diff options
authorAndrew Lunn <andrew@lunn.ch>2018-12-08 16:12:12 +0100
committerDavid S. Miller <davem@davemloft.net>2018-12-08 21:33:30 -0800
commit04fa26bab06d9335f15a5d529c4bba25cd507a34 (patch)
parentip: silence udp zerocopy smatch false positive (diff)
net: phy: mdio-gpio: Add platform_data support for phy_mask
It is sometimes necessary to instantiate a bit-banging MDIO bus as a platform device, without the aid of device tree. When device tree is being used, the bus is not scanned for devices, only those devices which are in device tree are probed. Without device tree, by default, all addresses on the bus are scanned. This may then find a device which is not a PHY, e.g. a switch. And the switch may have registers containing values which look like a PHY. So during the scan, a PHY device is wrongly created. After the bus has been registered, a search is made for mdio_board_info structures which indicates devices on the bus, and the driver which should be used for them. This is typically used to instantiate Ethernet switches from platform drivers. However, if the scanning of the bus has created a PHY device at the same location as indicated into the board info for a switch, the switch device is not created, since the address is already busy. This can be avoided by setting the phy_mask of the mdio bus. This mask prevents addresses on the bus being scanned. v2 Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
3 files changed, 19 insertions, 0 deletions
index 6db870b9d681..59bf56fa2a86 100644
@@ -5610,6 +5610,7 @@ F: include/linux/of_net.h
F: include/linux/phy.h
F: include/linux/phy_fixed.h
F: include/linux/platform_data/mdio-bcm-unimac.h
+F: include/linux/platform_data/mdio-gpio.h
F: include/trace/events/mdio.h
F: include/uapi/linux/mdio.h
F: include/uapi/linux/mii.h
diff --git a/drivers/net/phy/mdio-gpio.c b/drivers/net/phy/mdio-gpio.c
index 0fbcedcdf6e2..1e296dd4067a 100644
--- a/drivers/net/phy/mdio-gpio.c
+++ b/drivers/net/phy/mdio-gpio.c
@@ -24,6 +24,7 @@
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
+#include <linux/platform_data/mdio-gpio.h>
#include <linux/mdio-bitbang.h>
#include <linux/mdio-gpio.h>
#include <linux/gpio/consumer.h>
@@ -112,6 +113,7 @@ static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
struct mdio_gpio_info *bitbang,
int bus_id)
+ struct mdio_gpio_platform_data *pdata = dev_get_platdata(dev);
struct mii_bus *new_bus;
bitbang->ctrl.ops = &mdio_gpio_ops;
@@ -128,6 +130,9 @@ static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
strncpy(new_bus->id, "gpio", MII_BUS_ID_SIZE);
+ if (pdata)
+ new_bus->phy_mask = pdata->phy_mask;
dev_set_drvdata(dev, new_bus);
return new_bus;
diff --git a/include/linux/platform_data/mdio-gpio.h b/include/linux/platform_data/mdio-gpio.h
new file mode 100644
index 000000000000..a5d5ff5e174c
--- /dev/null
+++ b/include/linux/platform_data/mdio-gpio.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+ * MDIO-GPIO bus platform data structure
+ */
+struct mdio_gpio_platform_data {
+ u32 phy_mask;
+#endif /* __LINUX_MDIO_GPIO_PDATA_H */