#include <linux/device.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/media-bus-format.h>
#include <linux/regmap.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_of.h>
#include <video/videomode.h>
#define I2C_MAIN 0
#define I2C_ADDR_MAIN 0x48
#define I2C_CEC_DSI 1
#define I2C_ADDR_CEC_DSI 0x49
#define I2C_MAX_IDX 2
struct lt8912 {
struct device *dev;
struct drm_bridge bridge;
struct drm_connector connector;
struct i2c_client *i2c_client[I2C_MAX_IDX];
struct regmap *regmap[I2C_MAX_IDX];
struct device_node *host_node;
struct drm_bridge *hdmi_port;
struct mipi_dsi_device *dsi;
struct gpio_desc *gp_reset;
struct videomode mode;
u8 data_lanes;
bool is_power_on;
bool is_attached;
};
static int lt8912_write_init_config(struct lt8912 *lt)
{
const struct reg_sequence seq[] = {
{0x08, 0xff},
{0x09, 0xff},
{0x0a, 0xff},
{0x0b, 0x7c},
{0x0c, 0xff},
{0x42, 0x04},
{0x31, 0xb1},
{0x32, 0xb1},
{0x33, 0x0e},
{0x37, 0x00},
{0x38, 0x22},
{0x60, 0x82},
{0x39, 0x45},
{0x3a, 0x00},
{0x3b, 0x00},
{0x44, 0x31},
{0x55, 0x44},
{0x57, 0x01},
{0x5a, 0x02},
{0x3e, 0xd6},
{0x3f, 0xd4},
{0x41, 0x3c},
{0xB2, 0x00},
};
return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq));
}
static int lt8912_write_mipi_basic_config(struct lt8912 *lt)
{
const struct reg_sequence seq[] = {
{0x12, 0x04},
{0x14, 0x00},
{0x15, 0x00},
{0x1a, 0x03},
{0x1b, 0x03},
};
return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
};
static int lt8912_write_dds_config(struct lt8912 *lt)
{
const struct reg_sequence seq[] = {
{0x4e, 0xff},
{0x4f, 0x56},
{0x50, 0x69},
{0x51, 0x80},
{0x1f, 0x5e},
{0x20, 0x01},
{0x21, 0x2c},
{0x22, 0x01},
{0x23, 0xfa},
{0x24, 0x00},
{0x25, 0xc8},
{0x26, 0x00},
{0x27, 0x5e},
{0x28, 0x01},
{0x29, 0x2c},
{0x2a, 0x01},
{0x2b, 0xfa},
{0x2c, 0x00},
{0x2d, 0xc8},
{0x2e, 0x00},
{0x42, 0x64},
{0x43, 0x00},
{0x44, 0x04},
{0x45, 0x00},
{0x46, 0x59},
{0x47, 0x00},
{0x48, 0xf2},
{0x49, 0x06},
{0x4a, 0x00},
{0x4b, 0x72},
{0x4c, 0x45},
{0x4d, 0x00},
{0x52, 0x08},
{0x53, 0x00},
{0x54, 0xb2},
{0x55, 0x00},
{0x56, 0xe4},
{0x57, 0x0d},
{0x58, 0x00},
{0x59, 0xe4},
{0x5a, 0x8a},
{0x5b, 0x00},
{0x5c, 0x34},
{0x1e, 0x4f},
{0x51, 0x00},
};
return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
}
static int lt8912_write_rxlogicres_config(struct lt8912 *lt)
{
int ret;
ret = regmap_write(lt->regmap[I2C_MAIN], 0x03, 0x7f);
usleep_range(10000, 20000);
ret |= regmap_write(lt->regmap[I2C_MAIN], 0x03, 0xff);
return ret;
};
static int lt8912_write_lvds_config(struct lt8912 *lt)
{
const struct reg_sequence seq[] = {
{0x44, 0x30},
{0x51, 0x05},
{0x50, 0x24},
{0x51, 0x2d},
{0x52, 0x04},
{0x69, 0x0e},
{0x69, 0x8e},
{0x6a, 0x00},
{0x6c, 0xb8},
{0x6b, 0x51},
{0x04, 0xfb},
{0x04, 0xff},
{0x7f, 0x00},
{0xa8, 0x13},
{0x02, 0xf7},
{0x02, 0xff},
{0x03, 0xcf},
{0x03, 0xff},
};
return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq));
};
static inline struct lt8912 *bridge_to_lt8912(struct drm_bridge *b)
{
return container_of(b, struct lt8912, bridge);
}
static inline struct lt8912 *connector_to_lt8912(struct drm_connector *c)
{
return container_of(c, struct lt8912, connector);
}
static const struct regmap_config lt8912_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0xff,
};
static int lt8912_init_i2c(struct lt8912 *lt, struct i2c_client *client)
{
unsigned int i;
struct i2c_board_info info[] = {
{ I2C_BOARD_INFO("lt8912p0", I2C_ADDR_MAIN), },
{ I2C_BOARD_INFO("lt8912p1", I2C_ADDR_CEC_DSI), },
};
if (!lt)
return -ENODEV;
for (i = 0; i < ARRAY_SIZE(info); i++) {
if (i > 0) {
lt->i2c_client[i] = i2c_new_dummy_device(client->adapter,
info[i].addr);
if (IS_ERR(lt->i2c_client[i]))
return PTR_ERR(lt->i2c_client[i]);
}
lt->regmap[i] = devm_regmap_init_i2c(lt->i2c_client[i],
<8912_regmap_config);
if (IS_ERR(lt->regmap[i]))
return PTR_ERR(lt->regmap[i]);
}
return 0;
}
static int lt8912_free_i2c(struct lt8912 *lt)
{
unsigned int i;
for (i = 1; i < I2C_MAX_IDX; i++)
i2c_unregister_device(lt->i2c_client[i]);
return 0;
}
static int lt8912_hard_power_on(struct lt8912 *lt)
{
gpiod_set_value_cansleep(lt->gp_reset, 0);
msleep(20);
return 0;
}
static void lt8912_hard_power_off(struct lt8912 *lt)
{
gpiod_set_value_cansleep(lt->gp_reset, 1);
msleep(20);
lt->is_power_on = false;
}
static int lt8912_video_setup(struct lt8912 *lt)
{
u32 hactive, h_total, hpw, hfp, hbp;
u32 vactive, v_total, vpw, vfp, vbp;
u8 settle = 0x08;
int ret, hsync_activehigh, vsync_activehigh;
if (!lt)
return -EINVAL;
hactive = lt->mode.hactive;
hfp = lt->mode.hfront_porch;
hpw = lt->mode.hsync_len;
hbp = lt->mode.hback_porch;
h_total = hactive + hfp + hpw + hbp;
hsync_activehigh = lt->mode.flags & DISPLAY_FLAGS_HSYNC_HIGH;
vactive = lt->mode.vactive;
vfp = lt->mode.vfront_porch;
vpw = lt->mode.vsync_len;
vbp = lt->mode.vback_porch;
v_total = vactive + vfp + vpw + vbp;
vsync_activehigh = lt->mode.flags & DISPLAY_FLAGS_VSYNC_HIGH;
if (vactive <= 600)
settle = 0x04;
else if (vactive == 1080)
settle = 0x0a;
ret = regmap_write(lt->regmap[I2C_CEC_DSI], 0x10, 0x01);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x11, settle);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x18, hpw);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x19, vpw);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1c, hactive & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1d, hactive >> 8);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x2f, 0x0c);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x34, h_total & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x35, h_total >> 8);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x36, v_total & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x37, v_total >> 8);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x38, vbp & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x39, vbp >> 8);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3a, vfp & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3b, vfp >> 8);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3c, hbp & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3d, hbp >> 8);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3e, hfp & 0xff);
ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3f, hfp >> 8);
ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xab, BIT(0),
vsync_activehigh ? BIT(0) : 0);
ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xab, BIT(1),
hsync_activehigh ? BIT(1) : 0);
ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xb2, BIT(0),
lt->connector.display_info.is_hdmi ? BIT(0) : 0);
return ret;
}
static int lt8912_soft_power_on(struct lt8912 *lt)
{
if (!lt->is_power_on) {
u32 lanes = lt->data_lanes;
lt8912_write_init_config(lt);
regmap_write(lt->regmap[I2C_CEC_DSI], 0x13, lanes & 3);
lt8912_write_mipi_basic_config(lt);
lt->is_power_on = true;
}
return 0;
}
static int lt8912_video_on(struct lt8912 *lt)
{
int ret;
ret = lt8912_video_setup(lt);
if (ret < 0)
goto end;
ret = lt8912_write_dds_config(lt);
if (ret < 0)
goto end;
ret = lt8912_write_rxlogicres_config(lt);
if (ret < 0)
goto end;
ret = lt8912_write_lvds_config(lt);
if (ret < 0)
goto end;
end:
return ret;
}
static enum drm_connector_status lt8912_check_cable_status(struct lt8912 *lt)
{
int ret;
unsigned int reg_val;
ret = regmap_read(lt->regmap[I2C_MAIN], 0xC1, ®_val);
if (ret)
return connector_status_unknown;
if (reg_val & BIT(7))
return connector_status_connected;
return connector_status_disconnected;
}
static enum drm_connector_status
lt8912_connector_detect(struct drm_connector *connector, bool force)
{
struct lt8912 *lt = connector_to_lt8912(connector);
if (lt->hdmi_port->ops & DRM_BRIDGE_OP_DETECT)
return drm_bridge_detect(lt->hdmi_port);
return lt8912_check_cable_status(lt);
}
static const struct drm_connector_funcs lt8912_connector_funcs = {
.detect = lt8912_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 enum drm_mode_status
lt8912_connector_mode_valid(struct drm_connector *connector,
struct drm_display_mode *mode)
{
if (mode->clock > 150000)
return MODE_CLOCK_HIGH;
if (mode->hdisplay > 1920)
return MODE_BAD_HVALUE;
if (mode->vdisplay > 1080)
return MODE_BAD_VVALUE;
return MODE_OK;
}
static int lt8912_connector_get_modes(struct drm_connector *connector)
{
struct edid *edid;
int ret = -1;
int num = 0;
struct lt8912 *lt = connector_to_lt8912(connector);
u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
edid = drm_bridge_get_edid(lt->hdmi_port, connector);
if (edid) {
drm_connector_update_edid_property(connector, edid);
num = drm_add_edid_modes(connector, edid);
} else {
return ret;
}
ret = drm_display_info_set_bus_formats(&connector->display_info,
&bus_format, 1);
if (ret)
num = ret;
kfree(edid);
return num;
}
static const struct drm_connector_helper_funcs lt8912_connector_helper_funcs = {
.get_modes = lt8912_connector_get_modes,
.mode_valid = lt8912_connector_mode_valid,
};
static void lt8912_bridge_mode_set(struct drm_bridge *bridge,
const struct drm_display_mode *mode,
const struct drm_display_mode *adj)
{
struct lt8912 *lt = bridge_to_lt8912(bridge);
drm_display_mode_to_videomode(adj, <->mode);
}
static void lt8912_bridge_enable(struct drm_bridge *bridge)
{
struct lt8912 *lt = bridge_to_lt8912(bridge);
lt8912_video_on(lt);
}
static int lt8912_attach_dsi(struct lt8912 *lt)
{
struct device *dev = lt->dev;
struct mipi_dsi_host *host;
struct mipi_dsi_device *dsi;
int ret = -1;
const struct mipi_dsi_device_info info = { .type = "lt8912",
.channel = 0,
.node = NULL,
};
host = of_find_mipi_dsi_host_by_node(lt->host_node);
if (!host) {
dev_err(dev, "failed to find dsi host\n");
return -EPROBE_DEFER;
}
dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
if (IS_ERR(dsi)) {
ret = PTR_ERR(dsi);
dev_err(dev, "failed to create dsi device (%d)\n", ret);
return ret;
}
lt->dsi = dsi;
dsi->lanes = lt->data_lanes;
dsi->format = MIPI_DSI_FMT_RGB888;
dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
MIPI_DSI_MODE_LPM |
MIPI_DSI_MODE_NO_EOT_PACKET;
ret = devm_mipi_dsi_attach(dev, dsi);
if (ret < 0) {
dev_err(dev, "failed to attach dsi to host\n");
return ret;
}
return 0;
}
static void lt8912_bridge_hpd_cb(void *data, enum drm_connector_status status)
{
struct lt8912 *lt = data;
if (lt->bridge.dev)
drm_helper_hpd_irq_event(lt->bridge.dev);
}
static int lt8912_bridge_connector_init(struct drm_bridge *bridge)
{
int ret;
struct lt8912 *lt = bridge_to_lt8912(bridge);
struct drm_connector *connector = <->connector;
if (lt->hdmi_port->ops & DRM_BRIDGE_OP_HPD) {
drm_bridge_hpd_enable(lt->hdmi_port, lt8912_bridge_hpd_cb, lt);
connector->polled = DRM_CONNECTOR_POLL_HPD;
} else {
connector->polled = DRM_CONNECTOR_POLL_CONNECT |
DRM_CONNECTOR_POLL_DISCONNECT;
}
ret = drm_connector_init(bridge->dev, connector,
<8912_connector_funcs,
lt->hdmi_port->type);
if (ret)
goto exit;
drm_connector_helper_add(connector, <8912_connector_helper_funcs);
connector->dpms = DRM_MODE_DPMS_OFF;
drm_connector_attach_encoder(connector, bridge->encoder);
exit:
return ret;
}
static int lt8912_bridge_attach(struct drm_bridge *bridge,
enum drm_bridge_attach_flags flags)
{
struct lt8912 *lt = bridge_to_lt8912(bridge);
int ret;
if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
ret = lt8912_bridge_connector_init(bridge);
if (ret) {
dev_err(lt->dev, "Failed to init bridge ! (%d)\n", ret);
return ret;
}
}
ret = lt8912_hard_power_on(lt);
if (ret)
return ret;
ret = lt8912_soft_power_on(lt);
if (ret)
goto error;
lt->is_attached = true;
return 0;
error:
lt8912_hard_power_off(lt);
return ret;
}
static void lt8912_bridge_detach(struct drm_bridge *bridge)
{
struct lt8912 *lt = bridge_to_lt8912(bridge);
if (lt->is_attached) {
lt8912_hard_power_off(lt);
if (lt->hdmi_port->ops & DRM_BRIDGE_OP_HPD)
drm_bridge_hpd_disable(lt->hdmi_port);
drm_connector_unregister(<->connector);
drm_connector_cleanup(<->connector);
}
}
static enum drm_connector_status
lt8912_bridge_detect(struct drm_bridge *bridge)
{
struct lt8912 *lt = bridge_to_lt8912(bridge);
if (lt->hdmi_port->ops & DRM_BRIDGE_OP_DETECT)
return drm_bridge_detect(lt->hdmi_port);
return lt8912_check_cable_status(lt);
}
static struct edid *lt8912_bridge_get_edid(struct drm_bridge *bridge,
struct drm_connector *connector)
{
struct lt8912 *lt = bridge_to_lt8912(bridge);
if (lt->hdmi_port->ops & DRM_BRIDGE_OP_EDID)
return drm_bridge_get_edid(lt->hdmi_port, connector);
dev_warn(lt->dev, "The connected bridge does not supports DRM_BRIDGE_OP_EDID\n");
return NULL;
}
static const struct drm_bridge_funcs lt8912_bridge_funcs = {
.attach = lt8912_bridge_attach,
.detach = lt8912_bridge_detach,
.mode_set = lt8912_bridge_mode_set,
.enable = lt8912_bridge_enable,
.detect = lt8912_bridge_detect,
.get_edid = lt8912_bridge_get_edid,
};
static int lt8912_parse_dt(struct lt8912 *lt)
{
struct gpio_desc *gp_reset;
struct device *dev = lt->dev;
int ret;
int data_lanes;
struct device_node *port_node;
gp_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(gp_reset)) {
ret = PTR_ERR(gp_reset);
if (ret != -EPROBE_DEFER)
dev_err(dev, "Failed to get reset gpio: %d\n", ret);
return ret;
}
lt->gp_reset = gp_reset;
data_lanes = drm_of_get_data_lanes_count_ep(dev->of_node, 0, -1, 1, 4);
if (data_lanes < 0) {
dev_err(lt->dev, "%s: Bad data-lanes property\n", __func__);
return data_lanes;
}
lt->data_lanes = data_lanes;
lt->host_node = of_graph_get_remote_node(dev->of_node, 0, -1);
if (!lt->host_node) {
dev_err(lt->dev, "%s: Failed to get remote port\n", __func__);
return -ENODEV;
}
port_node = of_graph_get_remote_node(dev->of_node, 1, -1);
if (!port_node) {
dev_err(lt->dev, "%s: Failed to get connector port\n", __func__);
ret = -ENODEV;
goto err_free_host_node;
}
lt->hdmi_port = of_drm_find_bridge(port_node);
if (!lt->hdmi_port) {
ret = -EPROBE_DEFER;
dev_err_probe(lt->dev, ret, "%s: Failed to get hdmi port\n", __func__);
goto err_free_host_node;
}
if (!of_device_is_compatible(port_node, "hdmi-connector")) {
dev_err(lt->dev, "%s: Failed to get hdmi port\n", __func__);
ret = -EINVAL;
goto err_free_host_node;
}
of_node_put(port_node);
return 0;
err_free_host_node:
of_node_put(port_node);
of_node_put(lt->host_node);
return ret;
}
static int lt8912_put_dt(struct lt8912 *lt)
{
of_node_put(lt->host_node);
return 0;
}
static int lt8912_probe(struct i2c_client *client)
{
static struct lt8912 *lt;
int ret = 0;
struct device *dev = &client->dev;
lt = devm_kzalloc(dev, sizeof(struct lt8912), GFP_KERNEL);
if (!lt)
return -ENOMEM;
lt->dev = dev;
lt->i2c_client[0] = client;
ret = lt8912_parse_dt(lt);
if (ret)
goto err_dt_parse;
ret = lt8912_init_i2c(lt, client);
if (ret)
goto err_i2c;
i2c_set_clientdata(client, lt);
lt->bridge.funcs = <8912_bridge_funcs;
lt->bridge.of_node = dev->of_node;
lt->bridge.ops = (DRM_BRIDGE_OP_EDID |
DRM_BRIDGE_OP_DETECT);
drm_bridge_add(<->bridge);
ret = lt8912_attach_dsi(lt);
if (ret)
goto err_attach;
return 0;
err_attach:
drm_bridge_remove(<->bridge);
lt8912_free_i2c(lt);
err_i2c:
lt8912_put_dt(lt);
err_dt_parse:
return ret;
}
static void lt8912_remove(struct i2c_client *client)
{
struct lt8912 *lt = i2c_get_clientdata(client);
lt8912_bridge_detach(<->bridge);
drm_bridge_remove(<->bridge);
lt8912_free_i2c(lt);
lt8912_put_dt(lt);
}
static const struct of_device_id lt8912_dt_match[] = {
{.compatible = "lontium,lt8912b"},
{}
};
MODULE_DEVICE_TABLE(of, lt8912_dt_match);
static const struct i2c_device_id lt8912_id[] = {
{"lt8912", 0},
{},
};
MODULE_DEVICE_TABLE(i2c, lt8912_id);
static struct i2c_driver lt8912_i2c_driver = {
.driver = {
.name = "lt8912",
.of_match_table = lt8912_dt_match,
},
.probe = lt8912_probe,
.remove = lt8912_remove,
.id_table = lt8912_id,
};
module_i2c_driver(lt8912_i2c_driver);
MODULE_AUTHOR("Adrien Grassein <adrien.grassein@gmail.com>");
MODULE_DESCRIPTION("lt8912 drm driver");
MODULE_LICENSE("GPL v2"