ARK-OS/arkos/kernel/drivers/input/misc/aw86927.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2025 Griffin Kroah-Hartman <griffin.kroah@fairphone.com>
 *
 * Partially based on vendor driver:
 *	Copyright (c) 2021 AWINIC Technology CO., LTD
 *
 */

#include <linux/bitfield.h>
#include <linux/bits.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/types.h>

#define AW86927_RSTCFG_REG			0x00
#define AW86927_RSTCFG_SOFTRST			0xaa

#define AW86927_SYSINT_REG			0x02
#define AW86927_SYSINT_BST_SCPI			BIT(7)
#define AW86927_SYSINT_BST_OVPI			BIT(6)
#define AW86927_SYSINT_UVLI			BIT(5)
#define AW86927_SYSINT_FF_AEI			BIT(4)
#define AW86927_SYSINT_FF_AFI			BIT(3)
#define AW86927_SYSINT_OCDI			BIT(2)
#define AW86927_SYSINT_OTI			BIT(1)
#define AW86927_SYSINT_DONEI			BIT(0)

#define AW86927_SYSINTM_REG			0x03
#define AW86927_SYSINTM_BST_OVPM		BIT(6)
#define AW86927_SYSINTM_FF_AEM			BIT(4)
#define AW86927_SYSINTM_FF_AFM			BIT(3)
#define AW86927_SYSINTM_DONEM			BIT(0)

#define AW86927_PLAYCFG1_REG			0x06
#define AW86927_PLAYCFG1_BST_MODE_MASK		GENMASK(7, 7)
#define AW86927_PLAYCFG1_BST_MODE_BYPASS	0
#define AW86927_PLAYCFG1_BST_VOUT_VREFSET_MASK	GENMASK(6, 0)
#define AW86927_PLAYCFG1_BST_8500MV		0x50

#define AW86927_PLAYCFG2_REG			0x07

#define AW86927_PLAYCFG3_REG			0x08
#define AW86927_PLAYCFG3_AUTO_BST_MASK		GENMASK(4, 4)
#define AW86927_PLAYCFG3_AUTO_BST_ENABLE	1
#define AW86927_PLAYCFG3_AUTO_BST_DISABLE	0
#define AW86927_PLAYCFG3_PLAY_MODE_MASK		GENMASK(1, 0)
#define AW86927_PLAYCFG3_PLAY_MODE_RAM		0

#define AW86927_PLAYCFG4_REG			0x09
#define AW86927_PLAYCFG4_STOP			BIT(1)
#define AW86927_PLAYCFG4_GO			BIT(0)

#define AW86927_WAVCFG1_REG			0x0a
#define AW86927_WAVCFG1_WAVSEQ1_MASK		GENMASK(6, 0)

#define AW86927_WAVCFG2_REG			0x0b
#define AW86927_WAVCFG2_WAVSEQ2_MASK		GENMASK(6, 0)

#define AW86927_WAVCFG9_REG			0x12
#define AW86927_WAVCFG9_SEQ1LOOP_MASK		GENMASK(7, 4)
#define AW86927_WAVCFG9_SEQ1LOOP_INFINITELY	0x0f

#define AW86927_CONTCFG1_REG			0x18
#define AW86927_CONTCFG1_BRK_BST_MD_MASK	GENMASK(6, 6)

#define AW86927_CONTCFG5_REG			0x1c
#define AW86927_CONTCFG5_BST_BRK_GAIN_MASK	GENMASK(7, 4)
#define AW86927_CONTCFG5_BRK_GAIN_MASK		GENMASK(3, 0)

#define AW86927_CONTCFG10_REG			0x21
#define AW86927_CONTCFG10_BRK_TIME_MASK		GENMASK(7, 0)
#define AW86927_CONTCFG10_BRK_TIME_DEFAULT	8

#define AW86927_CONTCFG13_REG			0x24
#define AW86927_CONTCFG13_TSET_MASK		GENMASK(7, 4)
#define AW86927_CONTCFG13_BEME_SET_MASK		GENMASK(3, 0)

#define AW86927_BASEADDRH_REG			0x2d
#define AW86927_BASEADDRL_REG			0x2e

#define AW86927_GLBRD5_REG			0x3f
#define AW86927_GLBRD5_STATE_MASK		GENMASK(3, 0)
#define AW86927_GLBRD5_STATE_STANDBY		0

#define AW86927_RAMADDRH_REG			0x40

#define AW86927_RAMADDRL_REG			0x41

#define AW86927_RAMDATA_REG			0x42

#define AW86927_SYSCTRL3_REG			0x45
#define AW86927_SYSCTRL3_STANDBY_MASK           GENMASK(5, 5)
#define AW86927_SYSCTRL3_STANDBY_ON             1
#define AW86927_SYSCTRL3_STANDBY_OFF            0
#define AW86927_SYSCTRL3_EN_RAMINIT_MASK        GENMASK(2, 2)
#define AW86927_SYSCTRL3_EN_RAMINIT_ON          1
#define AW86927_SYSCTRL3_EN_RAMINIT_OFF         0

#define AW86927_SYSCTRL4_REG			0x46
#define AW86927_SYSCTRL4_WAVDAT_MODE_MASK	GENMASK(6, 5)
#define AW86927_SYSCTRL4_WAVDAT_24K		0
#define AW86927_SYSCTRL4_INT_EDGE_MODE_MASK	GENMASK(4, 4)
#define AW86927_SYSCTRL4_INT_EDGE_MODE_POS	0
#define AW86927_SYSCTRL4_INT_MODE_MASK		GENMASK(3, 3)
#define AW86927_SYSCTRL4_INT_MODE_EDGE		1
#define AW86927_SYSCTRL4_GAIN_BYPASS_MASK	GENMASK(0, 0)

#define AW86927_PWMCFG1_REG			0x48
#define AW86927_PWMCFG1_PRC_EN_MASK		GENMASK(7, 7)
#define AW86927_PWMCFG1_PRC_DISABLE		0

#define AW86927_PWMCFG3_REG			0x4a
#define AW86927_PWMCFG3_PR_EN_MASK		GENMASK(7, 7)
#define AW86927_PWMCFG3_PRCTIME_MASK		GENMASK(6, 0)

#define AW86927_PWMCFG4_REG			0x4b
#define AW86927_PWMCFG4_PRTIME_MASK		GENMASK(7, 0)

#define AW86927_VBATCTRL_REG			0x4c
#define AW86927_VBATCTRL_VBAT_MODE_MASK		GENMASK(6, 6)
#define AW86927_VBATCTRL_VBAT_MODE_SW		0

#define AW86927_DETCFG1_REG			0x4d
#define AW86927_DETCFG1_DET_GO_MASK		GENMASK(1, 0)
#define AW86927_DETCFG1_DET_GO_DET_SEQ0		1
#define AW86927_DETCFG1_DET_GO_NA		0

#define AW86927_DETCFG2_REG			0x4e
#define AW86927_DETCFG2_DET_SEQ0_MASK		GENMASK(6, 3)
#define AW86927_DETCFG2_DET_SEQ0_VBAT		0
#define AW86927_DETCFG2_D2S_GAIN_MASK		GENMASK(2, 0)
#define AW86927_DETCFG2_D2S_GAIN_10		4

#define AW86927_CHIPIDH_REG			0x57
#define AW86927_CHIPIDL_REG			0x58
#define AW86927_CHIPID				0x9270

#define AW86927_TMCFG_REG			0x5b
#define AW86927_TMCFG_UNLOCK			0x7d
#define AW86927_TMCFG_LOCK			0x00

#define AW86927_ANACFG11_REG			0x70

#define AW86927_ANACFG12_REG			0x71
#define AW86927_ANACFG12_BST_SKIP_MASK		GENMASK(7, 7)
#define AW86927_ANACFG12_BST_SKIP_SHUTDOWN	1

#define AW86927_ANACFG13_REG			0x72
#define AW86927_ANACFG13_BST_PC_MASK		GENMASK(7, 4)
#define AW86927_ANACFG13_BST_PEAKCUR_3P45A	6

#define AW86927_ANACFG15_REG			0x74
#define AW86927_ANACFG15_BST_PEAK_MODE_MASK	GENMASK(7, 7)
#define AW86927_ANACFG15_BST_PEAK_BACK		1

#define AW86927_ANACFG16_REG			0x75
#define AW86927_ANACFG16_BST_SRC_MASK		GENMASK(4, 4)
#define AW86927_ANACFG16_BST_SRC_3NS		0

/* default value of base addr */
#define AW86927_RAM_BASE_ADDR			0x800
#define AW86927_BASEADDRH_VAL			0x08
#define AW86927_BASEADDRL_VAL			0x00

enum aw86927_work_mode {
	AW86927_STANDBY_MODE,
	AW86927_RAM_MODE,
};

struct aw86927_data {
	struct work_struct play_work;
	struct device *dev;
	struct input_dev *input_dev;
	struct i2c_client *client;
	struct regmap *regmap;
	struct gpio_desc *reset_gpio;
	bool running;
};

static const struct regmap_config aw86927_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.cache_type = REGCACHE_NONE,
	.max_register = 0x80,
};

/*
 * Sine wave representing the magnitude of the drive to be used.
 * Data is encoded in two's complement.
 *   round(84 * sin(x / 16.25))
 */
static const u8 aw86927_waveform[] = {
	0x00, 0x05, 0x0a, 0x0f, 0x14, 0x1a, 0x1f, 0x23, 0x28, 0x2d, 0x31, 0x35,
	0x39, 0x3d, 0x41, 0x44, 0x47, 0x4a, 0x4c, 0x4f, 0x51, 0x52, 0x53, 0x54,
	0x55, 0x55, 0x55, 0x55, 0x55, 0x54, 0x52, 0x51, 0x4f, 0x4d, 0x4a, 0x47,
	0x44, 0x41, 0x3d, 0x3a, 0x36, 0x31, 0x2d, 0x28, 0x24, 0x1f, 0x1a, 0x15,
	0x10, 0x0a, 0x05, 0x00, 0xfc, 0xf6, 0xf1, 0xec, 0xe7, 0xe2, 0xdd, 0xd8,
	0xd4, 0xcf, 0xcb, 0xc7, 0xc3, 0xbf, 0xbc, 0xb9, 0xb6, 0xb4, 0xb1, 0xb0,
	0xae, 0xad, 0xac, 0xab, 0xab, 0xab, 0xab, 0xab, 0xac, 0xae, 0xaf, 0xb1,
	0xb3, 0xb6, 0xb8, 0xbc, 0xbf, 0xc2, 0xc6, 0xca, 0xce, 0xd3, 0xd7, 0xdc,
	0xe1, 0xe6, 0xeb, 0xf0, 0xf5, 0xfb
};

struct aw86927_sram_waveform_header {
	u8 version;
	__be16 start_address;
	__be16 end_address;
} __packed;

static const struct aw86927_sram_waveform_header sram_waveform_header = {
	.version = 0x01,
	.start_address = cpu_to_be16(AW86927_RAM_BASE_ADDR +
			sizeof(struct aw86927_sram_waveform_header)),
	.end_address = cpu_to_be16(AW86927_RAM_BASE_ADDR +
			sizeof(struct aw86927_sram_waveform_header) +
			ARRAY_SIZE(aw86927_waveform) - 1),
};

static int aw86927_wait_enter_standby(struct aw86927_data *haptics)
{
	unsigned int reg_val;
	int err;

	err = regmap_read_poll_timeout(haptics->regmap, AW86927_GLBRD5_REG, reg_val,
				       (FIELD_GET(AW86927_GLBRD5_STATE_MASK, reg_val) ==
						AW86927_GLBRD5_STATE_STANDBY),
				       2500, 2500 * 100);

	if (err) {
		dev_err(haptics->dev, "did not enter standby: %d\n", err);
		return err;
	}
	return 0;
}

static int aw86927_play_mode(struct aw86927_data *haptics, u8 play_mode)
{
	int err;

	switch (play_mode) {
	case AW86927_STANDBY_MODE:
		/* Briefly toggle standby, then toggle back to standby off */
		err = regmap_update_bits(haptics->regmap,
					 AW86927_SYSCTRL3_REG,
					 AW86927_SYSCTRL3_STANDBY_MASK,
					 FIELD_PREP(AW86927_SYSCTRL3_STANDBY_MASK,
						    AW86927_SYSCTRL3_STANDBY_ON));
		if (err)
			return err;

		err = regmap_update_bits(haptics->regmap,
					 AW86927_SYSCTRL3_REG,
					 AW86927_SYSCTRL3_STANDBY_MASK,
					 FIELD_PREP(AW86927_SYSCTRL3_STANDBY_MASK,
						    AW86927_SYSCTRL3_STANDBY_OFF));
		if (err)
			return err;

		break;

	case AW86927_RAM_MODE:
		err = regmap_update_bits(haptics->regmap,
					 AW86927_PLAYCFG3_REG,
					 AW86927_PLAYCFG3_PLAY_MODE_MASK,
					 FIELD_PREP(AW86927_PLAYCFG3_PLAY_MODE_MASK,
						    AW86927_PLAYCFG3_PLAY_MODE_RAM));
		if (err)
			return err;

		err = regmap_update_bits(haptics->regmap,
					 AW86927_PLAYCFG1_REG,
					 AW86927_PLAYCFG1_BST_MODE_MASK,
					 FIELD_PREP(AW86927_PLAYCFG1_BST_MODE_MASK,
						    AW86927_PLAYCFG1_BST_MODE_BYPASS));
		if (err)
			return err;

		err = regmap_update_bits(haptics->regmap,
					 AW86927_VBATCTRL_REG,
					 AW86927_VBATCTRL_VBAT_MODE_MASK,
					 FIELD_PREP(AW86927_VBATCTRL_VBAT_MODE_MASK,
						    AW86927_VBATCTRL_VBAT_MODE_SW));
		if (err)
			return err;

		break;
	}

	return 0;
}

static int aw86927_stop(struct aw86927_data *haptics)
{
	int err;

	err = regmap_write(haptics->regmap, AW86927_PLAYCFG4_REG, 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;
	}

	return 0;
}

static int aw86927_haptics_play(struct input_dev *dev, void *data, struct ff_effect *effect)
{
	struct aw86927_data *haptics = input_get_drvdata(dev);
	int level;

	level = effect->u.rumble.strong_magnitude;
	if (!level)
		level = effect->u.rumble.weak_magnitude;

	/* If already running, don't restart playback */
	if (haptics->running && level)
		return 0;

	haptics->running = level;
	schedule_work(&haptics->play_work);

	return 0;
}

static int aw86927_play_sine(struct aw86927_data *haptics)
{
	int err;

	err = aw86927_stop(haptics);
	if (err)
		return err;

	err = aw86927_play_mode(haptics, AW86927_RAM_MODE);
	if (err)
		return err;

	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_ENABLE));
	if (err)
		return err;

	/* Set waveseq 1 to the first wave */
	err = regmap_update_bits(haptics->regmap, AW86927_WAVCFG1_REG,
				 AW86927_WAVCFG1_WAVSEQ1_MASK,
				 FIELD_PREP(AW86927_WAVCFG1_WAVSEQ1_MASK, 1));
	if (err)
		return err;

	/* set wavseq 2 to zero */
	err = regmap_update_bits(haptics->regmap, AW86927_WAVCFG2_REG,
				 AW86927_WAVCFG2_WAVSEQ2_MASK,
				 FIELD_PREP(AW86927_WAVCFG2_WAVSEQ2_MASK, 0));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_WAVCFG9_REG,
				 AW86927_WAVCFG9_SEQ1LOOP_MASK,
				 FIELD_PREP(AW86927_WAVCFG9_SEQ1LOOP_MASK,
					    AW86927_WAVCFG9_SEQ1LOOP_INFINITELY));
	if (err)
		return err;

	/* set gain to value lower than 0x80 to avoid distorted playback */
	err = regmap_write(haptics->regmap, AW86927_PLAYCFG2_REG, 0x7c);
	if (err)
		return err;

	/* Start playback */
	err = regmap_write(haptics->regmap, AW86927_PLAYCFG4_REG, AW86927_PLAYCFG4_GO);
	if (err)
		return err;

	return 0;
}

static void aw86927_close(struct input_dev *input)
{
	struct aw86927_data *haptics = input_get_drvdata(input);
	struct device *dev = &haptics->client->dev;
	int err;

	cancel_work_sync(&haptics->play_work);

	err = aw86927_stop(haptics);
	if (err)
		dev_err(dev, "Failed to close the Driver: %d\n", err);
}

static void aw86927_haptics_play_work(struct work_struct *work)
{
	struct aw86927_data *haptics =
		container_of(work, struct aw86927_data, play_work);
	struct device *dev = &haptics->client->dev;
	int err;

	if (haptics->running)
		err = aw86927_play_sine(haptics);
	else
		err = aw86927_stop(haptics);

	if (err)
		dev_err(dev, "Failed to execute work command: %d\n", err);
}

static void aw86927_hw_reset(struct aw86927_data *haptics)
{
	/* Assert reset */
	gpiod_set_value_cansleep(haptics->reset_gpio, 1);
	/* Wait ~1ms */
	usleep_range(1000, 2000);
	/* Deassert reset */
	gpiod_set_value_cansleep(haptics->reset_gpio, 0);
	/* Wait ~8ms until I2C is accessible */
	usleep_range(8000, 8500);
}

static int aw86927_haptic_init(struct aw86927_data *haptics)
{
	int err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_SYSCTRL4_REG,
				 AW86927_SYSCTRL4_WAVDAT_MODE_MASK,
				 FIELD_PREP(AW86927_SYSCTRL4_WAVDAT_MODE_MASK,
					    AW86927_SYSCTRL4_WAVDAT_24K));
	if (err)
		return err;

	/* enable gain bypass */
	err = regmap_update_bits(haptics->regmap,
				 AW86927_SYSCTRL4_REG,
				 AW86927_SYSCTRL4_GAIN_BYPASS_MASK,
				 FIELD_PREP(AW86927_SYSCTRL4_GAIN_BYPASS_MASK,
					    0x01));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_TMCFG_REG, AW86927_TMCFG_UNLOCK);
	if (err)
		return err;

	err = regmap_write(haptics->regmap, AW86927_ANACFG11_REG, 0x0f);
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_ANACFG12_REG,
				 AW86927_ANACFG12_BST_SKIP_MASK,
				 FIELD_PREP(AW86927_ANACFG12_BST_SKIP_MASK,
					    AW86927_ANACFG12_BST_SKIP_SHUTDOWN));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_ANACFG15_REG,
				 AW86927_ANACFG15_BST_PEAK_MODE_MASK,
				 FIELD_PREP(AW86927_ANACFG15_BST_PEAK_MODE_MASK,
					    AW86927_ANACFG15_BST_PEAK_BACK));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_ANACFG16_REG,
				 AW86927_ANACFG16_BST_SRC_MASK,
				 FIELD_PREP(AW86927_ANACFG16_BST_SRC_MASK,
					    AW86927_ANACFG16_BST_SRC_3NS));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_TMCFG_REG, AW86927_TMCFG_LOCK);
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_CONTCFG1_REG,
				 AW86927_CONTCFG1_BRK_BST_MD_MASK,
				 FIELD_PREP(AW86927_CONTCFG1_BRK_BST_MD_MASK, 0x00));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_CONTCFG5_REG,
			   FIELD_PREP(AW86927_CONTCFG5_BST_BRK_GAIN_MASK, 0x05) |
				FIELD_PREP(AW86927_CONTCFG5_BRK_GAIN_MASK, 0x08));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap, AW86927_CONTCFG10_REG,
				 AW86927_CONTCFG10_BRK_TIME_MASK,
				 FIELD_PREP(AW86927_CONTCFG10_BRK_TIME_MASK,
					    AW86927_CONTCFG10_BRK_TIME_DEFAULT));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_CONTCFG13_REG,
			   FIELD_PREP(AW86927_CONTCFG13_TSET_MASK, 0x06) |
				FIELD_PREP(AW86927_CONTCFG13_BEME_SET_MASK, 0x02));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_DETCFG2_REG,
				 AW86927_DETCFG2_D2S_GAIN_MASK,
				 FIELD_PREP(AW86927_DETCFG2_D2S_GAIN_MASK,
					    AW86927_DETCFG2_D2S_GAIN_10));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_PWMCFG1_REG,
				 AW86927_PWMCFG1_PRC_EN_MASK,
				 FIELD_PREP(AW86927_PWMCFG1_PRC_EN_MASK,
					    AW86927_PWMCFG1_PRC_DISABLE));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_PWMCFG3_REG,
			   FIELD_PREP(AW86927_PWMCFG3_PR_EN_MASK, 0x01) |
				FIELD_PREP(AW86927_PWMCFG3_PRCTIME_MASK, 0x3f));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_PWMCFG4_REG,
				 AW86927_PWMCFG4_PRTIME_MASK,
				 FIELD_PREP(AW86927_PWMCFG4_PRTIME_MASK, 0x32));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_TMCFG_REG, AW86927_TMCFG_UNLOCK);
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_ANACFG13_REG,
				 AW86927_ANACFG13_BST_PC_MASK,
				 FIELD_PREP(AW86927_ANACFG13_BST_PC_MASK,
					    AW86927_ANACFG13_BST_PEAKCUR_3P45A));
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_TMCFG_REG, AW86927_TMCFG_LOCK);
	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;

	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));
	if (err)
		return err;

	return 0;
}

static int aw86927_ram_init(struct aw86927_data *haptics)
{
	int err;

	err = aw86927_wait_enter_standby(haptics);
	if (err)
		return err;

	/* Enable SRAM init */
	err = regmap_update_bits(haptics->regmap,
				 AW86927_SYSCTRL3_REG,
				 AW86927_SYSCTRL3_EN_RAMINIT_MASK,
				 FIELD_PREP(AW86927_SYSCTRL3_EN_RAMINIT_MASK,
					    AW86927_SYSCTRL3_EN_RAMINIT_ON));

	/* Set base address for the start of the SRAM waveforms */
	err = regmap_write(haptics->regmap,
			   AW86927_BASEADDRH_REG, AW86927_BASEADDRH_VAL);
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_BASEADDRL_REG, AW86927_BASEADDRL_VAL);
	if (err)
		return err;

	/* Set start of SRAM, before the data is written it will be the same as the base */
	err = regmap_write(haptics->regmap,
			   AW86927_RAMADDRH_REG, AW86927_BASEADDRH_VAL);
	if (err)
		return err;

	err = regmap_write(haptics->regmap,
			   AW86927_RAMADDRL_REG, AW86927_BASEADDRL_VAL);
	if (err)
		return err;

	/* Write waveform header to SRAM */
	err = regmap_noinc_write(haptics->regmap, AW86927_RAMDATA_REG,
				 &sram_waveform_header, sizeof(sram_waveform_header));
	if (err)
		return err;

	/* Write waveform to SRAM */
	err = regmap_noinc_write(haptics->regmap, AW86927_RAMDATA_REG,
				 aw86927_waveform, ARRAY_SIZE(aw86927_waveform));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_DETCFG2_REG,
				 AW86927_DETCFG2_DET_SEQ0_MASK,
				 FIELD_PREP(AW86927_DETCFG2_DET_SEQ0_MASK,
					    AW86927_DETCFG2_DET_SEQ0_VBAT));
	if (err)
		return err;

	err = regmap_update_bits(haptics->regmap,
				 AW86927_DETCFG1_REG,
				 AW86927_DETCFG1_DET_GO_MASK,
				 FIELD_PREP(AW86927_DETCFG1_DET_GO_MASK,
					    AW86927_DETCFG1_DET_GO_DET_SEQ0));
	if (err)
		return err;

	usleep_range(3000, 3500);

	err = regmap_update_bits(haptics->regmap,
				 AW86927_DETCFG1_REG,
				 AW86927_DETCFG1_DET_GO_MASK,
				 FIELD_PREP(AW86927_DETCFG1_DET_GO_MASK,
					    AW86927_DETCFG1_DET_GO_NA));
	if (err)
		return err;

	/* Disable SRAM init */
	err = regmap_update_bits(haptics->regmap,
				 AW86927_SYSCTRL3_REG,
				 AW86927_SYSCTRL3_EN_RAMINIT_MASK,
				 FIELD_PREP(AW86927_SYSCTRL3_EN_RAMINIT_MASK,
					    AW86927_SYSCTRL3_EN_RAMINIT_OFF));
	if (err)
		return err;

	return 0;
}

static irqreturn_t aw86927_irq(int irq, void *data)
{
	struct aw86927_data *haptics = data;
	struct device *dev = &haptics->client->dev;
	unsigned int reg_val;
	int err;

	err = regmap_read(haptics->regmap, AW86927_SYSINT_REG, &reg_val);
	if (err) {
		dev_err(dev, "Failed to read SYSINT register: %d\n", err);
		return IRQ_NONE;
	}

	if (reg_val & AW86927_SYSINT_BST_SCPI)
		dev_err(dev, "Received a Short Circuit Protection interrupt\n");
	if (reg_val & AW86927_SYSINT_BST_OVPI)
		dev_err(dev, "Received an Over Voltage Protection interrupt\n");
	if (reg_val & AW86927_SYSINT_UVLI)
		dev_err(dev, "Received an Under Voltage Lock Out interrupt\n");
	if (reg_val & AW86927_SYSINT_OCDI)
		dev_err(dev, "Received an Over Current interrupt\n");
	if (reg_val & AW86927_SYSINT_OTI)
		dev_err(dev, "Received an Over Temperature interrupt\n");

	if (reg_val & AW86927_SYSINT_DONEI)
		dev_dbg(dev, "Chip playback done!\n");
	if (reg_val & AW86927_SYSINT_FF_AFI)
		dev_dbg(dev, "The RTP mode FIFO is almost full!\n");
	if (reg_val & AW86927_SYSINT_FF_AEI)
		dev_dbg(dev, "The RTP mode FIFO is almost empty!\n");

	return IRQ_HANDLED;
}

static int aw86927_detect(struct aw86927_data *haptics)
{
	__be16 read_buf;
	u16 chip_id;
	int err;

	err = regmap_bulk_read(haptics->regmap, AW86927_CHIPIDH_REG, &read_buf, 2);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to read CHIPID registers\n");

	chip_id = be16_to_cpu(read_buf);

	if (chip_id != AW86927_CHIPID) {
		dev_err(haptics->dev, "Unexpected CHIPID value 0x%x\n", chip_id);
		return -ENODEV;
	}

	return 0;
}

static int aw86927_probe(struct i2c_client *client)
{
	struct aw86927_data *haptics;
	int err;

	haptics = devm_kzalloc(&client->dev, sizeof(struct aw86927_data), GFP_KERNEL);
	if (!haptics)
		return -ENOMEM;

	haptics->dev = &client->dev;
	haptics->client = client;

	i2c_set_clientdata(client, haptics);

	haptics->regmap = devm_regmap_init_i2c(client, &aw86927_regmap_config);
	if (IS_ERR(haptics->regmap))
		return dev_err_probe(haptics->dev, PTR_ERR(haptics->regmap),
					"Failed to allocate register map\n");

	haptics->input_dev = devm_input_allocate_device(haptics->dev);
	if (!haptics->input_dev)
		return -ENOMEM;

	haptics->reset_gpio = devm_gpiod_get(haptics->dev, "reset", GPIOD_OUT_HIGH);
	if (IS_ERR(haptics->reset_gpio))
		return dev_err_probe(haptics->dev, PTR_ERR(haptics->reset_gpio),
				     "Failed to get reset gpio\n");

	/* Hardware reset */
	aw86927_hw_reset(haptics);

	/* Software reset */
	err = regmap_write(haptics->regmap, AW86927_RSTCFG_REG, AW86927_RSTCFG_SOFTRST);
	if (err)
		return dev_err_probe(haptics->dev, err,	"Failed Software reset\n");

	/* Wait ~3ms until I2C is accessible */
	usleep_range(3000, 3500);

	err = aw86927_detect(haptics);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to find chip\n");

	/* IRQ config */
	err = regmap_write(haptics->regmap, AW86927_SYSCTRL4_REG,
			   FIELD_PREP(AW86927_SYSCTRL4_INT_MODE_MASK,
				      AW86927_SYSCTRL4_INT_MODE_EDGE) |
				FIELD_PREP(AW86927_SYSCTRL4_INT_EDGE_MODE_MASK,
					   AW86927_SYSCTRL4_INT_EDGE_MODE_POS));
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to configure interrupt modes\n");

	err = regmap_write(haptics->regmap, AW86927_SYSINTM_REG,
			   AW86927_SYSINTM_BST_OVPM |
				AW86927_SYSINTM_FF_AEM |
				AW86927_SYSINTM_FF_AFM |
				AW86927_SYSINTM_DONEM);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to configure interrupt masks\n");

	err = devm_request_threaded_irq(haptics->dev, client->irq, NULL,
					aw86927_irq, IRQF_ONESHOT, NULL, haptics);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to request threaded irq\n");

	INIT_WORK(&haptics->play_work, aw86927_haptics_play_work);

	haptics->input_dev->name = "aw86927-haptics";
	haptics->input_dev->close = aw86927_close;

	input_set_drvdata(haptics->input_dev, haptics);
	input_set_capability(haptics->input_dev, EV_FF, FF_RUMBLE);

	err = input_ff_create_memless(haptics->input_dev, NULL, aw86927_haptics_play);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to create FF dev\n");

	/* Set up registers */
	err = aw86927_play_mode(haptics, AW86927_STANDBY_MODE);
	if (err)
		return dev_err_probe(haptics->dev, err,
				     "Failed to enter standby for Haptic init\n");

	err = aw86927_haptic_init(haptics);
	if (err)
		return dev_err_probe(haptics->dev, err, "Haptic init failed\n");

	/* RAM init, upload the waveform for playback */
	err = aw86927_ram_init(haptics);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to init aw86927 sram\n");

	err = input_register_device(haptics->input_dev);
	if (err)
		return dev_err_probe(haptics->dev, err, "Failed to register input device\n");

	return 0;
}

static const struct of_device_id aw86927_of_id[] = {
	{ .compatible = "awinic,aw86927" },
	{ /* sentinel */ }
};

MODULE_DEVICE_TABLE(of, aw86927_of_id);

static struct i2c_driver aw86927_driver = {
	.driver = {
		.name = "aw86927-haptics",
		.of_match_table = aw86927_of_id,
	},
	.probe = aw86927_probe,
};

module_i2c_driver(aw86927_driver);

MODULE_AUTHOR("Griffin Kroah-Hartman <griffin.kroah@fairphone.com>");
MODULE_DESCRIPTION("AWINIC AW86927 LRA Haptic Driver");
MODULE_LICENSE("GPL");