serial: core: Add minor field to uart_port

UART drivers that share ttyS namespace cannot trivially compute the
ttyS index from the port->line value since the minor_start may be
offset from minor 64. Further, to do so requires a pointer to the
uart driver since there is no back pointer from uart_port to
uart_driver.

Rather than have UART drivers computing the minor value by themselves,
encapsulate within the serial core at port registration time.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 8379e3fa01625d14ae69f63053d0da26d53b3276..a373eff44ae8aece13552e20a5f16092ef4ec71b 100644 (file)
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2682,6 +2682,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 
        state->pm_state = UART_PM_STATE_UNDEFINED;
        uport->cons = drv->cons;
+       uport->minor = drv->tty_driver->minor_start + uport->line;
 
        /*
         * If this port is a console, then the spinlock is already

diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index b0148e7bcbfa0ad8bc5686f2ea8d60b5c663f99a..980170e5a982adc7ffd9929d69c82049f87827c0 100644 (file)
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -235,6 +235,7 @@ struct uart_port {
        const struct uart_ops   *ops;
        unsigned int            custom_divisor;
        unsigned int            line;                   /* port index */
+       unsigned int            minor;
        resource_size_t         mapbase;                /* for ioremap */
        struct device           *dev;                   /* parent device */
        unsigned char           hub6;                   /* this should be in the 8250 driver */