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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/s390/char/ctrlchar.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'drivers/s390/char/ctrlchar.c')
-rw-r--r--drivers/s390/char/ctrlchar.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/s390/char/ctrlchar.c b/drivers/s390/char/ctrlchar.c
new file mode 100644
index 000000000..6f2b64040
--- /dev/null
+++ b/drivers/s390/char/ctrlchar.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Unified handling of special chars.
+ *
+ * Copyright IBM Corp. 2001
+ * Author(s): Fritz Elfert <felfert@millenux.com> <elfert@de.ibm.com>
+ *
+ */
+
+#include <linux/stddef.h>
+#include <asm/errno.h>
+#include <linux/sysrq.h>
+#include <linux/ctype.h>
+
+#include "ctrlchar.h"
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static struct sysrq_work ctrlchar_sysrq;
+
+static void
+ctrlchar_handle_sysrq(struct work_struct *work)
+{
+ struct sysrq_work *sysrq = container_of(work, struct sysrq_work, work);
+
+ handle_sysrq(sysrq->key);
+}
+
+void schedule_sysrq_work(struct sysrq_work *sw)
+{
+ INIT_WORK(&sw->work, ctrlchar_handle_sysrq);
+ schedule_work(&sw->work);
+}
+#endif
+
+
+/**
+ * ctrlchar_handle - check for special chars at start of input
+ *
+ * @buf: console input buffer
+ * @len: length of valid data in buffer
+ * @tty: the tty struct for this console
+ *
+ * Return: CTRLCHAR_NONE, if nothing matched,
+ * CTRLCHAR_SYSRQ, if sysrq was encountered
+ * otherwise char to be inserted logically or'ed
+ * with CTRLCHAR_CTRL
+ */
+unsigned int
+ctrlchar_handle(const unsigned char *buf, int len, struct tty_struct *tty)
+{
+ if ((len < 2) || (len > 3))
+ return CTRLCHAR_NONE;
+
+ /* hat is 0xb1 in codepage 037 (US etc.) and thus */
+ /* converted to 0x5e in ascii ('^') */
+ if ((buf[0] != '^') && (buf[0] != '\252'))
+ return CTRLCHAR_NONE;
+
+#ifdef CONFIG_MAGIC_SYSRQ
+ /* racy */
+ if (len == 3 && buf[1] == '-') {
+ ctrlchar_sysrq.key = buf[2];
+ schedule_sysrq_work(&ctrlchar_sysrq);
+ return CTRLCHAR_SYSRQ;
+ }
+#endif
+
+ if (len != 2)
+ return CTRLCHAR_NONE;
+
+ switch (tolower(buf[1])) {
+ case 'c':
+ return INTR_CHAR(tty) | CTRLCHAR_CTRL;
+ case 'd':
+ return EOF_CHAR(tty) | CTRLCHAR_CTRL;
+ case 'z':
+ return SUSP_CHAR(tty) | CTRLCHAR_CTRL;
+ }
+ return CTRLCHAR_NONE;
+}