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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /drivers/tty/ttynull.c
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'drivers/tty/ttynull.c')
-rw-r--r--drivers/tty/ttynull.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/tty/ttynull.c b/drivers/tty/ttynull.c
new file mode 100644
index 000000000..6b2f7208b
--- /dev/null
+++ b/drivers/tty/ttynull.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Axis Communications AB
+ *
+ * Based on ttyprintk.c:
+ * Copyright (C) 2010 Samo Pogacnik
+ */
+
+#include <linux/console.h>
+#include <linux/module.h>
+#include <linux/tty.h>
+
+static const struct tty_port_operations ttynull_port_ops;
+static struct tty_driver *ttynull_driver;
+static struct tty_port ttynull_port;
+
+static int ttynull_open(struct tty_struct *tty, struct file *filp)
+{
+ return tty_port_open(&ttynull_port, tty, filp);
+}
+
+static void ttynull_close(struct tty_struct *tty, struct file *filp)
+{
+ tty_port_close(&ttynull_port, tty, filp);
+}
+
+static void ttynull_hangup(struct tty_struct *tty)
+{
+ tty_port_hangup(&ttynull_port);
+}
+
+static ssize_t ttynull_write(struct tty_struct *tty, const u8 *buf,
+ size_t count)
+{
+ return count;
+}
+
+static unsigned int ttynull_write_room(struct tty_struct *tty)
+{
+ return 65536;
+}
+
+static const struct tty_operations ttynull_ops = {
+ .open = ttynull_open,
+ .close = ttynull_close,
+ .hangup = ttynull_hangup,
+ .write = ttynull_write,
+ .write_room = ttynull_write_room,
+};
+
+static struct tty_driver *ttynull_device(struct console *c, int *index)
+{
+ *index = 0;
+ return ttynull_driver;
+}
+
+static struct console ttynull_console = {
+ .name = "ttynull",
+ .device = ttynull_device,
+};
+
+static int __init ttynull_init(void)
+{
+ struct tty_driver *driver;
+ int ret;
+
+ driver = tty_alloc_driver(1,
+ TTY_DRIVER_RESET_TERMIOS |
+ TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_UNNUMBERED_NODE);
+ if (IS_ERR(driver))
+ return PTR_ERR(driver);
+
+ tty_port_init(&ttynull_port);
+ ttynull_port.ops = &ttynull_port_ops;
+
+ driver->driver_name = "ttynull";
+ driver->name = "ttynull";
+ driver->type = TTY_DRIVER_TYPE_CONSOLE;
+ driver->init_termios = tty_std_termios;
+ driver->init_termios.c_oflag = OPOST | OCRNL | ONOCR | ONLRET;
+ tty_set_operations(driver, &ttynull_ops);
+ tty_port_link_device(&ttynull_port, driver, 0);
+
+ ret = tty_register_driver(driver);
+ if (ret < 0) {
+ tty_driver_kref_put(driver);
+ tty_port_destroy(&ttynull_port);
+ return ret;
+ }
+
+ ttynull_driver = driver;
+ register_console(&ttynull_console);
+
+ return 0;
+}
+
+static void __exit ttynull_exit(void)
+{
+ unregister_console(&ttynull_console);
+ tty_unregister_driver(ttynull_driver);
+ tty_driver_kref_put(ttynull_driver);
+ tty_port_destroy(&ttynull_port);
+}
+
+module_init(ttynull_init);
+module_exit(ttynull_exit);
+
+MODULE_DESCRIPTION("NULL TTY driver");
+MODULE_LICENSE("GPL v2");