i2c: imx: improve the error handling in i2c_imx_dma_request()

Improve the error handling in i2c_imx_dma_request() and let it return an error
indication that the caller then can handle accordingly.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index e28ef494dac8538d90b30e171eb2555737f5acac..09b12454766956aef6ae7ffe2e6a22c8bb2d31f2 100644 (file)
--- 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;
@@ -283,7 +283,7 @@ 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_chan(dev, "tx");
        if (IS_ERR(dma->chan_tx)) {
@@ -328,7 +328,7 @@ 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);
@@ -336,6 +336,8 @@ fail_tx:
        dma_release_channel(dma->chan_tx);
 fail_al:
        devm_kfree(dev, dma);
+       /* return successfully if there is no dma support */
+       return ret == -ENODEV ? 0 : ret;
 }
 
 static void i2c_imx_dma_callback(void *arg)
@@ -1163,11 +1165,13 @@ static int i2c_imx_probe(struct platform_device *pdev)
        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);
+       ret = i2c_imx_dma_request(i2c_imx, phy_addr);
+       if (ret < 0)
+               goto clk_notifier_unregister;
 
+       dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
        return 0;   /* Return OK */
 
 clk_notifier_unregister: