From 506ada89629ec7059b96ecfb0dc7d33ece0103ca Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 17:05:56 -0700 Subject: bpf: mark a NULL kfunc argument precise check_kfunc_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value. Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com Signed-off-by: Alexei Starovoitov --- drivers/leds/leds-expresswire.c | 82 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 drivers/leds/leds-expresswire.c (limited to 'drivers/leds/leds-expresswire.c') 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 +#include +#include +#include +#include +#include + +#include + +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"); -- cgit v1.3.1