linux-kernel - [PATCH v2 2/2] i2c: core: Propagate all possible errors when requesting recovery GPIOs

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Date:   Fri, 28 May 2021 12:13:51 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Wolfram Sang <wsa+renesas@...g-engineering.com>,
        linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     Wolfram Sang <wsa@...nel.org>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Subject: [PATCH v2 2/2] i2c: core: Propagate all possible errors when requesting recovery GPIOs

If GPIO is available but we can't get it by some other, than deferred probe,
reason, propagate it to the caller.

No functional change since i2c_register_adapter() still cares only about
deferred probe.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
v2: made it as a series to avoid error when applying (LKP)
 drivers/i2c/i2c-core-base.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index ae1b1b610aca..40b8aa91db9a 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -348,19 +348,20 @@ static int i2c_gpio_init_generic_recovery(struct i2c_adapter *adap)
 	 * GPIO recovery is available
 	 */
 	if (!bri->scl_gpiod) {
-		gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
-		if (PTR_ERR(gpiod) == -EPROBE_DEFER) {
-			ret  = -EPROBE_DEFER;
+		gpiod = devm_gpiod_get_optional(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
+		if (IS_ERR(gpiod)) {
+			ret = PTR_ERR(gpiod);
 			goto cleanup_pinctrl_state;
 		}
-		if (!IS_ERR(gpiod)) {
+
+		if (gpiod) {
 			bri->scl_gpiod = gpiod;
 			bri->recover_bus = i2c_generic_scl_recovery;
 			dev_info(dev, "using generic GPIOs for recovery\n");
 		}
 	}
 
-	/* SDA GPIOD line is optional, so we care about DEFER only */
+	/* SDA GPIO line is optional */
 	if (!bri->sda_gpiod) {
 		/*
 		 * We have SCL. Pull SCL low and wait a bit so that SDA glitches
@@ -368,18 +369,19 @@ static int i2c_gpio_init_generic_recovery(struct i2c_adapter *adap)
 		 */
 		gpiod_direction_output(bri->scl_gpiod, 0);
 		udelay(10);
-		gpiod = devm_gpiod_get(dev, "sda", GPIOD_IN);
+
+		gpiod = devm_gpiod_get_optional(dev, "sda", GPIOD_IN);
 
 		/* Wait a bit in case of a SDA glitch, and then release SCL. */
 		udelay(10);
 		gpiod_direction_output(bri->scl_gpiod, 1);
 
-		if (PTR_ERR(gpiod) == -EPROBE_DEFER) {
-			ret = -EPROBE_DEFER;
+		if (IS_ERR(gpiod)) {
+			ret = PTR_ERR(gpiod);
 			goto cleanup_pinctrl_state;
 		}
-		if (!IS_ERR(gpiod))
-			bri->sda_gpiod = gpiod;
+
+		bri->sda_gpiod = gpiod;
 	}
 
 cleanup_pinctrl_state:
@@ -401,12 +403,14 @@ static int i2c_init_recovery(struct i2c_adapter *adap)
 	struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
 	bool is_error_level = true;
 	char *err_str;
+	int ret;
 
 	if (!bri)
 		return 0;
 
-	if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER)
-		return -EPROBE_DEFER;
+	ret = i2c_gpio_init_recovery(adap);
+	if (ret)
+		return ret;
 
 	if (!bri->recover_bus) {
 		err_str = "no suitable method provided";
-- 
2.30.2