An integrated multiplexer uses same address space for "muxed bus selection" and "generation of mdio transaction" hence its good to register parent bus from mux driver.
Hence added a mechanism where mux driver could register a parent bus and pass it down to framework via mdio_mux_init api. Below changes are required to make this happen- 1. When mdio-mux parent bus is registered, mdio framework should not parse for child as it will be muxed bus node not PHYs. -created a new property "mdio-mux-bus-parent". if this property is present, of_mdiobus_register will not scan for phys. 2. Passed down parent bus to mdio mux framework via mdio-mux-init api. Signed-off-by: Pramod Kumar <pramod.ku...@broadcom.com> --- drivers/net/phy/mdio-mux-gpio.c | 2 +- drivers/net/phy/mdio-mux-mmioreg.c | 2 +- drivers/net/phy/mdio-mux.c | 28 ++++++++++++++++++---------- drivers/of/of_mdio.c | 3 +++ include/linux/mdio-mux.h | 4 +++- 5 files changed, 26 insertions(+), 13 deletions(-) diff --git a/drivers/net/phy/mdio-mux-gpio.c b/drivers/net/phy/mdio-mux-gpio.c index 7ddb1ab..9199499 100644 --- a/drivers/net/phy/mdio-mux-gpio.c +++ b/drivers/net/phy/mdio-mux-gpio.c @@ -55,7 +55,7 @@ static int mdio_mux_gpio_probe(struct platform_device *pdev) return PTR_ERR(s->gpios); r = mdio_mux_init(&pdev->dev, - mdio_mux_gpio_switch_fn, &s->mux_handle, s); + mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL); if (r != 0) { gpiod_put_array(s->gpios); diff --git a/drivers/net/phy/mdio-mux-mmioreg.c b/drivers/net/phy/mdio-mux-mmioreg.c index 7fde454..d0bed52 100644 --- a/drivers/net/phy/mdio-mux-mmioreg.c +++ b/drivers/net/phy/mdio-mux-mmioreg.c @@ -126,7 +126,7 @@ static int mdio_mux_mmioreg_probe(struct platform_device *pdev) } ret = mdio_mux_init(&pdev->dev, mdio_mux_mmioreg_switch_fn, - &s->mux_handle, s); + &s->mux_handle, s, NULL); if (ret) { dev_err(&pdev->dev, "failed to register mdio-mux bus %s\n", np->full_name); diff --git a/drivers/net/phy/mdio-mux.c b/drivers/net/phy/mdio-mux.c index 308ade0..521ab90 100644 --- a/drivers/net/phy/mdio-mux.c +++ b/drivers/net/phy/mdio-mux.c @@ -95,7 +95,8 @@ static int parent_count; int mdio_mux_init(struct device *dev, int (*switch_fn)(int cur, int desired, void *data), void **mux_handle, - void *data) + void *data, + struct mii_bus *mux_bus) { struct device_node *parent_bus_node; struct device_node *child_bus_node; @@ -107,10 +108,21 @@ int mdio_mux_init(struct device *dev, if (!dev->of_node) return -ENODEV; - parent_bus_node = of_parse_phandle(dev->of_node, "mdio-parent-bus", 0); + if (!mux_bus) { + parent_bus_node = of_parse_phandle(dev->of_node, + "mdio-parent-bus", 0); - if (!parent_bus_node) - return -ENODEV; + if (!parent_bus_node) + return -ENODEV; + + parent_bus = of_mdio_find_bus(parent_bus_node); + if (!parent_bus) { + ret_val = -EPROBE_DEFER; + goto err_parent_bus; + } + } else { + parent_bus = mux_bus; + } pb = devm_kzalloc(dev, sizeof(*pb), GFP_KERNEL); if (pb == NULL) { @@ -118,11 +130,6 @@ int mdio_mux_init(struct device *dev, goto err_parent_bus; } - parent_bus = of_mdio_find_bus(parent_bus_node); - if (parent_bus == NULL) { - ret_val = -EPROBE_DEFER; - goto err_parent_bus; - } pb->switch_data = data; pb->switch_fn = switch_fn; @@ -183,7 +190,8 @@ int mdio_mux_init(struct device *dev, put_device(&pb->mii_bus->dev); err_parent_bus: - of_node_put(parent_bus_node); + if (!mux_bus) + of_node_put(parent_bus_node); return ret_val; } EXPORT_SYMBOL_GPL(mdio_mux_init); diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c index 8453f08..cf40e7a 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -225,6 +225,9 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np) if (rc) return rc; + if (of_property_read_bool(np, "mdio-integrated-mux")) + return 0; + /* Loop over the child nodes and register a phy_device for each phy */ for_each_available_child_of_node(np, child) { addr = of_mdio_parse_addr(&mdio->dev, child); diff --git a/include/linux/mdio-mux.h b/include/linux/mdio-mux.h index a243dbb..61f5b21 100644 --- a/include/linux/mdio-mux.h +++ b/include/linux/mdio-mux.h @@ -10,11 +10,13 @@ #ifndef __LINUX_MDIO_MUX_H #define __LINUX_MDIO_MUX_H #include <linux/device.h> +#include <linux/phy.h> int mdio_mux_init(struct device *dev, int (*switch_fn) (int cur, int desired, void *data), void **mux_handle, - void *data); + void *data, + struct mii_bus *mux_bus); void mdio_mux_uninit(void *mux_handle); -- 1.9.1