drivers/gpu/drm/sun4i/sun8i_tcon_top.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /* Copyright (c) 2018 Jernej Skrabec <jernej.skrabec@siol.net> */
   3
   4 #include <drm/drmP.h>
   5
   6 #include <dt-bindings/clock/sun8i-tcon-top.h>
   7
   8 #include <linux/bitfield.h>
   9 #include <linux/component.h>
  10 #include <linux/device.h>
  11 #include <linux/module.h>
  12 #include <linux/of_graph.h>
  13 #include <linux/platform_device.h>
  14
  15 #include "sun8i_tcon_top.h"
  16
  17 static bool sun8i_tcon_top_node_is_tcon_top(struct device_node *node)
  18 {
  19         return !!of_match_node(sun8i_tcon_top_of_table, node);
  20 }
  21
  22 int sun8i_tcon_top_set_hdmi_src(struct device *dev, int tcon)
  23 {
  24         struct sun8i_tcon_top *tcon_top = dev_get_drvdata(dev);
  25         unsigned long flags;
  26         u32 val;
  27
  28         if (!sun8i_tcon_top_node_is_tcon_top(dev->of_node)) {
  29                 dev_err(dev, "Device is not TCON TOP!\n");
  30                 return -EINVAL;
  31         }
  32
  33         if (tcon < 2 || tcon > 3) {
  34                 dev_err(dev, "TCON index must be 2 or 3!\n");
  35                 return -EINVAL;
  36         }
  37
  38         spin_lock_irqsave(&tcon_top->reg_lock, flags);
  39
  40         val = readl(tcon_top->regs + TCON_TOP_GATE_SRC_REG);
  41         val &= ~TCON_TOP_HDMI_SRC_MSK;
  42         val |= FIELD_PREP(TCON_TOP_HDMI_SRC_MSK, tcon - 1);
  43         writel(val, tcon_top->regs + TCON_TOP_GATE_SRC_REG);
  44
  45         spin_unlock_irqrestore(&tcon_top->reg_lock, flags);
  46
  47         return 0;
  48 }
  49 EXPORT_SYMBOL(sun8i_tcon_top_set_hdmi_src);
  50
  51 int sun8i_tcon_top_de_config(struct device *dev, int mixer, int tcon)
  52 {
  53         struct sun8i_tcon_top *tcon_top = dev_get_drvdata(dev);
  54         unsigned long flags;
  55         u32 reg;
  56
  57         if (!sun8i_tcon_top_node_is_tcon_top(dev->of_node)) {
  58                 dev_err(dev, "Device is not TCON TOP!\n");
  59                 return -EINVAL;
  60         }
  61
  62         if (mixer > 1) {
  63                 dev_err(dev, "Mixer index is too high!\n");
  64                 return -EINVAL;
  65         }
  66
  67         if (tcon > 3) {
  68                 dev_err(dev, "TCON index is too high!\n");
  69                 return -EINVAL;
  70         }
  71
  72         spin_lock_irqsave(&tcon_top->reg_lock, flags);
  73
  74         reg = readl(tcon_top->regs + TCON_TOP_PORT_SEL_REG);
  75         if (mixer == 0) {
  76                 reg &= ~TCON_TOP_PORT_DE0_MSK;
  77                 reg |= FIELD_PREP(TCON_TOP_PORT_DE0_MSK, tcon);
  78         } else {
  79                 reg &= ~TCON_TOP_PORT_DE1_MSK;
  80                 reg |= FIELD_PREP(TCON_TOP_PORT_DE1_MSK, tcon);
  81         }
  82         writel(reg, tcon_top->regs + TCON_TOP_PORT_SEL_REG);
  83
  84         spin_unlock_irqrestore(&tcon_top->reg_lock, flags);
  85
  86         return 0;
  87 }
  88 EXPORT_SYMBOL(sun8i_tcon_top_de_config);
  89
  90
  91 static struct clk_hw *sun8i_tcon_top_register_gate(struct device *dev,
  92                                                    const char *parent,
  93                                                    void __iomem *regs,
  94                                                    spinlock_t *lock,
  95                                                    u8 bit, int name_index)
  96 {
  97         const char *clk_name, *parent_name;
  98         int ret, index;
  99
 100         index = of_property_match_string(dev->of_node, "clock-names", parent);
 101         if (index < 0)
 102                 return ERR_PTR(index);
 103
 104         parent_name = of_clk_get_parent_name(dev->of_node, index);
 105
 106         ret = of_property_read_string_index(dev->of_node,
 107                                             "clock-output-names", name_index,
 108                                             &clk_name);
 109         if (ret)
 110                 return ERR_PTR(ret);
 111
 112         return clk_hw_register_gate(dev, clk_name, parent_name,
 113                                     CLK_SET_RATE_PARENT,
 114                                     regs + TCON_TOP_GATE_SRC_REG,
 115                                     bit, 0, lock);
 116 };
 117
 118 static int sun8i_tcon_top_bind(struct device *dev, struct device *master,
 119                                void *data)
 120 {
 121         struct platform_device *pdev = to_platform_device(dev);
 122         struct clk_hw_onecell_data *clk_data;
 123         struct sun8i_tcon_top *tcon_top;
 124         struct resource *res;
 125         void __iomem *regs;
 126         int ret, i;
 127
 128         tcon_top = devm_kzalloc(dev, sizeof(*tcon_top), GFP_KERNEL);
 129         if (!tcon_top)
 130                 return -ENOMEM;
 131
 132         clk_data = devm_kzalloc(dev, sizeof(*clk_data) +
 133                                 sizeof(*clk_data->hws) * CLK_NUM,
 134                                 GFP_KERNEL);
 135         if (!clk_data)
 136                 return -ENOMEM;
 137         tcon_top->clk_data = clk_data;
 138
 139         spin_lock_init(&tcon_top->reg_lock);
 140
 141         tcon_top->rst = devm_reset_control_get(dev, NULL);
 142         if (IS_ERR(tcon_top->rst)) {
 143                 dev_err(dev, "Couldn't get our reset line\n");
 144                 return PTR_ERR(tcon_top->rst);
 145         }
 146
 147         tcon_top->bus = devm_clk_get(dev, "bus");
 148         if (IS_ERR(tcon_top->bus)) {
 149                 dev_err(dev, "Couldn't get the bus clock\n");
 150                 return PTR_ERR(tcon_top->bus);
 151         }
 152
 153         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 154         regs = devm_ioremap_resource(dev, res);
 155         tcon_top->regs = regs;
 156         if (IS_ERR(regs))
 157                 return PTR_ERR(regs);
 158
 159         ret = reset_control_deassert(tcon_top->rst);
 160         if (ret) {
 161                 dev_err(dev, "Could not deassert ctrl reset control\n");
 162                 return ret;
 163         }
 164
 165         ret = clk_prepare_enable(tcon_top->bus);
 166         if (ret) {
 167                 dev_err(dev, "Could not enable bus clock\n");
 168                 goto err_assert_reset;
 169         }
 170
 171         /*
 172          * At least on H6, some registers have some bits set by default
 173          * which may cause issues. Clear them here.
 174          */
 175         writel(0, regs + TCON_TOP_PORT_SEL_REG);
 176         writel(0, regs + TCON_TOP_GATE_SRC_REG);
 177
 178         /*
 179          * TCON TOP has two muxes, which select parent clock for each TCON TV
 180          * channel clock. Parent could be either TCON TV or TVE clock. For now
 181          * we leave this fixed to TCON TV, since TVE driver for R40 is not yet
 182          * implemented. Once it is, graph needs to be traversed to determine
 183          * if TVE is active on each TCON TV. If it is, mux should be switched
 184          * to TVE clock parent.
 185          */
 186         clk_data->hws[CLK_TCON_TOP_TV0] =
 187                 sun8i_tcon_top_register_gate(dev, "tcon-tv0", regs,
 188                                              &tcon_top->reg_lock,
 189                                              TCON_TOP_TCON_TV0_GATE, 0);
 190
 191         clk_data->hws[CLK_TCON_TOP_TV1] =
 192                 sun8i_tcon_top_register_gate(dev, "tcon-tv1", regs,
 193                                              &tcon_top->reg_lock,
 194                                              TCON_TOP_TCON_TV1_GATE, 1);
 195
 196         clk_data->hws[CLK_TCON_TOP_DSI] =
 197                 sun8i_tcon_top_register_gate(dev, "dsi", regs,
 198                                              &tcon_top->reg_lock,
 199                                              TCON_TOP_TCON_DSI_GATE, 2);
 200
 201         for (i = 0; i < CLK_NUM; i++)
 202                 if (IS_ERR(clk_data->hws[i])) {
 203                         ret = PTR_ERR(clk_data->hws[i]);
 204                         goto err_unregister_gates;
 205                 }
 206
 207         clk_data->num = CLK_NUM;
 208
 209         ret = of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
 210                                      clk_data);
 211         if (ret)
 212                 goto err_unregister_gates;
 213
 214         dev_set_drvdata(dev, tcon_top);
 215
 216         return 0;
 217
 218 err_unregister_gates:
 219         for (i = 0; i < CLK_NUM; i++)
 220                 if (!IS_ERR_OR_NULL(clk_data->hws[i]))
 221                         clk_hw_unregister_gate(clk_data->hws[i]);
 222         clk_disable_unprepare(tcon_top->bus);
 223 err_assert_reset:
 224         reset_control_assert(tcon_top->rst);
 225
 226         return ret;
 227 }
 228
 229 static void sun8i_tcon_top_unbind(struct device *dev, struct device *master,
 230                                   void *data)
 231 {
 232         struct sun8i_tcon_top *tcon_top = dev_get_drvdata(dev);
 233         struct clk_hw_onecell_data *clk_data = tcon_top->clk_data;
 234         int i;
 235
 236         of_clk_del_provider(dev->of_node);
 237         for (i = 0; i < CLK_NUM; i++)
 238                 if (clk_data->hws[i])
 239                         clk_hw_unregister_gate(clk_data->hws[i]);
 240
 241         clk_disable_unprepare(tcon_top->bus);
 242         reset_control_assert(tcon_top->rst);
 243 }
 244
 245 static const struct component_ops sun8i_tcon_top_ops = {
 246         .bind   = sun8i_tcon_top_bind,
 247         .unbind = sun8i_tcon_top_unbind,
 248 };
 249
 250 static int sun8i_tcon_top_probe(struct platform_device *pdev)
 251 {
 252         return component_add(&pdev->dev, &sun8i_tcon_top_ops);
 253 }
 254
 255 static int sun8i_tcon_top_remove(struct platform_device *pdev)
 256 {
 257         component_del(&pdev->dev, &sun8i_tcon_top_ops);
 258
 259         return 0;
 260 }
 261
 262 /* sun4i_drv uses this list to check if a device node is a TCON TOP */
 263 const struct of_device_id sun8i_tcon_top_of_table[] = {
 264         { /* sentinel */ }
 265 };
 266 MODULE_DEVICE_TABLE(of, sun8i_tcon_top_of_table);
 267 EXPORT_SYMBOL(sun8i_tcon_top_of_table);
 268
 269 static struct platform_driver sun8i_tcon_top_platform_driver = {
 270         .probe          = sun8i_tcon_top_probe,
 271         .remove         = sun8i_tcon_top_remove,
 272         .driver         = {
 273                 .name           = "sun8i-tcon-top",
 274                 .of_match_table = sun8i_tcon_top_of_table,
 275         },
 276 };
 277 module_platform_driver(sun8i_tcon_top_platform_driver);
 278
 279 MODULE_AUTHOR("Jernej Skrabec <jernej.skrabec@siol.net>");
 280 MODULE_DESCRIPTION("Allwinner R40 TCON TOP driver");
 281 MODULE_LICENSE("GPL");