[PATCH] i2c-mux-gpio: use deferred probing with the device tree

Ionut Nicu
2013-10-08T13:20:18Z

If the i2c-parent bus driver is not loaded, returning
-EINVAL will force people to unload and then reload the
module again to get it working.

Also of_get_named_gpio could return -E_PROBE_DEFER or
another error code. This error should be passed further
instead of being ignored.

Signed-off-by: Ionut Nicu <ioan.nicu.ext-OYasijW0DpE@public.gmane.org>
---
drivers/i2c/muxes/i2c-mux-gpio.c | 12 ++++++++----
1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index 5d4a99b..6370b47 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -66,7 +66,7 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,
struct device_node *adapter_np, *child;
struct i2c_adapter *adapter;
unsigned *values, *gpios;
- int i = 0;
+ int i = 0, ret;

if (!np)
return -ENODEV;
@@ -79,7 +79,7 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,
adapter = of_find_i2c_adapter_by_node(adapter_np);
if (!adapter) {
dev_err(&pdev->dev, "Cannot find parent bus\n");
- return -ENODEV;
+ return -EPROBE_DEFER;
}
mux->data.parent = i2c_adapter_id(adapter);
put_device(&adapter->dev);
@@ -116,8 +116,12 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,
return -ENOMEM;
}

- for (i = 0; i < mux->data.n_gpios; i++)
- gpios[i] = of_get_named_gpio(np, "mux-gpios", i);
+ for (i = 0; i < mux->data.n_gpios; i++) {
+ ret = of_get_named_gpio(np, "mux-gpios", i);
+ if (ret < 0)
+ return ret;
+ gpios[i] = ret;
+ }

mux->data.gpios = gpios;

--
1.7.1