1 /* 2 * Driver for EHCI HCD on SPEAR SOC 3 * 4 * Copyright (C) 2010 ST Micro Electronics, 5 * Deepak Sikri <deepak.sikri@st.com> 6 * 7 * Based on various ehci-*.c drivers 8 * 9 * This file is subject to the terms and conditions of the GNU General Public 10 * License. See the file COPYING in the main directory of this archive for 11 * more details. 12 */ 13 14 #include <linux/clk.h> 15 #include <linux/jiffies.h> 16 #include <linux/of.h> 17 #include <linux/platform_device.h> 18 #include <linux/pm.h> 19 20 struct spear_ehci { 21 struct ehci_hcd ehci; 22 struct clk *clk; 23 }; 24 25 #define to_spear_ehci(hcd) (struct spear_ehci *)hcd_to_ehci(hcd) 26 27 static void spear_start_ehci(struct spear_ehci *ehci) 28 { 29 clk_prepare_enable(ehci->clk); 30 } 31 32 static void spear_stop_ehci(struct spear_ehci *ehci) 33 { 34 clk_disable_unprepare(ehci->clk); 35 } 36 37 static int ehci_spear_setup(struct usb_hcd *hcd) 38 { 39 struct ehci_hcd *ehci = hcd_to_ehci(hcd); 40 int retval = 0; 41 42 /* registers start at offset 0x0 */ 43 ehci->caps = hcd->regs; 44 ehci->regs = hcd->regs + HC_LENGTH(ehci, ehci_readl(ehci, 45 &ehci->caps->hc_capbase)); 46 /* cache this readonly data; minimize chip reads */ 47 ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params); 48 retval = ehci_halt(ehci); 49 if (retval) 50 return retval; 51 52 retval = ehci_init(hcd); 53 if (retval) 54 return retval; 55 56 ehci_reset(ehci); 57 ehci_port_power(ehci, 0); 58 59 return retval; 60 } 61 62 static const struct hc_driver ehci_spear_hc_driver = { 63 .description = hcd_name, 64 .product_desc = "SPEAr EHCI", 65 .hcd_priv_size = sizeof(struct spear_ehci), 66 67 /* generic hardware linkage */ 68 .irq = ehci_irq, 69 .flags = HCD_MEMORY | HCD_USB2, 70 71 /* basic lifecycle operations */ 72 .reset = ehci_spear_setup, 73 .start = ehci_run, 74 .stop = ehci_stop, 75 .shutdown = ehci_shutdown, 76 77 /* managing i/o requests and associated device resources */ 78 .urb_enqueue = ehci_urb_enqueue, 79 .urb_dequeue = ehci_urb_dequeue, 80 .endpoint_disable = ehci_endpoint_disable, 81 .endpoint_reset = ehci_endpoint_reset, 82 83 /* scheduling support */ 84 .get_frame_number = ehci_get_frame, 85 86 /* root hub support */ 87 .hub_status_data = ehci_hub_status_data, 88 .hub_control = ehci_hub_control, 89 .bus_suspend = ehci_bus_suspend, 90 .bus_resume = ehci_bus_resume, 91 .relinquish_port = ehci_relinquish_port, 92 .port_handed_over = ehci_port_handed_over, 93 .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete, 94 }; 95 96 #ifdef CONFIG_PM 97 static int ehci_spear_drv_suspend(struct device *dev) 98 { 99 struct usb_hcd *hcd = dev_get_drvdata(dev); 100 struct ehci_hcd *ehci = hcd_to_ehci(hcd); 101 unsigned long flags; 102 int rc = 0; 103 104 if (time_before(jiffies, ehci->next_statechange)) 105 msleep(10); 106 107 /* 108 * Root hub was already suspended. Disable irq emission and mark HW 109 * unaccessible. The PM and USB cores make sure that the root hub is 110 * either suspended or stopped. 111 */ 112 spin_lock_irqsave(&ehci->lock, flags); 113 ehci_prepare_ports_for_controller_suspend(ehci, device_may_wakeup(dev)); 114 ehci_writel(ehci, 0, &ehci->regs->intr_enable); 115 ehci_readl(ehci, &ehci->regs->intr_enable); 116 spin_unlock_irqrestore(&ehci->lock, flags); 117 118 return rc; 119 } 120 121 static int ehci_spear_drv_resume(struct device *dev) 122 { 123 struct usb_hcd *hcd = dev_get_drvdata(dev); 124 struct ehci_hcd *ehci = hcd_to_ehci(hcd); 125 126 if (time_before(jiffies, ehci->next_statechange)) 127 msleep(100); 128 129 if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF) { 130 int mask = INTR_MASK; 131 132 ehci_prepare_ports_for_controller_resume(ehci); 133 134 if (!hcd->self.root_hub->do_remote_wakeup) 135 mask &= ~STS_PCD; 136 137 ehci_writel(ehci, mask, &ehci->regs->intr_enable); 138 ehci_readl(ehci, &ehci->regs->intr_enable); 139 return 0; 140 } 141 142 usb_root_hub_lost_power(hcd->self.root_hub); 143 144 /* 145 * Else reset, to cope with power loss or flush-to-storage style 146 * "resume" having let BIOS kick in during reboot. 147 */ 148 ehci_halt(ehci); 149 ehci_reset(ehci); 150 151 /* emptying the schedule aborts any urbs */ 152 spin_lock_irq(&ehci->lock); 153 if (ehci->reclaim) 154 end_unlink_async(ehci); 155 156 ehci_work(ehci); 157 spin_unlock_irq(&ehci->lock); 158 159 ehci_writel(ehci, ehci->command, &ehci->regs->command); 160 ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag); 161 ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */ 162 163 /* here we "know" root ports should always stay powered */ 164 ehci_port_power(ehci, 1); 165 return 0; 166 } 167 #endif /* CONFIG_PM */ 168 169 static SIMPLE_DEV_PM_OPS(ehci_spear_pm_ops, ehci_spear_drv_suspend, 170 ehci_spear_drv_resume); 171 172 static u64 spear_ehci_dma_mask = DMA_BIT_MASK(32); 173 174 static int spear_ehci_hcd_drv_probe(struct platform_device *pdev) 175 { 176 struct usb_hcd *hcd ; 177 struct spear_ehci *ehci; 178 struct resource *res; 179 struct clk *usbh_clk; 180 const struct hc_driver *driver = &ehci_spear_hc_driver; 181 int irq, retval; 182 char clk_name[20] = "usbh_clk"; 183 static int instance = -1; 184 185 if (usb_disabled()) 186 return -ENODEV; 187 188 irq = platform_get_irq(pdev, 0); 189 if (irq < 0) { 190 retval = irq; 191 goto fail_irq_get; 192 } 193 194 /* 195 * Right now device-tree probed devices don't get dma_mask set. 196 * Since shared usb code relies on it, set it here for now. 197 * Once we have dma capability bindings this can go away. 198 */ 199 if (!pdev->dev.dma_mask) 200 pdev->dev.dma_mask = &spear_ehci_dma_mask; 201 202 /* 203 * Increment the device instance, when probing via device-tree 204 */ 205 if (pdev->id < 0) 206 instance++; 207 else 208 instance = pdev->id; 209 sprintf(clk_name, "usbh.%01d_clk", instance); 210 211 usbh_clk = clk_get(NULL, clk_name); 212 if (IS_ERR(usbh_clk)) { 213 dev_err(&pdev->dev, "Error getting interface clock\n"); 214 retval = PTR_ERR(usbh_clk); 215 goto fail_get_usbh_clk; 216 } 217 218 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev)); 219 if (!hcd) { 220 retval = -ENOMEM; 221 goto fail_create_hcd; 222 } 223 224 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 225 if (!res) { 226 retval = -ENODEV; 227 goto fail_request_resource; 228 } 229 230 hcd->rsrc_start = res->start; 231 hcd->rsrc_len = resource_size(res); 232 if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, 233 driver->description)) { 234 retval = -EBUSY; 235 goto fail_request_resource; 236 } 237 238 hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len); 239 if (hcd->regs == NULL) { 240 dev_dbg(&pdev->dev, "error mapping memory\n"); 241 retval = -ENOMEM; 242 goto fail_ioremap; 243 } 244 245 ehci = (struct spear_ehci *)hcd_to_ehci(hcd); 246 ehci->clk = usbh_clk; 247 248 spear_start_ehci(ehci); 249 retval = usb_add_hcd(hcd, irq, IRQF_SHARED); 250 if (retval) 251 goto fail_add_hcd; 252 253 return retval; 254 255 fail_add_hcd: 256 spear_stop_ehci(ehci); 257 iounmap(hcd->regs); 258 fail_ioremap: 259 release_mem_region(hcd->rsrc_start, hcd->rsrc_len); 260 fail_request_resource: 261 usb_put_hcd(hcd); 262 fail_create_hcd: 263 clk_put(usbh_clk); 264 fail_get_usbh_clk: 265 fail_irq_get: 266 dev_err(&pdev->dev, "init fail, %d\n", retval); 267 268 return retval ; 269 } 270 271 static int spear_ehci_hcd_drv_remove(struct platform_device *pdev) 272 { 273 struct usb_hcd *hcd = platform_get_drvdata(pdev); 274 struct spear_ehci *ehci_p = to_spear_ehci(hcd); 275 276 if (!hcd) 277 return 0; 278 if (in_interrupt()) 279 BUG(); 280 usb_remove_hcd(hcd); 281 282 if (ehci_p->clk) 283 spear_stop_ehci(ehci_p); 284 iounmap(hcd->regs); 285 release_mem_region(hcd->rsrc_start, hcd->rsrc_len); 286 usb_put_hcd(hcd); 287 288 if (ehci_p->clk) 289 clk_put(ehci_p->clk); 290 291 return 0; 292 } 293 294 static struct of_device_id spear_ehci_id_table[] __devinitdata = { 295 { .compatible = "st,spear600-ehci", }, 296 { }, 297 }; 298 299 static struct platform_driver spear_ehci_hcd_driver = { 300 .probe = spear_ehci_hcd_drv_probe, 301 .remove = spear_ehci_hcd_drv_remove, 302 .shutdown = usb_hcd_platform_shutdown, 303 .driver = { 304 .name = "spear-ehci", 305 .bus = &platform_bus_type, 306 .pm = &ehci_spear_pm_ops, 307 .of_match_table = of_match_ptr(spear_ehci_id_table), 308 } 309 }; 310 311 MODULE_ALIAS("platform:spear-ehci"); 312