| Message ID | 1398657227-20721-3-git-send-email-b32955@freescale.com |
|---|---|
| State | Deferred |
| Headers | show |
On Monday, April 28, 2014 at 05:53:39 AM, Huang Shijie wrote: > We need the SPI NOR child node to store some specific features, such as the > dummy cycles for the DDR Quad read. > > But now, we only have the @dev field in the spi_nor{}. The @dev may points > to a spi_device{} for m25p80, while it may points to a platform_deivice{} > for the SPI NOR controller, such as fsl_quadspi.c. > > It is not convenient for us to get come information from the SPI NOR flash. > > This patch adds a new field @np to spi_nor{}, it points to the child node > for the SPI NOR flash. > > Signed-off-by: Huang Shijie <b32955@freescale.com> Just handle the case where dev->of_node == NULL instead ? Best regards, Marek Vasut
On Mon, Apr 28, 2014 at 10:23:26PM +0200, Marek Vasut wrote: > On Monday, April 28, 2014 at 05:53:39 AM, Huang Shijie wrote: > > We need the SPI NOR child node to store some specific features, such as the > > dummy cycles for the DDR Quad read. > > > > But now, we only have the @dev field in the spi_nor{}. The @dev may points > > to a spi_device{} for m25p80, while it may points to a platform_deivice{} > > for the SPI NOR controller, such as fsl_quadspi.c. > > > > It is not convenient for us to get come information from the SPI NOR flash. > > > > This patch adds a new field @np to spi_nor{}, it points to the child node > > for the SPI NOR flash. > > > > Signed-off-by: Huang Shijie <b32955@freescale.com> > > Just handle the case where dev->of_node == NULL instead ? It is not enough. For the m25p80.c, @dev stands for a child node for the SPI master, and it points to a spi_device{}. Yes, in this case, the dev->of_node is NULL. But for the fsl_quadspi or other SPI NOR drivers, the @dev stands for the controller itself, the @dev->of_node is a list of the child nodes, so we can _NOT_ know which child node we are working at now. So it's better to add a new field @np for the spi-nor{} which points the child node we are working at. thanks Huang Shijie
On Tue, Apr 29, 2014 at 08:54:24AM +0200, Marek Vasut wrote: > On Tuesday, April 29, 2014 at 07:18:34 AM, Huang Shijie wrote: > > For the m25p80.c, @dev stands for a child node for the SPI master, > > and it points to a spi_device{}. Yes, in this case, the dev->of_node is > > NULL. > > > > But for the fsl_quadspi or other SPI NOR drivers, the @dev stands for the > > controller itself, the @dev->of_node is a list of the child nodes, so we > > can _NOT_ know which child node we are working at now. > > Huh ? The dev is being recycled for two different kind of things ? yes. for the SPI bus, the of_register_spi_devices() will allocate a spi_device{} for each child node for the SPI NOR flash. So in the m25p80.c, the @dev points to a spi_device{}. For the simplicity, we do not allocate any *_device{} for the child node in the SPI NOR flash driver, such as in the fsl-quadspi.c. thanks Huang Shijie
On Tuesday, April 29, 2014 at 07:18:34 AM, Huang Shijie wrote: > On Mon, Apr 28, 2014 at 10:23:26PM +0200, Marek Vasut wrote: > > On Monday, April 28, 2014 at 05:53:39 AM, Huang Shijie wrote: > > > We need the SPI NOR child node to store some specific features, such as > > > the dummy cycles for the DDR Quad read. > > > > > > But now, we only have the @dev field in the spi_nor{}. The @dev may > > > points to a spi_device{} for m25p80, while it may points to a > > > platform_deivice{} for the SPI NOR controller, such as fsl_quadspi.c. > > > > > > It is not convenient for us to get come information from the SPI NOR > > > flash. > > > > > > This patch adds a new field @np to spi_nor{}, it points to the child > > > node for the SPI NOR flash. > > > > > > Signed-off-by: Huang Shijie <b32955@freescale.com> > > > > Just handle the case where dev->of_node == NULL instead ? > > It is not enough. > > For the m25p80.c, @dev stands for a child node for the SPI master, > and it points to a spi_device{}. Yes, in this case, the dev->of_node is > NULL. > > But for the fsl_quadspi or other SPI NOR drivers, the @dev stands for the > controller itself, the @dev->of_node is a list of the child nodes, so we > can _NOT_ know which child node we are working at now. Huh ? The dev is being recycled for two different kind of things ? > So it's better to add a new field @np for the spi-nor{} which points the > child node we are working at. Best regards, Marek Vasut
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 3a1d9e0..f996c3a 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -215,6 +215,7 @@ static int m25p_probe(struct spi_device *spi) nor->read_reg = m25p80_read_reg; nor->dev = &spi->dev; + nor->np = spi->dev.of_node; nor->mtd = &flash->mtd; nor->priv = flash; diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 1a12f81..f374e44 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -891,7 +891,7 @@ int spi_nor_scan(struct spi_nor *nor, const struct spi_device_id *id, struct flash_platform_data *data; struct device *dev = nor->dev; struct mtd_info *mtd = nor->mtd; - struct device_node *np = dev->of_node; + struct device_node *np = nor->np; int ret; int i; diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 5324184..48fe9fc 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -117,6 +117,8 @@ enum spi_nor_ops { * @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. + * @np: If exit, it points to a device_node which stands for the + * SPI NOR flash child node. * @page_size: the page size of the SPI NOR * @addr_width: number of address bytes * @erase_opcode: the opcode for erasing a sector @@ -148,6 +150,7 @@ struct spi_nor { struct mtd_info *mtd; struct mutex lock; struct device *dev; + struct device_node *np; u32 page_size; u8 addr_width; u8 erase_opcode;
We need the SPI NOR child node to store some specific features, such as the dummy cycles for the DDR Quad read. But now, we only have the @dev field in the spi_nor{}. The @dev may points to a spi_device{} for m25p80, while it may points to a platform_deivice{} for the SPI NOR controller, such as fsl_quadspi.c. It is not convenient for us to get come information from the SPI NOR flash. This patch adds a new field @np to spi_nor{}, it points to the child node for the SPI NOR flash. Signed-off-by: Huang Shijie <b32955@freescale.com> --- drivers/mtd/devices/m25p80.c | 1 + drivers/mtd/spi-nor/spi-nor.c | 2 +- include/linux/mtd/spi-nor.h | 3 +++ 3 files changed, 5 insertions(+), 1 deletions(-)