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-rw-r--r--Documentation/DocBook/libata.tmpl58
1 files changed, 39 insertions, 19 deletions
diff --git a/Documentation/DocBook/libata.tmpl b/Documentation/DocBook/libata.tmpl
index 773ae9fd99dc..41053aed41f4 100644
--- a/Documentation/DocBook/libata.tmpl
+++ b/Documentation/DocBook/libata.tmpl
@@ -14,7 +14,7 @@
14 </authorgroup> 14 </authorgroup>
15 15
16 <copyright> 16 <copyright>
17 <year>2003</year> 17 <year>2003-2005</year>
18 <holder>Jeff Garzik</holder> 18 <holder>Jeff Garzik</holder>
19 </copyright> 19 </copyright>
20 20
@@ -145,14 +145,25 @@ void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
145 </para> 145 </para>
146 146
147 <programlisting> 147 <programlisting>
148int (*check_atapi_dma) (struct ata_queued_cmd *qc);
149 </programlisting>
150
151 <para>
152Allow low-level driver to filter ATA PACKET commands, returning a status
153indicating whether or not it is OK to use DMA for the supplied PACKET
154command.
155 </para>
156
157 <programlisting>
148u8 (*check_status)(struct ata_port *ap); 158u8 (*check_status)(struct ata_port *ap);
149void (*dev_select)(struct ata_port *ap, unsigned int device); 159u8 (*check_altstatus)(struct ata_port *ap);
160u8 (*check_err)(struct ata_port *ap);
150 </programlisting> 161 </programlisting>
151 162
152 <para> 163 <para>
153 Reads the Status ATA shadow register from hardware. On some 164 Reads the Status/AltStatus/Error ATA shadow register from
154 hardware, this has the side effect of clearing the interrupt 165 hardware. On some hardware, reading the Status register has
155 condition. 166 the side effect of clearing the interrupt condition.
156 </para> 167 </para>
157 168
158 <programlisting> 169 <programlisting>
@@ -162,7 +173,8 @@ void (*dev_select)(struct ata_port *ap, unsigned int device);
162 <para> 173 <para>
163 Issues the low-level hardware command(s) that causes one of N 174 Issues the low-level hardware command(s) that causes one of N
164 hardware devices to be considered 'selected' (active and 175 hardware devices to be considered 'selected' (active and
165 available for use) on the ATA bus. 176 available for use) on the ATA bus. This generally has no
177meaning on FIS-based devices.
166 </para> 178 </para>
167 179
168 <programlisting> 180 <programlisting>
@@ -180,12 +192,20 @@ void (*phy_reset) (struct ata_port *ap);
180 <programlisting> 192 <programlisting>
181void (*bmdma_setup) (struct ata_queued_cmd *qc); 193void (*bmdma_setup) (struct ata_queued_cmd *qc);
182void (*bmdma_start) (struct ata_queued_cmd *qc); 194void (*bmdma_start) (struct ata_queued_cmd *qc);
195void (*bmdma_stop) (struct ata_port *ap);
196u8 (*bmdma_status) (struct ata_port *ap);
183 </programlisting> 197 </programlisting>
184 198
185 <para> 199 <para>
186 When setting up an IDE BMDMA transaction, these hooks arm 200When setting up an IDE BMDMA transaction, these hooks arm
187 (->bmdma_setup) and fire (->bmdma_start) the hardware's DMA 201(->bmdma_setup), fire (->bmdma_start), and halt (->bmdma_stop)
188 engine. 202the hardware's DMA engine. ->bmdma_status is used to read the standard
203PCI IDE DMA Status register.
204 </para>
205
206 <para>
207These hooks are typically either no-ops, or simply not implemented, in
208FIS-based drivers.
189 </para> 209 </para>
190 210
191 <programlisting> 211 <programlisting>
@@ -205,9 +225,7 @@ int (*qc_issue) (struct ata_queued_cmd *qc);
205 ->qc_issue is used to make a command active, once the hardware 225 ->qc_issue is used to make a command active, once the hardware
206 and S/G tables have been prepared. IDE BMDMA drivers use the 226 and S/G tables have been prepared. IDE BMDMA drivers use the
207 helper function ata_qc_issue_prot() for taskfile protocol-based 227 helper function ata_qc_issue_prot() for taskfile protocol-based
208 dispatch. More advanced drivers roll their own ->qc_issue 228 dispatch. More advanced drivers implement their own ->qc_issue.
209 implementation, using this as the "issue new ATA command to
210 hardware" hook.
211 </para> 229 </para>
212 230
213 <programlisting> 231 <programlisting>
@@ -215,8 +233,10 @@ void (*eng_timeout) (struct ata_port *ap);
215 </programlisting> 233 </programlisting>
216 234
217 <para> 235 <para>
218 This is a high level error handling function, called from the 236This is a high level error handling function, called from the
219 error handling thread, when a command times out. 237error handling thread, when a command times out. Most newer
238hardware will implement its own error handling code here. IDE BMDMA
239drivers may use the helper function ata_eng_timeout().
220 </para> 240 </para>
221 241
222 <programlisting> 242 <programlisting>
@@ -255,15 +275,15 @@ void (*host_stop) (struct ata_host_set *host_set);
255 tasks. 275 tasks.
256 </para> 276 </para>
257 <para> 277 <para>
258 ->host_stop() is called when the rmmod or hot unplug process
259 begins. The hook must stop all hardware interrupts, DMA
260 engines, etc.
261 </para>
262 <para>
263 ->port_stop() is called after ->host_stop(). It's sole function 278 ->port_stop() is called after ->host_stop(). It's sole function
264 is to release DMA/memory resources, now that they are no longer 279 is to release DMA/memory resources, now that they are no longer
265 actively being used. 280 actively being used.
266 </para> 281 </para>
282 <para>
283 ->host_stop() is called after all ->port_stop() calls
284have completed. The hook must finalize hardware shutdown, release DMA
285and other resources, etc.
286 </para>
267 287
268 </sect1> 288 </sect1>
269 </chapter> 289 </chapter>