[PATCH v1 4/9] sysreset: implement MAX9807 sysreset functions

[Svyatoslav Ryhel]

MAX8907 PMIC has embedded poweroff function used by some device to initiane
device power off. Implement it as optional sysreset driver guarded by
kconfig option and system-power-controller device tree property.

Tested-by: Ion Agorria <ion at agorria.com>
Signed-off-by: Svyatoslav Ryhel <clamor95 at gmail.com>
---
 drivers/power/pmic/max8907.c        | 14 ++++++++++-
 drivers/sysreset/Kconfig            |  7 ++++++
 drivers/sysreset/Makefile           |  1 +
 drivers/sysreset/sysreset_max8907.c | 37 +++++++++++++++++++++++++++++
 include/power/max8907.h             |  4 ++++
 5 files changed, 62 insertions(+), 1 deletion(-)
 create mode 100644 drivers/sysreset/sysreset_max8907.c

diff --git a/drivers/power/pmic/max8907.c b/drivers/power/pmic/max8907.c
index 5d35957bf40..a7ef70177de 100644
--- a/drivers/power/pmic/max8907.c
+++ b/drivers/power/pmic/max8907.c
@@ -45,7 +45,19 @@ static int max8907_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
 static int max8907_bind(struct udevice *dev)
 {
 	ofnode regulators_node;
-	int children;
+	int children, ret;
+
+	if (IS_ENABLED(CONFIG_SYSRESET_MAX8907) &&
+	    dev_read_bool(dev, "maxim,system-power-controller")) {
+		ret = device_bind_driver_to_node(dev, MAX8907_RST_DRIVER,
+						 "sysreset", dev_ofnode(dev),
+						 NULL);
+		if (ret) {
+			log_debug("%s: cannot bind SYSRESET (ret = %d)\n",
+				  __func__, ret);
+			return ret;
+		}
+	}
 
 	regulators_node = dev_read_subnode(dev, "regulators");
 	if (!ofnode_valid(regulators_node)) {
diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig
index 4972905482a..aa83073c96a 100644
--- a/drivers/sysreset/Kconfig
+++ b/drivers/sysreset/Kconfig
@@ -131,6 +131,13 @@ config SYSRESET_MAX77663
 	help
 	  Enable system power management functions found in MAX77663 PMIC.
 
+config SYSRESET_MAX8907
+	bool "Enable support for MAX8907 PMIC System Reset"
+	depends on DM_PMIC_MAX8907
+	select SYSRESET_CMD_POWEROFF if CMD_POWEROFF
+	help
+	  Enable system power management functions found in MAX8907 PMIC.
+
 config SYSRESET_MICROBLAZE
 	bool "Enable support for Microblaze soft reset"
 	depends on MICROBLAZE
diff --git a/drivers/sysreset/Makefile b/drivers/sysreset/Makefile
index ded91a4d325..f5c78b25896 100644
--- a/drivers/sysreset/Makefile
+++ b/drivers/sysreset/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_SYSRESET_CV1800B) += sysreset_cv1800b.o
 obj-$(CONFIG_$(PHASE_)POWEROFF_GPIO) += poweroff_gpio.o
 obj-$(CONFIG_$(PHASE_)SYSRESET_GPIO) += sysreset_gpio.o
 obj-$(CONFIG_$(PHASE_)SYSRESET_MAX77663) += sysreset_max77663.o
+obj-$(CONFIG_$(PHASE_)SYSRESET_MAX8907) += sysreset_max8907.o
 obj-$(CONFIG_SYSRESET_MPC83XX) += sysreset_mpc83xx.o
 obj-$(CONFIG_SYSRESET_MICROBLAZE) += sysreset_microblaze.o
 obj-$(CONFIG_SYSRESET_OCTEON) += sysreset_octeon.o
diff --git a/drivers/sysreset/sysreset_max8907.c b/drivers/sysreset/sysreset_max8907.c
new file mode 100644
index 00000000000..6f62af9bffe
--- /dev/null
+++ b/drivers/sysreset/sysreset_max8907.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Copyright(C) 2024 Svyatoslav Ryhel <clamor95 at gmail.com>
+ */
+
+#include <dm.h>
+#include <i2c.h>
+#include <errno.h>
+#include <sysreset.h>
+#include <power/pmic.h>
+#include <power/max8907.h>
+
+static int max8907_sysreset_request(struct udevice *dev, enum sysreset_t type)
+{
+	switch (type) {
+	case SYSRESET_POWER:
+	case SYSRESET_POWER_OFF:
+		/* MAX8907: PWR_OFF > RESET_CNFG */
+		pmic_clrsetbits(dev->parent, MAX8907_REG_RESET_CNFG,
+				MASK_POWER_OFF, MASK_POWER_OFF);
+		break;
+	default:
+		return -EPROTONOSUPPORT;
+	}
+
+	return -EINPROGRESS;
+}
+
+static struct sysreset_ops max8907_sysreset = {
+	.request = max8907_sysreset_request,
+};
+
+U_BOOT_DRIVER(sysreset_max8907) = {
+	.id	= UCLASS_SYSRESET,
+	.name	= MAX8907_RST_DRIVER,
+	.ops	= &max8907_sysreset,
+};
diff --git a/include/power/max8907.h b/include/power/max8907.h
index a19b25f44c0..a6e558e582c 100644
--- a/include/power/max8907.h
+++ b/include/power/max8907.h
@@ -12,6 +12,7 @@
 /* Drivers name */
 #define MAX8907_LDO_DRIVER		"max8907_ldo"
 #define MAX8907_SD_DRIVER		"max8907_sd"
+#define MAX8907_RST_DRIVER		"max8907_rst"
 
 /* MAX8907 register map */
 #define MAX8907_REG_SDCTL1		0x04
@@ -39,6 +40,9 @@
 #define MAX8907_REG_LDOCTL18		0x72
 #define MAX8907_REG_LDOCTL20		0x9C
 
+#define MAX8907_REG_RESET_CNFG		0x0F
+#define   MASK_POWER_OFF		BIT(6)
+
 /* MAX8907 configuration values */
 #define MAX8907_CTL			0
 #define MAX8907_SEQCNT			1
-- 
2.43.0