This new function enhances the i2c_get_chip*() toolbox by implementing a variant that does not require a chip_addr. Instead, the desired device is pointed to by a phandle.
Signed-off-by: Philip Richard Oberfichtner pro@denx.de ---
Changes in v2: new
drivers/i2c/i2c-uclass.c | 75 ++++++++++++++++++++++++++++++++++++++++ include/i2c.h | 12 +++++++ 2 files changed, 87 insertions(+)
diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c index 8867a560bd..5405067861 100644 --- a/drivers/i2c/i2c-uclass.c +++ b/drivers/i2c/i2c-uclass.c @@ -388,6 +388,81 @@ int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len, return 0; }
+/* Find and probe I2C bus based on a chip attached to it */ +static int i2c_get_parent_bus(ofnode chip, struct udevice **devp) +{ + ofnode node; + struct udevice *dev; + int ret; + + node = ofnode_get_parent(chip); + if (!ofnode_valid(node)) + return -ENODEV; + + ret = uclass_get_device_by_ofnode(UCLASS_I2C, node, &dev); + if (ret) { + *devp = NULL; + return ret; + } + + *devp = dev; + return 0; +} + +int i2c_get_chip_by_phandle(const struct udevice *parent, const char *prop_name, + struct udevice **devp) +{ + ofnode node; + uint phandle; + struct udevice *bus, *chip; + char *dev_name; + int ret; + + debug("%s: Searching I2C chip for phandle "%s"\n", + __func__, prop_name); + + dev_name = strdup(prop_name); + if (!dev_name) { + ret = -ENOMEM; + goto err_exit; + } + + ret = dev_read_u32(parent, "i2cbcdev", &phandle); + if (ret) + goto err_exit; + + node = ofnode_get_by_phandle(phandle); + if (!ofnode_valid(node)) { + ret = -ENODEV; + goto err_exit; + } + + ret = i2c_get_parent_bus(node, &bus); + if (ret) + goto err_exit; + + ret = device_bind_driver_to_node(bus, "i2c_generic_chip_drv", + dev_name, node, &chip); + if (ret) + goto err_exit; + + ret = device_probe(chip); + if (ret) { + device_unbind(chip); + goto err_exit; + } + + debug("%s succeeded\n", __func__); + *devp = chip; + return 0; + +err_exit: + free(dev_name); + debug("%s failed, ret = %d\n", __func__, ret); + *devp = NULL; + return ret; +} + int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags, struct udevice **devp) { diff --git a/include/i2c.h b/include/i2c.h index ef3820eaba..4e59009cd9 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -537,6 +537,18 @@ int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len, int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len, struct udevice **devp);
+/** + * i2c_get_chip_by_phandle() - get a device to use to access a chip + * based on a phandle property pointing to it + * + * @parent: Parent device containing the phandle pointer + * @name: Name of phandle property in the parent device node + * @devp: Returns pointer to new device or NULL if not found + * Return: 0 on success, -ve on failure + */ +int i2c_get_chip_by_phandle(const struct udevice *parent, const char *prop_name, + struct udevice **devp); + /** * i2c_chip_of_to_plat() - Decode standard I2C platform data *