Merge branch 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:
 "Here is the 4.9 pull request from I2C including:

   - centralized error messages when registering to the core
   - improved lockdep annotations to prevent false positives
   - DT support for muxes, gates, and arbitrators
   - bus speeds can now be obtained from ACPI
   - i2c-octeon got refactored and now supports ThunderX SoCs, too
   - i2c-tegra and i2c-designware got a bigger bunch of updates
   - a couple of standard driver fixes and improvements"

* 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits)
  i2c: axxia: disable clks in case of failure in probe
  i2c: octeon: thunderx: Limit register access retries
  i2c: uniphier-f: fix misdetection of incomplete STOP condition
  gpio: pca953x: variable 'id' was used twice
  i2c: i801: Add support for Kaby Lake PCH-H
  gpio: pca953x: fix an incorrect lockdep warning
  i2c: add a warning to i2c_adapter_depth()
  lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible
  i2c: export i2c_adapter_depth()
  i2c: rk3x: Fix variable 'min_total_ns' unused warning
  i2c: rk3x: Fix sparse warning
  i2c / ACPI: Do not touch an I2C device if it belongs to another adapter
  i2c: octeon: Fix high-level controller status check
  i2c: octeon: Avoid sending STOP during recovery
  i2c: octeon: Fix set SCL recovery function
  i2c: rcar: add support for r8a7796 (R-Car M3-W)
  i2c: imx: make bus recovery through pinctrl optional
  i2c: meson: add gxbb compatible string
  i2c: uniphier-f: set the adapter to master mode when probing
  i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
  ...

1 files changed, 23 insertions, 12 deletions

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 1844bc9f7cd5..592a8f26a708 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -984,11 +984,24 @@ static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
 	pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
 }
 
-static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
+/*
+ * We switch SCL and SDA to their GPIO function and do some bitbanging
+ * for bus recovery. These alternative pinmux settings can be
+ * described in the device tree by a separate pinctrl state "gpio". If
+ * this is missing this is not a big problem, the only implication is
+ * that we can't do bus recovery.
+ */
+static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 		struct platform_device *pdev)
 {
 	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
 
+	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
+	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
+		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
+		return PTR_ERR(i2c_imx->pinctrl);
+	}
+
 	i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
 			PINCTRL_STATE_DEFAULT);
 	i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
@@ -1001,7 +1014,7 @@ static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 	    IS_ERR(i2c_imx->pinctrl_pins_default) ||
 	    IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
 		dev_dbg(&pdev->dev, "recovery information incomplete\n");
-		return;
+		return 0;
 	}
 
 	dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n",
@@ -1011,6 +1024,8 @@ static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 	rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
 	rinfo->recover_bus = i2c_generic_gpio_recovery;
 	i2c_imx->adapter.bus_recovery_info = rinfo;
+
+	return 0;
 }
 
 static u32 i2c_imx_func(struct i2c_adapter *adapter)
@@ -1081,12 +1096,6 @@ static int i2c_imx_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
-	if (IS_ERR(i2c_imx->pinctrl)) {
-		ret = PTR_ERR(i2c_imx->pinctrl);
-		goto clk_disable;
-	}
-
 	/* Request IRQ */
 	ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
 				pdev->name, i2c_imx);
@@ -1125,14 +1134,16 @@ static int i2c_imx_probe(struct platform_device *pdev)
 			i2c_imx, IMX_I2C_I2CR);
 	imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
 
-	i2c_imx_init_recovery_info(i2c_imx, pdev);
+	/* Init optional bus recovery function */
+	ret = i2c_imx_init_recovery_info(i2c_imx, pdev);
+	/* Give it another chance if pinctrl used is not ready yet */
+	if (ret == -EPROBE_DEFER)
+		goto rpm_disable;
 
 	/* Add I2C adapter */
 	ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "registration failed\n");
+	if (ret < 0)
 		goto rpm_disable;
-	}
 
 	pm_runtime_mark_last_busy(&pdev->dev);
 	pm_runtime_put_autosuspend(&pdev->dev);