diff --git a/arch/x86/include/asm/iosf_mbi.h b/arch/x86/include/asm/iosf_mbi.h index f6119d0e8cba..c313cac36f56 100644 --- a/arch/x86/include/asm/iosf_mbi.h +++ b/arch/x86/include/asm/iosf_mbi.h @@ -5,6 +5,8 @@ #ifndef IOSF_MBI_SYMS_H #define IOSF_MBI_SYMS_H +#include + #define MBI_MCR_OFFSET 0xD0 #define MBI_MDR_OFFSET 0xD4 #define MBI_MCRX_OFFSET 0xD8 @@ -47,6 +49,10 @@ #define QRK_MBI_UNIT_MM 0x05 #define QRK_MBI_UNIT_SOC 0x31 +/* Action values for the pmic_bus_access_notifier functions */ +#define MBI_PMIC_BUS_ACCESS_BEGIN 1 +#define MBI_PMIC_BUS_ACCESS_END 2 + #if IS_ENABLED(CONFIG_IOSF_MBI) bool iosf_mbi_available(void); @@ -115,6 +121,38 @@ void iosf_mbi_punit_acquire(void); */ void iosf_mbi_punit_release(void); +/** + * iosf_mbi_register_pmic_bus_access_notifier - Register PMIC bus notifier + * + * This function can be used by drivers which may need to acquire P-Unit + * managed resources from interrupt context, where iosf_mbi_punit_acquire() + * can not be used. + * + * This function allows a driver to register a notifier to get notified (in a + * process context) before other drivers start accessing the PMIC bus. + * + * This allows the driver to acquire any resources, which it may need during + * the window the other driver is accessing the PMIC, before hand. + * + * @nb: notifier_block to register + */ +int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb); + +/** + * iosf_mbi_register_pmic_bus_access_notifier - Unregister PMIC bus notifier + * + * @nb: notifier_block to unregister + */ +int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb); + +/** + * iosf_mbi_call_pmic_bus_access_notifier_chain - Call PMIC bus notifier chain + * + * @val: action to pass into listener's notifier_call function + * @v: data pointer to pass into listener's notifier_call function + */ +int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v); + #else /* CONFIG_IOSF_MBI is not enabled */ static inline bool iosf_mbi_available(void) @@ -146,6 +184,24 @@ int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask) static inline void iosf_mbi_punit_acquire(void) {} static inline void iosf_mbi_punit_release(void) {} +static inline +int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb) +{ + return 0; +} + +static inline +int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb) +{ + return 0; +} + +static inline +int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v) +{ + return 0; +} + #endif /* CONFIG_IOSF_MBI */ #endif /* IOSF_MBI_SYMS_H */ diff --git a/arch/x86/platform/intel/iosf_mbi.c b/arch/x86/platform/intel/iosf_mbi.c index ed24fa9fb65d..a952ac199741 100644 --- a/arch/x86/platform/intel/iosf_mbi.c +++ b/arch/x86/platform/intel/iosf_mbi.c @@ -35,6 +35,7 @@ static struct pci_dev *mbi_pdev; static DEFINE_SPINLOCK(iosf_mbi_lock); static DEFINE_MUTEX(iosf_mbi_punit_mutex); +static BLOCKING_NOTIFIER_HEAD(iosf_mbi_pmic_bus_access_notifier); static inline u32 iosf_mbi_form_mcr(u8 op, u8 port, u8 offset) { @@ -203,6 +204,41 @@ void iosf_mbi_punit_release(void) } EXPORT_SYMBOL(iosf_mbi_punit_release); +int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb) +{ + int ret; + + /* Wait for the bus to go inactive before registering */ + mutex_lock(&iosf_mbi_punit_mutex); + ret = blocking_notifier_chain_register( + &iosf_mbi_pmic_bus_access_notifier, nb); + mutex_unlock(&iosf_mbi_punit_mutex); + + return ret; +} +EXPORT_SYMBOL(iosf_mbi_register_pmic_bus_access_notifier); + +int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb) +{ + int ret; + + /* Wait for the bus to go inactive before unregistering */ + mutex_lock(&iosf_mbi_punit_mutex); + ret = blocking_notifier_chain_unregister( + &iosf_mbi_pmic_bus_access_notifier, nb); + mutex_unlock(&iosf_mbi_punit_mutex); + + return ret; +} +EXPORT_SYMBOL(iosf_mbi_unregister_pmic_bus_access_notifier); + +int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v) +{ + return blocking_notifier_call_chain( + &iosf_mbi_pmic_bus_access_notifier, val, v); +} +EXPORT_SYMBOL(iosf_mbi_call_pmic_bus_access_notifier_chain); + #ifdef CONFIG_IOSF_MBI_DEBUG static u32 dbg_mdr; static u32 dbg_mcr;