| Message ID | 1544281933-21959-2-git-send-email-andrew@lunn.ch |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | platform data controls for mdio-gpio | expand |
Le 12/8/18 à 7:12 AM, Andrew Lunn a écrit : > 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 > -- > int -> u32 in platform data structure > > Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
diff --git a/MAINTAINERS b/MAINTAINERS index fb88b6863d10..9d3b899f9ba2 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -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, else 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 + */ + +#ifndef __LINUX_MDIO_GPIO_PDATA_H +#define __LINUX_MDIO_GPIO_PDATA_H + +struct mdio_gpio_platform_data { + u32 phy_mask; +}; + +#endif /* __LINUX_MDIO_GPIO_PDATA_H */
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 -- int -> u32 in platform data structure Signed-off-by: Andrew Lunn <andrew@lunn.ch> --- MAINTAINERS | 1 + drivers/net/phy/mdio-gpio.c | 5 +++++ include/linux/platform_data/mdio-gpio.h | 13 +++++++++++++ 3 files changed, 19 insertions(+) create mode 100644 include/linux/platform_data/mdio-gpio.h