drivers/gpu/drm/mediatek/mtk_padding.c

   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  */
  35 struct mtk_padding {
  36         struct clk              *clk;
  37         void __iomem            *reg;
  38         struct cmdq_client_reg  cmdq_reg;
  39 };
  40
  41 int 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
  48 void 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
  55 void 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
  73 void 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
  80 static int mtk_padding_bind(struct device *dev, struct device *master, void *data)
  81 {
  82         return 0;
  83 }
  84
  85 static void mtk_padding_unbind(struct device *dev, struct device *master, void *data)
  86 {
  87 }
  88
  89 static const struct component_ops mtk_padding_component_ops = {
  90         .bind   = mtk_padding_bind,
  91         .unbind = mtk_padding_unbind,
  92 };
  93
  94 static 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                 return dev_err_probe(dev, PTR_ERR(priv->clk),
 108                                      "failed to get clk\n");
 109
 110         priv->reg = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 111         if (IS_ERR(priv->reg))
 112                 return dev_err_probe(dev, PTR_ERR(priv->reg),
 113                                      "failed to do ioremap\n");
 114
 115 #if IS_REACHABLE(CONFIG_MTK_CMDQ)
 116         ret = cmdq_dev_get_client_reg(dev, &priv->cmdq_reg, 0);
 117         if (ret)
 118                 return dev_err_probe(dev, ret, "failed to get gce client reg\n");
 119 #endif
 120
 121         platform_set_drvdata(pdev, 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, ret, "failed to add component\n");
 131         }
 132
 133         return 0;
 134 }
 135
 136 static void mtk_padding_remove(struct platform_device *pdev)
 137 {
 138         component_del(&pdev->dev, &mtk_padding_component_ops);
 139 }
 140
 141 static const struct of_device_id mtk_padding_driver_dt_match[] = {
 142         { .compatible = "mediatek,mt8188-disp-padding" },
 143         { /* sentinel */ }
 144 };
 145 MODULE_DEVICE_TABLE(of, mtk_padding_driver_dt_match);
 146
 147 struct 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 };