On failure pcie_capability_read_word() sets it's last parameter, val to 0. In which case (val & PCI_EXP_DEVCTL2_LTR_EN) evaluates to 0. However, with Patch 12/12, it is possible that val is set to ~0 on failure. This would introduce a bug because (x & x) == (~0 & x). Since ~0 is an invalid value here, Add an extra check for ~0 to the if condition to ensure success. Suggested-by: Bjorn Helgaas <bjorn@xxxxxxxxxxx> Signed-off-by: Saheed O. Bolarinwa <refactormyself@xxxxxxxxx> --- drivers/misc/cardreader/rts5227.c | 2 +- drivers/misc/cardreader/rts5249.c | 2 +- drivers/misc/cardreader/rts5260.c | 2 +- drivers/misc/cardreader/rts5261.c | 2 +- 4 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/misc/cardreader/rts5227.c b/drivers/misc/cardreader/rts5227.c index 3a9467aaa435..cab816639df1 100644 --- a/drivers/misc/cardreader/rts5227.c +++ b/drivers/misc/cardreader/rts5227.c @@ -106,7 +106,7 @@ static int rts5227_extra_init_hw(struct rtsx_pcr *pcr) rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, OLT_LED_CTL, 0x0F, 0x02); /* Configure LTR */ pcie_capability_read_word(pcr->pci, PCI_EXP_DEVCTL2, &cap); - if (cap & PCI_EXP_DEVCTL2_LTR_EN) + if ((cap != (u16)~0) && (cap & PCI_EXP_DEVCTL2_LTR_EN)) rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, LTR_CTL, 0xFF, 0xA3); /* Configure OBFF */ rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, OBFF_CFG, 0x03, 0x03); diff --git a/drivers/misc/cardreader/rts5249.c b/drivers/misc/cardreader/rts5249.c index 6c6c9e95a29f..4382ac753fda 100644 --- a/drivers/misc/cardreader/rts5249.c +++ b/drivers/misc/cardreader/rts5249.c @@ -119,7 +119,7 @@ static void rts5249_init_from_cfg(struct rtsx_pcr *pcr) u16 val; pcie_capability_read_word(pcr->pci, PCI_EXP_DEVCTL2, &val); - if (val & PCI_EXP_DEVCTL2_LTR_EN) { + if ((val != (u16)~0) && (val & PCI_EXP_DEVCTL2_LTR_EN)) { option->ltr_enabled = true; option->ltr_active = true; rtsx_set_ltr_latency(pcr, option->ltr_active_latency); diff --git a/drivers/misc/cardreader/rts5260.c b/drivers/misc/cardreader/rts5260.c index 7a9dbb778e84..3d52c86aaaa3 100644 --- a/drivers/misc/cardreader/rts5260.c +++ b/drivers/misc/cardreader/rts5260.c @@ -519,7 +519,7 @@ static void rts5260_init_from_cfg(struct rtsx_pcr *pcr) u16 val; pcie_capability_read_word(pcr->pci, PCI_EXP_DEVCTL2, &val); - if (val & PCI_EXP_DEVCTL2_LTR_EN) { + if ((val != (u16)~0) && (val & PCI_EXP_DEVCTL2_LTR_EN)) { option->ltr_enabled = true; option->ltr_active = true; rtsx_set_ltr_latency(pcr, option->ltr_active_latency); diff --git a/drivers/misc/cardreader/rts5261.c b/drivers/misc/cardreader/rts5261.c index 195822ec858e..7e1188740194 100644 --- a/drivers/misc/cardreader/rts5261.c +++ b/drivers/misc/cardreader/rts5261.c @@ -440,7 +440,7 @@ static void rts5261_init_from_cfg(struct rtsx_pcr *pcr) u16 val; pcie_capability_read_word(pcr->pci, PCI_EXP_DEVCTL2, &val); - if (val & PCI_EXP_DEVCTL2_LTR_EN) { + if ((val != (u16)~0) && (val & PCI_EXP_DEVCTL2_LTR_EN)) { option->ltr_enabled = true; option->ltr_active = true; rtsx_set_ltr_latency(pcr, option->ltr_active_latency); -- 2.18.4