[Added Jerry as he found out a problem when acpi_i2c is being build as a
module, this should solve it as well.]
On Tue, Aug 20, 2013 at 01:25:27AM +0200, Rafael J. Wysocki wrote:
> On Monday, August 19, 2013 04:56:19 PM Stephen Warren wrote:
> > On 08/19/2013 05:04 PM, Rafael J. Wysocki wrote:
> > > On Monday, August 19, 2013 03:19:18 PM Wolfram Sang wrote:
> > >> I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
> > >> that it is much cleaner to have this in the core. This also removes a
> > >> circular dependency between the helpers and the core, and so we can
> > >> finally register child nodes in the core instead of doing this manually
> > >> in each driver. So, fix the drivers and documentation, too.
> > >
> > > Perhaps we should do the analogous for ACPI then?
Here is the ACPI version based on the current patch from Wolfram (there is
a compile error because of missing dummy implementation of
of_i2c_register_devices())
From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Subject: [PATCH] i2c: move ACPI helpers into the core
This follows what has already been done for the DeviceTree helpers. Move
the ACPI helpers from drivers/acpi/acpi_i2c.c to the I2C core and update
documentation accordingly.
This also solves a problem reported by Jerry Snitselaar that we can't build
the ACPI I2C helpers as a module.
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
---
Documentation/acpi/enumeration.txt | 15 +---
drivers/acpi/Kconfig | 6 --
drivers/acpi/Makefile | 1 -
drivers/acpi/acpi_i2c.c | 103 ----------------------------
drivers/i2c/busses/i2c-designware-platdrv.c | 1 -
drivers/i2c/i2c-core.c | 91 ++++++++++++++++++++++++
include/linux/i2c.h | 6 --
7 files changed, 94 insertions(+), 129 deletions(-)
delete mode 100644 drivers/acpi/acpi_i2c.c
diff --git a/Documentation/acpi/enumeration.txt b/Documentation/acpi/enumeration.txt
index 958266e..d977778 100644
--- a/Documentation/acpi/enumeration.txt
+++ b/Documentation/acpi/enumeration.txt
@@ -228,18 +228,9 @@ ACPI handle like:
I2C serial bus support
~~~~~~~~~~~~~~~~~~~~~~
The slaves behind I2C bus controller only need to add the ACPI IDs like
-with the platform and SPI drivers. However the I2C bus controller driver
-needs to call acpi_i2c_register_devices() after it has added the adapter.
-
-An I2C bus (controller) driver does:
-
- ...
- ret = i2c_add_numbered_adapter(adapter);
- if (ret)
- /* handle error */
-
- /* Enumerate the slave devices behind this bus via ACPI */
- acpi_i2c_register_devices(adapter);
+with the platform and SPI drivers. The I2C core automatically enumerates
+any slave devices behind the controller device once the adapter is
+registered.
Below is an example of how to add ACPI support to the existing mpu3050
input driver:
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 100bd72..4e0162f 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -180,12 +180,6 @@ config ACPI_DOCK
This driver supports ACPI-controlled docking stations and removable
drive bays such as the IBM Ultrabay and the Dell Module Bay.
-config ACPI_I2C
- def_tristate I2C
- depends on I2C
- help
- ACPI I2C enumeration support.
-
config ACPI_PROCESSOR
tristate "Processor"
select THERMAL
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 81dbeb8..cdaf68b 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -73,7 +73,6 @@ obj-$(CONFIG_ACPI_HED) += hed.o
obj-$(CONFIG_ACPI_EC_DEBUGFS) += ec_sys.o
obj-$(CONFIG_ACPI_CUSTOM_METHOD)+= custom_method.o
obj-$(CONFIG_ACPI_BGRT) += bgrt.o
-obj-$(CONFIG_ACPI_I2C) += acpi_i2c.o
# processor has its own "processor." module_param namespace
processor-y := processor_driver.o processor_throttling.o
diff --git a/drivers/acpi/acpi_i2c.c b/drivers/acpi/acpi_i2c.c
deleted file mode 100644
index a82c762..0000000
--- a/drivers/acpi/acpi_i2c.c
+++ /dev/null
@@ -1,103 +0,0 @@
-/*
- * ACPI I2C enumeration support
- *
- * Copyright (C) 2012, Intel Corporation
- * Author: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/acpi.h>
-#include <linux/device.h>
-#include <linux/export.h>
-#include <linux/i2c.h>
-#include <linux/ioport.h>
-
-ACPI_MODULE_NAME("i2c");
-
-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.handle = handle;
- 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;
-
- strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
- if (!i2c_new_device(adapter, &info)) {
- 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
- * @adapter: 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 *adapter)
-{
- acpi_handle handle;
- acpi_status status;
-
- handle = ACPI_HANDLE(adapter->dev.parent);
- if (!handle)
- return;
-
- status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
- acpi_i2c_add_device, NULL,
- adapter, NULL);
- if (ACPI_FAILURE(status))
- dev_warn(&adapter->dev, "failed to enumerate I2C slaves\n");
-}
-EXPORT_SYMBOL_GPL(acpi_i2c_register_devices);
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 27ea436..1240fd6 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -171,7 +171,6 @@ static int dw_i2c_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "failure adding adapter\n");
return r;
}
- acpi_i2c_register_devices(adap);
pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
pm_runtime_use_autosuspend(&pdev->dev);
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 321b7ca..cc80432 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1056,6 +1056,96 @@ struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
EXPORT_SYMBOL(of_find_i2c_device_by_node);
#endif /* CONFIG_OF */
+/* ACPI support code */
+
+#ifdef 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.handle = handle;
+ 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;
+
+ strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
+ if (!i2c_new_device(adapter, &info)) {
+ 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
+ * @adapter: 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 *adapter)
+{
+ acpi_handle handle;
+ acpi_status status;
+
+ handle = ACPI_HANDLE(adapter->dev.parent);
+ if (!handle)
+ return;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+ acpi_i2c_add_device, NULL,
+ adapter, NULL);
+ if (ACPI_FAILURE(status))
+ dev_warn(&adapter->dev, "failed to enumerate I2C slaves\n");
+}
+#else
+static inline void acpi_i2c_register_devices(struct i2c_adapter *adapter) {}
+#endif /* CONFIG_ACPI */
+
static int i2c_do_add_adapter(struct i2c_driver *driver,
struct i2c_adapter *adap)
{
@@ -1161,6 +1251,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
exit_recovery:
/* create pre-declared device nodes */
of_i2c_register_devices(adap);
+ acpi_i2c_register_devices(adap);
if (adap->nr < __i2c_first_dynamic_bus_num)
i2c_scan_static_board_info(adap);
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 2189189..7670d99 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -562,10 +562,4 @@ static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node
}
#endif /* CONFIG_OF */
-#if IS_ENABLED(CONFIG_ACPI_I2C)
-extern void acpi_i2c_register_devices(struct i2c_adapter *adap);
-#else
-static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) {}
-#endif
-
#endif /* _LINUX_I2C_H */
--
1.8.4.rc2
--
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