| Message ID | 20170505114646.1278-2-quentin.schulz@free-electrons.com |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On 05/05/2017 01:46 PM, Quentin Schulz wrote: > This adds Power Management deep Suspend/Resume support for Bosch M_CAN > chip. > > When entering deep sleep, the clocks are gated, the interrupts are > disabled. When resuming from deep sleep, the chip needs to be > reinitialized, the clocks ungated and the interrupts enabled. > > Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> > --- > > v3: > - do not close/reopen the can interface (which was previously done when > calling m_can_close), basically do the same routine as in probe but > it does not close/open the can device, much better! > - update commit log, > > v2: > - fix erroneous commit log, > > drivers/net/can/m_can/m_can.c | 17 ++++++++++++++--- > 1 file changed, 14 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c > index 3f0445440146..0a06690febe2 100644 > --- a/drivers/net/can/m_can/m_can.c > +++ b/drivers/net/can/m_can/m_can.c > @@ -1672,10 +1672,9 @@ static __maybe_unused int m_can_suspend(struct device *dev) > if (netif_running(ndev)) { > netif_stop_queue(ndev); > netif_device_detach(ndev); > + m_can_stop(ndev); > } > > - /* TODO: enter low power */ > - > priv->can.state = CAN_STATE_SLEEPING; > > return 0; > @@ -1686,11 +1685,23 @@ static __maybe_unused int m_can_resume(struct device *dev) > struct net_device *ndev = dev_get_drvdata(dev); > struct m_can_priv *priv = netdev_priv(ndev); > > - /* TODO: exit low power */ > + m_can_init_ram(priv); > > priv->can.state = CAN_STATE_ERROR_ACTIVE; > > if (netif_running(ndev)) { > + int ret = clk_prepare_enable(priv->hclk); > + > + if (ret) > + return ret; > + > + ret = clk_prepare_enable(priv->cclk); > + if (ret) { > + clk_disable_unprepare(priv->hclk); > + return ret; > + } > + > + m_can_start(ndev); Using m_can_stop() m_can_start() here is the way to go. However, when looking at this hook we se, that the m_can_start/stop functions are not symmetric (as they should be). Either move the clock handling to completely in or out of m_can_start/stop. > netif_device_attach(ndev); > netif_start_queue(ndev); > } > Marc -- Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 3f0445440146..0a06690febe2 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1672,10 +1672,9 @@ static __maybe_unused int m_can_suspend(struct device *dev) if (netif_running(ndev)) { netif_stop_queue(ndev); netif_device_detach(ndev); + m_can_stop(ndev); } - /* TODO: enter low power */ - priv->can.state = CAN_STATE_SLEEPING; return 0; @@ -1686,11 +1685,23 @@ static __maybe_unused int m_can_resume(struct device *dev) struct net_device *ndev = dev_get_drvdata(dev); struct m_can_priv *priv = netdev_priv(ndev); - /* TODO: exit low power */ + m_can_init_ram(priv); priv->can.state = CAN_STATE_ERROR_ACTIVE; if (netif_running(ndev)) { + int ret = clk_prepare_enable(priv->hclk); + + if (ret) + return ret; + + ret = clk_prepare_enable(priv->cclk); + if (ret) { + clk_disable_unprepare(priv->hclk); + return ret; + } + + m_can_start(ndev); netif_device_attach(ndev); netif_start_queue(ndev); }
This adds Power Management deep Suspend/Resume support for Bosch M_CAN chip. When entering deep sleep, the clocks are gated, the interrupts are disabled. When resuming from deep sleep, the chip needs to be reinitialized, the clocks ungated and the interrupts enabled. Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> --- v3: - do not close/reopen the can interface (which was previously done when calling m_can_close), basically do the same routine as in probe but it does not close/open the can device, - update commit log, v2: - fix erroneous commit log, drivers/net/can/m_can/m_can.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) -- 2.11.0