Merge branch 'dsa-gpio-reset' Andrew Lunn says: ==================== DSA: GPIO to reset switches These two patches add support for using a GPIO to hard reset a switch during reset. v2: Thanks to a clue from Neil Armstrong, i figured out how to convert the gpio into a gpiod, while keeping the ACTIVE_LOW flag, so simplifiying the set/reset code. I have not included the Tested-by: from Phil Reid, since i made a lot of changes. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.txt b/Documentation/devicetree/bindings/net/dsa/dsa.txt index 04e6bef..5fdbbcd 100644 --- a/Documentation/devicetree/bindings/net/dsa/dsa.txt +++ b/Documentation/devicetree/bindings/net/dsa/dsa.txt
@@ -31,6 +31,8 @@ switch. Must be set if the switch can not detect the presence and/or size of a connected EEPROM, otherwise optional. +- reset-gpios : phandle and specifier to a gpio line connected to + reset pin of the switch chip. A switch may have multiple "port" children nodes @@ -114,6 +116,7 @@ #size-cells = <0>; reg = <17 1>; /* MDIO address 17, switch 1 in tree */ mii-bus = <&mii_bus1>; + reset-gpios = <&gpio5 1 GPIO_ACTIVE_LOW>; switch1port0: port@0 { reg = <0>;
diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c index b06dba0..75e245c 100644 --- a/drivers/net/dsa/mv88e6xxx.c +++ b/drivers/net/dsa/mv88e6xxx.c
@@ -19,6 +19,7 @@ #include <linux/list.h> #include <linux/module.h> #include <linux/netdevice.h> +#include <linux/gpio/consumer.h> #include <linux/phy.h> #include <net/dsa.h> #include <net/switchdev.h> @@ -2323,6 +2324,7 @@ { struct mv88e6xxx_priv_state *ps = ds_to_priv(ds); u16 is_reset = (ppu_active ? 0x8800 : 0xc800); + struct gpio_desc *gpiod = ds->pd->reset; unsigned long timeout; int ret; int i; @@ -2336,6 +2338,14 @@ /* Wait for transmit queues to drain. */ usleep_range(2000, 4000); + /* If there is a gpio connected to the reset pin, toggle it */ + if (gpiod) { + gpiod_set_value_cansleep(gpiod, 1); + usleep_range(10000, 20000); + gpiod_set_value_cansleep(gpiod, 0); + usleep_range(10000, 20000); + } + /* Reset the switch. Keep the PPU active if requested. The PPU * needs to be active to support indirect phy register access * through global registers 0x18 and 0x19.
diff --git a/include/net/dsa.h b/include/net/dsa.h index 82a4c60..3f23dd9 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h
@@ -16,6 +16,7 @@ #include <linux/timer.h> #include <linux/workqueue.h> #include <linux/of.h> +#include <linux/of_gpio.h> #include <linux/phy.h> #include <linux/phy_fixed.h> #include <linux/ethtool.h> @@ -64,6 +65,13 @@ * NULL if there is only one switch chip. */ s8 *rtable; + + /* + * A switch may have a GPIO line tied to its reset pin. Parse + * this from the device tree, and use it before performing + * switch soft reset. + */ + struct gpio_desc *reset; }; struct dsa_platform_data {
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c index 1eba07f..0b5565f 100644 --- a/net/dsa/dsa.c +++ b/net/dsa/dsa.c
@@ -21,6 +21,7 @@ #include <linux/of_mdio.h> #include <linux/of_platform.h> #include <linux/of_net.h> +#include <linux/of_gpio.h> #include <linux/sysfs.h> #include <linux/phy_fixed.h> #include "dsa_priv.h" @@ -688,6 +689,9 @@ const char *port_name; int chip_index, port_index; const unsigned int *sw_addr, *port_reg; + int gpio; + enum of_gpio_flags of_flags; + unsigned long flags; u32 eeprom_len; int ret; @@ -766,6 +770,19 @@ put_device(cd->host_dev); cd->host_dev = &mdio_bus_switch->dev; } + gpio = of_get_named_gpio_flags(child, "reset-gpios", 0, + &of_flags); + if (gpio_is_valid(gpio)) { + flags = (of_flags == OF_GPIO_ACTIVE_LOW ? + GPIOF_ACTIVE_LOW : 0); + ret = devm_gpio_request_one(dev, gpio, flags, + "switch_reset"); + if (ret) + goto out_free_chip; + + cd->reset = gpio_to_desc(gpio); + gpiod_direction_output(cd->reset, 0); + } for_each_available_child_of_node(child, port) { port_reg = of_get_property(port, "reg", NULL);