[PATCH 4/5] Input: aw86927 - handle the AW8693X play and boost register layout

[Qianhui Xu]

AW86937 and AW86938 keep the same register map as the AW86927 but move
two bits and invert the stop handshake:

  - auto boost lives in bit 2 of PLAYCFG3 instead of bit 4, and the boost
    mode in PLAYCFG1 is a two-bit field at bit 5 instead of bit 7;
  - the VBAT mode bit taps the battery voltage instead of the software
    tracked value;
  - stopping is a two-step sequence: select PLAY_MODE_STOP in PLAYCFG3 and
    then issue GO in PLAYCFG4, as the dedicated STOP bit does not exist
    for these parts.  A standby timeout after that is a real failure, so
    return it instead of forcing the state machine.

Signed-off-by: Qianhui Xu <xiaqinghuan@xxxxxxxxxxxxxxxx>
---
 drivers/input/misc/aw86927.c | 65 +++++++++++++++++++++++++++---------
 1 file changed, 49 insertions(+), 16 deletions(-)

diff --git a/drivers/input/misc/aw86927.c b/drivers/input/misc/aw86927.c
index 42eb531c7..e8fd880ac 100644
--- a/drivers/input/misc/aw86927.c
+++ b/drivers/input/misc/aw86927.c
@@ -50,6 +50,14 @@
 #define AW86938_PLAYCFG1_BST_VOUT_VREFSET_MASK	GENMASK(4, 0)
 #define AW86938_PLAYCFG1_BST_7000MV		0x09
 
+/*
+ * The AW8693x parts move auto-boost to bit 2 of PLAYCFG3 and stop playback
+ * by selecting the dedicated stop mode and then issuing a GO, unlike the
+ * AW86927 which has an explicit STOP bit in PLAYCFG4.
+ */
+#define AW8693X_PLAYCFG3_AUTO_BST_MASK		BIT(2)
+#define AW8693X_PLAYCFG3_PLAY_MODE_STOP		3
+
 #define AW86927_PLAYCFG2_REG			0x07
 
 #define AW86927_PLAYCFG3_REG			0x08
@@ -291,9 +299,14 @@ static int aw86927_play_mode(struct aw86927_data *haptics, u8 play_mode)
 
 		err = regmap_update_bits(haptics->regmap,
 					 AW86927_PLAYCFG1_REG,
-					 AW86927_PLAYCFG1_BST_MODE_MASK,
+					 haptics->model == AW86927 ?
+					 AW86927_PLAYCFG1_BST_MODE_MASK :
+					 AW86938_PLAYCFG1_BST_MODE_MASK,
+					 haptics->model == AW86927 ?
 					 FIELD_PREP(AW86927_PLAYCFG1_BST_MODE_MASK,
-						    AW86927_PLAYCFG1_BST_MODE_BYPASS));
+						    AW86927_PLAYCFG1_BST_MODE_BYPASS) :
+					 FIELD_PREP(AW86938_PLAYCFG1_BST_MODE_MASK,
+						    AW86938_PLAYCFG1_BST_MODE_BYPASS));
 		if (err)
 			return err;
 
@@ -301,7 +314,8 @@ static int aw86927_play_mode(struct aw86927_data *haptics, u8 play_mode)
 					 AW86927_VBATCTRL_REG,
 					 AW86927_VBATCTRL_VBAT_MODE_MASK,
 					 FIELD_PREP(AW86927_VBATCTRL_VBAT_MODE_MASK,
-						    AW86927_VBATCTRL_VBAT_MODE_SW));
+						    haptics->model == AW86927 ?
+						    AW86927_VBATCTRL_VBAT_MODE_SW : 1));
 		if (err)
 			return err;
 
@@ -313,23 +327,38 @@ static int aw86927_play_mode(struct aw86927_data *haptics, u8 play_mode)
 
 static int aw86927_stop(struct aw86927_data *haptics)
 {
+	bool aw8693x = haptics->model != AW86927;
 	int err;
 
-	err = regmap_write(haptics->regmap, AW86927_PLAYCFG4_REG, AW86927_PLAYCFG4_STOP);
+	if (aw8693x) {
+		err = regmap_update_bits(haptics->regmap, AW86927_PLAYCFG3_REG,
+					 AW86927_PLAYCFG3_PLAY_MODE_MASK,
+					 AW8693X_PLAYCFG3_PLAY_MODE_STOP);
+		if (err)
+			return err;
+	}
+
+	err = regmap_write(haptics->regmap, AW86927_PLAYCFG4_REG,
+			   aw8693x ? AW86927_PLAYCFG4_GO : AW86927_PLAYCFG4_STOP);
 	if (err) {
 		dev_err(haptics->dev, "Failed to stop playback: %d\n", err);
 		return err;
 	}
 
 	err = aw86927_wait_enter_standby(haptics);
-	if (err) {
-		dev_err(haptics->dev, "Failed to enter standby, trying to force it\n");
-		err = aw86927_play_mode(haptics, AW86927_STANDBY_MODE);
-		if (err)
-			return err;
-	}
+	if (!err)
+		return 0;
 
-	return 0;
+	/*
+	 * The AW8693x reliably reaches standby through the stop mode above, so a
+	 * timeout there is fatal; the AW86927 sometimes needs the nudge.
+	 */
+	if (aw8693x)
+		return err;
+
+	dev_err(haptics->dev, "Failed to enter standby, trying to force it\n");
+
+	return aw86927_play_mode(haptics, AW86927_STANDBY_MODE);
 }
 
 static int aw86927_haptics_play(struct input_dev *dev, void *data, struct ff_effect *effect)
@@ -365,9 +394,13 @@ static int aw86927_play_sine(struct aw86927_data *haptics)
 		return err;
 
 	err = regmap_update_bits(haptics->regmap, AW86927_PLAYCFG3_REG,
-				 AW86927_PLAYCFG3_AUTO_BST_MASK,
+				 haptics->model == AW86927 ?
+				 AW86927_PLAYCFG3_AUTO_BST_MASK :
+				 AW8693X_PLAYCFG3_AUTO_BST_MASK,
+				 haptics->model == AW86927 ?
 				 FIELD_PREP(AW86927_PLAYCFG3_AUTO_BST_MASK,
-					    AW86927_PLAYCFG3_AUTO_BST_ENABLE));
+					    AW86927_PLAYCFG3_AUTO_BST_ENABLE) :
+				 AW8693X_PLAYCFG3_AUTO_BST_MASK);
 	if (err)
 		return err;
 
@@ -605,9 +638,9 @@ static int aw86927_haptic_init(struct aw86927_data *haptics)
 
 	err = regmap_update_bits(haptics->regmap,
 				 AW86927_PLAYCFG3_REG,
-				 AW86927_PLAYCFG3_AUTO_BST_MASK,
-				 FIELD_PREP(AW86927_PLAYCFG3_AUTO_BST_MASK,
-					    AW86927_PLAYCFG3_AUTO_BST_DISABLE));
+				 haptics->model == AW86927 ?
+				 AW86927_PLAYCFG3_AUTO_BST_MASK :
+				 AW8693X_PLAYCFG3_AUTO_BST_MASK, 0);
 	if (err)
 		return err;
 
-- 
2.53.0