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From:   Pratyush Yadav <p.yadav@ti.com>
To:     Tudor Ambarus <tudor.ambarus@microchip.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Mark Brown <broonie@kernel.org>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Ludovic Desroches <ludovic.desroches@microchip.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Michal Simek <michal.simek@xilinx.com>,
        <linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        <linux-spi@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-mediatek@lists.infradead.org>
CC:     Pratyush Yadav <p.yadav@ti.com>, Sekhar Nori <nsekhar@ti.com>,
        Boris Brezillon <boris.brezillon@collabora.com>,
        Mason Yang <masonccyang@mxic.com.tw>
Subject: [PATCH v8 14/19] mtd: spi-nor: sfdp: detect Soft Reset sequence support from BFPT
Date:   Sat, 23 May 2020 04:10:37 +0530
Message-ID: <20200522224042.29970-15-p.yadav@ti.com>
In-Reply-To: <20200522224042.29970-1-p.yadav@ti.com>
References: <20200522224042.29970-1-p.yadav@ti.com>
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A Soft Reset sequence will return the flash to Power-on-Reset (POR)
state. It consists of two commands: Soft Reset Enable and Soft Reset.
Find out if the sequence is supported from BFPT DWORD 16.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
---
 drivers/mtd/spi-nor/core.h | 1 +
 drivers/mtd/spi-nor/sfdp.c | 4 ++++
 drivers/mtd/spi-nor/sfdp.h | 2 ++
 3 files changed, 7 insertions(+)

diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 6338d32a0d77..79ce952c0539 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -26,6 +26,7 @@ enum spi_nor_option_flags {
 	SNOR_F_HAS_SR_TB_BIT6	= BIT(11),
 	SNOR_F_HAS_4BIT_BP      = BIT(12),
 	SNOR_F_HAS_SR_BP3_BIT6  = BIT(13),
+	SNOR_F_SOFT_RESET	= BIT(14),
 };
 
 struct spi_nor_read_command {
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index 9fd3d8d9a127..11109969dc3a 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -618,6 +618,10 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 		break;
 	}
 
+	/* Soft Reset support. */
+	if (bfpt.dwords[BFPT_DWORD(16)] & BFPT_DWORD16_SOFT_RST)
+		nor->flags |= SNOR_F_SOFT_RESET;
+
 	/* Stop here if JESD216 rev B. */
 	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216B)
 		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
diff --git a/drivers/mtd/spi-nor/sfdp.h b/drivers/mtd/spi-nor/sfdp.h
index e15e30796d62..d1d43ee09a0a 100644
--- a/drivers/mtd/spi-nor/sfdp.h
+++ b/drivers/mtd/spi-nor/sfdp.h
@@ -84,6 +84,8 @@ struct sfdp_bfpt {
 #define BFPT_DWORD15_QER_SR2_BIT1_NO_RD		(0x4UL << 20)
 #define BFPT_DWORD15_QER_SR2_BIT1		(0x5UL << 20) /* Spansion */
 
+#define BFPT_DWORD16_SOFT_RST			BIT(12)
+
 #define BFPT_DWORD18_CMD_EXT_MASK		GENMASK(30, 29)
 #define BFPT_DWORD18_CMD_EXT_REP		(0x0UL << 29) /* Repeat */
 #define BFPT_DWORD18_CMD_EXT_INV		(0x1UL << 29) /* Invert */
-- 
2.26.2