[RFC PATCH 3/4] i2c: core: treat EPROBE_DEFER when acquiring SCL/SDA GPIOs

From: Codrin Ciubotariu
Date: Fri Jun 19 2020 - 10:21:19 EST


Even if I2C bus GPIO recovery is optional, devm_gpiod_get() can return
-EPROBE_DEFER, so we should at least treat that. This ends up with
i2c_register_adapter() to be able to return -EPROBE_DEFER.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
---
drivers/i2c/i2c-core-base.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 4ee29fec4e93..f8d9f2048ca8 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -368,15 +368,16 @@ static int i2c_gpio_init_recovery(struct i2c_adapter *adap)
return i2c_gpio_init_generic_recovery(adap);
}

-static void i2c_init_recovery(struct i2c_adapter *adap)
+static int i2c_init_recovery(struct i2c_adapter *adap)
{
struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
char *err_str;

if (!bri)
- return;
+ return 0;

- i2c_gpio_init_recovery(adap);
+ if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;

if (!bri->recover_bus) {
err_str = "no recover_bus() found";
@@ -392,7 +393,7 @@ static void i2c_init_recovery(struct i2c_adapter *adap)
if (gpiod_get_direction(bri->sda_gpiod) == 0)
bri->set_sda = set_sda_gpio_value;
}
- return;
+ return 0;
}

if (bri->recover_bus == i2c_generic_scl_recovery) {
@@ -407,10 +408,12 @@ static void i2c_init_recovery(struct i2c_adapter *adap)
}
}

- return;
+ return 0;
err:
dev_err(&adap->dev, "Not using recovery: %s\n", err_str);
adap->bus_recovery_info = NULL;
+
+ return 0;
}

static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client)
@@ -1476,7 +1479,9 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
"Failed to create compatibility class link\n");
#endif

- i2c_init_recovery(adap);
+ res = i2c_init_recovery(adap);
+ if (res == -EPROBE_DEFER)
+ goto out_link;

/* create pre-declared device nodes */
of_i2c_register_devices(adap);
@@ -1493,6 +1498,11 @@ static int i2c_register_adapter(struct i2c_adapter *adap)

return 0;

+out_link:
+#ifdef CONFIG_I2C_COMPAT
+ class_compat_remove_link(i2c_adapter_compat_class, &adap->dev,
+ adap->dev.parent);
+#endif
out_reg:
init_completion(&adap->dev_released);
device_unregister(&adap->dev);
--
2.25.1