1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget 4 * 5 * core.c - Top level support 6 * 7 * Copyright 2017 IBM Corporation 8 */ 9 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/platform_device.h> 13 #include <linux/delay.h> 14 #include <linux/ioport.h> 15 #include <linux/slab.h> 16 #include <linux/errno.h> 17 #include <linux/list.h> 18 #include <linux/interrupt.h> 19 #include <linux/proc_fs.h> 20 #include <linux/prefetch.h> 21 #include <linux/clk.h> 22 #include <linux/usb/gadget.h> 23 #include <linux/of.h> 24 #include <linux/regmap.h> 25 #include <linux/dma-mapping.h> 26 27 #include "vhub.h" 28 29 void ast_vhub_done(struct ast_vhub_ep *ep, struct ast_vhub_req *req, 30 int status) 31 { 32 bool internal = req->internal; 33 struct ast_vhub *vhub = ep->vhub; 34 35 EPVDBG(ep, "completing request @%p, status %d\n", req, status); 36 37 list_del_init(&req->queue); 38 39 if ((req->req.status == -EINPROGRESS) || (status == -EOVERFLOW)) 40 req->req.status = status; 41 42 if (req->req.dma) { 43 if (!WARN_ON(!ep->dev)) 44 usb_gadget_unmap_request_by_dev(&vhub->pdev->dev, 45 &req->req, ep->epn.is_in); 46 req->req.dma = 0; 47 } 48 49 /* 50 * If this isn't an internal EP0 request, call the core 51 * to call the gadget completion. 52 */ 53 if (!internal) { 54 spin_unlock(&ep->vhub->lock); 55 usb_gadget_giveback_request(&ep->ep, &req->req); 56 spin_lock(&ep->vhub->lock); 57 } 58 } 59 60 void ast_vhub_nuke(struct ast_vhub_ep *ep, int status) 61 { 62 struct ast_vhub_req *req; 63 int count = 0; 64 65 /* Beware, lock will be dropped & req-acquired by done() */ 66 while (!list_empty(&ep->queue)) { 67 req = list_first_entry(&ep->queue, struct ast_vhub_req, queue); 68 ast_vhub_done(ep, req, status); 69 count++; 70 } 71 if (count) 72 EPDBG(ep, "Nuked %d request(s)\n", count); 73 } 74 75 struct usb_request *ast_vhub_alloc_request(struct usb_ep *u_ep, 76 gfp_t gfp_flags) 77 { 78 struct ast_vhub_req *req; 79 80 req = kzalloc(sizeof(*req), gfp_flags); 81 if (!req) 82 return NULL; 83 return &req->req; 84 } 85 86 void ast_vhub_free_request(struct usb_ep *u_ep, struct usb_request *u_req) 87 { 88 struct ast_vhub_req *req = to_ast_req(u_req); 89 90 kfree(req); 91 } 92 93 static irqreturn_t ast_vhub_irq(int irq, void *data) 94 { 95 struct ast_vhub *vhub = data; 96 irqreturn_t iret = IRQ_NONE; 97 u32 i, istat; 98 99 /* Stale interrupt while tearing down */ 100 if (!vhub->ep0_bufs) 101 return IRQ_NONE; 102 103 spin_lock(&vhub->lock); 104 105 /* Read and ACK interrupts */ 106 istat = readl(vhub->regs + AST_VHUB_ISR); 107 if (!istat) 108 goto bail; 109 writel(istat, vhub->regs + AST_VHUB_ISR); 110 iret = IRQ_HANDLED; 111 112 UDCVDBG(vhub, "irq status=%08x, ep_acks=%08x ep_nacks=%08x\n", 113 istat, 114 readl(vhub->regs + AST_VHUB_EP_ACK_ISR), 115 readl(vhub->regs + AST_VHUB_EP_NACK_ISR)); 116 117 /* Handle generic EPs first */ 118 if (istat & VHUB_IRQ_EP_POOL_ACK_STALL) { 119 u32 ep_acks = readl(vhub->regs + AST_VHUB_EP_ACK_ISR); 120 writel(ep_acks, vhub->regs + AST_VHUB_EP_ACK_ISR); 121 122 for (i = 0; ep_acks && i < vhub->max_epns; i++) { 123 u32 mask = VHUB_EP_IRQ(i); 124 if (ep_acks & mask) { 125 ast_vhub_epn_ack_irq(&vhub->epns[i]); 126 ep_acks &= ~mask; 127 } 128 } 129 } 130 131 /* Handle device interrupts */ 132 if (istat & vhub->port_irq_mask) { 133 for (i = 0; i < vhub->max_ports; i++) { 134 if (istat & VHUB_DEV_IRQ(i)) 135 ast_vhub_dev_irq(&vhub->ports[i].dev); 136 } 137 } 138 139 /* Handle top-level vHub EP0 interrupts */ 140 if (istat & (VHUB_IRQ_HUB_EP0_OUT_ACK_STALL | 141 VHUB_IRQ_HUB_EP0_IN_ACK_STALL | 142 VHUB_IRQ_HUB_EP0_SETUP)) { 143 if (istat & VHUB_IRQ_HUB_EP0_IN_ACK_STALL) 144 ast_vhub_ep0_handle_ack(&vhub->ep0, true); 145 if (istat & VHUB_IRQ_HUB_EP0_OUT_ACK_STALL) 146 ast_vhub_ep0_handle_ack(&vhub->ep0, false); 147 if (istat & VHUB_IRQ_HUB_EP0_SETUP) 148 ast_vhub_ep0_handle_setup(&vhub->ep0); 149 } 150 151 /* Various top level bus events */ 152 if (istat & (VHUB_IRQ_BUS_RESUME | 153 VHUB_IRQ_BUS_SUSPEND | 154 VHUB_IRQ_BUS_RESET)) { 155 if (istat & VHUB_IRQ_BUS_RESUME) 156 ast_vhub_hub_resume(vhub); 157 if (istat & VHUB_IRQ_BUS_SUSPEND) 158 ast_vhub_hub_suspend(vhub); 159 if (istat & VHUB_IRQ_BUS_RESET) 160 ast_vhub_hub_reset(vhub); 161 } 162 163 bail: 164 spin_unlock(&vhub->lock); 165 return iret; 166 } 167 168 void ast_vhub_init_hw(struct ast_vhub *vhub) 169 { 170 u32 ctrl, port_mask, epn_mask; 171 172 UDCDBG(vhub,"(Re)Starting HW ...\n"); 173 174 /* Enable PHY */ 175 ctrl = VHUB_CTRL_PHY_CLK | 176 VHUB_CTRL_PHY_RESET_DIS; 177 178 /* 179 * We do *NOT* set the VHUB_CTRL_CLK_STOP_SUSPEND bit 180 * to stop the logic clock during suspend because 181 * it causes the registers to become inaccessible and 182 * we haven't yet figured out a good wayt to bring the 183 * controller back into life to issue a wakeup. 184 */ 185 186 /* 187 * Set some ISO & split control bits according to Aspeed 188 * recommendation 189 * 190 * VHUB_CTRL_ISO_RSP_CTRL: When set tells the HW to respond 191 * with 0 bytes data packet to ISO IN endpoints when no data 192 * is available. 193 * 194 * VHUB_CTRL_SPLIT_IN: This makes a SOF complete a split IN 195 * transaction. 196 */ 197 ctrl |= VHUB_CTRL_ISO_RSP_CTRL | VHUB_CTRL_SPLIT_IN; 198 writel(ctrl, vhub->regs + AST_VHUB_CTRL); 199 udelay(1); 200 201 /* Set descriptor ring size */ 202 if (AST_VHUB_DESCS_COUNT == 256) { 203 ctrl |= VHUB_CTRL_LONG_DESC; 204 writel(ctrl, vhub->regs + AST_VHUB_CTRL); 205 } else { 206 BUILD_BUG_ON(AST_VHUB_DESCS_COUNT != 32); 207 } 208 209 /* Reset all devices */ 210 port_mask = GENMASK(vhub->max_ports, 1); 211 writel(VHUB_SW_RESET_ROOT_HUB | 212 VHUB_SW_RESET_DMA_CONTROLLER | 213 VHUB_SW_RESET_EP_POOL | 214 port_mask, vhub->regs + AST_VHUB_SW_RESET); 215 udelay(1); 216 writel(0, vhub->regs + AST_VHUB_SW_RESET); 217 218 /* Disable and cleanup EP ACK/NACK interrupts */ 219 epn_mask = GENMASK(vhub->max_epns - 1, 0); 220 writel(0, vhub->regs + AST_VHUB_EP_ACK_IER); 221 writel(0, vhub->regs + AST_VHUB_EP_NACK_IER); 222 writel(epn_mask, vhub->regs + AST_VHUB_EP_ACK_ISR); 223 writel(epn_mask, vhub->regs + AST_VHUB_EP_NACK_ISR); 224 225 /* Default settings for EP0, enable HW hub EP1 */ 226 writel(0, vhub->regs + AST_VHUB_EP0_CTRL); 227 writel(VHUB_EP1_CTRL_RESET_TOGGLE | 228 VHUB_EP1_CTRL_ENABLE, 229 vhub->regs + AST_VHUB_EP1_CTRL); 230 writel(0, vhub->regs + AST_VHUB_EP1_STS_CHG); 231 232 /* Configure EP0 DMA buffer */ 233 writel(vhub->ep0.buf_dma, vhub->regs + AST_VHUB_EP0_DATA); 234 235 /* Clear address */ 236 writel(0, vhub->regs + AST_VHUB_CONF); 237 238 /* Pullup hub (activate on host) */ 239 if (vhub->force_usb1) 240 ctrl |= VHUB_CTRL_FULL_SPEED_ONLY; 241 242 ctrl |= VHUB_CTRL_UPSTREAM_CONNECT; 243 writel(ctrl, vhub->regs + AST_VHUB_CTRL); 244 245 /* Enable some interrupts */ 246 writel(VHUB_IRQ_HUB_EP0_IN_ACK_STALL | 247 VHUB_IRQ_HUB_EP0_OUT_ACK_STALL | 248 VHUB_IRQ_HUB_EP0_SETUP | 249 VHUB_IRQ_EP_POOL_ACK_STALL | 250 VHUB_IRQ_BUS_RESUME | 251 VHUB_IRQ_BUS_SUSPEND | 252 VHUB_IRQ_BUS_RESET, 253 vhub->regs + AST_VHUB_IER); 254 } 255 256 static void ast_vhub_remove(struct platform_device *pdev) 257 { 258 struct ast_vhub *vhub = platform_get_drvdata(pdev); 259 unsigned long flags; 260 int i; 261 262 if (!vhub || !vhub->regs) 263 return; 264 265 /* Remove devices */ 266 for (i = 0; i < vhub->max_ports; i++) 267 ast_vhub_del_dev(&vhub->ports[i].dev); 268 269 spin_lock_irqsave(&vhub->lock, flags); 270 271 /* Mask & ack all interrupts */ 272 writel(0, vhub->regs + AST_VHUB_IER); 273 writel(VHUB_IRQ_ACK_ALL, vhub->regs + AST_VHUB_ISR); 274 275 /* Pull device, leave PHY enabled */ 276 writel(VHUB_CTRL_PHY_CLK | 277 VHUB_CTRL_PHY_RESET_DIS, 278 vhub->regs + AST_VHUB_CTRL); 279 280 if (vhub->clk) 281 clk_disable_unprepare(vhub->clk); 282 283 spin_unlock_irqrestore(&vhub->lock, flags); 284 285 if (vhub->ep0_bufs) 286 dma_free_coherent(&pdev->dev, 287 AST_VHUB_EP0_MAX_PACKET * 288 (vhub->max_ports + 1), 289 vhub->ep0_bufs, 290 vhub->ep0_bufs_dma); 291 vhub->ep0_bufs = NULL; 292 } 293 294 static int ast_vhub_probe(struct platform_device *pdev) 295 { 296 enum usb_device_speed max_speed; 297 struct ast_vhub *vhub; 298 struct resource *res; 299 int i, rc = 0; 300 const struct device_node *np = pdev->dev.of_node; 301 302 vhub = devm_kzalloc(&pdev->dev, sizeof(*vhub), GFP_KERNEL); 303 if (!vhub) 304 return -ENOMEM; 305 306 rc = of_property_read_u32(np, "aspeed,vhub-downstream-ports", 307 &vhub->max_ports); 308 if (rc < 0) 309 vhub->max_ports = AST_VHUB_NUM_PORTS; 310 311 vhub->ports = devm_kcalloc(&pdev->dev, vhub->max_ports, 312 sizeof(*vhub->ports), GFP_KERNEL); 313 if (!vhub->ports) 314 return -ENOMEM; 315 316 rc = of_property_read_u32(np, "aspeed,vhub-generic-endpoints", 317 &vhub->max_epns); 318 if (rc < 0) 319 vhub->max_epns = AST_VHUB_NUM_GEN_EPs; 320 321 vhub->epns = devm_kcalloc(&pdev->dev, vhub->max_epns, 322 sizeof(*vhub->epns), GFP_KERNEL); 323 if (!vhub->epns) 324 return -ENOMEM; 325 326 spin_lock_init(&vhub->lock); 327 vhub->pdev = pdev; 328 vhub->port_irq_mask = GENMASK(VHUB_IRQ_DEV1_BIT + vhub->max_ports - 1, 329 VHUB_IRQ_DEV1_BIT); 330 331 vhub->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 332 if (IS_ERR(vhub->regs)) { 333 dev_err(&pdev->dev, "Failed to map resources\n"); 334 return PTR_ERR(vhub->regs); 335 } 336 UDCDBG(vhub, "vHub@%pR mapped @%p\n", res, vhub->regs); 337 338 platform_set_drvdata(pdev, vhub); 339 340 vhub->clk = devm_clk_get(&pdev->dev, NULL); 341 if (IS_ERR(vhub->clk)) { 342 rc = PTR_ERR(vhub->clk); 343 goto err; 344 } 345 rc = clk_prepare_enable(vhub->clk); 346 if (rc) { 347 dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", rc); 348 goto err; 349 } 350 351 /* Check if we need to limit the HW to USB1 */ 352 max_speed = usb_get_maximum_speed(&pdev->dev); 353 if (max_speed != USB_SPEED_UNKNOWN && max_speed < USB_SPEED_HIGH) 354 vhub->force_usb1 = true; 355 356 /* Mask & ack all interrupts before installing the handler */ 357 writel(0, vhub->regs + AST_VHUB_IER); 358 writel(VHUB_IRQ_ACK_ALL, vhub->regs + AST_VHUB_ISR); 359 360 /* Find interrupt and install handler */ 361 vhub->irq = platform_get_irq(pdev, 0); 362 if (vhub->irq < 0) { 363 rc = vhub->irq; 364 goto err; 365 } 366 rc = devm_request_irq(&pdev->dev, vhub->irq, ast_vhub_irq, 0, 367 KBUILD_MODNAME, vhub); 368 if (rc) { 369 dev_err(&pdev->dev, "Failed to request interrupt\n"); 370 goto err; 371 } 372 373 /* 374 * Allocate DMA buffers for all EP0s in one chunk, 375 * one per port and one for the vHub itself 376 */ 377 vhub->ep0_bufs = dma_alloc_coherent(&pdev->dev, 378 AST_VHUB_EP0_MAX_PACKET * 379 (vhub->max_ports + 1), 380 &vhub->ep0_bufs_dma, GFP_KERNEL); 381 if (!vhub->ep0_bufs) { 382 dev_err(&pdev->dev, "Failed to allocate EP0 DMA buffers\n"); 383 rc = -ENOMEM; 384 goto err; 385 } 386 UDCVDBG(vhub, "EP0 DMA buffers @%p (DMA 0x%08x)\n", 387 vhub->ep0_bufs, (u32)vhub->ep0_bufs_dma); 388 389 /* Init vHub EP0 */ 390 ast_vhub_init_ep0(vhub, &vhub->ep0, NULL); 391 392 /* Init devices */ 393 for (i = 0; i < vhub->max_ports && rc == 0; i++) 394 rc = ast_vhub_init_dev(vhub, i); 395 if (rc) 396 goto err; 397 398 /* Init hub emulation */ 399 rc = ast_vhub_init_hub(vhub); 400 if (rc) 401 goto err; 402 403 /* Initialize HW */ 404 ast_vhub_init_hw(vhub); 405 406 dev_info(&pdev->dev, "Initialized virtual hub in USB%d mode\n", 407 vhub->force_usb1 ? 1 : 2); 408 409 return 0; 410 err: 411 ast_vhub_remove(pdev); 412 return rc; 413 } 414 415 static const struct of_device_id ast_vhub_dt_ids[] = { 416 { 417 .compatible = "aspeed,ast2400-usb-vhub", 418 }, 419 { 420 .compatible = "aspeed,ast2500-usb-vhub", 421 }, 422 { 423 .compatible = "aspeed,ast2600-usb-vhub", 424 }, 425 { } 426 }; 427 MODULE_DEVICE_TABLE(of, ast_vhub_dt_ids); 428 429 static struct platform_driver ast_vhub_driver = { 430 .probe = ast_vhub_probe, 431 .remove_new = ast_vhub_remove, 432 .driver = { 433 .name = KBUILD_MODNAME, 434 .of_match_table = ast_vhub_dt_ids, 435 }, 436 }; 437 module_platform_driver(ast_vhub_driver); 438 439 MODULE_DESCRIPTION("Aspeed vHub udc driver"); 440 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); 441 MODULE_LICENSE("GPL"); 442