--- /dev/null
+/*
+ * 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/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_graph.h>
+
+#include <drm/drm_panel.h>
+
+#include "bridge/ptn3460.h"
+
+#include "drm_crtc.h"
+#include "drm_crtc_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 struct drm_encoder *ptn3460_best_encoder(struct drm_connector *connector)
+{
+ struct ptn3460_bridge *ptn_bridge = connector_to_ptn3460(connector);
+
+ return ptn_bridge->bridge.encoder;
+}
+
+static struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = {
+ .get_modes = ptn3460_get_modes,
+ .best_encoder = ptn3460_best_encoder,
+};
+
+static enum drm_connector_status ptn3460_detect(struct drm_connector *connector,
+ bool force)
+{
+ return connector_status_connected;
+}
+
+static void ptn3460_connector_destroy(struct drm_connector *connector)
+{
+ drm_connector_cleanup(connector);
+}
+
+static 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,
+};
+
+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 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;
+ struct device_node *endpoint, *panel_node;
+ int ret;
+
+ ptn_bridge = devm_kzalloc(dev, sizeof(*ptn_bridge), GFP_KERNEL);
+ if (!ptn_bridge) {
+ return -ENOMEM;
+ }
+
+ endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+ if (endpoint) {
+ panel_node = of_graph_get_remote_port_parent(endpoint);
+ if (panel_node) {
+ ptn_bridge->panel = of_drm_find_panel(panel_node);
+ of_node_put(panel_node);
+ if (!ptn_bridge->panel)
+ return -EPROBE_DEFER;
+ }
+ }
+
+ ptn_bridge->client = client;
+
+ ptn_bridge->gpio_pd_n = devm_gpiod_get(&client->dev, "powerdown");
+ 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;
+ }
+
+ ret = gpiod_direction_output(ptn_bridge->gpio_pd_n, 1);
+ if (ret) {
+ DRM_ERROR("cannot configure gpio_pd_n\n");
+ return ret;
+ }
+
+ ptn_bridge->gpio_rst_n = devm_gpiod_get(&client->dev, "reset");
+ 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;
+ }
+ /*
+ * Request the reset pin low to avoid the bridge being
+ * initialized prematurely
+ */
+ ret = gpiod_direction_output(ptn_bridge->gpio_rst_n, 0);
+ if (ret) {
+ DRM_ERROR("cannot configure gpio_rst_n\n");
+ 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[] = {
+ {"nxp,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",
+ .owner = THIS_MODULE,
+ .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");
Code Review / kvmfornfv.git / blobdiff