[PATCH v4 01/11] net: phy: Add support for microchip SMI0 MDIO bus
From: Michael Grzeschik <hidden>
Date: 2020-08-03 05:45:07
Subsystem:
ethernet phy library, networking drivers, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Andrew Lunn <andrew@lunn.ch> SMI0 is a mangled version of MDIO. The main low level difference is the MDIO C22 OP code is always 0, not 0x2 or 0x1 for Read/Write. The read/write information is instead encoded in the PHY address. Extend the bit-bang code to allow the op code to be overridden, but default to normal C22 values. Add an extra compatible to the mdio-gpio driver, and when this compatible is present, set the op codes to 0. A higher level driver, sitting on top of the basic MDIO bus driver can then implement the rest of the microchip SMI0 odderties. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Michael Grzeschik <redacted> --- v1 -> v2: - patch not present v2 -> v3: - first patch v3 -> v4: - added override_c22_op drivers/net/phy/mdio-bitbang.c | 8 ++++++-- drivers/net/phy/mdio-gpio.c | 9 +++++++++ include/linux/mdio-bitbang.h | 3 +++ 3 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/drivers/net/phy/mdio-bitbang.c b/drivers/net/phy/mdio-bitbang.c
index 5136275c8e7399f..528e255d1ffe77f 100644
--- a/drivers/net/phy/mdio-bitbang.c
+++ b/drivers/net/phy/mdio-bitbang.c@@ -158,7 +158,7 @@ static int mdiobb_read(struct mii_bus *bus, int phy, int reg) reg = mdiobb_cmd_addr(ctrl, phy, reg); mdiobb_cmd(ctrl, MDIO_C45_READ, phy, reg); } else - mdiobb_cmd(ctrl, MDIO_READ, phy, reg); + mdiobb_cmd(ctrl, ctrl->op_c22_read, phy, reg); ctrl->ops->set_mdio_dir(ctrl, 0);
@@ -189,7 +189,7 @@ static int mdiobb_write(struct mii_bus *bus, int phy, int reg, u16 val) reg = mdiobb_cmd_addr(ctrl, phy, reg); mdiobb_cmd(ctrl, MDIO_C45_WRITE, phy, reg); } else - mdiobb_cmd(ctrl, MDIO_WRITE, phy, reg); + mdiobb_cmd(ctrl, ctrl->op_c22_write, phy, reg); /* send the turnaround (10) */ mdiobb_send_bit(ctrl, 1);
@@ -215,6 +215,10 @@ struct mii_bus *alloc_mdio_bitbang(struct mdiobb_ctrl *ctrl) bus->read = mdiobb_read; bus->write = mdiobb_write; bus->priv = ctrl; + if (!ctrl->override_op_c22) { + ctrl->op_c22_read = MDIO_READ; + ctrl->op_c22_write = MDIO_WRITE; + } return bus; }
diff --git a/drivers/net/phy/mdio-gpio.c b/drivers/net/phy/mdio-gpio.c
index 1b00235d7dc5b56..e8d83cee1bc17e1 100644
--- a/drivers/net/phy/mdio-gpio.c
+++ b/drivers/net/phy/mdio-gpio.c@@ -132,6 +132,14 @@ static struct mii_bus *mdio_gpio_bus_init(struct device *dev, new_bus->phy_ignore_ta_mask = pdata->phy_ignore_ta_mask; } + if (dev->of_node && + of_device_is_compatible(dev->of_node, "microchip,mdio-smi0")) { + bitbang->ctrl.op_c22_read = 0; + bitbang->ctrl.op_c22_write = 0; + } else { + bitbang->ctrl.override_op_c22 = 1; + } + dev_set_drvdata(dev, new_bus); return new_bus;
@@ -196,6 +204,7 @@ static int mdio_gpio_remove(struct platform_device *pdev) static const struct of_device_id mdio_gpio_of_match[] = { { .compatible = "virtual,mdio-gpio", }, + { .compatible = "microchip,mdio-smi0" }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, mdio_gpio_of_match);
diff --git a/include/linux/mdio-bitbang.h b/include/linux/mdio-bitbang.h
index 5d71e8a8500f5ed..5016e6f60de38af 100644
--- a/include/linux/mdio-bitbang.h
+++ b/include/linux/mdio-bitbang.h@@ -33,6 +33,9 @@ struct mdiobb_ops { struct mdiobb_ctrl { const struct mdiobb_ops *ops; + unsigned int override_op_c22; + u8 op_c22_read; + u8 op_c22_write; }; /* The returned bus is not yet registered with the phy layer. */
--
2.28.0