[patch 01/15] serial: when guessing, check only active resources, not options

Bjorn Helgaas
2008-05-30T22:49:29Z

[-- Attachment #1: serial-pnp-check-current-resources-not-options --]
[-- Type: text/plain, Size: 2046 bytes --]

Given a completely unknown PNP device, if it happens to have
a modem-like string in its name and it matches a COM port
address, we assume it's a modem.

We used to check the address against all the possible resource
options for the device. But the device is already configured
and enabled, so we only need to check the resources it is
actually using. If we matched an address that wasn't currently
enabled, we would fail anyway as soon as we attempted to touch
the device at that address.

This removes a reference to the struct pnp_dev.{independent,dependent}
fields, which I will soon make private to the PNP subsystem.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>

Index: work10/drivers/serial/8250_pnp.c
===================================================================
--- work10.orig/drivers/serial/8250_pnp.c 2008-05-13 11:28:48.000000000 -0600
+++ work10/drivers/serial/8250_pnp.c 2008-05-13 11:29:16.000000000 -0600
@@ -383,22 +383,19 @@ static int __devinit check_name(char *na
return 0;
}

-static int __devinit check_resources(struct pnp_option *option)
+static int __devinit check_resources(struct pnp_dev *dev)
{
- struct pnp_option *tmp;
- if (!option)
+ resource_size_t port, size;
+
+ if (!pnp_port_valid(dev, 0))
return 0;

- for (tmp = option; tmp; tmp = tmp->next) {
- struct pnp_port *port;
- for (port = tmp->port; port; port = port->next)
- if ((port->size == 8) &&
- ((port->min == 0x2f8) ||
- (port->min == 0x3f8) ||
- (port->min == 0x2e8) ||
- (port->min == 0x3e8)))
- return 1;
- }
+ port = pnp_port_start(dev, 0);
+ size = pnp_port_len(dev, 0);
+
+ if (size == 8 &&
+ (port == 0x2f8 || port == 0x3f8 || port == 0x2e8 || port == 0x3e8))
+ return 1;

return 0;
}
@@ -420,10 +417,7 @@ static int __devinit serial_pnp_guess_bo
(dev->card && check_name(dev->card->name))))
return -ENODEV;

- if (check_resources(dev->independent))
- return 0;
-
- if (check_resources(dev->dependent))
+ if (check_resources(dev))
return 0;

return -ENODEV;

--