pinctrl: sx150x: Fix pinctrl enablement order bug

I encountered bug in SX1502 expander driver in 5.7.7. Here is relevant
DTS part:

compatible = "semtech,sx1502q";
gpio4_cfg_pins: gpio2-cfg {
                         pins = "gpio5";
                         output-high;
     };

And part of OOPS:

[    0.673996] [<c023cfa6>] (gpiochip_get_data) from [<c023b235>]
(sx150x_gpio_direction_output+0xd)
[    0.683259] [<c023b235>] (sx150x_gpio_direction_output) from
[<c023b363>] (sx150x_pinconf_set+0x)
[    0.692796] [<c023b363>] (sx150x_pinconf_set) from [<c0238fef>]
(pinconf_apply_setting+0x39/0x7e)
[    0.701635] [<c0238fef>] (pinconf_apply_setting) from [<c0236c77>]
(pinctrl_commit_state+0xa5/0x)
[    0.710648] [<c0236c77>] (pinctrl_commit_state) from [<c0237e03>]
(pinctrl_enable+0xff/0x1d4)
[    0.719139] [<c0237e03>] (pinctrl_enable) from [<c023b791>]
(sx150x_probe+0x1a3/0x358)
[    0.727027] [<c023b791>] (sx150x_probe) from [<c02c38bf>]
(i2c_device_probe+0x1bb/0x1dc)

The problem is that sx150x_pinconf_set uses sx150x_gpio_direction_output
but gpio is not setup yet. Patch below fixes it but I'm not sure whether
is it correct.

Link: https://lore.kernel.org/r/f32130bf-cfd4-b1bf-538c-dbc9ee2d947a@eaxlabs.cz
Signed-off-by: Martin DEVERA <devik@eaxlabs.cz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/pinctrl-sx150x.c b/drivers/pinctrl/pinctrl-sx150x.c
index b325a136ac4889cc6d15338531bfdb54c3f6c379..c110f780407bd0c156f422fd88b2afb8fc1389d7 100644 (file)
--- a/drivers/pinctrl/pinctrl-sx150x.c
+++ b/drivers/pinctrl/pinctrl-sx150x.c
@@ -1154,12 +1154,6 @@ static int sx150x_probe(struct i2c_client *client,
                return ret;
        }
 
-       ret = pinctrl_enable(pctl->pctldev);
-       if (ret) {
-               dev_err(dev, "Failed to enable pinctrl device\n");
-               return ret;
-       }
-
        /* Register GPIO controller */
        pctl->gpio.base = -1;
        pctl->gpio.ngpio = pctl->data->npins;
@@ -1238,6 +1232,17 @@ static int sx150x_probe(struct i2c_client *client,
        if (ret)
                return ret;
 
+       /*
+        * Pin control functions need to be enabled AFTER registering the
+        * GPIO chip because sx150x_pinconf_set() calls
+        * sx150x_gpio_direction_output().
+        */
+       ret = pinctrl_enable(pctl->pctldev);
+       if (ret) {
+               dev_err(dev, "Failed to enable pinctrl device\n");
+               return ret;
+       }
+
        ret = gpiochip_add_pin_range(&pctl->gpio, dev_name(dev),
                                     0, 0, pctl->data->npins);
        if (ret)