| Message ID | 20231117094425.80477-5-ilpo.jarvinen@linux.intel.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | rtlwifi: PCIe capability access fix + improvements | expand |
On Fri, Nov 17, 2023 at 11:44:22AM +0200, Ilpo Järvinen wrote: > Check if PM capability does not exists and return early which follows > the usual error handling pattern. > > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> > --- > .../wireless/realtek/rtlwifi/rtl8821ae/hw.c | 45 ++++++++++--------- > 1 file changed, 23 insertions(+), 22 deletions(-) > > diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c > index 6ae37d61a2a2..53cfeed0b030 100644 > --- a/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c > +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c > @@ -2305,30 +2305,31 @@ static void _rtl8821ae_clear_pci_pme_status(struct ieee80211_hw *hw) > } > } while (cnt++ < 200); > > - if (cap_id == 0x01) { > - /* Get the PM CSR (Control/Status Register), > - * The PME_Status is located at PM Capatibility offset 5, bit 7 > - */ > - pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, &pmcs_reg); > - > - if (pmcs_reg & BIT(7)) { > - /* Clear PME_Status with write */ > - pci_write_config_byte(rtlpci->pdev, cap_pointer + 5, > - pmcs_reg); > - /* Read it back to check */ > - pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, > - &pmcs_reg); > - rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, > - "Clear PME status 0x%2x to 0x%2x\n", > - cap_pointer + 5, pmcs_reg); > - } else { > - rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, > - "PME status(0x%2x) = 0x%2x\n", > - cap_pointer + 5, pmcs_reg); > - } > - } else { > + if (cap_id != 0x01) { > rtl_dbg(rtlpriv, COMP_INIT, DBG_WARNING, > "Cannot find PME Capability\n"); > + return; > + } > + > + /* Get the PM CSR (Control/Status Register), > + * The PME_Status is located at PM Capatibility offset 5, bit 7 s/Capatibility/Capability/ But this is PCI_PM_CTRL and PCI_PM_CTRL_PME_STATUS (with a word read), right? No need for a comment then. I don't know why the driver needs to do this, but I'm skeptical. The only other drivers that look at PCI_PM_CTRL_PME_STATUS themselves are bnx2x and ksz884xp (ksz884x.c), so this is highly suspicious. > + */ > + pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, &pmcs_reg); > + > + if (pmcs_reg & BIT(7)) { > + /* Clear PME_Status with write */ > + pci_write_config_byte(rtlpci->pdev, cap_pointer + 5, > + pmcs_reg); > + /* Read it back to check */ > + pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, > + &pmcs_reg); > + rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, > + "Clear PME status 0x%2x to 0x%2x\n", > + cap_pointer + 5, pmcs_reg); > + } else { > + rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, > + "PME status(0x%2x) = 0x%2x\n", > + cap_pointer + 5, pmcs_reg); > } > } > > -- > 2.30.2 >
On Fri, 17 Nov 2023, Bjorn Helgaas wrote: > On Fri, Nov 17, 2023 at 11:44:22AM +0200, Ilpo Järvinen wrote: > > Check if PM capability does not exists and return early which follows > > the usual error handling pattern. > > > > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> > > --- > > .../wireless/realtek/rtlwifi/rtl8821ae/hw.c | 45 ++++++++++--------- > > 1 file changed, 23 insertions(+), 22 deletions(-) > > > > diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c > > index 6ae37d61a2a2..53cfeed0b030 100644 > > --- a/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c > > +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c > > @@ -2305,30 +2305,31 @@ static void _rtl8821ae_clear_pci_pme_status(struct ieee80211_hw *hw) > > } > > } while (cnt++ < 200); > > > > - if (cap_id == 0x01) { > > - /* Get the PM CSR (Control/Status Register), > > - * The PME_Status is located at PM Capatibility offset 5, bit 7 > > - */ > > - pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, &pmcs_reg); > > - > > - if (pmcs_reg & BIT(7)) { > > - /* Clear PME_Status with write */ > > - pci_write_config_byte(rtlpci->pdev, cap_pointer + 5, > > - pmcs_reg); > > - /* Read it back to check */ > > - pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, > > - &pmcs_reg); > > - rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, > > - "Clear PME status 0x%2x to 0x%2x\n", > > - cap_pointer + 5, pmcs_reg); > > - } else { > > - rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, > > - "PME status(0x%2x) = 0x%2x\n", > > - cap_pointer + 5, pmcs_reg); > > - } > > - } else { > > + if (cap_id != 0x01) { > > rtl_dbg(rtlpriv, COMP_INIT, DBG_WARNING, > > "Cannot find PME Capability\n"); > > + return; > > + } > > + > > + /* Get the PM CSR (Control/Status Register), > > + * The PME_Status is located at PM Capatibility offset 5, bit 7 > But this is PCI_PM_CTRL and PCI_PM_CTRL_PME_STATUS (with a word read), > right? No need for a comment then. > > I don't know why the driver needs to do this, but I'm skeptical. The > only other drivers that look at PCI_PM_CTRL_PME_STATUS themselves are > bnx2x and ksz884xp (ksz884x.c), so this is highly suspicious. I hope you are not asking from me because I'm just the poor guy who tries to cleanup this mess. ;-) ...So all I can do is shrug and say, I unfortunately don't know the answer. Hopefully somebody more familiar with the devices could chime in.
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c index 6ae37d61a2a2..53cfeed0b030 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8821ae/hw.c @@ -2305,30 +2305,31 @@ static void _rtl8821ae_clear_pci_pme_status(struct ieee80211_hw *hw) } } while (cnt++ < 200); - if (cap_id == 0x01) { - /* Get the PM CSR (Control/Status Register), - * The PME_Status is located at PM Capatibility offset 5, bit 7 - */ - pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, &pmcs_reg); - - if (pmcs_reg & BIT(7)) { - /* Clear PME_Status with write */ - pci_write_config_byte(rtlpci->pdev, cap_pointer + 5, - pmcs_reg); - /* Read it back to check */ - pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, - &pmcs_reg); - rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, - "Clear PME status 0x%2x to 0x%2x\n", - cap_pointer + 5, pmcs_reg); - } else { - rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, - "PME status(0x%2x) = 0x%2x\n", - cap_pointer + 5, pmcs_reg); - } - } else { + if (cap_id != 0x01) { rtl_dbg(rtlpriv, COMP_INIT, DBG_WARNING, "Cannot find PME Capability\n"); + return; + } + + /* Get the PM CSR (Control/Status Register), + * The PME_Status is located at PM Capatibility offset 5, bit 7 + */ + pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, &pmcs_reg); + + if (pmcs_reg & BIT(7)) { + /* Clear PME_Status with write */ + pci_write_config_byte(rtlpci->pdev, cap_pointer + 5, + pmcs_reg); + /* Read it back to check */ + pci_read_config_byte(rtlpci->pdev, cap_pointer + 5, + &pmcs_reg); + rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, + "Clear PME status 0x%2x to 0x%2x\n", + cap_pointer + 5, pmcs_reg); + } else { + rtl_dbg(rtlpriv, COMP_INIT, DBG_DMESG, + "PME status(0x%2x) = 0x%2x\n", + cap_pointer + 5, pmcs_reg); } }
Check if PM capability does not exists and return early which follows the usual error handling pattern. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> --- .../wireless/realtek/rtlwifi/rtl8821ae/hw.c | 45 ++++++++++--------- 1 file changed, 23 insertions(+), 22 deletions(-)