335->clkout.clk),
+				     "cannot enable clkout\n");
+
+	return 0;
+}
+
+static int max31335_probe(struct i2c_client *client)
+{
+	struct max31335_data *max31335;
+#if IS_REACHABLE(CONFIG_HWMON)
+	struct device *hwmon;
+#endif
+	const struct chip_desc *match;
+	int ret;
+
+	max31335 = devm_kzalloc(&client->dev, sizeof(*max31335), GFP_KERNEL);
+	if (!max31335)
+		return -ENOMEM;
+
+	max31335->regmap = devm_regmap_init_i2c(client, &regmap_config);
+	if (IS_ERR(max31335->regmap))
+		return PTR_ERR(max31335->regmap);
+
+	i2c_set_clientdata(client, max31335);
+	match = i2c_get_match_data(client);
+	if (!match)
+		return -ENODEV;
+	max31335->chip = match;
+	max31335->rtc = devm_rtc_allocate_device(&client->dev);
+	if (IS_ERR(max31335->rtc))
+		return PTR_ERR(max31335->rtc);
+
+	max31335->rtc->ops = &max31335_rtc_ops;
+	max31335->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	max31335->rtc->range_max = RTC_TIMESTAMP_END_2199;
+	max31335->rtc->alarm_offset_max = 24 * 60 * 60;
+
+	ret = max31335_clkout_register(&client->dev);
+	if (ret)
+		return ret;
+
+	if (client->irq > 0) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						NULL, max31335_handle_irq,
+						IRQF_ONESHOT,
+						"max31335", max31335);
+		if (ret) {
+			dev_warn(&client->dev,
+				 "unable to request IRQ, alarm max31335 disabled\n");
+			client->irq = 0;
+		} else {
+			max31335->irq = client->irq;
+		}
+	}
+
+	if (!client->irq)
+		clear_bit(RTC_FEATURE_ALARM, max31335->rtc->features);
+
+	max31335_nvmem_cfg.priv = max31335;
+	ret = devm_rtc_nvmem_register(max31335->rtc, &max31335_nvmem_cfg);
+	if (ret)
+		return dev_err_probe(&client->dev, ret,
+				     "cannot register rtc nvmem\n");
+
+#if IS_REACHABLE(CONFIG_HWMON)
+	if (max31335->chip->temp_reg) {
+		hwmon = devm_hwmon_device_register_with_info(&client->dev, client->name, max31335,
+							     &max31335_chip_info, NULL);
+		if (IS_ERR(hwmon))
+			return dev_err_probe(&client->dev, PTR_ERR(hwmon),
+					     "cannot register hwmon device\n");
+	}
+#endif
+
+	ret = max31335_trickle_charger_setup(&client->dev, max31335);
+	if (ret)
+		return ret;
+
+	return devm_rtc_register_device(max31335->rtc);
+}
+
+static const struct i2c_device_id max31335_id[] = {
+	{ .name = "max31331", .driver_data = (kernel_ulong_t)&chip[ID_MAX31331] },
+	{ .name = "max31335", .driver_data = (kernel_ulong_t)&chip[ID_MAX31335] },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, max31335_id);
+
+static const struct of_device_id max31335_of_match[] = {
+	{ .compatible = "adi,max31331", .data = &chip[ID_MAX31331] },
+	{ .compatible = "adi,max31335", .data = &chip[ID_MAX31335] },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, max31335_of_match);
+
+static struct i2c_driver max31335_driver = {
+	.driver = {
+		.name = "rtc-max31335",
+		.of_match_table = max31335_of_match,
+	},
+	.probe = max31335_probe,
+	.id_table = max31335_id,
+};
+module_i2c_driver(max31335_driver);
+
+MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com>");
+MODULE_AUTHOR("Saket Kumar Purwar <Saket.Kumarpurwar@analog.com>");
+MODULE_DESCRIPTION("MAX31335 RTC driver");
+MODULE_LICENSE("GPL");