From 95d9ffd7b678414cc79365c8d2be0d12c326a7ad Mon Sep 17 00:00:00 2001
From: Samuel Holland <samuel@sholland.org>
Date: Sun, 24 Oct 2021 21:00:10 -0500
Subject: [PATCH] power: pmic: axp: Implement poweroff via sysreset

The AXP PMICs have the ability to power off the system. The existing
code for this is duplicated for each PMIC variant, and uses the legacy
non-DM "pmic_bus" interface. When SYSRESET is enabled, this can all be
replaced with a sysreset device using the DM_PMIC interface.

Since the trigger bit is the same on all PMIC variants, use the register
definitions from the oldest supported PMIC.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
 drivers/power/pmic/Kconfig |  2 ++
 drivers/power/pmic/axp.c   | 49 +++++++++++++++++++++++++++++++++++++-
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/drivers/power/pmic/Kconfig b/drivers/power/pmic/Kconfig
index 92e2ace279..b9fda428df 100644
--- a/drivers/power/pmic/Kconfig
+++ b/drivers/power/pmic/Kconfig
@@ -66,6 +66,8 @@ config PMIC_ACT8846
 config PMIC_AXP
 	bool "Enable Driver Model for X-Powers AXP PMICs"
 	depends on DM_I2C
+	select SYSRESET_CMD_POWEROFF if SYSRESET && CMD_POWEROFF
+	imply CMD_POWEROFF if SYSRESET
 	help
 	  This config enables driver-model PMIC uclass features for
 	  X-Powers AXP152, AXP2xx, and AXP8xx PMICs.
diff --git a/drivers/power/pmic/axp.c b/drivers/power/pmic/axp.c
index 74c94bdb47..0f2b24a8b5 100644
--- a/drivers/power/pmic/axp.c
+++ b/drivers/power/pmic/axp.c
@@ -1,8 +1,37 @@
 // SPDX-License-Identifier: GPL-2.0+
 
+#include <axp_pmic.h>
 #include <dm.h>
+#include <dm/lists.h>
 #include <i2c.h>
 #include <power/pmic.h>
+#include <sysreset.h>
+
+#if CONFIG_IS_ENABLED(SYSRESET)
+static int axp_sysreset_request(struct udevice *dev, enum sysreset_t type)
+{
+	int ret;
+
+	if (type != SYSRESET_POWER_OFF)
+		return -EPROTONOSUPPORT;
+
+	ret = pmic_clrsetbits(dev->parent, AXP152_SHUTDOWN, 0, AXP152_POWEROFF);
+	if (ret < 0)
+		return ret;
+
+	return -EINPROGRESS;
+}
+
+static struct sysreset_ops axp_sysreset_ops = {
+	.request	= axp_sysreset_request,
+};
+
+U_BOOT_DRIVER(axp_sysreset) = {
+	.name		= "axp_sysreset",
+	.id		= UCLASS_SYSRESET,
+	.ops		= &axp_sysreset_ops,
+};
+#endif
 
 static int axp_pmic_reg_count(struct udevice *dev)
 {
@@ -16,6 +45,24 @@ static struct dm_pmic_ops axp_pmic_ops = {
 	.write		= dm_i2c_write,
 };
 
+static int axp_pmic_bind(struct udevice *dev)
+{
+	int ret;
+
+	ret = dm_scan_fdt_dev(dev);
+	if (ret)
+		return ret;
+
+	if (CONFIG_IS_ENABLED(SYSRESET)) {
+		ret = device_bind_driver_to_node(dev, "axp_sysreset", "axp_sysreset",
+						 dev_ofnode(dev), NULL);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static const struct udevice_id axp_pmic_ids[] = {
 	{ .compatible = "x-powers,axp152" },
 	{ .compatible = "x-powers,axp202" },
@@ -33,6 +80,6 @@ U_BOOT_DRIVER(axp_pmic) = {
 	.name		= "axp_pmic",
 	.id		= UCLASS_PMIC,
 	.of_match	= axp_pmic_ids,
-	.bind		= dm_scan_fdt_dev,
+	.bind		= axp_pmic_bind,
 	.ops		= &axp_pmic_ops,
 };
-- 
2.39.5