In DRA72x EVM, by default slave 1 is connected to the onboard phy, but slave 2 pins are also muxed with video input module which is controlled by pcf857x gpio and currently to select slave 0 to connect to phy gpio hogging is used, but with omap2plus_defconfig the pcf857x gpio is built as module. So when using NFS on DRA72x EVM, board doesn't boot as gpio hogging do not set proper gpio state to connect slave 0 to phy as it is built as module and you do not see any errors for not setting gpio and just mentions dhcp reply not got. To solve this issue, introducing "select-slave-gpio" in DT when gpio based muxing is required. This will through a warning when vgpio get fails and returns probe defer. When gpio-pcf857x module is installed, cpsw probes again and ethernet becomes functional. Verified this on DRA72x with pcf as module and ramdisk [1] Signed-off-by: Mugunthan V N <mugunthanvnm@xxxxxx> --- This patch is texted on DRA72x, Logs [1] and pushed a branch [2] [1]: http://pastebin.ubuntu.com/12244652/ [2]: git://git.ti.com/~mugunthanvnm/ti-linux-kernel/linux.git cpsw-gpio-optional --- Documentation/devicetree/bindings/net/cpsw.txt | 3 +++ drivers/net/ethernet/ti/cpsw.c | 10 ++++++++++ 2 files changed, 13 insertions(+) diff --git a/Documentation/devicetree/bindings/net/cpsw.txt b/Documentation/devicetree/bindings/net/cpsw.txt index 33fe846..cb693aa 100644 --- a/Documentation/devicetree/bindings/net/cpsw.txt +++ b/Documentation/devicetree/bindings/net/cpsw.txt @@ -26,6 +26,9 @@ Optional properties: - dual_emac : Specifies Switch to act as Dual EMAC - syscon : Phandle to the system control device node, which is the control module device of the am33x +- select-slave-gpio : Should be added if a gpio line is required to + select which slave is connected to phy + Slave Properties: Required properties: diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c index 8fc90f1..ce965ad 100644 --- a/drivers/net/ethernet/ti/cpsw.c +++ b/drivers/net/ethernet/ti/cpsw.c @@ -29,6 +29,7 @@ #include <linux/workqueue.h> #include <linux/delay.h> #include <linux/pm_runtime.h> +#include <linux/gpio.h> #include <linux/of.h> #include <linux/of_net.h> #include <linux/of_device.h> @@ -2207,6 +2208,7 @@ static int cpsw_probe(struct platform_device *pdev) void __iomem *ss_regs; struct resource *res, *ss_res; const struct of_device_id *of_id; + struct gpio_desc *select_slave; u32 slave_offset, sliver_offset, slave_size; int ret = 0, i; int irq; @@ -2232,6 +2234,14 @@ static int cpsw_probe(struct platform_device *pdev) goto clean_ndev_ret; } + select_slave = devm_gpiod_get_optional(&pdev->dev, "select-slave", + GPIOD_OUT_LOW); + if (IS_ERR(select_slave)) { + ret = PTR_ERR(select_slave); + dev_err(&pdev->dev, "gpio request failed, ret %d\n", ret); + goto clean_ndev_ret; + } + /* * This may be required here for child devices. */ -- 2.5.0.474.g3a9835b -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
