Re: [PATCH v3.1 1/2] device property: Add device_get_bd_address() and fwnode_get_bd_address()
From: Sakari Ailus
Date: Tue Sep 25 2018 - 17:33:31 EST
Hi Matthias,
On Tue, Sep 25, 2018 at 12:10:13PM -0700, Matthias Kaehlcke wrote:
> Provide an API for Bluetooth drivers to retrieve the Bluetooth Device
> address (BD_ADDR) for a device. If the device node has a property
> 'local-bd-address' the BD address is read from this property.
>
> The definition of bdaddr_t is moved to types.h to make it visible in
> property.h without having to include (the mostly unrelated) bluetooth.h
>
> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> ---
> Changes in v3:
> - move definition of bdaddr_t to types.h to avoid include of
> bluetooth.h from property.h
> - add stubs for the new functions
>
> Changes in v2:
> - use bdaddr_t instead of byte pointer + len
> - use EXPORT_SYMBOL_GPL for the new functions instead of EXPORT_SYMBOL
> - put new functions inside #if IS_ENABLED(CONFIG_BT)
> - some new line juggling in property.h
> - added 'Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>' tag
> ---
> drivers/base/property.c | 46 +++++++++++++++++++++++++++++++
> include/linux/property.h | 18 ++++++++++++
> include/linux/types.h | 5 ++++
> include/net/bluetooth/bluetooth.h | 5 ----
> 4 files changed, 69 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index 240ab5230ff6..afe412133188 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c
> @@ -1315,6 +1315,52 @@ void *device_get_mac_address(struct device *dev, char *addr, int alen)
> }
> EXPORT_SYMBOL(device_get_mac_address);
>
> +#if IS_ENABLED(CONFIG_BT)
> +
> +/**
> + * fwnode_get_bd_address - Get the Bluetooth Device Address (BD_ADDR) from the
> + * firmware node
> + * @fwnode: Pointer to the firmware node
> + * @bd_addr: Pointer to struct to store the BD address in
> + *
> + * Search the firmware node for 'local-bd-address'.
> + *
> + * All-zero BD addresses are rejected, because those could be properties
> + * that exist in the firmware tables, but were not updated by the firmware. For
> + * example, the DTS could define 'local-bd-address', with zero BD addresses.
> + */
> +int fwnode_get_bd_address(struct fwnode_handle *fwnode, bdaddr_t *bd_addr)
> +{
> + bdaddr_t ba;
> + int ret;
> +
> + ret = fwnode_property_read_u8_array(fwnode, "local-bd-address",
> + (u8 *)&ba, sizeof(bdaddr_t));
sizeof(ba)
> + if (ret < 0)
> + return ret;
> + if (is_zero_ether_addr((u8 *)&ba))
> + return -ENODATA;
> +
> + memcpy(bd_addr, &ba, sizeof(bdaddr_t));
How about simply:
*bd_addr = ba;
Either way,
Reviewed-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(fwnode_get_bd_address);
> +
> +/**
> + * device_get_bd_address - Get the Bluetooth Device Address (BD_ADDR) for a
> + * given device
> + * @dev: Pointer to the device
> + * @bd_addr: Pointer to struct to store the BD address in
> + */
> +int device_get_bd_address(struct device *dev, bdaddr_t *bd_addr)
> +{
> + return fwnode_get_bd_address(dev_fwnode(dev), bd_addr);
> +}
> +EXPORT_SYMBOL_GPL(device_get_bd_address);
> +
> +#endif
> +
> /**
> * fwnode_irq_get - Get IRQ directly from a fwnode
> * @fwnode: Pointer to the firmware node
> diff --git a/include/linux/property.h b/include/linux/property.h
> index ac8a1ebc4c1b..5df4e0bd8c83 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h
> @@ -286,10 +286,28 @@ const void *device_get_match_data(struct device *dev);
> int device_get_phy_mode(struct device *dev);
>
> void *device_get_mac_address(struct device *dev, char *addr, int alen);
> +#if IS_ENABLED(CONFIG_BT)
> +int device_get_bd_address(struct device *dev, bdaddr_t *bd_addr);
> +#else
> +static inline int device_get_bd_address(struct device *dev,
> + bdaddr_t *bd_addr)
> +{
> + return -ENOTSUPP;
> +}
> +#endif
>
> int fwnode_get_phy_mode(struct fwnode_handle *fwnode);
> void *fwnode_get_mac_address(struct fwnode_handle *fwnode,
> char *addr, int alen);
> +#if IS_ENABLED(CONFIG_BT)
> +int fwnode_get_bd_address(struct fwnode_handle *fwnode, bdaddr_t *bd_addr);
> +#else
> +static inline int fwnode_get_bd_address(struct fwnode_handle *fwnode,
> + bdaddr_t *bd_addr)
> +{
> + return -ENOTSUPP;
> +}
> +#endif
> struct fwnode_handle *fwnode_graph_get_next_endpoint(
> const struct fwnode_handle *fwnode, struct fwnode_handle *prev);
> struct fwnode_handle *
> diff --git a/include/linux/types.h b/include/linux/types.h
> index 9834e90aa010..ff6984a00a3b 100644
> --- a/include/linux/types.h
> +++ b/include/linux/types.h
> @@ -230,5 +230,10 @@ struct callback_head {
> typedef void (*rcu_callback_t)(struct rcu_head *head);
> typedef void (*call_rcu_func_t)(struct rcu_head *head, rcu_callback_t func);
>
> +/* Bluetooth Device Address (BD_ADDR) */
> +typedef struct {
> + __u8 b[6];
> +} __packed bdaddr_t;
> +
> #endif /* __ASSEMBLY__ */
> #endif /* _LINUX_TYPES_H */
> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> index ec9d6bc65855..9401c7431a8f 100644
> --- a/include/net/bluetooth/bluetooth.h
> +++ b/include/net/bluetooth/bluetooth.h
> @@ -190,11 +190,6 @@ static inline const char *state_to_string(int state)
> return "invalid state";
> }
>
> -/* BD Address */
> -typedef struct {
> - __u8 b[6];
> -} __packed bdaddr_t;
> -
> /* BD Address type */
> #define BDADDR_BREDR 0x00
> #define BDADDR_LE_PUBLIC 0x01
--
Kind regards,
Sakari Ailus
sakari.ailus@xxxxxxxxxxxxxxx