/* * 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/module.h> #include <linux/of.h> #include <linux/of_gpio.h> #include <linux/i2c.h> #include <linux/gpio.h> #include <linux/delay.h> #include "drmP.h" #include "drm_edid.h" #include "drm_crtc.h" #include "drm_crtc_helper.h" #include "bridge/ptn3460.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_encoder *encoder; struct drm_bridge *bridge; struct edid *edid; int gpio_pd_n; int gpio_rst_n; u32 edid_emulation; bool enabled; }; 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->driver_private; int ret; if (ptn_bridge->enabled) return; if (gpio_is_valid(ptn_bridge->gpio_pd_n)) gpio_set_value(ptn_bridge->gpio_pd_n, 1); if (gpio_is_valid(ptn_bridge->gpio_rst_n)) { gpio_set_value(ptn_bridge->gpio_rst_n, 0); udelay(10); gpio_set_value(ptn_bridge->gpio_rst_n, 1); } /* * 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) { } static void ptn3460_disable(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge->driver_private; if (!ptn_bridge->enabled) return; ptn_bridge->enabled = false; if (gpio_is_valid(ptn_bridge->gpio_rst_n)) gpio_set_value(ptn_bridge->gpio_rst_n, 1); if (gpio_is_valid(ptn_bridge->gpio_pd_n)) gpio_set_value(ptn_bridge->gpio_pd_n, 0); } static void ptn3460_post_disable(struct drm_bridge *bridge) { } void ptn3460_bridge_destroy(struct drm_bridge *bridge) { struct ptn3460_bridge *ptn_bridge = bridge->driver_private; drm_bridge_cleanup(bridge); if (gpio_is_valid(ptn_bridge->gpio_pd_n)) gpio_free(ptn_bridge->gpio_pd_n); if (gpio_is_valid(ptn_bridge->gpio_rst_n)) gpio_free(ptn_bridge->gpio_rst_n); /* Nothing else to free, we've got devm allocated memory */ } struct drm_bridge_funcs ptn3460_bridge_funcs = { .pre_enable = ptn3460_pre_enable, .enable = ptn3460_enable, .disable = ptn3460_disable, .post_disable = ptn3460_post_disable, .destroy = ptn3460_bridge_destroy, }; int ptn3460_get_modes(struct drm_connector *connector) { struct ptn3460_bridge *ptn_bridge; u8 *edid; int ret, num_modes; bool power_off; ptn_bridge = container_of(connector, struct ptn3460_bridge, 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); num_modes = 0; 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 int ptn3460_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) { return MODE_OK; } struct drm_encoder *ptn3460_best_encoder(struct drm_connector *connector) { struct ptn3460_bridge *ptn_bridge; ptn_bridge = container_of(connector, struct ptn3460_bridge, connector); return ptn_bridge->encoder; } struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = { .get_modes = ptn3460_get_modes, .mode_valid = ptn3460_mode_valid, .best_encoder = ptn3460_best_encoder, }; enum drm_connector_status ptn3460_detect(struct drm_connector *connector, bool force) { return connector_status_connected; } void ptn3460_connector_destroy(struct drm_connector *connector) { drm_connector_cleanup(connector); } struct drm_connector_funcs ptn3460_connector_funcs = { .dpms = drm_helper_connector_dpms, .fill_modes = drm_helper_probe_single_connector_modes, .detect = ptn3460_detect, .destroy = ptn3460_connector_destroy, }; int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder, struct i2c_client *client, struct device_node *node) { int ret; struct drm_bridge *bridge; struct ptn3460_bridge *ptn_bridge; bridge = devm_kzalloc(dev->dev, sizeof(*bridge), GFP_KERNEL); if (!bridge) { DRM_ERROR("Failed to allocate drm bridge\n"); return -ENOMEM; } ptn_bridge = devm_kzalloc(dev->dev, sizeof(*ptn_bridge), GFP_KERNEL); if (!ptn_bridge) { DRM_ERROR("Failed to allocate ptn bridge\n"); return -ENOMEM; } ptn_bridge->client = client; ptn_bridge->encoder = encoder; ptn_bridge->bridge = bridge; ptn_bridge->gpio_pd_n = of_get_named_gpio(node, "powerdown-gpio", 0); if (gpio_is_valid(ptn_bridge->gpio_pd_n)) { ret = gpio_request_one(ptn_bridge->gpio_pd_n, GPIOF_OUT_INIT_HIGH, "PTN3460_PD_N"); if (ret) { DRM_ERROR("Request powerdown-gpio failed (%d)\n", ret); return ret; } } ptn_bridge->gpio_rst_n = of_get_named_gpio(node, "reset-gpio", 0); if (gpio_is_valid(ptn_bridge->gpio_rst_n)) { /* * Request the reset pin low to avoid the bridge being * initialized prematurely */ ret = gpio_request_one(ptn_bridge->gpio_rst_n, GPIOF_OUT_INIT_LOW, "PTN3460_RST_N"); if (ret) { DRM_ERROR("Request reset-gpio failed (%d)\n", ret); gpio_free(ptn_bridge->gpio_pd_n); return ret; } } ret = of_property_read_u32(node, "edid-emulation", &ptn_bridge->edid_emulation); if (ret) { DRM_ERROR("Can't read edid emulation value\n"); goto err; } ret = drm_bridge_init(dev, bridge, &ptn3460_bridge_funcs); if (ret) { DRM_ERROR("Failed to initialize bridge with drm\n"); goto err; } bridge->driver_private = ptn_bridge; encoder->bridge = bridge; ret = drm_connector_init(dev, &ptn_bridge->connector, &ptn3460_connector_funcs, DRM_MODE_CONNECTOR_LVDS); if (ret) { DRM_ERROR("Failed to initialize connector with drm\n"); goto err; } drm_connector_helper_add(&ptn_bridge->connector, &ptn3460_connector_helper_funcs); drm_sysfs_connector_add(&ptn_bridge->connector); drm_mode_connector_attach_encoder(&ptn_bridge->connector, encoder); return 0; err: if (gpio_is_valid(ptn_bridge->gpio_pd_n)) gpio_free(ptn_bridge->gpio_pd_n); if (gpio_is_valid(ptn_bridge->gpio_rst_n)) gpio_free(ptn_bridge->gpio_rst_n); return ret; }