of_i2c: Add Sparc support.
Signed-off-by: David S. Miller <[EMAIL PROTECTED]>
---
arch/sparc/include/asm/of_i2c.h | 67 +++++++++++++++++++++++++++++++++++++++
drivers/of/Kconfig | 2 +-
2 files changed, 68 insertions(+), 1 deletions(-)
create mode 100644 arch/sparc/include/asm/of_i2c.h
diff --git a/arch/sparc/include/asm/of_i2c.h b/arch/sparc/include/asm/of_i2c.h
new file mode 100644
index 0000000..93c7c05
--- /dev/null
+++ b/arch/sparc/include/asm/of_i2c.h
@@ -0,0 +1,67 @@
+#ifndef _ASM_SPARC_OF_I2C_H
+#define _ASM_SPARC_OF_I2C_H
+
+/* In my copy of the I2C bindings for IEEE1275 the register value is
+ * encoded as a 2-cell value:
+ *
+ * Bit # 33222222 22221111 11111100 00000000
+ * 10987654 32109876 54321098 76543210
+ *
+ * bus: 00000000 00000000 00000000 bbbbbbbb
+ * address: 00000000 00000000 00000sss sssssss0
+ *
+ * where:
+ * bbbbbbbb 8-bit unsigned number representing
+ * the I2C bus address within this I2C bus
+ * controller node
+ * ssssssssss 10-bit unsigned number representing the
+ * slave address
+ *
+ * When doing I2C transfers to a device the low bit of the address
+ * indicates whether the transfer is a read or a write, and the upper
+ * bits indicate the device address.
+ *
+ * The Linux I2C layer wants device addresses which elide this
+ * direction bit. Thus we should shift the OF provided reg property
+ * address down by one bit.
+ */
+static inline int of_i2c_fetch_addr(struct i2c_board_info *bp,
+ struct device_node *client_node,
+ struct device_node *adap_node,
+ int num_addr_cells)
+{
+ const u32 *addr;
+ int len;
+
+ addr = of_get_property(client_node, "reg", &len);
+ if (!addr)
+ goto out_inval;
+
+ if (len < (num_addr_cells * sizeof(int)))
+ goto out_inval;
+
+ if (addr[num_addr_cells - 1] > (1 << 10) - 1)
+ goto out_inval;
+
+ switch (num_addr_cells) {
+ case 1:
+ bp->addr = addr[0];
+ break;
+
+ case 2:
+ /* XXX cell 0 contains bus number XXX */
+ bp->addr = addr[1];
+ break;
+
+ default:
+ goto out_inval;
+ }
+
+ return 0;
+
+out_inval:
+ printk(KERN_ERR "of-i2c: invalid i2c device entry\n");
+ return -EINVAL;
+}
+
+#endif /* _ASM_SPARC_OF_I2C_H */
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index f821dbc..493c717 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -10,7 +10,7 @@ config OF_GPIO
config OF_I2C
def_tristate I2C
- depends on PPC_OF && I2C
+ depends on I2C
help
OpenFirmware I2C accessors
--
1.5.6.5.GIT
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