drm/nouveau/mxm: implement ROM shadow method
Untested, -ENOHW.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_mxm.c b/drivers/gpu/drm/nouveau/nouveau_mxm.c
index 840c88f..8bccddf 100644
--- a/drivers/gpu/drm/nouveau/nouveau_mxm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_mxm.c
@@ -471,8 +471,47 @@
}
static bool
+mxm_shadow_rom_fetch(struct nouveau_i2c_chan *i2c, u8 addr,
+ u8 offset, u8 size, u8 *data)
+{
+ struct i2c_msg msgs[] = {
+ { .addr = addr, .flags = 0, .len = 1, .buf = &offset },
+ { .addr = addr, .flags = I2C_M_RD, .len = size, .buf = data, },
+ };
+
+ return i2c_transfer(&i2c->adapter, msgs, 2) == 2;
+}
+
+static bool
mxm_shadow_rom(struct drm_device *dev, u8 version)
{
+ struct drm_nouveau_private *dev_priv = dev->dev_private;
+ struct nouveau_i2c_chan *i2c = NULL;
+ u8 i2cidx, mxms[6], addr, size;
+
+ i2cidx = mxm_ddc_map(dev, 1 /* LVDS_DDC */) & 0x0f;
+ if (i2cidx < 0x0f)
+ i2c = nouveau_i2c_find(dev, i2cidx);
+ if (!i2c)
+ return false;
+
+ addr = 0x54;
+ if (!mxm_shadow_rom_fetch(i2c, addr, 0, 6, mxms)) {
+ addr = 0x56;
+ if (!mxm_shadow_rom_fetch(i2c, addr, 0, 6, mxms))
+ return false;
+ }
+
+ dev_priv->mxms = mxms;
+ size = mxms_headerlen(dev) + mxms_structlen(dev);
+ dev_priv->mxms = kmalloc(size, GFP_KERNEL);
+
+ if (dev_priv->mxms &&
+ mxm_shadow_rom_fetch(i2c, addr, 0, size, dev_priv->mxms))
+ return true;
+
+ kfree(dev_priv->mxms);
+ dev_priv->mxms = NULL;
return false;
}