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authorBreno Leitao <leitao@debian.org>2026-08-05 07:52:36 -0700
committerTejun Heo <tj@kernel.org>2026-08-10 11:47:20 -1000
commita5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 (patch)
tree39f5b258386e1127d253d293194e9a2991bf3c34 /drivers/leds/leds-expresswire.c
downloadlinux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.tar.gz
linux-stable-a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656.zip
workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted
apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'drivers/leds/leds-expresswire.c')
-rw-r--r--drivers/leds/leds-expresswire.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/leds/leds-expresswire.c b/drivers/leds/leds-expresswire.c
new file mode 100644
index 000000000..25c6b159a
--- /dev/null
+++ b/drivers/leds/leds-expresswire.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Shared library for Kinetic's ExpressWire protocol.
+ * This protocol works by pulsing the ExpressWire IC's control GPIO.
+ * ktd2692 and ktd2801 are known to use this protocol.
+ */
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/gpio/consumer.h>
+#include <linux/irqflags.h>
+#include <linux/types.h>
+
+#include <linux/leds-expresswire.h>
+
+void expresswire_power_off(struct expresswire_common_props *props)
+{
+ gpiod_set_value_cansleep(props->ctrl_gpio, 0);
+ fsleep(props->timing.poweroff_us);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_power_off, "EXPRESSWIRE");
+
+void expresswire_enable(struct expresswire_common_props *props)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ gpiod_set_value(props->ctrl_gpio, 1);
+ udelay(props->timing.detect_delay_us);
+ gpiod_set_value(props->ctrl_gpio, 0);
+ udelay(props->timing.detect_us);
+ gpiod_set_value(props->ctrl_gpio, 1);
+
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_enable, "EXPRESSWIRE");
+
+static void expresswire_start(struct expresswire_common_props *props)
+{
+ gpiod_set_value(props->ctrl_gpio, 1);
+ udelay(props->timing.data_start_us);
+}
+
+static void expresswire_end(struct expresswire_common_props *props)
+{
+ gpiod_set_value(props->ctrl_gpio, 0);
+ udelay(props->timing.end_of_data_low_us);
+ gpiod_set_value(props->ctrl_gpio, 1);
+ udelay(props->timing.end_of_data_high_us);
+}
+
+static void expresswire_set_bit(struct expresswire_common_props *props, bool bit)
+{
+ if (bit) {
+ gpiod_set_value(props->ctrl_gpio, 0);
+ udelay(props->timing.short_bitset_us);
+ gpiod_set_value(props->ctrl_gpio, 1);
+ udelay(props->timing.long_bitset_us);
+ } else {
+ gpiod_set_value(props->ctrl_gpio, 0);
+ udelay(props->timing.long_bitset_us);
+ gpiod_set_value(props->ctrl_gpio, 1);
+ udelay(props->timing.short_bitset_us);
+ }
+}
+
+void expresswire_write_u8(struct expresswire_common_props *props, u8 val)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ expresswire_start(props);
+ for (int i = 7; i >= 0; i--)
+ expresswire_set_bit(props, val & BIT(i));
+ expresswire_end(props);
+
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_NS_GPL(expresswire_write_u8, "EXPRESSWIRE");