PNP SMCf010 quirk: auto-config device if BIOS left it broken

Some HP firmware leaves the SMCf010 IRDA device incompletely configured, or
reports the wrong resources in _CRS.  As a workaround, when we find such a
device, try to auto-configure the device.

This ignores the _CRS data, picks a config from _PRS, and runs _SRS to
configure the device.  This makes smsc-ircc2 work correctly with PNP
resources (with no preconfiguration!) on all the machines I tested.

I think Windows does something like this by default for all devices,
so we should consider doing the same thing in Linux.

This patch addresses part of the 2.6.22 regression:
    "no irda0 interface (2.6.21 was OK), smsc does not find chip"
It fixes smsc-ircc2 PNP device detection on HP nc6000, nc6220, nw8000,
nw8240, and possibly other machines.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: "Linus Walleij (LD/EAB)" <linus.walleij@ericsson.com>
Cc: Andrey Borzenkov <arvidjaar@mail.ru>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 48 insertions, 18 deletions

diff --git a/drivers/pnp/quirks.c b/drivers/pnp/quirks.c
index 277df50c89ae..967a8e22b2da 100644
--- a/drivers/pnp/quirks.c
+++ b/drivers/pnp/quirks.c
@@ -107,31 +107,61 @@ static void quirk_sb16audio_resources(struct pnp_dev *dev)
         return;
 }
 
-static void quirk_smc_enable(struct pnp_dev *dev)
+static int quirk_smc_fir_enabled(struct pnp_dev *dev)
 {
-        unsigned int firbase;
+        unsigned long firbase;
+        u8 bank, high, low, chip;
+
+        if (!pnp_port_valid(dev, 1))
+                return 0;
+
+        firbase = pnp_port_start(dev, 1);
+
+        /* Select register bank 3 */
+        bank = inb(firbase + 7);
+        bank &= 0xf0;
+        bank |= 3;
+        outb(bank, firbase + 7);
+
+        high = inb(firbase + 0);
+        low  = inb(firbase + 1);
+        chip = inb(firbase + 2);
+
+        /* This corresponds to the check in smsc_ircc_present() */
+        if (high == 0x10 && low == 0xb8 && (chip == 0xf1 || chip == 0xf2))
+                return 1;
+
+        return 0;
+}
 
-        if (!dev->active || !pnp_port_valid(dev, 1))
+static void quirk_smc_enable(struct pnp_dev *dev)
+{
+        /*
+         * If the BIOS left the device disabled, or it is enabled and
+         * responding correctly, we're in good shape.
+         */
+        if (!dev->active || quirk_smc_fir_enabled(dev))
                 return;
 
         /*
-         * On the HP/Compaq nw8240 (and probably other similar machines),
-         * there is an SMCF010 device with two I/O port regions:
-         *
-         *      0x3e8-0x3ef SIR
-         *      0x100-0x10f FIR
+         * Sometimes the BIOS claims the device is enabled, but it reports
+         * the wrong FIR resources or doesn't properly configure ISA or LPC
+         * bridges on the way to the device.
          *
-         * _STA reports the device is enabled, but in fact, the BIOS
-         * neglects to enable the FIR range.  Fortunately, it does fully
-         * enable the device if we call _SRS.
+         * HP nc6000 and nc8000/nw8000 laptops have known problems like
+         * this.  Fortunately, they do fix things up if we auto-configure
+         * the device using its _PRS and _SRS methods.
          */
-        firbase = pnp_port_start(dev, 1);
-        if (inb(firbase + 0x7 /* IRCC_MASTER */) == 0xff) {
-                pnp_err("%s (%s) enabled but not responding, disabling and "
-                        "re-enabling", dev->dev.bus_id, pnp_dev_name(dev));
-                pnp_disable_dev(dev);
-                pnp_activate_dev(dev);
-        }
+        dev_err(&dev->dev, "%s device not responding, auto-configuring "
+                "resources\n", dev->id->id);
+
+        pnp_disable_dev(dev);
+        pnp_init_resource_table(&dev->res);
+        pnp_auto_config_dev(dev);
+        pnp_activate_dev(dev);
+
+        if (!quirk_smc_fir_enabled(dev))
+                dev_err(&dev->dev, "giving up; try \"smsc-ircc2.nopnp\"\n");
 }