Commit f4c7d894 authored by Biao Huang's avatar Biao Huang Committed by David S. Miller
Browse files

net: stmmac: fix unbalanced ptp clock issue in suspend/resume flow 



Current stmmac driver will prepare/enable ptp_ref clock in
stmmac_init_tstamp_counter().

The stmmac_pltfr_noirq_suspend will disable it once in suspend flow.

But in resume flow,
	stmmac_pltfr_noirq_resume --> stmmac_init_tstamp_counter
	stmmac_resume --> stmmac_hw_setup --> stmmac_init_ptp --> stmmac_init_tstamp_counter
ptp_ref clock reference counter increases twice, which leads to unbalance
ptp clock when resume back.

Move ptp_ref clock prepare/enable out of stmmac_init_tstamp_counter to fix it.

Fixes: 0735e639 ("net: stmmac: skip only stmmac_ptp_register when resume from suspend")
Signed-off-by: default avatarBiao Huang <biao.huang@mediatek.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0d9a1591

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

+8 −9
Original line number Diff line number Diff line
@@ -834,19 +834,10 @@ int stmmac_init_tstamp_counter(struct stmmac_priv *priv, u32 systime_flags) 
	struct timespec64 now;

	u32 sec_inc = 0;

	u64 temp = 0;

	int ret;



	if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))

		return -EOPNOTSUPP;



	ret = clk_prepare_enable(priv->plat->clk_ptp_ref);

	if (ret < 0) {

		netdev_warn(priv->dev,

			    "failed to enable PTP reference clock: %pe\n",

			    ERR_PTR(ret));

		return ret;

	}



	stmmac_config_hw_tstamping(priv, priv->ptpaddr, systime_flags);

	priv->systime_flags = systime_flags;
@@ -3270,6 +3261,14 @@ static int stmmac_hw_setup(struct net_device *dev, bool ptp_register) 


	stmmac_mmc_setup(priv);



	if (ptp_register) {

		ret = clk_prepare_enable(priv->plat->clk_ptp_ref);

		if (ret < 0)

			netdev_warn(priv->dev,

				    "failed to enable PTP reference clock: %pe\n",

				    ERR_PTR(ret));

	}



	ret = stmmac_init_ptp(priv);

	if (ret == -EOPNOTSUPP)

		netdev_info(priv->dev, "PTP not supported by HW\n");

drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c

+7 −1
Original line number Diff line number Diff line
@@ -815,7 +815,13 @@ static int __maybe_unused stmmac_pltfr_noirq_resume(struct device *dev) 
		if (ret)

			return ret;



		stmmac_init_tstamp_counter(priv, priv->systime_flags);

		ret = clk_prepare_enable(priv->plat->clk_ptp_ref);

		if (ret < 0) {

			netdev_warn(priv->dev,

				    "failed to enable PTP reference clock: %pe\n",

				    ERR_PTR(ret));

			return ret;

		}

	}



	return 0;