/* * Backlight Driver for HP Jornada 680 * * Copyright (c) 2005 Andriy Skulysh * * Based on Sharp's Corgi Backlight Driver * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. */ #include #include #include #include #include #include #include #include #include #include #define HP680_MAX_INTENSITY 255 #define HP680_DEFAULT_INTENSITY 10 static int hp680bl_suspended; static int current_intensity; static DEFINE_SPINLOCK(bl_lock); static void hp680bl_send_intensity(struct backlight_device *bd) { unsigned long flags; u16 v; int intensity = bd->props.brightness; if (bd->props.power != FB_BLANK_UNBLANK) intensity = 0; if (bd->props.fb_blank != FB_BLANK_UNBLANK) intensity = 0; if (hp680bl_suspended) intensity = 0; spin_lock_irqsave(&bl_lock, flags); if (intensity && current_intensity == 0) { sh_dac_enable(DAC_LCD_BRIGHTNESS); v = inw(HD64461_GPBDR); v &= ~HD64461_GPBDR_LCDOFF; outw(v, HD64461_GPBDR); sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); } else if (intensity == 0 && current_intensity != 0) { sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); sh_dac_disable(DAC_LCD_BRIGHTNESS); v = inw(HD64461_GPBDR); v |= HD64461_GPBDR_LCDOFF; outw(v, HD64461_GPBDR); } else if (intensity) { sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); } spin_unlock_irqrestore(&bl_lock, flags); current_intensity = intensity; } #ifdef CONFIG_PM_SLEEP static int hp680bl_suspend(struct device *dev) { struct backlight_device *bd = dev_get_drvdata(dev); hp680bl_suspended = 1; hp680bl_send_intensity(bd); return 0; } static int hp680bl_resume(struct device *dev) { struct backlight_device *bd = dev_get_drvdata(dev); hp680bl_suspended = 0; hp680bl_send_intensity(bd); return 0; } #endif static SIMPLE_DEV_PM_OPS(hp680bl_pm_ops, hp680bl_suspend, hp680bl_resume); static int hp680bl_set_intensity(struct backlight_device *bd) { hp680bl_send_intensity(bd); return 0; } static int hp680bl_get_intensity(struct backlight_device *bd) { return current_intensity; } static const struct backlight_ops hp680bl_ops = { .get_brightness = hp680bl_get_intensity, .update_status = hp680bl_set_intensity, }; static int hp680bl_probe(struct platform_device *pdev) { struct backlight_properties props; struct backlight_device *bd; memset(&props, 0, sizeof(struct backlight_properties)); props.type = BACKLIGHT_RAW; props.max_brightness = HP680_MAX_INTENSITY; bd = devm_backlight_device_register(&pdev->dev, "hp680-bl", &pdev->dev, NULL, &hp680bl_ops, &props); if (IS_ERR(bd)) return PTR_ERR(bd); platform_set_drvdata(pdev, bd); bd->props.brightness = HP680_DEFAULT_INTENSITY; hp680bl_send_intensity(bd); return 0; } static int hp680bl_remove(struct platform_device *pdev) { struct backlight_device *bd = platform_get_drvdata(pdev); bd->props.brightness = 0; bd->props.power = 0; hp680bl_send_intensity(bd); return 0; } static struct platform_driver hp680bl_driver = { .probe = hp680bl_probe, .remove = hp680bl_remove, .driver = { .name = "hp680-bl", .pm = &hp680bl_pm_ops, }, }; static struct platform_device *hp680bl_device; static int __init hp680bl_init(void) { int ret; ret = platform_driver_register(&hp680bl_driver); if (ret) return ret; hp680bl_device = platform_device_register_simple("hp680-bl", -1, NULL, 0); if (IS_ERR(hp680bl_device)) { platform_driver_unregister(&hp680bl_driver); return PTR_ERR(hp680bl_device); } return 0; } static void __exit hp680bl_exit(void) { platform_device_unregister(hp680bl_device); platform_driver_unregister(&hp680bl_driver); } module_init(hp680bl_init); module_exit(hp680bl_exit); MODULE_AUTHOR("Andriy Skulysh "); MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver"); MODULE_LICENSE("GPL"); space:mode:
authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-02-01 17:45:02 +0000
committerIngo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100
commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch)
treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /drivers/usb/host/sl811.h
parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/usb/host/sl811.h')