i2c: imx: defer probe if bus recovery GPIOs are not ready

Some SoC might load the GPIO driver after the I2C driver and using the I2C bus recovery mechanism via GPIOs. In this case it is crucial to defer probing if the GPIO request functions do so, otherwise the I2C driver gets loaded without recovery mechanisms enabled. Signed-off-by: Stefan Agner <[email protected]> Acked-by: Uwe Kleine-König <[email protected]> Acked-by: Li Yang <[email protected]> Signed-off-by: Wolfram Sang <[email protected]> Cc: [email protected]
npcomplete13 · Oct 25, 2016 · 533169d · 533169d
1 parent 171e23e
commit 533169d
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
@@ -1009,10 +1009,13 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 	rinfo->sda_gpio = of_get_named_gpio(pdev->dev.of_node, "sda-gpios", 0);
 	rinfo->scl_gpio = of_get_named_gpio(pdev->dev.of_node, "scl-gpios", 0);
 
-	if (!gpio_is_valid(rinfo->sda_gpio) ||
-	    !gpio_is_valid(rinfo->scl_gpio) ||
-	    IS_ERR(i2c_imx->pinctrl_pins_default) ||
-	    IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
+	if (rinfo->sda_gpio == -EPROBE_DEFER ||
+	    rinfo->scl_gpio == -EPROBE_DEFER) {
+		return -EPROBE_DEFER;
+	} else if (!gpio_is_valid(rinfo->sda_gpio) ||
+		   !gpio_is_valid(rinfo->scl_gpio) ||
+		   IS_ERR(i2c_imx->pinctrl_pins_default) ||
+		   IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
 		dev_dbg(&pdev->dev, "recovery information incomplete\n");
 		return 0;
 	}