Hi Wolfram,
On Wed Mar 29, 2023 at 8:40 AM CEST, Wolfram Sang wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>
> Otherwise the clocks are not enabled and reading registers will OOPS.
> Copy the behaviour from Renesas SH_ETH and use a custom flag because
> using netif_running() is racy. A generic solution still needs to be
> implemented. Tested on a Renesas APE6-EK.
>
> Fixes: 1e30b8d755b8 ("net: smsc911x: Make Runtime PM handling more fine-grained")
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> Changes since v3:
> * broken out of a patch series
> * don't use netif_running() but a custom flag
>
> drivers/net/ethernet/smsc/smsc911x.c | 14 ++++++++++++--
> 1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c
> index a690d139e177..af96986cbc88 100644
> --- a/drivers/net/ethernet/smsc/smsc911x.c
> +++ b/drivers/net/ethernet/smsc/smsc911x.c
> @@ -140,6 +140,8 @@ struct smsc911x_data {
>
> /* clock */
> struct clk *clk;
> +
> + bool is_open;
> };
>
> /* Easy access to information */
> @@ -1738,6 +1740,8 @@ static int smsc911x_open(struct net_device *dev)
> smsc911x_reg_write(pdata, TX_CFG, TX_CFG_TX_ON_);
>
> netif_start_queue(dev);
> + pdata->is_open = true;
> +
> return 0;
>
> irq_stop_out:
> @@ -1778,6 +1782,8 @@ static int smsc911x_stop(struct net_device *dev)
> dev->phydev = NULL;
> }
> netif_carrier_off(dev);
> + pdata->is_open = false;
> +
> pm_runtime_put(dev->dev.parent);
>
> SMSC_TRACE(pdata, ifdown, "Interface stopped");
> @@ -1841,8 +1847,12 @@ smsc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
> static struct net_device_stats *smsc911x_get_stats(struct net_device *dev)
> {
> struct smsc911x_data *pdata = netdev_priv(dev);
> - smsc911x_tx_update_txcounters(dev);
> - dev->stats.rx_dropped += smsc911x_reg_read(pdata, RX_DROP);
> +
> + if (pdata->is_open) {
Couldn't you just use netif_carrier_ok() here and drop the is_open
variable?
> + smsc911x_tx_update_txcounters(dev);
> + dev->stats.rx_dropped += smsc911x_reg_read(pdata, RX_DROP);
> + }
> +
> return &dev->stats;
> }
>
> --
> 2.30.2
BR
Steen
