[PATCH 5/5] mtd OMAP NAND: implement buswidth autodetection support

[Sascha Hauer]

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 drivers/mtd/nand/nand_omap_gpmc.c |   44 ++++++++++++++++++++++++++-----------
 1 file changed, 31 insertions(+), 13 deletions(-)

diff --git a/drivers/mtd/nand/nand_omap_gpmc.c b/drivers/mtd/nand/nand_omap_gpmc.c
index 39b4dd9..fa6074f 100644
--- a/drivers/mtd/nand/nand_omap_gpmc.c
+++ b/drivers/mtd/nand/nand_omap_gpmc.c
@@ -879,6 +879,20 @@ static int omap_gpmc_eccmode_set(struct device_d *dev, struct param_d *param, co
 	return omap_gpmc_eccmode(oinfo, i);
 }
 
+static int gpmc_set_buswidth(struct mtd_info *mtd, struct nand_chip *chip, int buswidth)
+{
+	struct gpmc_nand_info *oinfo = chip->priv;
+
+	if (buswidth == NAND_BUSWIDTH_16)
+		oinfo->pdata->nand_cfg->cfg[0] |= 0x00001000;
+	else
+		oinfo->pdata->nand_cfg->cfg[0] &= ~0x00001000;
+
+	gpmc_cs_config(oinfo->pdata->cs, oinfo->pdata->nand_cfg);
+
+	return 0;
+}
+
 /**
  * @brief nand device probe.
  *
@@ -934,10 +948,18 @@ static int gpmc_nand_probe(struct device_d *pdev)
 		oinfo->gpmc_base, oinfo->gpmc_command, oinfo->gpmc_address,
 		oinfo->gpmc_data, cs_base);
 
-	/* If we are 16 bit dev, our gpmc config tells us that */
-	if ((readl(cs_base) & 0x3000) == 0x1000) {
-		dev_dbg(pdev, "16 bit dev\n");
+	switch (pdata->device_width) {
+	case 0:
+		printk("probe buswidth\n");
+		nand->options |= NAND_BUSWIDTH_AUTO;
+		break;
+	case 8:
+		break;
+	case 16:
 		nand->options |= NAND_BUSWIDTH_16;
+		break;
+	default:
+		return -EINVAL;
 	}
 
 	/* Same data register for in and out */
@@ -977,6 +999,8 @@ static int gpmc_nand_probe(struct device_d *pdev)
 	nand->options |= NAND_OWN_BUFFERS;
 	nand->buffers = xzalloc(sizeof(*nand->buffers));
 
+	nand->set_buswidth = gpmc_set_buswidth;
+
 	/* State my controller */
 	nand->controller = &oinfo->controller;
 
@@ -1004,18 +1028,12 @@ static int gpmc_nand_probe(struct device_d *pdev)
 		goto out_release_mem;
 	}
 
-	switch (pdata->device_width) {
-	case 8:
-		lsp = &ecc_sp_x8;
-		llp = &ecc_lp_x8;
-		break;
-	case 16:
+	if (nand->options & NAND_BUSWIDTH_16) {
 		lsp = &ecc_sp_x16;
 		llp = &ecc_lp_x16;
-		break;
-	default:
-		err = -EINVAL;
-		goto out_release_mem;
+	} else {
+		lsp = &ecc_sp_x8;
+		llp = &ecc_lp_x8;
 	}
 
 	switch (minfo->writesize) {
-- 
1.7.10.4