1 files changed, 47 insertions, 11 deletions

diff --git a/drivers/platform/x86/panasonic-laptop.c b/drivers/platform/x86/panasonic-laptop.c
index cf845ee1c7b1..ebd81846e2d5 100644
--- a/drivers/platform/x86/panasonic-laptop.c
+++ b/drivers/platform/x86/panasonic-laptop.c
@@ -337,7 +337,8 @@ static int acpi_pcc_retrieve_biosdata(struct pcc_acpi *pcc)
 	}
 
 	if (pcc->num_sifr < hkey->package.count) {
-		pr_err("SQTY reports bad SINF length\n");
+		pr_err("SQTY reports bad SINF length SQTY: %lu SINF-pkg-count: %u\n",
+		       pcc->num_sifr, hkey->package.count);
 		status = AE_ERROR;
 		goto end;
 	}
@@ -773,6 +774,24 @@ static DEVICE_ATTR_RW(dc_brightness);
 static DEVICE_ATTR_RW(current_brightness);
 static DEVICE_ATTR_RW(cdpower);
 
+static umode_t pcc_sysfs_is_visible(struct kobject *kobj, struct attribute *attr, int idx)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct acpi_device *acpi = to_acpi_device(dev);
+	struct pcc_acpi *pcc = acpi_driver_data(acpi);
+
+	if (attr == &dev_attr_mute.attr)
+		return (pcc->num_sifr > SINF_MUTE) ? attr->mode : 0;
+
+	if (attr == &dev_attr_eco_mode.attr)
+		return (pcc->num_sifr > SINF_ECO_MODE) ? attr->mode : 0;
+
+	if (attr == &dev_attr_current_brightness.attr)
+		return (pcc->num_sifr > SINF_CUR_BRIGHT) ? attr->mode : 0;
+
+	return attr->mode;
+}
+
 static struct attribute *pcc_sysfs_entries[] = {
 	&dev_attr_numbatt.attr,
 	&dev_attr_lcdtype.attr,
@@ -787,8 +806,9 @@ static struct attribute *pcc_sysfs_entries[] = {
 };
 
 static const struct attribute_group pcc_attr_group = {
-	.name	= NULL,		/* put in device directory */
-	.attrs	= pcc_sysfs_entries,
+	.name		= NULL,		/* put in device directory */
+	.attrs		= pcc_sysfs_entries,
+	.is_visible	= pcc_sysfs_is_visible,
 };
 
 
@@ -941,12 +961,15 @@ static int acpi_pcc_hotkey_resume(struct device *dev)
 	if (!pcc)
 		return -EINVAL;
 
-	acpi_pcc_write_sset(pcc, SINF_MUTE, pcc->mute);
-	acpi_pcc_write_sset(pcc, SINF_ECO_MODE, pcc->eco_mode);
+	if (pcc->num_sifr > SINF_MUTE)
+		acpi_pcc_write_sset(pcc, SINF_MUTE, pcc->mute);
+	if (pcc->num_sifr > SINF_ECO_MODE)
+		acpi_pcc_write_sset(pcc, SINF_ECO_MODE, pcc->eco_mode);
 	acpi_pcc_write_sset(pcc, SINF_STICKY_KEY, pcc->sticky_key);
 	acpi_pcc_write_sset(pcc, SINF_AC_CUR_BRIGHT, pcc->ac_brightness);
 	acpi_pcc_write_sset(pcc, SINF_DC_CUR_BRIGHT, pcc->dc_brightness);
-	acpi_pcc_write_sset(pcc, SINF_CUR_BRIGHT, pcc->current_brightness);
+	if (pcc->num_sifr > SINF_CUR_BRIGHT)
+		acpi_pcc_write_sset(pcc, SINF_CUR_BRIGHT, pcc->current_brightness);
 
 	return 0;
 }
@@ -963,11 +986,21 @@ static int acpi_pcc_hotkey_add(struct acpi_device *device)
 
 	num_sifr = acpi_pcc_get_sqty(device);
 
-	if (num_sifr < 0 || num_sifr > 255) {
-		pr_err("num_sifr out of range");
+	/*
+	 * pcc->sinf is expected to at least have the AC+DC brightness entries.
+	 * Accesses to higher SINF entries are checked against num_sifr.
+	 */
+	if (num_sifr <= SINF_DC_CUR_BRIGHT || num_sifr > 255) {
+		pr_err("num_sifr %d out of range %d - 255\n", num_sifr, SINF_DC_CUR_BRIGHT + 1);
 		return -ENODEV;
 	}
 
+	/*
+	 * Some DSDT-s have an off-by-one bug where the SINF package count is
+	 * one higher than the SQTY reported value, allocate 1 entry extra.
+	 */
+	num_sifr++;
+
 	pcc = kzalloc(sizeof(struct pcc_acpi), GFP_KERNEL);
 	if (!pcc) {
 		pr_err("Couldn't allocate mem for pcc");
@@ -1020,11 +1053,14 @@ static int acpi_pcc_hotkey_add(struct acpi_device *device)
 	acpi_pcc_write_sset(pcc, SINF_STICKY_KEY, 0);
 	pcc->sticky_key = 0;
 
-	pcc->eco_mode = pcc->sinf[SINF_ECO_MODE];
-	pcc->mute = pcc->sinf[SINF_MUTE];
 	pcc->ac_brightness = pcc->sinf[SINF_AC_CUR_BRIGHT];
 	pcc->dc_brightness = pcc->sinf[SINF_DC_CUR_BRIGHT];
-	pcc->current_brightness = pcc->sinf[SINF_CUR_BRIGHT];
+	if (pcc->num_sifr > SINF_MUTE)
+		pcc->mute = pcc->sinf[SINF_MUTE];
+	if (pcc->num_sifr > SINF_ECO_MODE)
+		pcc->eco_mode = pcc->sinf[SINF_ECO_MODE];
+	if (pcc->num_sifr > SINF_CUR_BRIGHT)
+		pcc->current_brightness = pcc->sinf[SINF_CUR_BRIGHT];
 
 	/* add sysfs attributes */
 	result = sysfs_create_group(&device->dev.kobj, &pcc_attr_group);