summaryrefslogtreecommitdiffstats
path: root/drivers/i2c
diff options
context:
space:
mode:
authorStefan Agner <stefan@agner.ch>2016-09-27 02:18:58 +0200
committerWolfram Sang <wsa@the-dreams.de>2016-10-25 12:15:00 +0200
commit533169d164c6b4c8571d0d48779f6ff6be593d72 (patch)
treef5fcc56599fbca43c8bbd8bac0c8c1281fe3d40a /drivers/i2c
parenti2c: designware: Avoid aborted transfers with fast reacting I2C slaves (diff)
downloadlinux-533169d164c6b4c8571d0d48779f6ff6be593d72.tar.xz
linux-533169d164c6b4c8571d0d48779f6ff6be593d72.zip
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 <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> Cc: stable@kernel.org
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-imx.c11
1 files changed, 7 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 592a8f26a708..47fc1f1acff7 100644
--- 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;
}