drm/nouveau: Add some generic I2C gadget detection code.

Clean up and move the external TV encoder detection code to
nouveau_i2c.c, it's also going to be useful for external TMDS and DDC
detection.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

4 files changed, 75 insertions, 99 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 7f749d281df9..27df0063131e 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -139,26 +139,10 @@ nouveau_connector_ddc_detect(struct drm_connector *connector,
                              struct nouveau_encoder **pnv_encoder)
 {
         struct drm_device *dev = connector->dev;
-        uint8_t out_buf[] = { 0x0, 0x0}, buf[2];
         int ret, flags, i;
 
-        struct i2c_msg msgs[] = {
-                {
-                        .addr = 0x50,
-                        .flags = 0,
-                        .len = 1,
-                        .buf = out_buf,
-                },
-                {
-                        .addr = 0x50,
-                        .flags = I2C_M_RD,
-                        .len = 1,
-                        .buf = buf,
-                }
-        };
-
         for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
-                struct nouveau_i2c_chan *i2c = NULL;
+                struct nouveau_i2c_chan *i2c;
                 struct nouveau_encoder *nv_encoder;
                 struct drm_mode_object *obj;
                 int id;
@@ -178,10 +162,10 @@ nouveau_connector_ddc_detect(struct drm_connector *connector,
                         continue;
 
                 nouveau_connector_ddc_prepare(connector, &flags);
-                ret = i2c_transfer(&i2c->adapter, msgs, 2);
+                ret = nouveau_probe_i2c_addr(i2c, 0x50);
                 nouveau_connector_ddc_finish(connector, flags);
 
-                if (ret == 2) {
+                if (ret) {
                         *pnv_encoder = nv_encoder;
                         return i2c;
                 }
diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.c b/drivers/gpu/drm/nouveau/nouveau_i2c.c
index 316a3c7e6eb4..97ba89ef42a0 100644
--- a/drivers/gpu/drm/nouveau/nouveau_i2c.c
+++ b/drivers/gpu/drm/nouveau/nouveau_i2c.c
@@ -278,3 +278,37 @@ nouveau_i2c_find(struct drm_device *dev, int index)
         return i2c->chan;
 }
 
+bool
+nouveau_probe_i2c_addr(struct nouveau_i2c_chan *i2c, int addr)
+{
+        struct i2c_msg msg = {
+                .addr = addr,
+                .len = 0,
+        };
+
+        return i2c_transfer(&i2c->adapter, &msg, 1) == 1;
+}
+
+int
+nouveau_i2c_identify(struct drm_device *dev, const char *what,
+                     struct i2c_board_info *info, int index)
+{
+        struct nouveau_i2c_chan *i2c = nouveau_i2c_find(dev, index);
+        int was_locked, i;
+
+        was_locked = NVLockVgaCrtcs(dev, false);
+        NV_DEBUG(dev, "Probing %ss on I2C bus: %d\n", what, index);
+
+        for (i = 0; info[i].addr; i++) {
+                if (nouveau_probe_i2c_addr(i2c, info[i].addr)) {
+                        NV_INFO(dev, "Detected %s: %s\n", what, info[i].type);
+                        goto out;
+                }
+        }
+
+        NV_DEBUG(dev, "No devices found.\n");
+out:
+        NVLockVgaCrtcs(dev, was_locked);
+
+        return info[i].addr ? i : -ENODEV;
+}
diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.h b/drivers/gpu/drm/nouveau/nouveau_i2c.h
index c8eaf7a9fcbb..6dd2f8713cd1 100644
--- a/drivers/gpu/drm/nouveau/nouveau_i2c.h
+++ b/drivers/gpu/drm/nouveau/nouveau_i2c.h
@@ -45,6 +45,9 @@ struct nouveau_i2c_chan {
 int nouveau_i2c_init(struct drm_device *, struct dcb_i2c_entry *, int index);
 void nouveau_i2c_fini(struct drm_device *, struct dcb_i2c_entry *);
 struct nouveau_i2c_chan *nouveau_i2c_find(struct drm_device *, int index);
+bool nouveau_probe_i2c_addr(struct nouveau_i2c_chan *i2c, int addr);
+int nouveau_i2c_identify(struct drm_device *dev, const char *what,
+                         struct i2c_board_info *info, int index);
 
 int nouveau_dp_i2c_aux_ch(struct i2c_adapter *, int mode, uint8_t write_byte,
                           uint8_t *read_byte);
diff --git a/drivers/gpu/drm/nouveau/nv04_tv.c b/drivers/gpu/drm/nouveau/nv04_tv.c
index 84b5954a8efb..8de1eef3594a 100644
--- a/drivers/gpu/drm/nouveau/nv04_tv.c
+++ b/drivers/gpu/drm/nouveau/nv04_tv.c
@@ -34,69 +34,26 @@
 
 #include "i2c/ch7006.h"
 
-static struct {
-        struct i2c_board_info board_info;
-        struct drm_encoder_funcs funcs;
-        struct drm_encoder_helper_funcs hfuncs;
-        void *params;
-
-} nv04_tv_encoder_info[] = {
+static struct i2c_board_info nv04_tv_encoder_info[] = {
         {
-                .board_info = { I2C_BOARD_INFO("ch7006", 0x75) },
-                .params = &(struct ch7006_encoder_params) {
+                I2C_BOARD_INFO("ch7006", 0x75),
+                .platform_data = &(struct ch7006_encoder_params) {
                         CH7006_FORMAT_RGB24m12I, CH7006_CLOCK_MASTER,
                         0, 0, 0,
                         CH7006_SYNC_SLAVE, CH7006_SYNC_SEPARATED,
                         CH7006_POUT_3_3V, CH7006_ACTIVE_HSYNC
-                },
+                }
         },
+        { }
 };
 
-static bool probe_i2c_addr(struct i2c_adapter *adapter, int addr)
-{
-        struct i2c_msg msg = {
-                .addr = addr,
-                .len = 0,
-        };
-
-        return i2c_transfer(adapter, &msg, 1) == 1;
-}
-
 int nv04_tv_identify(struct drm_device *dev, int i2c_index)
 {
-        struct nouveau_i2c_chan *i2c;
-        bool was_locked;
-        int i, ret;
-
-        NV_TRACE(dev, "Probing TV encoders on I2C bus: %d\n", i2c_index);
-
-        i2c = nouveau_i2c_find(dev, i2c_index);
-        if (!i2c)
-                return -ENODEV;
-
-        was_locked = NVLockVgaCrtcs(dev, false);
-
-        for (i = 0; i < ARRAY_SIZE(nv04_tv_encoder_info); i++) {
-                if (probe_i2c_addr(&i2c->adapter,
-                                   nv04_tv_encoder_info[i].board_info.addr)) {
-                        ret = i;
-                        break;
-                }
-        }
-
-        if (i < ARRAY_SIZE(nv04_tv_encoder_info)) {
-                NV_TRACE(dev, "Detected TV encoder: %s\n",
-                         nv04_tv_encoder_info[i].board_info.type);
-
-        } else {
-                NV_TRACE(dev, "No TV encoders found.\n");
-                i = -ENODEV;
-        }
-
-        NVLockVgaCrtcs(dev, was_locked);
-        return i;
+        return nouveau_i2c_identify(dev, "TV encoder",
+                                    nv04_tv_encoder_info, i2c_index);
 }
 
+
 #define PLLSEL_TV_CRTC1_MASK                            \
         (NV_PRAMDAC_PLL_COEFF_SELECT_TV_VSCLK1          \
          | NV_PRAMDAC_PLL_COEFF_SELECT_TV_PCLK1)
@@ -214,32 +171,33 @@ static void nv04_tv_commit(struct drm_encoder *encoder)
 
 static void nv04_tv_destroy(struct drm_encoder *encoder)
 {
-        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
-
         to_encoder_slave(encoder)->slave_funcs->destroy(encoder);
 
         drm_encoder_cleanup(encoder);
 
-        kfree(nv_encoder);
+        kfree(encoder->helper_private);
+        kfree(nouveau_encoder(encoder));
 }
 
+static const struct drm_encoder_funcs nv04_tv_funcs = {
+        .destroy = nv04_tv_destroy,
+};
+
 int
 nv04_tv_create(struct drm_connector *connector, struct dcb_entry *entry)
 {
         struct nouveau_encoder *nv_encoder;
         struct drm_encoder *encoder;
         struct drm_device *dev = connector->dev;
-        struct drm_nouveau_private *dev_priv = dev->dev_private;
-        struct i2c_adapter *adap;
-        struct drm_encoder_funcs *funcs = NULL;
-        struct drm_encoder_helper_funcs *hfuncs = NULL;
-        struct drm_encoder_slave_funcs *sfuncs = NULL;
-        int i2c_index = entry->i2c_index;
+        struct drm_encoder_helper_funcs *hfuncs;
+        struct drm_encoder_slave_funcs *sfuncs;
+        struct nouveau_i2c_chan *i2c =
+                nouveau_i2c_find(dev, entry->i2c_index);
         int type, ret;
         bool was_locked;
 
         /* Ensure that we can talk to this encoder */
-        type = nv04_tv_identify(dev, i2c_index);
+        type = nv04_tv_identify(dev, entry->i2c_index);
         if (type < 0)
                 return type;
 
@@ -248,41 +206,37 @@ nv04_tv_create(struct drm_connector *connector, struct dcb_entry *entry)
         if (!nv_encoder)
                 return -ENOMEM;
 
+        hfuncs = kzalloc(sizeof(*hfuncs), GFP_KERNEL);
+        if (!hfuncs) {
+                ret = -ENOMEM;
+                goto fail_free;
+        }
+
         /* Initialize the common members */
         encoder = to_drm_encoder(nv_encoder);
 
-        funcs = &nv04_tv_encoder_info[type].funcs;
-        hfuncs = &nv04_tv_encoder_info[type].hfuncs;
-
-        drm_encoder_init(dev, encoder, funcs, DRM_MODE_ENCODER_TVDAC);
+        drm_encoder_init(dev, encoder, &nv04_tv_funcs, DRM_MODE_ENCODER_TVDAC);
         drm_encoder_helper_add(encoder, hfuncs);
 
         encoder->possible_crtcs = entry->heads;
         encoder->possible_clones = 0;
-
         nv_encoder->dcb = entry;
         nv_encoder->or = ffs(entry->or) - 1;
 
         /* Run the slave-specific initialization */
-        adap = &dev_priv->vbios.dcb.i2c[i2c_index].chan->adapter;
-
         was_locked = NVLockVgaCrtcs(dev, false);
 
-        ret = drm_i2c_encoder_init(dev, to_encoder_slave(encoder), adap,
-                                   &nv04_tv_encoder_info[type].board_info);
+        ret = drm_i2c_encoder_init(dev, to_encoder_slave(encoder),
+                                   &i2c->adapter, &nv04_tv_encoder_info[type]);
 
         NVLockVgaCrtcs(dev, was_locked);
 
         if (ret < 0)
-                goto fail;
+                goto fail_cleanup;
 
         /* Fill the function pointers */
         sfuncs = to_encoder_slave(encoder)->slave_funcs;
 
-        *funcs = (struct drm_encoder_funcs) {
-                .destroy = nv04_tv_destroy,
-        };
-
         *hfuncs = (struct drm_encoder_helper_funcs) {
                 .dpms = nv04_tv_dpms,
                 .save = sfuncs->save,
@@ -294,16 +248,17 @@ nv04_tv_create(struct drm_connector *connector, struct dcb_entry *entry)
                 .detect = sfuncs->detect,
         };
 
-        /* Set the slave encoder configuration */
-        sfuncs->set_config(encoder, nv04_tv_encoder_info[type].params);
+        /* Attach it to the specified connector. */
+        sfuncs->set_config(encoder, nv04_tv_encoder_info[type].platform_data);
         sfuncs->create_resources(encoder, connector);
-
         drm_mode_connector_attach_encoder(connector, encoder);
+
         return 0;
 
-fail:
+fail_cleanup:
         drm_encoder_cleanup(encoder);
-
+        kfree(hfuncs);
+fail_free:
         kfree(nv_encoder);
         return ret;
 }