serial: samsung: Add poll_get_char & poll_put_char
The following patch allows users to use KGDB over serial console on
board based on Samsung SOC. It has been tested on a board using
exynos5.
[dianders: changed poll to return NO_POLL_CHAR, which appears to
fix 'help' in kgdb; also updated commit message]
Signed-off-by: Julien Pichon <pichon.jln@gmail.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 8eef114..7f04717 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -876,11 +876,24 @@
static struct console s3c24xx_serial_console;
+static int __init s3c24xx_serial_console_init(void)
+{
+ register_console(&s3c24xx_serial_console);
+ return 0;
+}
+console_initcall(s3c24xx_serial_console_init);
+
#define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
#else
#define S3C24XX_SERIAL_CONSOLE NULL
#endif
+#ifdef CONFIG_CONSOLE_POLL
+static int s3c24xx_serial_get_poll_char(struct uart_port *port);
+static void s3c24xx_serial_put_poll_char(struct uart_port *port,
+ unsigned char c);
+#endif
+
static struct uart_ops s3c24xx_serial_ops = {
.pm = s3c24xx_serial_pm,
.tx_empty = s3c24xx_serial_tx_empty,
@@ -899,6 +912,10 @@
.request_port = s3c24xx_serial_request_port,
.config_port = s3c24xx_serial_config_port,
.verify_port = s3c24xx_serial_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = s3c24xx_serial_get_poll_char,
+ .poll_put_char = s3c24xx_serial_put_poll_char,
+#endif
};
static struct uart_driver s3c24xx_uart_drv = {
@@ -1316,6 +1333,36 @@
return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
}
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for writing and reading from the uart while
+ * in an interrupt or debug context.
+ */
+
+static int s3c24xx_serial_get_poll_char(struct uart_port *port)
+{
+ struct s3c24xx_uart_port *ourport = to_ourport(port);
+ unsigned int ufstat;
+
+ ufstat = rd_regl(port, S3C2410_UFSTAT);
+ if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
+ return NO_POLL_CHAR;
+
+ return rd_regb(port, S3C2410_URXH);
+}
+
+static void s3c24xx_serial_put_poll_char(struct uart_port *port,
+ unsigned char c)
+{
+ unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
+
+ while (!s3c24xx_serial_console_txrdy(port, ufcon))
+ cpu_relax();
+ wr_regb(cons_uart, S3C2410_UTXH, c);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
static void
s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
{