drivers/soc/amlogic/meson-canvas.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2018 BayLibre, SAS
   4  * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
   5  * Copyright (C) 2014 Endless Mobile
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/mfd/syscon.h>
  10 #include <linux/module.h>
  11 #include <linux/regmap.h>
  12 #include <linux/soc/amlogic/meson-canvas.h>
  13 #include <linux/of_address.h>
  14 #include <linux/of_platform.h>
  15 #include <linux/io.h>
  16
  17 #define NUM_CANVAS 256
  18
  19 /* DMC Registers */
  20 #define DMC_CAV_LUT_DATAL       0x00
  21         #define CANVAS_WIDTH_LBIT       29
  22         #define CANVAS_WIDTH_LWID       3
  23 #define DMC_CAV_LUT_DATAH       0x04
  24         #define CANVAS_WIDTH_HBIT       0
  25         #define CANVAS_HEIGHT_BIT       9
  26         #define CANVAS_WRAP_BIT         22
  27         #define CANVAS_BLKMODE_BIT      24
  28         #define CANVAS_ENDIAN_BIT       26
  29 #define DMC_CAV_LUT_ADDR        0x08
  30         #define CANVAS_LUT_WR_EN        BIT(9)
  31         #define CANVAS_LUT_RD_EN        BIT(8)
  32
  33 struct meson_canvas {
  34         struct device *dev;
  35         void __iomem *reg_base;
  36         spinlock_t lock; /* canvas device lock */
  37         u8 used[NUM_CANVAS];
  38 };
  39
  40 static void canvas_write(struct meson_canvas *canvas, u32 reg, u32 val)
  41 {
  42         writel_relaxed(val, canvas->reg_base + reg);
  43 }
  44
  45 static u32 canvas_read(struct meson_canvas *canvas, u32 reg)
  46 {
  47         return readl_relaxed(canvas->reg_base + reg);
  48 }
  49
  50 struct meson_canvas *meson_canvas_get(struct device *dev)
  51 {
  52         struct device_node *canvas_node;
  53         struct platform_device *canvas_pdev;
  54         struct meson_canvas *canvas;
  55
  56         canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
  57         if (!canvas_node)
  58                 return ERR_PTR(-ENODEV);
  59
  60         canvas_pdev = of_find_device_by_node(canvas_node);
  61         if (!canvas_pdev) {
  62                 of_node_put(canvas_node);
  63                 return ERR_PTR(-EPROBE_DEFER);
  64         }
  65
  66         of_node_put(canvas_node);
  67
  68         /*
  69          * If priv is NULL, it's probably because the canvas hasn't
  70          * properly initialized. Bail out with -EINVAL because, in the
  71          * current state, this driver probe cannot return -EPROBE_DEFER
  72          */
  73         canvas = dev_get_drvdata(&canvas_pdev->dev);
  74         if (!canvas)
  75                 return ERR_PTR(-EINVAL);
  76
  77         return canvas;
  78 }
  79 EXPORT_SYMBOL_GPL(meson_canvas_get);
  80
  81 int meson_canvas_config(struct meson_canvas *canvas, u8 canvas_index,
  82                         u32 addr, u32 stride, u32 height,
  83                         unsigned int wrap,
  84                         unsigned int blkmode,
  85                         unsigned int endian)
  86 {
  87         unsigned long flags;
  88
  89         spin_lock_irqsave(&canvas->lock, flags);
  90         if (!canvas->used[canvas_index]) {
  91                 dev_err(canvas->dev,
  92                         "Trying to setup non allocated canvas %u\n",
  93                         canvas_index);
  94                 spin_unlock_irqrestore(&canvas->lock, flags);
  95                 return -EINVAL;
  96         }
  97
  98         canvas_write(canvas, DMC_CAV_LUT_DATAL,
  99                      ((addr + 7) >> 3) |
 100                      (((stride + 7) >> 3) << CANVAS_WIDTH_LBIT));
 101
 102         canvas_write(canvas, DMC_CAV_LUT_DATAH,
 103                      ((((stride + 7) >> 3) >> CANVAS_WIDTH_LWID) <<
 104                                                 CANVAS_WIDTH_HBIT) |
 105                      (height << CANVAS_HEIGHT_BIT) |
 106                      (wrap << CANVAS_WRAP_BIT) |
 107                      (blkmode << CANVAS_BLKMODE_BIT) |
 108                      (endian << CANVAS_ENDIAN_BIT));
 109
 110         canvas_write(canvas, DMC_CAV_LUT_ADDR,
 111                      CANVAS_LUT_WR_EN | canvas_index);
 112
 113         /* Force a read-back to make sure everything is flushed. */
 114         canvas_read(canvas, DMC_CAV_LUT_DATAH);
 115         spin_unlock_irqrestore(&canvas->lock, flags);
 116
 117         return 0;
 118 }
 119 EXPORT_SYMBOL_GPL(meson_canvas_config);
 120
 121 int meson_canvas_alloc(struct meson_canvas *canvas, u8 *canvas_index)
 122 {
 123         int i;
 124         unsigned long flags;
 125
 126         spin_lock_irqsave(&canvas->lock, flags);
 127         for (i = 0; i < NUM_CANVAS; ++i) {
 128                 if (!canvas->used[i]) {
 129                         canvas->used[i] = 1;
 130                         spin_unlock_irqrestore(&canvas->lock, flags);
 131                         *canvas_index = i;
 132                         return 0;
 133                 }
 134         }
 135         spin_unlock_irqrestore(&canvas->lock, flags);
 136
 137         dev_err(canvas->dev, "No more canvas available\n");
 138         return -ENODEV;
 139 }
 140 EXPORT_SYMBOL_GPL(meson_canvas_alloc);
 141
 142 int meson_canvas_free(struct meson_canvas *canvas, u8 canvas_index)
 143 {
 144         unsigned long flags;
 145
 146         spin_lock_irqsave(&canvas->lock, flags);
 147         if (!canvas->used[canvas_index]) {
 148                 dev_err(canvas->dev,
 149                         "Trying to free unused canvas %u\n", canvas_index);
 150                 spin_unlock_irqrestore(&canvas->lock, flags);
 151                 return -EINVAL;
 152         }
 153         canvas->used[canvas_index] = 0;
 154         spin_unlock_irqrestore(&canvas->lock, flags);
 155
 156         return 0;
 157 }
 158 EXPORT_SYMBOL_GPL(meson_canvas_free);
 159
 160 static int meson_canvas_probe(struct platform_device *pdev)
 161 {
 162         struct resource *res;
 163         struct meson_canvas *canvas;
 164         struct device *dev = &pdev->dev;
 165
 166         canvas = devm_kzalloc(dev, sizeof(*canvas), GFP_KERNEL);
 167         if (!canvas)
 168                 return -ENOMEM;
 169
 170         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 171         canvas->reg_base = devm_ioremap_resource(dev, res);
 172         if (IS_ERR(canvas->reg_base))
 173                 return PTR_ERR(canvas->reg_base);
 174
 175         canvas->dev = dev;
 176         spin_lock_init(&canvas->lock);
 177         dev_set_drvdata(dev, canvas);
 178
 179         return 0;
 180 }
 181
 182 static const struct of_device_id canvas_dt_match[] = {
 183         { .compatible = "amlogic,canvas" },
 184         {}
 185 };
 186 MODULE_DEVICE_TABLE(of, canvas_dt_match);
 187
 188 static struct platform_driver meson_canvas_driver = {
 189         .probe = meson_canvas_probe,
 190         .driver = {
 191                 .name = "amlogic-canvas",
 192                 .of_match_table = canvas_dt_match,
 193         },
 194 };
 195 module_platform_driver(meson_canvas_driver);
 196
 197 MODULE_DESCRIPTION("Amlogic Canvas driver");
 198 MODULE_AUTHOR("Maxime Jourdan <mjourdan@baylibre.com>");
 199 MODULE_LICENSE("GPL");