Merge tag 'imx-fixes-4.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo...

Merge "The i.MX fixes for 4.1, 3rd round" from Shawn Guo:

It includes a couple of fixes for i.MX6 GPC code to let the new kernel
be able to boot with old DTBs:

 - Booting v4.1-rc kernel with old DTBs will fail with a fat warning
   (require low-level debug to be seen), due to the adoption of stacked
   IRQ domain.  The first fix improves the situation by allowing kernel
   boot up with old DTBs, although suspend/resume still breaks.

 - Booting new kernel with old DTBs that do not have power-domain info
   will result in a hang.  The second patch fixes the hang by skipping
   the kernel power-domain registration if DTB has no power-domain info.

* tag 'imx-fixes-4.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
  ARM: imx6: gpc: don't register power domain if DT data is missing
  ARM: imx6: allow booting with old DT

diff --git a/arch/arm/mach-imx/gpc.c b/arch/arm/mach-imx/gpc.c
index 4d60005..6d0893a 100644 (file)
--- a/arch/arm/mach-imx/gpc.c
+++ b/arch/arm/mach-imx/gpc.c
@@ -280,9 +280,15 @@ void __init imx_gpc_check_dt(void)
        struct device_node *np;
 
        np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
-       if (WARN_ON(!np ||
-                   !of_find_property(np, "interrupt-controller", NULL)))
-               pr_warn("Outdated DT detected, system is about to crash!!!\n");
+       if (WARN_ON(!np))
+               return;
+
+       if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
+               pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
+
+               /* map GPC, so that at least CPUidle and WARs keep working */
+               gpc_base = of_iomap(np, 0);
+       }
 }
 
 #ifdef CONFIG_PM_GENERIC_DOMAINS
@@ -443,6 +449,10 @@ static int imx_gpc_probe(struct platform_device *pdev)
        struct regulator *pu_reg;
        int ret;
 
+       /* bail out if DT too old and doesn't provide the necessary info */
+       if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells"))
+               return 0;
+
        pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
        if (PTR_ERR(pu_reg) == -ENODEV)
                pu_reg = NULL;