[PATCH v2] pch_uart: Don't oops if dmi_get_system_info returns NULL

[Alexander Stein <alexander.stein@systec-electronic.com>]

This oops was observed on an Atom based board which has no BIOS, but
a bootloder which doesn't privde DMI data.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
---
Changesin v2:
* Adjust summary
* Describe when dmi_get_system_info could return NULL

If this is ok, i will send an updated patch for the pch_phub too.

 drivers/tty/serial/pch_uart.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f2cb750..4652109 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -1397,6 +1397,7 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
 	int fifosize, base_baud;
 	int port_type;
 	struct pch_uart_driver_data *board;
+	const char *board_name;
 
 	board = &drv_dat[id->driver_data];
 	port_type = board->port_type;
@@ -1412,7 +1413,8 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
 	base_baud = 1843200; /* 1.8432MHz */
 
 	/* quirk for CM-iTC board */
-	if (strstr(dmi_get_system_info(DMI_BOARD_NAME), "CM-iTC"))
+	board_name = dmi_get_system_info(DMI_BOARD_NAME);
+	if (board_name && strstr(board_name, "CM-iTC"))
 		base_baud = 192000000; /* 192.0MHz */
 
 	switch (port_type) {
-- 
1.7.3.4