b43: Fix chip access validation for new devices

This fixes chip access validation for newer devices
(4318 and up, I think)

This patch fixes probing of a PCMCIA based 4318 device.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 25 insertions, 15 deletions

diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index f4c14272332b..6b3013c2d96d 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -2408,32 +2408,42 @@ static void b43_periodic_tasks_setup(struct b43_wldev *dev)
         queue_delayed_work(dev->wl->hw->workqueue, work, 0);
 }
 
-/* Validate access to the chip (SHM) */
+/* Check if communication with the device works correctly. */
 static int b43_validate_chipaccess(struct b43_wldev *dev)
 {
-        u32 value;
-        u32 shm_backup;
+        u32 v, backup;
 
-        shm_backup = b43_shm_read32(dev, B43_SHM_SHARED, 0);
-        b43_shm_write32(dev, B43_SHM_SHARED, 0, 0xAA5555AA);
-        if (b43_shm_read32(dev, B43_SHM_SHARED, 0) != 0xAA5555AA)
-                goto error;
+        backup = b43_shm_read32(dev, B43_SHM_SHARED, 0);
+
+        /* Check for read/write and endianness problems. */
         b43_shm_write32(dev, B43_SHM_SHARED, 0, 0x55AAAA55);
         if (b43_shm_read32(dev, B43_SHM_SHARED, 0) != 0x55AAAA55)
                 goto error;
-        b43_shm_write32(dev, B43_SHM_SHARED, 0, shm_backup);
-
-        value = b43_read32(dev, B43_MMIO_MACCTL);
-        if ((value | B43_MACCTL_GMODE) !=
-            (B43_MACCTL_GMODE | B43_MACCTL_IHR_ENABLED))
+        b43_shm_write32(dev, B43_SHM_SHARED, 0, 0xAA5555AA);
+        if (b43_shm_read32(dev, B43_SHM_SHARED, 0) != 0xAA5555AA)
                 goto error;
 
-        value = b43_read32(dev, B43_MMIO_GEN_IRQ_REASON);
-        if (value)
+        b43_shm_write32(dev, B43_SHM_SHARED, 0, backup);
+
+        if ((dev->dev->id.revision >= 3) && (dev->dev->id.revision <= 10)) {
+                /* The 32bit register shadows the two 16bit registers
+                 * with update sideeffects. Validate this. */
+                b43_write16(dev, B43_MMIO_TSF_CFP_START, 0xAAAA);
+                b43_write32(dev, B43_MMIO_TSF_CFP_START, 0xCCCCBBBB);
+                if (b43_read16(dev, B43_MMIO_TSF_CFP_START_LOW) != 0xBBBB)
+                        goto error;
+                if (b43_read16(dev, B43_MMIO_TSF_CFP_START_HIGH) != 0xCCCC)
+                        goto error;
+        }
+        b43_write32(dev, B43_MMIO_TSF_CFP_START, 0);
+
+        v = b43_read32(dev, B43_MMIO_MACCTL);
+        v |= B43_MACCTL_GMODE;
+        if (v != (B43_MACCTL_GMODE | B43_MACCTL_IHR_ENABLED))
                 goto error;
 
         return 0;
-      error:
+error:
         b43err(dev->wl, "Failed to validate the chipaccess\n");
         return -ENODEV;
 }