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