diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 90e2ea1e8afe..1f2b4c12eead 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -22,6 +22,7 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/ktime.h> +#include <linux/mutex.h> #include <linux/pinctrl/consumer.h> #include <linux/rational.h> #include <linux/slab.h> @@ -2079,6 +2080,9 @@ static const struct uart_ops imx_uart_pops = { static struct imx_port *imx_uart_ports[UART_NR]; +/* Held across uart_add/remove_one_port(); console callbacks must not take it. */ +static DEFINE_MUTEX(imx_uart_ports_lock); + #if IS_ENABLED(CONFIG_SERIAL_IMX_CONSOLE) static void imx_uart_console_putchar(struct uart_port *port, unsigned char ch) { @@ -2631,11 +2635,19 @@ static int imx_uart_probe(struct platform_device *pdev) } } - imx_uart_ports[sport->port.line] = sport; - platform_set_drvdata(pdev, sport); - ret = uart_add_one_port(&imx_uart_uart_driver, &sport->port); + scoped_guard(mutex, &imx_uart_ports_lock) { + if (imx_uart_ports[sport->port.line]) { + ret = -EBUSY; + } else { + imx_uart_ports[sport->port.line] = sport; + ret = uart_add_one_port(&imx_uart_uart_driver, + &sport->port); + if (ret) + imx_uart_ports[sport->port.line] = NULL; + } + } err_clk: clk_disable_unprepare(sport->clk_ipg); @@ -2647,7 +2659,9 @@ static void imx_uart_remove(struct platform_device *pdev) { struct imx_port *sport = platform_get_drvdata(pdev); + guard(mutex)(&imx_uart_ports_lock); uart_remove_one_port(&imx_uart_uart_driver, &sport->port); + imx_uart_ports[sport->port.line] = NULL; } static void imx_uart_restore_context(struct imx_port *sport) |