From: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx> In preparation for the Arria10 ECC modules, check the status of the parent in the device tree to ensure the block is enabled. Skip if no parent phandle is set in the device tree. Signed-off-by: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx> --- v2 No change v3 Move check into validate_parent_available(). v4 Match maintainer's changes v5 Change "parent" string to "altr,ecc-parent" --- drivers/edac/altera_edac.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c index 6f5d586..0101dd0 100644 --- a/drivers/edac/altera_edac.c +++ b/drivers/edac/altera_edac.c @@ -1125,6 +1125,20 @@ static void altr_edac_a10_irq_handler(struct irq_desc *desc) chained_irq_exit(chip, desc); } +static int validate_parent_available(struct device_node *np) +{ + struct device_node *parent; + int ret = 0; + + /* Ensure parent device is enabled if parent node exists */ + parent = of_parse_phandle(np, "altr,ecc-parent", 0); + if (parent && !of_device_is_available(parent)) + ret = -ENODEV; + + of_node_put(parent); + return ret; +} + static int altr_edac_a10_device_add(struct altr_arria10_edac *edac, struct device_node *np) { @@ -1146,6 +1160,9 @@ static int altr_edac_a10_device_add(struct altr_arria10_edac *edac, if (IS_ERR_OR_NULL(prv)) return -ENODEV; + if (validate_parent_available(np)) + return -ENODEV; + if (!devres_open_group(edac->dev, altr_edac_a10_device_add, GFP_KERNEL)) return -ENOMEM; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html