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"); 303