From 800fcab8230f622544a12403977b5b7259a076f8 Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Tue, 27 Apr 2021 09:09:07 +0200 Subject: [PATCH] net: phy: Add support for microchip SMI0 MDIO bus 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 Signed-off-by: Michael Grzeschik Signed-off-by: Oleksij Rempel Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/mdio/mdio-bitbang.c | 8 ++++++-- drivers/net/mdio/mdio-gpio.c | 8 ++++++++ include/linux/mdio-bitbang.h | 3 +++ 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/net/mdio/mdio-bitbang.c b/drivers/net/mdio/mdio-bitbang.c index 0f457c4..0760911 100644 --- a/drivers/net/mdio/mdio-bitbang.c +++ b/drivers/net/mdio/mdio-bitbang.c @@ -158,7 +158,7 @@ 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); @@ -190,7 +190,7 @@ 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); @@ -217,6 +217,10 @@ 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/mdio/mdio-gpio.c b/drivers/net/mdio/mdio-gpio.c index 56c8f91..0fb3c2d 100644 --- a/drivers/net/mdio/mdio-gpio.c +++ b/drivers/net/mdio/mdio-gpio.c @@ -132,6 +132,13 @@ 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; + bitbang->ctrl.override_op_c22 = 1; + } + dev_set_drvdata(dev, new_bus); return new_bus; @@ -196,6 +203,7 @@ 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 aca4dc0..373630f 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; }; int mdiobb_read(struct mii_bus *bus, int phy, int reg); -- 2.7.4