+ tf->device |= ATA_LBA;
+ } else {
+ /* CHS */
+ u32 sect, head, cyl, track;
+
+ /* The request -may- be too large for CHS addressing. */
+ if ((block >> 28) || (n_block > 256))
+ return 1;
+
+ /* Convert LBA to CHS */
+ track = (u32)block / dev->sectors;
+ cyl = track / dev->heads;
+ head = track % dev->heads;
+ sect = (u32)block % dev->sectors + 1;
+
+ DPRINTK("block[%u] track[%u] cyl[%u] head[%u] sect[%u] \n",
+ (u32)block, track, cyl, head, sect);
+
+ /* Check whether the converted CHS can fit.
+ Cylinder: 0-65535
+ Head: 0-15
+ Sector: 1-255*/
+ if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
+ return 1;
+
+ qc->nsect = n_block;
+ tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
+ tf->lbal = sect;
+ tf->lbam = cyl;
+ tf->lbah = cyl >> 8;
+ tf->device |= head;