[PATCH 3/9] I2C: i2c-ocores: Can add I2C devices to the bus

From: Richard Röjfors
Date: Fri Jun 05 2009 - 09:40:55 EST


There is sometimes a need for the ocores driver to add devices to the
bus when installed.

i2c_register_board_info can not always be used, because the I2C devices
are not known at an early state, they could for instance be connected
on a I2C bus on a PCI device which has the Open Cores IP.

i2c_new_device can not be used in all cases either since the resulting
bus nummer might be unknown.

The solution is the pass a list of I2C devices in the platform data to
the Open Cores driver. This is useful for MFD drivers.

Signed-off-by: Richard Röjfors <richard.rojfors.ext@xxxxxxxxxxxxxxx>
---
Index: linux-2.6.30-rc7/drivers/i2c/busses/i2c-ocores.c
===================================================================
--- linux-2.6.30-rc7/drivers/i2c/busses/i2c-ocores.c (revision 861)
+++ linux-2.6.30-rc7/drivers/i2c/busses/i2c-ocores.c (working copy)
@@ -216,6 +216,7 @@
struct ocores_i2c_platform_data *pdata;
struct resource *res, *res2;
int ret;
+ int i;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
@@ -271,6 +272,10 @@
goto add_adapter_failed;
}

+ /* add in known devices to the bus */
+ for (i = 0; i < pdata->num_devices; i++)
+ i2c_new_device(&i2c->adap, pdata->devices + i);
+
return 0;

add_adapter_failed:
Index: linux-2.6.30-rc7/Documentation/i2c/busses/i2c-ocores
===================================================================
--- linux-2.6.30-rc7/Documentation/i2c/busses/i2c-ocores (revision 861)
+++ linux-2.6.30-rc7/Documentation/i2c/busses/i2c-ocores (working copy)
@@ -20,6 +20,8 @@
dev.platform_data of the device should also point to a struct
ocores_i2c_platform_data (see linux/i2c-ocores.h) describing the
distance between registers and the input clock speed.
+There is also a possibility to attach a list of i2c_board_info which
+the i2c-ocores driver will add to the bus upon creation.

E.G. something like:

@@ -36,9 +38,24 @@
},
};

+/* optional board info */
+struct i2c_board_info ocores_i2c_board_info[] = {
+ {
+ I2C_BOARD_INFO("tsc2003", 0x48),
+ .platform_data = &tsc2003_platform_data,
+ .irq = TSC_IRQ
+ },
+ {
+ I2C_BOARD_INFO("adv7180", 0x42 >> 1),
+ .irq = ADV_IRQ
+ }
+};
+
static struct ocores_i2c_platform_data myi2c_data = {
.regstep = 2, /* two bytes between registers */
.clock_khz = 50000, /* input clock of 50MHz */
+ .devices = ocores_i2c_board_info, /* optional table of devices */
+ .num_devices = ARRAY_SIZE(ocores_i2c_board_info), /* table size */
};

static struct platform_device myi2c = {
Index: linux-2.6.30-rc7/include/linux/i2c-ocores.h
===================================================================
--- linux-2.6.30-rc7/include/linux/i2c-ocores.h (revision 861)
+++ linux-2.6.30-rc7/include/linux/i2c-ocores.h (working copy)
@@ -14,6 +14,8 @@
struct ocores_i2c_platform_data {
u32 regstep; /* distance between registers */
u32 clock_khz; /* input clock in kHz */
+ u8 num_devices; /* number of devices in the devices list */
+ struct i2c_board_info const *devices; /* devices connected to the bus */
};

#endif /* _LINUX_I2C_OCORES_H */
--
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