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authorSalah Triki <salah.triki@gmail.com>2026-09-17 14:00:52 +0100
committerJonathan Cameron <jonathan.cameron@oss.qualcomm.com>2026-09-30 18:59:55 +0100
commite8dd273d199f5bbe295a8e3d8b777c5505b6b2e1 (patch)
tree767c7e109d3e6b9ec6549e99dfec9085d01318ad /drivers/clocksource/bcm2835_timer.c
downloadlinux-stable-e8dd273d199f5bbe295a8e3d8b777c5505b6b2e1.tar.gz
linux-stable-e8dd273d199f5bbe295a8e3d8b777c5505b6b2e1.zip
iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted
isl29501_register_write() was returning a u32 instead of an int. Since the function returns negative error codes (such as -ERANGE or return values from i2c_smbus_write_byte_data()), returning an unsigned integer type prevents callers from correctly checking for negative error conditions. Fix this by changing the function return type from u32 to int. This was found through manual code review. Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.") Signed-off-by: Salah Triki <salah.triki@gmail.com> Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Diffstat (limited to 'drivers/clocksource/bcm2835_timer.c')
-rw-r--r--drivers/clocksource/bcm2835_timer.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/clocksource/bcm2835_timer.c b/drivers/clocksource/bcm2835_timer.c
new file mode 100644
index 000000000..d7662301b
--- /dev/null
+++ b/drivers/clocksource/bcm2835_timer.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2012 Simon Arlott
+ */
+
+#include <linux/bitops.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sched_clock.h>
+
+#include <asm/irq.h>
+
+#define REG_CONTROL 0x00
+#define REG_COUNTER_LO 0x04
+#define REG_COUNTER_HI 0x08
+#define REG_COMPARE(n) (0x0c + (n) * 4)
+#define MAX_TIMER 3
+#define DEFAULT_TIMER 3
+
+struct bcm2835_timer {
+ void __iomem *control;
+ void __iomem *compare;
+ int match_mask;
+ struct clock_event_device evt;
+};
+
+static void __iomem *system_clock __read_mostly;
+
+static u64 notrace bcm2835_sched_read(void)
+{
+ return readl_relaxed(system_clock);
+}
+
+static int bcm2835_time_set_next_event(unsigned long event,
+ struct clock_event_device *evt_dev)
+{
+ struct bcm2835_timer *timer = container_of(evt_dev,
+ struct bcm2835_timer, evt);
+ writel_relaxed(readl_relaxed(system_clock) + event,
+ timer->compare);
+ return 0;
+}
+
+static irqreturn_t bcm2835_time_interrupt(int irq, void *dev_id)
+{
+ struct bcm2835_timer *timer = dev_id;
+ void (*event_handler)(struct clock_event_device *);
+ if (readl_relaxed(timer->control) & timer->match_mask) {
+ writel_relaxed(timer->match_mask, timer->control);
+
+ event_handler = READ_ONCE(timer->evt.event_handler);
+ if (event_handler)
+ event_handler(&timer->evt);
+ return IRQ_HANDLED;
+ } else {
+ return IRQ_NONE;
+ }
+}
+
+static int __init bcm2835_timer_init(struct device_node *node)
+{
+ void __iomem *base;
+ u32 freq;
+ int irq, ret;
+ struct bcm2835_timer *timer;
+
+ base = of_iomap(node, 0);
+ if (!base) {
+ pr_err("Can't remap registers\n");
+ return -ENXIO;
+ }
+
+ ret = of_property_read_u32(node, "clock-frequency", &freq);
+ if (ret) {
+ pr_err("Can't read clock-frequency\n");
+ goto err_iounmap;
+ }
+
+ system_clock = base + REG_COUNTER_LO;
+ sched_clock_register(bcm2835_sched_read, 32, freq);
+
+ clocksource_mmio_init(base + REG_COUNTER_LO, node->name,
+ freq, 300, 32, clocksource_mmio_readl_up);
+
+ irq = irq_of_parse_and_map(node, DEFAULT_TIMER);
+ if (irq <= 0) {
+ pr_err("Can't parse IRQ\n");
+ ret = -EINVAL;
+ goto err_iounmap;
+ }
+
+ timer = kzalloc_obj(*timer);
+ if (!timer) {
+ ret = -ENOMEM;
+ goto err_iounmap;
+ }
+
+ timer->control = base + REG_CONTROL;
+ timer->compare = base + REG_COMPARE(DEFAULT_TIMER);
+ timer->match_mask = BIT(DEFAULT_TIMER);
+ timer->evt.name = node->name;
+ timer->evt.rating = 300;
+ timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
+ timer->evt.set_next_event = bcm2835_time_set_next_event;
+ timer->evt.cpumask = cpumask_of(0);
+
+ ret = request_irq(irq, bcm2835_time_interrupt, IRQF_TIMER | IRQF_SHARED,
+ node->name, timer);
+ if (ret) {
+ pr_err("Can't set up timer IRQ\n");
+ goto err_timer_free;
+ }
+
+ clockevents_config_and_register(&timer->evt, freq, 0xf, 0xffffffff);
+
+ pr_info("bcm2835: system timer (irq = %d)\n", irq);
+
+ return 0;
+
+err_timer_free:
+ kfree(timer);
+
+err_iounmap:
+ iounmap(base);
+ return ret;
+}
+TIMER_OF_DECLARE(bcm2835, "brcm,bcm2835-system-timer",
+ bcm2835_timer_init);