| /* |
| * 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_of.h> |
| #include <drm/drm_panel.h> |
| |
| #include "drm_crtc.h" |
| #include "drm_crtc_helper.h" |
| #include "drm_atomic_helper.h" |
| #include "drm_edid.h" |
| #include "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_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; |
| ret = drm_bridge_add(&ptn_bridge->bridge); |
| if (ret) { |
| DRM_ERROR("Failed to add bridge\n"); |
| return ret; |
| } |
| |
| 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 <seanpaul@chromium.org>"); |
| MODULE_DESCRIPTION("NXP ptn3460 eDP-LVDS converter driver"); |
| MODULE_LICENSE("GPL v2"); |