serial: pl011: add console matching function

commit 10879ae5f12e9cab3c4e8e9504c1aaa8a033bde7 upstream.

This patch adds function pl011_console_match() that implements
method match of struct console.  It allows to match consoles against
data specified in a string, for example taken from command line or
compiled by ACPI SPCR table handler.

This patch was merged to tty-next but then reverted because of
conflict with

commit 46e36683f433 ("serial: earlycon: Extend earlycon command line option to support 64-bit addresses")

Now it is fixed.

Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index b42d7f1..6b18632 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2320,12 +2320,67 @@ static int __init pl011_console_setup(struct console *co, char *options)
        return uart_set_options(&uap->port, co, baud, parity, bits, flow);
 }
 
+/**
+ *     pl011_console_match - non-standard console matching
+ *     @co:      registering console
+ *     @name:    name from console command line
+ *     @idx:     index from console command line
+ *     @options: ptr to option string from console command line
+ *
+ *     Only attempts to match console command lines of the form:
+ *         console=pl011,mmio|mmio32,<addr>[,<options>]
+ *         console=pl011,0x<addr>[,<options>]
+ *     This form is used to register an initial earlycon boot console and
+ *     replace it with the amba_console at pl011 driver init.
+ *
+ *     Performs console setup for a match (as required by interface)
+ *     If no <options> are specified, then assume the h/w is already setup.
+ *
+ *     Returns 0 if console matches; otherwise non-zero to use default matching
+ */
+static int __init pl011_console_match(struct console *co, char *name, int idx,
+                                     char *options)
+{
+       unsigned char iotype;
+       resource_size_t addr;
+       int i;
+
+       if (strcmp(name, "pl011") != 0)
+               return -ENODEV;
+
+       if (uart_parse_earlycon(options, &iotype, &addr, &options))
+               return -ENODEV;
+
+       if (iotype != UPIO_MEM && iotype != UPIO_MEM32)
+               return -ENODEV;
+
+       /* try to match the port specified on the command line */
+       for (i = 0; i < ARRAY_SIZE(amba_ports); i++) {
+               struct uart_port *port;
+
+               if (!amba_ports[i])
+                       continue;
+
+               port = &amba_ports[i]->port;
+
+               if (port->mapbase != addr)
+                       continue;
+
+               co->index = i;
+               port->cons = co;
+               return pl011_console_setup(co, options);
+       }
+
+       return -ENODEV;
+}
+
 static struct uart_driver amba_reg;
 static struct console amba_console = {
        .name           = "ttyAMA",
        .write          = pl011_console_write,
        .device         = uart_console_device,
        .setup          = pl011_console_setup,
+       .match          = pl011_console_match,
        .flags          = CON_PRINTBUFFER,
        .index          = -1,
        .data           = &amba_reg,