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_crtc.h"
15#include "mtk_ddp_comp.h"
16#include "mtk_disp_drv.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(clk: 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(clk: 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 addr: 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(val: 0, addr: padding->reg + PADDING_PIC_SIZE_REG);
68 writel(val: 0, addr: padding->reg + PADDING_H_REG);
69 writel(val: 0, addr: padding->reg + PADDING_V_REG);
70 writel(val: 0, addr: 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(val: 0, addr: 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, size: sizeof(*priv), GFP_KERNEL);
102 if (!priv)
103 return -ENOMEM;
104
105 priv->clk = devm_clk_get(dev, NULL);
106 if (IS_ERR(ptr: priv->clk))
107 return dev_err_probe(dev, err: PTR_ERR(ptr: priv->clk),
108 fmt: "failed to get clk\n");
109
110 priv->reg = devm_platform_get_and_ioremap_resource(pdev, index: 0, res: &res);
111 if (IS_ERR(ptr: priv->reg))
112 return dev_err_probe(dev, err: PTR_ERR(ptr: priv->reg),
113 fmt: "failed to do ioremap\n");
114
115#if IS_REACHABLE(CONFIG_MTK_CMDQ)
116 ret = cmdq_dev_get_client_reg(dev, client_reg: &priv->cmdq_reg, idx: 0);
117 if (ret)
118 return dev_err_probe(dev, err: ret, fmt: "failed to get gce client reg\n");
119#endif
120
121 platform_set_drvdata(pdev, data: priv);
122
123 ret = devm_pm_runtime_enable(dev);
124 if (ret)
125 return ret;
126
127 ret = component_add(dev, &mtk_padding_component_ops);
128 if (ret) {
129 pm_runtime_disable(dev);
130 return dev_err_probe(dev, err: ret, fmt: "failed to add component\n");
131 }
132
133 return 0;
134}
135
136static void mtk_padding_remove(struct platform_device *pdev)
137{
138 component_del(&pdev->dev, &mtk_padding_component_ops);
139}
140
141static const struct of_device_id mtk_padding_driver_dt_match[] = {
142 { .compatible = "mediatek,mt8188-disp-padding" },
143 { /* sentinel */ }
144};
145MODULE_DEVICE_TABLE(of, mtk_padding_driver_dt_match);
146
147struct platform_driver mtk_padding_driver = {
148 .probe = mtk_padding_probe,
149 .remove = mtk_padding_remove,
150 .driver = {
151 .name = "mediatek-disp-padding",
152 .of_match_table = mtk_padding_driver_dt_match,
153 },
154};
155

source code of linux/drivers/gpu/drm/mediatek/mtk_padding.c