diff options
Diffstat (limited to 'target/linux/brcm63xx/patches-4.4/001-4.12-07-mdio_bus-Issue-GPIO-RESET-to-PHYs.patch')
| -rw-r--r-- | target/linux/brcm63xx/patches-4.4/001-4.12-07-mdio_bus-Issue-GPIO-RESET-to-PHYs.patch | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/target/linux/brcm63xx/patches-4.4/001-4.12-07-mdio_bus-Issue-GPIO-RESET-to-PHYs.patch b/target/linux/brcm63xx/patches-4.4/001-4.12-07-mdio_bus-Issue-GPIO-RESET-to-PHYs.patch new file mode 100644 index 0000000000..2deeb7b816 --- /dev/null +++ b/target/linux/brcm63xx/patches-4.4/001-4.12-07-mdio_bus-Issue-GPIO-RESET-to-PHYs.patch @@ -0,0 +1,192 @@ +From 69226896ad636b94f6d2e55d75ff21a29c4de83b Mon Sep 17 00:00:00 2001 +From: Roger Quadros <rogerq@ti.com> +Date: Fri, 21 Apr 2017 16:15:38 +0300 +Subject: [PATCH] mdio_bus: Issue GPIO RESET to PHYs. + +Some boards [1] leave the PHYs at an invalid state +during system power-up or reset thus causing unreliability +issues with the PHY which manifests as PHY not being detected +or link not functional. To fix this, these PHYs need to be RESET +via a GPIO connected to the PHY's RESET pin. + +Some boards have a single GPIO controlling the PHY RESET pin of all +PHYs on the bus whereas some others have separate GPIOs controlling +individual PHY RESETs. + +In both cases, the RESET de-assertion cannot be done in the PHY driver +as the PHY will not probe till its reset is de-asserted. +So do the RESET de-assertion in the MDIO bus driver. + +[1] - am572x-idk, am571x-idk, a437x-idk + +Signed-off-by: Roger Quadros <rogerq@ti.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + Documentation/devicetree/bindings/net/mdio.txt | 33 ++++++++++++++++++ + drivers/net/phy/mdio_bus.c | 47 ++++++++++++++++++++++++++ + drivers/of/of_mdio.c | 7 ++++ + include/linux/phy.h | 7 ++++ + 4 files changed, 94 insertions(+) + create mode 100644 Documentation/devicetree/bindings/net/mdio.txt + +--- /dev/null ++++ b/Documentation/devicetree/bindings/net/mdio.txt +@@ -0,0 +1,33 @@ ++Common MDIO bus properties. ++ ++These are generic properties that can apply to any MDIO bus. ++ ++Optional properties: ++- reset-gpios: List of one or more GPIOs that control the RESET lines ++ of the PHYs on that MDIO bus. ++- reset-delay-us: RESET pulse width in microseconds as per PHY datasheet. ++ ++A list of child nodes, one per device on the bus is expected. These ++should follow the generic phy.txt, or a device specific binding document. ++ ++Example : ++This example shows these optional properties, plus other properties ++required for the TI Davinci MDIO driver. ++ ++ davinci_mdio: ethernet@0x5c030000 { ++ compatible = "ti,davinci_mdio"; ++ reg = <0x5c030000 0x1000>; ++ #address-cells = <1>; ++ #size-cells = <0>; ++ ++ reset-gpios = <&gpio2 5 GPIO_ACTIVE_LOW>; ++ reset-delay-us = <2>; /* PHY datasheet states 1us min */ ++ ++ ethphy0: ethernet-phy@1 { ++ reg = <1>; ++ }; ++ ++ ethphy1: ethernet-phy@3 { ++ reg = <3>; ++ }; ++ }; +--- a/drivers/net/phy/mdio_bus.c ++++ b/drivers/net/phy/mdio_bus.c +@@ -22,8 +22,11 @@ + #include <linux/init.h> + #include <linux/delay.h> + #include <linux/device.h> ++#include <linux/gpio.h> ++#include <linux/gpio/consumer.h> + #include <linux/of_device.h> + #include <linux/of_mdio.h> ++#include <linux/of_gpio.h> + #include <linux/netdevice.h> + #include <linux/etherdevice.h> + #include <linux/skbuff.h> +@@ -252,6 +255,7 @@ static inline void of_mdiobus_link_phyde + int __mdiobus_register(struct mii_bus *bus, struct module *owner) + { + int i, err; ++ struct gpio_desc *gpiod; + + if (NULL == bus || NULL == bus->name || + NULL == bus->read || NULL == bus->write) +@@ -278,6 +282,35 @@ int __mdiobus_register(struct mii_bus *b + if (bus->reset) + bus->reset(bus); + ++ /* de-assert bus level PHY GPIO resets */ ++ if (bus->num_reset_gpios > 0) { ++ bus->reset_gpiod = devm_kcalloc(&bus->dev, ++ bus->num_reset_gpios, ++ sizeof(struct gpio_desc *), ++ GFP_KERNEL); ++ if (!bus->reset_gpiod) ++ return -ENOMEM; ++ } ++ ++ for (i = 0; i < bus->num_reset_gpios; i++) { ++ gpiod = devm_gpiod_get_index(&bus->dev, "reset", i, ++ GPIOD_OUT_LOW); ++ if (IS_ERR(gpiod)) { ++ err = PTR_ERR(gpiod); ++ if (err != -ENOENT) { ++ dev_err(&bus->dev, ++ "mii_bus %s couldn't get reset GPIO\n", ++ bus->id); ++ return err; ++ } ++ } else { ++ bus->reset_gpiod[i] = gpiod; ++ gpiod_set_value_cansleep(gpiod, 1); ++ udelay(bus->reset_delay_us); ++ gpiod_set_value_cansleep(gpiod, 0); ++ } ++ } ++ + for (i = 0; i < PHY_MAX_ADDR; i++) { + if ((bus->phy_mask & (1 << i)) == 0) { + struct phy_device *phydev; +@@ -302,6 +335,13 @@ error: + phy_device_free(phydev); + } + } ++ ++ /* Put PHYs in RESET to save power */ ++ for (i = 0; i < bus->num_reset_gpios; i++) { ++ if (bus->reset_gpiod[i]) ++ gpiod_set_value_cansleep(bus->reset_gpiod[i], 1); ++ } ++ + device_del(&bus->dev); + return err; + } +@@ -321,6 +361,13 @@ void mdiobus_unregister(struct mii_bus * + phy_device_free(phydev); + } + } ++ ++ /* Put PHYs in RESET to save power */ ++ for (i = 0; i < bus->num_reset_gpios; i++) { ++ if (bus->reset_gpiod[i]) ++ gpiod_set_value_cansleep(bus->reset_gpiod[i], 1); ++ } ++ + device_del(&bus->dev); + } + EXPORT_SYMBOL(mdiobus_unregister); +--- a/drivers/of/of_mdio.c ++++ b/drivers/of/of_mdio.c +@@ -21,6 +21,8 @@ + #include <linux/of_mdio.h> + #include <linux/module.h> + ++#define DEFAULT_GPIO_RESET_DELAY 10 /* in microseconds */ ++ + MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); + MODULE_LICENSE("GPL"); + +@@ -140,6 +142,11 @@ int of_mdiobus_register(struct mii_bus * + + mdio->dev.of_node = np; + ++ /* Get bus level PHY reset GPIO details */ ++ mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY; ++ of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us); ++ mdio->num_reset_gpios = of_gpio_named_count(np, "reset-gpios"); ++ + /* Register the MDIO bus */ + rc = mdiobus_register(mdio); + if (rc) +--- a/include/linux/phy.h ++++ b/include/linux/phy.h +@@ -191,6 +191,13 @@ struct mii_bus { + * interrupt at the index matching its address + */ + int *irq; ++ ++ /* GPIO reset pulse width in microseconds */ ++ int reset_delay_us; ++ /* Number of reset GPIOs */ ++ int num_reset_gpios; ++ /* Array of RESET GPIO descriptors */ ++ struct gpio_desc **reset_gpiod; + }; + #define to_mii_bus(d) container_of(d, struct mii_bus, dev) + |