Re: [PATCH V5 08/12] ACPI: introduce dummy lpss scan handler
From: Rafael J. Wysocki
Date: Sun Apr 27 2014 - 18:06:40 EST
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.
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