eeepc-laptop: disp attribute should be write-only

Currently, reading from the disp attribute fails with "No such device",
which is misleading. According to CMSG table on acpi4asus project site,
no models have a getter method corresponding to SDSP. Change the file
permission to disallow reads.

If some joker changes the permission to permit reads, then return -EIO
to be consistent with sysfs' behaviour when no show() method is
provided.

Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index 4226e535273874fb06aea0344c4c8ce00a8b957c..2c65a3772968434be2ee51867ff934b4c9978a24 100644 (file)
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -380,7 +380,7 @@ static ssize_t store_sys_acpi(int cm, const char *buf, size_t count)
        if (rv > 0)
                value = set_acpi(cm, value);
        if (value < 0)
-               return value;
+               return -EIO;
        return rv;
 }
 
@@ -389,11 +389,11 @@ static ssize_t show_sys_acpi(int cm, char *buf)
        int value = get_acpi(cm);
 
        if (value < 0)
-               return value;
+               return -EIO;
        return sprintf(buf, "%d\n", value);
 }
 
-#define EEEPC_CREATE_DEVICE_ATTR(_name, _cm)                           \
+#define EEEPC_CREATE_DEVICE_ATTR(_name, _mode, _cm)                    \
        static ssize_t show_##_name(struct device *dev,                 \
                                    struct device_attribute *attr,      \
                                    char *buf)                          \
@@ -409,14 +409,14 @@ static ssize_t show_sys_acpi(int cm, char *buf)
        static struct device_attribute dev_attr_##_name = {             \
                .attr = {                                               \
                        .name = __stringify(_name),                     \
-                       .mode = 0644 },                                 \
+                       .mode = _mode },                                \
                .show   = show_##_name,                                 \
                .store  = store_##_name,                                \
        }
 
-EEEPC_CREATE_DEVICE_ATTR(camera, CM_ASL_CAMERA);
-EEEPC_CREATE_DEVICE_ATTR(cardr, CM_ASL_CARDREADER);
-EEEPC_CREATE_DEVICE_ATTR(disp, CM_ASL_DISPLAYSWITCH);
+EEEPC_CREATE_DEVICE_ATTR(camera, 0644, CM_ASL_CAMERA);
+EEEPC_CREATE_DEVICE_ATTR(cardr, 0644, CM_ASL_CARDREADER);
+EEEPC_CREATE_DEVICE_ATTR(disp, 0200, CM_ASL_DISPLAYSWITCH);
 
 struct eeepc_cpufv {
        int num;