| Message ID | 20211110221456.11977-2-jim2101024@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: brcmstb: have portdrv turn on sub-device power | expand |
On Wed, Nov 10, 2021 at 05:14:41PM -0500, Jim Quinlan wrote: > We do not use the result of this function so make it void. I don't get it. Can you expand on this? brcm_phy_cntl() can return -EIO, which means brcm_phy_stop() can return -EIO, which means brcm_pcie_suspend can return -EIO. brcm_pcie_suspend() is the dev_pm_ops.suspend() method. So are you saying we never use the result of dev_pm_ops.suspend()? > Signed-off-by: Jim Quinlan <jim2101024@gmail.com> > --- > drivers/pci/controller/pcie-brcmstb.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c > index cc30215f5a43..ff7d0d291531 100644 > --- a/drivers/pci/controller/pcie-brcmstb.c > +++ b/drivers/pci/controller/pcie-brcmstb.c > @@ -1111,9 +1111,10 @@ static inline int brcm_phy_start(struct brcm_pcie *pcie) > return pcie->rescal ? brcm_phy_cntl(pcie, 1) : 0; > } > > -static inline int brcm_phy_stop(struct brcm_pcie *pcie) > +static inline void brcm_phy_stop(struct brcm_pcie *pcie) > { > - return pcie->rescal ? brcm_phy_cntl(pcie, 0) : 0; > + if (pcie->rescal) > + brcm_phy_cntl(pcie, 0); > } > > static void brcm_pcie_turn_off(struct brcm_pcie *pcie) > @@ -1143,14 +1144,13 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie) > static int brcm_pcie_suspend(struct device *dev) > { > struct brcm_pcie *pcie = dev_get_drvdata(dev); > - int ret; > > brcm_pcie_turn_off(pcie); > - ret = brcm_phy_stop(pcie); > + brcm_phy_stop(pcie); > reset_control_rearm(pcie->rescal); > clk_disable_unprepare(pcie->clk); > > - return ret; > + return 0; > } > > static int brcm_pcie_resume(struct device *dev) > -- > 2.17.1 >
On Thu, Nov 11, 2021 at 4:57 PM Bjorn Helgaas <helgaas@kernel.org> wrote: > > On Wed, Nov 10, 2021 at 05:14:41PM -0500, Jim Quinlan wrote: > > We do not use the result of this function so make it void. > > I don't get it. Can you expand on this? > > brcm_phy_cntl() can return -EIO, which means brcm_phy_stop() can > return -EIO, which means brcm_pcie_suspend can return -EIO. > brcm_pcie_suspend() is the dev_pm_ops.suspend() method. > > So are you saying we never use the result of dev_pm_ops.suspend()? Hi Bjorn, In this situation we are going into suspend. In doing so, any problems with the brcm phy may be erased/forgiven upon resume, since clocks are turned off and most power removed/reduced. An error from brcm_phy_stop() that becomes the return value of brcm_pcie_suspend() will bring a halt to the entire suspend IIRC. In fact, I forced a -EIO in this code and it panic'd on suspend. This is not really the behavior I want for what is most likely a recoverable error. Perhaps a dev_err(...) will suffice while still returning 0? I noticed that reset_control_rearm() also returns a value, and if that is in error it will not be erease/forgiven by suspend sleep. I will fix this. Regards, Jim Quinlan Broadcom STB > > > Signed-off-by: Jim Quinlan <jim2101024@gmail.com> > > --- > > drivers/pci/controller/pcie-brcmstb.c | 10 +++++----- > > 1 file changed, 5 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c > > index cc30215f5a43..ff7d0d291531 100644 > > --- a/drivers/pci/controller/pcie-brcmstb.c > > +++ b/drivers/pci/controller/pcie-brcmstb.c > > @@ -1111,9 +1111,10 @@ static inline int brcm_phy_start(struct brcm_pcie *pcie) > > return pcie->rescal ? brcm_phy_cntl(pcie, 1) : 0; > > } > > > > -static inline int brcm_phy_stop(struct brcm_pcie *pcie) > > +static inline void brcm_phy_stop(struct brcm_pcie *pcie) > > { > > - return pcie->rescal ? brcm_phy_cntl(pcie, 0) : 0; > > + if (pcie->rescal) > > + brcm_phy_cntl(pcie, 0); > > } > > > > static void brcm_pcie_turn_off(struct brcm_pcie *pcie) > > @@ -1143,14 +1144,13 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie) > > static int brcm_pcie_suspend(struct device *dev) > > { > > struct brcm_pcie *pcie = dev_get_drvdata(dev); > > - int ret; > > > > brcm_pcie_turn_off(pcie); > > - ret = brcm_phy_stop(pcie); > > + brcm_phy_stop(pcie); > > reset_control_rearm(pcie->rescal); > > clk_disable_unprepare(pcie->clk); > > > > - return ret; > > + return 0; > > } > > > > static int brcm_pcie_resume(struct device *dev) > > -- > > 2.17.1 > >
On Mon, Nov 15, 2021 at 03:56:14PM -0500, Jim Quinlan wrote: > On Thu, Nov 11, 2021 at 4:57 PM Bjorn Helgaas <helgaas@kernel.org> wrote: > > On Wed, Nov 10, 2021 at 05:14:41PM -0500, Jim Quinlan wrote: > > > We do not use the result of this function so make it void. > > > > I don't get it. Can you expand on this? > > > > brcm_phy_cntl() can return -EIO, which means brcm_phy_stop() can > > return -EIO, which means brcm_pcie_suspend can return -EIO. > > brcm_pcie_suspend() is the dev_pm_ops.suspend() method. > > > > So are you saying we never use the result of dev_pm_ops.suspend()? > > In this situation we are going into suspend. In doing so, any > problems with the brcm phy may be erased/forgiven upon resume, since > clocks are turned off and most power removed/reduced. An error from > brcm_phy_stop() that becomes the return value of brcm_pcie_suspend() > will bring a halt to the entire suspend IIRC. In fact, I forced a > -EIO in this code and it panic'd on suspend. This is not really the > behavior I want for what is most likely a recoverable error. > > Perhaps a dev_err(...) will suffice while still returning 0? Maybe we just need a note about why we want to intentionally ignore any errors here. > I noticed that reset_control_rearm() also returns a value, and if that > is in error it will not be erease/forgiven by suspend sleep. I will > fix this. > > Regards, > Jim Quinlan > Broadcom STB > > > > > > > Signed-off-by: Jim Quinlan <jim2101024@gmail.com> > > > --- > > > drivers/pci/controller/pcie-brcmstb.c | 10 +++++----- > > > 1 file changed, 5 insertions(+), 5 deletions(-) > > > > > > diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c > > > index cc30215f5a43..ff7d0d291531 100644 > > > --- a/drivers/pci/controller/pcie-brcmstb.c > > > +++ b/drivers/pci/controller/pcie-brcmstb.c > > > @@ -1111,9 +1111,10 @@ static inline int brcm_phy_start(struct brcm_pcie *pcie) > > > return pcie->rescal ? brcm_phy_cntl(pcie, 1) : 0; > > > } > > > > > > -static inline int brcm_phy_stop(struct brcm_pcie *pcie) > > > +static inline void brcm_phy_stop(struct brcm_pcie *pcie) > > > { > > > - return pcie->rescal ? brcm_phy_cntl(pcie, 0) : 0; > > > + if (pcie->rescal) > > > + brcm_phy_cntl(pcie, 0); > > > } > > > > > > static void brcm_pcie_turn_off(struct brcm_pcie *pcie) > > > @@ -1143,14 +1144,13 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie) > > > static int brcm_pcie_suspend(struct device *dev) > > > { > > > struct brcm_pcie *pcie = dev_get_drvdata(dev); > > > - int ret; > > > > > > brcm_pcie_turn_off(pcie); > > > - ret = brcm_phy_stop(pcie); > > > + brcm_phy_stop(pcie); > > > reset_control_rearm(pcie->rescal); > > > clk_disable_unprepare(pcie->clk); > > > > > > - return ret; > > > + return 0; > > > } > > > > > > static int brcm_pcie_resume(struct device *dev) > > > -- > > > 2.17.1 > > >
diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index cc30215f5a43..ff7d0d291531 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -1111,9 +1111,10 @@ static inline int brcm_phy_start(struct brcm_pcie *pcie) return pcie->rescal ? brcm_phy_cntl(pcie, 1) : 0; } -static inline int brcm_phy_stop(struct brcm_pcie *pcie) +static inline void brcm_phy_stop(struct brcm_pcie *pcie) { - return pcie->rescal ? brcm_phy_cntl(pcie, 0) : 0; + if (pcie->rescal) + brcm_phy_cntl(pcie, 0); } static void brcm_pcie_turn_off(struct brcm_pcie *pcie) @@ -1143,14 +1144,13 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie) static int brcm_pcie_suspend(struct device *dev) { struct brcm_pcie *pcie = dev_get_drvdata(dev); - int ret; brcm_pcie_turn_off(pcie); - ret = brcm_phy_stop(pcie); + brcm_phy_stop(pcie); reset_control_rearm(pcie->rescal); clk_disable_unprepare(pcie->clk); - return ret; + return 0; } static int brcm_pcie_resume(struct device *dev)
We do not use the result of this function so make it void. Signed-off-by: Jim Quinlan <jim2101024@gmail.com> --- drivers/pci/controller/pcie-brcmstb.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)