blob: 3e7e33cd3dfa46ec226b2fbf50bc925550d1c124 [file] [log] [blame]
/*
* Copyright (C) 2017 Sanechips Technology Co., Ltd.
* Copyright 2017 Linaro Ltd.
*
* 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/clk.h>
#include <linux/component.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drmP.h>
#include "zx_drm_drv.h"
#include "zx_vga_regs.h"
#include "zx_vou.h"
struct zx_vga_pwrctrl {
struct regmap *regmap;
u32 reg;
u32 mask;
};
struct zx_vga_i2c {
struct i2c_adapter adap;
struct mutex lock;
};
struct zx_vga {
struct drm_connector connector;
struct drm_encoder encoder;
struct zx_vga_i2c *ddc;
struct device *dev;
void __iomem *mmio;
struct clk *i2c_wclk;
struct zx_vga_pwrctrl pwrctrl;
struct completion complete;
bool connected;
};
#define to_zx_vga(x) container_of(x, struct zx_vga, x)
static void zx_vga_encoder_enable(struct drm_encoder *encoder)
{
struct zx_vga *vga = to_zx_vga(encoder);
struct zx_vga_pwrctrl *pwrctrl = &vga->pwrctrl;
/* Set bit to power up VGA DACs */
regmap_update_bits(pwrctrl->regmap, pwrctrl->reg, pwrctrl->mask,
pwrctrl->mask);
vou_inf_enable(VOU_VGA, encoder->crtc);
}
static void zx_vga_encoder_disable(struct drm_encoder *encoder)
{
struct zx_vga *vga = to_zx_vga(encoder);
struct zx_vga_pwrctrl *pwrctrl = &vga->pwrctrl;
vou_inf_disable(VOU_VGA, encoder->crtc);
/* Clear bit to power down VGA DACs */
regmap_update_bits(pwrctrl->regmap, pwrctrl->reg, pwrctrl->mask, 0);
}
static const struct drm_encoder_helper_funcs zx_vga_encoder_helper_funcs = {
.enable = zx_vga_encoder_enable,
.disable = zx_vga_encoder_disable,
};
static const struct drm_encoder_funcs zx_vga_encoder_funcs = {
.destroy = drm_encoder_cleanup,
};
static int zx_vga_connector_get_modes(struct drm_connector *connector)
{
struct zx_vga *vga = to_zx_vga(connector);
struct edid *edid;
int ret;
/*
* Clear both detection bits to switch I2C bus from device
* detecting to EDID reading.
*/
zx_writel(vga->mmio + VGA_AUTO_DETECT_SEL, 0);
edid = drm_get_edid(connector, &vga->ddc->adap);
if (!edid) {
/*
* If EDID reading fails, we set the device state into
* disconnected. Locking is not required here, since the
* VGA_AUTO_DETECT_SEL register write in irq handler cannot
* be triggered when both detection bits are cleared as above.
*/
zx_writel(vga->mmio + VGA_AUTO_DETECT_SEL,
VGA_DETECT_SEL_NO_DEVICE);
vga->connected = false;
return 0;
}
/*
* As edid reading succeeds, device must be connected, so we set
* up detection bit for unplug interrupt here.
*/
zx_writel(vga->mmio + VGA_AUTO_DETECT_SEL, VGA_DETECT_SEL_HAS_DEVICE);
drm_mode_connector_update_edid_property(connector, edid);
ret = drm_add_edid_modes(connector, edid);
kfree(edid);
return ret;
}
static enum drm_mode_status
zx_vga_connector_mode_valid(struct drm_connector *connector,
struct drm_display_mode *mode)
{
return MODE_OK;
}
static struct drm_connector_helper_funcs zx_vga_connector_helper_funcs = {
.get_modes = zx_vga_connector_get_modes,
.mode_valid = zx_vga_connector_mode_valid,
};
static enum drm_connector_status
zx_vga_connector_detect(struct drm_connector *connector, bool force)
{
struct zx_vga *vga = to_zx_vga(connector);
return vga->connected ? connector_status_connected :
connector_status_disconnected;
}
static const struct drm_connector_funcs zx_vga_connector_funcs = {
.fill_modes = drm_helper_probe_single_connector_modes,
.detect = zx_vga_connector_detect,
.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 zx_vga_register(struct drm_device *drm, struct zx_vga *vga)
{
struct drm_encoder *encoder = &vga->encoder;
struct drm_connector *connector = &vga->connector;
struct device *dev = vga->dev;
int ret;
encoder->possible_crtcs = VOU_CRTC_MASK;
ret = drm_encoder_init(drm, encoder, &zx_vga_encoder_funcs,
DRM_MODE_ENCODER_DAC, NULL);
if (ret) {
DRM_DEV_ERROR(dev, "failed to init encoder: %d\n", ret);
return ret;
};
drm_encoder_helper_add(encoder, &zx_vga_encoder_helper_funcs);
vga->connector.polled = DRM_CONNECTOR_POLL_HPD;
ret = drm_connector_init(drm, connector, &zx_vga_connector_funcs,
DRM_MODE_CONNECTOR_VGA);
if (ret) {
DRM_DEV_ERROR(dev, "failed to init connector: %d\n", ret);
goto clean_encoder;
};
drm_connector_helper_add(connector, &zx_vga_connector_helper_funcs);
ret = drm_mode_connector_attach_encoder(connector, encoder);
if (ret) {
DRM_DEV_ERROR(dev, "failed to attach encoder: %d\n", ret);
goto clean_connector;
};
return 0;
clean_connector:
drm_connector_cleanup(connector);
clean_encoder:
drm_encoder_cleanup(encoder);
return ret;
}
static int zx_vga_pwrctrl_init(struct zx_vga *vga)
{
struct zx_vga_pwrctrl *pwrctrl = &vga->pwrctrl;
struct device *dev = vga->dev;
struct of_phandle_args out_args;
struct regmap *regmap;
int ret;
ret = of_parse_phandle_with_fixed_args(dev->of_node,
"zte,vga-power-control", 2, 0, &out_args);
if (ret)
return ret;
regmap = syscon_node_to_regmap(out_args.np);
if (IS_ERR(regmap)) {
ret = PTR_ERR(regmap);
goto out;
}
pwrctrl->regmap = regmap;
pwrctrl->reg = out_args.args[0];
pwrctrl->mask = out_args.args[1];
out:
of_node_put(out_args.np);
return ret;
}
static int zx_vga_i2c_read(struct zx_vga *vga, struct i2c_msg *msg)
{
int len = msg->len;
u8 *buf = msg->buf;
u32 offset = 0;
int i;
reinit_completion(&vga->complete);
/* Select combo write */
zx_writel_mask(vga->mmio + VGA_CMD_CFG, VGA_CMD_COMBO, VGA_CMD_COMBO);
zx_writel_mask(vga->mmio + VGA_CMD_CFG, VGA_CMD_RW, 0);
while (len > 0) {
u32 cnt;
/* Clear RX FIFO */
zx_writel_mask(vga->mmio + VGA_RXF_CTRL, VGA_RX_FIFO_CLEAR,
VGA_RX_FIFO_CLEAR);
/* Data offset to read from */
zx_writel(vga->mmio + VGA_SUB_ADDR, offset);
/* Kick off the transfer */
zx_writel_mask(vga->mmio + VGA_CMD_CFG, VGA_CMD_TRANS,
VGA_CMD_TRANS);
if (!wait_for_completion_timeout(&vga->complete,
msecs_to_jiffies(1000))) {
DRM_DEV_ERROR(vga->dev, "transfer timeout\n");
return -ETIMEDOUT;
}
cnt = zx_readl(vga->mmio + VGA_RXF_STATUS);
cnt = (cnt & VGA_RXF_COUNT_MASK) >> VGA_RXF_COUNT_SHIFT;
/* FIFO status may report more data than we need to read */
cnt = min_t(u32, len, cnt);
for (i = 0; i < cnt; i++)
*buf++ = zx_readl(vga->mmio + VGA_DATA);
len -= cnt;
offset += cnt;
}
return 0;
}
static int zx_vga_i2c_write(struct zx_vga *vga, struct i2c_msg *msg)
{
/*
* The DDC I2C adapter is only for reading EDID data, so we assume
* that the write to this adapter must be the EDID data offset.
*/
if ((msg->len != 1) || ((msg->addr != DDC_ADDR)))
return -EINVAL;
/* Hardware will take care of the slave address shifting */
zx_writel(vga->mmio + VGA_DEVICE_ADDR, msg->addr);
return 0;
}
static int zx_vga_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
int num)
{
struct zx_vga *vga = i2c_get_adapdata(adap);
struct zx_vga_i2c *ddc = vga->ddc;
int ret = 0;
int i;
mutex_lock(&ddc->lock);
for (i = 0; i < num; i++) {
if (msgs[i].flags & I2C_M_RD)
ret = zx_vga_i2c_read(vga, &msgs[i]);
else
ret = zx_vga_i2c_write(vga, &msgs[i]);
if (ret < 0)
break;
}
if (!ret)
ret = num;
mutex_unlock(&ddc->lock);
return ret;
}
static u32 zx_vga_i2c_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static const struct i2c_algorithm zx_vga_algorithm = {
.master_xfer = zx_vga_i2c_xfer,
.functionality = zx_vga_i2c_func,
};
static int zx_vga_ddc_register(struct zx_vga *vga)
{
struct device *dev = vga->dev;
struct i2c_adapter *adap;
struct zx_vga_i2c *ddc;
int ret;
ddc = devm_kzalloc(dev, sizeof(*ddc), GFP_KERNEL);
if (!ddc)
return -ENOMEM;
vga->ddc = ddc;
mutex_init(&ddc->lock);
adap = &ddc->adap;
adap->owner = THIS_MODULE;
adap->class = I2C_CLASS_DDC;
adap->dev.parent = dev;
adap->algo = &zx_vga_algorithm;
snprintf(adap->name, sizeof(adap->name), "zx vga i2c");
ret = i2c_add_adapter(adap);
if (ret) {
DRM_DEV_ERROR(dev, "failed to add I2C adapter: %d\n", ret);
return ret;
}
i2c_set_adapdata(adap, vga);
return 0;
}
static irqreturn_t zx_vga_irq_thread(int irq, void *dev_id)
{
struct zx_vga *vga = dev_id;
drm_helper_hpd_irq_event(vga->connector.dev);
return IRQ_HANDLED;
}
static irqreturn_t zx_vga_irq_handler(int irq, void *dev_id)
{
struct zx_vga *vga = dev_id;
u32 status;
status = zx_readl(vga->mmio + VGA_I2C_STATUS);
/* Clear interrupt status */
zx_writel_mask(vga->mmio + VGA_I2C_STATUS, VGA_CLEAR_IRQ,
VGA_CLEAR_IRQ);
if (status & VGA_DEVICE_CONNECTED) {
/*
* Since VGA_DETECT_SEL bits need to be reset for switching DDC
* bus from device detection to EDID read, rather than setting
* up HAS_DEVICE bit here, we need to do that in .get_modes
* hook for unplug detecting after EDID read succeeds.
*/
vga->connected = true;
return IRQ_WAKE_THREAD;
}
if (status & VGA_DEVICE_DISCONNECTED) {
zx_writel(vga->mmio + VGA_AUTO_DETECT_SEL,
VGA_DETECT_SEL_NO_DEVICE);
vga->connected = false;
return IRQ_WAKE_THREAD;
}
if (status & VGA_TRANS_DONE) {
complete(&vga->complete);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static void zx_vga_hw_init(struct zx_vga *vga)
{
unsigned long ref = clk_get_rate(vga->i2c_wclk);
int div;
/*
* Set up I2C fast speed divider per formula below to get 400kHz.
* scl = ref / ((div + 1) * 4)
*/
div = DIV_ROUND_UP(ref / 1000, 400 * 4) - 1;
zx_writel(vga->mmio + VGA_CLK_DIV_FS, div);
/* Set up device detection */
zx_writel(vga->mmio + VGA_AUTO_DETECT_PARA, 0x80);
zx_writel(vga->mmio + VGA_AUTO_DETECT_SEL, VGA_DETECT_SEL_NO_DEVICE);
/*
* We need to poke monitor via DDC bus to get connection irq
* start working.
*/
zx_writel(vga->mmio + VGA_DEVICE_ADDR, DDC_ADDR);
zx_writel_mask(vga->mmio + VGA_CMD_CFG, VGA_CMD_TRANS, VGA_CMD_TRANS);
}
static int zx_vga_bind(struct device *dev, struct device *master, void *data)
{
struct platform_device *pdev = to_platform_device(dev);
struct drm_device *drm = data;
struct resource *res;
struct zx_vga *vga;
int irq;
int ret;
vga = devm_kzalloc(dev, sizeof(*vga), GFP_KERNEL);
if (!vga)
return -ENOMEM;
vga->dev = dev;
dev_set_drvdata(dev, vga);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
vga->mmio = devm_ioremap_resource(dev, res);
if (IS_ERR(vga->mmio))
return PTR_ERR(vga->mmio);
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
vga->i2c_wclk = devm_clk_get(dev, "i2c_wclk");
if (IS_ERR(vga->i2c_wclk)) {
ret = PTR_ERR(vga->i2c_wclk);
DRM_DEV_ERROR(dev, "failed to get i2c_wclk: %d\n", ret);
return ret;
}
ret = zx_vga_pwrctrl_init(vga);
if (ret) {
DRM_DEV_ERROR(dev, "failed to init power control: %d\n", ret);
return ret;
}
ret = zx_vga_ddc_register(vga);
if (ret) {
DRM_DEV_ERROR(dev, "failed to register ddc: %d\n", ret);
return ret;
}
ret = zx_vga_register(drm, vga);
if (ret) {
DRM_DEV_ERROR(dev, "failed to register vga: %d\n", ret);
return ret;
}
init_completion(&vga->complete);
ret = devm_request_threaded_irq(dev, irq, zx_vga_irq_handler,
zx_vga_irq_thread, IRQF_SHARED,
dev_name(dev), vga);
if (ret) {
DRM_DEV_ERROR(dev, "failed to request threaded irq: %d\n", ret);
return ret;
}
ret = clk_prepare_enable(vga->i2c_wclk);
if (ret)
return ret;
zx_vga_hw_init(vga);
return 0;
}
static void zx_vga_unbind(struct device *dev, struct device *master,
void *data)
{
struct zx_vga *vga = dev_get_drvdata(dev);
clk_disable_unprepare(vga->i2c_wclk);
}
static const struct component_ops zx_vga_component_ops = {
.bind = zx_vga_bind,
.unbind = zx_vga_unbind,
};
static int zx_vga_probe(struct platform_device *pdev)
{
return component_add(&pdev->dev, &zx_vga_component_ops);
}
static int zx_vga_remove(struct platform_device *pdev)
{
component_del(&pdev->dev, &zx_vga_component_ops);
return 0;
}
static const struct of_device_id zx_vga_of_match[] = {
{ .compatible = "zte,zx296718-vga", },
{ /* end */ },
};
MODULE_DEVICE_TABLE(of, zx_vga_of_match);
struct platform_driver zx_vga_driver = {
.probe = zx_vga_probe,
.remove = zx_vga_remove,
.driver = {
.name = "zx-vga",
.of_match_table = zx_vga_of_match,
},
};