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authorIngo Molnar <mingo@kernel.org>2020-02-24 13:36:09 +0300
committerIngo Molnar <mingo@kernel.org>2020-02-24 13:36:09 +0300
commit546121b65f47384e11ec1fa2e55449fc9f4846b2 (patch)
tree8f18470ec7c0c77b0f48eb1b2338e591b0b0aaff /drivers/tty/serial/serial_core.c
parent000619680c3714020ce9db17eef6a4a7ce2dc28b (diff)
parentf8788d86ab28f61f7b46eb6be375f8a726783636 (diff)
downloadlinux-546121b65f47384e11ec1fa2e55449fc9f4846b2.tar.xz
Merge tag 'v5.6-rc3' into sched/core, to pick up fixes and dependent patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/tty/serial/serial_core.c')
-rw-r--r--drivers/tty/serial/serial_core.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 7c2782785736..76e506ee335c 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2603,6 +2603,7 @@ struct tty_driver *uart_console_device(struct console *co, int *index)
*index = co->index;
return p->tty_driver;
}
+EXPORT_SYMBOL_GPL(uart_console_device);
static ssize_t uart_get_attr_uartclk(struct device *dev,
struct device_attribute *attr, char *buf)
@@ -3081,6 +3082,89 @@ void uart_insert_char(struct uart_port *port, unsigned int status,
}
EXPORT_SYMBOL_GPL(uart_insert_char);
+int uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
+{
+ if (!IS_ENABLED(CONFIG_MAGIC_SYSRQ_SERIAL))
+ return 0;
+
+ if (!port->has_sysrq || !port->sysrq)
+ return 0;
+
+ if (ch && time_before(jiffies, port->sysrq)) {
+ handle_sysrq(ch);
+ port->sysrq = 0;
+ return 1;
+ }
+ port->sysrq = 0;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(uart_handle_sysrq_char);
+
+int uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch)
+{
+ if (!IS_ENABLED(CONFIG_MAGIC_SYSRQ_SERIAL))
+ return 0;
+
+ if (!port->has_sysrq || !port->sysrq)
+ return 0;
+
+ if (ch && time_before(jiffies, port->sysrq)) {
+ port->sysrq_ch = ch;
+ port->sysrq = 0;
+ return 1;
+ }
+ port->sysrq = 0;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(uart_prepare_sysrq_char);
+
+void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)
+{
+ int sysrq_ch;
+
+ if (!port->has_sysrq) {
+ spin_unlock_irqrestore(&port->lock, irqflags);
+ return;
+ }
+
+ sysrq_ch = port->sysrq_ch;
+ port->sysrq_ch = 0;
+
+ spin_unlock_irqrestore(&port->lock, irqflags);
+
+ if (sysrq_ch)
+ handle_sysrq(sysrq_ch);
+}
+EXPORT_SYMBOL_GPL(uart_unlock_and_check_sysrq);
+
+/*
+ * We do the SysRQ and SAK checking like this...
+ */
+int uart_handle_break(struct uart_port *port)
+{
+ struct uart_state *state = port->state;
+
+ if (port->handle_break)
+ port->handle_break(port);
+
+ if (port->has_sysrq) {
+ if (port->cons && port->cons->index == port->line) {
+ if (!port->sysrq) {
+ port->sysrq = jiffies + HZ*5;
+ return 1;
+ }
+ port->sysrq = 0;
+ }
+ }
+
+ if (port->flags & UPF_SAK)
+ do_SAK(state->port.tty);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(uart_handle_break);
+
EXPORT_SYMBOL(uart_write_wakeup);
EXPORT_SYMBOL(uart_register_driver);
EXPORT_SYMBOL(uart_unregister_driver);