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         bool supports_endianness;
  39 };
  40
  41 static void canvas_write(struct meson_canvas *canvas, u32 reg, u32 val)
  42 {
  43         writel_relaxed(val, canvas->reg_base + reg);
  44 }
  45
  46 static u32 canvas_read(struct meson_canvas *canvas, u32 reg)
  47 {
  48         return readl_relaxed(canvas->reg_base + reg);
  49 }
  50
  51 struct meson_canvas *meson_canvas_get(struct device *dev)
  52 {
  53         struct device_node *canvas_node;
  54         struct platform_device *canvas_pdev;
  55         struct meson_canvas *canvas;
  56
  57         canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
  58         if (!canvas_node)
  59                 return ERR_PTR(-ENODEV);
  60
  61         canvas_pdev = of_find_device_by_node(canvas_node);
  62         if (!canvas_pdev) {
  63                 of_node_put(canvas_node);
  64                 return ERR_PTR(-EPROBE_DEFER);
  65         }
  66
  67         of_node_put(canvas_node);
  68
  69         /*
  70          * If priv is NULL, it's probably because the canvas hasn't
  71          * properly initialized. Bail out with -EINVAL because, in the
  72          * current state, this driver probe cannot return -EPROBE_DEFER
  73          */
  74         canvas = dev_get_drvdata(&canvas_pdev->dev);
  75         if (!canvas) {
  76                 put_device(&canvas_pdev->dev);
  77                 return ERR_PTR(-EINVAL);
  78         }
  79
  80         return canvas;
  81 }
  82 EXPORT_SYMBOL_GPL(meson_canvas_get);
  83
  84 int meson_canvas_config(struct meson_canvas *canvas, u8 canvas_index,
  85                         u32 addr, u32 stride, u32 height,
  86                         unsigned int wrap,
  87                         unsigned int blkmode,
  88                         unsigned int endian)
  89 {
  90         unsigned long flags;
  91
  92         if (endian && !canvas->supports_endianness) {
  93                 dev_err(canvas->dev,
  94                         "Endianness is not supported on this SoC\n");
  95                 return -EINVAL;
  96         }
  97
  98         spin_lock_irqsave(&canvas->lock, flags);
  99         if (!canvas->used[canvas_index]) {
 100                 dev_err(canvas->dev,
 101                         "Trying to setup non allocated canvas %u\n",
 102                         canvas_index);
 103                 spin_unlock_irqrestore(&canvas->lock, flags);
 104                 return -EINVAL;
 105         }
 106
 107         canvas_write(canvas, DMC_CAV_LUT_DATAL,
 108                      ((addr + 7) >> 3) |
 109                      (((stride + 7) >> 3) << CANVAS_WIDTH_LBIT));
 110
 111         canvas_write(canvas, DMC_CAV_LUT_DATAH,
 112                      ((((stride + 7) >> 3) >> CANVAS_WIDTH_LWID) <<
 113                                                 CANVAS_WIDTH_HBIT) |
 114                      (height << CANVAS_HEIGHT_BIT) |
 115                      (wrap << CANVAS_WRAP_BIT) |
 116                      (blkmode << CANVAS_BLKMODE_BIT) |
 117                      (endian << CANVAS_ENDIAN_BIT));
 118
 119         canvas_write(canvas, DMC_CAV_LUT_ADDR,
 120                      CANVAS_LUT_WR_EN | canvas_index);
 121
 122         /* Force a read-back to make sure everything is flushed. */
 123         canvas_read(canvas, DMC_CAV_LUT_DATAH);
 124         spin_unlock_irqrestore(&canvas->lock, flags);
 125
 126         return 0;
 127 }
 128 EXPORT_SYMBOL_GPL(meson_canvas_config);
 129
 130 int meson_canvas_alloc(struct meson_canvas *canvas, u8 *canvas_index)
 131 {
 132         int i;
 133         unsigned long flags;
 134
 135         spin_lock_irqsave(&canvas->lock, flags);
 136         for (i = 0; i < NUM_CANVAS; ++i) {
 137                 if (!canvas->used[i]) {
 138                         canvas->used[i] = 1;
 139                         spin_unlock_irqrestore(&canvas->lock, flags);
 140                         *canvas_index = i;
 141                         return 0;
 142                 }
 143         }
 144         spin_unlock_irqrestore(&canvas->lock, flags);
 145
 146         dev_err(canvas->dev, "No more canvas available\n");
 147         return -ENODEV;
 148 }
 149 EXPORT_SYMBOL_GPL(meson_canvas_alloc);
 150
 151 int meson_canvas_free(struct meson_canvas *canvas, u8 canvas_index)
 152 {
 153         unsigned long flags;
 154
 155         spin_lock_irqsave(&canvas->lock, flags);
 156         if (!canvas->used[canvas_index]) {
 157                 dev_err(canvas->dev,
 158                         "Trying to free unused canvas %u\n", canvas_index);
 159                 spin_unlock_irqrestore(&canvas->lock, flags);
 160                 return -EINVAL;
 161         }
 162         canvas->used[canvas_index] = 0;
 163         spin_unlock_irqrestore(&canvas->lock, flags);
 164
 165         return 0;
 166 }
 167 EXPORT_SYMBOL_GPL(meson_canvas_free);
 168
 169 static int meson_canvas_probe(struct platform_device *pdev)
 170 {
 171         struct resource *res;
 172         struct meson_canvas *canvas;
 173         struct device *dev = &pdev->dev;
 174
 175         canvas = devm_kzalloc(dev, sizeof(*canvas), GFP_KERNEL);
 176         if (!canvas)
 177                 return -ENOMEM;
 178
 179         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 180         canvas->reg_base = devm_ioremap_resource(dev, res);
 181         if (IS_ERR(canvas->reg_base))
 182                 return PTR_ERR(canvas->reg_base);
 183
 184         canvas->supports_endianness = of_device_get_match_data(dev);
 185
 186         canvas->dev = dev;
 187         spin_lock_init(&canvas->lock);
 188         dev_set_drvdata(dev, canvas);
 189
 190         return 0;
 191 }
 192
 193 static const struct of_device_id canvas_dt_match[] = {
 194         { .compatible = "amlogic,meson8-canvas", .data = (void *)false, },
 195         { .compatible = "amlogic,meson8b-canvas", .data = (void *)false, },
 196         { .compatible = "amlogic,meson8m2-canvas", .data = (void *)false, },
 197         { .compatible = "amlogic,canvas", .data = (void *)true, },
 198         {}
 199 };
 200 MODULE_DEVICE_TABLE(of, canvas_dt_match);
 201
 202 static struct platform_driver meson_canvas_driver = {
 203         .probe = meson_canvas_probe,
 204         .driver = {
 205                 .name = "amlogic-canvas",
 206                 .of_match_table = canvas_dt_match,
 207         },
 208 };
 209 module_platform_driver(meson_canvas_driver);
 210
 211 MODULE_DESCRIPTION("Amlogic Canvas driver");
 212 MODULE_AUTHOR("Maxime Jourdan <mjourdan@baylibre.com>");
 213 MODULE_LICENSE("GPL");