This is a note to let you know that I've just added the patch titled
regulator: pca9450: Enable system reset on WDOG_B assertion
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
regulator-pca9450-enable-system-reset-on-wdog_b-asse.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 80239285281f0bfea926caaaa9227c2b4d680974
Author: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
Date: Thu Feb 11 11:55:30 2021 +0100
regulator: pca9450: Enable system reset on WDOG_B assertion
[ Upstream commit f7684f5a048febd2a7bc98ee81d6dce52f7268b8 ]
By default the PCA9450 doesn't handle the assertion of the WDOG_B
signal, but this is required to guarantee that things like software
resets triggered by the watchdog work reliably.
As we don't want to rely on the bootloader to enable this, we tell
the PMIC to issue a cold reset in case the WDOG_B signal is
asserted (WDOG_B_CFG = 10), just as the NXP U-Boot code does.
Signed-off-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210211105534.38972-3-frieder.schrempf@xxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/regulator/pca9450-regulator.c b/drivers/regulator/pca9450-regulator.c
index 1bba8fdcb7b7..833d398c6aa2 100644
--- a/drivers/regulator/pca9450-regulator.c
+++ b/drivers/regulator/pca9450-regulator.c
@@ -797,6 +797,14 @@ static int pca9450_i2c_probe(struct i2c_client *i2c,
return ret;
}
+ /* Set reset behavior on assertion of WDOG_B signal */
+ ret = regmap_update_bits(pca9450->regmap, PCA9450_REG_RESET_CTRL,
+ WDOG_B_CFG_MASK, WDOG_B_CFG_COLD_LDO12);
+ if (ret) {
+ dev_err(&i2c->dev, "Failed to set WDOG_B reset behavior\n");
+ return ret;
+ }
+
/*
* The driver uses the LDO5CTRL_H register to control the LDO5 regulator.
* This is only valid if the SD_VSEL input of the PMIC is high. Let's
diff --git a/include/linux/regulator/pca9450.h b/include/linux/regulator/pca9450.h
index 1bbd3014f906..ccdb5320a240 100644
--- a/include/linux/regulator/pca9450.h
+++ b/include/linux/regulator/pca9450.h
@@ -216,4 +216,11 @@ enum {
#define IRQ_THERM_105 0x02
#define IRQ_THERM_125 0x01
+/* PCA9450_REG_RESET_CTRL bits */
+#define WDOG_B_CFG_MASK 0xC0
+#define WDOG_B_CFG_NONE 0x00
+#define WDOG_B_CFG_WARM 0x40
+#define WDOG_B_CFG_COLD_LDO12 0x80
+#define WDOG_B_CFG_COLD 0xC0
+
#endif /* __LINUX_REG_PCA9450_H__ */
