MTD fixes for v4.7-rc1

We've already noticed a few flaws in the MTD work for v4.7-rc1:
 
  * The Atmel folks got ahead of themselves on trying to support their latest
    hardware and were working off incorrect documentation. Fix up the NAND
    driver to get this correct.
 
  * Fix up device tree example documentation to use the latest recommendations
    for describing NAND ECC algorithms.
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Merge tag 'for-linus-20160527' of git://git.infradead.org/linux-mtd

Pull MTD fixes from Brian Norris:
 "We've already noticed a few flaws in the MTD work for v4.7-rc1:

   - The Atmel folks got ahead of themselves on trying to support their
     latest hardware and were working off incorrect documentation.  Fix
     up the NAND driver to get this correct.

   - Fix up device tree example documentation to use the latest
     recommendations for describing NAND ECC algorithms"

* tag 'for-linus-20160527' of git://git.infradead.org/linux-mtd:
  Documentation: dt: mtd: drop "soft_bch" from example
  Revert "mtd: atmel_nand: Support variable RB_EDGE interrupts"

Documentation/devicetree/bindings/mtd/atmel-nand.txt

@@ -39,7 +39,7 @@ Optional properties:
 
 Nand Flash Controller(NFC) is an optional sub-node
 Required properties:
-- compatible : "atmel,sama5d3-nfc" or "atmel,sama5d4-nfc".
+- compatible : "atmel,sama5d3-nfc".
 - reg : should specify the address and size used for NFC command registers,
         NFC registers and NFC SRAM. NFC SRAM address and size can be absent
         if don't want to use it.

Documentation/devicetree/bindings/mtd/nand.txt

@@ -53,7 +53,8 @@ Example:
 
 		nand@0 {
 			reg = <0>;
-			nand-ecc-mode = "soft_bch";
+			nand-ecc-mode = "soft";
+			nand-ecc-algo = "bch";
 
 			/* controller specific properties */
 		};

drivers/mtd/nand/atmel_nand.c

@@ -67,10 +67,6 @@ struct atmel_nand_caps {
 	uint8_t pmecc_max_correction;
 };
 
-struct atmel_nand_nfc_caps {
-	uint32_t rb_mask;
-};
-
 /*
  * oob layout for large page size
  * bad block info is on bytes 0 and 1
@@ -129,7 +125,6 @@ struct atmel_nfc {
 	/* Point to the sram bank which include readed data via NFC */
 	void			*data_in_sram;
 	bool			will_write_sram;
-	const struct atmel_nand_nfc_caps *caps;
 };
 static struct atmel_nfc	nand_nfc;
 
@@ -1715,9 +1710,9 @@ static irqreturn_t hsmc_interrupt(int irq, void *dev_id)
 		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_XFR_DONE);
 		ret = IRQ_HANDLED;
 	}
-	if (pending & host->nfc->caps->rb_mask) {
+	if (pending & NFC_SR_RB_EDGE) {
 		complete(&host->nfc->comp_ready);
-		nfc_writel(host->nfc->hsmc_regs, IDR, host->nfc->caps->rb_mask);
+		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_RB_EDGE);
 		ret = IRQ_HANDLED;
 	}
 	if (pending & NFC_SR_CMD_DONE) {
@@ -1735,7 +1730,7 @@ static void nfc_prepare_interrupt(struct atmel_nand_host *host, u32 flag)
 	if (flag & NFC_SR_XFR_DONE)
 		init_completion(&host->nfc->comp_xfer_done);
 
-	if (flag & host->nfc->caps->rb_mask)
+	if (flag & NFC_SR_RB_EDGE)
 		init_completion(&host->nfc->comp_ready);
 
 	if (flag & NFC_SR_CMD_DONE)
@@ -1753,7 +1748,7 @@ static int nfc_wait_interrupt(struct atmel_nand_host *host, u32 flag)
 	if (flag & NFC_SR_XFR_DONE)
 		comp[index++] = &host->nfc->comp_xfer_done;
 
-	if (flag & host->nfc->caps->rb_mask)
+	if (flag & NFC_SR_RB_EDGE)
 		comp[index++] = &host->nfc->comp_ready;
 
 	if (flag & NFC_SR_CMD_DONE)
@@ -1821,7 +1816,7 @@ static int nfc_device_ready(struct mtd_info *mtd)
 		dev_err(host->dev, "Lost the interrupt flags: 0x%08x\n",
 				mask & status);
 
-	return status & host->nfc->caps->rb_mask;
+	return status & NFC_SR_RB_EDGE;
 }
 
 static void nfc_select_chip(struct mtd_info *mtd, int chip)
@@ -1994,8 +1989,8 @@ static void nfc_nand_command(struct mtd_info *mtd, unsigned int command,
 		}
 		/* fall through */
 	default:
-		nfc_prepare_interrupt(host, host->nfc->caps->rb_mask);
-		nfc_wait_interrupt(host, host->nfc->caps->rb_mask);
+		nfc_prepare_interrupt(host, NFC_SR_RB_EDGE);
+		nfc_wait_interrupt(host, NFC_SR_RB_EDGE);
 	}
 }
 
@@ -2426,11 +2421,6 @@ static int atmel_nand_nfc_probe(struct platform_device *pdev)
 		}
 	}
 
-	nfc->caps = (const struct atmel_nand_nfc_caps *)
-		of_device_get_match_data(&pdev->dev);
-	if (!nfc->caps)
-		return -ENODEV;
-
 	nfc_writel(nfc->hsmc_regs, IDR, 0xffffffff);
 	nfc_readl(nfc->hsmc_regs, SR);	/* clear the NFC_SR */
 
@@ -2459,17 +2449,8 @@ static int atmel_nand_nfc_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct atmel_nand_nfc_caps sama5d3_nfc_caps = {
-	.rb_mask = NFC_SR_RB_EDGE0,
-};
-
-static const struct atmel_nand_nfc_caps sama5d4_nfc_caps = {
-	.rb_mask = NFC_SR_RB_EDGE3,
-};
-
 static const struct of_device_id atmel_nand_nfc_match[] = {
-	{ .compatible = "atmel,sama5d3-nfc", .data = &sama5d3_nfc_caps },
-	{ .compatible = "atmel,sama5d4-nfc", .data = &sama5d4_nfc_caps },
+	{ .compatible = "atmel,sama5d3-nfc" },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, atmel_nand_nfc_match);

drivers/mtd/nand/atmel_nand_nfc.h

@@ -42,8 +42,7 @@
 #define		NFC_SR_UNDEF		(1 << 21)
 #define		NFC_SR_AWB		(1 << 22)
 #define		NFC_SR_ASE		(1 << 23)
-#define		NFC_SR_RB_EDGE0		(1 << 24)
-#define		NFC_SR_RB_EDGE3		(1 << 27)
+#define		NFC_SR_RB_EDGE		(1 << 24)
 
 #define ATMEL_HSMC_NFC_IER	0x0c
 #define ATMEL_HSMC_NFC_IDR	0x10