mtd: nand: ndfc: add multiple chip select support

This patch extends NDFC driver to support all 4 chip selects
available in NDFC NAND controller. Tested on custom 460EX board
with 2 chip select NAND device.

Artem: white-space cleanups
Signed-off-by: NFelix Radensky <felix@embedded-sol.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/ndfc.c

@@ -33,6 +33,7 @@
 #include <linux/of_platform.h>
 #include <asm/io.h>
 
+#define NDFC_MAX_CS    4
 
 struct ndfc_controller {
 	struct platform_device *ofdev;
@@ -46,12 +47,13 @@ struct ndfc_controller {
 #endif
 };
 
-static struct ndfc_controller ndfc_ctrl;
+static struct ndfc_controller ndfc_ctrl[NDFC_MAX_CS];
 
 static void ndfc_select_chip(struct mtd_info *mtd, int chip)
 {
 	uint32_t ccr;
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *nchip = mtd->priv;
+	struct ndfc_controller *ndfc = nchip->priv;
 
 	ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
 	if (chip >= 0) {
@@ -64,7 +66,8 @@ static void ndfc_select_chip(struct mtd_info *mtd, int chip)
 
 static void ndfc_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 
 	if (cmd == NAND_CMD_NONE)
 		return;
@@ -77,7 +80,8 @@ static void ndfc_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
 
 static int ndfc_ready(struct mtd_info *mtd)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 
 	return in_be32(ndfc->ndfcbase + NDFC_STAT) & NDFC_STAT_IS_READY;
 }
@@ -85,7 +89,8 @@ static int ndfc_ready(struct mtd_info *mtd)
 static void ndfc_enable_hwecc(struct mtd_info *mtd, int mode)
 {
 	uint32_t ccr;
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 
 	ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
 	ccr |= NDFC_CCR_RESET_ECC;
@@ -96,7 +101,8 @@ static void ndfc_enable_hwecc(struct mtd_info *mtd, int mode)
 static int ndfc_calculate_ecc(struct mtd_info *mtd,
 			      const u_char *dat, u_char *ecc_code)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 	uint32_t ecc;
 	uint8_t *p = (uint8_t *)&ecc;
 
@@ -119,7 +125,8 @@ static int ndfc_calculate_ecc(struct mtd_info *mtd,
  */
 static void ndfc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 	uint32_t *p = (uint32_t *) buf;
 
 	for(;len > 0; len -= 4)
@@ -128,7 +135,8 @@ static void ndfc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 
 static void ndfc_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 	uint32_t *p = (uint32_t *) buf;
 
 	for(;len > 0; len -= 4)
@@ -137,7 +145,8 @@ static void ndfc_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 
 static int ndfc_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct nand_chip *chip = mtd->priv;
+	struct ndfc_controller *ndfc = chip->priv;
 	uint32_t *p = (uint32_t *) buf;
 
 	for(;len > 0; len -= 4)
@@ -179,6 +188,7 @@ static int ndfc_chip_init(struct ndfc_controller *ndfc,
 	chip->ecc.mode = NAND_ECC_HW;
 	chip->ecc.size = 256;
 	chip->ecc.bytes = 3;
+	chip->priv = ndfc;
 
 	ndfc->mtd.priv = chip;
 	ndfc->mtd.owner = THIS_MODULE;
@@ -227,15 +237,10 @@ static int ndfc_chip_init(struct ndfc_controller *ndfc,
 
 static int __devinit ndfc_probe(struct platform_device *ofdev)
 {
-	struct ndfc_controller *ndfc = &ndfc_ctrl;
+	struct ndfc_controller *ndfc;
 	const __be32 *reg;
 	u32 ccr;
-	int err, len;
-
-	spin_lock_init(&ndfc->ndfc_control.lock);
-	init_waitqueue_head(&ndfc->ndfc_control.wq);
-	ndfc->ofdev = ofdev;
-	dev_set_drvdata(&ofdev->dev, ndfc);
+	int err, len, cs;
 
 	/* Read the reg property to get the chip select */
 	reg = of_get_property(ofdev->dev.of_node, "reg", &len);
@@ -243,7 +248,20 @@ static int __devinit ndfc_probe(struct platform_device *ofdev)
 		dev_err(&ofdev->dev, "unable read reg property (%d)\n", len);
 		return -ENOENT;
 	}
-	ndfc->chip_select = be32_to_cpu(reg[0]);
+
+	cs = be32_to_cpu(reg[0]);
+	if (cs >= NDFC_MAX_CS) {
+		dev_err(&ofdev->dev, "invalid CS number (%d)\n", cs);
+		return -EINVAL;
+	}
+
+	ndfc = &ndfc_ctrl[cs];
+	ndfc->chip_select = cs;
+
+	spin_lock_init(&ndfc->ndfc_control.lock);
+	init_waitqueue_head(&ndfc->ndfc_control.wq);
+	ndfc->ofdev = ofdev;
+	dev_set_drvdata(&ofdev->dev, ndfc);
 
 	ndfc->ndfcbase = of_iomap(ofdev->dev.of_node, 0);
 	if (!ndfc->ndfcbase) {