Add support for the I2C-connected Awinic AW86938 LRA haptic driver.

The AW86938 has a similar but slightly different register layout. In
particular, the boost mode register values.
The AW86938 also has some extra features that aren't implemented
in this driver yet.

Signed-off-by: Griffin Kroah-Hartman <griffin.kroah@fairphone.com>
---
 drivers/input/misc/aw86927.c | 52 +++++++++++++++++++++++++++++++++++++-------
 1 file changed, 44 insertions(+), 8 deletions(-)

diff --git a/drivers/input/misc/aw86927.c b/drivers/input/misc/aw86927.c
index 7f8cadda7c456d7b5448d1e23edf6e3f2918ba32..e59b958fac1a1144307cb216560f522485ad26e9 100644
--- a/drivers/input/misc/aw86927.c
+++ b/drivers/input/misc/aw86927.c
@@ -43,6 +43,12 @@
 #define AW86927_PLAYCFG1_BST_VOUT_VREFSET_MASK	GENMASK(6, 0)
 #define AW86927_PLAYCFG1_BST_8500MV		0x50
 
+#define AW86938_PLAYCFG1_REG			0x06
+#define AW86938_PLAYCFG1_BST_MODE_MASK		GENMASK(5, 5)
+#define AW86938_PLAYCFG1_BST_MODE_BYPASS	0
+#define AW86938_PLAYCFG1_BST_VOUT_VREFSET_MASK	GENMASK(4, 0)
+#define AW86938_PLAYCFG1_BST_7000MV		0x11
+
 #define AW86927_PLAYCFG2_REG			0x07
 
 #define AW86927_PLAYCFG3_REG			0x08
@@ -140,6 +146,7 @@
 #define AW86927_CHIPIDH_REG			0x57
 #define AW86927_CHIPIDL_REG			0x58
 #define AW86927_CHIPID				0x9270
+#define AW86938_CHIPID				0x9380
 
 #define AW86927_TMCFG_REG			0x5b
 #define AW86927_TMCFG_UNLOCK			0x7d
@@ -173,7 +180,13 @@ enum aw86927_work_mode {
 	AW86927_RAM_MODE,
 };
 
+enum aw86927_model {
+	AW86927,
+	AW86938,
+};
+
 struct aw86927_data {
+	enum aw86927_model model;
 	struct work_struct play_work;
 	struct device *dev;
 	struct input_dev *input_dev;
@@ -565,13 +578,26 @@ static int aw86927_haptic_init(struct aw86927_data *haptics)
 	if (err)
 		return err;
 
-	err = regmap_update_bits(haptics->regmap,
-				 AW86927_PLAYCFG1_REG,
-				 AW86927_PLAYCFG1_BST_VOUT_VREFSET_MASK,
-				 FIELD_PREP(AW86927_PLAYCFG1_BST_VOUT_VREFSET_MASK,
-					    AW86927_PLAYCFG1_BST_8500MV));
-	if (err)
-		return err;
+	switch (haptics->model) {
+	case AW86927:
+		err = regmap_update_bits(haptics->regmap,
+				AW86927_PLAYCFG1_REG,
+				AW86927_PLAYCFG1_BST_VOUT_VREFSET_MASK,
+				FIELD_PREP(AW86927_PLAYCFG1_BST_VOUT_VREFSET_MASK,
+					AW86927_PLAYCFG1_BST_8500MV));
+		if (err)
+			return err;
+		break;
+	case AW86938:
+		err = regmap_update_bits(haptics->regmap,
+				AW86938_PLAYCFG1_REG,
+				AW86938_PLAYCFG1_BST_VOUT_VREFSET_MASK,
+				FIELD_PREP(AW86938_PLAYCFG1_BST_VOUT_VREFSET_MASK,
+					AW86938_PLAYCFG1_BST_7000MV));
+		if (err)
+			return err;
+		break;
+	}
 
 	err = regmap_update_bits(haptics->regmap,
 				 AW86927_PLAYCFG3_REG,
@@ -599,6 +625,9 @@ static int aw86927_ram_init(struct aw86927_data *haptics)
 				 FIELD_PREP(AW86927_SYSCTRL3_EN_RAMINIT_MASK,
 					    AW86927_SYSCTRL3_EN_RAMINIT_ON));
 
+	/* AW86938 wants a 1ms delay here */
+	usleep_range(1000, 1500);
+
 	/* Set base address for the start of the SRAM waveforms */
 	err = regmap_write(haptics->regmap,
 			   AW86927_BASEADDRH_REG, AW86927_BASEADDRH_VAL);
@@ -717,7 +746,14 @@ static int aw86927_detect(struct aw86927_data *haptics)
 
 	chip_id = be16_to_cpu(read_buf);
 
-	if (chip_id != AW86927_CHIPID) {
+	switch (chip_id) {
+	case AW86927_CHIPID:
+		haptics->model = AW86927;
+		break;
+	case AW86938_CHIPID:
+		haptics->model = AW86938;
+		break;
+	default:
 		dev_err(haptics->dev, "Unexpected CHIPID value 0x%x\n", chip_id);
 		return -ENODEV;
 	}

-- 
2.43.0

On Mon, Mar 02, 2026 at 11:50:27AM +0100, Griffin Kroah-Hartman wrote:
> Add support for the I2C-connected Awinic AW86938 LRA haptic driver.
> 
> The AW86938 has a similar but slightly different register layout. In
> particular, the boost mode register values.
> The AW86938 also has some extra features that aren't implemented
> in this driver yet.
> 
> Signed-off-by: Griffin Kroah-Hartman <griffin.kroah@fairphone.com>

Applied, thank you.

-- 
Dmitry

Hi Dmitry,

On Wed Mar 4, 2026 at 5:56 AM CET, Dmitry Torokhov wrote:
> On Mon, Mar 02, 2026 at 11:50:27AM +0100, Griffin Kroah-Hartman wrote:
>> Add support for the I2C-connected Awinic AW86938 LRA haptic driver.
>> 
>> The AW86938 has a similar but slightly different register layout. In
>> particular, the boost mode register values.
>> The AW86938 also has some extra features that aren't implemented
>> in this driver yet.
>> 
>> Signed-off-by: Griffin Kroah-Hartman <griffin.kroah@fairphone.com>
>
> Applied, thank you.

I'm curious, where did you apply these patches? linux-next doesn't have
it and I don't see it in your kernel.org repo either.
https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git/

Did this slip through the cracks or will these patches still appear
there?

Regards
Luca

On Wed, Apr 01, 2026 at 04:44:47PM +0200, Luca Weiss wrote:
> Hi Dmitry,
> 
> On Wed Mar 4, 2026 at 5:56 AM CET, Dmitry Torokhov wrote:
> > On Mon, Mar 02, 2026 at 11:50:27AM +0100, Griffin Kroah-Hartman wrote:
> >> Add support for the I2C-connected Awinic AW86938 LRA haptic driver.
> >> 
> >> The AW86938 has a similar but slightly different register layout. In
> >> particular, the boost mode register values.
> >> The AW86938 also has some extra features that aren't implemented
> >> in this driver yet.
> >> 
> >> Signed-off-by: Griffin Kroah-Hartman <griffin.kroah@fairphone.com>
> >
> > Applied, thank you.
> 
> I'm curious, where did you apply these patches? linux-next doesn't have
> it and I don't see it in your kernel.org repo either.
> https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git/
> 
> Did this slip through the cracks or will these patches still appear
> there?

My bad, I think there was a conflict with Dan Carpenter's patch and as a
result the series got stuck in my internal queue. My apologies.

Should be out in 'next' branch now.

Thanks.

-- 
Dmitry