[PATCH v23 02/13] power: reset: reboot-mode: Support up to 3 magic values per mode

ARM PSCI vendor-specific resets, require a 32-bit reset_type and a 64-bit
cookie as arguments. This cannot be implemented via the reboot-mode
framework, which supports a single 32-bit argument as magic value.

Extend the reboot-mode framework to support up to three 32-bit arguments
as magic, per reboot-mode.

Signed-off-by: Shivendra Pratap <[email protected]>
---
 drivers/power/reset/nvmem-reboot-mode.c  | 10 ++++----
 drivers/power/reset/qcom-pon.c           |  8 ++++---
 drivers/power/reset/reboot-mode.c        | 41 +++++++++++++++++++++-----------
 drivers/power/reset/syscon-reboot-mode.c |  8 ++++---
 include/linux/reboot-mode.h              |  4 +++-
 5 files changed, 46 insertions(+), 25 deletions(-)

diff --git a/drivers/power/reset/nvmem-reboot-mode.c b/drivers/power/reset/nvmem-reboot-mode.c
index d260715fccf6..ac69b5f39fb4 100644
--- a/drivers/power/reset/nvmem-reboot-mode.c
+++ b/drivers/power/reset/nvmem-reboot-mode.c
@@ -17,14 +17,16 @@ struct nvmem_reboot_mode {
 	struct nvmem_cell *cell;
 };
 
-static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot,
-				    unsigned int magic)
+static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, u32 *magic, int count)
 {
 	struct nvmem_reboot_mode *nvmem_rbm;
 	size_t buf_len;
 	void *buf;
 	int ret;
 
+	if (count != 1)
+		return -EINVAL;
+
 	nvmem_rbm = container_of(reboot, struct nvmem_reboot_mode, reboot);
 
 	buf = nvmem_cell_read(nvmem_rbm->cell, &buf_len);
@@ -32,10 +34,10 @@ static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot,
 		return PTR_ERR(buf);
 	kfree(buf);
 
-	if (buf_len > sizeof(magic))
+	if (buf_len > sizeof(magic[0]))
 		return -EINVAL;
 
-	ret = nvmem_cell_write(nvmem_rbm->cell, &magic, buf_len);
+	ret = nvmem_cell_write(nvmem_rbm->cell, &magic[0], buf_len);
 	if (ret < 0)
 		dev_err(reboot->dev, "update reboot mode bits failed\n");
 
diff --git a/drivers/power/reset/qcom-pon.c b/drivers/power/reset/qcom-pon.c
index 7e108982a582..a508ab26d03f 100644
--- a/drivers/power/reset/qcom-pon.c
+++ b/drivers/power/reset/qcom-pon.c
@@ -27,17 +27,19 @@ struct qcom_pon {
 	long reason_shift;
 };
 
-static int qcom_pon_reboot_mode_write(struct reboot_mode_driver *reboot,
-				    unsigned int magic)
+static int qcom_pon_reboot_mode_write(struct reboot_mode_driver *reboot, u32 *magic, int count)
 {
 	struct qcom_pon *pon = container_of
 			(reboot, struct qcom_pon, reboot_mode);
 	int ret;
 
+	if (count != 1)
+		return -EINVAL;
+
 	ret = regmap_update_bits(pon->regmap,
 				 pon->baseaddr + PON_SOFT_RB_SPARE,
 				 GENMASK(7, pon->reason_shift),
-				 magic << pon->reason_shift);
+				 magic[0] << pon->reason_shift);
 	if (ret < 0)
 		dev_err(pon->dev, "update reboot mode bits failed\n");
 
diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c
index 7a74f72a8313..db2129c72341 100644
--- a/drivers/power/reset/reboot-mode.c
+++ b/drivers/power/reset/reboot-mode.c
@@ -22,7 +22,8 @@
 
 struct mode_info {
 	const char *mode;
-	u32 magic;
+	u32 magic[3];
+	int count;
 	struct list_head list;
 };
 
@@ -74,8 +75,7 @@ static const struct class reboot_mode_class = {
 	.dev_groups = reboot_mode_groups,
 };
 
-static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
-					  const char *cmd)
+static struct mode_info *get_reboot_mode_info(struct reboot_mode_driver *reboot, const char *cmd)
 {
 	const char *normal = "normal";
 	struct mode_info *info;
@@ -86,11 +86,11 @@ static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
 
 	list_for_each_entry(info, &reboot->head, list)
 		if (!strcmp(info->mode, cmd))
-			return info->magic;
+			return info;
 
 	/* try to match again, replacing characters impossible in DT */
 	if (strscpy(cmd_, cmd, sizeof(cmd_)) == -E2BIG)
-		return 0;
+		return NULL;
 
 	strreplace(cmd_, ' ', '-');
 	strreplace(cmd_, ',', '-');
@@ -98,21 +98,21 @@ static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
 
 	list_for_each_entry(info, &reboot->head, list)
 		if (!strcmp(info->mode, cmd_))
-			return info->magic;
+			return info;
 
-	return 0;
+	return NULL;
 }
 
 static int reboot_mode_notify(struct notifier_block *this,
 			      unsigned long mode, void *cmd)
 {
 	struct reboot_mode_driver *reboot;
-	unsigned int magic;
+	struct mode_info *info;
 
 	reboot = container_of(this, struct reboot_mode_driver, reboot_notifier);
-	magic = get_reboot_mode_magic(reboot, cmd);
-	if (magic)
-		reboot->write(reboot, magic);
+	info = get_reboot_mode_info(reboot, cmd);
+	if (info && info->count > 0)
+		reboot->write(reboot, info->magic, info->count);
 
 	return NOTIFY_DONE;
 }
@@ -175,16 +175,22 @@ int reboot_mode_register(struct reboot_mode_driver *reboot)
 	struct property *prop;
 	struct device_node *np = reboot->dev->of_node;
 	size_t len = strlen(PREFIX);
-	u32 magic;
+	u32 magic[3];
+	int count;
 	int ret;
 
 	INIT_LIST_HEAD(&reboot->head);
 
 	for_each_property_of_node(np, prop) {
+		memset(magic, 0, sizeof(magic));
+
 		if (strncmp(prop->name, PREFIX, len))
 			continue;
 
-		if (device_property_read_u32(reboot->dev, prop->name, &magic)) {
+		count = device_property_count_u32(reboot->dev, prop->name);
+
+		if (count <= 0 || count > ARRAY_SIZE(magic) ||
+		    device_property_read_u32_array(reboot->dev, prop->name, magic, count)) {
 			pr_debug("reboot mode %s without magic number\n", prop->name);
 			continue;
 		}
@@ -195,7 +201,14 @@ int reboot_mode_register(struct reboot_mode_driver *reboot)
 			goto error;
 		}
 
-		info->magic = magic;
+		if (!memchr_inv(magic, 0, count * sizeof(u32))) {
+			pr_debug("reboot mode %s with zero magic values\n", prop->name);
+			info->count = -1;
+		} else {
+			memcpy(info->magic, magic, count * sizeof(u32));
+			info->count = count;
+		}
+
 		info->mode = kstrdup_const(prop->name + len, GFP_KERNEL);
 		if (!info->mode) {
 			ret =  -ENOMEM;
diff --git a/drivers/power/reset/syscon-reboot-mode.c b/drivers/power/reset/syscon-reboot-mode.c
index e0772c9f70f7..983b1fbf614a 100644
--- a/drivers/power/reset/syscon-reboot-mode.c
+++ b/drivers/power/reset/syscon-reboot-mode.c
@@ -20,16 +20,18 @@ struct syscon_reboot_mode {
 	u32 mask;
 };
 
-static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot,
-				    unsigned int magic)
+static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot, u32 *magic, int count)
 {
 	struct syscon_reboot_mode *syscon_rbm;
 	int ret;
 
+	if (count != 1)
+		return -EINVAL;
+
 	syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot);
 
 	ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset,
-				 syscon_rbm->mask, magic);
+				 syscon_rbm->mask, magic[0]);
 	if (ret < 0)
 		dev_err(reboot->dev, "update reboot mode bits failed\n");
 
diff --git a/include/linux/reboot-mode.h b/include/linux/reboot-mode.h
index 4a2abb38d1d6..34a81e4b4f95 100644
--- a/include/linux/reboot-mode.h
+++ b/include/linux/reboot-mode.h
@@ -2,10 +2,12 @@
 #ifndef __REBOOT_MODE_H__
 #define __REBOOT_MODE_H__
 
+#include <linux/types.h>
+
 struct reboot_mode_driver {
 	struct device *dev;
 	struct list_head head;
-	int (*write)(struct reboot_mode_driver *reboot, unsigned int magic);
+	int (*write)(struct reboot_mode_driver *reboot, u32 *magic, int count);
 	struct notifier_block reboot_notifier;
 };
 

-- 
2.34.1