drivers/dma/dw/platform.c

   1 /*
   2  * Platform driver for the Synopsys DesignWare DMA Controller
   3  *
   4  * Copyright (C) 2007-2008 Atmel Corporation
   5  * Copyright (C) 2010-2011 ST Microelectronics
   6  * Copyright (C) 2013 Intel Corporation
   7  *
   8  * Some parts of this driver are derived from the original dw_dmac.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/device.h>
  17 #include <linux/clk.h>
  18 #include <linux/pm_runtime.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/dmaengine.h>
  21 #include <linux/dma-mapping.h>
  22 #include <linux/of.h>
  23 #include <linux/of_dma.h>
  24 #include <linux/acpi.h>
  25 #include <linux/acpi_dma.h>
  26
  27 #include "internal.h"
  28
  29 #define DRV_NAME        "dw_dmac"
  30
  31 static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
  32                                         struct of_dma *ofdma)
  33 {
  34         struct dw_dma *dw = ofdma->of_dma_data;
  35         struct dw_dma_slave slave = {
  36                 .dma_dev = dw->dma.dev,
  37         };
  38         dma_cap_mask_t cap;
  39
  40         if (dma_spec->args_count != 3)
  41                 return NULL;
  42
  43         slave.src_id = dma_spec->args[0];
  44         slave.dst_id = dma_spec->args[0];
  45         slave.src_master = dma_spec->args[1];
  46         slave.dst_master = dma_spec->args[2];
  47
  48         if (WARN_ON(slave.src_id >= DW_DMA_MAX_NR_REQUESTS ||
  49                     slave.dst_id >= DW_DMA_MAX_NR_REQUESTS ||
  50                     slave.src_master >= dw->nr_masters ||
  51                     slave.dst_master >= dw->nr_masters))
  52                 return NULL;
  53
  54         dma_cap_zero(cap);
  55         dma_cap_set(DMA_SLAVE, cap);
  56
  57         /* TODO: there should be a simpler way to do this */
  58         return dma_request_channel(cap, dw_dma_filter, &slave);
  59 }
  60
  61 #ifdef CONFIG_ACPI
  62 static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
  63 {
  64         struct acpi_dma_spec *dma_spec = param;
  65         struct dw_dma_slave slave = {
  66                 .dma_dev = dma_spec->dev,
  67                 .src_id = dma_spec->slave_id,
  68                 .dst_id = dma_spec->slave_id,
  69                 .src_master = 1,
  70                 .dst_master = 0,
  71         };
  72
  73         return dw_dma_filter(chan, &slave);
  74 }
  75
  76 static void dw_dma_acpi_controller_register(struct dw_dma *dw)
  77 {
  78         struct device *dev = dw->dma.dev;
  79         struct acpi_dma_filter_info *info;
  80         int ret;
  81
  82         info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
  83         if (!info)
  84                 return;
  85
  86         dma_cap_zero(info->dma_cap);
  87         dma_cap_set(DMA_SLAVE, info->dma_cap);
  88         info->filter_fn = dw_dma_acpi_filter;
  89
  90         ret = acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info);
  91         if (ret)
  92                 dev_err(dev, "could not register acpi_dma_controller\n");
  93 }
  94
  95 static void dw_dma_acpi_controller_free(struct dw_dma *dw)
  96 {
  97         struct device *dev = dw->dma.dev;
  98
  99         acpi_dma_controller_free(dev);
 100 }
 101 #else /* !CONFIG_ACPI */
 102 static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
 103 static inline void dw_dma_acpi_controller_free(struct dw_dma *dw) {}
 104 #endif /* !CONFIG_ACPI */
 105
 106 #ifdef CONFIG_OF
 107 static struct dw_dma_platform_data *
 108 dw_dma_parse_dt(struct platform_device *pdev)
 109 {
 110         struct device_node *np = pdev->dev.of_node;
 111         struct dw_dma_platform_data *pdata;
 112         u32 tmp, arr[DW_DMA_MAX_NR_MASTERS];
 113
 114         if (!np) {
 115                 dev_err(&pdev->dev, "Missing DT data\n");
 116                 return NULL;
 117         }
 118
 119         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 120         if (!pdata)
 121                 return NULL;
 122
 123         if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels))
 124                 return NULL;
 125
 126         if (of_property_read_bool(np, "is_private"))
 127                 pdata->is_private = true;
 128
 129         if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
 130                 pdata->chan_allocation_order = (unsigned char)tmp;
 131
 132         if (!of_property_read_u32(np, "chan_priority", &tmp))
 133                 pdata->chan_priority = tmp;
 134
 135         if (!of_property_read_u32(np, "block_size", &tmp))
 136                 pdata->block_size = tmp;
 137
 138         if (!of_property_read_u32(np, "dma-masters", &tmp)) {
 139                 if (tmp > DW_DMA_MAX_NR_MASTERS)
 140                         return NULL;
 141
 142                 pdata->nr_masters = tmp;
 143         }
 144
 145         if (!of_property_read_u32_array(np, "data_width", arr,
 146                                 pdata->nr_masters))
 147                 for (tmp = 0; tmp < pdata->nr_masters; tmp++)
 148                         pdata->data_width[tmp] = arr[tmp];
 149
 150         return pdata;
 151 }
 152 #else
 153 static inline struct dw_dma_platform_data *
 154 dw_dma_parse_dt(struct platform_device *pdev)
 155 {
 156         return NULL;
 157 }
 158 #endif
 159
 160 static int dw_probe(struct platform_device *pdev)
 161 {
 162         struct dw_dma_chip *chip;
 163         struct device *dev = &pdev->dev;
 164         struct resource *mem;
 165         const struct acpi_device_id *id;
 166         struct dw_dma_platform_data *pdata;
 167         int err;
 168
 169         chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 170         if (!chip)
 171                 return -ENOMEM;
 172
 173         chip->irq = platform_get_irq(pdev, 0);
 174         if (chip->irq < 0)
 175                 return chip->irq;
 176
 177         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 178         chip->regs = devm_ioremap_resource(dev, mem);
 179         if (IS_ERR(chip->regs))
 180                 return PTR_ERR(chip->regs);
 181
 182         err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 183         if (err)
 184                 return err;
 185
 186         pdata = dev_get_platdata(dev);
 187         if (!pdata)
 188                 pdata = dw_dma_parse_dt(pdev);
 189         if (!pdata && has_acpi_companion(dev)) {
 190                 id = acpi_match_device(dev->driver->acpi_match_table, dev);
 191                 if (id)
 192                         pdata = (struct dw_dma_platform_data *)id->driver_data;
 193         }
 194
 195         chip->dev = dev;
 196
 197         chip->clk = devm_clk_get(chip->dev, "hclk");
 198         if (IS_ERR(chip->clk))
 199                 return PTR_ERR(chip->clk);
 200         err = clk_prepare_enable(chip->clk);
 201         if (err)
 202                 return err;
 203
 204         pm_runtime_enable(&pdev->dev);
 205
 206         err = dw_dma_probe(chip, pdata);
 207         if (err)
 208                 goto err_dw_dma_probe;
 209
 210         platform_set_drvdata(pdev, chip);
 211
 212         if (pdev->dev.of_node) {
 213                 err = of_dma_controller_register(pdev->dev.of_node,
 214                                                  dw_dma_of_xlate, chip->dw);
 215                 if (err)
 216                         dev_err(&pdev->dev,
 217                                 "could not register of_dma_controller\n");
 218         }
 219
 220         if (ACPI_HANDLE(&pdev->dev))
 221                 dw_dma_acpi_controller_register(chip->dw);
 222
 223         return 0;
 224
 225 err_dw_dma_probe:
 226         pm_runtime_disable(&pdev->dev);
 227         clk_disable_unprepare(chip->clk);
 228         return err;
 229 }
 230
 231 static int dw_remove(struct platform_device *pdev)
 232 {
 233         struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 234
 235         if (ACPI_HANDLE(&pdev->dev))
 236                 dw_dma_acpi_controller_free(chip->dw);
 237
 238         if (pdev->dev.of_node)
 239                 of_dma_controller_free(pdev->dev.of_node);
 240
 241         dw_dma_remove(chip);
 242         pm_runtime_disable(&pdev->dev);
 243         clk_disable_unprepare(chip->clk);
 244
 245         return 0;
 246 }
 247
 248 static void dw_shutdown(struct platform_device *pdev)
 249 {
 250         struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 251
 252         dw_dma_disable(chip);
 253         clk_disable_unprepare(chip->clk);
 254 }
 255
 256 #ifdef CONFIG_OF
 257 static const struct of_device_id dw_dma_of_id_table[] = {
 258         { .compatible = "snps,dma-spear1340" },
 259         {}
 260 };
 261 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
 262 #endif
 263
 264 #ifdef CONFIG_ACPI
 265 static struct dw_dma_platform_data dw_dma_acpi_pdata = {
 266         .nr_channels = 8,
 267         .is_private = true,
 268         .chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
 269         .chan_priority = CHAN_PRIORITY_ASCENDING,
 270         .block_size = 4095,
 271         .nr_masters = 2,
 272 };
 273
 274 static const struct acpi_device_id dw_dma_acpi_id_table[] = {
 275         { "INTL9C60", (kernel_ulong_t)&dw_dma_acpi_pdata },
 276         { }
 277 };
 278 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
 279 #endif
 280
 281 #ifdef CONFIG_PM_SLEEP
 282
 283 static int dw_suspend_late(struct device *dev)
 284 {
 285         struct platform_device *pdev = to_platform_device(dev);
 286         struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 287
 288         dw_dma_disable(chip);
 289         clk_disable_unprepare(chip->clk);
 290
 291         return 0;
 292 }
 293
 294 static int dw_resume_early(struct device *dev)
 295 {
 296         struct platform_device *pdev = to_platform_device(dev);
 297         struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 298
 299         clk_prepare_enable(chip->clk);
 300         return dw_dma_enable(chip);
 301 }
 302
 303 #endif /* CONFIG_PM_SLEEP */
 304
 305 static const struct dev_pm_ops dw_dev_pm_ops = {
 306         SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
 307 };
 308
 309 static struct platform_driver dw_driver = {
 310         .probe          = dw_probe,
 311         .remove         = dw_remove,
 312         .shutdown       = dw_shutdown,
 313         .driver = {
 314                 .name   = DRV_NAME,
 315                 .pm     = &dw_dev_pm_ops,
 316                 .of_match_table = of_match_ptr(dw_dma_of_id_table),
 317                 .acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
 318         },
 319 };
 320
 321 static int __init dw_init(void)
 322 {
 323         return platform_driver_register(&dw_driver);
 324 }
 325 subsys_initcall(dw_init);
 326
 327 static void __exit dw_exit(void)
 328 {
 329         platform_driver_unregister(&dw_driver);
 330 }
 331 module_exit(dw_exit);
 332
 333 MODULE_LICENSE("GPL v2");
 334 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
 335 MODULE_ALIAS("platform:" DRV_NAME);