diff options
Diffstat (limited to 'drivers/gpu/drm/drm_dp_dual_mode_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_dual_mode_helper.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_dual_mode_helper.c b/drivers/gpu/drm/drm_dp_dual_mode_helper.c index a7b2a751f6fe..488355bdafb9 100644 --- a/drivers/gpu/drm/drm_dp_dual_mode_helper.c +++ b/drivers/gpu/drm/drm_dp_dual_mode_helper.c @@ -148,6 +148,14 @@ static bool is_type2_adaptor(uint8_t adaptor_id) 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 @@ -203,6 +211,8 @@ 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_ADAPTOR_ID, &adaptor_id, sizeof(adaptor_id)); 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; @@ -364,3 +374,96 @@ 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, ¤t_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); |