serial: 8250: Decouple RSA probe

Prepare for 8250 split; separate RSA probe and resource management
from base port operations. Override base port operations for the
config_port(), request_port() and release_port() methods to
implement the optional RSA probe and resource management only in
the universal/legacy 8250 driver.

Introduce 'probe' flags for 8250 ports, which allows drivers higher
up the driver stack to enable optional probes.

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

diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 23dc9f9b98398281befa13c6308d61690336d801..c43f74c53cd98259056400cc86b9ff355c4993ca 100644 (file)
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -84,9 +84,6 @@ struct serial8250_config {
 #define UART_BUG_THRE  (1 << 3)        /* UART has buggy THRE reassertion */
 #define UART_BUG_PARITY        (1 << 4)        /* UART mishandles parity if FIFO enabled */
 
-#define PROBE_RSA      (1 << 0)
-#define PROBE_ANY      (~0)
-
 #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
 
 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 257e373bfccdf9f8fca9e7463409a8910005031b..a4ed84a4f8db5c61be9a17be0b702bf657de582b 100644 (file)
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1105,7 +1105,7 @@ static void autoconfig_16550a(struct uart_8250_port *up)
  * whether or not this UART is a 16550A or not, since this will
  * determine whether or not we can use its FIFO features or not.
  */
-static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
+static void autoconfig(struct uart_8250_port *up)
 {
        unsigned char status1, scratch, scratch2, scratch3;
        unsigned char save_lcr, save_mcr;
@@ -1228,7 +1228,7 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
        /*
         * Only probe for RSA ports if we got the region.
         */
-       if (port->type == PORT_16550A && probeflags & PROBE_RSA &&
+       if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA &&
            __enable_rsa(up))
                port->type = PORT_RSA;
 #endif
@@ -2832,10 +2832,6 @@ static void serial8250_release_port(struct uart_port *port)
        struct uart_8250_port *up = up_to_u8250p(port);
 
        serial8250_release_std_resource(up);
-#ifdef CONFIG_SERIAL_8250_RSA
-       if (port->type == PORT_RSA)
-               serial8250_release_rsa_resource(up);
-#endif
 }
 
 static int serial8250_request_port(struct uart_port *port)
@@ -2847,13 +2843,6 @@ static int serial8250_request_port(struct uart_port *port)
                return -ENODEV;
 
        ret = serial8250_request_std_resource(up);
-#ifdef CONFIG_SERIAL_8250_RSA
-       if (ret == 0 && port->type == PORT_RSA) {
-               ret = serial8250_request_rsa_resource(up);
-               if (ret < 0)
-                       serial8250_release_std_resource(up);
-       }
-#endif
 
        return ret;
 }
@@ -3001,7 +2990,6 @@ static void register_dev_spec_attr_grp(struct uart_8250_port *up)
 static void serial8250_config_port(struct uart_port *port, int flags)
 {
        struct uart_8250_port *up = up_to_u8250p(port);
-       int probeflags = 0;
        int ret;
 
        if (port->type == PORT_8250_CIR)
@@ -3015,28 +3003,11 @@ static void serial8250_config_port(struct uart_port *port, int flags)
        if (ret < 0)
                return;
 
-#ifdef CONFIG_SERIAL_8250_RSA
-       if (port->type == PORT_RSA) {
-               if (serial8250_request_rsa_resource(up) == 0)
-                       probeflags |= PROBE_RSA;
-       } else if (flags & UART_CONFIG_TYPE) {
-               int i;
-
-               for (i = 0 ; i < probe_rsa_count; ++i) {
-                       if (probe_rsa[i] == port->iobase) {
-                               if (serial8250_request_rsa_resource(up) == 0)
-                                       probeflags |= PROBE_RSA;
-                               break;
-                       }
-               }
-       }
-#endif
-
        if (port->iotype != up->cur_iotype)
                set_io_from_upio(port);
 
        if (flags & UART_CONFIG_TYPE)
-               autoconfig(up, probeflags);
+               autoconfig(up);
 
        /* if access method is AU, it is a 16550 with a quirk */
        if (port->type == PORT_16550A && port->iotype == UPIO_AU)
@@ -3049,10 +3020,6 @@ static void serial8250_config_port(struct uart_port *port, int flags)
        if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ)
                autoconfig_irq(up);
 
-#ifdef CONFIG_SERIAL_8250_RSA
-       if (port->type != PORT_RSA && probeflags & PROBE_RSA)
-               serial8250_release_rsa_resource(up);
-#endif
        if (port->type == PORT_UNKNOWN)
                serial8250_release_std_resource(up);
 
@@ -3113,6 +3080,9 @@ static struct uart_ops serial8250_pops = {
 #endif
 };
 
+static const struct uart_ops *base_ops;
+static struct uart_ops univ8250_port_ops;
+
 static const struct uart_8250_ops univ8250_driver_ops = {
        .setup_irq      = univ8250_setup_irq,
        .release_irq    = univ8250_release_irq,
@@ -3184,6 +3154,69 @@ static void serial8250_set_defaults(struct uart_8250_port *up)
        }
 }
 
+#ifdef CONFIG_SERIAL_8250_RSA
+
+static void univ8250_config_port(struct uart_port *port, int flags)
+{
+       struct uart_8250_port *up = up_to_u8250p(port);
+
+       up->probe &= ~UART_PROBE_RSA;
+       if (port->type == PORT_RSA) {
+               if (serial8250_request_rsa_resource(up) == 0)
+                       up->probe |= UART_PROBE_RSA;
+       } else if (flags & UART_CONFIG_TYPE) {
+               int i;
+
+               for (i = 0; i < probe_rsa_count; i++) {
+                       if (probe_rsa[i] == up->port.iobase) {
+                               if (serial8250_request_rsa_resource(up) == 0)
+                                       up->probe |= UART_PROBE_RSA;
+                               break;
+                       }
+               }
+       }
+
+       base_ops->config_port(port, flags);
+
+       if (port->type != PORT_RSA && up->probe & UART_PROBE_RSA)
+               serial8250_release_rsa_resource(up);
+}
+
+static int univ8250_request_port(struct uart_port *port)
+{
+       struct uart_8250_port *up = up_to_u8250p(port);
+       int ret;
+
+       ret = base_ops->request_port(port);
+       if (ret == 0 && port->type == PORT_RSA) {
+               ret = serial8250_request_rsa_resource(up);
+               if (ret < 0)
+                       base_ops->release_port(port);
+       }
+
+       return ret;
+}
+
+static void univ8250_release_port(struct uart_port *port)
+{
+       struct uart_8250_port *up = up_to_u8250p(port);
+
+       if (port->type == PORT_RSA)
+               serial8250_release_rsa_resource(up);
+       base_ops->release_port(port);
+}
+
+static void univ8250_rsa_support(struct uart_ops *ops)
+{
+       ops->config_port  = univ8250_config_port;
+       ops->request_port = univ8250_request_port;
+       ops->release_port = univ8250_release_port;
+}
+
+#else
+#define univ8250_rsa_support(x)                do { } while (0)
+#endif /* CONFIG_SERIAL_8250_RSA */
+
 static void __init serial8250_isa_init_ports(void)
 {
        struct uart_8250_port *up;
@@ -3203,6 +3236,9 @@ static void __init serial8250_isa_init_ports(void)
 
                port->line = i;
                serial8250_init_port(up);
+               if (!base_ops)
+                       base_ops = port->ops;
+               port->ops = &univ8250_port_ops;
 
                init_timer(&up->timer);
                up->timer.function = serial8250_timeout;
@@ -3216,6 +3252,10 @@ static void __init serial8250_isa_init_ports(void)
                up->mcr_force = ALPHA_KLUDGE_MCR;
        }
 
+       /* chain base port ops to support Remote Supervisor Adapter */
+       univ8250_port_ops = *base_ops;
+       univ8250_rsa_support(&univ8250_port_ops);
+
        if (share_irqs)
                irqflag = IRQF_SHARED;
 

diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 50735a9ad598d9b10c92243069d49e056f281fcb..78097e7a330a1984942796a4ecf9a156b93f5427 100644 (file)
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -102,6 +102,8 @@ struct uart_8250_port {
        unsigned char           canary;         /* non-zero during system sleep
                                                 *   if no_console_suspend
                                                 */
+       unsigned char           probe;
+#define UART_PROBE_RSA (1 << 0)
 
        /*
         * Some bits in registers are cleared on a read, so they must