PCA9450 PMIC supports reading the reset status from the PWRON_STAT register. Bits 7-4 give indication of the PMIC reset cause:
- PWRON (BIT7) - Power ON triggered by PMIC_ON_REQ input line, - WDOGB (BIT6) - Boot after cold reset by WDOGB pin (watchdog reset), - SW_RST (BIT5) - Boot after cold reset initiated by the software, - PMIC_RST (BIT4) - Boot after PMIC_RST_B input line trigger. Add support for reading reset status via the sysreset framework in a convenient printable format. Signed-off-by: Primoz Fiser <primoz.fi...@norik.com> --- Change in v2: - new patch as suggested by Paul Geurts Link to v1: https://lore.kernel.org/all/20250716114547.1343797-1-primoz.fi...@norik.com/ drivers/power/pmic/pca9450.c | 38 ++++++++++++++++++++++++++++++++++++ include/power/pca9450.h | 5 +++++ 2 files changed, 43 insertions(+) diff --git a/drivers/power/pmic/pca9450.c b/drivers/power/pmic/pca9450.c index abc39d0a1946..24426df1a49f 100644 --- a/drivers/power/pmic/pca9450.c +++ b/drivers/power/pmic/pca9450.c @@ -166,8 +166,46 @@ static int pca9450_sysreset_request(struct udevice *dev, enum sysreset_t type) return -EINPROGRESS; } +int pca9450_sysreset_get_status(struct udevice *dev, char *buf, int size) +{ + const char *reason; + int ret; + u8 reg; + + ret = pmic_read(dev->parent, PCA9450_PWRON_STAT, ®, 1); + if (ret) + return ret; + + switch (reg) { + case PCA9450_PWRON_STAT_PWRON_MASK: + reason = "PWRON"; + break; + case PCA9450_PWRON_STAT_WDOG_MASK: + reason = "WDOGB"; + break; + case PCA9450_PWRON_STAT_SW_RST_MASK: + reason = "SW_RST"; + break; + case PCA9450_PWRON_STAT_PMIC_RST_MASK: + reason = "PMIC_RST"; + break; + default: + reason = "UNKNOWN"; + break; + } + + ret = snprintf(buf, size, "Reset Status: %s\n", reason); + if (ret < 0) { + dev_err(dev, "Write reset status error (err = %d)\n", ret); + return -EIO; + } + + return 0; +} + static struct sysreset_ops pca9450_sysreset_ops = { .request = pca9450_sysreset_request, + .get_status = pca9450_sysreset_get_status, }; U_BOOT_DRIVER(pca9450_sysreset) = { diff --git a/include/power/pca9450.h b/include/power/pca9450.h index 9119ef793b1f..41b7f95c0340 100644 --- a/include/power/pca9450.h +++ b/include/power/pca9450.h @@ -75,6 +75,11 @@ enum { #define PCA9450_PMIC_RESET_WDOG_B_CFG_WARM 0x40 #define PCA9450_PMIC_RESET_WDOG_B_CFG_COLD_LDO12 0x80 +#define PCA9450_PWRON_STAT_PWRON_MASK 0x80 +#define PCA9450_PWRON_STAT_WDOG_MASK 0x40 +#define PCA9450_PWRON_STAT_SW_RST_MASK 0x20 +#define PCA9450_PWRON_STAT_PMIC_RST_MASK 0x10 + #define PCA9450_SW_RST_COLD_RST 0x14 #endif -- 2.34.1
