|  | /* | 
|  | * 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 <linux/delay.h> | 
|  | #include <linux/gpio.h> | 
|  | #include <linux/gpio/consumer.h> | 
|  | #include <linux/i2c.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/of.h> | 
|  | #include <linux/of_gpio.h> | 
|  | #include <drm/drm_atomic_helper.h> | 
|  | #include <drm/drm_crtc.h> | 
|  | #include <drm/drm_crtc_helper.h> | 
|  | #include <drm/drm_edid.h> | 
|  | #include <drm/drm_of.h> | 
|  | #include <drm/drm_panel.h> | 
|  | #include <drm/drmP.h> | 
|  |  | 
|  | #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_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 = { | 
|  | .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_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 <[email protected]>"); | 
|  | MODULE_DESCRIPTION("NXP ptn3460 eDP-LVDS converter driver"); | 
|  | MODULE_LICENSE("GPL v2"); |