On Tuesday, April 08, 2014 12:06:55 AM Zhang Rui wrote: > When the lpss scan handler is compiled out, aka, CONFIG_X86_INTEL_LPSS > is cleared, those ACPI device objects will be recgonized as regular > _HID devices, and a platform device would be created for each of them. > This is wrong because the platform drivers for those devices would > be loaded, but with broken behavior. > > In order to fix this, a dummy lpss scan handler is introduced > to prevent those platform devices from being created. > Plus, if lpt_clk_init() fails, we need this dummy scan handler as well. > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> All of the patches adding dummy scan handlers should go before [7/12] I think. > --- > drivers/acpi/Makefile | 2 +- > drivers/acpi/acpi_lpss.c | 69 ++++++++++++++++++++++++++++++++-------------- > drivers/acpi/internal.h | 4 --- > 3 files changed, 50 insertions(+), 25 deletions(-) > > diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile > index 9a43893..2173e30 100644 > --- a/drivers/acpi/Makefile > +++ b/drivers/acpi/Makefile > @@ -39,7 +39,7 @@ acpi-y += processor_core.o > acpi-y += ec.o > acpi-$(CONFIG_ACPI_DOCK) += dock.o > acpi-y += pci_root.o pci_link.o pci_irq.o > -acpi-$(CONFIG_X86_INTEL_LPSS) += acpi_lpss.o > +acpi-y += acpi_lpss.o > acpi-y += acpi_platform.o > acpi-y += acpi_pnp.o > acpi-y += power.o > diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c > index 69e29f4..965428f 100644 > --- a/drivers/acpi/acpi_lpss.c > +++ b/drivers/acpi/acpi_lpss.c > @@ -24,6 +24,8 @@ > > ACPI_MODULE_NAME("acpi_lpss"); > > +#ifdef CONFIG_X86_INTEL_LPSS > + > #define LPSS_CLK_SIZE 0x04 > #define LPSS_LTR_SIZE 0x18 > > @@ -159,40 +161,50 @@ static struct lpss_device_desc byt_i2c_dev_desc = { > .shared_clock = &i2c_clock, > }; > > +#define LPSS_PTR(desc) ((unsigned long)&desc) > + > +#else > + > +#define LPSS_PTR(desc) 0 > + > +#endif > + > static const struct acpi_device_id acpi_lpss_device_ids[] = { > /* Generic LPSS devices */ > - { "INTL9C60", (unsigned long)&lpss_dma_desc }, > + { "INTL9C60", LPSS_PTR(lpss_dma_desc) }, > > /* Lynxpoint LPSS devices */ > - { "INT33C0", (unsigned long)&lpt_dev_desc }, > - { "INT33C1", (unsigned long)&lpt_dev_desc }, > - { "INT33C2", (unsigned long)&lpt_dev_desc }, > - { "INT33C3", (unsigned long)&lpt_dev_desc }, > - { "INT33C4", (unsigned long)&lpt_uart_dev_desc }, > - { "INT33C5", (unsigned long)&lpt_uart_dev_desc }, > - { "INT33C6", (unsigned long)&lpt_sdio_dev_desc }, > + { "INT33C0", LPSS_PTR(lpt_dev_desc) }, > + { "INT33C1", LPSS_PTR(lpt_dev_desc) }, > + { "INT33C2", LPSS_PTR(lpt_dev_desc) }, > + { "INT33C3", LPSS_PTR(lpt_dev_desc) }, > + { "INT33C4", LPSS_PTR(lpt_uart_dev_desc) }, > + { "INT33C5", LPSS_PTR(lpt_uart_dev_desc) }, > + { "INT33C6", LPSS_PTR(lpt_sdio_dev_desc) }, > { "INT33C7", }, > > /* BayTrail LPSS devices */ > - { "80860F09", (unsigned long)&byt_pwm_dev_desc }, > - { "80860F0A", (unsigned long)&byt_uart_dev_desc }, > - { "80860F0E", (unsigned long)&byt_spi_dev_desc }, > - { "80860F14", (unsigned long)&byt_sdio_dev_desc }, > - { "80860F41", (unsigned long)&byt_i2c_dev_desc }, > + { "80860F09", LPSS_PTR(byt_pwm_dev_desc) }, > + { "80860F0A", LPSS_PTR(byt_uart_dev_desc) }, > + { "80860F0E", LPSS_PTR(byt_spi_dev_desc) }, > + { "80860F14", LPSS_PTR(byt_sdio_dev_desc) }, > + { "80860F41", LPSS_PTR(byt_i2c_dev_desc) }, > { "INT33B2", }, > > - { "INT3430", (unsigned long)&lpt_dev_desc }, > - { "INT3431", (unsigned long)&lpt_dev_desc }, > - { "INT3432", (unsigned long)&lpt_dev_desc }, > - { "INT3433", (unsigned long)&lpt_dev_desc }, > - { "INT3434", (unsigned long)&lpt_uart_dev_desc }, > - { "INT3435", (unsigned long)&lpt_uart_dev_desc }, > - { "INT3436", (unsigned long)&lpt_sdio_dev_desc }, > + { "INT3430", LPSS_PTR(lpt_dev_desc) }, > + { "INT3431", LPSS_PTR(lpt_dev_desc) }, > + { "INT3432", LPSS_PTR(lpt_dev_desc) }, > + { "INT3433", LPSS_PTR(lpt_dev_desc) }, > + { "INT3434", LPSS_PTR(lpt_uart_dev_desc) }, > + { "INT3435", LPSS_PTR(lpt_uart_dev_desc) }, > + { "INT3436", LPSS_PTR(lpt_sdio_dev_desc) }, > { "INT3437", }, > > { } > }; > > +#ifdef CONFIG_X86_INTEL_LPSS > + > static int is_memory(struct acpi_resource *res, void *not_used) > { > struct resource r; > @@ -511,10 +523,27 @@ static struct acpi_scan_handler lpss_handler = { > .unbind = acpi_lpss_unbind, > }; > > +#endif /* CONFIG_X86_INTEL_LPSS */ > + > +static int acpi_lpss_dummy_attach(struct acpi_device *adev, > + const struct acpi_device_id *id) > +{ > + return 1; > +} > + > +static struct acpi_scan_handler lpss_dummy_handler = { > + .ids = acpi_lpss_device_ids, > + .attach = acpi_lpss_dummy_attach, > +}; > + > void __init acpi_lpss_init(void) > { > +#ifdef CONFIG_X86_INTEL_LPSS > if (!lpt_clk_init()) { > bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); > acpi_scan_add_handler(&lpss_handler); > + return; > } > +#endif > + acpi_scan_add_handler(&lpss_dummy_handler); > } > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 3a12866..40ce814 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -73,11 +73,7 @@ int acpi_debugfs_init(void); > #else > static inline void acpi_debugfs_init(void) { return; } > #endif > -#ifdef CONFIG_X86_INTEL_LPSS > void acpi_lpss_init(void); > -#else > -static inline void acpi_lpss_init(void) {} > -#endif > > acpi_status acpi_hotplug_schedule(struct acpi_device *adev, u32 src); > bool acpi_queue_hotplug_work(struct work_struct *work); > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html