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