[PATCH 3/3] net: fec: Reset ethernet PHY whenever the enet_out clock is being enabled
From: Lothar Waßmann <hidden>
Date: 2015-11-30 11:34:42
Also in:
lkml
Subsystem:
freescale imx / mxc fec driver, networking drivers, the rest · Maintainers:
Wei Fang, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
If a PHY uses ENET_OUT as reference clock, it may need a RESET to get functional after the clock had been disabled. Failure to do this results in the link state constantly toggling between up and down: fec 02188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx fec 02188000.ethernet eth0: Link is Down fec 02188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx fec 02188000.ethernet eth0: Link is Down [...] Signed-off-by: Lothar Waßmann <redacted> --- drivers/net/ethernet/freescale/fec.h | 1 + drivers/net/ethernet/freescale/fec_main.c | 46 ++++++++++++++++++++++++------- 2 files changed, 37 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 99d33e2..8ab4f7f 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h@@ -519,6 +519,7 @@ struct fec_enet_private { int pause_flag; int wol_flag; u32 quirks; + struct gpio_desc *phy_reset; struct napi_struct napi; int csum_flags;
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 1a983fc..7ba2bbb 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c@@ -66,6 +66,7 @@ static void set_multicast_list(struct net_device *ndev); static void fec_enet_itr_coal_init(struct net_device *ndev); +static void fec_reset_phy(struct platform_device *pdev); #define DRIVER_NAME "fec"
@@ -1861,6 +1862,8 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable) ret = clk_prepare_enable(fep->clk_enet_out); if (ret) goto failed_clk_enet_out; + + fec_reset_phy(fep->pdev); } if (fep->clk_ptp) { mutex_lock(&fep->ptp_clk_mutex);
@@ -3231,13 +3234,32 @@ static int fec_enet_init(struct net_device *ndev) } #ifdef CONFIG_OF -static void fec_reset_phy(struct platform_device *pdev) +static struct gpio_desc *fec_get_reset_gpio(struct platform_device *pdev) { struct gpio_desc *phy_reset; - int msec = 1; struct device_node *np = pdev->dev.of_node; if (!np) + return ERR_PTR(-ENODEV); + + phy_reset = devm_gpiod_get_optional(&pdev->dev, "phy-reset", + GPIOD_OUT_LOW); + if (IS_ERR(phy_reset)) + dev_err(&pdev->dev, "failed to get phy-reset-gpios: %ld\n", + PTR_ERR(phy_reset)); + return phy_reset; +} + +static void fec_reset_phy(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct net_device *ndev = platform_get_drvdata(pdev); + struct fec_enet_private *fep = netdev_priv(ndev); + int msec = 1; + + if (!fep->phy_reset) + return; + if (!np) return; of_property_read_u32(np, "phy-reset-duration", &msec);
@@ -3245,17 +3267,16 @@ static void fec_reset_phy(struct platform_device *pdev) if (msec > 1000) msec = 1; - phy_reset = devm_gpiod_get_optional(&pdev->dev, "phy-reset", - GPIOD_OUT_LOW); - if (IS_ERR(phy_reset)) { - dev_err(&pdev->dev, "failed to get phy-reset-gpios: %ld\n", - PTR_ERR(phy_reset)); - return; - } + gpiod_set_value_cansleep(fep->phy_reset, 0); msleep(msec); - gpiod_set_value_cansleep(phy_reset, 1); + gpiod_set_value_cansleep(fep->phy_reset, 1); } #else /* CONFIG_OF */ +static void fec_get_reset_gpio(struct platform_device *pdev) +{ + return -EINVAL; +} + static void fec_reset_phy(struct platform_device *pdev) { /*
@@ -3309,8 +3330,12 @@ fec_probe(struct platform_device *pdev) struct device_node *np = pdev->dev.of_node, *phy_node; int num_tx_qs; int num_rx_qs; + struct gpio_desc *phy_reset; fec_enet_get_queue_num(pdev, &num_tx_qs, &num_rx_qs); + phy_reset = fec_get_reset_gpio(pdev); + if (IS_ERR(phy_reset) && PTR_ERR(phy_reset) == -EPROBE_DEFER) + return -EPROBE_DEFER; /* Init network device */ ndev = alloc_etherdev_mqs(sizeof(struct fec_enet_private),
@@ -3331,6 +3356,7 @@ fec_probe(struct platform_device *pdev) fep->netdev = ndev; fep->num_rx_queues = num_rx_qs; fep->num_tx_queues = num_tx_qs; + fep->phy_reset = phy_reset; #if !defined(CONFIG_M5272) /* default enable pause frame auto negotiation */
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2.1.4