From 11bff0b70cc003b995cf4c2acec4adab90957b02 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Thu, 3 Sep 2015 18:35:36 +0200 Subject: [PATCH] mtd: spi-nor: Decouple SPI NOR's device_node from controller device The problem this patch is trying to address is such, that SPI NOR flash devices attached to a dedicated SPI NOR controller cannot read their properties from the associated struct device_node. A couple of facts first: 1) Each SPI NOR flash has a struct spi_nor associated with it. 2) Each SPI NOR flash has certain device properties associated with it, for example the OF property 'm25p,fast-read' is a good pick. These properties are used by the SPI NOR core to select which opcodes are sent to such SPI NOR flash. These properties are coming from spi_nor .dev->of_node . The problem is, that for SPI NOR controllers, the struct spi_nor .dev element points to the struct device of the SPI NOR controller, not the SPI NOR flash. Therefore, the associated dev->of_node also is the one of the controller and therefore the SPI NOR core code is trying to parse the SPI NOR controller's properties, not the properties of the SPI NOR flash. Note: The m25p80 driver is not affected, because the controller and the flash are the same device, so the associated device_node of the controller and the flash are the same. This patch adjusts the SPI NOR core such that the device_node is not picked from spi_nor .dev directly, but from a new separate spi_nor .flash_node element. This let's the SPI NOR controller drivers set up a different spi_nor .flash_node element for each SPI NOR flash. This patch also fixes the controller drivers to be compatible with this modification and correctly set the spi_nor .flash_node element. This patch is inspired by 5844feeaa4154d1c46d3462c7a4653d22356d8b4 mtd: nand: add common DT init code Signed-off-by: Marek Vasut Signed-off-by: Brian Norris --- drivers/mtd/devices/m25p80.c | 1 + drivers/mtd/spi-nor/fsl-quadspi.c | 1 + drivers/mtd/spi-nor/nxp-spifi.c | 1 + drivers/mtd/spi-nor/spi-nor.c | 2 +- include/linux/mtd/spi-nor.h | 2 ++ 5 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index b6bc9a2a5f87..05bf0d71abea 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -200,6 +200,7 @@ static int m25p_probe(struct spi_device *spi) nor->read_reg = m25p80_read_reg; nor->dev = &spi->dev; + nor->flash_node = spi->dev.of_node; nor->priv = flash; spi_set_drvdata(spi, flash); diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c index f28dcc1cd63f..f72483247c75 100644 --- a/drivers/mtd/spi-nor/fsl-quadspi.c +++ b/drivers/mtd/spi-nor/fsl-quadspi.c @@ -1013,6 +1013,7 @@ static int fsl_qspi_probe(struct platform_device *pdev) mtd = &nor->mtd; nor->dev = dev; + nor->flash_node = np; nor->priv = q; /* fill the hooks */ diff --git a/drivers/mtd/spi-nor/nxp-spifi.c b/drivers/mtd/spi-nor/nxp-spifi.c index 0f6b452574bd..ce7bf6b2916b 100644 --- a/drivers/mtd/spi-nor/nxp-spifi.c +++ b/drivers/mtd/spi-nor/nxp-spifi.c @@ -331,6 +331,7 @@ static int nxp_spifi_setup_flash(struct nxp_spifi *spifi, writel(ctrl, spifi->io_base + SPIFI_CTRL); spifi->nor.dev = spifi->dev; + spifi->nor.flash_node = np; spifi->nor.priv = spifi; spifi->nor.read = nxp_spifi_read; spifi->nor.write = nxp_spifi_write; diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 55c67a4ea231..22cca87db9ca 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -1005,7 +1005,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) const struct flash_info *info = NULL; struct device *dev = nor->dev; struct mtd_info *mtd = &nor->mtd; - struct device_node *np = dev->of_node; + struct device_node *np = nor->flash_node; int ret; int i; diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 495433d3f56d..6379e107f2e5 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -134,6 +134,7 @@ struct mtd_info; * @mtd: point to a mtd_info structure * @lock: the lock for the read/write/erase/lock/unlock operations * @dev: point to a spi device, or a spi nor controller device. + * @flash_node: point to a device node describing this flash instance. * @page_size: the page size of the SPI NOR * @addr_width: number of address bytes * @erase_opcode: the opcode for erasing a sector @@ -165,6 +166,7 @@ struct spi_nor { struct mtd_info mtd; struct mutex lock; struct device *dev; + struct device_node *flash_node; u32 page_size; u8 addr_width; u8 erase_opcode; -- 2.20.1