To be more precise, i can't control screen brightness by pressing Fn + Home (increase) or Fn + End (decrease). These are thinkpad's shortcuts for controlling brightness. Controlling brightness by command line works.
The shortcuts worked in OpenBSD 5.9. Dmesg: OpenBSD 6.0 (RAMDISK_CD) #2100: Tue Jul 26 13:05:59 MDT 2016 dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/RAMDISK_CD real mem = 8451125248 (8059MB) avail mem = 8193282048 (7813MB) mainbus0 at root bios0 at mainbus0: SMBIOS rev. 2.6 @ 0xdae9c000 (64 entries) bios0: vendor LENOVO version "8DET70WW (1.40 )" date 05/14/2015 bios0: LENOVO 4291BD2 acpi0 at bios0: rev 2 acpi0: tables DSDT FACP SLIC SSDT SSDT SSDT HPET APIC MCFG ECDT ASF! TCPA SSDT SSDT DMAR UEFI UEFI UEFI acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz, 797.52 MHz cpu0: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,NXE,LONG,LAHF,PERF,ITSC,SENSOR,ARAT cpu0: 256KB 64b/line 8-way L2 cache cpu0: apic clock running at 99MHz cpu0: mwait min=64, max=64, C-substates=0.2.1.1.2, IBE cpu at mainbus0: not configured cpu at mainbus0: not configured cpu at mainbus0: not configured ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 20, 24 pins acpiec0 at acpi0 acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus -1 (PEG_) acpiprt2 at acpi0: bus 2 (EXP1) acpiprt3 at acpi0: bus 3 (EXP2) acpiprt4 at acpi0: bus 5 (EXP4) acpiprt5 at acpi0: bus 13 (EXP5) acpiprt6 at acpi0: bus -1 (EXP7) acpicpu at acpi0 not configured acpipwrres at acpi0 not configured acpitz at acpi0 not configured "PNP0C0D" at acpi0 not configured "PNP0C0E" at acpi0 not configured "PNP0303" at acpi0 not configured "LEN0020" at acpi0 not configured "SMO1200" at acpi0 not configured "PNP0C0A" at acpi0 not configured "ACPI0003" at acpi0 not configured "LEN0068" at acpi0 not configured "PNP0C14" at acpi0 not configured "PNP0C14" at acpi0 not configured pci0 at mainbus0 bus 0 pchb0 at pci0 dev 0 function 0 "Intel Core 2G Host" rev 0x09 vga1 at pci0 dev 2 function 0 "Intel HD Graphics 3000" rev 0x09 wsdisplay1 at vga1 mux 1: console (80x25, vt100 emulation) "Intel 6 Series MEI" rev 0x04 at pci0 dev 22 function 0 not configured em0 at pci0 dev 25 function 0 "Intel 82579LM" rev 0x04: msi, address f0:de:f1:75:23:67 ehci0 at pci0 dev 26 function 0 "Intel 6 Series USB" rev 0x04: apic 2 int 16 usb0 at ehci0: USB revision 2.0 uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1 "Intel 6 Series HD Audio" rev 0x04 at pci0 dev 27 function 0 not configured ppb0 at pci0 dev 28 function 0 "Intel 6 Series PCIE" rev 0xb4: msi pci1 at ppb0 bus 2 ppb1 at pci0 dev 28 function 1 "Intel 6 Series PCIE" rev 0xb4: msi pci2 at ppb1 bus 3 iwn0 at pci2 dev 0 function 0 "Intel Centrino Ultimate-N 6300" rev 0x35: msi, MIMO 3T3R, MoW, address 00:24:d7:59:08:50 ppb2 at pci0 dev 28 function 3 "Intel 6 Series PCIE" rev 0xb4: msi pci3 at ppb2 bus 5 ppb3 at pci0 dev 28 function 4 "Intel 6 Series PCIE" rev 0xb4: msi pci4 at ppb3 bus 13 sdhc0 at pci4 dev 0 function 0 "Ricoh 5U822 SD/MMC" rev 0x07: apic 2 int 16 sdhc0: SDHC 3.0, 50 MHz base clock sdmmc0 at sdhc0: 4-bit, sd high-speed, mmc high-speed, dma ehci1 at pci0 dev 29 function 0 "Intel 6 Series USB" rev 0x04: apic 2 int 23 usb1 at ehci1: USB revision 2.0 uhub1 at usb1 "Intel EHCI root hub" rev 2.00/1.00 addr 1 "Intel QM67 LPC" rev 0x04 at pci0 dev 31 function 0 not configured ahci0 at pci0 dev 31 function 2 "Intel 6 Series AHCI" rev 0x04: msi, AHCI 1.3 ahci0: port 0: 6.0Gb/s scsibus0 at ahci0: 32 targets sd0 at scsibus0 targ 0 lun 0: <ATA, CT250BX100SSD1, MU02> SCSI3 0/direct fixed naa.500a0751f00afc91 sd0: 238475MB, 512 bytes/sector, 488397168 sectors, thin "Intel 6 Series SMBus" rev 0x04 at pci0 dev 31 function 3 not configured isa0 at mainbus0 pckbc0 at isa0 port 0x60/5 irq 1 irq 12 pckbd0 at pckbc0 (kbd slot) wskbd0 at pckbd0: console keyboard, using wsdisplay1 uhub2 at uhub0 port 1 "vendor 0x8087 product 0x0024" rev 2.00/0.00 addr 2 "Broadcom Corp Broadcom Bluetooth Device" rev 2.00/7.48 addr 3 at uhub2 port 4 not configured "Chicony Electronics Co., Ltd. Integrated Camera" rev 2.00/8.54 addr 4 at uhub2 port 6 not configured uhub3 at uhub1 port 1 "vendor 0x8087 product 0x0024" rev 2.00/0.00 addr 2 umass0 at uhub3 port 4 configuration 3 interface 0 "Lenovo F5521gw" rev 2.00/0.00 addr 3 umass0: using SCSI over Bulk-Only scsibus1 at umass0: 2 targets, initiator 0 softraid0 at root scsibus2 at softraid0: 256 targets root on rd0a swap on rd0b dump on rd0b syncing disks... OpenBSD 6.0 (GENERIC.MP) #2319: Tue Jul 26 13:00:43 MDT 2016 dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP real mem = 8451125248 (8059MB) avail mem = 8190525440 (7811MB) mpath0 at root scsibus0 at mpath0: 256 targets mainbus0 at root bios0 at mainbus0: SMBIOS rev. 2.6 @ 0xdae9c000 (64 entries) bios0: vendor LENOVO version "8DET70WW (1.40 )" date 05/14/2015 bios0: LENOVO 4291BD2 acpi0 at bios0: rev 2 acpi0: sleep states S0 S3 S4 S5 acpi0: tables DSDT FACP SLIC SSDT SSDT SSDT HPET APIC MCFG ECDT ASF! TCPA SSDT SSDT DMAR UEFI UEFI UEFI acpi0: wakeup devices LID_(S3) SLPB(S3) IGBE(S4) EXP4(S4) EXP7(S4) EHC1(S3) EHC2(S3) HDEF(S4) acpitimer0 at acpi0: 3579545 Hz, 24 bits acpihpet0 at acpi0: 14318179 Hz acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz, 797.54 MHz cpu0: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,NXE,LONG,LAHF,PERF,ITSC,SENSOR,ARAT cpu0: 256KB 64b/line 8-way L2 cache cpu0: smt 0, core 0, package 0 mtrr: Pentium Pro MTRR support, 10 var ranges, 88 fixed ranges cpu0: apic clock running at 99MHz cpu0: mwait min=64, max=64, C-substates=0.2.1.1.2, IBE cpu1 at mainbus0: apid 1 (application processor) cpu1: Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz, 797.41 MHz cpu1: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,NXE,LONG,LAHF,PERF,ITSC,SENSOR,ARAT cpu1: 256KB 64b/line 8-way L2 cache cpu1: smt 1, core 0, package 0 cpu2 at mainbus0: apid 2 (application processor) cpu2: Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz, 797.41 MHz cpu2: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,NXE,LONG,LAHF,PERF,ITSC,SENSOR,ARAT cpu2: 256KB 64b/line 8-way L2 cache cpu2: smt 0, core 1, package 0 cpu3 at mainbus0: apid 3 (application processor) cpu3: Intel(R) Core(TM) i5-2520M CPU @ 2.50GHz, 797.41 MHz cpu3: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,DEADLINE,AES,XSAVE,AVX,NXE,LONG,LAHF,PERF,ITSC,SENSOR,ARAT cpu3: 256KB 64b/line 8-way L2 cache cpu3: smt 1, core 1, package 0 ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 20, 24 pins acpimcfg0 at acpi0 addr 0xf8000000, bus 0-63 acpiec0 at acpi0 acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus -1 (PEG_) acpiprt2 at acpi0: bus 2 (EXP1) acpiprt3 at acpi0: bus 3 (EXP2) acpiprt4 at acpi0: bus 5 (EXP4) acpiprt5 at acpi0: bus 13 (EXP5) acpiprt6 at acpi0: bus -1 (EXP7) acpicpu0 at acpi0: C3(200@109 io@0x416), C2(500@80 io@0x414), C1(1000@1 halt), PSS acpicpu1 at acpi0: C3(200@109 io@0x416), C2(500@80 io@0x414), C1(1000@1 halt), PSS acpicpu2 at acpi0: C3(200@109 io@0x416), C2(500@80 io@0x414), C1(1000@1 halt), PSS acpicpu3 at acpi0: C3(200@109 io@0x416), C2(500@80 io@0x414), C1(1000@1 halt), PSS acpipwrres0 at acpi0: PUBS, resource for EHC1, EHC2 acpitz0 at acpi0: critical temperature is 99 degC acpibtn0 at acpi0: LID_ acpibtn1 at acpi0: SLPB "PNP0303" at acpi0 not configured "LEN0020" at acpi0 not configured "SMO1200" at acpi0 not configured acpibat0 at acpi0: BAT0 model "42T4865" serial 11681 type LION oem "LGC" acpiac0 at acpi0: AC unit offline acpithinkpad0 at acpi0 "PNP0C14" at acpi0 not configured "PNP0C14" at acpi0 not configured acpidock0 at acpi0: GDCK not docked (0) acpivideo0 at acpi0: VID_ acpivout at acpivideo0 not configured acpivideo1 at acpi0: VID_ cpu0: Enhanced SpeedStep 797 MHz: speeds: 2501, 2500, 2200, 2000, 1800, 1600, 1400, 1200, 1000, 800 MHz pci0 at mainbus0 bus 0 pchb0 at pci0 dev 0 function 0 "Intel Core 2G Host" rev 0x09 inteldrm0 at pci0 dev 2 function 0 "Intel HD Graphics 3000" rev 0x09 drm0 at inteldrm0 inteldrm0: msi inteldrm0: 1366x768 wsdisplay0 at inteldrm0 mux 1: console (std, vt100 emulation) wsdisplay0: screen 1-5 added (std, vt100 emulation) "Intel 6 Series MEI" rev 0x04 at pci0 dev 22 function 0 not configured em0 at pci0 dev 25 function 0 "Intel 82579LM" rev 0x04: msi, address f0:de:f1:75:23:67 ehci0 at pci0 dev 26 function 0 "Intel 6 Series USB" rev 0x04: apic 2 int 16 usb0 at ehci0: USB revision 2.0 uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1 azalia0 at pci0 dev 27 function 0 "Intel 6 Series HD Audio" rev 0x04: msi azalia0: codecs: Conexant CX20590, Intel/0x2805, using Conexant CX20590 audio0 at azalia0 ppb0 at pci0 dev 28 function 0 "Intel 6 Series PCIE" rev 0xb4: msi pci1 at ppb0 bus 2 ppb1 at pci0 dev 28 function 1 "Intel 6 Series PCIE" rev 0xb4: msi pci2 at ppb1 bus 3 iwn0 at pci2 dev 0 function 0 "Intel Centrino Ultimate-N 6300" rev 0x35: msi, MIMO 3T3R, MoW, address 00:24:d7:59:08:50 ppb2 at pci0 dev 28 function 3 "Intel 6 Series PCIE" rev 0xb4: msi pci3 at ppb2 bus 5 ppb3 at pci0 dev 28 function 4 "Intel 6 Series PCIE" rev 0xb4: msi pci4 at ppb3 bus 13 sdhc0 at pci4 dev 0 function 0 "Ricoh 5U822 SD/MMC" rev 0x07: apic 2 int 16 sdhc0: SDHC 3.0, 50 MHz base clock sdmmc0 at sdhc0: 4-bit, sd high-speed, mmc high-speed, dma ehci1 at pci0 dev 29 function 0 "Intel 6 Series USB" rev 0x04: apic 2 int 23 usb1 at ehci1: USB revision 2.0 uhub1 at usb1 "Intel EHCI root hub" rev 2.00/1.00 addr 1 pcib0 at pci0 dev 31 function 0 "Intel QM67 LPC" rev 0x04 ahci0 at pci0 dev 31 function 2 "Intel 6 Series AHCI" rev 0x04: msi, AHCI 1.3 ahci0: port 0: 6.0Gb/s scsibus1 at ahci0: 32 targets sd0 at scsibus1 targ 0 lun 0: <ATA, CT250BX100SSD1, MU02> SCSI3 0/direct fixed naa.500a0751f00afc91 sd0: 238475MB, 512 bytes/sector, 488397168 sectors, thin ichiic0 at pci0 dev 31 function 3 "Intel 6 Series SMBus" rev 0x04: apic 2 int 18 iic0 at ichiic0 spdmem0 at iic0 addr 0x50: 4GB DDR3 SDRAM PC3-12800 SO-DIMM spdmem1 at iic0 addr 0x51: 4GB DDR3 SDRAM PC3-12800 SO-DIMM isa0 at pcib0 isadma0 at isa0 pckbc0 at isa0 port 0x60/5 irq 1 irq 12 pckbd0 at pckbc0 (kbd slot) wskbd0 at pckbd0: console keyboard, using wsdisplay0 pms0 at pckbc0 (aux slot) wsmouse0 at pms0 mux 0 wsmouse1 at pms0 mux 0 pms0: Synaptics clickpad, firmware 8.0 pcppi0 at isa0 port 0x61 spkr0 at pcppi0 aps0 at isa0 port 0x1600/31 uhub2 at uhub0 port 1 "Intel Rate Matching Hub" rev 2.00/0.00 addr 2 ugen0 at uhub2 port 4 "Broadcom Corp Broadcom Bluetooth Device" rev 2.00/7.48 addr 3 uvideo0 at uhub2 port 6 configuration 1 interface 0 "Chicony Electronics Co., Ltd. Integrated Camera" rev 2.00/8.54 addr 4 video0 at uvideo0 uhub3 at uhub1 port 1 "Intel Rate Matching Hub" rev 2.00/0.00 addr 2 umodem0 at uhub3 port 4 configuration 1 interface 1 "Lenovo F5521gw" rev 2.00/0.00 addr 3 umodem0: data interface 2, has CM over data, has break umodem0: status change notification available ucom0 at umodem0 umodem1 at uhub3 port 4 configuration 1 interface 3 "Lenovo F5521gw" rev 2.00/0.00 addr 3 umodem1: data interface 4, has CM over data, has break umodem1: status change notification available ucom1 at umodem1 umodem2 at uhub3 port 4 configuration 1 interface 9 "Lenovo F5521gw" rev 2.00/0.00 addr 3 umodem2: data interface 10, has CM over data, has break umodem2: status change notification available ucom2 at umodem2 ugen1 at uhub3 port 4 configuration 1 "Lenovo F5521gw" rev 2.00/0.00 addr 3 vscsi0 at root scsibus2 at vscsi0: 256 targets softraid0 at root scsibus3 at softraid0: 256 targets root on sd0a (3f443d551ed1bc71.a) swap on sd0b dump on sd0b hw.sensors.cpu0.temp0=46.00 degC hw.sensors.acpitz0.temp0=44.00 degC (zone temperature) hw.sensors.acpibtn0.indicator0=On (lid open) hw.sensors.acpibat0.volt0=11.10 VDC (voltage) hw.sensors.acpibat0.volt1=11.66 VDC (current voltage) hw.sensors.acpibat0.power0=12.32 W (rate) hw.sensors.acpibat0.watthour0=48.89 Wh (last full capacity) hw.sensors.acpibat0.watthour1=2.44 Wh (warning capacity) hw.sensors.acpibat0.watthour2=0.20 Wh (low capacity) hw.sensors.acpibat0.watthour3=38.68 Wh (remaining capacity), OK hw.sensors.acpibat0.watthour4=57.72 Wh (design capacity) hw.sensors.acpibat0.raw0=1 (battery discharging), OK hw.sensors.acpiac0.indicator0=Off (power supply) hw.sensors.acpithinkpad0.temp0=44.00 degC hw.sensors.acpithinkpad0.temp1=44.00 degC hw.sensors.acpithinkpad0.temp2=44.00 degC hw.sensors.acpithinkpad0.temp3=44.00 degC hw.sensors.acpithinkpad0.temp4=44.00 degC hw.sensors.acpithinkpad0.temp5=44.00 degC hw.sensors.acpithinkpad0.temp6=44.00 degC hw.sensors.acpithinkpad0.temp7=44.00 degC hw.sensors.acpithinkpad0.fan0=1966 RPM hw.sensors.acpidock0.indicator0=Off (not docked), UNKNOWN hw.sensors.aps0.temp0=40.00 degC hw.sensors.aps0.temp1=40.00 degC hw.sensors.aps0.indicator0=Off (Keyboard Active) hw.sensors.aps0.indicator1=Off (Mouse Active) hw.sensors.aps0.indicator2=On (Lid Open) hw.sensors.aps0.raw0=511 (X_ACCEL) hw.sensors.aps0.raw1=506 (Y_ACCEL) hw.sensors.aps0.raw2=511 (X_VAR) hw.sensors.aps0.raw3=506 (Y_VAR)