1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2023 MediaTek Inc.
  4 */
  5
  6#include <linux/clk.h>
  7#include <linux/component.h>
  8#include <linux/module.h>
  9#include <linux/of_device.h>
 10#include <linux/platform_device.h>
 11#include <linux/pm_runtime.h>
 12#include <linux/soc/mediatek/mtk-cmdq.h>
 13
 14#include "mtk_disp_drv.h"
 15#include "mtk_drm_crtc.h"
 16#include "mtk_drm_ddp_comp.h"
 17
 18#define PADDING_CONTROL_REG	0x00
 19#define PADDING_BYPASS			BIT(0)
 20#define PADDING_ENABLE			BIT(1)
 21#define PADDING_PIC_SIZE_REG	0x04
 22#define PADDING_H_REG		0x08 /* horizontal */
 23#define PADDING_V_REG		0x0c /* vertical */
 24#define PADDING_COLOR_REG	0x10
 25
 26/**
 27 * struct mtk_padding - Basic information of the Padding
 28 * @clk: Clock of the module
 29 * @reg: Virtual address of the Padding for CPU to access
 30 * @cmdq_reg: CMDQ setting of the Padding
 31 *
 32 * Every Padding should have different clock source, register base, and
 33 * CMDQ settings, we stored these differences all together.
 34 */
 35struct mtk_padding {
 36	struct clk		*clk;
 37	void __iomem		*reg;
 38	struct cmdq_client_reg	cmdq_reg;
 39};
 40
 41int mtk_padding_clk_enable(struct device *dev)
 42{
 43	struct mtk_padding *padding = dev_get_drvdata(dev);
 44
 45	return clk_prepare_enable(padding->clk);
 46}
 47
 48void mtk_padding_clk_disable(struct device *dev)
 49{
 50	struct mtk_padding *padding = dev_get_drvdata(dev);
 51
 52	clk_disable_unprepare(padding->clk);
 53}
 54
 55void mtk_padding_start(struct device *dev)
 56{
 57	struct mtk_padding *padding = dev_get_drvdata(dev);
 58
 59	writel(PADDING_ENABLE | PADDING_BYPASS,
 60	       padding->reg + PADDING_CONTROL_REG);
 61
 62	/*
 63	 * Notice that even the padding is in bypass mode,
 64	 * all the settings must be cleared to 0 or
 65	 * undefined behaviors could happen
 66	 */
 67	writel(0, padding->reg + PADDING_PIC_SIZE_REG);
 68	writel(0, padding->reg + PADDING_H_REG);
 69	writel(0, padding->reg + PADDING_V_REG);
 70	writel(0, padding->reg + PADDING_COLOR_REG);
 71}
 72
 73void mtk_padding_stop(struct device *dev)
 74{
 75	struct mtk_padding *padding = dev_get_drvdata(dev);
 76
 77	writel(0, padding->reg + PADDING_CONTROL_REG);
 78}
 79
 80static int mtk_padding_bind(struct device *dev, struct device *master, void *data)
 81{
 82	return 0;
 83}
 84
 85static void mtk_padding_unbind(struct device *dev, struct device *master, void *data)
 86{
 87}
 88
 89static const struct component_ops mtk_padding_component_ops = {
 90	.bind	= mtk_padding_bind,
 91	.unbind = mtk_padding_unbind,
 92};
 93
 94static int mtk_padding_probe(struct platform_device *pdev)
 95{
 96	struct device *dev = &pdev->dev;
 97	struct mtk_padding *priv;
 98	struct resource *res;
 99	int ret;
100
101	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
102	if (!priv)
103		return -ENOMEM;
104
105	priv->clk = devm_clk_get(dev, NULL);
106	if (IS_ERR(priv->clk)) {
107		dev_err(dev, "failed to get clk\n");
108		return PTR_ERR(priv->clk);
109	}
110
111	priv->reg = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
112	if (IS_ERR(priv->reg)) {
113		dev_err(dev, "failed to do ioremap\n");
114		return PTR_ERR(priv->reg);
115	}
116
117#if IS_REACHABLE(CONFIG_MTK_CMDQ)
118	ret = cmdq_dev_get_client_reg(dev, &priv->cmdq_reg, 0);
119	if (ret) {
120		dev_err(dev, "failed to get gce client reg\n");
121		return ret;
122	}
123#endif
124
125	platform_set_drvdata(pdev, priv);
126
127	ret = devm_pm_runtime_enable(dev);
128	if (ret)
129		return ret;
130
131	ret = component_add(dev, &mtk_padding_component_ops);
132	if (ret) {
133		pm_runtime_disable(dev);
134		return dev_err_probe(dev, ret, "failed to add component\n");
135	}
136
137	return 0;
138}
139
140static int mtk_padding_remove(struct platform_device *pdev)
141{
142	component_del(&pdev->dev, &mtk_padding_component_ops);
143	return 0;
144}
145
146static const struct of_device_id mtk_padding_driver_dt_match[] = {
147	{ .compatible = "mediatek,mt8188-disp-padding" },
148	{ /* sentinel */ }
149};
150MODULE_DEVICE_TABLE(of, mtk_padding_driver_dt_match);
151
152struct platform_driver mtk_padding_driver = {
153	.probe		= mtk_padding_probe,
154	.remove		= mtk_padding_remove,
155	.driver		= {
156		.name	= "mediatek-disp-padding",
157		.owner	= THIS_MODULE,
158		.of_match_table = mtk_padding_driver_dt_match,
159	},
160};