[PATCH v2 1/6] mtd: spi-nor: Add post_sfdp() hook to tweak flash config

From: <Tudor.Ambarus@microchip.com>
To: <boris.brezillon@collabora.com>, <marek.vasut@gmail.com>,
	<vigneshr@ti.com>, <miquel.raynal@bootlin.com>, <richard@nod.at>,
	<linux-mtd@lists.infradead.org>, <linux-kernel@vger.kernel.org>
Cc: <boris.brezillon@bootlin.com>, <Tudor.Ambarus@microchip.com>
Subject: [PATCH v2 1/6] mtd: spi-nor: Add post_sfdp() hook to tweak flash config
Date: Sat, 24 Aug 2019 12:07:09 +0000	[thread overview]
Message-ID: <20190824120650.14752-2-tudor.ambarus@microchip.com> (raw)
In-Reply-To: <20190824120650.14752-1-tudor.ambarus@microchip.com>

From: Boris Brezillon <boris.brezillon@bootlin.com>

SFDP tables are sometimes wrong and we need a way to override the
config chosen by the SFDP parsing logic without discarding all of it.

Add a new hook called after the SFDP parsing has taken place to deal
with such problems.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 drivers/mtd/spi-nor/spi-nor.c | 33 ++++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index f4e9fcca619f..41dc95415260 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -158,6 +158,11 @@ struct sfdp_bfpt {
  *                flash parameters when information provided by the flash_info
  *                table is incomplete or wrong.
  * @post_bfpt: called after the BFPT table has been parsed
+ * @post_sfdp: called after SFDP has been parsed (is also called for SPI NORs
+ *             that do not support RDSFDP). Typically used to tweak various
+ *             parameters that could not be extracted by other means (i.e.
+ *             when information provided by the SFDP/flash_info tables are
+ *             incomplete or wrong).
  *
  * Those hooks can be used to tweak the SPI NOR configuration when the SFDP
  * table is broken or not available.
@@ -168,6 +173,7 @@ struct spi_nor_fixups {
 			 const struct sfdp_parameter_header *bfpt_header,
 			 const struct sfdp_bfpt *bfpt,
 			 struct spi_nor_flash_parameter *params);
+	void (*post_sfdp)(struct spi_nor *nor);
 };
 
 struct flash_info {
@@ -4317,6 +4323,22 @@ static void spi_nor_legacy_init_params(struct spi_nor *nor)
 }
 
 /**
+ * spi_nor_post_sfdp_fixups() - Updates the flash's parameters and settings
+ * after SFDP has been parsed (is also called for SPI NORs that do not
+ * support RDSFDP).
+ * @nor:	pointer to a 'struct spi_nor'
+ *
+ * Typically used to tweak various parameters that could not be extracted by
+ * other means (i.e. when information provided by the SFDP/flash_info tables
+ * are incomplete or wrong).
+ */
+static void spi_nor_post_sfdp_fixups(struct spi_nor *nor)
+{
+	if (nor->info->fixups && nor->info->fixups->post_sfdp)
+		nor->info->fixups->post_sfdp(nor);
+}
+
+/**
  * spi_nor_late_init_params() - Late initialization of legacy flash parameters.
  * @nor:	pointer to a 'struct spi_nor'
  *
@@ -4359,7 +4381,14 @@ static void spi_nor_late_init_params(struct spi_nor *nor)
  *    flash parameters and settings imediately after parsing the Basic Flash
  *    Parameter Table.
  *
- * 4/ Late legacy flash parameters initialization, used when the
+ * which can be overwritten by:
+ * 4/ Post SFDP flash parameters initialization. Used to tweak various
+ *    parameters that could not be extracted by other means (i.e. when
+ *    information provided by the SFDP/flash_info tables are incomplete or
+ *    wrong).
+ *		spi_nor_post_sfdp_fixups()
+ *
+ * 5/ Late legacy flash parameters initialization, used when the
  * ->default_init() hook or the SFDP parser do not set specific params.
  *		spi_nor_late_init_params()
  */
@@ -4373,6 +4402,8 @@ static void spi_nor_init_params(struct spi_nor *nor)
 	    !(nor->info->flags & SPI_NOR_SKIP_SFDP))
 		spi_nor_sfdp_init_params(nor);
 
+	spi_nor_post_sfdp_fixups(nor);
+
 	spi_nor_late_init_params(nor);
 }
 
-- 
2.9.5

