linux/drivers/net/phy/smsc.c
Dejin Zheng 6d61f483f1 net: phy: smsc: fix printing too many logs
Commit 7ae7ad2f11 ("net: phy: smsc: use phy_read_poll_timeout()
to simplify the code") will print a lot of logs as follows when Ethernet
cable is not connected:

[    4.473105] SMSC LAN8710/LAN8720 2188000.ethernet-1:00: lan87xx_read_status failed: -110

When wait 640 ms for check ENERGYON bit, the timeout should not be
regarded as an actual error and an error message also should not be
printed. due to a hardware bug in LAN87XX device, it leads to unstable
detection of plugging in Ethernet cable when LAN87xx is in Energy Detect
Power-Down mode. the workaround for it involves, when the link is down,
and at each read_status() call:

- disable EDPD mode, forcing the PHY out of low-power mode
- waiting 640ms to see if we have any energy detected from the media
- re-enable entry to EDPD mode

This is presumably enough to allow the PHY to notice that a cable is
connected, and resume normal operations to negotiate with the partner.
The problem is that when no media is detected, the 640ms wait times
out and this commit was modified to prints an error message. it is an
inappropriate conversion by used phy_read_poll_timeout() to introduce
this bug. so fix this issue by use read_poll_timeout() to replace
phy_read_poll_timeout().

Fixes: 7ae7ad2f11 ("net: phy: smsc: use phy_read_poll_timeout() to simplify the code")
Reported-by: Kevin Groeneveld <kgroeneveld@gmail.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-22 16:08:48 -07:00

366 lines
8.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* drivers/net/phy/smsc.c
*
* Driver for SMSC PHYs
*
* Author: Herbert Valerio Riedel
*
* Copyright (c) 2006 Herbert Valerio Riedel <hvr@gnu.org>
*
* Support added for SMSC LAN8187 and LAN8700 by steve.glendinning@shawell.net
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/of.h>
#include <linux/phy.h>
#include <linux/netdevice.h>
#include <linux/smscphy.h>
struct smsc_hw_stat {
const char *string;
u8 reg;
u8 bits;
};
static struct smsc_hw_stat smsc_hw_stats[] = {
{ "phy_symbol_errors", 26, 16},
};
struct smsc_phy_priv {
bool energy_enable;
};
static int smsc_phy_config_intr(struct phy_device *phydev)
{
int rc = phy_write (phydev, MII_LAN83C185_IM,
((PHY_INTERRUPT_ENABLED == phydev->interrupts)
? MII_LAN83C185_ISF_INT_PHYLIB_EVENTS
: 0));
return rc < 0 ? rc : 0;
}
static int smsc_phy_ack_interrupt(struct phy_device *phydev)
{
int rc = phy_read (phydev, MII_LAN83C185_ISF);
return rc < 0 ? rc : 0;
}
static int smsc_phy_config_init(struct phy_device *phydev)
{
struct smsc_phy_priv *priv = phydev->priv;
int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
if (priv->energy_enable) {
/* Enable energy detect mode for this SMSC Transceivers */
rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
rc | MII_LAN83C185_EDPWRDOWN);
if (rc < 0)
return rc;
}
return smsc_phy_ack_interrupt(phydev);
}
static int smsc_phy_reset(struct phy_device *phydev)
{
int rc = phy_read(phydev, MII_LAN83C185_SPECIAL_MODES);
if (rc < 0)
return rc;
/* If the SMSC PHY is in power down mode, then set it
* in all capable mode before using it.
*/
if ((rc & MII_LAN83C185_MODE_MASK) == MII_LAN83C185_MODE_POWERDOWN) {
/* set "all capable" mode */
rc |= MII_LAN83C185_MODE_ALL;
phy_write(phydev, MII_LAN83C185_SPECIAL_MODES, rc);
}
/* reset the phy */
return genphy_soft_reset(phydev);
}
static int lan911x_config_init(struct phy_device *phydev)
{
return smsc_phy_ack_interrupt(phydev);
}
/*
* The LAN87xx suffers from rare absence of the ENERGYON-bit when Ethernet cable
* plugs in while LAN87xx is in Energy Detect Power-Down mode. This leads to
* unstable detection of plugging in Ethernet cable.
* This workaround disables Energy Detect Power-Down mode and waiting for
* response on link pulses to detect presence of plugged Ethernet cable.
* The Energy Detect Power-Down mode is enabled again in the end of procedure to
* save approximately 220 mW of power if cable is unplugged.
*/
static int lan87xx_read_status(struct phy_device *phydev)
{
struct smsc_phy_priv *priv = phydev->priv;
int err = genphy_read_status(phydev);
if (!phydev->link && priv->energy_enable) {
/* Disable EDPD to wake up PHY */
int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
rc & ~MII_LAN83C185_EDPWRDOWN);
if (rc < 0)
return rc;
/* Wait max 640 ms to detect energy and the timeout is not
* an actual error.
*/
read_poll_timeout(phy_read, rc,
rc & MII_LAN83C185_ENERGYON || rc < 0,
10000, 640000, true, phydev,
MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
/* Re-enable EDPD */
rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
if (rc < 0)
return rc;
rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
rc | MII_LAN83C185_EDPWRDOWN);
if (rc < 0)
return rc;
}
return err;
}
static int smsc_get_sset_count(struct phy_device *phydev)
{
return ARRAY_SIZE(smsc_hw_stats);
}
static void smsc_get_strings(struct phy_device *phydev, u8 *data)
{
int i;
for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++) {
strncpy(data + i * ETH_GSTRING_LEN,
smsc_hw_stats[i].string, ETH_GSTRING_LEN);
}
}
static u64 smsc_get_stat(struct phy_device *phydev, int i)
{
struct smsc_hw_stat stat = smsc_hw_stats[i];
int val;
u64 ret;
val = phy_read(phydev, stat.reg);
if (val < 0)
ret = U64_MAX;
else
ret = val;
return ret;
}
static void smsc_get_stats(struct phy_device *phydev,
struct ethtool_stats *stats, u64 *data)
{
int i;
for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++)
data[i] = smsc_get_stat(phydev, i);
}
static int smsc_phy_probe(struct phy_device *phydev)
{
struct device *dev = &phydev->mdio.dev;
struct device_node *of_node = dev->of_node;
struct smsc_phy_priv *priv;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->energy_enable = true;
if (of_property_read_bool(of_node, "smsc,disable-energy-detect"))
priv->energy_enable = false;
phydev->priv = priv;
return 0;
}
static struct phy_driver smsc_phy_driver[] = {
{
.phy_id = 0x0007c0a0, /* OUI=0x00800f, Model#=0x0a */
.phy_id_mask = 0xfffffff0,
.name = "SMSC LAN83C185",
/* PHY_BASIC_FEATURES */
.probe = smsc_phy_probe,
/* basic functions */
.config_init = smsc_phy_config_init,
.soft_reset = smsc_phy_reset,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,
.config_intr = smsc_phy_config_intr,
.suspend = genphy_suspend,
.resume = genphy_resume,
}, {
.phy_id = 0x0007c0b0, /* OUI=0x00800f, Model#=0x0b */
.phy_id_mask = 0xfffffff0,
.name = "SMSC LAN8187",
/* PHY_BASIC_FEATURES */
.probe = smsc_phy_probe,
/* basic functions */
.config_init = smsc_phy_config_init,
.soft_reset = smsc_phy_reset,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,
.config_intr = smsc_phy_config_intr,
/* Statistics */
.get_sset_count = smsc_get_sset_count,
.get_strings = smsc_get_strings,
.get_stats = smsc_get_stats,
.suspend = genphy_suspend,
.resume = genphy_resume,
}, {
.phy_id = 0x0007c0c0, /* OUI=0x00800f, Model#=0x0c */
.phy_id_mask = 0xfffffff0,
.name = "SMSC LAN8700",
/* PHY_BASIC_FEATURES */
.probe = smsc_phy_probe,
/* basic functions */
.read_status = lan87xx_read_status,
.config_init = smsc_phy_config_init,
.soft_reset = smsc_phy_reset,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,
.config_intr = smsc_phy_config_intr,
/* Statistics */
.get_sset_count = smsc_get_sset_count,
.get_strings = smsc_get_strings,
.get_stats = smsc_get_stats,
.suspend = genphy_suspend,
.resume = genphy_resume,
}, {
.phy_id = 0x0007c0d0, /* OUI=0x00800f, Model#=0x0d */
.phy_id_mask = 0xfffffff0,
.name = "SMSC LAN911x Internal PHY",
/* PHY_BASIC_FEATURES */
.probe = smsc_phy_probe,
/* basic functions */
.config_init = lan911x_config_init,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,
.config_intr = smsc_phy_config_intr,
.suspend = genphy_suspend,
.resume = genphy_resume,
}, {
.phy_id = 0x0007c0f0, /* OUI=0x00800f, Model#=0x0f */
.phy_id_mask = 0xfffffff0,
.name = "SMSC LAN8710/LAN8720",
/* PHY_BASIC_FEATURES */
.flags = PHY_RST_AFTER_CLK_EN,
.probe = smsc_phy_probe,
/* basic functions */
.read_status = lan87xx_read_status,
.config_init = smsc_phy_config_init,
.soft_reset = smsc_phy_reset,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,
.config_intr = smsc_phy_config_intr,
/* Statistics */
.get_sset_count = smsc_get_sset_count,
.get_strings = smsc_get_strings,
.get_stats = smsc_get_stats,
.suspend = genphy_suspend,
.resume = genphy_resume,
}, {
.phy_id = 0x0007c110,
.phy_id_mask = 0xfffffff0,
.name = "SMSC LAN8740",
/* PHY_BASIC_FEATURES */
.flags = PHY_RST_AFTER_CLK_EN,
.probe = smsc_phy_probe,
/* basic functions */
.read_status = lan87xx_read_status,
.config_init = smsc_phy_config_init,
.soft_reset = smsc_phy_reset,
/* IRQ related */
.ack_interrupt = smsc_phy_ack_interrupt,
.config_intr = smsc_phy_config_intr,
/* Statistics */
.get_sset_count = smsc_get_sset_count,
.get_strings = smsc_get_strings,
.get_stats = smsc_get_stats,
.suspend = genphy_suspend,
.resume = genphy_resume,
} };
module_phy_driver(smsc_phy_driver);
MODULE_DESCRIPTION("SMSC PHY driver");
MODULE_AUTHOR("Herbert Valerio Riedel");
MODULE_LICENSE("GPL");
static struct mdio_device_id __maybe_unused smsc_tbl[] = {
{ 0x0007c0a0, 0xfffffff0 },
{ 0x0007c0b0, 0xfffffff0 },
{ 0x0007c0c0, 0xfffffff0 },
{ 0x0007c0d0, 0xfffffff0 },
{ 0x0007c0f0, 0xfffffff0 },
{ 0x0007c110, 0xfffffff0 },
{ }
};
MODULE_DEVICE_TABLE(mdio, smsc_tbl);