On 12/16/20 9:44 PM, Xu Yilun wrote:
> The match ops allows dfl drivers have their own matching algorithem
> instead of the standard id_table matching.
>
> This is to support the DFL UIO driver. It intends to match any DFL
> device which could not be handled by other DFL drivers.
>
> Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
This looks fine.
Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
> ---
> v3: this patch is splited out from DFL UIO patch.
> move the declarations of exported symbols from include/linux/dfl.h
> to driver/fpga/dfl.h
> fix some comments.
> ---
> drivers/fpga/dfl.c | 22 +++++++++++++++++-----
> drivers/fpga/dfl.h | 5 +++++
> include/linux/dfl.h | 3 +++
> 3 files changed, 25 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index 511b20f..dd90111 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -256,12 +256,13 @@ dfl_match_one_device(const struct dfl_device_id *id, struct dfl_device *ddev)
> return NULL;
> }
>
> -static int dfl_bus_match(struct device *dev, struct device_driver *drv)
> +int dfl_match_device(struct dfl_device *ddev, struct dfl_driver *ddrv)
> {
> - struct dfl_device *ddev = to_dfl_dev(dev);
> - struct dfl_driver *ddrv = to_dfl_drv(drv);
> const struct dfl_device_id *id_entry;
>
> + if (ddrv->match)
> + return ddrv->match(ddev);
> +
> id_entry = ddrv->id_table;
> if (id_entry) {
> while (id_entry->feature_id) {
> @@ -275,6 +276,15 @@ static int dfl_bus_match(struct device *dev, struct device_driver *drv)
>
> return 0;
> }
> +EXPORT_SYMBOL_GPL(dfl_match_device);
> +
> +static int dfl_bus_match(struct device *dev, struct device_driver *drv)
> +{
> + struct dfl_device *ddev = to_dfl_dev(dev);
> + struct dfl_driver *ddrv = to_dfl_drv(drv);
> +
> + return dfl_match_device(ddev, ddrv);
> +}
>
> static int dfl_bus_probe(struct device *dev)
> {
> @@ -328,7 +338,7 @@ static struct attribute *dfl_dev_attrs[] = {
> };
> ATTRIBUTE_GROUPS(dfl_dev);
>
> -static struct bus_type dfl_bus_type = {
> +struct bus_type dfl_bus_type = {
> .name = "dfl",
> .match = dfl_bus_match,
> .probe = dfl_bus_probe,
> @@ -336,6 +346,7 @@ static struct bus_type dfl_bus_type = {
> .uevent = dfl_bus_uevent,
> .dev_groups = dfl_dev_groups,
> };
> +EXPORT_SYMBOL_GPL(dfl_bus_type);
>
> static void release_dfl_dev(struct device *dev)
> {
> @@ -469,7 +480,8 @@ static int dfl_devs_add(struct dfl_feature_platform_data *pdata)
>
> int __dfl_driver_register(struct dfl_driver *dfl_drv, struct module *owner)
> {
> - if (!dfl_drv || !dfl_drv->probe || !dfl_drv->id_table)
> + if (!dfl_drv || !dfl_drv->probe ||
> + (!dfl_drv->id_table && !dfl_drv->match))
> return -EINVAL;
>
> dfl_drv->drv.owner = owner;
> diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
> index 2b82c96..01c43d8 100644
> --- a/drivers/fpga/dfl.h
> +++ b/drivers/fpga/dfl.h
> @@ -17,6 +17,7 @@
> #include <linux/bitfield.h>
> #include <linux/cdev.h>
> #include <linux/delay.h>
> +#include <linux/dfl.h>
> #include <linux/eventfd.h>
> #include <linux/fs.h>
> #include <linux/interrupt.h>
> @@ -517,4 +518,8 @@ long dfl_feature_ioctl_set_irq(struct platform_device *pdev,
> struct dfl_feature *feature,
> unsigned long arg);
>
> +extern struct bus_type dfl_bus_type;
> +
> +int dfl_match_device(struct dfl_device *ddev, struct dfl_driver *ddrv);
> +
> #endif /* __FPGA_DFL_H */
> diff --git a/include/linux/dfl.h b/include/linux/dfl.h
> index 6cc1098..cfd98a4 100644
> --- a/include/linux/dfl.h
> +++ b/include/linux/dfl.h
> @@ -51,6 +51,8 @@ struct dfl_device {
> * @drv: driver model structure.
> * @id_table: pointer to table of device IDs the driver is interested in.
> * { } member terminated.
> + * @match: returns one if given device can be handled by the driver and zero
> + * otherwise. If NULL, matching is based on id_table.
> * @probe: mandatory callback for device binding.
> * @remove: callback for device unbinding.
> */
> @@ -58,6 +60,7 @@ struct dfl_driver {
> struct device_driver drv;
> const struct dfl_device_id *id_table;
>
> + int (*match)(struct dfl_device *dfl_dev);
> int (*probe)(struct dfl_device *dfl_dev);
> void (*remove)(struct dfl_device *dfl_dev);
> };
