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 = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate, 91 info); 92 if (ret) 93 dev_err(dev, "could not register acpi_dma_controller\n"); 94 } 95 #else /* !CONFIG_ACPI */ 96 static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {} 97 #endif /* !CONFIG_ACPI */ 98 99 #ifdef CONFIG_OF 100 static struct dw_dma_platform_data * 101 dw_dma_parse_dt(struct platform_device *pdev) 102 { 103 struct device_node *np = pdev->dev.of_node; 104 struct dw_dma_platform_data *pdata; 105 u32 tmp, arr[DW_DMA_MAX_NR_MASTERS]; 106 107 if (!np) { 108 dev_err(&pdev->dev, "Missing DT data\n"); 109 return NULL; 110 } 111 112 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 113 if (!pdata) 114 return NULL; 115 116 if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels)) 117 return NULL; 118 119 if (of_property_read_bool(np, "is_private")) 120 pdata->is_private = true; 121 122 if (!of_property_read_u32(np, "chan_allocation_order", &tmp)) 123 pdata->chan_allocation_order = (unsigned char)tmp; 124 125 if (!of_property_read_u32(np, "chan_priority", &tmp)) 126 pdata->chan_priority = tmp; 127 128 if (!of_property_read_u32(np, "block_size", &tmp)) 129 pdata->block_size = tmp; 130 131 if (!of_property_read_u32(np, "dma-masters", &tmp)) { 132 if (tmp > DW_DMA_MAX_NR_MASTERS) 133 return NULL; 134 135 pdata->nr_masters = tmp; 136 } 137 138 if (!of_property_read_u32_array(np, "data_width", arr, 139 pdata->nr_masters)) 140 for (tmp = 0; tmp < pdata->nr_masters; tmp++) 141 pdata->data_width[tmp] = arr[tmp]; 142 143 return pdata; 144 } 145 #else 146 static inline struct dw_dma_platform_data * 147 dw_dma_parse_dt(struct platform_device *pdev) 148 { 149 return NULL; 150 } 151 #endif 152 153 static int dw_probe(struct platform_device *pdev) 154 { 155 struct dw_dma_chip *chip; 156 struct device *dev = &pdev->dev; 157 struct resource *mem; 158 struct dw_dma_platform_data *pdata; 159 int err; 160 161 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); 162 if (!chip) 163 return -ENOMEM; 164 165 chip->irq = platform_get_irq(pdev, 0); 166 if (chip->irq < 0) 167 return chip->irq; 168 169 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 170 chip->regs = devm_ioremap_resource(dev, mem); 171 if (IS_ERR(chip->regs)) 172 return PTR_ERR(chip->regs); 173 174 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); 175 if (err) 176 return err; 177 178 pdata = dev_get_platdata(dev); 179 if (!pdata) 180 pdata = dw_dma_parse_dt(pdev); 181 182 chip->dev = dev; 183 184 chip->clk = devm_clk_get(chip->dev, "hclk"); 185 if (IS_ERR(chip->clk)) 186 return PTR_ERR(chip->clk); 187 err = clk_prepare_enable(chip->clk); 188 if (err) 189 return err; 190 191 pm_runtime_enable(&pdev->dev); 192 193 err = dw_dma_probe(chip, pdata); 194 if (err) 195 goto err_dw_dma_probe; 196 197 platform_set_drvdata(pdev, chip); 198 199 if (pdev->dev.of_node) { 200 err = of_dma_controller_register(pdev->dev.of_node, 201 dw_dma_of_xlate, chip->dw); 202 if (err) 203 dev_err(&pdev->dev, 204 "could not register of_dma_controller\n"); 205 } 206 207 if (ACPI_HANDLE(&pdev->dev)) 208 dw_dma_acpi_controller_register(chip->dw); 209 210 return 0; 211 212 err_dw_dma_probe: 213 pm_runtime_disable(&pdev->dev); 214 clk_disable_unprepare(chip->clk); 215 return err; 216 } 217 218 static int dw_remove(struct platform_device *pdev) 219 { 220 struct dw_dma_chip *chip = platform_get_drvdata(pdev); 221 222 if (pdev->dev.of_node) 223 of_dma_controller_free(pdev->dev.of_node); 224 225 dw_dma_remove(chip); 226 pm_runtime_disable(&pdev->dev); 227 clk_disable_unprepare(chip->clk); 228 229 return 0; 230 } 231 232 static void dw_shutdown(struct platform_device *pdev) 233 { 234 struct dw_dma_chip *chip = platform_get_drvdata(pdev); 235 236 dw_dma_disable(chip); 237 clk_disable_unprepare(chip->clk); 238 } 239 240 #ifdef CONFIG_OF 241 static const struct of_device_id dw_dma_of_id_table[] = { 242 { .compatible = "snps,dma-spear1340" }, 243 {} 244 }; 245 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table); 246 #endif 247 248 #ifdef CONFIG_ACPI 249 static const struct acpi_device_id dw_dma_acpi_id_table[] = { 250 { "INTL9C60", 0 }, 251 { } 252 }; 253 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table); 254 #endif 255 256 #ifdef CONFIG_PM_SLEEP 257 258 static int dw_suspend_late(struct device *dev) 259 { 260 struct platform_device *pdev = to_platform_device(dev); 261 struct dw_dma_chip *chip = platform_get_drvdata(pdev); 262 263 dw_dma_disable(chip); 264 clk_disable_unprepare(chip->clk); 265 266 return 0; 267 } 268 269 static int dw_resume_early(struct device *dev) 270 { 271 struct platform_device *pdev = to_platform_device(dev); 272 struct dw_dma_chip *chip = platform_get_drvdata(pdev); 273 274 clk_prepare_enable(chip->clk); 275 return dw_dma_enable(chip); 276 } 277 278 #endif /* CONFIG_PM_SLEEP */ 279 280 static const struct dev_pm_ops dw_dev_pm_ops = { 281 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early) 282 }; 283 284 static struct platform_driver dw_driver = { 285 .probe = dw_probe, 286 .remove = dw_remove, 287 .shutdown = dw_shutdown, 288 .driver = { 289 .name = DRV_NAME, 290 .pm = &dw_dev_pm_ops, 291 .of_match_table = of_match_ptr(dw_dma_of_id_table), 292 .acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table), 293 }, 294 }; 295 296 static int __init dw_init(void) 297 { 298 return platform_driver_register(&dw_driver); 299 } 300 subsys_initcall(dw_init); 301 302 static void __exit dw_exit(void) 303 { 304 platform_driver_unregister(&dw_driver); 305 } 306 module_exit(dw_exit); 307 308 MODULE_LICENSE("GPL v2"); 309 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver"); 310 MODULE_ALIAS("platform:" DRV_NAME); 311