From: Richard Leitner <richard.leitner@xxxxxxxxxxx> Some PHYs need a minimum time after the reset gpio was asserted and/or deasserted. To ensure we meet these timing requirements add two new optional devicetree parameters for the phy: reset-delay-us and reset-post-delay-us. This patch depends on the "phylib: Add device reset GPIO support" patch submitted by Geert Uytterhoeven/Sergei Shtylyov, see: https://patchwork.kernel.org/patch/10090149/ Signed-off-by: Richard Leitner <richard.leitner@xxxxxxxxxxx> --- Documentation/devicetree/bindings/net/phy.txt | 10 ++++++++++ drivers/net/phy/mdio_device.c | 13 +++++++++++-- drivers/of/of_mdio.c | 8 ++++++++ include/linux/mdio.h | 2 ++ 4 files changed, 31 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/net/phy.txt b/Documentation/devicetree/bindings/net/phy.txt index c05479f5ac7c..72860ce7f610 100644 --- a/Documentation/devicetree/bindings/net/phy.txt +++ b/Documentation/devicetree/bindings/net/phy.txt @@ -55,6 +55,12 @@ Optional Properties: - reset-gpios: The GPIO phandle and specifier for the PHY reset signal. +- reset-delay-us: Delay after the reset was asserted in microseconds. + If this property is missing the delay will be skipped. + +- reset-post-delay-us: Delay after the reset was deasserted in microseconds. + If this property is missing the delay will be skipped. + Example: ethernet-phy@0 { @@ -62,4 +68,8 @@ ethernet-phy@0 { interrupt-parent = <&PIC>; interrupts = <35 IRQ_TYPE_EDGE_RISING>; reg = <0>; + + reset-gpios = <&gpio1 4 GPIO_ACTIVE_LOW>; + reset-delay-us = <1000>; + reset-post-delay-us = <2000>; }; diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c index 75d97dd9fb28..ca3ff43f8ee8 100644 --- a/drivers/net/phy/mdio_device.c +++ b/drivers/net/phy/mdio_device.c @@ -24,6 +24,7 @@ #include <linux/slab.h> #include <linux/string.h> #include <linux/unistd.h> +#include <linux/delay.h> void mdio_device_free(struct mdio_device *mdiodev) { @@ -118,8 +119,16 @@ EXPORT_SYMBOL(mdio_device_remove); void mdio_device_reset(struct mdio_device *mdiodev, int value) { - if (mdiodev->reset) - gpiod_set_value(mdiodev->reset, value); + if (!mdiodev->reset) + return; + + gpiod_set_value(mdiodev->reset, value); + + if (value && mdiodev->reset_delay) + usleep_range(mdiodev->reset_delay, mdiodev->reset_delay + 100); + else if (!value && mdiodev->reset_post_delay) + usleep_range(mdiodev->reset_post_delay, + mdiodev->reset_post_delay + 100); } EXPORT_SYMBOL(mdio_device_reset); diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c index 98258583abb0..fb56486dfaa0 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -77,6 +77,14 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio, if (of_property_read_bool(child, "broken-turn-around")) mdio->phy_ignore_ta_mask |= 1 << addr; + if (of_property_read_u32(child, "reset-delay-us", + &phy->mdio.reset_delay)) + phy->mdio.reset_delay = 0; + + if (of_property_read_u32(child, "reset-post-delay-us", + &phy->mdio.reset_post_delay)) + phy->mdio.reset_post_delay = 0; + /* Associate the OF node with the device structure so it * can be looked up later */ of_node_get(child); diff --git a/include/linux/mdio.h b/include/linux/mdio.h index 92d4e55ffe67..e37c21d8eb19 100644 --- a/include/linux/mdio.h +++ b/include/linux/mdio.h @@ -41,6 +41,8 @@ struct mdio_device { int addr; int flags; struct gpio_desc *reset; + unsigned int reset_delay; + unsigned int reset_post_delay; }; #define to_mdio_device(d) container_of(d, struct mdio_device, dev) -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
