+/*
+ * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise
+ */
+static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
+ int *busw)
+{
+ struct nand_onfi_params *p = &chip->onfi_params;
+ int i;
+ int val;
+
+ /* try ONFI for unknow chip or LP */
+ chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);
+ if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||
+ chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I')
+ return 0;
+
+ MTDDEBUG(MTD_DEBUG_LEVEL0, "ONFI flash detected\n");
+ chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
+ for (i = 0; i < 3; i++) {
+ chip->read_buf(mtd, (uint8_t *)p, sizeof(*p));
+ if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==
+ le16_to_cpu(p->crc)) {
+ MTDDEBUG(MTD_DEBUG_LEVEL0,
+ "ONFI param page %d valid\n", i);
+ break;
+ }
+ }
+
+ if (i == 3)
+ return 0;
+
+ /* check version */
+ val = le16_to_cpu(p->revision);
+ if (val & (1 << 5))
+ chip->onfi_version = 23;
+ else if (val & (1 << 4))
+ chip->onfi_version = 22;
+ else if (val & (1 << 3))
+ chip->onfi_version = 21;
+ else if (val & (1 << 2))
+ chip->onfi_version = 20;
+ else if (val & (1 << 1))
+ chip->onfi_version = 10;
+ else
+ chip->onfi_version = 0;
+
+ if (!chip->onfi_version) {
+ printk(KERN_INFO "%s: unsupported ONFI version: %d\n",
+ __func__, val);
+ return 0;
+ }
+
+ sanitize_string(p->manufacturer, sizeof(p->manufacturer));
+ sanitize_string(p->model, sizeof(p->model));
+ if (!mtd->name)
+ mtd->name = p->model;
+ mtd->writesize = le32_to_cpu(p->byte_per_page);
+ mtd->erasesize = le32_to_cpu(p->pages_per_block) * mtd->writesize;
+ mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
+ chip->chipsize = (uint64_t)le32_to_cpu(p->blocks_per_lun) * mtd->erasesize;
+ *busw = 0;
+ if (le16_to_cpu(p->features) & 1)
+ *busw = NAND_BUSWIDTH_16;
+
+ chip->options &= ~NAND_CHIPOPTIONS_MSK;
+ chip->options |= (NAND_NO_READRDY |
+ NAND_NO_AUTOINCR) & NAND_CHIPOPTIONS_MSK;
+
+ return 1;
+}
+#else
+static inline int nand_flash_detect_onfi(struct mtd_info *mtd,
+ struct nand_chip *chip,
+ int *busw)
+{
+ return 0;
+}
+#endif
+