[PATCH v3 5/6] usb: typec: tipd: Switch CD321X power state to S0

From: Sven Peter
Date: Tue Sep 28 2021 - 11:55:40 EST


The Apple CD321x comes up in a low-power state after boot. Usually, the
bootloader will already power it up to S0 but let's do it here as well
in case that didn't happen.

Reviewed-by: Alyssa Rosenzweig <alyssa@xxxxxxxxxxxxx>
Suggested-by: Stan Skowronek <stan@xxxxxxxxxxxxx>
Signed-off-by: Sven Peter <sven@xxxxxxxxxxxxx>
---
no changes since v2

changes since v1:
- dropped the supports_spss flag and only call this for the Apple chip
- added Alyssa's r-b

drivers/usb/typec/tipd/core.c | 37 +++++++++++++++++++++++++++++++
drivers/usb/typec/tipd/tps6598x.h | 6 +++++
2 files changed, 43 insertions(+)

diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
index cc4a154eabcb..c74fc9ae1686 100644
--- a/drivers/usb/typec/tipd/core.c
+++ b/drivers/usb/typec/tipd/core.c
@@ -30,6 +30,7 @@
#define TPS_REG_INT_MASK2 0x17
#define TPS_REG_INT_CLEAR1 0x18
#define TPS_REG_INT_CLEAR2 0x19
+#define TPS_REG_SYSTEM_POWER_STATE 0x20
#define TPS_REG_STATUS 0x1a
#define TPS_REG_SYSTEM_CONF 0x28
#define TPS_REG_CTRL_CONF 0x29
@@ -152,6 +153,11 @@ static int tps6598x_block_write(struct tps6598x *tps, u8 reg,
return regmap_raw_write(tps->regmap, reg, data, len + 1);
}

+static inline int tps6598x_read8(struct tps6598x *tps, u8 reg, u8 *val)
+{
+ return tps6598x_block_read(tps, reg, val, sizeof(u8));
+}
+
static inline int tps6598x_read16(struct tps6598x *tps, u8 reg, u16 *val)
{
return tps6598x_block_read(tps, reg, val, sizeof(u16));
@@ -635,6 +641,32 @@ static int tps6598x_psy_get_prop(struct power_supply *psy,
return ret;
}

+static int cd321x_switch_power_state(struct tps6598x *tps, u8 target_state)
+{
+ u8 state;
+ int ret;
+
+ ret = tps6598x_read8(tps, TPS_REG_SYSTEM_POWER_STATE, &state);
+ if (ret)
+ return ret;
+
+ if (state == target_state)
+ return 0;
+
+ ret = tps6598x_exec_cmd(tps, "SPSS", sizeof(u8), &target_state, 0, NULL);
+ if (ret)
+ return ret;
+
+ ret = tps6598x_read8(tps, TPS_REG_SYSTEM_POWER_STATE, &state);
+ if (ret)
+ return ret;
+
+ if (state != target_state)
+ return -EINVAL;
+
+ return 0;
+}
+
static int devm_tps6598_psy_register(struct tps6598x *tps)
{
struct power_supply_config psy_cfg = {};
@@ -707,6 +739,11 @@ static int tps6598x_probe(struct i2c_client *client)
return ret;

if (np && of_device_is_compatible(np, "apple,cd321x")) {
+ /* Switch CD321X chips to the correct system power state */
+ ret = cd321x_switch_power_state(tps, TPS_SYSTEM_POWER_STATE_S0);
+ if (ret)
+ return ret;
+
/* CD321X chips have all interrupts masked initially */
ret = tps6598x_write64(tps, TPS_REG_INT_MASK1,
APPLE_CD_REG_INT_POWER_STATUS_UPDATE |
diff --git a/drivers/usb/typec/tipd/tps6598x.h b/drivers/usb/typec/tipd/tps6598x.h
index e13b16419843..3dae84c524fb 100644
--- a/drivers/usb/typec/tipd/tps6598x.h
+++ b/drivers/usb/typec/tipd/tps6598x.h
@@ -135,6 +135,12 @@
#define APPLE_CD_REG_INT_STATUS_UPDATE BIT(8)
#define APPLE_CD_REG_INT_PLUG_EVENT BIT(1)

+/* TPS_REG_SYSTEM_POWER_STATE states */
+#define TPS_SYSTEM_POWER_STATE_S0 0x00
+#define TPS_SYSTEM_POWER_STATE_S3 0x03
+#define TPS_SYSTEM_POWER_STATE_S4 0x04
+#define TPS_SYSTEM_POWER_STATE_S5 0x05
+
/* TPS_REG_POWER_STATUS bits */
#define TPS_POWER_STATUS_CONNECTION(x) TPS_FIELD_GET(BIT(0), (x))
#define TPS_POWER_STATUS_SOURCESINK(x) TPS_FIELD_GET(BIT(1), (x))
--
2.25.1