From e8a6123e9ead1b0d40349809e51de9341312fe08 Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Sun, 23 Oct 2016 13:55:34 +0200 Subject: x86/platform/intel-mid: Retrofit pci_platform_pm_ops ->get_state hook Commit cc7cc02bada8 ("PCI: Query platform firmware for device power state") augmented struct pci_platform_pm_ops with a ->get_state hook and implemented it for acpi_pci_platform_pm, the only pci_platform_pm_ops existing till v4.7. However v4.8 introduced another pci_platform_pm_ops for Intel Mobile Internet Devices with commit 5823d0893ec2 ("x86/platform/intel-mid: Add Power Management Unit driver"). It is missing the ->get_state hook, which is fatal since pci_set_platform_pm() enforces its presence. Andy Shevchenko reports that without the present commit, such a device "crashes without even a character printed out on serial console and reboots (since watchdog)". Retrofit mid_pci_platform_pm with the missing callback to fix the breakage. Acked-and-tested-by: Andy Shevchenko Fixes: cc7cc02bada8 ("PCI: Query platform firmware for device power state") Signed-off-by: Lukas Wunner Acked-by: Bjorn Helgaas Cc: linux-pci@vger.kernel.org Cc: Andy Shevchenko Link: http://lkml.kernel.org/r/7c1567d4c49303a4aada94ba16275cbf56b8976b.1477221514.git.lukas@wunner.de Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/intel-mid.h | 1 + arch/x86/platform/intel-mid/pwr.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/intel-mid.h b/arch/x86/include/asm/intel-mid.h index 5b6753d1f7f4..49da9f497b90 100644 --- a/arch/x86/include/asm/intel-mid.h +++ b/arch/x86/include/asm/intel-mid.h @@ -17,6 +17,7 @@ extern int intel_mid_pci_init(void); extern int intel_mid_pci_set_power_state(struct pci_dev *pdev, pci_power_t state); +extern pci_power_t intel_mid_pci_get_power_state(struct pci_dev *pdev); extern void intel_mid_pwr_power_off(void); diff --git a/arch/x86/platform/intel-mid/pwr.c b/arch/x86/platform/intel-mid/pwr.c index 5d3b45ad1c03..67375dda451c 100644 --- a/arch/x86/platform/intel-mid/pwr.c +++ b/arch/x86/platform/intel-mid/pwr.c @@ -272,6 +272,25 @@ int intel_mid_pci_set_power_state(struct pci_dev *pdev, pci_power_t state) } EXPORT_SYMBOL_GPL(intel_mid_pci_set_power_state); +pci_power_t intel_mid_pci_get_power_state(struct pci_dev *pdev) +{ + struct mid_pwr *pwr = midpwr; + int id, reg, bit; + u32 power; + + if (!pwr || !pwr->available) + return PCI_UNKNOWN; + + id = intel_mid_pwr_get_lss_id(pdev); + if (id < 0) + return PCI_UNKNOWN; + + reg = (id * LSS_PWS_BITS) / 32; + bit = (id * LSS_PWS_BITS) % 32; + power = mid_pwr_get_state(pwr, reg); + return (__force pci_power_t)((power >> bit) & 3); +} + void intel_mid_pwr_power_off(void) { struct mid_pwr *pwr = midpwr; -- cgit v1.2.3