diff options
Diffstat (limited to 'drivers/gpu/drm/mediatek/mtk_cec.c')
| -rw-r--r-- | drivers/gpu/drm/mediatek/mtk_cec.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/drivers/gpu/drm/mediatek/mtk_cec.c b/drivers/gpu/drm/mediatek/mtk_cec.c new file mode 100644 index 000000000..cdfa64891 --- /dev/null +++ b/drivers/gpu/drm/mediatek/mtk_cec.c @@ -0,0 +1,258 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2014 MediaTek Inc. + * Author: Jie Qiu <jie.qiu@mediatek.com> + */ +#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" + +#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); +} + +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); +} + +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; + struct resource *res; + int ret; + + cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL); + if (!cec) + return -ENOMEM; + + platform_set_drvdata(pdev, cec); + spin_lock_init(&cec->lock); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + cec->regs = devm_ioremap_resource(dev, res); + if (IS_ERR(cec->regs)) { + ret = PTR_ERR(cec->regs); + dev_err(dev, "Failed to ioremap cec: %d\n", ret); + return ret; + } + + cec->clk = devm_clk_get(dev, NULL); + if (IS_ERR(cec->clk)) { + ret = PTR_ERR(cec->clk); + dev_err(dev, "Failed to get cec clock: %d\n", ret); + return ret; + } + + 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) { + dev_err(dev, "Failed to register cec irq: %d\n", ret); + return ret; + } + + ret = clk_prepare_enable(cec->clk); + if (ret) { + dev_err(dev, "Failed to enable cec clock: %d\n", ret); + return ret; + } + + mtk_cec_htplg_irq_init(cec); + mtk_cec_htplg_irq_enable(cec); + + return 0; +} + +static int 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); + return 0; +} + +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, + }, +}; |