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/*
* Copyright (C) 2016 Texas Instruments
* Author: Jyri Sarha <jsarha@ti.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
*/
#include <linux/delay.h>
#include <linux/fwnode.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
#define HOTPLUG_DEBOUNCE_MS 1100
struct tfp410 {
struct drm_bridge bridge;
struct drm_connector connector;
unsigned int connector_type;
u32 bus_format;
struct i2c_adapter *ddc;
struct gpio_desc *hpd;
int hpd_irq;
struct delayed_work hpd_work;
struct gpio_desc *powerdown;
struct drm_bridge_timings timings;
struct device *dev;
};
static inline struct tfp410 *
drm_bridge_to_tfp410(struct drm_bridge *bridge)
{
return container_of(bridge, struct tfp410, bridge);
}
static inline struct tfp410 *
drm_connector_to_tfp410(struct drm_connector *connector)
{
return container_of(connector, struct tfp410, connector);
}
static int tfp410_get_modes(struct drm_connector *connector)
{
struct tfp410 *dvi = drm_connector_to_tfp410(connector);
struct edid *edid;
int ret;
if (!dvi->ddc)
goto fallback;
edid = drm_get_edid(connector, dvi->ddc);
if (!edid) {
DRM_INFO("EDID read failed. Fallback to standard modes\n");
goto fallback;
}
drm_connector_update_edid_property(connector, edid);
ret = drm_add_edid_modes(connector, edid);
kfree(edid);
return ret;
fallback:
/* No EDID, fallback on the XGA standard modes */
ret = drm_add_modes_noedid(connector, 1920, 1200);
/* And prefer a mode pretty much anything can handle */
drm_set_preferred_mode(connector, 1024, 768);
return ret;
}
static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
.get_modes = tfp410_get_modes,
};
static enum drm_connector_status
tfp410_connector_detect(struct drm_connector *connector, bool force)
{
struct tfp410 *dvi = drm_connector_to_tfp410(connector);
if (dvi->hpd) {
if (gpiod_get_value_cansleep(dvi->hpd))
return connector_status_connected;
else
return connector_status_disconnected;
}
if (dvi->ddc) {
if (drm_probe_ddc(dvi->ddc))
return connector_status_connected;
else
return connector_status_disconnected;
}
return connector_status_unknown;
}
static const struct drm_connector_funcs tfp410_con_funcs = {
.detect = tfp410_connector_detect,
.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 tfp410_attach(struct drm_bridge *bridge)
{
struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
int ret;
if (!bridge->encoder) {
dev_err(dvi->dev, "Missing encoder\n");
return -ENODEV;
}
if (dvi->hpd_irq >= 0)
dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
else
dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
drm_connector_helper_add(&dvi->connector,
&tfp410_con_helper_funcs);
ret = drm_connector_init(bridge->dev, &dvi->connector,
&tfp410_con_funcs, dvi->connector_type);
if (ret) {
dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret);
return ret;
}
drm_display_info_set_bus_formats(&dvi->connector.display_info,
&dvi->bus_format, 1);
drm_connector_attach_encoder(&dvi->connector,
bridge->encoder);
return 0;
}
static void tfp410_enable(struct drm_bridge *bridge)
{
struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
gpiod_set_value_cansleep(dvi->powerdown, 0);
}
static void tfp410_disable(struct drm_bridge *bridge)
{
struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
gpiod_set_value_cansleep(dvi->powerdown, 1);
}
static const struct drm_bridge_funcs tfp410_bridge_funcs = {
.attach = tfp410_attach,
.enable = tfp410_enable,
.disable = tfp410_disable,
};
static void tfp410_hpd_work_func(struct work_struct *work)
{
struct tfp410 *dvi;
dvi = container_of(work, struct tfp410, hpd_work.work);
if (dvi->bridge.dev)
drm_helper_hpd_irq_event(dvi->bridge.dev);
}
static irqreturn_t tfp410_hpd_irq_thread(int irq, void *arg)
{
struct tfp410 *dvi = arg;
mod_delayed_work(system_wq, &dvi->hpd_work,
msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS));
return IRQ_HANDLED;
}
static const struct drm_bridge_timings tfp410_default_timings = {
.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
| DRM_BUS_FLAG_DE_HIGH,
.setup_time_ps = 1200,
.hold_time_ps = 1300,
};
static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
{
struct drm_bridge_timings *timings = &dvi->timings;
struct device_node *ep;
u32 pclk_sample = 0;
u32 bus_width = 24;
s32 deskew = 0;
/* Start with defaults. */
*timings = tfp410_default_timings;
if (i2c)
/*
* In I2C mode timings are configured through the I2C interface.
* As the driver doesn't support I2C configuration yet, we just
* go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
*/
return 0;
/*
* In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
* and EDGE pins. They are specified in DT through endpoint properties
* and vendor-specific properties.
*/
ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
if (!ep)
return -EINVAL;
/* Get the sampling edge from the endpoint. */
of_property_read_u32(ep, "pclk-sample", &pclk_sample);
of_property_read_u32(ep, "bus-width", &bus_width);
of_node_put(ep);
timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
switch (pclk_sample) {
case 0:
timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
| DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
break;
case 1:
timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
| DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
break;
default:
return -EINVAL;
}
switch (bus_width) {
case 12:
dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
break;
case 24:
dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
break;
default:
return -EINVAL;
}
/* Get the setup and hold time from vendor-specific properties. */
of_property_read_u32(dvi->dev->of_node, "ti,deskew", (u32 *)&deskew);
if (deskew < -4 || deskew > 3)
return -EINVAL;
timings->setup_time_ps = min(0, 1200 - 350 * deskew);
timings->hold_time_ps = min(0, 1300 + 350 * deskew);
return 0;
}
static int tfp410_get_connector_properties(struct tfp410 *dvi)
{
struct device_node *connector_node, *ddc_phandle;
int ret = 0;
/* port@1 is the connector node */
connector_node = of_graph_get_remote_node(dvi->dev->of_node, 1, -1);
if (!connector_node)
return -ENODEV;
if (of_device_is_compatible(connector_node, "hdmi-connector"))
dvi->connector_type = DRM_MODE_CONNECTOR_HDMIA;
else
dvi->connector_type = DRM_MODE_CONNECTOR_DVID;
dvi->hpd = fwnode_get_named_gpiod(&connector_node->fwnode,
"hpd-gpios", 0, GPIOD_IN, "hpd");
if (IS_ERR(dvi->hpd)) {
ret = PTR_ERR(dvi->hpd);
dvi->hpd = NULL;
if (ret == -ENOENT)
ret = 0;
else
goto fail;
}
ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0);
if (!ddc_phandle)
goto fail;
dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle);
if (dvi->ddc)
dev_info(dvi->dev, "Connector's ddc i2c bus found\n");
else
ret = -EPROBE_DEFER;
of_node_put(ddc_phandle);
fail:
of_node_put(connector_node);
return ret;
}
static int tfp410_init(struct device *dev, bool i2c)
{
struct tfp410 *dvi;
int ret;
if (!dev->of_node) {
dev_err(dev, "device-tree data is missing\n");
return -ENXIO;
}
dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
if (!dvi)
return -ENOMEM;
dev_set_drvdata(dev, dvi);
dvi->bridge.funcs = &tfp410_bridge_funcs;
dvi->bridge.of_node = dev->of_node;
dvi->bridge.timings = &dvi->timings;
dvi->dev = dev;
ret = tfp410_parse_timings(dvi, i2c);
if (ret)
goto fail;
ret = tfp410_get_connector_properties(dvi);
if (ret)
goto fail;
dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
GPIOD_OUT_HIGH);
if (IS_ERR(dvi->powerdown)) {
dev_err(dev, "failed to parse powerdown gpio\n");
return PTR_ERR(dvi->powerdown);
}
if (dvi->hpd)
dvi->hpd_irq = gpiod_to_irq(dvi->hpd);
else
dvi->hpd_irq = -ENXIO;
if (dvi->hpd_irq >= 0) {
INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
ret = devm_request_threaded_irq(dev, dvi->hpd_irq,
NULL, tfp410_hpd_irq_thread, IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
"hdmi-hpd", dvi);
if (ret) {
DRM_ERROR("failed to register hpd interrupt\n");
goto fail;
}
}
drm_bridge_add(&dvi->bridge);
return 0;
fail:
i2c_put_adapter(dvi->ddc);
if (dvi->hpd)
gpiod_put(dvi->hpd);
return ret;
}
static int tfp410_fini(struct device *dev)
{
struct tfp410 *dvi = dev_get_drvdata(dev);
if (dvi->hpd_irq >= 0)
cancel_delayed_work_sync(&dvi->hpd_work);
drm_bridge_remove(&dvi->bridge);
if (dvi->ddc)
i2c_put_adapter(dvi->ddc);
if (dvi->hpd)
gpiod_put(dvi->hpd);
return 0;
}
static int tfp410_probe(struct platform_device *pdev)
{
return tfp410_init(&pdev->dev, false);
}
static int tfp410_remove(struct platform_device *pdev)
{
return tfp410_fini(&pdev->dev);
}
static const struct of_device_id tfp410_match[] = {
{ .compatible = "ti,tfp410" },
{},
};
MODULE_DEVICE_TABLE(of, tfp410_match);
static struct platform_driver tfp410_platform_driver = {
.probe = tfp410_probe,
.remove = tfp410_remove,
.driver = {
.name = "tfp410-bridge",
.of_match_table = tfp410_match,
},
};
#if IS_ENABLED(CONFIG_I2C)
/* There is currently no i2c functionality. */
static int tfp410_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int reg;
if (!client->dev.of_node ||
of_property_read_u32(client->dev.of_node, "reg", ®)) {
dev_err(&client->dev,
"Can't get i2c reg property from device-tree\n");
return -ENXIO;
}
return tfp410_init(&client->dev, true);
}
static int tfp410_i2c_remove(struct i2c_client *client)
{
return tfp410_fini(&client->dev);
}
static const struct i2c_device_id tfp410_i2c_ids[] = {
{ "tfp410", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
static struct i2c_driver tfp410_i2c_driver = {
.driver = {
.name = "tfp410",
.of_match_table = of_match_ptr(tfp410_match),
},
.id_table = tfp410_i2c_ids,
.probe = tfp410_i2c_probe,
.remove = tfp410_i2c_remove,
};
#endif /* IS_ENABLED(CONFIG_I2C) */
static struct {
uint i2c:1;
uint platform:1;
} tfp410_registered_driver;
static int __init tfp410_module_init(void)
{
int ret;
#if IS_ENABLED(CONFIG_I2C)
ret = i2c_add_driver(&tfp410_i2c_driver);
if (ret)
pr_err("%s: registering i2c driver failed: %d",
__func__, ret);
else
tfp410_registered_driver.i2c = 1;
#endif
ret = platform_driver_register(&tfp410_platform_driver);
if (ret)
pr_err("%s: registering platform driver failed: %d",
__func__, ret);
else
tfp410_registered_driver.platform = 1;
if (tfp410_registered_driver.i2c ||
tfp410_registered_driver.platform)
return 0;
return ret;
}
module_init(tfp410_module_init);
static void __exit tfp410_module_exit(void)
{
#if IS_ENABLED(CONFIG_I2C)
if (tfp410_registered_driver.i2c)
i2c_del_driver(&tfp410_i2c_driver);
#endif
if (tfp410_registered_driver.platform)
platform_driver_unregister(&tfp410_platform_driver);
}
module_exit(tfp410_module_exit);
MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
MODULE_LICENSE("GPL");
|