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path: root/drivers/gpu/drm/nouveau/nouveau_i2c.c
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Diffstat (limited to 'drivers/gpu/drm/nouveau/nouveau_i2c.c')
-rw-r--r--drivers/gpu/drm/nouveau/nouveau_i2c.c556
1 files changed, 380 insertions, 176 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.c b/drivers/gpu/drm/nouveau/nouveau_i2c.c
index d39b2202b19..820ae7f5204 100644
--- a/drivers/gpu/drm/nouveau/nouveau_i2c.c
+++ b/drivers/gpu/drm/nouveau/nouveau_i2c.c
@@ -29,262 +29,465 @@
#include "nouveau_i2c.h"
#include "nouveau_hw.h"
+#define T_TIMEOUT 2200000
+#define T_RISEFALL 1000
+#define T_HOLD 5000
+
static void
-nv04_i2c_setscl(void *data, int state)
+i2c_drive_scl(void *data, int state)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
- uint8_t val;
-
- val = (NVReadVgaCrtc(dev, 0, i2c->wr) & 0xd0) | (state ? 0x20 : 0);
- NVWriteVgaCrtc(dev, 0, i2c->wr, val | 0x01);
+ struct nouveau_i2c_chan *port = data;
+ if (port->type == 0) {
+ u8 val = NVReadVgaCrtc(port->dev, 0, port->drive);
+ if (state) val |= 0x20;
+ else val &= 0xdf;
+ NVWriteVgaCrtc(port->dev, 0, port->drive, val | 0x01);
+ } else
+ if (port->type == 4) {
+ nv_mask(port->dev, port->drive, 0x2f, state ? 0x21 : 0x01);
+ } else
+ if (port->type == 5) {
+ if (state) port->state |= 0x01;
+ else port->state &= 0xfe;
+ nv_wr32(port->dev, port->drive, 4 | port->state);
+ }
}
static void
-nv04_i2c_setsda(void *data, int state)
+i2c_drive_sda(void *data, int state)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
- uint8_t val;
-
- val = (NVReadVgaCrtc(dev, 0, i2c->wr) & 0xe0) | (state ? 0x10 : 0);
- NVWriteVgaCrtc(dev, 0, i2c->wr, val | 0x01);
+ struct nouveau_i2c_chan *port = data;
+ if (port->type == 0) {
+ u8 val = NVReadVgaCrtc(port->dev, 0, port->drive);
+ if (state) val |= 0x10;
+ else val &= 0xef;
+ NVWriteVgaCrtc(port->dev, 0, port->drive, val | 0x01);
+ } else
+ if (port->type == 4) {
+ nv_mask(port->dev, port->drive, 0x1f, state ? 0x11 : 0x01);
+ } else
+ if (port->type == 5) {
+ if (state) port->state |= 0x02;
+ else port->state &= 0xfd;
+ nv_wr32(port->dev, port->drive, 4 | port->state);
+ }
}
static int
-nv04_i2c_getscl(void *data)
+i2c_sense_scl(void *data)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
-
- return !!(NVReadVgaCrtc(dev, 0, i2c->rd) & 4);
+ struct nouveau_i2c_chan *port = data;
+ struct drm_nouveau_private *dev_priv = port->dev->dev_private;
+ if (port->type == 0) {
+ return !!(NVReadVgaCrtc(port->dev, 0, port->sense) & 0x04);
+ } else
+ if (port->type == 4) {
+ return !!(nv_rd32(port->dev, port->sense) & 0x00040000);
+ } else
+ if (port->type == 5) {
+ if (dev_priv->card_type < NV_D0)
+ return !!(nv_rd32(port->dev, port->sense) & 0x01);
+ else
+ return !!(nv_rd32(port->dev, port->sense) & 0x10);
+ }
+ return 0;
}
static int
-nv04_i2c_getsda(void *data)
+i2c_sense_sda(void *data)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
-
- return !!(NVReadVgaCrtc(dev, 0, i2c->rd) & 8);
+ struct nouveau_i2c_chan *port = data;
+ struct drm_nouveau_private *dev_priv = port->dev->dev_private;
+ if (port->type == 0) {
+ return !!(NVReadVgaCrtc(port->dev, 0, port->sense) & 0x08);
+ } else
+ if (port->type == 4) {
+ return !!(nv_rd32(port->dev, port->sense) & 0x00080000);
+ } else
+ if (port->type == 5) {
+ if (dev_priv->card_type < NV_D0)
+ return !!(nv_rd32(port->dev, port->sense) & 0x02);
+ else
+ return !!(nv_rd32(port->dev, port->sense) & 0x20);
+ }
+ return 0;
}
static void
-nv4e_i2c_setscl(void *data, int state)
+i2c_delay(struct nouveau_i2c_chan *port, u32 nsec)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
- uint8_t val;
-
- val = (nv_rd32(dev, i2c->wr) & 0xd0) | (state ? 0x20 : 0);
- nv_wr32(dev, i2c->wr, val | 0x01);
+ udelay((nsec + 500) / 1000);
}
-static void
-nv4e_i2c_setsda(void *data, int state)
+static bool
+i2c_raise_scl(struct nouveau_i2c_chan *port)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
- uint8_t val;
+ u32 timeout = T_TIMEOUT / T_RISEFALL;
+
+ i2c_drive_scl(port, 1);
+ do {
+ i2c_delay(port, T_RISEFALL);
+ } while (!i2c_sense_scl(port) && --timeout);
- val = (nv_rd32(dev, i2c->wr) & 0xe0) | (state ? 0x10 : 0);
- nv_wr32(dev, i2c->wr, val | 0x01);
+ return timeout != 0;
}
static int
-nv4e_i2c_getscl(void *data)
+i2c_start(struct nouveau_i2c_chan *port)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
+ int ret = 0;
+
+ port->state = i2c_sense_scl(port);
+ port->state |= i2c_sense_sda(port) << 1;
+ if (port->state != 3) {
+ i2c_drive_scl(port, 0);
+ i2c_drive_sda(port, 1);
+ if (!i2c_raise_scl(port))
+ ret = -EBUSY;
+ }
- return !!((nv_rd32(dev, i2c->rd) >> 16) & 4);
+ i2c_drive_sda(port, 0);
+ i2c_delay(port, T_HOLD);
+ i2c_drive_scl(port, 0);
+ i2c_delay(port, T_HOLD);
+ return ret;
}
-static int
-nv4e_i2c_getsda(void *data)
+static void
+i2c_stop(struct nouveau_i2c_chan *port)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
-
- return !!((nv_rd32(dev, i2c->rd) >> 16) & 8);
+ i2c_drive_scl(port, 0);
+ i2c_drive_sda(port, 0);
+ i2c_delay(port, T_RISEFALL);
+
+ i2c_drive_scl(port, 1);
+ i2c_delay(port, T_HOLD);
+ i2c_drive_sda(port, 1);
+ i2c_delay(port, T_HOLD);
}
-static const uint32_t nv50_i2c_port[] = {
- 0x00e138, 0x00e150, 0x00e168, 0x00e180,
- 0x00e254, 0x00e274, 0x00e764, 0x00e780,
- 0x00e79c, 0x00e7b8
-};
-#define NV50_I2C_PORTS ARRAY_SIZE(nv50_i2c_port)
-
static int
-nv50_i2c_getscl(void *data)
+i2c_bitw(struct nouveau_i2c_chan *port, int sda)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
+ i2c_drive_sda(port, sda);
+ i2c_delay(port, T_RISEFALL);
- return !!(nv_rd32(dev, i2c->rd) & 1);
-}
+ if (!i2c_raise_scl(port))
+ return -ETIMEDOUT;
+ i2c_delay(port, T_HOLD);
+ i2c_drive_scl(port, 0);
+ i2c_delay(port, T_HOLD);
+ return 0;
+}
static int
-nv50_i2c_getsda(void *data)
+i2c_bitr(struct nouveau_i2c_chan *port)
{
- struct nouveau_i2c_chan *i2c = data;
- struct drm_device *dev = i2c->dev;
+ int sda;
+
+ i2c_drive_sda(port, 1);
+ i2c_delay(port, T_RISEFALL);
- return !!(nv_rd32(dev, i2c->rd) & 2);
+ if (!i2c_raise_scl(port))
+ return -ETIMEDOUT;
+ i2c_delay(port, T_HOLD);
+
+ sda = i2c_sense_sda(port);
+
+ i2c_drive_scl(port, 0);
+ i2c_delay(port, T_HOLD);
+ return sda;
}
-static void
-nv50_i2c_setscl(void *data, int state)
+static int
+i2c_get_byte(struct nouveau_i2c_chan *port, u8 *byte, bool last)
{
- struct nouveau_i2c_chan *i2c = data;
+ int i, bit;
+
+ *byte = 0;
+ for (i = 7; i >= 0; i--) {
+ bit = i2c_bitr(port);
+ if (bit < 0)
+ return bit;
+ *byte |= bit << i;
+ }
- nv_wr32(i2c->dev, i2c->wr, 4 | (i2c->data ? 2 : 0) | (state ? 1 : 0));
+ return i2c_bitw(port, last ? 1 : 0);
}
-static void
-nv50_i2c_setsda(void *data, int state)
+static int
+i2c_put_byte(struct nouveau_i2c_chan *port, u8 byte)
{
- struct nouveau_i2c_chan *i2c = data;
+ int i, ret;
+ for (i = 7; i >= 0; i--) {
+ ret = i2c_bitw(port, !!(byte & (1 << i)));
+ if (ret < 0)
+ return ret;
+ }
- nv_mask(i2c->dev, i2c->wr, 0x00000006, 4 | (state ? 2 : 0));
- i2c->data = state;
+ ret = i2c_bitr(port);
+ if (ret == 1) /* nack */
+ ret = -EIO;
+ return ret;
}
static int
-nvd0_i2c_getscl(void *data)
+i2c_addr(struct nouveau_i2c_chan *port, struct i2c_msg *msg)
{
- struct nouveau_i2c_chan *i2c = data;
- return !!(nv_rd32(i2c->dev, i2c->rd) & 0x10);
+ u32 addr = msg->addr << 1;
+ if (msg->flags & I2C_M_RD)
+ addr |= 1;
+ return i2c_put_byte(port, addr);
}
static int
-nvd0_i2c_getsda(void *data)
+i2c_bit_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
- struct nouveau_i2c_chan *i2c = data;
- return !!(nv_rd32(i2c->dev, i2c->rd) & 0x20);
+ struct nouveau_i2c_chan *port = (struct nouveau_i2c_chan *)adap;
+ struct i2c_msg *msg = msgs;
+ int ret = 0, mcnt = num;
+
+ while (!ret && mcnt--) {
+ u8 remaining = msg->len;
+ u8 *ptr = msg->buf;
+
+ ret = i2c_start(port);
+ if (ret == 0)
+ ret = i2c_addr(port, msg);
+
+ if (msg->flags & I2C_M_RD) {
+ while (!ret && remaining--)
+ ret = i2c_get_byte(port, ptr++, !remaining);
+ } else {
+ while (!ret && remaining--)
+ ret = i2c_put_byte(port, *ptr++);
+ }
+
+ msg++;
+ }
+
+ i2c_stop(port);
+ return (ret < 0) ? ret : num;
}
-int
-nouveau_i2c_init(struct drm_device *dev, struct dcb_i2c_entry *entry, int index)
+static u32
+i2c_bit_func(struct i2c_adapter *adap)
{
- struct drm_nouveau_private *dev_priv = dev->dev_private;
- struct nouveau_i2c_chan *i2c;
- int ret;
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+const struct i2c_algorithm i2c_bit_algo = {
+ .master_xfer = i2c_bit_xfer,
+ .functionality = i2c_bit_func
+};
+
+static const uint32_t nv50_i2c_port[] = {
+ 0x00e138, 0x00e150, 0x00e168, 0x00e180,
+ 0x00e254, 0x00e274, 0x00e764, 0x00e780,
+ 0x00e79c, 0x00e7b8
+};
- if (entry->chan)
- return -EEXIST;
+static u8 *
+i2c_table(struct drm_device *dev, u8 *version)
+{
+ u8 *dcb = dcb_table(dev), *i2c = NULL;
+ if (dcb) {
+ if (dcb[0] >= 0x15)
+ i2c = ROMPTR(dev, dcb[2]);
+ if (dcb[0] >= 0x30)
+ i2c = ROMPTR(dev, dcb[4]);
+ }
- if (dev_priv->card_type >= NV_50 &&
- dev_priv->card_type <= NV_C0 && entry->read >= NV50_I2C_PORTS) {
- NV_ERROR(dev, "unknown i2c port %d\n", entry->read);
- return -EINVAL;
+ /* early revisions had no version number, use dcb version */
+ if (i2c) {
+ *version = dcb[0];
+ if (*version >= 0x30)
+ *version = i2c[0];
}
- i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
- if (i2c == NULL)
- return -ENOMEM;
-
- switch (entry->port_type) {
- case 0:
- i2c->bit.setsda = nv04_i2c_setsda;
- i2c->bit.setscl = nv04_i2c_setscl;
- i2c->bit.getsda = nv04_i2c_getsda;
- i2c->bit.getscl = nv04_i2c_getscl;
- i2c->rd = entry->read;
- i2c->wr = entry->write;
- break;
- case 4:
- i2c->bit.setsda = nv4e_i2c_setsda;
- i2c->bit.setscl = nv4e_i2c_setscl;
- i2c->bit.getsda = nv4e_i2c_getsda;
- i2c->bit.getscl = nv4e_i2c_getscl;
- i2c->rd = 0x600800 + entry->read;
- i2c->wr = 0x600800 + entry->write;
- break;
- case 5:
- i2c->bit.setsda = nv50_i2c_setsda;
- i2c->bit.setscl = nv50_i2c_setscl;
- if (dev_priv->card_type < NV_D0) {
- i2c->bit.getsda = nv50_i2c_getsda;
- i2c->bit.getscl = nv50_i2c_getscl;
- i2c->rd = nv50_i2c_port[entry->read];
- i2c->wr = i2c->rd;
- } else {
- i2c->bit.getsda = nvd0_i2c_getsda;
- i2c->bit.getscl = nvd0_i2c_getscl;
- i2c->rd = 0x00d014 + (entry->read * 0x20);
- i2c->wr = i2c->rd;
- }
- break;
- case 6:
- i2c->rd = entry->read;
- i2c->wr = entry->write;
- break;
- default:
- NV_ERROR(dev, "DCB I2C port type %d unknown\n",
- entry->port_type);
- kfree(i2c);
- return -EINVAL;
+ return i2c;
+}
+
+int
+nouveau_i2c_init(struct drm_device *dev)
+{
+ struct drm_nouveau_private *dev_priv = dev->dev_private;
+ struct nvbios *bios = &dev_priv->vbios;
+ struct nouveau_i2c_chan *port;
+ u8 *i2c, *entry, legacy[2][4] = {};
+ u8 version, entries, recordlen;
+ int ret, i;
+
+ INIT_LIST_HEAD(&dev_priv->i2c_ports);
+
+ i2c = i2c_table(dev, &version);
+ if (!i2c) {
+ u8 *bmp = &bios->data[bios->offset];
+ if (bios->type != NVBIOS_BMP)
+ return -ENODEV;
+
+ legacy[0][0] = NV_CIO_CRE_DDC_WR__INDEX;
+ legacy[0][1] = NV_CIO_CRE_DDC_STATUS__INDEX;
+ legacy[1][0] = NV_CIO_CRE_DDC0_WR__INDEX;
+ legacy[1][1] = NV_CIO_CRE_DDC0_STATUS__INDEX;
+
+ /* BMP (from v4.0) has i2c info in the structure, it's in a
+ * fixed location on earlier VBIOS
+ */
+ if (bmp[5] < 4)
+ i2c = &bios->data[0x48];
+ else
+ i2c = &bmp[0x36];
+
+ if (i2c[4]) legacy[0][0] = i2c[4];
+ if (i2c[5]) legacy[0][1] = i2c[5];
+ if (i2c[6]) legacy[1][0] = i2c[6];
+ if (i2c[7]) legacy[1][1] = i2c[7];
}
- snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
- "nouveau-%s-%d", pci_name(dev->pdev), index);
- i2c->adapter.owner = THIS_MODULE;
- i2c->adapter.dev.parent = &dev->pdev->dev;
- i2c->dev = dev;
- i2c_set_adapdata(&i2c->adapter, i2c);
-
- if (entry->port_type < 6) {
- i2c->adapter.algo_data = &i2c->bit;
- i2c->bit.udelay = 40;
- i2c->bit.timeout = usecs_to_jiffies(5000);
- i2c->bit.data = i2c;
- ret = i2c_bit_add_bus(&i2c->adapter);
+ if (i2c && version >= 0x30) {
+ entry = i2c[1] + i2c;
+ entries = i2c[2];
+ recordlen = i2c[3];
+ } else
+ if (i2c) {
+ entry = i2c;
+ entries = 16;
+ recordlen = 4;
} else {
- i2c->adapter.algo = &nouveau_dp_i2c_algo;
- ret = i2c_add_adapter(&i2c->adapter);
+ entry = legacy[0];
+ entries = 2;
+ recordlen = 4;
}
- if (ret) {
- NV_ERROR(dev, "Failed to register i2c %d\n", index);
- kfree(i2c);
- return ret;
+ for (i = 0; i < entries; i++, entry += recordlen) {
+ port = kzalloc(sizeof(*port), GFP_KERNEL);
+ if (port == NULL) {
+ nouveau_i2c_fini(dev);
+ return -ENOMEM;
+ }
+
+ port->type = entry[3];
+ if (version < 0x30) {
+ port->type &= 0x07;
+ if (port->type == 0x07)
+ port->type = 0xff;
+ }
+
+ if (port->type == 0xff) {
+ kfree(port);
+ continue;
+ }
+
+ switch (port->type) {
+ case 0: /* NV04:NV50 */
+ port->drive = entry[0];
+ port->sense = entry[1];
+ port->adapter.algo = &i2c_bit_algo;
+ break;
+ case 4: /* NV4E */
+ port->drive = 0x600800 + entry[1];
+ port->sense = port->drive;
+ port->adapter.algo = &i2c_bit_algo;
+ break;
+ case 5: /* NV50- */
+ port->drive = entry[0] & 0x0f;
+ if (dev_priv->card_type < NV_D0) {
+ if (port->drive >= ARRAY_SIZE(nv50_i2c_port))
+ break;
+ port->drive = nv50_i2c_port[port->drive];
+ port->sense = port->drive;
+ } else {
+ port->drive = 0x00d014 + (port->drive * 0x20);
+ port->sense = port->drive;
+ }
+ port->adapter.algo = &i2c_bit_algo;
+ break;
+ case 6: /* NV50- DP AUX */
+ port->drive = entry[0];
+ port->sense = port->drive;
+ port->adapter.algo = &nouveau_dp_i2c_algo;
+ break;
+ default:
+ break;
+ }
+
+ if (!port->adapter.algo) {
+ NV_ERROR(dev, "I2C%d: type %d index %x/%x unknown\n",
+ i, port->type, port->drive, port->sense);
+ kfree(port);
+ continue;
+ }
+
+ snprintf(port->adapter.name, sizeof(port->adapter.name),
+ "nouveau-%s-%d", pci_name(dev->pdev), i);
+ port->adapter.owner = THIS_MODULE;
+ port->adapter.dev.parent = &dev->pdev->dev;
+ port->dev = dev;
+ port->index = i;
+ port->dcb = ROM32(entry[0]);
+ i2c_set_adapdata(&port->adapter, i2c);
+
+ ret = i2c_add_adapter(&port->adapter);
+ if (ret) {
+ NV_ERROR(dev, "I2C%d: failed register: %d\n", i, ret);
+ kfree(port);
+ continue;
+ }
+
+ list_add_tail(&port->head, &dev_priv->i2c_ports);
}
- entry->chan = i2c;
return 0;
}
void
-nouveau_i2c_fini(struct drm_device *dev, struct dcb_i2c_entry *entry)
+nouveau_i2c_fini(struct drm_device *dev)
{
- if (!entry->chan)
- return;
+ struct drm_nouveau_private *dev_priv = dev->dev_private;
+ struct nouveau_i2c_chan *port, *tmp;
- i2c_del_adapter(&entry->chan->adapter);
- kfree(entry->chan);
- entry->chan = NULL;
+ list_for_each_entry_safe(port, tmp, &dev_priv->i2c_ports, head) {
+ i2c_del_adapter(&port->adapter);
+ kfree(port);
+ }
}
struct nouveau_i2c_chan *
-nouveau_i2c_find(struct drm_device *dev, int index)
+nouveau_i2c_find(struct drm_device *dev, u8 index)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
- struct dcb_i2c_entry *i2c = &dev_priv->vbios.dcb.i2c[index];
+ struct nouveau_i2c_chan *port;
+
+ if (index == NV_I2C_DEFAULT(0) ||
+ index == NV_I2C_DEFAULT(1)) {
+ u8 version, *i2c = i2c_table(dev, &version);
+ if (i2c && version >= 0x30) {
+ if (index == NV_I2C_DEFAULT(0))
+ index = (i2c[4] & 0x0f);
+ else
+ index = (i2c[4] & 0xf0) >> 4;
+ } else {
+ index = 2;
+ }
+ }
- if (index >= DCB_MAX_NUM_I2C_ENTRIES)
- return NULL;
+ list_for_each_entry(port, &dev_priv->i2c_ports, head) {
+ if (port->index == index)
+ break;
+ }
- if (dev_priv->card_type >= NV_50 && (i2c->entry & 0x00000100)) {
- uint32_t reg = 0xe500, val;
+ if (&port->head == &dev_priv->i2c_ports)
+ return NULL;
- if (i2c->port_type == 6) {
- reg += i2c->read * 0x50;
+ if (dev_priv->card_type >= NV_50 && (port->dcb & 0x00000100)) {
+ u32 reg = 0x00e500, val;
+ if (port->type == 6) {
+ reg += port->drive * 0x50;
val = 0x2002;
} else {
- reg += ((i2c->entry & 0x1e00) >> 9) * 0x50;
+ reg += ((port->dcb & 0x1e00) >> 9) * 0x50;
val = 0xe001;
}
@@ -294,9 +497,7 @@ nouveau_i2c_find(struct drm_device *dev, int index)
nv_mask(dev, reg + 0x00, 0x0000f003, val);
}
- if (!i2c->chan && nouveau_i2c_init(dev, i2c, index))
- return NULL;
- return i2c->chan;
+ return port;
}
bool
@@ -331,9 +532,13 @@ nouveau_i2c_identify(struct drm_device *dev, const char *what,
struct nouveau_i2c_chan *i2c = nouveau_i2c_find(dev, index);
int i;
- NV_DEBUG(dev, "Probing %ss on I2C bus: %d\n", what, index);
+ if (!i2c) {
+ NV_DEBUG(dev, "No bus when probing %s on %d\n", what, index);
+ return -ENODEV;
+ }
- for (i = 0; i2c && info[i].addr; i++) {
+ NV_DEBUG(dev, "Probing %ss on I2C bus: %d\n", what, i2c->index);
+ for (i = 0; info[i].addr; i++) {
if (nouveau_probe_i2c_addr(i2c, info[i].addr) &&
(!match || match(i2c, &info[i]))) {
NV_INFO(dev, "Detected %s: %s\n", what, info[i].type);
@@ -342,6 +547,5 @@ nouveau_i2c_identify(struct drm_device *dev, const char *what,
}
NV_DEBUG(dev, "No devices found.\n");
-
return -ENODEV;
}