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authorRob Herring (Arm) <robh@kernel.org>2026-08-31 14:43:51 -0500
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2026-09-13 18:17:31 -0700
commit55fc280e951ab2b39f3dcb640edc1b1eebc6d173 (patch)
treef0b5f37b42fc13b9908a31b657c646b024231cdd /drivers/clocksource/mmio.c
downloadlinux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.tar.gz
linux-stable-55fc280e951ab2b39f3dcb640edc1b1eebc6d173.zip
Input: tsc2007 - read "ti,poll-period" as u32grafted
The "ti,poll-period" property is documented as a normal uint32 cell. The driver used a u64 helper, which makes the helper type disagree with the schema even though the stored value is still small. Read "ti,poll-period" with the u32 helper matching the documented DT cell size. Assisted-by: Codex:gpt-5-5 Signed-off-by: Rob Herring (Arm) <robh@kernel.org> Link: https://patch.msgid.link/20260831194352.1185860-1-robh@kernel.org Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/clocksource/mmio.c')
-rw-r--r--drivers/clocksource/mmio.c75
1 files changed, 75 insertions, 0 deletions
diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c
new file mode 100644
index 000000000..0fee8edb8
--- /dev/null
+++ b/drivers/clocksource/mmio.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Generic MMIO clocksource support
+ */
+#include <linux/clocksource.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+
+struct clocksource_mmio {
+ void __iomem *reg;
+ struct clocksource clksrc;
+};
+
+static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c)
+{
+ return container_of(c, struct clocksource_mmio, clksrc);
+}
+
+u64 clocksource_mmio_readl_up(struct clocksource *c)
+{
+ return (u64)readl_relaxed(to_mmio_clksrc(c)->reg);
+}
+EXPORT_SYMBOL_GPL(clocksource_mmio_readl_up);
+
+u64 clocksource_mmio_readl_down(struct clocksource *c)
+{
+ return ~(u64)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
+}
+EXPORT_SYMBOL_GPL(clocksource_mmio_readl_down);
+
+u64 clocksource_mmio_readw_up(struct clocksource *c)
+{
+ return (u64)readw_relaxed(to_mmio_clksrc(c)->reg);
+}
+EXPORT_SYMBOL_GPL(clocksource_mmio_readw_up);
+
+u64 clocksource_mmio_readw_down(struct clocksource *c)
+{
+ return ~(u64)readw_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
+}
+EXPORT_SYMBOL_GPL(clocksource_mmio_readw_down);
+
+/**
+ * clocksource_mmio_init - Initialize a simple mmio based clocksource
+ * @base: Virtual address of the clock readout register
+ * @name: Name of the clocksource
+ * @hz: Frequency of the clocksource in Hz
+ * @rating: Rating of the clocksource
+ * @bits: Number of valid bits
+ * @read: One of clocksource_mmio_read*() above
+ */
+int clocksource_mmio_init(void __iomem *base, const char *name,
+ unsigned long hz, int rating, unsigned bits,
+ u64 (*read)(struct clocksource *))
+{
+ struct clocksource_mmio *cs;
+
+ if (bits > 64 || bits < 16)
+ return -EINVAL;
+
+ cs = kzalloc_obj(struct clocksource_mmio);
+ if (!cs)
+ return -ENOMEM;
+
+ cs->reg = base;
+ cs->clksrc.name = name;
+ cs->clksrc.rating = rating;
+ cs->clksrc.read = read;
+ cs->clksrc.mask = CLOCKSOURCE_MASK(bits);
+ cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+ return clocksource_register_hz(&cs->clksrc, hz);
+}
+EXPORT_SYMBOL_GPL(clocksource_mmio_init);