Merge tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

[karo-tx-linux.git] / drivers / gpu / drm / drm_dp_dual_mode_helper.c

diff --git a/drivers/gpu/drm/drm_dp_dual_mode_helper.c b/drivers/gpu/drm/drm_dp_dual_mode_helper.c
index a7b2a751f6fe77ac1409c4d92b55fd475db7c09a..e025639662718cc6441a897ffa713fc5404cc66e 100644 (file)
--- a/drivers/gpu/drm/drm_dp_dual_mode_helper.c
+++ b/drivers/gpu/drm/drm_dp_dual_mode_helper.c
@@ -142,12 +142,25 @@ static bool is_hdmi_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN])
                      sizeof(dp_dual_mode_hdmi_id)) == 0;
 }
 
+static bool is_type1_adaptor(uint8_t adaptor_id)
+{
+       return adaptor_id == 0 || adaptor_id == 0xff;
+}
+
 static bool is_type2_adaptor(uint8_t adaptor_id)
 {
        return adaptor_id == (DP_DUAL_MODE_TYPE_TYPE2 |
                              DP_DUAL_MODE_REV_TYPE2);
 }
 
+static bool is_lspcon_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN],
+                             const uint8_t adaptor_id)
+{
+       return is_hdmi_adaptor(hdmi_id) &&
+               (adaptor_id == (DP_DUAL_MODE_TYPE_TYPE2 |
+                DP_DUAL_MODE_TYPE_HAS_DPCD));
+}
+
 /**
  * drm_dp_dual_mode_detect - Identify the DP dual mode adaptor
  * @adapter: I2C adapter for the DDC bus
@@ -185,6 +198,8 @@ enum drm_dp_dual_mode_type drm_dp_dual_mode_detect(struct i2c_adapter *adapter)
         */
        ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_HDMI_ID,
                                    hdmi_id, sizeof(hdmi_id));
+       DRM_DEBUG_KMS("DP dual mode HDMI ID: %*pE (err %zd)\n",
+                     ret ? 0 : (int)sizeof(hdmi_id), hdmi_id, ret);
        if (ret)
                return DRM_DP_DUAL_MODE_UNKNOWN;
 
@@ -202,13 +217,26 @@ enum drm_dp_dual_mode_type drm_dp_dual_mode_detect(struct i2c_adapter *adapter)
         */
        ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_ADAPTOR_ID,
                                    &adaptor_id, sizeof(adaptor_id));
+       DRM_DEBUG_KMS("DP dual mode adaptor ID: %02x (err %zd)\n",
+                     adaptor_id, ret);
        if (ret == 0) {
+               if (is_lspcon_adaptor(hdmi_id, adaptor_id))
+                       return DRM_DP_DUAL_MODE_LSPCON;
                if (is_type2_adaptor(adaptor_id)) {
                        if (is_hdmi_adaptor(hdmi_id))
                                return DRM_DP_DUAL_MODE_TYPE2_HDMI;
                        else
                                return DRM_DP_DUAL_MODE_TYPE2_DVI;
                }
+               /*
+                * If neither a proper type 1 ID nor a broken type 1 adaptor
+                * as described above, assume type 1, but let the user know
+                * that we may have misdetected the type.
+                */
+               if (!is_type1_adaptor(adaptor_id) && adaptor_id != hdmi_id[0])
+                       DRM_ERROR("Unexpected DP dual mode adaptor ID %02x\n",
+                                 adaptor_id);
+
        }
 
        if (is_hdmi_adaptor(hdmi_id))
@@ -364,3 +392,96 @@ const char *drm_dp_get_dual_mode_type_name(enum drm_dp_dual_mode_type type)
        }
 }
 EXPORT_SYMBOL(drm_dp_get_dual_mode_type_name);
+
+/**
+ * drm_lspcon_get_mode: Get LSPCON's current mode of operation by
+ * reading offset (0x80, 0x41)
+ * @adapter: I2C-over-aux adapter
+ * @mode: current lspcon mode of operation output variable
+ *
+ * Returns:
+ * 0 on success, sets the current_mode value to appropriate mode
+ * -error on failure
+ */
+int drm_lspcon_get_mode(struct i2c_adapter *adapter,
+                       enum drm_lspcon_mode *mode)
+{
+       u8 data;
+       int ret = 0;
+
+       if (!mode) {
+               DRM_ERROR("NULL input\n");
+               return -EINVAL;
+       }
+
+       /* Read Status: i2c over aux */
+       ret = drm_dp_dual_mode_read(adapter, DP_DUAL_MODE_LSPCON_CURRENT_MODE,
+                                   &data, sizeof(data));
+       if (ret < 0) {
+               DRM_ERROR("LSPCON read(0x80, 0x41) failed\n");
+               return -EFAULT;
+       }
+
+       if (data & DP_DUAL_MODE_LSPCON_MODE_PCON)
+               *mode = DRM_LSPCON_MODE_PCON;
+       else
+               *mode = DRM_LSPCON_MODE_LS;
+       return 0;
+}
+EXPORT_SYMBOL(drm_lspcon_get_mode);
+
+/**
+ * drm_lspcon_set_mode: Change LSPCON's mode of operation by
+ * writing offset (0x80, 0x40)
+ * @adapter: I2C-over-aux adapter
+ * @mode: required mode of operation
+ *
+ * Returns:
+ * 0 on success, -error on failure/timeout
+ */
+int drm_lspcon_set_mode(struct i2c_adapter *adapter,
+                       enum drm_lspcon_mode mode)
+{
+       u8 data = 0;
+       int ret;
+       int time_out = 200;
+       enum drm_lspcon_mode current_mode;
+
+       if (mode == DRM_LSPCON_MODE_PCON)
+               data = DP_DUAL_MODE_LSPCON_MODE_PCON;
+
+       /* Change mode */
+       ret = drm_dp_dual_mode_write(adapter, DP_DUAL_MODE_LSPCON_MODE_CHANGE,
+                                    &data, sizeof(data));
+       if (ret < 0) {
+               DRM_ERROR("LSPCON mode change failed\n");
+               return ret;
+       }
+
+       /*
+        * Confirm mode change by reading the status bit.
+        * Sometimes, it takes a while to change the mode,
+        * so wait and retry until time out or done.
+        */
+       do {
+               ret = drm_lspcon_get_mode(adapter, &current_mode);
+               if (ret) {
+                       DRM_ERROR("can't confirm LSPCON mode change\n");
+                       return ret;
+               } else {
+                       if (current_mode != mode) {
+                               msleep(10);
+                               time_out -= 10;
+                       } else {
+                               DRM_DEBUG_KMS("LSPCON mode changed to %s\n",
+                                               mode == DRM_LSPCON_MODE_LS ?
+                                               "LS" : "PCON");
+                               return 0;
+                       }
+               }
+       } while (time_out);
+
+       DRM_ERROR("LSPCON mode change timed out\n");
+       return -ETIMEDOUT;
+}
+EXPORT_SYMBOL(drm_lspcon_set_mode);