On Thu, 2 Aug 2018 14:53:53 +0200
Frieder Schrempf <frieder.schre...@exceet.de> wrote:
> When porting (Q)SPI controller drivers from the MTD layer to the SPI
> layer, the naming scheme for the memory devices changes. To be able
> to keep compatibility with the old drivers naming scheme, a name
> field is added to struct spi_mem and a hook is added to let controller
> drivers set a custom name for the memory device.
>
> Example for the FSL QSPI driver:
>
> Name with the old driver: 21e0000.qspi,
> or with multiple devices: 21e0000.qspi-0, 21e0000.qspi-1, ...
>
> Name with the new driver without spi_mem_get_name: spi4.0
>
> Suggested-by: Boris Brezillon <boris.brezil...@bootlin.com>
> Signed-off-by: Frieder Schrempf <frieder.schre...@exceet.de>
Reviewed-by: Boris Brezillon <boris.brezil...@bootlin.com>
> ---
> drivers/spi/spi-mem.c | 28 ++++++++++++++++++++++++++++
> include/linux/spi/spi-mem.h | 12 ++++++++++++
> 2 files changed, 40 insertions(+)
>
> diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
> index 990770d..e43842c 100644
> --- a/drivers/spi/spi-mem.c
> +++ b/drivers/spi/spi-mem.c
> @@ -311,6 +311,24 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct
> spi_mem_op *op)
> EXPORT_SYMBOL_GPL(spi_mem_exec_op);
>
> /**
> + * spi_mem_get_name() - Return the SPI mem device name to be used by the
> + * upper layer if necessary
> + * @mem: the SPI memory
> + *
> + * This function allows SPI mem users to retrieve the SPI mem device name.
> + * It is useful if the upper layer needs to expose a custom name for
> + * compatibility reasons.
> + *
> + * Return: a string containing the name of the memory device to be used
> + * by the SPI mem user
> + */
> +const char *spi_mem_get_name(struct spi_mem *mem)
> +{
> + return mem->name;
> +}
> +EXPORT_SYMBOL_GPL(spi_mem_get_name);
> +
> +/**
> * spi_mem_adjust_op_size() - Adjust the data size of a SPI mem operation to
> * match controller limitations
> * @mem: the SPI memory
> @@ -344,6 +362,7 @@ static inline struct spi_mem_driver
> *to_spi_mem_drv(struct device_driver *drv)
> static int spi_mem_probe(struct spi_device *spi)
> {
> struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver);
> + struct spi_controller *ctlr = spi->controller;
> struct spi_mem *mem;
>
> mem = devm_kzalloc(&spi->dev, sizeof(*mem), GFP_KERNEL);
> @@ -351,6 +370,15 @@ static int spi_mem_probe(struct spi_device *spi)
> return -ENOMEM;
>
> mem->spi = spi;
> +
> + if (ctlr->mem_ops && ctlr->mem_ops->get_name)
> + mem->name = ctlr->mem_ops->get_name(mem);
> + else
> + mem->name = dev_name(&spi->dev);
> +
> + if (IS_ERR_OR_NULL(mem->name))
> + return PTR_ERR(mem->name);
> +
> spi_set_drvdata(spi, mem);
>
> return memdrv->probe(mem);
> diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h
> index 72cc9bc..0d41826 100644
> --- a/include/linux/spi/spi-mem.h
> +++ b/include/linux/spi/spi-mem.h
> @@ -125,6 +125,7 @@ struct spi_mem_op {
> * struct spi_mem - describes a SPI memory device
> * @spi: the underlying SPI device
> * @drvpriv: spi_mem_driver private data
> + * @name: name of the SPI memory device
> *
> * Extra information that describe the SPI memory device and may be needed by
> * the controller to properly handle this device should be placed here.
> @@ -135,6 +136,7 @@ struct spi_mem_op {
> struct spi_mem {
> struct spi_device *spi;
> void *drvpriv;
> + char *name;
> };
>
> /**
> @@ -167,6 +169,13 @@ static inline void *spi_mem_get_drvdata(struct spi_mem
> *mem)
> * limitations)
> * @supports_op: check if an operation is supported by the controller
> * @exec_op: execute a SPI memory operation
> + * @get_name: get a custom name for the SPI mem device from the controller.
> + * This might be needed if the controller driver has been ported
> + * to use the SPI mem layer and a custom name is used to keep
> + * mtdparts compatible.
> + * Note that if the implementation of this function allocates memory
> + * dynamically, then it should do so with devm_xxx(), as we don't
> + * have a ->free_name() function.
> *
> * This interface should be implemented by SPI controllers providing an
> * high-level interface to execute SPI memory operation, which is usually the
> @@ -178,6 +187,7 @@ struct spi_controller_mem_ops {
> const struct spi_mem_op *op);
> int (*exec_op)(struct spi_mem *mem,
> const struct spi_mem_op *op);
> + const char *(*get_name)(struct spi_mem *mem);
> };
>
> /**
> @@ -236,6 +246,8 @@ bool spi_mem_supports_op(struct spi_mem *mem,
> int spi_mem_exec_op(struct spi_mem *mem,
> const struct spi_mem_op *op);
>
> +const char *spi_mem_get_name(struct spi_mem *mem);
> +
> int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv,
> struct module *owner);
>
