/* * NXP PTN3460 DP/LVDS bridge driver * * Copyright (C) 2013 Google, Inc. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define PTN3460_EDID_ADDR 0x0 #define PTN3460_EDID_EMULATION_ADDR 0x84 #define PTN3460_EDID_ENABLE_EMULATION 0 #define PTN3460_EDID_EMULATION_SELECTION 1 #define PTN3460_EDID_SRAM_LOAD_ADDR 0x85 struct ptn3460_bridge { struct drm_connector connector; struct i2c_client *client; struct drm_bridge bridge; struct edid *edid; struct drm_panel *panel; struct gpio_desc *gpio_pd_n; struct gpio_desc *gpio_rst_n; u32 edid_emulation; bool enabled; }; static inline struct ptn3460_bridge * bridge_to_ptn3460(struct drm_bridge *bridge) { return container_of(bridge, struct ptn3460_bridge, bridge); } static inline struct ptn3460_bridge * connector_to_ptn3460(struct drm_connector *connector) { return container_of(connector, struct ptn3460_bridge, connector); } static int ptn3460_read_bytes(struct ptn3460_bridge *ptn_bridge, char addr, u8 *buf, int len) { int ret; ret = i2c_master_send(ptn_bridge->client, &addr, 1); if (ret <= 0) { DRM_ERROR("Failed to send i2c command, ret=%d\n", ret); return ret; } ret = i2c_master_recv(ptn_bridge->client, buf, len); if (ret <= 0) { DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret); return ret; } return 0; } static int ptn3460_write_byte(struct ptn3460_bridge *ptn_bridge, char addr, char val) { int ret; char buf[2]; buf[0] = addr; buf[1] = val; ret = i2c_master_send(ptn_bridge->client, buf, ARRAY_SIZE(buf)); if (ret <= 0) { DRM_ERROR("Failed to send i2c command, ret=%d\n", ret); return ret; } return 0; } static int ptn3460_select_edid(struct ptn3460_bridge *ptn_bridge) { int ret; char val; /* Load the selected edid into SRAM (accessed at PTN3460_EDID_ADDR) */ ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_SRAM_LOAD_ADDR, ptn_bridge->edid_emulation); if (ret) { DRM_ERROR("Failed to transfer EDID to sram, ret=%d\n", ret); return ret; } /* Enable EDID emulation and select the desired EDID */ val = 1 << PTN3460_EDID_ENABLE_EMULATION | ptn_bridge->edid_emulation << PTN3460_EDID_EMULATION_SELECTION; ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_EMULATION_ADDR, val); if (ret) { DRM_ERROR("Failed to write EDID value, ret=%d\n", ret); return ret; } return 0; } static void ptn3460_pre_enable(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge); int ret; if (ptn_bridge->enabled) return; gpiod_set_value(ptn_bridge->gpio_pd_n, 1); gpiod_set_value(ptn_bridge->gpio_rst_n, 0); usleep_range(10, 20); gpiod_set_value(ptn_bridge->gpio_rst_n, 1); if (drm_panel_prepare(ptn_bridge->panel)) { DRM_ERROR("failed to prepare panel\n"); return; } /* * There's a bug in the PTN chip where it falsely asserts hotplug before * it is fully functional. We're forced to wait for the maximum start up * time specified in the chip's datasheet to make sure we're really up. */ msleep(90); ret = ptn3460_select_edid(ptn_bridge); if (ret) DRM_ERROR("Select EDID failed ret=%d\n", ret); ptn_bridge->enabled = true; } static void ptn3460_enable(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge); if (drm_panel_enable(ptn_bridge->panel)) { DRM_ERROR("failed to enable panel\n"); return; } } static void ptn3460_disable(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge); if (!ptn_bridge->enabled) return; ptn_bridge->enabled = false; if (drm_panel_disable(ptn_bridge->panel)) { DRM_ERROR("failed to disable panel\n"); return; } gpiod_set_value(ptn_bridge->gpio_rst_n, 1); gpiod_set_value(ptn_bridge->gpio_pd_n, 0); } static void ptn3460_post_disable(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge); if (drm_panel_unprepare(ptn_bridge->panel)) { DRM_ERROR("failed to unprepare panel\n"); return; } } static int ptn3460_get_modes(struct drm_connector *connector) { struct ptn3460_bridge *ptn_bridge; u8 *edid; int ret, num_modes = 0; bool power_off; ptn_bridge = connector_to_ptn3460(connector); if (ptn_bridge->edid) return drm_add_edid_modes(connector, ptn_bridge->edid); power_off = !ptn_bridge->enabled; ptn3460_pre_enable(&ptn_bridge->bridge); edid = kmalloc(EDID_LENGTH, GFP_KERNEL); if (!edid) { DRM_ERROR("Failed to allocate EDID\n"); return 0; } ret = ptn3460_read_bytes(ptn_bridge, PTN3460_EDID_ADDR, edid, EDID_LENGTH); if (ret) { kfree(edid); goto out; } ptn_bridge->edid = (struct edid *)edid; drm_mode_connector_update_edid_property(connector, ptn_bridge->edid); num_modes = drm_add_edid_modes(connector, ptn_bridge->edid); out: if (power_off) ptn3460_disable(&ptn_bridge->bridge); return num_modes; } static const struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = { .get_modes = ptn3460_get_modes, }; static const struct drm_connector_funcs ptn3460_connector_funcs = { .dpms = drm_atomic_helper_connector_dpms, .fill_modes = drm_helper_probe_single_connector_modes, .destroy = drm_connector_cleanup, .reset = drm_atomic_helper_connector_reset, .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, }; static int ptn3460_bridge_attach(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge); int ret; if (!bridge->encoder) { DRM_ERROR("Parent encoder object not found"); return -ENODEV; } ptn_bridge->connector.polled = DRM_CONNECTOR_POLL_HPD; ret = drm_connector_init(bridge->dev, &ptn_bridge->connector, &ptn3460_connector_funcs, DRM_MODE_CONNECTOR_LVDS); if (ret) { DRM_ERROR("Failed to initialize connector with drm\n"); return ret; } drm_connector_helper_add(&ptn_bridge->connector, &ptn3460_connector_helper_funcs); drm_connector_register(&ptn_bridge->connector); drm_mode_connector_attach_encoder(&ptn_bridge->connector, bridge->encoder); if (ptn_bridge->panel) drm_panel_attach(ptn_bridge->panel, &ptn_bridge->connector); drm_helper_hpd_irq_event(ptn_bridge->connector.dev); return ret; } static const struct drm_bridge_funcs ptn3460_bridge_funcs = { .pre_enable = ptn3460_pre_enable, .enable = ptn3460_enable, .disable = ptn3460_disable, .post_disable = ptn3460_post_disable, .attach = ptn3460_bridge_attach, }; static int ptn3460_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; struct ptn3460_bridge *ptn_bridge; int ret; ptn_bridge = devm_kzalloc(dev, sizeof(*ptn_bridge), GFP_KERNEL); if (!ptn_bridge) { return -ENOMEM; } ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &ptn_bridge->panel, NULL); if (ret) return ret; ptn_bridge->client = client; ptn_bridge->gpio_pd_n = devm_gpiod_get(&client->dev, "powerdown", GPIOD_OUT_HIGH); if (IS_ERR(ptn_bridge->gpio_pd_n)) { ret = PTR_ERR(ptn_bridge->gpio_pd_n); dev_err(dev, "cannot get gpio_pd_n %d\n", ret); return ret; } /* * Request the reset pin low to avoid the bridge being * initialized prematurely */ ptn_bridge->gpio_rst_n = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW); if (IS_ERR(ptn_bridge->gpio_rst_n)) { ret = PTR_ERR(ptn_bridge->gpio_rst_n); DRM_ERROR("cannot get gpio_rst_n %d\n", ret); return ret; } ret = of_property_read_u32(dev->of_node, "edid-emulation", &ptn_bridge->edid_emulation); if (ret) { dev_err(dev, "Can't read EDID emulation value\n"); return ret; } ptn_bridge->bridge.funcs = &ptn3460_bridge_funcs; ptn_bridge->bridge.of_node = dev->of_node; drm_bridge_add(&ptn_bridge->bridge); i2c_set_clientdata(client, ptn_bridge); return 0; } static int ptn3460_remove(struct i2c_client *client) { struct ptn3460_bridge *ptn_bridge = i2c_get_clientdata(client); drm_bridge_remove(&ptn_bridge->bridge); return 0; } static const struct i2c_device_id ptn3460_i2c_table[] = { {"ptn3460", 0}, {}, }; MODULE_DEVICE_TABLE(i2c, ptn3460_i2c_table); static const struct of_device_id ptn3460_match[] = { { .compatible = "nxp,ptn3460" }, {}, }; MODULE_DEVICE_TABLE(of, ptn3460_match); static struct i2c_driver ptn3460_driver = { .id_table = ptn3460_i2c_table, .probe = ptn3460_probe, .remove = ptn3460_remove, .driver = { .name = "nxp,ptn3460", .of_match_table = ptn3460_match, }, }; module_i2c_driver(ptn3460_driver); MODULE_AUTHOR("Sean Paul "); MODULE_DESCRIPTION("NXP ptn3460 eDP-LVDS converter driver"); MODULE_LICENSE("GPL v2");