usb: typec: tipd: Switch CD321X power state to S0

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.

Suggested-by: Stan Skowronek <stan@corellium.com>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Sven Peter <sven@svenpeter.dev>
Link: https://lore.kernel.org/r/20210928155502.71372-6-sven@svenpeter.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
index cc4a154eabcb152e6bf0f21fbbf396cd85a60dfa..c74fc9ae1686cf1d28535ae1c30fc450d07d665b 100644 (file)
--- 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 e13b164198433aee72e1fb8e6ffbc96ec83484f3..3dae84c524fb57ce7e8bf2a3a8593a614ad89ca5 100644 (file)
--- 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))