#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include "mtk_cec.h"
#include "mtk_drm_drv.h"
#define TR_CONFIG 0x00
#define CLEAR_CEC_IRQ BIT(15)
#define CEC_CKGEN 0x04
#define CEC_32K_PDN BIT(19)
#define PDN BIT(16)
#define RX_EVENT 0x54
#define HDMI_PORD BIT(25)
#define HDMI_HTPLG BIT(24)
#define HDMI_PORD_INT_EN BIT(9)
#define HDMI_HTPLG_INT_EN BIT(8)
#define RX_GEN_WD 0x58
#define HDMI_PORD_INT_32K_STATUS BIT(26)
#define RX_RISC_INT_32K_STATUS BIT(25)
#define HDMI_HTPLG_INT_32K_STATUS BIT(24)
#define HDMI_PORD_INT_32K_CLR BIT(18)
#define RX_INT_32K_CLR BIT(17)
#define HDMI_HTPLG_INT_32K_CLR BIT(16)
#define HDMI_PORD_INT_32K_STA_MASK BIT(10)
#define RX_RISC_INT_32K_STA_MASK BIT(9)
#define HDMI_HTPLG_INT_32K_STA_MASK BIT(8)
#define HDMI_PORD_INT_32K_EN BIT(2)
#define RX_INT_32K_EN BIT(1)
#define HDMI_HTPLG_INT_32K_EN BIT(0)
#define NORMAL_INT_CTRL 0x5C
#define HDMI_HTPLG_INT_STA BIT(0)
#define HDMI_PORD_INT_STA BIT(1)
#define HDMI_HTPLG_INT_CLR BIT(16)
#define HDMI_PORD_INT_CLR BIT(17)
#define HDMI_FULL_INT_CLR BIT(20)
struct mtk_cec {
void __iomem *regs;
struct clk *clk;
int irq;
bool hpd;
void (*hpd_event)(bool hpd, struct device *dev);
struct device *hdmi_dev;
spinlock_t lock;
};
static void mtk_cec_clear_bits(struct mtk_cec *cec, unsigned int offset,
unsigned int bits)
{
void __iomem *reg = cec->regs + offset;
u32 tmp;
tmp = readl(reg);
tmp &= ~bits;
writel(tmp, reg);
}
static void mtk_cec_set_bits(struct mtk_cec *cec, unsigned int offset,
unsigned int bits)
{
void __iomem *reg = cec->regs + offset;
u32 tmp;
tmp = readl(reg);
tmp |= bits;
writel(tmp, reg);
}
static void mtk_cec_mask(struct mtk_cec *cec, unsigned int offset,
unsigned int val, unsigned int mask)
{
u32 tmp = readl(cec->regs + offset) & ~mask;
tmp |= val & mask;
writel(tmp, cec->regs + offset);
}
void mtk_cec_set_hpd_event(struct device *dev,
void (*hpd_event)(bool hpd, struct device *dev),
struct device *hdmi_dev)
{
struct mtk_cec *cec = dev_get_drvdata(dev);
unsigned long flags;
spin_lock_irqsave(&cec->lock, flags);
cec->hdmi_dev = hdmi_dev;
cec->hpd_event = hpd_event;
spin_unlock_irqrestore(&cec->lock, flags);
}
EXPORT_SYMBOL_NS_GPL(mtk_cec_set_hpd_event, "DRM_MTK_HDMI_V1");
bool mtk_cec_hpd_high(struct device *dev)
{
struct mtk_cec *cec = dev_get_drvdata(dev);
unsigned int status;
status = readl(cec->regs + RX_EVENT);
return (status & (HDMI_PORD | HDMI_HTPLG)) == (HDMI_PORD | HDMI_HTPLG);
}
EXPORT_SYMBOL_NS_GPL(mtk_cec_hpd_high, "DRM_MTK_HDMI_V1");
static void mtk_cec_htplg_irq_init(struct mtk_cec *cec)
{
mtk_cec_mask(cec, CEC_CKGEN, 0 | CEC_32K_PDN, PDN | CEC_32K_PDN);
mtk_cec_set_bits(cec, RX_GEN_WD, HDMI_PORD_INT_32K_CLR |
RX_INT_32K_CLR | HDMI_HTPLG_INT_32K_CLR);
mtk_cec_mask(cec, RX_GEN_WD, 0, HDMI_PORD_INT_32K_CLR | RX_INT_32K_CLR |
HDMI_HTPLG_INT_32K_CLR | HDMI_PORD_INT_32K_EN |
RX_INT_32K_EN | HDMI_HTPLG_INT_32K_EN);
}
static void mtk_cec_htplg_irq_enable(struct mtk_cec *cec)
{
mtk_cec_set_bits(cec, RX_EVENT, HDMI_PORD_INT_EN | HDMI_HTPLG_INT_EN);
}
static void mtk_cec_htplg_irq_disable(struct mtk_cec *cec)
{
mtk_cec_clear_bits(cec, RX_EVENT, HDMI_PORD_INT_EN | HDMI_HTPLG_INT_EN);
}
static void mtk_cec_clear_htplg_irq(struct mtk_cec *cec)
{
mtk_cec_set_bits(cec, TR_CONFIG, CLEAR_CEC_IRQ);
mtk_cec_set_bits(cec, NORMAL_INT_CTRL, HDMI_HTPLG_INT_CLR |
HDMI_PORD_INT_CLR | HDMI_FULL_INT_CLR);
mtk_cec_set_bits(cec, RX_GEN_WD, HDMI_PORD_INT_32K_CLR |
RX_INT_32K_CLR | HDMI_HTPLG_INT_32K_CLR);
usleep_range(5, 10);
mtk_cec_clear_bits(cec, NORMAL_INT_CTRL, HDMI_HTPLG_INT_CLR |
HDMI_PORD_INT_CLR | HDMI_FULL_INT_CLR);
mtk_cec_clear_bits(cec, TR_CONFIG, CLEAR_CEC_IRQ);
mtk_cec_clear_bits(cec, RX_GEN_WD, HDMI_PORD_INT_32K_CLR |
RX_INT_32K_CLR | HDMI_HTPLG_INT_32K_CLR);
}
static void mtk_cec_hpd_event(struct mtk_cec *cec, bool hpd)
{
void (*hpd_event)(bool hpd, struct device *dev);
struct device *hdmi_dev;
unsigned long flags;
spin_lock_irqsave(&cec->lock, flags);
hpd_event = cec->hpd_event;
hdmi_dev = cec->hdmi_dev;
spin_unlock_irqrestore(&cec->lock, flags);
if (hpd_event)
hpd_event(hpd, hdmi_dev);
}
static irqreturn_t mtk_cec_htplg_isr_thread(int irq, void *arg)
{
struct device *dev = arg;
struct mtk_cec *cec = dev_get_drvdata(dev);
bool hpd;
mtk_cec_clear_htplg_irq(cec);
hpd = mtk_cec_hpd_high(dev);
if (cec->hpd != hpd) {
dev_dbg(dev, "hotplug event! cur hpd = %d, hpd = %d\n",
cec->hpd, hpd);
cec->hpd = hpd;
mtk_cec_hpd_event(cec, hpd);
}
return IRQ_HANDLED;
}
static int mtk_cec_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct mtk_cec *cec;
int ret;
cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL);
if (!cec)
return -ENOMEM;
platform_set_drvdata(pdev, cec);
spin_lock_init(&cec->lock);
cec->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(cec->regs))
return dev_err_probe(dev, PTR_ERR(cec->regs),
"Failed to ioremap cec\n");
cec->clk = devm_clk_get(dev, NULL);
if (IS_ERR(cec->clk))
return dev_err_probe(dev, PTR_ERR(cec->clk),
"Failed to get cec clock\n");
cec->irq = platform_get_irq(pdev, 0);
if (cec->irq < 0)
return cec->irq;
ret = devm_request_threaded_irq(dev, cec->irq, NULL,
mtk_cec_htplg_isr_thread,
IRQF_SHARED | IRQF_TRIGGER_LOW |
IRQF_ONESHOT, "hdmi hpd", dev);
if (ret)
return dev_err_probe(dev, ret, "Failed to register cec irq\n");
ret = clk_prepare_enable(cec->clk);
if (ret)
return dev_err_probe(dev, ret, "Failed to enable cec clock\n");
mtk_cec_htplg_irq_init(cec);
mtk_cec_htplg_irq_enable(cec);
return 0;
}
static void mtk_cec_remove(struct platform_device *pdev)
{
struct mtk_cec *cec = platform_get_drvdata(pdev);
mtk_cec_htplg_irq_disable(cec);
clk_disable_unprepare(cec->clk);
}
static const struct of_device_id mtk_cec_of_ids[] = {
{ .compatible = "mediatek,mt8173-cec", },
{}
};
MODULE_DEVICE_TABLE(of, mtk_cec_of_ids);
struct platform_driver mtk_cec_driver = {
.probe = mtk_cec_probe,
.remove = mtk_cec_remove,
.driver = {
.name = "mediatek-cec",
.of_match_table = mtk_cec_of_ids,
},
};
module_platform_driver(mtk_cec_driver);
MODULE_DESCRIPTION("MediaTek HDMI CEC Driver");
MODULE_LICENSE("GPL");
