From 5d98e61d337c181f199a6cb864569cc4e116ef4c Mon Sep 17 00:00:00 2001 From: Lan Tianyu Date: Tue, 20 May 2014 20:59:23 +0800 Subject: I2C/ACPI: Add i2c ACPI operation region support ACPI 5.0 spec(5.5.2.4.5) defines GenericSerialBus(i2c, spi, uart) operation region. It allows ACPI aml code able to access such kind of devices to implement some ACPI standard method. ACPI Spec defines some access attribute to associate with i2c protocol. AttribQuick Read/Write Quick Protocol AttribSendReceive Send/Receive Byte Protocol AttribByte Read/Write Byte Protocol AttribWord Read/Write Word Protocol AttribBlock Read/Write Block Protocol AttribBytes Read/Write N-Bytes Protocol AttribProcessCall Process Call Protocol AttribBlockProcessCall Write Block-Read Block Process Call Protocol AttribRawBytes Raw Read/Write N-BytesProtocol AttribRawProcessBytes Raw Process Call Protocol On the Asus T100TA, Bios use GenericSerialBus operation region to access i2c device to get battery info. Sample code From Asus T100TA Scope (_SB.I2C1) { Name (UMPC, ResourceTemplate () { I2cSerialBus (0x0066, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , ) }) ... OperationRegion (DVUM, GenericSerialBus, Zero, 0x0100) Field (DVUM, BufferAcc, NoLock, Preserve) { Connection (UMPC), Offset (0x81), AccessAs (BufferAcc, AttribBytes (0x3E)), FGC0, 8 } ... } Device (BATC) { Name (_HID, EisaId ("PNP0C0A")) // _HID: Hardware ID Name (_UID, One) // _UID: Unique ID ... Method (_BST, 0, NotSerialized) // _BST: Battery Status { If (LEqual (AVBL, One)) { Store (FGC0, BFFG) If (LNotEqual (STAT, One)) { ShiftRight (CHST, 0x04, Local0) And (Local0, 0x03, Local0) If (LOr (LEqual (Local0, One), LEqual (Local0, 0x02))) { Store (0x02, Local1) } ... } The i2c operation region is defined under I2C1 scope. _BST method under battery device BATC read battery status from the field "FCG0". The request would be sent to i2c operation region handler. This patch is to add i2c ACPI operation region support. Due to there are only "Byte" and "Bytes" protocol access on the Asus T100TA, other protocols have not been tested. About RawBytes and RawProcessBytes protocol, they needs specific drivers to interpret reference data from AML code according ACPI 5.0 SPEC(5.5.2.4.5.3.9 and 5.5.2.4.5.3.10). So far, not found such case and will add when find real case. Signed-off-by: Lan Tianyu Reviewed-by: Mika Westerberg Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 7c7f4b856bad..e25cb84cb297 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1293,6 +1293,7 @@ exit_recovery: /* create pre-declared device nodes */ of_i2c_register_devices(adap); acpi_i2c_register_devices(adap); + acpi_i2c_install_space_handler(adap); if (adap->nr < __i2c_first_dynamic_bus_num) i2c_scan_static_board_info(adap); @@ -1466,6 +1467,7 @@ void i2c_del_adapter(struct i2c_adapter *adap) return; } + acpi_i2c_remove_space_handler(adap); /* Tell drivers about this removal */ mutex_lock(&core_lock); bus_for_each_drv(&i2c_bus_type, NULL, adap, -- cgit v1.2.3 From da3c6647ee08711c7edc28d7fea4ad69fc5ffcca Mon Sep 17 00:00:00 2001 From: Lan Tianyu Date: Tue, 20 May 2014 20:59:24 +0800 Subject: I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI config Clean up ACPI related code in the i2c core and add CONFIG_I2C_ACPI to enable I2C ACPI code. Current there is a race between removing I2C ACPI operation region and ACPI AML code accessing. So make i2c core built-in if CONFIG_I2C_ACPI is set. Reviewed-by: Mika Westerberg Signed-off-by: Lan Tianyu Signed-off-by: Wolfram Sang --- drivers/i2c/Kconfig | 18 +++++++++- drivers/i2c/Makefile | 2 +- drivers/i2c/i2c-acpi.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/i2c/i2c-core.c | 95 -------------------------------------------------- include/linux/i2c.h | 4 ++- 5 files changed, 110 insertions(+), 98 deletions(-) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig index 7b7ea320a258..3e3b680dc007 100644 --- a/drivers/i2c/Kconfig +++ b/drivers/i2c/Kconfig @@ -2,7 +2,9 @@ # I2C subsystem configuration # -menuconfig I2C +menu "I2C support" + +config I2C tristate "I2C support" select RT_MUTEXES ---help--- @@ -21,6 +23,18 @@ menuconfig I2C This I2C support can also be built as a module. If so, the module will be called i2c-core. +config I2C_ACPI + bool "I2C ACPI support" + select I2C + depends on ACPI + default y + help + Say Y here if you want to enable ACPI I2C support. This includes support + for automatic enumeration of I2C slave devices and support for ACPI I2C + Operation Regions. Operation Regions allow firmware (BIOS) code to + access I2C slave devices, such as smart batteries through an I2C host + controller driver. + if I2C config I2C_BOARDINFO @@ -124,3 +138,5 @@ config I2C_DEBUG_BUS on. endif # I2C + +endmenu diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 80db3073aa84..a1f590cbb435 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -3,7 +3,7 @@ # i2ccore-y := i2c-core.o -i2ccore-$(CONFIG_ACPI) += i2c-acpi.o +i2ccore-$(CONFIG_I2C_ACPI) += i2c-acpi.o obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o obj-$(CONFIG_I2C) += i2ccore.o diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c index f7f4c89c09b3..e8b61967334b 100644 --- a/drivers/i2c/i2c-acpi.c +++ b/drivers/i2c/i2c-acpi.c @@ -37,6 +37,95 @@ struct gsb_buffer { }; } __packed; +static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data) +{ + struct i2c_board_info *info = data; + + if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { + struct acpi_resource_i2c_serialbus *sb; + + sb = &ares->data.i2c_serial_bus; + if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) { + info->addr = sb->slave_address; + if (sb->access_mode == ACPI_I2C_10BIT_MODE) + info->flags |= I2C_CLIENT_TEN; + } + } else if (info->irq < 0) { + struct resource r; + + if (acpi_dev_resource_interrupt(ares, 0, &r)) + info->irq = r.start; + } + + /* Tell the ACPI core to skip this resource */ + return 1; +} + +static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, + void *data, void **return_value) +{ + struct i2c_adapter *adapter = data; + struct list_head resource_list; + struct i2c_board_info info; + struct acpi_device *adev; + int ret; + + if (acpi_bus_get_device(handle, &adev)) + return AE_OK; + if (acpi_bus_get_status(adev) || !adev->status.present) + return AE_OK; + + memset(&info, 0, sizeof(info)); + info.acpi_node.companion = adev; + info.irq = -1; + + INIT_LIST_HEAD(&resource_list); + ret = acpi_dev_get_resources(adev, &resource_list, + acpi_i2c_add_resource, &info); + acpi_dev_free_resource_list(&resource_list); + + if (ret < 0 || !info.addr) + return AE_OK; + + adev->power.flags.ignore_parent = true; + strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); + if (!i2c_new_device(adapter, &info)) { + adev->power.flags.ignore_parent = false; + dev_err(&adapter->dev, + "failed to add I2C device %s from ACPI\n", + dev_name(&adev->dev)); + } + + return AE_OK; +} + +/** + * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter + * @adap: pointer to adapter + * + * Enumerate all I2C slave devices behind this adapter by walking the ACPI + * namespace. When a device is found it will be added to the Linux device + * model and bound to the corresponding ACPI handle. + */ +void acpi_i2c_register_devices(struct i2c_adapter *adap) +{ + acpi_handle handle; + acpi_status status; + + if (!adap->dev.parent) + return; + + handle = ACPI_HANDLE(adap->dev.parent); + if (!handle) + return; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, + acpi_i2c_add_device, NULL, + adap, NULL); + if (ACPI_FAILURE(status)) + dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); +} + static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, u8 cmd, u8 *data, u8 data_len) { diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index e25cb84cb297..4ccff114b147 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1092,101 +1092,6 @@ EXPORT_SYMBOL(of_find_i2c_adapter_by_node); static void of_i2c_register_devices(struct i2c_adapter *adap) { } #endif /* CONFIG_OF */ -/* ACPI support code */ - -#if IS_ENABLED(CONFIG_ACPI) -static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data) -{ - struct i2c_board_info *info = data; - - if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { - struct acpi_resource_i2c_serialbus *sb; - - sb = &ares->data.i2c_serial_bus; - if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) { - info->addr = sb->slave_address; - if (sb->access_mode == ACPI_I2C_10BIT_MODE) - info->flags |= I2C_CLIENT_TEN; - } - } else if (info->irq < 0) { - struct resource r; - - if (acpi_dev_resource_interrupt(ares, 0, &r)) - info->irq = r.start; - } - - /* Tell the ACPI core to skip this resource */ - return 1; -} - -static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, - void *data, void **return_value) -{ - struct i2c_adapter *adapter = data; - struct list_head resource_list; - struct i2c_board_info info; - struct acpi_device *adev; - int ret; - - if (acpi_bus_get_device(handle, &adev)) - return AE_OK; - if (acpi_bus_get_status(adev) || !adev->status.present) - return AE_OK; - - memset(&info, 0, sizeof(info)); - info.acpi_node.companion = adev; - info.irq = -1; - - INIT_LIST_HEAD(&resource_list); - ret = acpi_dev_get_resources(adev, &resource_list, - acpi_i2c_add_resource, &info); - acpi_dev_free_resource_list(&resource_list); - - if (ret < 0 || !info.addr) - return AE_OK; - - adev->power.flags.ignore_parent = true; - strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); - if (!i2c_new_device(adapter, &info)) { - adev->power.flags.ignore_parent = false; - dev_err(&adapter->dev, - "failed to add I2C device %s from ACPI\n", - dev_name(&adev->dev)); - } - - return AE_OK; -} - -/** - * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter - * @adap: pointer to adapter - * - * Enumerate all I2C slave devices behind this adapter by walking the ACPI - * namespace. When a device is found it will be added to the Linux device - * model and bound to the corresponding ACPI handle. - */ -static void acpi_i2c_register_devices(struct i2c_adapter *adap) -{ - acpi_handle handle; - acpi_status status; - - if (!adap->dev.parent) - return; - - handle = ACPI_HANDLE(adap->dev.parent); - if (!handle) - return; - - status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, - acpi_i2c_add_device, NULL, - adap, NULL); - if (ACPI_FAILURE(status)) - dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); -} -#else -static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) {} -#endif /* CONFIG_ACPI */ - static int i2c_do_add_adapter(struct i2c_driver *driver, struct i2c_adapter *adap) { diff --git a/include/linux/i2c.h b/include/linux/i2c.h index f7a939a2cb56..ea507665896c 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -577,10 +577,12 @@ static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node } #endif /* CONFIG_OF */ -#ifdef CONFIG_ACPI +#ifdef CONFIG_I2C_ACPI int acpi_i2c_install_space_handler(struct i2c_adapter *adapter); void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter); +void acpi_i2c_register_devices(struct i2c_adapter *adap); #else +static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { } static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) { } static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) -- cgit v1.2.3 From 4555227211ae867d8f8ec9eb5182273f58b648c0 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 10 Jul 2014 13:46:21 +0200 Subject: i2c: add debug info when class instantiation was dropped We have a warning already when support for old-fashioned class based instantiation is about to be dropped somewhen soon from a driver. Let's have another one when it was actually dropped. This allows to remove the cruft a little earlier and still let users know what happened in the rare case they are missing devices after the change. However, there is enough interest to get rid of class based instantiation rather sooner than later because it improves boot up time. Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 4ccff114b147..a1eeb8a5d3f8 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1915,6 +1915,16 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) if (!driver->detect || !address_list) return 0; + /* Warn that the adapter lost class based instantiation */ + if (adapter->class == I2C_CLASS_DEPRECATED) { + dev_dbg(&adapter->dev, + "This adapter dropped support for I2C classes and " + "won't auto-detect %s devices anymore. If you need it, check " + "'Documentation/i2c/instantiating-devices' for alternatives.\n", + driver->driver.name); + return 0; + } + /* Stop here if the classes do not match */ if (!(adapter->class & driver->class)) return 0; -- cgit v1.2.3