Re: [PATCH net-next v2] net: dsa: realtek: realtek-mdio: reset before setup
From: Arınç ÜNAL <hidden>
Date: 2022-02-12 02:48:18
On 12 Feb 2022, at 05:27, Luiz Angelo Daros de Luca [off-list ref] wrote: Some devices, like the switch in Banana Pi BPI R64 only starts to answer after a HW reset. It is the same reset code from realtek-smi. In realtek-smi, only assert the reset when the gpio is defined.
If realtek-smi also resets before setup with this patch (I don’t understand code very well) can you mention it next to mdio in the summary too? In any case: Acked-by: Arınç ÜNAL <redacted>
quoted hunk
Reported-by: Frank Wunderlich <redacted> Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Tested-by: Frank Wunderlich <redacted> Reviewed-by: Linus Walleij <redacted> Reviewed-by: Alvin Šipraga <redacted> --- drivers/net/dsa/realtek/realtek-mdio.c | 19 +++++++++++++++++++ drivers/net/dsa/realtek/realtek-smi.c | 17 ++++++++++------- drivers/net/dsa/realtek/realtek.h | 3 +++ 3 files changed, 32 insertions(+), 7 deletions(-)diff --git a/drivers/net/dsa/realtek/realtek-mdio.c b/drivers/net/dsa/realtek/realtek-mdio.c index 0c5f2bdced9d..fa2339763c71 100644 --- a/drivers/net/dsa/realtek/realtek-mdio.c +++ b/drivers/net/dsa/realtek/realtek-mdio.c@@ -152,6 +152,21 @@ static int realtek_mdio_probe(struct mdio_device *mdiodev) /* TODO: if power is software controlled, set up any regulators here */ priv->leds_disabled = of_property_read_bool(np, "realtek,disable-leds"); + /* Assert then deassert RESET */ + priv->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(priv->reset)) { + dev_err(dev, "failed to get RESET GPIO\n"); + return PTR_ERR(priv->reset); + } + + if (priv->reset) { + dev_dbg(dev, "asserted RESET\n"); + msleep(REALTEK_HW_STOP_DELAY); + gpiod_set_value(priv->reset, 0); + msleep(REALTEK_HW_START_DELAY); + dev_dbg(dev, "deasserted RESET\n"); + } + ret = priv->ops->detect(priv); if (ret) { dev_err(dev, "unable to detect switch\n");@@ -185,6 +200,10 @@ static void realtek_mdio_remove(struct mdio_device *mdiodev) dsa_unregister_switch(priv->ds); + /* leave the device reset asserted */ + if (priv->reset) + gpiod_set_value(priv->reset, 1); + dev_set_drvdata(&mdiodev->dev, NULL);}diff --git a/drivers/net/dsa/realtek/realtek-smi.c b/drivers/net/dsa/realtek/realtek-smi.c index 946fbbd70153..a13ef07080a2 100644 --- a/drivers/net/dsa/realtek/realtek-smi.c +++ b/drivers/net/dsa/realtek/realtek-smi.c@@ -43,8 +43,6 @@#include "realtek.h" #define REALTEK_SMI_ACK_RETRY_COUNT 5 -#define REALTEK_SMI_HW_STOP_DELAY 25 /* msecs */ -#define REALTEK_SMI_HW_START_DELAY 100 /* msecs */ static inline void realtek_smi_clk_delay(struct realtek_priv *priv) {@@ -426,10 +424,13 @@ static int realtek_smi_probe(struct platform_device *pdev) dev_err(dev, "failed to get RESET GPIO\n"); return PTR_ERR(priv->reset); } - msleep(REALTEK_SMI_HW_STOP_DELAY); - gpiod_set_value(priv->reset, 0); - msleep(REALTEK_SMI_HW_START_DELAY); - dev_info(dev, "deasserted RESET\n"); + if (priv->reset) { + dev_dbg(dev, "asserted RESET\n"); + msleep(REALTEK_HW_STOP_DELAY); + gpiod_set_value(priv->reset, 0); + msleep(REALTEK_HW_START_DELAY); + dev_dbg(dev, "deasserted RESET\n"); + } /* Fetch MDIO pins */ priv->mdc = devm_gpiod_get_optional(dev, "mdc", GPIOD_OUT_LOW);@@ -474,7 +475,9 @@ static int realtek_smi_remove(struct platform_device *pdev) dsa_unregister_switch(priv->ds); if (priv->slave_mii_bus) of_node_put(priv->slave_mii_bus->dev.of_node); - gpiod_set_value(priv->reset, 1); + + if (priv->reset) + gpiod_set_value(priv->reset, 1); platform_set_drvdata(pdev, NULL);diff --git a/drivers/net/dsa/realtek/realtek.h b/drivers/net/dsa/realtek/realtek.h index 3512b832b148..e7d3e1bcf8b8 100644 --- a/drivers/net/dsa/realtek/realtek.h +++ b/drivers/net/dsa/realtek/realtek.h@@ -13,6 +13,9 @@#include <linux/gpio/consumer.h> #include <net/dsa.h> +#define REALTEK_HW_STOP_DELAY 25 /* msecs */ +#define REALTEK_HW_START_DELAY 100 /* msecs */ + struct realtek_ops; struct dentry; struct inode; -- 2.35.1