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authorDaniel Vetter <daniel.vetter@ffwll.ch>2017-07-26 14:23:10 +0300
committerDaniel Vetter <daniel.vetter@ffwll.ch>2017-07-26 14:43:33 +0300
commitaf055598542670c8533a58582813b1419949cae0 (patch)
tree901fa1bf635d5c1e91d08f9f4c2e4943516dbb71 /drivers/tty/n_null.c
parent9f15a4ab19ab33658dbc9fd37be5210e8c1ac622 (diff)
parent2d62c799f8ffac4f7ffba6a4e7f148827dfc24c7 (diff)
downloadlinux-af055598542670c8533a58582813b1419949cae0.tar.xz
Merge airlied/drm-next into drm-misc-next
I need this to be able to apply the deferred fbdev setup patches, I need the relevant prep work that landed through the drm-intel tree. Also squash in conflict fixup from Laurent Pinchart. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/tty/n_null.c')
-rw-r--r--drivers/tty/n_null.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/tty/n_null.c b/drivers/tty/n_null.c
new file mode 100644
index 000000000000..d63261c36e42
--- /dev/null
+++ b/drivers/tty/n_null.c
@@ -0,0 +1,80 @@
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/module.h>
+
+/*
+ * n_null.c - Null line discipline used in the failure path
+ *
+ * Copyright (C) Intel 2017
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+static int n_null_open(struct tty_struct *tty)
+{
+ return 0;
+}
+
+static void n_null_close(struct tty_struct *tty)
+{
+}
+
+static ssize_t n_null_read(struct tty_struct *tty, struct file *file,
+ unsigned char __user * buf, size_t nr)
+{
+ return -EOPNOTSUPP;
+}
+
+static ssize_t n_null_write(struct tty_struct *tty, struct file *file,
+ const unsigned char *buf, size_t nr)
+{
+ return -EOPNOTSUPP;
+}
+
+static void n_null_receivebuf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp,
+ int cnt)
+{
+}
+
+static struct tty_ldisc_ops null_ldisc = {
+ .owner = THIS_MODULE,
+ .magic = TTY_LDISC_MAGIC,
+ .name = "n_null",
+ .open = n_null_open,
+ .close = n_null_close,
+ .read = n_null_read,
+ .write = n_null_write,
+ .receive_buf = n_null_receivebuf
+};
+
+static int __init n_null_init(void)
+{
+ BUG_ON(tty_register_ldisc(N_NULL, &null_ldisc));
+ return 0;
+}
+
+static void __exit n_null_exit(void)
+{
+ tty_unregister_ldisc(N_NULL);
+}
+
+module_init(n_null_init);
+module_exit(n_null_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alan Cox");
+MODULE_ALIAS_LDISC(N_NULL);
+MODULE_DESCRIPTION("Null ldisc driver");