i2c: core: Add new i2c_acpi_new_device helper function

By default the i2c subsys creates an i2c-client for the first I2cSerialBus
resource of an acpi_device, but some acpi_devices have multiple
I2cSerialBus resources and we may want to instantiate i2c-clients for
the others.

This commit adds a new i2c_acpi_new_device function which can be used to
create an i2c-client for any I2cSerialBus resource of an acpi_device.

Note that the other resources may even be on a different i2c bus, so just
retrieving the client address is not enough.

Here is an example DSDT excerpt from such a device:

Device (WIDR)
{
    Name (_HID, "INT33FE" /* XPOWER Battery Device */)
    Name (_CID, "INT33FE" /* XPOWER Battery Device */)
    Name (_DDN, "WC PMIC Battery Device")
<snip>
    Name (RBUF, ResourceTemplate ()
    {
        I2cSerialBusV2 (0x005E, ControllerInitiated, 0x000186A0,
            AddressingMode7Bit, "\\_SB.PCI0.I2C7",
            0x00, ResourceConsumer, , Exclusive,
            )
        I2cSerialBusV2 (0x0036, ControllerInitiated, 0x000186A0,
            AddressingMode7Bit, "\\_SB.PCI0.I2C1",
            0x00, ResourceConsumer, , Exclusive,
            )
        I2cSerialBusV2 (0x0022, ControllerInitiated, 0x00061A80,
            AddressingMode7Bit, "\\_SB.PCI0.I2C1",
            0x00, ResourceConsumer, , Exclusive,
            )
        I2cSerialBusV2 (0x0054, ControllerInitiated, 0x00061A80,
            AddressingMode7Bit, "\\_SB.PCI0.I2C1",
            0x00, ResourceConsumer, , Exclusive,
            )
        GpioInt (Level, ActiveLow, Exclusive, PullNone, 0x0000,
            "\\_SB.PCI0.I2C7.PMI5", 0x00, ResourceConsumer, ,
            )
            {   // Pin list
        0x0012
            }
        GpioInt (Edge, ActiveLow, ExclusiveAndWake, PullNone, 0x0000,
            "\\_SB.GPO1", 0x00, ResourceConsumer, ,
            )
            {   // Pin list
        0x0005
            }
        GpioInt (Level, ActiveLow, Exclusive, PullNone, 0x0000,
            "\\_SB.PCI0.I2C7.PMI5", 0x00, ResourceConsumer, ,
            )
            {   // Pin list
        0x0013
            }
    })
    Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
    {
        Return (RBUF) /* \_SB_.PCI0.I2C7.WIDR.RBUF */
    }
<snip>
}

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Hans de Goede
2017-04-05 00:03:33 +02:00
committed by Wolfram Sang
parent 417f784379
commit 605f8fc224
2 changed files with 56 additions and 0 deletions

View File

@@ -824,11 +824,18 @@ static inline const struct of_device_id
#if IS_ENABLED(CONFIG_ACPI)
u32 i2c_acpi_find_bus_speed(struct device *dev);
struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
struct i2c_board_info *info);
#else
static inline u32 i2c_acpi_find_bus_speed(struct device *dev)
{
return 0;
}
static inline struct i2c_client *i2c_acpi_new_device(struct device *dev,
int index, struct i2c_board_info *info)
{
return NULL;
}
#endif /* CONFIG_ACPI */
#endif /* _LINUX_I2C_H */