Merge tag 'timers-core-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "A rather large update for timekeeping and timers:

   - The final step to get rid of auto-rearming posix-timers

     posix-timers are currently auto-rearmed by the kernel when the
     signal of the timer is ignored so that the timer signal can be
     delivered once the corresponding signal is unignored.

     This requires to throttle the timer to prevent a DoS by small
     intervals and keeps the system pointlessly out of low power states
     for no value. This is a long standing non-trivial problem due to
     the lock order of posix-timer lock and the sighand lock along with
     life time issues as the timer and the sigqueue have different life
     time rules.

     Cure this by:

       - Embedding the sigqueue into the timer struct to have the same
         life time rules. Aside of that this also avoids the lookup of
         the timer in the signal delivery and rearm path as it's just a
         always valid container_of() now.

       - Queuing ignored timer signals onto a seperate ignored list.

       - Moving queued timer signals onto the ignored list when the
         signal is switched to SIG_IGN before it could be delivered.

       - Walking the ignored list when SIG_IGN is lifted and requeue the
         signals to the actual signal lists. This allows the signal
         delivery code to rearm the timer.

     This also required to consolidate the signal delivery rules so they
     are consistent across all situations. With that all self test
     scenarios finally succeed.

   - Core infrastructure for VFS multigrain timestamping

     This is required to allow the kernel to use coarse grained time
     stamps by default and switch to fine grained time stamps when inode
     attributes are actively observed via getattr().

     These changes have been provided to the VFS tree as well, so that
     the VFS specific infrastructure could be built on top.

   - Cleanup and consolidation of the sleep() infrastructure

       - Move all sleep and timeout functions into one file

       - Rework udelay() and ndelay() into proper documented inline
         functions and replace the hardcoded magic numbers by proper
         defines.

       - Rework the fsleep() implementation to take the reality of the
         timer wheel granularity on different HZ values into account.
         Right now the boundaries are hard coded time ranges which fail
         to provide the requested accuracy on different HZ settings.

       - Update documentation for all sleep/timeout related functions
         and fix up stale documentation links all over the place

       - Fixup a few usage sites

   - Rework of timekeeping and adjtimex(2) to prepare for multiple PTP
     clocks

     A system can have multiple PTP clocks which are participating in
     seperate and independent PTP clock domains. So far the kernel only
     considers the PTP clock which is based on CLOCK TAI relevant as
     that's the clock which drives the timekeeping adjustments via the
     various user space daemons through adjtimex(2).

     The non TAI based clock domains are accessible via the file
     descriptor based posix clocks, but their usability is very limited.
     They can't be accessed fast as they always go all the way out to
     the hardware and they cannot be utilized in the kernel itself.

     As Time Sensitive Networking (TSN) gains traction it is required to
     provide fast user and kernel space access to these clocks.

     The approach taken is to utilize the timekeeping and adjtimex(2)
     infrastructure to provide this access in a similar way how the
     kernel provides access to clock MONOTONIC, REALTIME etc.

     Instead of creating a duplicated infrastructure this rework
     converts timekeeping and adjtimex(2) into generic functionality
     which operates on pointers to data structures instead of using
     static variables.

     This allows to provide time accessors and adjtimex(2) functionality
     for the independent PTP clocks in a subsequent step.

   - Consolidate hrtimer initialization

     hrtimers are set up by initializing the data structure and then
     seperately setting the callback function for historical reasons.

     That's an extra unnecessary step and makes Rust support less
     straight forward than it should be.

     Provide a new set of hrtimer_setup*() functions and convert the
     core code and a few usage sites of the less frequently used
     interfaces over.

     The bulk of the htimer_init() to hrtimer_setup() conversion is
     already prepared and scheduled for the next merge window.

   - Drivers:

       - Ensure that the global timekeeping clocksource is utilizing the
         cluster 0 timer on MIPS multi-cluster systems.

         Otherwise CPUs on different clusters use their cluster specific
         clocksource which is not guaranteed to be synchronized with
         other clusters.

       - Mostly boring cleanups, fixes, improvements and code movement"

* tag 'timers-core-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (140 commits)
  posix-timers: Fix spurious warning on double enqueue versus do_exit()
  clocksource/drivers/arm_arch_timer: Use of_property_present() for non-boolean properties
  clocksource/drivers/gpx: Remove redundant casts
  clocksource/drivers/timer-ti-dm: Fix child node refcount handling
  dt-bindings: timer: actions,owl-timer: convert to YAML
  clocksource/drivers/ralink: Add Ralink System Tick Counter driver
  clocksource/drivers/mips-gic-timer: Always use cluster 0 counter as clocksource
  clocksource/drivers/timer-ti-dm: Don't fail probe if int not found
  clocksource/drivers:sp804: Make user selectable
  clocksource/drivers/dw_apb: Remove unused dw_apb_clockevent functions
  hrtimers: Delete hrtimer_init_on_stack()
  alarmtimer: Switch to use hrtimer_setup() and hrtimer_setup_on_stack()
  io_uring: Switch to use hrtimer_setup_on_stack()
  sched/idle: Switch to use hrtimer_setup_on_stack()
  hrtimers: Delete hrtimer_init_sleeper_on_stack()
  wait: Switch to use hrtimer_setup_sleeper_on_stack()
  timers: Switch to use hrtimer_setup_sleeper_on_stack()
  net: pktgen: Switch to use hrtimer_setup_sleeper_on_stack()
  futex: Switch to use hrtimer_setup_sleeper_on_stack()
  fs/aio: Switch to use hrtimer_setup_sleeper_on_stack()
  ...

18 files changed, 226 insertions, 81 deletions

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 95dd4660b5b6..487c85259967 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -400,7 +400,8 @@ config ARM_GT_INITIAL_PRESCALER_VAL
 	  This affects CPU_FREQ max delta from the initial frequency.
 
 config ARM_TIMER_SP804
-	bool "Support for Dual Timer SP804 module" if COMPILE_TEST
+	bool "Support for Dual Timer SP804 module"
+	depends on ARM || ARM64 || COMPILE_TEST
 	depends on GENERIC_SCHED_CLOCK && HAVE_CLK
 	select CLKSRC_MMIO
 	select TIMER_OF if OF
@@ -753,4 +754,13 @@ config EP93XX_TIMER
 	  Enables support for the Cirrus Logic timer block
 	  EP93XX.
 
+config RALINK_TIMER
+	bool "Ralink System Tick Counter"
+	depends on SOC_RT305X || SOC_MT7620 || COMPILE_TEST
+	select CLKSRC_MMIO
+	select TIMER_OF
+	help
+	  Enables support for system tick counter present on
+	  Ralink SoCs RT3352 and MT7620.
+
 endmenu
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 22743785299e..43ef16a4efa6 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -91,3 +91,4 @@ obj-$(CONFIG_GOLDFISH_TIMER)		+= timer-goldfish.o
 obj-$(CONFIG_GXP_TIMER)			+= timer-gxp.o
 obj-$(CONFIG_CLKSRC_LOONGSON1_PWM)	+= timer-loongson1-pwm.o
 obj-$(CONFIG_EP93XX_TIMER)		+= timer-ep93xx.o
+obj-$(CONFIG_RALINK_TIMER)		+= timer-ralink.o
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 03733101e231..808f259781fd 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1179,8 +1179,6 @@ static void arch_timer_stop(struct clock_event_device *clk)
 	disable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi]);
 	if (arch_timer_has_nonsecure_ppi())
 		disable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
-
-	clk->set_state_shutdown(clk);
 }
 
 static int arch_timer_dying_cpu(unsigned int cpu)
@@ -1430,7 +1428,7 @@ static int __init arch_timer_of_init(struct device_node *np)
 
 	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
 
-	has_names = of_property_read_bool(np, "interrupt-names");
+	has_names = of_property_present(np, "interrupt-names");
 
 	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++) {
 		if (has_names)
diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c
index a05cfaab5f84..2d86bbc2764a 100644
--- a/drivers/clocksource/arm_global_timer.c
+++ b/drivers/clocksource/arm_global_timer.c
@@ -195,7 +195,6 @@ static int gt_dying_cpu(unsigned int cpu)
 {
 	struct clock_event_device *clk = this_cpu_ptr(gt_evt);
 
-	gt_clockevent_shutdown(clk);
 	disable_percpu_irq(clk->irq);
 	return 0;
 }
diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c
index f5f24a95ee82..3a55ae5fe225 100644
--- a/drivers/clocksource/dw_apb_timer.c
+++ b/drivers/clocksource/dw_apb_timer.c
@@ -68,25 +68,6 @@ static inline void apbt_writel_relaxed(struct dw_apb_timer *timer, u32 val,
 	writel_relaxed(val, timer->base + offs);
 }
 
-static void apbt_disable_int(struct dw_apb_timer *timer)
-{
-	u32 ctrl = apbt_readl(timer, APBTMR_N_CONTROL);
-
-	ctrl |= APBTMR_CONTROL_INT;
-	apbt_writel(timer, ctrl, APBTMR_N_CONTROL);
-}
-
-/**
- * dw_apb_clockevent_pause() - stop the clock_event_device from running
- *
- * @dw_ced:	The APB clock to stop generating events.
- */
-void dw_apb_clockevent_pause(struct dw_apb_clock_event_device *dw_ced)
-{
-	disable_irq(dw_ced->timer.irq);
-	apbt_disable_int(&dw_ced->timer);
-}
-
 static void apbt_eoi(struct dw_apb_timer *timer)
 {
 	apbt_readl_relaxed(timer, APBTMR_N_EOI);
@@ -285,26 +266,6 @@ dw_apb_clockevent_init(int cpu, const char *name, unsigned rating,
 }
 
 /**
- * dw_apb_clockevent_resume() - resume a clock that has been paused.
- *
- * @dw_ced:	The APB clock to resume.
- */
-void dw_apb_clockevent_resume(struct dw_apb_clock_event_device *dw_ced)
-{
-	enable_irq(dw_ced->timer.irq);
-}
-
-/**
- * dw_apb_clockevent_stop() - stop the clock_event_device and release the IRQ.
- *
- * @dw_ced:	The APB clock to stop generating the events.
- */
-void dw_apb_clockevent_stop(struct dw_apb_clock_event_device *dw_ced)
-{
-	free_irq(dw_ced->timer.irq, &dw_ced->ced);
-}
-
-/**
  * dw_apb_clockevent_register() - register the clock with the generic layer
  *
  * @dw_ced:	The APB clock to register as a clock_event_device.
diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
index ef8cb1b71be4..e6a02e351d77 100644
--- a/drivers/clocksource/exynos_mct.c
+++ b/drivers/clocksource/exynos_mct.c
@@ -496,7 +496,6 @@ static int exynos4_mct_dying_cpu(unsigned int cpu)
 		per_cpu_ptr(&percpu_mct_tick, cpu);
 	struct clock_event_device *evt = &mevt->evt;
 
-	evt->set_state_shutdown(evt);
 	if (mct_int_type == MCT_INT_SPI) {
 		if (evt->irq != -1)
 			disable_irq_nosync(evt->irq);
diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c
index 110347707ff9..7907b740497a 100644
--- a/drivers/clocksource/mips-gic-timer.c
+++ b/drivers/clocksource/mips-gic-timer.c
@@ -166,6 +166,37 @@ static u64 gic_hpt_read(struct clocksource *cs)
 	return gic_read_count();
 }
 
+static u64 gic_hpt_read_multicluster(struct clocksource *cs)
+{
+	unsigned int hi, hi2, lo;
+	u64 count;
+
+	mips_cm_lock_other(0, 0, 0, CM_GCR_Cx_OTHER_BLOCK_GLOBAL);
+
+	if (mips_cm_is64) {
+		count = read_gic_redir_counter();
+		goto out;
+	}
+
+	hi = read_gic_redir_counter_32h();
+	while (true) {
+		lo = read_gic_redir_counter_32l();
+
+		/* If hi didn't change then lo didn't wrap & we're done */
+		hi2 = read_gic_redir_counter_32h();
+		if (hi2 == hi)
+			break;
+
+		/* Otherwise, repeat with the latest hi value */
+		hi = hi2;
+	}
+
+	count = (((u64)hi) << 32) + lo;
+out:
+	mips_cm_unlock_other();
+	return count;
+}
+
 static struct clocksource gic_clocksource = {
 	.name			= "GIC",
 	.read			= gic_hpt_read,
@@ -203,6 +234,11 @@ static int __init __gic_clocksource_init(void)
 		gic_clocksource.rating = 200;
 	gic_clocksource.rating += clamp(gic_frequency / 10000000, 0, 99);
 
+	if (mips_cps_multicluster_cpus()) {
+		gic_clocksource.read = &gic_hpt_read_multicluster;
+		gic_clocksource.vdso_clock_mode = VDSO_CLOCKMODE_NONE;
+	}
+
 	ret = clocksource_register_hz(&gic_clocksource, gic_frequency);
 	if (ret < 0)
 		pr_warn("Unable to register clocksource\n");
@@ -261,7 +297,8 @@ static int __init gic_clocksource_of_init(struct device_node *node)
 	 * stable CPU frequency or on the platforms with CM3 and CPU frequency
 	 * change performed by the CPC core clocks divider.
 	 */
-	if (mips_cm_revision() >= CM_REV_CM3 || !IS_ENABLED(CONFIG_CPU_FREQ)) {
+	if ((mips_cm_revision() >= CM_REV_CM3 || !IS_ENABLED(CONFIG_CPU_FREQ)) &&
+	     !mips_cps_multicluster_cpus()) {
 		sched_clock_register(mips_cm_is64 ?
 				     gic_read_count_64 : gic_read_count_2x32,
 				     gic_count_width, gic_frequency);
diff --git a/drivers/clocksource/timer-armada-370-xp.c b/drivers/clocksource/timer-armada-370-xp.c
index 6ec565d6939a..54284c1c0651 100644
--- a/drivers/clocksource/timer-armada-370-xp.c
+++ b/drivers/clocksource/timer-armada-370-xp.c
@@ -201,7 +201,6 @@ static int armada_370_xp_timer_dying_cpu(unsigned int cpu)
 {
 	struct clock_event_device *evt = per_cpu_ptr(armada_370_xp_evt, cpu);
 
-	evt->set_state_shutdown(evt);
 	disable_percpu_irq(evt->irq);
 	return 0;
 }
diff --git a/drivers/clocksource/timer-gxp.c b/drivers/clocksource/timer-gxp.c
index 57aa2e2cce53..48a73c101eb8 100644
--- a/drivers/clocksource/timer-gxp.c
+++ b/drivers/clocksource/timer-gxp.c
@@ -85,7 +85,7 @@ static int __init gxp_timer_init(struct device_node *node)
 
 	clk = of_clk_get(node, 0);
 	if (IS_ERR(clk)) {
-		ret = (int)PTR_ERR(clk);
+		ret = PTR_ERR(clk);
 		pr_err("%pOFn clock not found: %d\n", node, ret);
 		goto err_free;
 	}
diff --git a/drivers/clocksource/timer-qcom.c b/drivers/clocksource/timer-qcom.c
index eac4c95c6127..ddb1debe6a6b 100644
--- a/drivers/clocksource/timer-qcom.c
+++ b/drivers/clocksource/timer-qcom.c
@@ -130,7 +130,6 @@ static int msm_local_timer_dying_cpu(unsigned int cpu)
 {
 	struct clock_event_device *evt = per_cpu_ptr(msm_evt, cpu);
 
-	evt->set_state_shutdown(evt);
 	disable_percpu_irq(evt->irq);
 	return 0;
 }
diff --git a/drivers/clocksource/timer-ralink.c b/drivers/clocksource/timer-ralink.c
new file mode 100644
index 000000000000..6ecdb4228f76
--- /dev/null
+++ b/drivers/clocksource/timer-ralink.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ralink System Tick Counter driver present on RT3352 and MT7620 SoCs.
+ *
+ * Copyright (C) 2013 by John Crispin <john@phrozen.org>
+ */
+
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/reset.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+#define SYSTICK_FREQ		(50 * 1000)
+
+#define SYSTICK_CONFIG		0x00
+#define SYSTICK_COMPARE		0x04
+#define SYSTICK_COUNT		0x08
+
+/* route systick irq to mips irq 7 instead of the r4k-timer */
+#define CFG_EXT_STK_EN		0x2
+/* enable the counter */
+#define CFG_CNT_EN		0x1
+
+struct systick_device {
+	void __iomem *membase;
+	struct clock_event_device dev;
+	int irq_requested;
+	int freq_scale;
+};
+
+static int systick_set_oneshot(struct clock_event_device *evt);
+static int systick_shutdown(struct clock_event_device *evt);
+
+static int systick_next_event(unsigned long delta,
+			      struct clock_event_device *evt)
+{
+	struct systick_device *sdev;
+	u32 count;
+
+	sdev = container_of(evt, struct systick_device, dev);
+	count = ioread32(sdev->membase + SYSTICK_COUNT);
+	count = (count + delta) % SYSTICK_FREQ;
+	iowrite32(count, sdev->membase + SYSTICK_COMPARE);
+
+	return 0;
+}
+
+static void systick_event_handler(struct clock_event_device *dev)
+{
+	/* noting to do here */
+}
+
+static irqreturn_t systick_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *dev = (struct clock_event_device *)dev_id;
+
+	dev->event_handler(dev);
+
+	return IRQ_HANDLED;
+}
+
+static struct systick_device systick = {
+	.dev = {
+		/*
+		 * cevt-r4k uses 300, make sure systick
+		 * gets used if available
+		 */
+		.rating			= 310,
+		.features		= CLOCK_EVT_FEAT_ONESHOT,
+		.set_next_event		= systick_next_event,
+		.set_state_shutdown	= systick_shutdown,
+		.set_state_oneshot	= systick_set_oneshot,
+		.event_handler		= systick_event_handler,
+	},
+};
+
+static int systick_shutdown(struct clock_event_device *evt)
+{
+	struct systick_device *sdev;
+
+	sdev = container_of(evt, struct systick_device, dev);
+
+	if (sdev->irq_requested)
+		free_irq(systick.dev.irq, &systick.dev);
+	sdev->irq_requested = 0;
+	iowrite32(0, systick.membase + SYSTICK_CONFIG);
+
+	return 0;
+}
+
+static int systick_set_oneshot(struct clock_event_device *evt)
+{
+	const char *name = systick.dev.name;
+	struct systick_device *sdev;
+	int irq = systick.dev.irq;
+
+	sdev = container_of(evt, struct systick_device, dev);
+
+	if (!sdev->irq_requested) {
+		if (request_irq(irq, systick_interrupt,
+				IRQF_PERCPU | IRQF_TIMER, name, &systick.dev))
+			pr_err("Failed to request irq %d (%s)\n", irq, name);
+	}
+	sdev->irq_requested = 1;
+	iowrite32(CFG_EXT_STK_EN | CFG_CNT_EN,
+		  systick.membase + SYSTICK_CONFIG);
+
+	return 0;
+}
+
+static int __init ralink_systick_init(struct device_node *np)
+{
+	int ret;
+
+	systick.membase = of_iomap(np, 0);
+	if (!systick.membase)
+		return -ENXIO;
+
+	systick.dev.name = np->name;
+	clockevents_calc_mult_shift(&systick.dev, SYSTICK_FREQ, 60);
+	systick.dev.max_delta_ns = clockevent_delta2ns(0x7fff, &systick.dev);
+	systick.dev.max_delta_ticks = 0x7fff;
+	systick.dev.min_delta_ns = clockevent_delta2ns(0x3, &systick.dev);
+	systick.dev.min_delta_ticks = 0x3;
+	systick.dev.irq = irq_of_parse_and_map(np, 0);
+	if (!systick.dev.irq) {
+		pr_err("%pOFn: request_irq failed", np);
+		return -EINVAL;
+	}
+
+	ret = clocksource_mmio_init(systick.membase + SYSTICK_COUNT, np->name,
+				    SYSTICK_FREQ, 301, 16,
+				    clocksource_mmio_readl_up);
+	if (ret)
+		return ret;
+
+	clockevents_register_device(&systick.dev);
+
+	pr_info("%pOFn: running - mult: %d, shift: %d\n",
+			np, systick.dev.mult, systick.dev.shift);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(systick, "ralink,cevt-systick", ralink_systick_init);
diff --git a/drivers/clocksource/timer-tegra.c b/drivers/clocksource/timer-tegra.c
index e9635c25eef4..35b6ce9deffa 100644
--- a/drivers/clocksource/timer-tegra.c
+++ b/drivers/clocksource/timer-tegra.c
@@ -158,7 +158,6 @@ static int tegra_timer_stop(unsigned int cpu)
 {
 	struct timer_of *to = per_cpu_ptr(&tegra_to, cpu);
 
-	to->clkevt.set_state_shutdown(&to->clkevt);
 	disable_irq_nosync(to->clkevt.irq);
 
 	return 0;
diff --git a/drivers/clocksource/timer-ti-dm-systimer.c b/drivers/clocksource/timer-ti-dm-systimer.c
index c2dcd8d68e45..985a6d08512b 100644
--- a/drivers/clocksource/timer-ti-dm-systimer.c
+++ b/drivers/clocksource/timer-ti-dm-systimer.c
@@ -202,10 +202,10 @@ static bool __init dmtimer_is_preferred(struct device_node *np)
 
 	/* Secure gptimer12 is always clocked with a fixed source */
 	if (!of_property_read_bool(np, "ti,timer-secure")) {
-		if (!of_property_read_bool(np, "assigned-clocks"))
+		if (!of_property_present(np, "assigned-clocks"))
 			return false;
 
-		if (!of_property_read_bool(np, "assigned-clock-parents"))
+		if (!of_property_present(np, "assigned-clock-parents"))
 			return false;
 	}
 
@@ -686,9 +686,9 @@ subsys_initcall(dmtimer_percpu_timer_startup);
 
 static int __init dmtimer_percpu_quirk_init(struct device_node *np, u32 pa)
 {
-	struct device_node *arm_timer;
+	struct device_node *arm_timer __free(device_node) =
+		of_find_compatible_node(NULL, NULL, "arm,armv7-timer");
 
-	arm_timer = of_find_compatible_node(NULL, NULL, "arm,armv7-timer");
 	if (of_device_is_available(arm_timer)) {
 		pr_warn_once("ARM architected timer wrap issue i940 detected\n");
 		return 0;
diff --git a/drivers/clocksource/timer-ti-dm.c b/drivers/clocksource/timer-ti-dm.c
index b7a34b1a975e..3666d94cc8dd 100644
--- a/drivers/clocksource/timer-ti-dm.c
+++ b/drivers/clocksource/timer-ti-dm.c
@@ -1104,8 +1104,12 @@ static int omap_dm_timer_probe(struct platform_device *pdev)
 		return  -ENOMEM;
 
 	timer->irq = platform_get_irq(pdev, 0);
-	if (timer->irq < 0)
-		return timer->irq;
+	if (timer->irq < 0) {
+		if (of_property_read_bool(dev->of_node, "ti,timer-pwm"))
+			dev_info(dev, "Did not find timer interrupt, timer usable in PWM mode only\n");
+		else
+			return timer->irq;
+	}
 
 	timer->io_base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(timer->io_base))
diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 519e096c607c..8f62cfa23fb7 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -273,11 +273,6 @@ i915_request_active_engine(struct i915_request *rq,
 	return ret;
 }
 
-static void __rq_init_watchdog(struct i915_request *rq)
-{
-	rq->watchdog.timer.function = NULL;
-}
-
 static enum hrtimer_restart __rq_watchdog_expired(struct hrtimer *hrtimer)
 {
 	struct i915_request *rq =
@@ -294,6 +289,14 @@ static enum hrtimer_restart __rq_watchdog_expired(struct hrtimer *hrtimer)
 	return HRTIMER_NORESTART;
 }
 
+static void __rq_init_watchdog(struct i915_request *rq)
+{
+	struct i915_request_watchdog *wdg = &rq->watchdog;
+
+	hrtimer_init(&wdg->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	wdg->timer.function = __rq_watchdog_expired;
+}
+
 static void __rq_arm_watchdog(struct i915_request *rq)
 {
 	struct i915_request_watchdog *wdg = &rq->watchdog;
@@ -304,8 +307,6 @@ static void __rq_arm_watchdog(struct i915_request *rq)
 
 	i915_request_get(rq);
 
-	hrtimer_init(&wdg->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	wdg->timer.function = __rq_watchdog_expired;
 	hrtimer_start_range_ns(&wdg->timer,
 			       ns_to_ktime(ce->watchdog.timeout_us *
 					   NSEC_PER_USEC),
@@ -317,7 +318,7 @@ static void __rq_cancel_watchdog(struct i915_request *rq)
 {
 	struct i915_request_watchdog *wdg = &rq->watchdog;
 
-	if (wdg->timer.function && hrtimer_try_to_cancel(&wdg->timer) > 0)
+	if (hrtimer_try_to_cancel(&wdg->timer) > 0)
 		i915_request_put(rq);
 }
 
diff --git a/drivers/media/usb/dvb-usb-v2/anysee.c b/drivers/media/usb/dvb-usb-v2/anysee.c
index 8699846eb416..bea12cdc85e8 100644
--- a/drivers/media/usb/dvb-usb-v2/anysee.c
+++ b/drivers/media/usb/dvb-usb-v2/anysee.c
@@ -46,24 +46,15 @@ static int anysee_ctrl_msg(struct dvb_usb_device *d,
 
 	dev_dbg(&d->udev->dev, "%s: >>> %*ph\n", __func__, slen, state->buf);
 
-	/* We need receive one message more after dvb_usb_generic_rw due
-	   to weird transaction flow, which is 1 x send + 2 x receive. */
+	/*
+	 * We need receive one message more after dvb_usbv2_generic_rw_locked()
+	 * due to weird transaction flow, which is 1 x send + 2 x receive.
+	 */
 	ret = dvb_usbv2_generic_rw_locked(d, state->buf, sizeof(state->buf),
 			state->buf, sizeof(state->buf));
 	if (ret)
 		goto error_unlock;
 
-	/* TODO FIXME: dvb_usb_generic_rw() fails rarely with error code -32
-	 * (EPIPE, Broken pipe). Function supports currently msleep() as a
-	 * parameter but I would not like to use it, since according to
-	 * Documentation/timers/timers-howto.rst it should not be used such
-	 * short, under < 20ms, sleeps. Repeating failed message would be
-	 * better choice as not to add unwanted delays...
-	 * Fixing that correctly is one of those or both;
-	 * 1) use repeat if possible
-	 * 2) add suitable delay
-	 */
-
 	/* get answer, retry few times if error returned */
 	for (i = 0; i < 3; i++) {
 		/* receive 2nd answer */
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
index 8fd22c69855f..a6d50149e0c3 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
@@ -823,8 +823,6 @@ int rt2x00usb_probe(struct usb_interface *usb_intf,
 
 	INIT_WORK(&rt2x00dev->rxdone_work, rt2x00usb_work_rxdone);
 	INIT_WORK(&rt2x00dev->txdone_work, rt2x00usb_work_txdone);
-	hrtimer_init(&rt2x00dev->txstatus_timer, CLOCK_MONOTONIC,
-		     HRTIMER_MODE_REL);
 
 	retval = rt2x00usb_alloc_reg(rt2x00dev);
 	if (retval)
diff --git a/drivers/power/supply/charger-manager.c b/drivers/power/supply/charger-manager.c
index 96f0a7fbf105..09ec0ecf1486 100644
--- a/drivers/power/supply/charger-manager.c
+++ b/drivers/power/supply/charger-manager.c
@@ -1412,10 +1412,9 @@ static inline struct charger_desc *cm_get_drv_data(struct platform_device *pdev)
 	return dev_get_platdata(&pdev->dev);
 }
 
-static enum alarmtimer_restart cm_timer_func(struct alarm *alarm, ktime_t now)
+static void cm_timer_func(struct alarm *alarm, ktime_t now)
 {
 	cm_timer_set = false;
-	return ALARMTIMER_NORESTART;
 }
 
 static int charger_manager_probe(struct platform_device *pdev)