If the dma controller is not yet probed, defer i2c probe.
The error path in probe was slightly modified (no functional change)
to avoid triggering this WARN_ON():
"cg-pll0-div1 already disabled
WARNING: CPU: 1 PID: 1 at drivers/clk/clk.c:828 clk_core_disable+0xa8/0xb0"

Signed-off-by: Laurentiu Tudor <laurentiu.tu...@nxp.com>
---
 drivers/i2c/busses/i2c-imx.c | 45 +++++++++++++++++++++---------------
 1 file changed, 27 insertions(+), 18 deletions(-)

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index fa9ad53845d9..5a28d25ff9b6 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -273,8 +273,8 @@ static inline unsigned char imx_i2c_read_reg(struct 
imx_i2c_struct *i2c_imx,
 }
 
 /* Functions for DMA support */
-static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
-                                               dma_addr_t phy_addr)
+static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
+                              dma_addr_t phy_addr)
 {
        struct imx_i2c_dma *dma;
        struct dma_slave_config dma_sconfig;
@@ -283,11 +283,12 @@ static void i2c_imx_dma_request(struct imx_i2c_struct 
*i2c_imx,
 
        dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
        if (!dma)
-               return;
+               return -ENOMEM;
 
-       dma->chan_tx = dma_request_slave_channel(dev, "tx");
-       if (!dma->chan_tx) {
-               dev_dbg(dev, "can't request DMA tx channel\n");
+       dma->chan_tx = dma_request_slave_channel_reason(dev, "tx");
+       if (IS_ERR(dma->chan_tx)) {
+               ret = PTR_ERR(dma->chan_tx);
+               dma->chan_tx = NULL;
                goto fail_al;
        }
 
@@ -301,10 +302,10 @@ static void i2c_imx_dma_request(struct imx_i2c_struct 
*i2c_imx,
                dev_dbg(dev, "can't configure tx channel\n");
                goto fail_tx;
        }
-
-       dma->chan_rx = dma_request_slave_channel(dev, "rx");
-       if (!dma->chan_rx) {
-               dev_dbg(dev, "can't request DMA rx channel\n");
+       dma->chan_rx = dma_request_slave_channel_reason(dev, "rx");
+       if (IS_ERR(dma->chan_rx)) {
+               ret = PTR_ERR(dma->chan_rx);
+               dma->chan_rx = NULL;
                goto fail_tx;
        }
 
@@ -324,7 +325,7 @@ static void i2c_imx_dma_request(struct imx_i2c_struct 
*i2c_imx,
        dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
                dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
 
-       return;
+       return 0;
 
 fail_rx:
        dma_release_channel(dma->chan_rx);
@@ -332,7 +333,8 @@ static void i2c_imx_dma_request(struct imx_i2c_struct 
*i2c_imx,
        dma_release_channel(dma->chan_tx);
 fail_al:
        devm_kfree(dev, dma);
-       dev_info(dev, "can't use DMA, using PIO instead.\n");
+
+       return ret;
 }
 
 static void i2c_imx_dma_callback(void *arg)
@@ -1106,7 +1108,8 @@ static int i2c_imx_probe(struct platform_device *pdev)
                                pdev->name, i2c_imx);
        if (ret) {
                dev_err(&pdev->dev, "can't claim irq %d\n", irq);
-               goto clk_disable;
+               clk_disable_unprepare(i2c_imx->clk);
+               return ret;
        }
 
        /* Init queue */
@@ -1156,17 +1159,25 @@ static int i2c_imx_probe(struct platform_device *pdev)
        pm_runtime_mark_last_busy(&pdev->dev);
        pm_runtime_put_autosuspend(&pdev->dev);
 
+       /* Init DMA config if supported */
+       ret = i2c_imx_dma_request(i2c_imx, phy_addr);
+       if (ret) {
+               if (ret != -EPROBE_DEFER)
+                       dev_info(&pdev->dev, "can't use DMA, using PIO 
instead.\n");
+               else
+                       goto del_adapter;
+       }
+
        dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
        dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
        dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
                i2c_imx->adapter.name);
        dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
 
-       /* Init DMA config if supported */
-       i2c_imx_dma_request(i2c_imx, phy_addr);
-
        return 0;   /* Return OK */
 
+del_adapter:
+       i2c_del_adapter(&i2c_imx->adapter);
 clk_notifier_unregister:
        clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
 rpm_disable:
@@ -1175,8 +1186,6 @@ static int i2c_imx_probe(struct platform_device *pdev)
        pm_runtime_set_suspended(&pdev->dev);
        pm_runtime_dont_use_autosuspend(&pdev->dev);
 
-clk_disable:
-       clk_disable_unprepare(i2c_imx->clk);
        return ret;
 }
 
-- 
2.17.1

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