kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 105 insertions, 0 deletions

diff --git a/include/sound/da7218.h b/include/sound/da7218.h
new file mode 100644
index 000000000..9d0a82fbe
--- /dev/null
+++ b/include/sound/da7218.h
@@ -0,0 +1,105 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * da7218.h - DA7218 ASoC Codec Driver Platform Data
+ *
+ * Copyright (c) 2015 Dialog Semiconductor
+ *
+ * Author: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
+ */
+
+#ifndef _DA7218_PDATA_H
+#define _DA7218_PDATA_H
+
+/* Mic Bias */
+enum da7218_micbias_voltage {
+	DA7218_MICBIAS_1_2V = -1,
+	DA7218_MICBIAS_1_6V,
+	DA7218_MICBIAS_1_8V,
+	DA7218_MICBIAS_2_0V,
+	DA7218_MICBIAS_2_2V,
+	DA7218_MICBIAS_2_4V,
+	DA7218_MICBIAS_2_6V,
+	DA7218_MICBIAS_2_8V,
+	DA7218_MICBIAS_3_0V,
+};
+
+enum da7218_mic_amp_in_sel {
+	DA7218_MIC_AMP_IN_SEL_DIFF = 0,
+	DA7218_MIC_AMP_IN_SEL_SE_P,
+	DA7218_MIC_AMP_IN_SEL_SE_N,
+};
+
+/* DMIC */
+enum da7218_dmic_data_sel {
+	DA7218_DMIC_DATA_LRISE_RFALL = 0,
+	DA7218_DMIC_DATA_LFALL_RRISE,
+};
+
+enum da7218_dmic_samplephase {
+	DA7218_DMIC_SAMPLE_ON_CLKEDGE = 0,
+	DA7218_DMIC_SAMPLE_BETWEEN_CLKEDGE,
+};
+
+enum da7218_dmic_clk_rate {
+	DA7218_DMIC_CLK_3_0MHZ = 0,
+	DA7218_DMIC_CLK_1_5MHZ,
+};
+
+/* Headphone Detect */
+enum da7218_hpldet_jack_rate {
+	DA7218_HPLDET_JACK_RATE_5US = 0,
+	DA7218_HPLDET_JACK_RATE_10US,
+	DA7218_HPLDET_JACK_RATE_20US,
+	DA7218_HPLDET_JACK_RATE_40US,
+	DA7218_HPLDET_JACK_RATE_80US,
+	DA7218_HPLDET_JACK_RATE_160US,
+	DA7218_HPLDET_JACK_RATE_320US,
+	DA7218_HPLDET_JACK_RATE_640US,
+};
+
+enum da7218_hpldet_jack_debounce {
+	DA7218_HPLDET_JACK_DEBOUNCE_OFF = 0,
+	DA7218_HPLDET_JACK_DEBOUNCE_2,
+	DA7218_HPLDET_JACK_DEBOUNCE_3,
+	DA7218_HPLDET_JACK_DEBOUNCE_4,
+};
+
+enum da7218_hpldet_jack_thr {
+	DA7218_HPLDET_JACK_THR_84PCT = 0,
+	DA7218_HPLDET_JACK_THR_88PCT,
+	DA7218_HPLDET_JACK_THR_92PCT,
+	DA7218_HPLDET_JACK_THR_96PCT,
+};
+
+struct da7218_hpldet_pdata {
+	enum da7218_hpldet_jack_rate jack_rate;
+	enum da7218_hpldet_jack_debounce jack_debounce;
+	enum da7218_hpldet_jack_thr jack_thr;
+	bool comp_inv;
+	bool hyst;
+	bool discharge;
+};
+
+struct da7218_pdata {
+	/* Mic */
+	enum da7218_micbias_voltage micbias1_lvl;
+	enum da7218_micbias_voltage micbias2_lvl;
+	enum da7218_mic_amp_in_sel mic1_amp_in_sel;
+	enum da7218_mic_amp_in_sel mic2_amp_in_sel;
+
+	/* DMIC */
+	enum da7218_dmic_data_sel dmic1_data_sel;
+	enum da7218_dmic_data_sel dmic2_data_sel;
+	enum da7218_dmic_samplephase dmic1_samplephase;
+	enum da7218_dmic_samplephase dmic2_samplephase;
+	enum da7218_dmic_clk_rate dmic1_clk_rate;
+	enum da7218_dmic_clk_rate dmic2_clk_rate;
+
+	/* HP Diff Supply - DA7217 only */
+	bool hp_diff_single_supply;
+
+	/* HP Detect - DA7218 only */
+	struct da7218_hpldet_pdata *hpldet_pdata;
+};
+
+#endif /* _DA7218_PDATA_H */