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Rev | Author | Line No. | Line |
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846 | giacomo | 1 | /* |
2 | * Copyright (c) 2001-2002 by David Brownell |
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3 | * |
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4 | * This program is free software; you can redistribute it and/or modify it |
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5 | * under the terms of the GNU General Public License as published by the |
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6 | * Free Software Foundation; either version 2 of the License, or (at your |
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7 | * option) any later version. |
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8 | * |
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9 | * This program is distributed in the hope that it will be useful, but |
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10 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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11 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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12 | * for more details. |
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13 | * |
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14 | * You should have received a copy of the GNU General Public License |
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15 | * along with this program; if not, write to the Free Software Foundation, |
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16 | * Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
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17 | */ |
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18 | |||
19 | /* this file is part of ehci-hcd.c */ |
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20 | |||
21 | /*-------------------------------------------------------------------------*/ |
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22 | |||
23 | /* |
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24 | * EHCI hardware queue manipulation ... the core. QH/QTD manipulation. |
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25 | * |
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26 | * Control, bulk, and interrupt traffic all use "qh" lists. They list "qtd" |
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27 | * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned |
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28 | * buffers needed for the larger number). We use one QH per endpoint, queue |
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29 | * multiple urbs (all three types) per endpoint. URBs may need several qtds. |
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30 | * |
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31 | * ISO traffic uses "ISO TD" (itd, and sitd) records, and (along with |
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32 | * interrupts) needs careful scheduling. Performance improvements can be |
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33 | * an ongoing challenge. That's in "ehci-sched.c". |
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34 | * |
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35 | * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs, |
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36 | * or otherwise through transaction translators (TTs) in USB 2.0 hubs using |
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37 | * (b) special fields in qh entries or (c) split iso entries. TTs will |
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38 | * buffer low/full speed data so the host collects it at high speed. |
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39 | */ |
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40 | |||
41 | /*-------------------------------------------------------------------------*/ |
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42 | |||
43 | /* fill a qtd, returning how much of the buffer we were able to queue up */ |
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44 | |||
45 | static int |
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46 | qtd_fill (struct ehci_qtd *qtd, dma_addr_t buf, size_t len, |
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47 | int token, int maxpacket) |
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48 | { |
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49 | int i, count; |
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50 | u64 addr = buf; |
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51 | |||
52 | /* one buffer entry per 4K ... first might be short or unaligned */ |
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53 | qtd->hw_buf [0] = cpu_to_le32 ((u32)addr); |
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54 | qtd->hw_buf_hi [0] = cpu_to_le32 ((u32)(addr >> 32)); |
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55 | count = 0x1000 - (buf & 0x0fff); /* rest of that page */ |
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56 | if (likely (len < count)) /* ... iff needed */ |
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57 | count = len; |
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58 | else { |
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59 | buf += 0x1000; |
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60 | buf &= ~0x0fff; |
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61 | |||
62 | /* per-qtd limit: from 16K to 20K (best alignment) */ |
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63 | for (i = 1; count < len && i < 5; i++) { |
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64 | addr = buf; |
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65 | qtd->hw_buf [i] = cpu_to_le32 ((u32)addr); |
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66 | qtd->hw_buf_hi [i] = cpu_to_le32 ((u32)(addr >> 32)); |
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67 | buf += 0x1000; |
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68 | if ((count + 0x1000) < len) |
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69 | count += 0x1000; |
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70 | else |
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71 | count = len; |
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72 | } |
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73 | |||
74 | /* short packets may only terminate transfers */ |
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75 | if (count != len) |
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76 | count -= (count % maxpacket); |
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77 | } |
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78 | qtd->hw_token = cpu_to_le32 ((count << 16) | token); |
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79 | qtd->length = count; |
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80 | |||
81 | return count; |
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82 | } |
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83 | |||
84 | /*-------------------------------------------------------------------------*/ |
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85 | |||
86 | /* update halted (but potentially linked) qh */ |
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87 | |||
88 | static inline void |
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89 | qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd) |
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90 | { |
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91 | qh->hw_qtd_next = QTD_NEXT (qtd->qtd_dma); |
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92 | qh->hw_alt_next = EHCI_LIST_END; |
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93 | |||
94 | /* HC must see latest qtd and qh data before we clear ACTIVE+HALT */ |
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95 | wmb (); |
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96 | qh->hw_token &= __constant_cpu_to_le32 (QTD_TOGGLE | QTD_STS_PING); |
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97 | } |
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98 | |||
99 | /*-------------------------------------------------------------------------*/ |
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100 | |||
101 | static void qtd_copy_status ( |
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102 | struct ehci_hcd *ehci, |
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103 | struct urb *urb, |
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104 | size_t length, |
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105 | u32 token |
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106 | ) |
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107 | { |
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108 | /* count IN/OUT bytes, not SETUP (even short packets) */ |
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109 | if (likely (QTD_PID (token) != 2)) |
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110 | urb->actual_length += length - QTD_LENGTH (token); |
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111 | |||
112 | /* don't modify error codes */ |
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113 | if (unlikely (urb->status != -EINPROGRESS)) |
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114 | return; |
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115 | |||
116 | /* force cleanup after short read; not always an error */ |
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117 | if (unlikely (IS_SHORT_READ (token))) |
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118 | urb->status = -EREMOTEIO; |
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119 | |||
120 | /* serious "can't proceed" faults reported by the hardware */ |
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121 | if (token & QTD_STS_HALT) { |
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122 | if (token & QTD_STS_BABBLE) { |
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123 | /* FIXME "must" disable babbling device's port too */ |
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124 | urb->status = -EOVERFLOW; |
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125 | } else if (token & QTD_STS_MMF) { |
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126 | /* fs/ls interrupt xfer missed the complete-split */ |
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127 | urb->status = -EPROTO; |
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128 | } else if (token & QTD_STS_DBE) { |
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129 | urb->status = (QTD_PID (token) == 1) /* IN ? */ |
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130 | ? -ENOSR /* hc couldn't read data */ |
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131 | : -ECOMM; /* hc couldn't write data */ |
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132 | } else if (token & QTD_STS_XACT) { |
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133 | /* timeout, bad crc, wrong PID, etc; retried */ |
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134 | if (QTD_CERR (token)) |
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135 | urb->status = -EPIPE; |
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136 | else { |
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137 | ehci_dbg (ehci, "devpath %s ep%d%s 3strikes\n", |
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138 | urb->dev->devpath, |
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139 | usb_pipeendpoint (urb->pipe), |
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140 | usb_pipein (urb->pipe) ? "in" : "out"); |
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141 | urb->status = -EPROTO; |
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142 | } |
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143 | /* CERR nonzero + no errors + halt --> stall */ |
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144 | } else if (QTD_CERR (token)) |
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145 | urb->status = -EPIPE; |
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146 | else /* unknown */ |
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147 | urb->status = -EPROTO; |
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148 | |||
149 | ehci_vdbg (ehci, |
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150 | "dev%d ep%d%s qtd token %08x --> status %d\n", |
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151 | usb_pipedevice (urb->pipe), |
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152 | usb_pipeendpoint (urb->pipe), |
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153 | usb_pipein (urb->pipe) ? "in" : "out", |
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154 | token, urb->status); |
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155 | |||
156 | /* stall indicates some recovery action is needed */ |
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157 | if (urb->status == -EPIPE) { |
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158 | int pipe = urb->pipe; |
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159 | |||
160 | if (!usb_pipecontrol (pipe)) |
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161 | usb_endpoint_halt (urb->dev, |
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162 | usb_pipeendpoint (pipe), |
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163 | usb_pipeout (pipe)); |
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164 | |||
165 | /* if async CSPLIT failed, try cleaning out the TT buffer */ |
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166 | } else if (urb->dev->tt && !usb_pipeint (urb->pipe) |
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167 | && QTD_CERR(token) == 0) { |
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168 | #ifdef DEBUG |
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169 | struct usb_device *tt = urb->dev->tt->hub; |
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170 | dev_dbg (&tt->dev, |
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171 | "clear tt buffer port %d, a%d ep%d t%08x\n", |
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172 | urb->dev->ttport, urb->dev->devnum, |
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173 | usb_pipeendpoint (urb->pipe), token); |
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174 | #endif /* DEBUG */ |
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175 | usb_hub_tt_clear_buffer (urb->dev, urb->pipe); |
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176 | } |
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177 | } |
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178 | } |
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179 | |||
180 | static void |
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181 | ehci_urb_done (struct ehci_hcd *ehci, struct urb *urb, struct pt_regs *regs) |
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182 | { |
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183 | if (likely (urb->hcpriv != 0)) { |
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184 | struct ehci_qh *qh = (struct ehci_qh *) urb->hcpriv; |
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185 | |||
186 | /* S-mask in a QH means it's an interrupt urb */ |
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187 | if ((qh->hw_info2 & __constant_cpu_to_le32 (0x00ff)) != 0) { |
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188 | |||
189 | /* ... update hc-wide periodic stats (for usbfs) */ |
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190 | hcd_to_bus (&ehci->hcd)->bandwidth_int_reqs--; |
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191 | } |
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192 | qh_put (ehci, qh); |
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193 | } |
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194 | |||
195 | spin_lock (&urb->lock); |
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196 | urb->hcpriv = 0; |
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197 | switch (urb->status) { |
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198 | case -EINPROGRESS: /* success */ |
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199 | urb->status = 0; |
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200 | default: /* fault */ |
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201 | COUNT (ehci->stats.complete); |
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202 | break; |
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203 | case -EREMOTEIO: /* fault or normal */ |
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204 | if (!(urb->transfer_flags & URB_SHORT_NOT_OK)) |
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205 | urb->status = 0; |
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206 | COUNT (ehci->stats.complete); |
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207 | break; |
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208 | case -ECONNRESET: /* canceled */ |
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209 | case -ENOENT: |
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210 | COUNT (ehci->stats.unlink); |
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211 | break; |
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212 | } |
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213 | spin_unlock (&urb->lock); |
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214 | |||
215 | /* complete() can reenter this HCD */ |
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216 | spin_unlock (&ehci->lock); |
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217 | usb_hcd_giveback_urb (&ehci->hcd, urb, regs); |
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218 | spin_lock (&ehci->lock); |
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219 | } |
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220 | |||
221 | |||
222 | /* |
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223 | * Process and free completed qtds for a qh, returning URBs to drivers. |
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224 | * Chases up to qh->hw_current. Returns number of completions called, |
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225 | * indicating how much "real" work we did. |
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226 | */ |
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227 | #define HALT_BIT __constant_cpu_to_le32(QTD_STS_HALT) |
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228 | static unsigned |
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229 | qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs) |
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230 | { |
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231 | struct ehci_qtd *last = 0, *end = qh->dummy; |
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232 | struct list_head *entry, *tmp; |
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233 | int stopped; |
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234 | unsigned count = 0; |
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235 | int do_status = 0; |
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236 | u8 state; |
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237 | |||
238 | if (unlikely (list_empty (&qh->qtd_list))) |
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239 | return count; |
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240 | |||
241 | /* completions (or tasks on other cpus) must never clobber HALT |
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242 | * till we've gone through and cleaned everything up, even when |
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243 | * they add urbs to this qh's queue or mark them for unlinking. |
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244 | * |
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245 | * NOTE: unlinking expects to be done in queue order. |
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246 | */ |
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247 | state = qh->qh_state; |
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248 | qh->qh_state = QH_STATE_COMPLETING; |
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249 | stopped = (state == QH_STATE_IDLE); |
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250 | |||
251 | /* remove de-activated QTDs from front of queue. |
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252 | * after faults (including short reads), cleanup this urb |
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253 | * then let the queue advance. |
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254 | * if queue is stopped, handles unlinks. |
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255 | */ |
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256 | list_for_each_safe (entry, tmp, &qh->qtd_list) { |
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257 | struct ehci_qtd *qtd; |
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258 | struct urb *urb; |
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259 | u32 token = 0; |
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260 | |||
261 | qtd = list_entry (entry, struct ehci_qtd, qtd_list); |
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262 | urb = qtd->urb; |
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263 | |||
264 | /* clean up any state from previous QTD ...*/ |
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265 | if (last) { |
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266 | if (likely (last->urb != urb)) { |
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267 | ehci_urb_done (ehci, last->urb, regs); |
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268 | count++; |
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269 | } |
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270 | ehci_qtd_free (ehci, last); |
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271 | last = 0; |
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272 | } |
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273 | |||
274 | /* ignore urbs submitted during completions we reported */ |
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275 | if (qtd == end) |
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276 | break; |
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277 | |||
278 | /* hardware copies qtd out of qh overlay */ |
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279 | rmb (); |
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280 | token = le32_to_cpu (qtd->hw_token); |
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281 | |||
282 | /* always clean up qtds the hc de-activated */ |
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283 | if ((token & QTD_STS_ACTIVE) == 0) { |
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284 | |||
285 | if ((token & QTD_STS_HALT) != 0) { |
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286 | stopped = 1; |
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287 | |||
288 | /* magic dummy for some short reads; qh won't advance */ |
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289 | } else if (IS_SHORT_READ (token) |
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290 | && (qh->hw_alt_next & QTD_MASK) |
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291 | == ehci->async->hw_alt_next) { |
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292 | stopped = 1; |
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293 | goto halt; |
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294 | } |
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295 | |||
296 | /* stop scanning when we reach qtds the hc is using */ |
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297 | } else if (likely (!stopped |
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298 | && HCD_IS_RUNNING (ehci->hcd.state))) { |
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299 | break; |
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300 | |||
301 | } else { |
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302 | stopped = 1; |
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303 | |||
304 | /* ignore active urbs unless some previous qtd |
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305 | * for the urb faulted (including short read) or |
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306 | * its urb was canceled. we may patch qh or qtds. |
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307 | */ |
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308 | if (likely (urb->status == -EINPROGRESS)) |
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309 | continue; |
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310 | |||
311 | /* issue status after short control reads */ |
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312 | if (unlikely (do_status != 0) |
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313 | && QTD_PID (token) == 0 /* OUT */) { |
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314 | do_status = 0; |
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315 | continue; |
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316 | } |
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317 | |||
318 | /* token in overlay may be most current */ |
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319 | if (state == QH_STATE_IDLE |
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320 | && cpu_to_le32 (qtd->qtd_dma) |
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321 | == qh->hw_current) |
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322 | token = le32_to_cpu (qh->hw_token); |
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323 | |||
324 | /* force halt for unlinked or blocked qh, so we'll |
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325 | * patch the qh later and so that completions can't |
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326 | * activate it while we "know" it's stopped. |
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327 | */ |
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328 | if ((HALT_BIT & qh->hw_token) == 0) { |
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329 | halt: |
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330 | qh->hw_token |= HALT_BIT; |
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331 | wmb (); |
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332 | } |
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333 | } |
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334 | |||
335 | /* remove it from the queue */ |
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336 | spin_lock (&urb->lock); |
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337 | qtd_copy_status (ehci, urb, qtd->length, token); |
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338 | do_status = (urb->status == -EREMOTEIO) |
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339 | && usb_pipecontrol (urb->pipe); |
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340 | spin_unlock (&urb->lock); |
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341 | |||
342 | if (stopped && qtd->qtd_list.prev != &qh->qtd_list) { |
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343 | last = list_entry (qtd->qtd_list.prev, |
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344 | struct ehci_qtd, qtd_list); |
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345 | last->hw_next = qtd->hw_next; |
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346 | } |
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347 | list_del (&qtd->qtd_list); |
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348 | last = qtd; |
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349 | } |
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350 | |||
351 | /* last urb's completion might still need calling */ |
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352 | if (likely (last != 0)) { |
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353 | ehci_urb_done (ehci, last->urb, regs); |
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354 | count++; |
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355 | ehci_qtd_free (ehci, last); |
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356 | } |
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357 | |||
358 | /* restore original state; caller must unlink or relink */ |
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359 | qh->qh_state = state; |
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360 | |||
361 | /* update qh after fault cleanup */ |
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362 | if (unlikely (stopped != 0) |
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363 | /* some EHCI 0.95 impls will overlay dummy qtds */ |
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364 | || qh->hw_qtd_next == EHCI_LIST_END) { |
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365 | if (list_empty (&qh->qtd_list)) |
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366 | end = qh->dummy; |
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367 | else { |
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368 | end = list_entry (qh->qtd_list.next, |
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369 | struct ehci_qtd, qtd_list); |
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370 | /* first qtd may already be partially processed */ |
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371 | if (cpu_to_le32 (end->qtd_dma) == qh->hw_current) |
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372 | end = 0; |
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373 | } |
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374 | if (end) |
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375 | qh_update (ehci, qh, end); |
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376 | } |
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377 | |||
378 | return count; |
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379 | } |
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380 | |||
381 | /*-------------------------------------------------------------------------*/ |
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382 | |||
383 | // high bandwidth multiplier, as encoded in highspeed endpoint descriptors |
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384 | #define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03)) |
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385 | // ... and packet size, for any kind of endpoint descriptor |
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386 | #define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff) |
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387 | |||
388 | /* |
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389 | * reverse of qh_urb_transaction: free a list of TDs. |
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390 | * used for cleanup after errors, before HC sees an URB's TDs. |
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391 | */ |
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392 | static void qtd_list_free ( |
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393 | struct ehci_hcd *ehci, |
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394 | struct urb *urb, |
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395 | struct list_head *qtd_list |
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396 | ) { |
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397 | struct list_head *entry, *temp; |
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398 | |||
399 | list_for_each_safe (entry, temp, qtd_list) { |
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400 | struct ehci_qtd *qtd; |
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401 | |||
402 | qtd = list_entry (entry, struct ehci_qtd, qtd_list); |
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403 | list_del (&qtd->qtd_list); |
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404 | ehci_qtd_free (ehci, qtd); |
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405 | } |
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406 | } |
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407 | |||
408 | /* |
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409 | * create a list of filled qtds for this URB; won't link into qh. |
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410 | */ |
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411 | static struct list_head * |
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412 | qh_urb_transaction ( |
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413 | struct ehci_hcd *ehci, |
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414 | struct urb *urb, |
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415 | struct list_head *head, |
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416 | int flags |
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417 | ) { |
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418 | struct ehci_qtd *qtd, *qtd_prev; |
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419 | dma_addr_t buf; |
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420 | int len, maxpacket; |
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421 | int is_input; |
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422 | u32 token; |
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423 | |||
424 | /* |
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425 | * URBs map to sequences of QTDs: one logical transaction |
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426 | */ |
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427 | qtd = ehci_qtd_alloc (ehci, flags); |
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428 | if (unlikely (!qtd)) |
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429 | return 0; |
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430 | list_add_tail (&qtd->qtd_list, head); |
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431 | qtd->urb = urb; |
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432 | |||
433 | token = QTD_STS_ACTIVE; |
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434 | token |= (EHCI_TUNE_CERR << 10); |
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435 | /* for split transactions, SplitXState initialized to zero */ |
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436 | |||
437 | len = urb->transfer_buffer_length; |
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438 | is_input = usb_pipein (urb->pipe); |
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439 | if (usb_pipecontrol (urb->pipe)) { |
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440 | /* SETUP pid */ |
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441 | qtd_fill (qtd, urb->setup_dma, sizeof (struct usb_ctrlrequest), |
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442 | token | (2 /* "setup" */ << 8), 8); |
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443 | |||
444 | /* ... and always at least one more pid */ |
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445 | token ^= QTD_TOGGLE; |
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446 | qtd_prev = qtd; |
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447 | qtd = ehci_qtd_alloc (ehci, flags); |
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448 | if (unlikely (!qtd)) |
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449 | goto cleanup; |
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450 | qtd->urb = urb; |
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451 | qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma); |
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452 | list_add_tail (&qtd->qtd_list, head); |
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453 | } |
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454 | |||
455 | /* |
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456 | * data transfer stage: buffer setup |
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457 | */ |
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458 | if (likely (len > 0)) |
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459 | buf = urb->transfer_dma; |
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460 | else |
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461 | buf = 0; |
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462 | |||
463 | // FIXME this 'buf' check break some zlps... |
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464 | if (!buf || is_input) |
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465 | token |= (1 /* "in" */ << 8); |
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466 | /* else it's already initted to "out" pid (0 << 8) */ |
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467 | |||
468 | maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input)); |
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469 | |||
470 | /* |
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471 | * buffer gets wrapped in one or more qtds; |
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472 | * last one may be "short" (including zero len) |
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473 | * and may serve as a control status ack |
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474 | */ |
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475 | for (;;) { |
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476 | int this_qtd_len; |
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477 | |||
478 | this_qtd_len = qtd_fill (qtd, buf, len, token, maxpacket); |
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479 | len -= this_qtd_len; |
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480 | buf += this_qtd_len; |
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481 | if (is_input) |
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482 | qtd->hw_alt_next = ehci->async->hw_alt_next; |
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483 | |||
484 | /* qh makes control packets use qtd toggle; maybe switch it */ |
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485 | if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0) |
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486 | token ^= QTD_TOGGLE; |
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487 | |||
488 | if (likely (len <= 0)) |
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489 | break; |
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490 | |||
491 | qtd_prev = qtd; |
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492 | qtd = ehci_qtd_alloc (ehci, flags); |
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493 | if (unlikely (!qtd)) |
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494 | goto cleanup; |
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495 | qtd->urb = urb; |
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496 | qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma); |
||
497 | list_add_tail (&qtd->qtd_list, head); |
||
498 | } |
||
499 | |||
500 | /* unless the bulk/interrupt caller wants a chance to clean |
||
501 | * up after short reads, hc should advance qh past this urb |
||
502 | */ |
||
503 | if (likely ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0 |
||
504 | || usb_pipecontrol (urb->pipe))) |
||
505 | qtd->hw_alt_next = EHCI_LIST_END; |
||
506 | |||
507 | /* |
||
508 | * control requests may need a terminating data "status" ack; |
||
509 | * bulk ones may need a terminating short packet (zero length). |
||
510 | */ |
||
511 | if (likely (buf != 0)) { |
||
512 | int one_more = 0; |
||
513 | |||
514 | if (usb_pipecontrol (urb->pipe)) { |
||
515 | one_more = 1; |
||
516 | token ^= 0x0100; /* "in" <--> "out" */ |
||
517 | token |= QTD_TOGGLE; /* force DATA1 */ |
||
518 | } else if (usb_pipebulk (urb->pipe) |
||
519 | && (urb->transfer_flags & URB_ZERO_PACKET) |
||
520 | && !(urb->transfer_buffer_length % maxpacket)) { |
||
521 | one_more = 1; |
||
522 | } |
||
523 | if (one_more) { |
||
524 | qtd_prev = qtd; |
||
525 | qtd = ehci_qtd_alloc (ehci, flags); |
||
526 | if (unlikely (!qtd)) |
||
527 | goto cleanup; |
||
528 | qtd->urb = urb; |
||
529 | qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma); |
||
530 | list_add_tail (&qtd->qtd_list, head); |
||
531 | |||
532 | /* never any data in such packets */ |
||
533 | qtd_fill (qtd, 0, 0, token, 0); |
||
534 | } |
||
535 | } |
||
536 | |||
537 | /* by default, enable interrupt on urb completion */ |
||
538 | if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT))) |
||
539 | qtd->hw_token |= __constant_cpu_to_le32 (QTD_IOC); |
||
540 | return head; |
||
541 | |||
542 | cleanup: |
||
543 | qtd_list_free (ehci, urb, head); |
||
544 | return 0; |
||
545 | } |
||
546 | |||
547 | /*-------------------------------------------------------------------------*/ |
||
548 | |||
549 | /* |
||
550 | * Hardware maintains data toggle (like OHCI) ... here we (re)initialize |
||
551 | * the hardware data toggle in the QH, and set the pseudo-toggle in udev |
||
552 | * so we can see if usb_clear_halt() was called. NOP for control, since |
||
553 | * we set up qh->hw_info1 to always use the QTD toggle bits. |
||
554 | */ |
||
555 | static inline void |
||
556 | clear_toggle (struct usb_device *udev, int ep, int is_out, struct ehci_qh *qh) |
||
557 | { |
||
558 | vdbg ("clear toggle, dev %d ep 0x%x-%s", |
||
559 | udev->devnum, ep, is_out ? "out" : "in"); |
||
560 | qh->hw_token &= ~__constant_cpu_to_le32 (QTD_TOGGLE); |
||
561 | usb_settoggle (udev, ep, is_out, 1); |
||
562 | } |
||
563 | |||
564 | // Would be best to create all qh's from config descriptors, |
||
565 | // when each interface/altsetting is established. Unlink |
||
566 | // any previous qh and cancel its urbs first; endpoints are |
||
567 | // implicitly reset then (data toggle too). |
||
568 | // That'd mean updating how usbcore talks to HCDs. (2.5?) |
||
569 | |||
570 | |||
571 | /* |
||
572 | * Each QH holds a qtd list; a QH is used for everything except iso. |
||
573 | * |
||
574 | * For interrupt urbs, the scheduler must set the microframe scheduling |
||
575 | * mask(s) each time the QH gets scheduled. For highspeed, that's |
||
576 | * just one microframe in the s-mask. For split interrupt transactions |
||
577 | * there are additional complications: c-mask, maybe FSTNs. |
||
578 | */ |
||
579 | static struct ehci_qh * |
||
580 | qh_make ( |
||
581 | struct ehci_hcd *ehci, |
||
582 | struct urb *urb, |
||
583 | int flags |
||
584 | ) { |
||
585 | struct ehci_qh *qh = ehci_qh_alloc (ehci, flags); |
||
586 | u32 info1 = 0, info2 = 0; |
||
587 | int is_input, type; |
||
588 | int maxp = 0; |
||
589 | |||
590 | if (!qh) |
||
591 | return qh; |
||
592 | |||
593 | /* |
||
594 | * init endpoint/device data for this QH |
||
595 | */ |
||
596 | info1 |= usb_pipeendpoint (urb->pipe) << 8; |
||
597 | info1 |= usb_pipedevice (urb->pipe) << 0; |
||
598 | |||
599 | is_input = usb_pipein (urb->pipe); |
||
600 | type = usb_pipetype (urb->pipe); |
||
601 | maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input); |
||
602 | |||
603 | /* Compute interrupt scheduling parameters just once, and save. |
||
604 | * - allowing for high bandwidth, how many nsec/uframe are used? |
||
605 | * - split transactions need a second CSPLIT uframe; same question |
||
606 | * - splits also need a schedule gap (for full/low speed I/O) |
||
607 | * - qh has a polling interval |
||
608 | * |
||
609 | * For control/bulk requests, the HC or TT handles these. |
||
610 | */ |
||
611 | if (type == PIPE_INTERRUPT) { |
||
612 | qh->usecs = usb_calc_bus_time (USB_SPEED_HIGH, is_input, 0, |
||
613 | hb_mult (maxp) * max_packet (maxp)); |
||
614 | qh->start = NO_FRAME; |
||
615 | |||
616 | if (urb->dev->speed == USB_SPEED_HIGH) { |
||
617 | qh->c_usecs = 0; |
||
618 | qh->gap_uf = 0; |
||
619 | |||
620 | /* FIXME handle HS periods of less than 1 frame. */ |
||
621 | qh->period = urb->interval >> 3; |
||
622 | if (qh->period < 1) { |
||
623 | dbg ("intr period %d uframes, NYET!", |
||
624 | urb->interval); |
||
625 | goto done; |
||
626 | } |
||
627 | } else { |
||
628 | /* gap is f(FS/LS transfer times) */ |
||
629 | qh->gap_uf = 1 + usb_calc_bus_time (urb->dev->speed, |
||
630 | is_input, 0, maxp) / (125 * 1000); |
||
631 | |||
632 | /* FIXME this just approximates SPLIT/CSPLIT times */ |
||
633 | if (is_input) { // SPLIT, gap, CSPLIT+DATA |
||
634 | qh->c_usecs = qh->usecs + HS_USECS (0); |
||
635 | qh->usecs = HS_USECS (1); |
||
636 | } else { // SPLIT+DATA, gap, CSPLIT |
||
637 | qh->usecs += HS_USECS (1); |
||
638 | qh->c_usecs = HS_USECS (0); |
||
639 | } |
||
640 | |||
641 | qh->period = urb->interval; |
||
642 | } |
||
643 | } |
||
644 | |||
645 | /* using TT? */ |
||
646 | switch (urb->dev->speed) { |
||
647 | case USB_SPEED_LOW: |
||
648 | info1 |= (1 << 12); /* EPS "low" */ |
||
649 | /* FALL THROUGH */ |
||
650 | |||
651 | case USB_SPEED_FULL: |
||
652 | /* EPS 0 means "full" */ |
||
653 | if (type != PIPE_INTERRUPT) |
||
654 | info1 |= (EHCI_TUNE_RL_TT << 28); |
||
655 | if (type == PIPE_CONTROL) { |
||
656 | info1 |= (1 << 27); /* for TT */ |
||
657 | info1 |= 1 << 14; /* toggle from qtd */ |
||
658 | } |
||
659 | info1 |= maxp << 16; |
||
660 | |||
661 | info2 |= (EHCI_TUNE_MULT_TT << 30); |
||
662 | info2 |= urb->dev->ttport << 23; |
||
663 | info2 |= urb->dev->tt->hub->devnum << 16; |
||
664 | |||
665 | /* NOTE: if (PIPE_INTERRUPT) { scheduler sets c-mask } */ |
||
666 | |||
667 | break; |
||
668 | |||
669 | case USB_SPEED_HIGH: /* no TT involved */ |
||
670 | info1 |= (2 << 12); /* EPS "high" */ |
||
671 | if (type == PIPE_CONTROL) { |
||
672 | info1 |= (EHCI_TUNE_RL_HS << 28); |
||
673 | info1 |= 64 << 16; /* usb2 fixed maxpacket */ |
||
674 | info1 |= 1 << 14; /* toggle from qtd */ |
||
675 | info2 |= (EHCI_TUNE_MULT_HS << 30); |
||
676 | } else if (type == PIPE_BULK) { |
||
677 | info1 |= (EHCI_TUNE_RL_HS << 28); |
||
678 | info1 |= 512 << 16; /* usb2 fixed maxpacket */ |
||
679 | info2 |= (EHCI_TUNE_MULT_HS << 30); |
||
680 | } else { /* PIPE_INTERRUPT */ |
||
681 | info1 |= max_packet (maxp) << 16; |
||
682 | info2 |= hb_mult (maxp) << 30; |
||
683 | } |
||
684 | break; |
||
685 | default: |
||
686 | dbg ("bogus dev %p speed %d", urb->dev, urb->dev->speed); |
||
687 | done: |
||
688 | qh_put (ehci, qh); |
||
689 | return 0; |
||
690 | } |
||
691 | |||
692 | /* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */ |
||
693 | |||
694 | /* init as live, toggle clear, advance to dummy */ |
||
695 | qh->qh_state = QH_STATE_IDLE; |
||
696 | qh->hw_info1 = cpu_to_le32 (info1); |
||
697 | qh->hw_info2 = cpu_to_le32 (info2); |
||
698 | qh_update (ehci, qh, qh->dummy); |
||
699 | usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1); |
||
700 | return qh; |
||
701 | } |
||
702 | #undef hb_mult |
||
703 | #undef hb_packet |
||
704 | |||
705 | /*-------------------------------------------------------------------------*/ |
||
706 | |||
707 | /* move qh (and its qtds) onto async queue; maybe enable queue. */ |
||
708 | |||
709 | static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh) |
||
710 | { |
||
711 | u32 dma = QH_NEXT (qh->qh_dma); |
||
712 | struct ehci_qh *head; |
||
713 | |||
714 | /* (re)start the async schedule? */ |
||
715 | head = ehci->async; |
||
716 | timer_action_done (ehci, TIMER_ASYNC_OFF); |
||
717 | if (!head->qh_next.qh) { |
||
718 | u32 cmd = readl (&ehci->regs->command); |
||
719 | |||
720 | if (!(cmd & CMD_ASE)) { |
||
721 | /* in case a clear of CMD_ASE didn't take yet */ |
||
722 | (void) handshake (&ehci->regs->status, STS_ASS, 0, 150); |
||
723 | cmd |= CMD_ASE | CMD_RUN; |
||
724 | writel (cmd, &ehci->regs->command); |
||
725 | ehci->hcd.state = USB_STATE_RUNNING; |
||
726 | /* posted write need not be known to HC yet ... */ |
||
727 | } |
||
728 | } |
||
729 | |||
730 | qh->hw_token &= ~HALT_BIT; |
||
731 | |||
732 | /* splice right after start */ |
||
733 | qh->qh_next = head->qh_next; |
||
734 | qh->hw_next = head->hw_next; |
||
735 | wmb (); |
||
736 | |||
737 | head->qh_next.qh = qh; |
||
738 | head->hw_next = dma; |
||
739 | |||
740 | qh->qh_state = QH_STATE_LINKED; |
||
741 | /* qtd completions reported later by interrupt */ |
||
742 | } |
||
743 | |||
744 | /*-------------------------------------------------------------------------*/ |
||
745 | |||
746 | #define QH_ADDR_MASK __constant_le32_to_cpu(0x7f) |
||
747 | |||
748 | /* |
||
749 | * For control/bulk/interrupt, return QH with these TDs appended. |
||
750 | * Allocates and initializes the QH if necessary. |
||
751 | * Returns null if it can't allocate a QH it needs to. |
||
752 | * If the QH has TDs (urbs) already, that's great. |
||
753 | */ |
||
754 | static struct ehci_qh *qh_append_tds ( |
||
755 | struct ehci_hcd *ehci, |
||
756 | struct urb *urb, |
||
757 | struct list_head *qtd_list, |
||
758 | int epnum, |
||
759 | void **ptr |
||
760 | ) |
||
761 | { |
||
762 | struct ehci_qh *qh = 0; |
||
763 | |||
764 | qh = (struct ehci_qh *) *ptr; |
||
765 | if (unlikely (qh == 0)) { |
||
766 | /* can't sleep here, we have ehci->lock... */ |
||
767 | qh = qh_make (ehci, urb, SLAB_ATOMIC); |
||
768 | *ptr = qh; |
||
769 | } |
||
770 | if (likely (qh != 0)) { |
||
771 | struct ehci_qtd *qtd; |
||
772 | |||
773 | if (unlikely (list_empty (qtd_list))) |
||
774 | qtd = 0; |
||
775 | else |
||
776 | qtd = list_entry (qtd_list->next, struct ehci_qtd, |
||
777 | qtd_list); |
||
778 | |||
779 | /* control qh may need patching after enumeration */ |
||
780 | if (unlikely (epnum == 0)) { |
||
781 | /* set_address changes the address */ |
||
782 | if ((qh->hw_info1 & QH_ADDR_MASK) == 0) |
||
783 | qh->hw_info1 |= cpu_to_le32 ( |
||
784 | usb_pipedevice (urb->pipe)); |
||
785 | |||
786 | /* for full speed, ep0 maxpacket can grow */ |
||
787 | else if (!(qh->hw_info1 |
||
788 | & __constant_cpu_to_le32 (0x3 << 12))) { |
||
789 | u32 info, max; |
||
790 | |||
791 | info = le32_to_cpu (qh->hw_info1); |
||
792 | max = urb->dev->descriptor.bMaxPacketSize0; |
||
793 | if (max > (0x07ff & (info >> 16))) { |
||
794 | info &= ~(0x07ff << 16); |
||
795 | info |= max << 16; |
||
796 | qh->hw_info1 = cpu_to_le32 (info); |
||
797 | } |
||
798 | } |
||
799 | |||
800 | /* usb_reset_device() briefly reverts to address 0 */ |
||
801 | if (usb_pipedevice (urb->pipe) == 0) |
||
802 | qh->hw_info1 &= ~QH_ADDR_MASK; |
||
803 | } |
||
804 | |||
805 | /* usb_clear_halt() means qh data toggle gets reset */ |
||
806 | if (unlikely (!usb_gettoggle (urb->dev, |
||
807 | (epnum & 0x0f), !(epnum & 0x10))) |
||
808 | && !usb_pipecontrol (urb->pipe)) { |
||
809 | /* "never happens": drivers do stall cleanup right */ |
||
810 | if (qh->qh_state != QH_STATE_IDLE |
||
811 | && !list_empty (&qh->qtd_list) |
||
812 | && qh->qh_state != QH_STATE_COMPLETING) |
||
813 | ehci_warn (ehci, "clear toggle dev%d " |
||
814 | "ep%d%s: not idle\n", |
||
815 | usb_pipedevice (urb->pipe), |
||
816 | epnum & 0x0f, |
||
817 | usb_pipein (urb->pipe) |
||
818 | ? "in" : "out"); |
||
819 | /* else we know this overlay write is safe */ |
||
820 | clear_toggle (urb->dev, |
||
821 | epnum & 0x0f, !(epnum & 0x10), qh); |
||
822 | } |
||
823 | |||
824 | /* just one way to queue requests: swap with the dummy qtd. |
||
825 | * only hc or qh_completions() usually modify the overlay. |
||
826 | */ |
||
827 | if (likely (qtd != 0)) { |
||
828 | struct ehci_qtd *dummy; |
||
829 | dma_addr_t dma; |
||
830 | u32 token; |
||
831 | |||
832 | /* to avoid racing the HC, use the dummy td instead of |
||
833 | * the first td of our list (becomes new dummy). both |
||
834 | * tds stay deactivated until we're done, when the |
||
835 | * HC is allowed to fetch the old dummy (4.10.2). |
||
836 | */ |
||
837 | token = qtd->hw_token; |
||
838 | qtd->hw_token = HALT_BIT; |
||
839 | wmb (); |
||
840 | dummy = qh->dummy; |
||
841 | |||
842 | dma = dummy->qtd_dma; |
||
843 | *dummy = *qtd; |
||
844 | dummy->qtd_dma = dma; |
||
845 | |||
846 | list_del (&qtd->qtd_list); |
||
847 | list_add (&dummy->qtd_list, qtd_list); |
||
848 | __list_splice (qtd_list, qh->qtd_list.prev); |
||
849 | |||
850 | ehci_qtd_init (qtd, qtd->qtd_dma); |
||
851 | qh->dummy = qtd; |
||
852 | |||
853 | /* hc must see the new dummy at list end */ |
||
854 | dma = qtd->qtd_dma; |
||
855 | qtd = list_entry (qh->qtd_list.prev, |
||
856 | struct ehci_qtd, qtd_list); |
||
857 | qtd->hw_next = QTD_NEXT (dma); |
||
858 | |||
859 | /* let the hc process these next qtds */ |
||
860 | wmb (); |
||
861 | dummy->hw_token = token; |
||
862 | |||
863 | urb->hcpriv = qh_get (qh); |
||
864 | } |
||
865 | } |
||
866 | return qh; |
||
867 | } |
||
868 | |||
869 | /*-------------------------------------------------------------------------*/ |
||
870 | |||
871 | static int |
||
872 | submit_async ( |
||
873 | struct ehci_hcd *ehci, |
||
874 | struct urb *urb, |
||
875 | struct list_head *qtd_list, |
||
876 | int mem_flags |
||
877 | ) { |
||
878 | struct ehci_qtd *qtd; |
||
879 | struct hcd_dev *dev; |
||
880 | int epnum; |
||
881 | unsigned long flags; |
||
882 | struct ehci_qh *qh = 0; |
||
883 | |||
884 | qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list); |
||
885 | dev = (struct hcd_dev *)urb->dev->hcpriv; |
||
886 | epnum = usb_pipeendpoint (urb->pipe); |
||
887 | if (usb_pipein (urb->pipe) && !usb_pipecontrol (urb->pipe)) |
||
888 | epnum |= 0x10; |
||
889 | |||
890 | ehci_vdbg (ehci, "submit_async urb %p len %d ep%d%s qtd %p [qh %p]\n", |
||
891 | urb, urb->transfer_buffer_length, |
||
892 | epnum & 0x0f, (epnum & 0x10) ? "in" : "out", |
||
893 | qtd, dev ? dev->ep [epnum] : (void *)~0); |
||
894 | |||
895 | spin_lock_irqsave (&ehci->lock, flags); |
||
896 | qh = qh_append_tds (ehci, urb, qtd_list, epnum, &dev->ep [epnum]); |
||
897 | |||
898 | /* Control/bulk operations through TTs don't need scheduling, |
||
899 | * the HC and TT handle it when the TT has a buffer ready. |
||
900 | */ |
||
901 | if (likely (qh != 0)) { |
||
902 | if (likely (qh->qh_state == QH_STATE_IDLE)) |
||
903 | qh_link_async (ehci, qh_get (qh)); |
||
904 | } |
||
905 | spin_unlock_irqrestore (&ehci->lock, flags); |
||
906 | if (unlikely (qh == 0)) { |
||
907 | qtd_list_free (ehci, urb, qtd_list); |
||
908 | return -ENOMEM; |
||
909 | } |
||
910 | return 0; |
||
911 | } |
||
912 | |||
913 | /*-------------------------------------------------------------------------*/ |
||
914 | |||
915 | /* the async qh for the qtds being reclaimed are now unlinked from the HC */ |
||
916 | |||
917 | static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh); |
||
918 | |||
919 | static void end_unlink_async (struct ehci_hcd *ehci, struct pt_regs *regs) |
||
920 | { |
||
921 | struct ehci_qh *qh = ehci->reclaim; |
||
922 | struct ehci_qh *next; |
||
923 | |||
924 | timer_action_done (ehci, TIMER_IAA_WATCHDOG); |
||
925 | |||
926 | // qh->hw_next = cpu_to_le32 (qh->qh_dma); |
||
927 | qh->qh_state = QH_STATE_IDLE; |
||
928 | qh->qh_next.qh = 0; |
||
929 | qh_put (ehci, qh); // refcount from reclaim |
||
930 | |||
931 | /* other unlink(s) may be pending (in QH_STATE_UNLINK_WAIT) */ |
||
932 | next = qh->reclaim; |
||
933 | ehci->reclaim = next; |
||
934 | ehci->reclaim_ready = 0; |
||
935 | qh->reclaim = 0; |
||
936 | |||
937 | qh_completions (ehci, qh, regs); |
||
938 | |||
939 | if (!list_empty (&qh->qtd_list) |
||
940 | && HCD_IS_RUNNING (ehci->hcd.state)) |
||
941 | qh_link_async (ehci, qh); |
||
942 | else { |
||
943 | qh_put (ehci, qh); // refcount from async list |
||
944 | |||
945 | /* it's not free to turn the async schedule on/off; leave it |
||
946 | * active but idle for a while once it empties. |
||
947 | */ |
||
948 | if (HCD_IS_RUNNING (ehci->hcd.state) |
||
949 | && ehci->async->qh_next.qh == 0) |
||
950 | timer_action (ehci, TIMER_ASYNC_OFF); |
||
951 | } |
||
952 | |||
953 | if (next) { |
||
954 | ehci->reclaim = 0; |
||
955 | start_unlink_async (ehci, next); |
||
956 | } |
||
957 | } |
||
958 | |||
959 | /* makes sure the async qh will become idle */ |
||
960 | /* caller must own ehci->lock */ |
||
961 | |||
962 | static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh) |
||
963 | { |
||
964 | int cmd = readl (&ehci->regs->command); |
||
965 | struct ehci_qh *prev; |
||
966 | |||
967 | #ifdef DEBUG |
||
968 | if (ehci->reclaim |
||
969 | || (qh->qh_state != QH_STATE_LINKED |
||
970 | && qh->qh_state != QH_STATE_UNLINK_WAIT) |
||
971 | #ifdef CONFIG_SMP |
||
972 | // this macro lies except on SMP compiles |
||
973 | || !spin_is_locked (&ehci->lock) |
||
974 | #endif |
||
975 | ) |
||
976 | BUG (); |
||
977 | #endif |
||
978 | |||
979 | /* stop async schedule right now? */ |
||
980 | if (unlikely (qh == ehci->async)) { |
||
981 | /* can't get here without STS_ASS set */ |
||
982 | if (ehci->hcd.state != USB_STATE_HALT) { |
||
983 | writel (cmd & ~CMD_ASE, &ehci->regs->command); |
||
984 | wmb (); |
||
985 | // handshake later, if we need to |
||
986 | } |
||
987 | timer_action_done (ehci, TIMER_ASYNC_OFF); |
||
988 | return; |
||
989 | } |
||
990 | |||
991 | qh->qh_state = QH_STATE_UNLINK; |
||
992 | ehci->reclaim = qh = qh_get (qh); |
||
993 | |||
994 | prev = ehci->async; |
||
995 | while (prev->qh_next.qh != qh) |
||
996 | prev = prev->qh_next.qh; |
||
997 | |||
998 | prev->hw_next = qh->hw_next; |
||
999 | prev->qh_next = qh->qh_next; |
||
1000 | wmb (); |
||
1001 | |||
1002 | if (unlikely (ehci->hcd.state == USB_STATE_HALT)) { |
||
1003 | /* if (unlikely (qh->reclaim != 0)) |
||
1004 | * this will recurse, probably not much |
||
1005 | */ |
||
1006 | end_unlink_async (ehci, NULL); |
||
1007 | return; |
||
1008 | } |
||
1009 | |||
1010 | ehci->reclaim_ready = 0; |
||
1011 | cmd |= CMD_IAAD; |
||
1012 | writel (cmd, &ehci->regs->command); |
||
1013 | (void) readl (&ehci->regs->command); |
||
1014 | timer_action (ehci, TIMER_IAA_WATCHDOG); |
||
1015 | } |
||
1016 | |||
1017 | /*-------------------------------------------------------------------------*/ |
||
1018 | |||
1019 | static void |
||
1020 | scan_async (struct ehci_hcd *ehci, struct pt_regs *regs) |
||
1021 | { |
||
1022 | struct ehci_qh *qh; |
||
1023 | enum ehci_timer_action action = TIMER_IO_WATCHDOG; |
||
1024 | |||
1025 | if (!++(ehci->stamp)) |
||
1026 | ehci->stamp++; |
||
1027 | timer_action_done (ehci, TIMER_ASYNC_SHRINK); |
||
1028 | rescan: |
||
1029 | qh = ehci->async->qh_next.qh; |
||
1030 | if (likely (qh != 0)) { |
||
1031 | do { |
||
1032 | /* clean any finished work for this qh */ |
||
1033 | if (!list_empty (&qh->qtd_list) |
||
1034 | && qh->stamp != ehci->stamp) { |
||
1035 | int temp; |
||
1036 | |||
1037 | /* unlinks could happen here; completion |
||
1038 | * reporting drops the lock. rescan using |
||
1039 | * the latest schedule, but don't rescan |
||
1040 | * qhs we already finished (no looping). |
||
1041 | */ |
||
1042 | qh = qh_get (qh); |
||
1043 | qh->stamp = ehci->stamp; |
||
1044 | temp = qh_completions (ehci, qh, regs); |
||
1045 | qh_put (ehci, qh); |
||
1046 | if (temp != 0) { |
||
1047 | goto rescan; |
||
1048 | } |
||
1049 | } |
||
1050 | |||
1051 | /* unlink idle entries, reducing HC PCI usage as well |
||
1052 | * as HCD schedule-scanning costs. delay for any qh |
||
1053 | * we just scanned, there's a not-unusual case that it |
||
1054 | * doesn't stay idle for long. |
||
1055 | * (plus, avoids some kind of re-activation race.) |
||
1056 | */ |
||
1057 | if (list_empty (&qh->qtd_list)) { |
||
1058 | if (qh->stamp == ehci->stamp) |
||
1059 | action = TIMER_ASYNC_SHRINK; |
||
1060 | else if (!ehci->reclaim |
||
1061 | && qh->qh_state == QH_STATE_LINKED) |
||
1062 | start_unlink_async (ehci, qh); |
||
1063 | } |
||
1064 | |||
1065 | qh = qh->qh_next.qh; |
||
1066 | } while (qh); |
||
1067 | } |
||
1068 | if (action == TIMER_ASYNC_SHRINK) |
||
1069 | timer_action (ehci, TIMER_ASYNC_SHRINK); |
||
1070 | } |