[PATCH v3 1/2] MXC: mxc_nand: set NFC registers after reset

[Ivo Clarysse]

This patch allows the mxc_nand driver to reset the NAND
flash controller.  NFC registers are (re-)set after
completion of the reset, as a reset will have reverted
the NFC registers to their default values.

Signed-off-by: Ivo Clarysse <ivo.clarysse at gmail.com>
---
diff -u -r -N linux-2.6.33.2/drivers/mtd/nand/mxc_nand.c
linux-2.6.33.2-reset/drivers/mtd/nand/mxc_nand.c
--- linux-2.6.33.2/drivers/mtd/nand/mxc_nand.c	2010-04-02
01:02:33.000000000 +0200
+++ linux-2.6.33.2-reset/drivers/mtd/nand/mxc_nand.c	2010-04-08
15:54:10.000000000 +0200
@@ -542,6 +542,41 @@
 	}
 }

+static void preset(struct mtd_info *mtd)
+{
+	struct nand_chip *nand_chip = mtd->priv;
+	struct mxc_nand_host *host = nand_chip->priv;
+	uint16_t tmp;
+
+	/* disable interrupt, disable spare enable */
+	tmp = readw(host->regs + NFC_CONFIG1);
+	tmp |= NFC_INT_MSK;
+	tmp &= ~NFC_SP_EN;
+	if (nand_chip->ecc.mode == NAND_ECC_HW) {
+		tmp |= NFC_ECC_EN;
+	} else {
+		tmp &= ~NFC_ECC_EN;
+	}
+	writew(tmp, host->regs + NFC_CONFIG1);
+	/* preset operation */
+
+	/* Unlock the internal RAM Buffer */
+	writew(0x2, host->regs + NFC_CONFIG);
+
+	/* Blocks to be unlocked */
+	if (nfc_is_v21()) {
+		writew(0x0, host->regs + NFC_V21_UNLOCKSTART_BLKADDR);
+		writew(0xffff, host->regs + NFC_V21_UNLOCKEND_BLKADDR);
+	} else if (nfc_is_v1()) {
+		writew(0x0, host->regs + NFC_V1_UNLOCKSTART_BLKADDR);
+		writew(0x4000, host->regs + NFC_V1_UNLOCKEND_BLKADDR);
+	} else
+		BUG();
+
+	/* Unlock Block Command for given address range */
+	writew(0x4, host->regs + NFC_WRPROT);
+}
+
 /* Used by the upper layer to write command to NAND Flash for
  * different operations to be carried out on NAND Flash */
 static void mxc_nand_command(struct mtd_info *mtd, unsigned command,
@@ -559,6 +594,10 @@

 	/* Command pre-processing step */
 	switch (command) {
+	case NAND_CMD_RESET:
+		send_cmd(host, command, false);
+		preset(mtd);
+		break;

 	case NAND_CMD_STATUS:
 		host->buf_start = 0;
@@ -679,7 +718,6 @@
 	struct mxc_nand_platform_data *pdata = pdev->dev.platform_data;
 	struct mxc_nand_host *host;
 	struct resource *res;
-	uint16_t tmp;
 	int err = 0, nr_parts = 0;
 	struct nand_ecclayout *oob_smallpage, *oob_largepage;

@@ -743,51 +781,17 @@
 		host->spare_len = 64;
 		oob_smallpage = &nandv2_hw_eccoob_smallpage;
 		oob_largepage = &nandv2_hw_eccoob_largepage;
+		this->ecc.bytes = 9;
 	} else if (nfc_is_v1()) {
 		host->regs = host->base;
 		host->spare0 = host->base + 0x800;
 		host->spare_len = 16;
 		oob_smallpage = &nandv1_hw_eccoob_smallpage;
 		oob_largepage = &nandv1_hw_eccoob_largepage;
-	} else
-		BUG();
-
-	/* disable interrupt and spare enable */
-	tmp = readw(host->regs + NFC_CONFIG1);
-	tmp |= NFC_INT_MSK;
-	tmp &= ~NFC_SP_EN;
-	writew(tmp, host->regs + NFC_CONFIG1);
-
-	init_waitqueue_head(&host->irq_waitq);
-
-	host->irq = platform_get_irq(pdev, 0);
-
-	err = request_irq(host->irq, mxc_nfc_irq, 0, DRIVER_NAME, host);
-	if (err)
-		goto eirq;
-
-	/* Reset NAND */
-	this->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
-
-	/* preset operation */
-	/* Unlock the internal RAM Buffer */
-	writew(0x2, host->regs + NFC_CONFIG);
-
-	/* Blocks to be unlocked */
-	if (nfc_is_v21()) {
-		writew(0x0, host->regs + NFC_V21_UNLOCKSTART_BLKADDR);
-	        writew(0xffff, host->regs + NFC_V21_UNLOCKEND_BLKADDR);
-		this->ecc.bytes = 9;
-	} else if (nfc_is_v1()) {
-		writew(0x0, host->regs + NFC_V1_UNLOCKSTART_BLKADDR);
-	        writew(0x4000, host->regs + NFC_V1_UNLOCKEND_BLKADDR);
 		this->ecc.bytes = 3;
 	} else
 		BUG();

-	/* Unlock Block Command for given address range */
-	writew(0x4, host->regs + NFC_WRPROT);
-
 	this->ecc.size = 512;
 	this->ecc.layout = oob_smallpage;

@@ -796,14 +800,8 @@
 		this->ecc.hwctl = mxc_nand_enable_hwecc;
 		this->ecc.correct = mxc_nand_correct_data;
 		this->ecc.mode = NAND_ECC_HW;
-		tmp = readw(host->regs + NFC_CONFIG1);
-		tmp |= NFC_ECC_EN;
-		writew(tmp, host->regs + NFC_CONFIG1);
 	} else {
 		this->ecc.mode = NAND_ECC_SOFT;
-		tmp = readw(host->regs + NFC_CONFIG1);
-		tmp &= ~NFC_ECC_EN;
-		writew(tmp, host->regs + NFC_CONFIG1);
 	}

 	/* NAND bus width determines access funtions used by upper layer */
@@ -817,6 +815,14 @@
 		this->options |= NAND_USE_FLASH_BBT;
 	}

+	init_waitqueue_head(&host->irq_waitq);
+
+	host->irq = platform_get_irq(pdev, 0);
+
+	err = request_irq(host->irq, mxc_nfc_irq, 0, DRIVER_NAME, host);
+	if (err)
+		goto eirq;
+
 	/* first scan to find the device and get the page size */
 	if (nand_scan_ident(mtd, 1)) {
 		err = -ENXIO;