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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /arch/x86/boot/tty.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'arch/x86/boot/tty.c')
-rw-r--r--arch/x86/boot/tty.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/x86/boot/tty.c b/arch/x86/boot/tty.c
new file mode 100644
index 000000000..f7eb976b0
--- /dev/null
+++ b/arch/x86/boot/tty.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright 2007 rPath, Inc. - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * Very simple screen and serial I/O
+ */
+
+#include "boot.h"
+
+int early_serial_base;
+
+#define XMTRDY 0x20
+
+#define TXR 0 /* Transmit register (WRITE) */
+#define LSR 5 /* Line Status */
+
+/*
+ * These functions are in .inittext so they can be used to signal
+ * error during initialization.
+ */
+
+static void __section(".inittext") serial_putchar(int ch)
+{
+ unsigned timeout = 0xffff;
+
+ while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+ cpu_relax();
+
+ outb(ch, early_serial_base + TXR);
+}
+
+static void __section(".inittext") bios_putchar(int ch)
+{
+ struct biosregs ireg;
+
+ initregs(&ireg);
+ ireg.bx = 0x0007;
+ ireg.cx = 0x0001;
+ ireg.ah = 0x0e;
+ ireg.al = ch;
+ intcall(0x10, &ireg, NULL);
+}
+
+void __section(".inittext") putchar(int ch)
+{
+ if (ch == '\n')
+ putchar('\r'); /* \n -> \r\n */
+
+ bios_putchar(ch);
+
+ if (early_serial_base != 0)
+ serial_putchar(ch);
+}
+
+void __section(".inittext") puts(const char *str)
+{
+ while (*str)
+ putchar(*str++);
+}
+
+/*
+ * Read the CMOS clock through the BIOS, and return the
+ * seconds in BCD.
+ */
+
+static u8 gettime(void)
+{
+ struct biosregs ireg, oreg;
+
+ initregs(&ireg);
+ ireg.ah = 0x02;
+ intcall(0x1a, &ireg, &oreg);
+
+ return oreg.dh;
+}
+
+/*
+ * Read from the keyboard
+ */
+int getchar(void)
+{
+ struct biosregs ireg, oreg;
+
+ initregs(&ireg);
+ /* ireg.ah = 0x00; */
+ intcall(0x16, &ireg, &oreg);
+
+ return oreg.al;
+}
+
+static int kbd_pending(void)
+{
+ struct biosregs ireg, oreg;
+
+ initregs(&ireg);
+ ireg.ah = 0x01;
+ intcall(0x16, &ireg, &oreg);
+
+ return !(oreg.eflags & X86_EFLAGS_ZF);
+}
+
+void kbd_flush(void)
+{
+ for (;;) {
+ if (!kbd_pending())
+ break;
+ getchar();
+ }
+}
+
+int getchar_timeout(void)
+{
+ int cnt = 30;
+ int t0, t1;
+
+ t0 = gettime();
+
+ while (cnt) {
+ if (kbd_pending())
+ return getchar();
+
+ t1 = gettime();
+ if (t0 != t1) {
+ cnt--;
+ t0 = t1;
+ }
+ }
+
+ return 0; /* Timeout! */
+}
+