@@ -110,6 +110,8 @@ static inline void serial_dl_write(struct uart_8250_port *up, int value)
up->dl_write(up, value);
}
+struct uart_8250_port *serial8250_get_port(int line);
+
#if defined(__alpha__) && !defined(CONFIG_PCI)
/*
* Digital did something really horribly wrong with the OUT1 and OUT2
@@ -2755,6 +2755,23 @@ static struct uart_ops serial8250_pops = {
static struct uart_8250_port serial8250_ports[UART_NR];
+/**
+ * serial8250_get_port - retrieve struct uart_8250_port
+ * @line: serial line number
+ *
+ * This function retrieves struct uart_8250_port for the specific line.
+ * This struct *must* *not* be used to perform a 8250 or serial core operation
+ * which is not accessible otherwise. Its only purpose is to make the struct
+ * accessible to the runtime-pm callbacks for context suspend/restore.
+ * The lock assumption made here is none because runtime-pm suspend/resume
+ * callbacks should not be invoked there is any operation performed on the port.
+ */
+struct uart_8250_port *serial8250_get_port(int line)
+{
+ return &serial8250_ports[line];
+}
+EXPORT_SYMBOL_GPL(serial8250_get_port);
+
static void (*serial8250_isa_config)(int port, struct uart_port *up,
unsigned short *capabilities);
There is no access to access a struct uart_8250_port for a specific line. This is only required outside of the 8250/uart callbacks like for devices' suspend & remove callbacks. For those the 8250-core provides wrapper like serial8250_unregister_port() which passes the struct to the proper function based on the line argument. For runtime suspend I need access to this struct not only to make serial_out() work but also to properly restore up->ier and up->mcr. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- drivers/tty/serial/8250/8250.h | 2 ++ drivers/tty/serial/8250/8250_core.c | 17 +++++++++++++++++ 2 files changed, 19 insertions(+)