From: Andreas Werner Date: Sun, 22 Mar 2015 16:35:52 +0000 (+0100) Subject: can: flexcan: Deferred on Regulator return EPROBE_DEFER X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=555828ef45f825d6ee06559f0304163550eed380;p=openwrt%2Fstaging%2Fblogic.git can: flexcan: Deferred on Regulator return EPROBE_DEFER Return EPROBE_DEFER if Regulator returns EPROBE_DEFER If the Flexcan driver is built into kernel and a regulator is used to enable the CAN transceiver, the Flexcan driver may not use the regulator. When initializing the Flexcan device with a regulator defined in the device tree, but not initialized, the regulator subsystem returns EPROBE_DEFER, hence the Flexcan init fails. The solution for this is to return EPROBE_DEFER if regulator is not initialized and wait until the regulator is initialized. Signed-off-by: Andreas Werner Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index ee944ae6bb96..ad0a7e8c2c2b 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -1157,12 +1157,19 @@ static int flexcan_probe(struct platform_device *pdev) const struct flexcan_devtype_data *devtype_data; struct net_device *dev; struct flexcan_priv *priv; + struct regulator *reg_xceiver; struct resource *mem; struct clk *clk_ipg = NULL, *clk_per = NULL; void __iomem *base; int err, irq; u32 clock_freq = 0; + reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver"); + if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER) + return -EPROBE_DEFER; + else if (IS_ERR(reg_xceiver)) + reg_xceiver = NULL; + if (pdev->dev.of_node) of_property_read_u32(pdev->dev.of_node, "clock-frequency", &clock_freq); @@ -1223,9 +1230,7 @@ static int flexcan_probe(struct platform_device *pdev) priv->pdata = dev_get_platdata(&pdev->dev); priv->devtype_data = devtype_data; - priv->reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver"); - if (IS_ERR(priv->reg_xceiver)) - priv->reg_xceiver = NULL; + priv->reg_xceiver = reg_xceiver; netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);