Patch "i2c: imx: defer probe if bus recovery GPIOs are not ready" has been added to the 4.8-stable tree

Patch "i2c: imx: defer probe if bus recovery GPIOs are not ready" has been added to the 4.8-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

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

to the 4.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     i2c-imx-defer-probe-if-bus-recovery-gpios-are-not-ready.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 533169d164c6b4c8571d0d48779f6ff6be593d72 Mon Sep 17 00:00:00 2001
From: Stefan Agner <stefan@agner.ch>
Date: Mon, 26 Sep 2016 17:18:58 -0700
Subject: i2c: imx: defer probe if bus recovery GPIOs are not ready
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Stefan Agner <stefan@agner.ch>

commit 533169d164c6b4c8571d0d48779f6ff6be593d72 upstream.

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 <stefan@agner.ch>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/i2c/busses/i2c-imx.c |   11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -996,10 +996,13 @@ static void i2c_imx_init_recovery_info(s
 	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;
 	}


Patches currently in stable-queue which might be from stefan@agner.ch are

queue-4.8/i2c-imx-defer-probe-if-bus-recovery-gpios-are-not-ready.patch