diff mbox series

[v3,2/6] input: add Qualcomm SPMI haptics driver

Message ID 20210816221931.1998187-3-caleb@connolly.tech (mailing list archive)
State New
Headers show
Series input: Introduce support for SPMI haptics found on Qcom PMICs | expand

Commit Message

Caleb Connolly Aug. 16, 2021, 10:20 p.m. UTC
Add support for the haptics found in pmi8998 and related PMICs.
Based on the ff-memless interface. Currently this driver provides
a partial implementation of hardware features.

This driver only supports LRAs (Linear Resonant Actuators) in the "buffer"
mode with a single wave pattern.

Signed-off-by: Caleb Connolly <caleb@connolly.tech>
---
 drivers/input/misc/Kconfig             |  12 +
 drivers/input/misc/Makefile            |   1 +
 drivers/input/misc/qcom-spmi-haptics.c | 981 +++++++++++++++++++++++++
 3 files changed, 994 insertions(+)
 create mode 100644 drivers/input/misc/qcom-spmi-haptics.c

--
2.32.0
diff mbox series

Patch

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 498cde376981..de422aeb8e5f 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -186,6 +186,18 @@  config INPUT_PMIC8XXX_PWRKEY
 	  To compile this driver as a module, choose M here: the
 	  module will be called pmic8xxx-pwrkey.

+config INPUT_QCOM_SPMI_HAPTICS
+	tristate "Qualcomm SPMI HAPTICS"
+	depends on ARCH_QCOM
+	depends on SPMI
+	select INPUT_FF_MEMLESS
+	help
+	  This option enables support for the haptics found in pmi8998 and
+	  related PMICs. Based on the ff-memless interface.
+
+	  To compile this driver as module, choose M here: the
+	  module will be called qcom_spmi_haptics.
+
 config INPUT_SPARCSPKR
 	tristate "SPARC Speaker support"
 	depends on PCI && SPARC64
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index f593beed7e05..bf5579f335d5 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -65,6 +65,7 @@  obj-$(CONFIG_INPUT_PMIC8XXX_PWRKEY)	+= pmic8xxx-pwrkey.o
 obj-$(CONFIG_INPUT_POWERMATE)		+= powermate.o
 obj-$(CONFIG_INPUT_PWM_BEEPER)		+= pwm-beeper.o
 obj-$(CONFIG_INPUT_PWM_VIBRA)		+= pwm-vibra.o
+obj-$(CONFIG_INPUT_QCOM_SPMI_HAPTICS)	+= qcom-spmi-haptics.o
 obj-$(CONFIG_INPUT_RAVE_SP_PWRBUTTON)	+= rave-sp-pwrbutton.o
 obj-$(CONFIG_INPUT_RB532_BUTTON)	+= rb532_button.o
 obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)	+= regulator-haptic.o
diff --git a/drivers/input/misc/qcom-spmi-haptics.c b/drivers/input/misc/qcom-spmi-haptics.c
new file mode 100644
index 000000000000..aad8a0be6792
--- /dev/null
+++ b/drivers/input/misc/qcom-spmi-haptics.c
@@ -0,0 +1,981 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, Caleb Connolly <caleb@connolly.tech>
+ * Qualcomm QPMI haptics driver for pmi8998 and related PMICs.
+ */
+
+#include <dt-bindings/input/qcom,spmi-haptics.h>
+
+#include <linux/atomic.h>
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/errno.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/types.h>
+
+
+#define HAP_STATUS_1_REG		0x0A
+#define HAP_BUSY_BIT			BIT(1)
+#define SC_FLAG_BIT			BIT(3)
+#define AUTO_RES_ERROR_BIT		BIT(4)
+
+#define HAP_LRA_AUTO_RES_LO_REG		0x0B
+#define HAP_LRA_AUTO_RES_HI_REG		0x0C
+
+#define HAP_EN_CTL_REG			0x46
+#define HAP_EN_BIT			BIT(7)
+
+#define HAP_EN_CTL2_REG			0x48
+#define BRAKE_EN_BIT			BIT(0)
+
+#define HAP_AUTO_RES_CTRL_REG		0x4B
+#define AUTO_RES_EN_BIT			BIT(7)
+#define AUTO_RES_ERR_RECOVERY_BIT	BIT(3)
+#define AUTO_RES_EN_FLAG_BIT		BIT(0)
+
+#define HAP_CFG1_REG			0x4C
+#define HAP_ACT_TYPE_MASK		BIT(0)
+
+#define HAP_CFG2_REG			0x4D
+#define HAP_LRA_RES_TYPE_MASK		BIT(0)
+
+#define HAP_SEL_REG			0x4E
+#define HAP_WF_SOURCE_MASK		GENMASK(5, 4)
+#define HAP_WF_SOURCE_SHIFT		4
+
+#define HAP_LRA_AUTO_RES_REG		0x4F
+#define LRA_AUTO_RES_MODE_MASK		GENMASK(6, 4)
+#define LRA_AUTO_RES_MODE_SHIFT		4
+#define LRA_HIGH_Z_MASK			GENMASK(3, 2)
+#define LRA_HIGH_Z_SHIFT		2
+#define LRA_RES_CAL_MASK		GENMASK(1, 0)
+#define HAP_RES_CAL_PERIOD_MIN		4
+#define HAP_RES_CAL_PERIOD_MAX		32
+
+#define HAP_VMAX_CFG_REG			0x51
+#define HAP_VMAX_OVD_BIT		BIT(6)
+#define HAP_VMAX_MASK			GENMASK(5, 1)
+#define HAP_VMAX_SHIFT			1
+
+#define HAP_ILIM_CFG_REG			0x52
+#define HAP_ILIM_SEL_MASK		BIT(0)
+#define HAP_ILIM_400_MA			0
+#define HAP_ILIM_800_MA			1
+
+#define HAP_SC_DEB_REG			0x53
+#define HAP_SC_DEB_MASK			GENMASK(2, 0)
+#define HAP_SC_DEB_CYCLES_MIN		0
+#define HAP_DEF_SC_DEB_CYCLES		8
+#define HAP_SC_DEB_CYCLES_MAX		32
+
+#define HAP_RATE_CFG1_REG		0x54
+#define HAP_RATE_CFG1_MASK		GENMASK(7, 0)
+#define HAP_RATE_CFG2_SHIFT		8 // As CFG2 is the most significant byte
+
+#define HAP_RATE_CFG2_REG		0x55
+#define HAP_RATE_CFG2_MASK		GENMASK(3, 0)
+
+#define HAP_SC_CLR_REG			0x59
+#define SC_CLR_BIT			BIT(0)
+
+#define HAP_BRAKE_REG			0x5C
+#define HAP_BRAKE_PAT_MASK		0x3
+
+#define HAP_WF_REPEAT_REG			0x5E
+#define WF_REPEAT_MASK			GENMASK(6, 4)
+#define WF_REPEAT_SHIFT			4
+#define WF_REPEAT_MIN			1
+#define WF_REPEAT_MAX			128
+#define WF_S_REPEAT_MASK		GENMASK(1, 0)
+#define WF_S_REPEAT_MIN			1
+#define WF_S_REPEAT_MAX			8
+
+#define HAP_WF_S1_REG			0x60
+#define HAP_WF_SIGN_BIT			BIT(7)
+#define HAP_WF_OVD_BIT			BIT(6)
+#define HAP_WF_SAMP_MAX			GENMASK(5, 1)
+#define HAP_WF_SAMPLE_LEN		8
+
+#define HAP_PLAY_REG			0x70
+#define HAP_PLAY_BIT			BIT(7)
+#define HAP_PAUSE_BIT			BIT(0)
+
+#define HAP_SEC_ACCESS_REG		0xD0
+#define HAP_SEC_ACCESS_UNLOCK		0xA5
+
+#define HAP_TEST2_REG			0xE3
+
+
+#define HAP_VMAX_MIN_MV			116
+#define HAP_VMAX_MAX_MV			3596
+#define HAP_VMAX_MAX_MV_STRONG		3596
+
+#define HAP_WAVE_PLAY_RATE_MIN_US	0
+#define HAP_WAVE_PLAY_RATE_MAX_US	20475
+#define HAP_WAVE_PLAY_TIME_MAX_MS	15000
+
+#define AUTO_RES_ERR_POLL_TIME_NS	(20 * NSEC_PER_MSEC)
+#define HAPTICS_BACK_EMF_DELAY_US	20000
+
+#define HAP_BRAKE_PAT_LEN		4
+#define HAP_WAVE_SAMP_LEN		8
+#define NUM_WF_SET			4
+#define HAP_WAVE_SAMP_SET_LEN		(HAP_WAVE_SAMP_LEN * NUM_WF_SET)
+#define HAP_RATE_CFG_STEP_US		5
+
+#define SC_MAX_COUNT			5
+#define SC_COUNT_RST_DELAY_US		1000000
+
+enum hap_play_control {
+	HAP_STOP,
+	HAP_PAUSE,
+	HAP_PLAY,
+};
+
+/**
+ * struct spmi_haptics - struct for spmi haptics data.
+ *
+ * @dev: Our device parent.
+ * @regmap: Register map for the hardware block.
+ * @input_dev: The input device used to receive events.
+ * @work: Work struct to play effects.
+ * @base: Base address of the regmap.
+ * @active: Atomic value used to track if haptics are currently playing.
+ * @play_irq: Fired to load the next wave pattern.
+ * @sc_irq: Short circuit irq.
+ * @last_sc_time: Time since the short circuit IRQ last fired.
+ * @sc_count: Number of times the short circuit IRQ has fired in this interval.
+ * @actuator_type: The type of actuator in use.
+ * @wave_shape: The shape of the waves to use (sine or square).
+ * @play_mode: The play mode to use (direct, buffer, pwm, audio).
+ * @magnitude: The strength we should be playing at.
+ * @vmax: Max voltage to use when playing.
+ * @current_limit: The current limit for this hardware (400mA or 800mA).
+ * @play_wave_rate: The wave rate to use for this hardware.
+ * @wave_samp: The array of wave samples to write for buffer mode.
+ * @brake_pat: The pattern to apply when braking.
+ * @play_lock: Lock to be held when updating the hardware state.
+ */
+struct spmi_haptics {
+	struct device *dev;
+	struct regmap *regmap;
+	struct input_dev *haptics_input_dev;
+	struct work_struct work;
+	u32 base;
+
+	atomic_t active;
+
+	int play_irq;
+	int sc_irq;
+	ktime_t last_sc_time;
+	u8 sc_count;
+
+	u8 actuator_type;
+	u8 wave_shape;
+	u8 play_mode;
+	int magnitude;
+	u32 vmax;
+	u32 current_limit;
+	u32 play_wave_rate;
+
+	u32 wave_samp[HAP_WAVE_SAMP_SET_LEN];
+	u8 brake_pat[HAP_BRAKE_PAT_LEN];
+
+	struct mutex play_lock;
+};
+
+static inline bool is_secure_addr(u16 addr)
+{
+	return (addr & 0xFF) > 0xD0;
+}
+
+static int spmi_haptics_read(struct spmi_haptics *haptics,
+	u16 addr, u8 *val, int len)
+{
+	int ret;
+
+	ret = regmap_bulk_read(haptics->regmap, addr, val, len);
+	if (ret < 0)
+		dev_err(haptics->dev, "Error reading address: 0x%x, ret %d\n", addr, ret);
+
+	return ret;
+}
+
+static int spmi_haptics_write(struct spmi_haptics *haptics,
+			      u16 addr, u8 *val, int len)
+{
+	int ret, i;
+
+	if (is_secure_addr(addr)) {
+		for (i = 0; i < len; i++) {
+			dev_dbg(haptics->dev, "%s: unlocking for addr: 0x%x, val: 0x%x", __func__,
+				addr, val[i]);
+			ret = regmap_write(haptics->regmap,
+				haptics->base + HAP_SEC_ACCESS_REG, HAP_SEC_ACCESS_UNLOCK);
+			if (ret < 0) {
+				dev_err(haptics->dev, "Error writing unlock code, ret %d\n",
+					ret);
+				return ret;
+			}
+
+			ret = regmap_write(haptics->regmap, addr + i, val[i]);
+			if (ret < 0) {
+				dev_err(haptics->dev, "Error writing address 0x%x, ret %d\n",
+					addr + i, ret);
+				return ret;
+			}
+		}
+	} else {
+		if (len > 1)
+			ret = regmap_bulk_write(haptics->regmap, addr, val, len);
+		else
+			ret = regmap_write(haptics->regmap, addr, *val);
+	}
+
+	if (ret < 0)
+		dev_err(haptics->dev, "%s: Error writing address: 0x%x, ret %d\n",
+			__func__, addr, ret);
+
+	return ret;
+}
+
+static int spmi_haptics_write_masked(struct spmi_haptics *haptics,
+	u16 addr, u8 mask, u8 val)
+{
+	int ret;
+
+	if (is_secure_addr(addr)) {
+		ret = regmap_write(haptics->regmap,
+			haptics->base + HAP_SEC_ACCESS_REG, HAP_SEC_ACCESS_UNLOCK);
+		if (ret < 0) {
+			dev_err(haptics->dev, "Error writing unlock code - ret %d\n", ret);
+			return ret;
+		}
+	}
+
+	ret = regmap_update_bits(haptics->regmap, addr, mask, val);
+	if (ret < 0)
+		dev_err(haptics->dev, "Error writing address: 0x%x - ret %d\n", addr, ret);
+
+	return ret;
+}
+
+static bool is_haptics_idle(struct spmi_haptics *haptics)
+{
+	int ret;
+	u8 val;
+
+	if (haptics->play_mode == HAP_PLAY_DIRECT ||
+			haptics->play_mode == HAP_PLAY_PWM)
+		return true;
+
+	ret = spmi_haptics_read(haptics, haptics->base + HAP_STATUS_1_REG, &val, 1);
+	if (ret < 0 || (val & HAP_BUSY_BIT))
+		return false;
+
+	return true;
+}
+
+static int spmi_haptics_module_enable(struct spmi_haptics *haptics, bool enable)
+{
+	u8 val;
+
+	dev_dbg(haptics->dev, "Setting module enable: %d", enable);
+
+	val = enable ? HAP_EN_BIT : 0;
+	return spmi_haptics_write(haptics, haptics->base + HAP_EN_CTL_REG, &val, 1);
+}
+
+static int spmi_haptics_write_vmax(struct spmi_haptics *haptics)
+{
+	u8 val = 0;
+	u32 vmax_mv = haptics->vmax;
+
+	vmax_mv = clamp_t(u32, vmax_mv, HAP_VMAX_MIN_MV, HAP_VMAX_MAX_MV);
+
+	dev_dbg(haptics->dev, "Setting vmax to: %d", vmax_mv);
+
+	val = DIV_ROUND_CLOSEST(vmax_mv, HAP_VMAX_MIN_MV);
+	val = FIELD_PREP(HAP_VMAX_MASK, val);
+
+	// TODO: pm660 can enable overdrive here
+
+	return spmi_haptics_write_masked(haptics, haptics->base + HAP_VMAX_CFG_REG,
+					 HAP_VMAX_MASK | HAP_WF_OVD_BIT, val);
+}
+
+static int spmi_haptics_write_current_limit(struct spmi_haptics *haptics)
+{
+	haptics->current_limit = clamp_t(u32, haptics->current_limit,
+					 HAP_ILIM_400_MA, HAP_ILIM_800_MA);
+
+	dev_dbg(haptics->dev, "Setting current_limit to: 0x%x", haptics->current_limit);
+
+	return spmi_haptics_write_masked(haptics, haptics->base + HAP_ILIM_CFG_REG,
+			HAP_ILIM_SEL_MASK, haptics->current_limit);
+}
+
+static int spmi_haptics_write_play_mode(struct spmi_haptics *haptics)
+{
+	u8 val = 0;
+
+	if (!is_haptics_idle(haptics))
+		return -EBUSY;
+
+	dev_dbg(haptics->dev, "Setting play_mode to: 0x%x", haptics->play_mode);
+
+	val = FIELD_PREP(HAP_WF_SOURCE_MASK, haptics->play_mode);
+	return spmi_haptics_write_masked(haptics, haptics->base + HAP_SEL_REG,
+					 HAP_WF_SOURCE_MASK, val);
+
+}
+
+static int spmi_haptics_write_play_rate(struct spmi_haptics *haptics, u16 play_rate)
+{
+	u8 val[2];
+
+	dev_dbg(haptics->dev, "Setting play_rate to: %d", play_rate);
+
+	val[0] = FIELD_PREP(HAP_RATE_CFG1_MASK, play_rate);
+	val[1] = FIELD_PREP(HAP_RATE_CFG2_MASK, play_rate >> HAP_RATE_CFG2_SHIFT);
+	return spmi_haptics_write(haptics, haptics->base + HAP_RATE_CFG1_REG, val, 2);
+}
+
+/*
+ * spmi_haptics_set_auto_res() - Auto resonance
+ * allows the haptics to automatically adjust the
+ * speed of the oscillation in order to maintain
+ * the resonant frequency.
+ */
+static int spmi_haptics_set_auto_res(struct spmi_haptics *haptics, bool enable)
+{
+	u8 val;
+
+	// LRAs are the only type to support auto res
+	if (haptics->actuator_type != HAP_TYPE_LRA)
+		return 0;
+
+	val = enable ? AUTO_RES_EN_BIT : 0;
+
+	return spmi_haptics_write_masked(haptics, haptics->base + HAP_TEST2_REG,
+				       AUTO_RES_EN_BIT, val);
+}
+
+static int spmi_haptics_write_brake(struct spmi_haptics *haptics)
+{
+	int ret, i;
+	u8 val;
+
+	dev_dbg(haptics->dev, "Configuring brake pattern");
+
+	ret = spmi_haptics_write_masked(haptics, haptics->base + HAP_EN_CTL2_REG,
+					BRAKE_EN_BIT, 1);
+	if (ret < 0)
+		return ret;
+
+	for (i = HAP_BRAKE_PAT_LEN - 1, val = 0; i >= 0; i--) {
+		u8 p = haptics->brake_pat[i] & HAP_BRAKE_PAT_MASK;
+
+		val |= p << (i * 2);
+	}
+
+	return spmi_haptics_write(haptics, haptics->base + HAP_BRAKE_REG, &val, 1);
+}
+
+static int spmi_haptics_write_buffer_config(struct spmi_haptics *haptics)
+{
+	u8 buf[HAP_WAVE_SAMP_LEN];
+	int i;
+
+	dev_dbg(haptics->dev, "Writing buffer config");
+
+	for (i = 0; i < HAP_WAVE_SAMP_LEN; i++)
+		buf[i] = haptics->wave_samp[i];
+
+	return spmi_haptics_write(haptics, haptics->base + HAP_WF_S1_REG, buf,
+				  HAP_WAVE_SAMP_LEN);
+}
+
+/*
+ * spmi_haptics_write_wave_repeat() - write wave repeat values.
+ */
+static int spmi_haptics_write_wave_repeat(struct spmi_haptics *haptics)
+{
+	u8 val, mask;
+
+	/* The number of times to repeat each wave */
+	mask = WF_REPEAT_MASK | WF_S_REPEAT_MASK;
+	val = FIELD_PREP(WF_REPEAT_MASK, 0) |
+	      FIELD_PREP(WF_S_REPEAT_MASK, 0);
+
+	return spmi_haptics_write_masked(haptics, haptics->base + HAP_WF_REPEAT_REG,
+					 mask, val);
+}
+
+static int spmi_haptics_write_play_control(struct spmi_haptics *haptics,
+						enum hap_play_control ctrl)
+{
+	u8 val;
+
+	switch (ctrl) {
+	case HAP_STOP:
+		val = 0;
+		break;
+	case HAP_PAUSE:
+		val = HAP_PAUSE_BIT;
+		break;
+	case HAP_PLAY:
+		val = HAP_PLAY_BIT;
+		break;
+	default:
+		return 0;
+	}
+
+	dev_dbg(haptics->dev, "haptics play ctrl: %d\n", ctrl);
+	return spmi_haptics_write(haptics, haptics->base + HAP_PLAY_REG, &val, 1);
+}
+
+/*
+ * This IRQ is fired to tell us to load the next wave sample set.
+ * As we only currently support a single sample set, it's unused.
+ */
+static irqreturn_t spmi_haptics_play_irq_handler(int irq, void *data)
+{
+	struct spmi_haptics *haptics = data;
+
+	dev_dbg(haptics->dev, "play_irq triggered");
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Fires every ~50ms whilst the haptics are active.
+ * If the SC_FLAG_BIT is set then that means there isn't a short circuit
+ * and we just need to clear the IRQ to indicate that the device should
+ * keep vibrating.
+ *
+ * Otherwise, it means a short circuit situation has occurred.
+ */
+static irqreturn_t spmi_haptics_sc_irq_handler(int irq, void *data)
+{
+	struct spmi_haptics *haptics = data;
+	int ret;
+	u8 val;
+	s64 sc_delta_time_us;
+	ktime_t temp;
+
+	ret = spmi_haptics_read(haptics, haptics->base + HAP_STATUS_1_REG, &val, 1);
+	if (ret < 0)
+		return IRQ_HANDLED;
+
+	if (!(val & SC_FLAG_BIT)) {
+		haptics->sc_count = 0;
+		return IRQ_HANDLED;
+	}
+
+	temp = ktime_get();
+	sc_delta_time_us = ktime_us_delta(temp, haptics->last_sc_time);
+	haptics->last_sc_time = temp;
+
+	if (sc_delta_time_us > SC_COUNT_RST_DELAY_US)
+		haptics->sc_count = 0;
+	else
+		haptics->sc_count++;
+
+	// Clear the interrupt flag
+	val = SC_CLR_BIT;
+	ret = spmi_haptics_write(haptics, haptics->base + HAP_SC_CLR_REG, &val, 1);
+	if (ret < 0)
+		return IRQ_HANDLED;
+
+	if (haptics->sc_count > SC_MAX_COUNT) {
+		dev_crit(haptics->dev, "Short circuit persists, disabling haptics\n");
+		ret = spmi_haptics_module_enable(haptics, false);
+		if (ret < 0)
+			dev_err(haptics->dev, "Error disabling module, rc=%d\n", ret);
+	}
+
+	return IRQ_HANDLED;
+}
+
+
+/**
+ * spmi_haptics_init() - Initialise haptics hardware for use
+ * @haptics: haptics device
+ * Returns: 0 on success, < 0 on error
+ */
+static int spmi_haptics_init(struct spmi_haptics *haptics)
+{
+	int ret;
+	u8 val, mask;
+	u16 play_rate;
+
+	ret = spmi_haptics_write_masked(haptics, haptics->base + HAP_CFG1_REG,
+		HAP_ACT_TYPE_MASK, haptics->actuator_type);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Configure auto resonance
+	 * see spmi_haptics_lra_auto_res_config downstream
+	 * This is greatly simplified.
+	 */
+	val = FIELD_PREP(LRA_RES_CAL_MASK, ilog2(32 / HAP_RES_CAL_PERIOD_MIN)) |
+	      FIELD_PREP(LRA_AUTO_RES_MODE_MASK, HAP_AUTO_RES_ZXD_EOP) |
+	      FIELD_PREP(LRA_HIGH_Z_MASK, 1);
+
+	mask = LRA_AUTO_RES_MODE_MASK | LRA_HIGH_Z_MASK | LRA_RES_CAL_MASK;
+
+	ret = spmi_haptics_write_masked(haptics, haptics->base + HAP_LRA_AUTO_RES_REG,
+			mask, val);
+
+	/* Configure the PLAY MODE register */
+	ret = spmi_haptics_write_play_mode(haptics);
+	if (ret < 0)
+		return ret;
+
+	ret = spmi_haptics_write_vmax(haptics);
+	if (ret < 0)
+		return ret;
+
+	/* Configure the ILIM register */
+	ret = spmi_haptics_write_current_limit(haptics);
+	if (ret < 0)
+		return ret;
+
+	// Configure the debounce for short-circuit detection.
+	ret = spmi_haptics_write_masked(haptics, haptics->base + HAP_SC_DEB_REG,
+			HAP_SC_DEB_MASK, HAP_SC_DEB_CYCLES_MAX);
+	if (ret < 0)
+		return ret;
+
+	// write the wave shape
+	ret = spmi_haptics_write_masked(haptics, haptics->base + HAP_CFG2_REG,
+			HAP_LRA_RES_TYPE_MASK, haptics->wave_shape);
+	if (ret < 0)
+		return ret;
+
+	play_rate = haptics->play_wave_rate / HAP_RATE_CFG_STEP_US;
+
+	/*
+	 * Configure RATE_CFG1 and RATE_CFG2 registers.
+	 * Note: For ERM these registers act as play rate and
+	 * for LRA these represent resonance period
+	 */
+	ret = spmi_haptics_write_play_rate(haptics, play_rate);
+	if (ret < 0)
+		return ret;
+
+	ret = spmi_haptics_write_brake(haptics);
+	if (ret < 0)
+		return ret;
+
+	if (haptics->play_mode == HAP_PLAY_BUFFER) {
+		ret = spmi_haptics_write_wave_repeat(haptics);
+		if (ret < 0)
+			return ret;
+
+		ret = spmi_haptics_write_buffer_config(haptics);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (haptics->play_irq >= 0) {
+		dev_dbg(haptics->dev, "%s: Requesting play IRQ, irq: %d", __func__,
+			haptics->play_irq);
+		ret = devm_request_threaded_irq(haptics->dev, haptics->play_irq,
+			NULL, spmi_haptics_play_irq_handler, IRQF_ONESHOT,
+			"haptics_play_irq", haptics);
+
+		if (ret < 0) {
+			dev_err(haptics->dev, "Unable to request play IRQ ret=%d\n", ret);
+			return ret;
+		}
+
+		/* use play_irq only for buffer mode */
+		if (haptics->play_mode != HAP_PLAY_BUFFER)
+			disable_irq(haptics->play_irq);
+	}
+
+	if (haptics->sc_irq >= 0) {
+		dev_dbg(haptics->dev, "%s: Requesting play IRQ, irq: %d", __func__,
+			haptics->play_irq);
+		ret = devm_request_threaded_irq(haptics->dev, haptics->sc_irq,
+			NULL, spmi_haptics_sc_irq_handler, IRQF_ONESHOT,
+			"haptics_sc_irq", haptics);
+
+		if (ret < 0) {
+			dev_err(haptics->dev, "Unable to request sc IRQ ret=%d\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * spmi_haptics_enable - handler to start/stop vibration
+ * @haptics: pointer to haptics struct
+ * @enable: state to set
+ * Returns: 0 on success, < 0 on failure
+ */
+static int spmi_haptics_enable(struct spmi_haptics *haptics)
+{
+	int ret;
+
+	mutex_lock(&haptics->play_lock);
+	if (haptics->sc_count > SC_MAX_COUNT) {
+		dev_err(haptics->dev, "Can't play while in short circuit");
+		ret = -1;
+		goto out;
+	}
+	ret = spmi_haptics_set_auto_res(haptics, false);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Error disabling auto_res, ret=%d\n", ret);
+		goto out;
+	}
+
+	ret = spmi_haptics_module_enable(haptics, true);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Error enabling module, ret=%d\n", ret);
+		goto out;
+	}
+
+	ret = spmi_haptics_write_play_control(haptics, HAP_PLAY);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Error enabling play, ret=%d\n", ret);
+		goto out;
+	}
+
+	ret = spmi_haptics_set_auto_res(haptics, true);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Error enabling auto_res, ret=%d\n", ret);
+		goto out;
+	}
+
+out:
+	mutex_unlock(&haptics->play_lock);
+	return ret;
+}
+
+/**
+ * spmi_haptics_enable - handler to start/stop vibration
+ * @haptics: pointer to haptics struct
+ * @enable: state to set
+ * Returns: 0 on success, < 0 on failure
+ */
+static int spmi_haptics_disable(struct spmi_haptics *haptics)
+{
+	int ret;
+
+	mutex_lock(&haptics->play_lock);
+
+	ret = spmi_haptics_write_play_control(haptics, HAP_STOP);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Error disabling play, ret=%d\n", ret);
+		goto out;
+	}
+
+	ret = spmi_haptics_module_enable(haptics, false);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Error disabling module, ret=%d\n", ret);
+		goto out;
+	}
+
+out:
+	mutex_unlock(&haptics->play_lock);
+	return ret;
+}
+
+/*
+ * Threaded function to update the haptics state.
+ */
+static void spmi_haptics_work(struct work_struct *work)
+{
+	struct spmi_haptics *haptics = container_of(work, struct spmi_haptics, work);
+
+	int ret;
+	bool enable;
+
+	enable = atomic_read(&haptics->active);
+	dev_dbg(haptics->dev, "%s: state: %d\n", __func__, enable);
+
+	if (enable)
+		ret = spmi_haptics_enable(haptics);
+	else
+		ret = spmi_haptics_disable(haptics);
+	if (ret < 0)
+		dev_err(haptics->dev, "Error setting haptics, ret=%d", ret);
+}
+
+/**
+ * spmi_haptics_close - callback for input device close
+ * @dev: input device pointer
+ *
+ * Turns off the vibrator.
+ */
+static void spmi_haptics_close(struct input_dev *dev)
+{
+	struct spmi_haptics *haptics = input_get_drvdata(dev);
+
+	cancel_work_sync(&haptics->work);
+	if (atomic_read(&haptics->active)) {
+		atomic_set(&haptics->active, 0);
+		schedule_work(&haptics->work);
+	}
+}
+
+/**
+ * spmi_haptics_play_effect - play haptics effects
+ * @dev: input device pointer
+ * @data: data of effect
+ * @effect: effect to play
+ */
+static int spmi_haptics_play_effect(struct input_dev *dev, void *data,
+					struct ff_effect *effect)
+{
+	struct spmi_haptics *haptics = input_get_drvdata(dev);
+
+	dev_dbg(haptics->dev, "%s: Rumbling with strong: %d and weak: %d", __func__,
+		effect->u.rumble.strong_magnitude, effect->u.rumble.weak_magnitude);
+
+	haptics->magnitude = effect->u.rumble.strong_magnitude >> 8;
+	if (!haptics->magnitude)
+		haptics->magnitude = effect->u.rumble.weak_magnitude >> 10;
+
+	if (!haptics->magnitude) {
+		atomic_set(&haptics->active, 0);
+		goto end;
+	}
+
+	atomic_set(&haptics->active, 1);
+
+	haptics->vmax = ((HAP_VMAX_MAX_MV - HAP_VMAX_MIN_MV) * haptics->magnitude) / 100 +
+					HAP_VMAX_MIN_MV;
+
+	dev_dbg(haptics->dev, "%s: magnitude: %d, vmax: %d", __func__,
+		haptics->magnitude, haptics->vmax);
+
+	spmi_haptics_write_vmax(haptics);
+
+end:
+	schedule_work(&haptics->work);
+
+	return 0;
+}
+
+static int spmi_haptics_probe(struct platform_device *pdev)
+{
+	struct spmi_haptics *haptics;
+	struct device_node *node;
+	struct input_dev *input_dev;
+	int ret;
+	u32 val;
+	int i;
+
+	haptics = devm_kzalloc(&pdev->dev, sizeof(*haptics), GFP_KERNEL);
+	if (!haptics)
+		return -ENOMEM;
+
+	haptics->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!haptics->regmap)
+		return -ENODEV;
+
+	node = pdev->dev.of_node;
+
+	haptics->dev = &pdev->dev;
+
+	ret = of_property_read_u32(node, "reg", &haptics->base);
+	if (ret < 0) {
+		dev_err(haptics->dev, "Couldn't find reg in node = %s ret = %d\n",
+			node->full_name, ret);
+		return ret;
+	}
+
+	haptics->play_irq = platform_get_irq_byname(pdev, "play");
+	if (haptics->play_irq < 0) {
+		dev_err(&pdev->dev, "Unable to get play irq\n");
+		ret = haptics->play_irq;
+		goto register_fail;
+	}
+
+	haptics->sc_irq = platform_get_irq_byname(pdev, "short");
+	if (haptics->sc_irq < 0) {
+		dev_err(&pdev->dev, "Unable to get sc irq\n");
+		ret = haptics->sc_irq;
+		goto register_fail;
+	}
+
+	// We only support LRAs for now
+	haptics->actuator_type = HAP_TYPE_LRA;
+	ret = of_property_read_u32(node, "qcom,actuator-type", &val);
+	if (!ret) {
+		if (val != HAP_TYPE_LRA) {
+			dev_err(&pdev->dev, "qcom,actuator-type (%d) isn't supported\n", val);
+			ret = -EINVAL;
+			goto register_fail;
+		}
+		haptics->actuator_type = val;
+	}
+
+	// Only buffer mode is currently supported
+	haptics->play_mode = HAP_PLAY_BUFFER;
+	ret = of_property_read_u32(node, "qcom,play-mode", &val);
+	if (!ret) {
+		if (val != HAP_PLAY_BUFFER) {
+			dev_err(&pdev->dev, "qcom,play-mode (%d) isn't supported\n", val);
+			ret = -EINVAL;
+			goto register_fail;
+		}
+		haptics->play_mode = val;
+	}
+
+	ret = of_property_read_u32(node, "qcom,wave-play-rate-us", &val);
+	if (!ret) {
+		haptics->play_wave_rate = val;
+	} else if (ret != -EINVAL) {
+		dev_err(haptics->dev, "Unable to read play rate ret=%d\n", ret);
+		goto register_fail;
+	}
+
+	haptics->play_wave_rate =
+		clamp_t(u32, haptics->play_wave_rate,
+			HAP_WAVE_PLAY_RATE_MIN_US, HAP_WAVE_PLAY_RATE_MAX_US);
+
+	haptics->wave_shape = HAP_WAVE_SINE;
+	ret = of_property_read_u32(node, "qcom,wave-shape", &val);
+	if (!ret) {
+		if (val != HAP_WAVE_SINE && val != HAP_WAVE_SQUARE) {
+			dev_err(&pdev->dev, "qcom,wave-shape is invalid: %d\n", val);
+			ret = -EINVAL;
+			goto register_fail;
+		}
+		haptics->wave_shape = val;
+	}
+
+	haptics->brake_pat[0] = 0x3;
+	haptics->brake_pat[1] = 0x3;
+	haptics->brake_pat[2] = 0x2;
+	haptics->brake_pat[3] = 0x1;
+
+	ret = of_property_read_u8_array(node, "qcom,brake-pattern", haptics->brake_pat, 4);
+	if (ret < 0 && ret != -EINVAL) {
+		dev_err(&pdev->dev, "qcom,brake-pattern is invalid, ret = %d\n", ret);
+		goto register_fail;
+	}
+
+	haptics->current_limit = HAP_ILIM_400_MA;
+
+	for (i = 0; i < HAP_WAVE_SAMP_LEN; i++)
+		haptics->wave_samp[i] = HAP_WF_SAMP_MAX;
+
+	ret = spmi_haptics_init(haptics);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Error initialising haptics, ret=%d\n",
+			ret);
+		goto register_fail;
+	}
+
+	platform_set_drvdata(pdev, haptics);
+
+	input_dev = devm_input_allocate_device(&pdev->dev);
+	if (!input_dev)
+		return -ENOMEM;
+
+	INIT_WORK(&haptics->work, spmi_haptics_work);
+	haptics->haptics_input_dev = input_dev;
+
+	input_dev->name = "spmi_haptics";
+	input_dev->id.version = 1;
+	input_dev->close = spmi_haptics_close;
+	input_set_drvdata(input_dev, haptics);
+	// Figure out how to make this FF_PERIODIC
+	input_set_capability(haptics->haptics_input_dev, EV_FF, FF_RUMBLE);
+
+	ret = input_ff_create_memless(input_dev, NULL,
+					spmi_haptics_play_effect);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"couldn't register vibrator as FF device\n");
+		goto register_fail;
+	}
+
+	ret = input_register_device(input_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "couldn't register input device\n");
+		goto register_fail;
+	}
+
+	return 0;
+
+register_fail:
+	cancel_work_sync(&haptics->work);
+	mutex_destroy(&haptics->play_lock);
+
+	return ret;
+}
+
+static int __maybe_unused spmi_haptics_suspend(struct device *dev)
+{
+	struct spmi_haptics *haptics = dev_get_drvdata(dev);
+
+	cancel_work_sync(&haptics->work);
+	spmi_haptics_disable(haptics);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(spmi_haptics_pm_ops, spmi_haptics_suspend, NULL);
+
+static int spmi_haptics_remove(struct platform_device *pdev)
+{
+	struct spmi_haptics *haptics = dev_get_drvdata(&pdev->dev);
+
+	cancel_work_sync(&haptics->work);
+	mutex_destroy(&haptics->play_lock);
+	input_unregister_device(haptics->haptics_input_dev);
+
+	return 0;
+}
+
+static void spmi_haptics_shutdown(struct platform_device *pdev)
+{
+	struct spmi_haptics *haptics = dev_get_drvdata(&pdev->dev);
+
+	cancel_work_sync(&haptics->work);
+
+	spmi_haptics_disable(haptics);
+}
+
+static const struct of_device_id spmi_haptics_match_table[] = {
+	{ .compatible = "qcom,spmi-haptics" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, spmi_haptics_match_table);
+
+static struct platform_driver spmi_haptics_driver = {
+	.probe		= spmi_haptics_probe,
+	.remove		= spmi_haptics_remove,
+	.shutdown	= spmi_haptics_shutdown,
+	.driver		= {
+		.name	= "spmi-haptics",
+		.pm	= &spmi_haptics_pm_ops,
+		.of_match_table = spmi_haptics_match_table,
+	},
+};
+module_platform_driver(spmi_haptics_driver);
+
+MODULE_DESCRIPTION("spmi haptics driver using ff-memless framework");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Caleb Connolly <caleb@connolly.tech>");