sysreset: implement MAX9807 sysreset functions

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 <[email protected]>
Signed-off-by: Svyatoslav Ryhel <[email protected]>

5 files changed, 62 insertions, 1 deletions

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 <[email protected]>
+ */
+
+#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