ASoC: Intel: Skylake: Shield against no-NHLT configurations

Some configurations expose no NHLT table at all within their
/sys/firmware/acpi/tables. To prevent NULL-dereference errors from
occurring, adjust probe flow and append additional safety checks in
functions involved in NHLT lifecycle.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200305145314.32579-5-cezary.rojewski@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/intel/skylake/skl-nhlt.c b/sound/soc/intel/skylake/skl-nhlt.c
index 19f328d71f244687cf66e38a00d602665824bcaa..d9c8f5cb389e33289c9c57b6e330725e8f75568c 100644 (file)
--- a/sound/soc/intel/skylake/skl-nhlt.c
+++ b/sound/soc/intel/skylake/skl-nhlt.c
@@ -182,7 +182,8 @@ void skl_nhlt_remove_sysfs(struct skl_dev *skl)
 {
        struct device *dev = &skl->pci->dev;
 
-       sysfs_remove_file(&dev->kobj, &dev_attr_platform_id.attr);
+       if (skl->nhlt)
+               sysfs_remove_file(&dev->kobj, &dev_attr_platform_id.attr);
 }
 
 /*

diff --git a/sound/soc/intel/skylake/skl.c b/sound/soc/intel/skylake/skl.c
index e2e531c96dd1091f83b8185e6299cc6a655595e6..7ad8a75759bde79eca77f3c520963b5baea9f122 100644 (file)
--- a/sound/soc/intel/skylake/skl.c
+++ b/sound/soc/intel/skylake/skl.c
@@ -633,6 +633,9 @@ static int skl_clock_device_register(struct skl_dev *skl)
        struct platform_device_info pdevinfo = {NULL};
        struct skl_clk_pdata *clk_pdata;
 
+       if (!skl->nhlt)
+               return 0;
+
        clk_pdata = devm_kzalloc(&skl->pci->dev, sizeof(*clk_pdata),
                                                        GFP_KERNEL);
        if (!clk_pdata)
@@ -1074,7 +1077,8 @@ out_dsp_free:
 out_clk_free:
        skl_clock_device_unregister(skl);
 out_nhlt_free:
-       intel_nhlt_free(skl->nhlt);
+       if (skl->nhlt)
+               intel_nhlt_free(skl->nhlt);
 out_free:
        skl_free(bus);
 
@@ -1123,7 +1127,8 @@ static void skl_remove(struct pci_dev *pci)
        skl_dmic_device_unregister(skl);
        skl_clock_device_unregister(skl);
        skl_nhlt_remove_sysfs(skl);
-       intel_nhlt_free(skl->nhlt);
+       if (skl->nhlt)
+               intel_nhlt_free(skl->nhlt);
        skl_free(bus);
        dev_set_drvdata(&pci->dev, NULL);
 }