Revert "mtd: atmel_nand: Support variable RB_EDGE interrupts"

This reverts commit 5ddc7bd4 ("mtd: atmel_nand: Support variable
RB_EDGE interrupts")

Because for current SoCs, the RB_EDGE3(i.e. bit 27) of HSMC_SR
register does not exist, the RB_EDGE0 (i.e. bit 24) is the ready/busy
line edge status bit. It is a datasheet bug.

Cc: <stable@vger.kernel.org>
Fixes: commit 5ddc7bd4 ("mtd: atmel_nand: Support variable RB_EDGE interrupts")
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

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.

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