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From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Fenglin Wu <fenglin.wu@oss.qualcomm.com>
Cc: linux-arm-msm@vger.kernel.org, Rob Herring <robh@kernel.org>,
	 Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>, Lee Jones <lee@kernel.org>,
	 Stephen Boyd <sboyd@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	 Konrad Dybcio <konradybcio@kernel.org>,
	David Collins <david.collins@oss.qualcomm.com>,
	 Subbaraman Narayanamurthy
	<subbaraman.narayanamurthy@oss.qualcomm.com>,
	Kamal Wadhwa <kamal.wadhwa@oss.qualcomm.com>,
	 kernel@oss.qualcomm.com, linux-input@vger.kernel.org,
	devicetree@vger.kernel.org,  linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 3/3] input: misc: Add Qualcomm SPMI PMIC haptics driver
Date: Fri, 17 Jul 2026 09:51:50 -0700	[thread overview]
Message-ID: <alpWEL1hJgQ18I7d@google.com> (raw)
In-Reply-To: <20260717-qcom-spmi-haptics-v4-3-b0fe0ed30849@oss.qualcomm.com>

Hi Fenglin,

On Fri, Jul 17, 2026 at 12:29:01AM -0700, Fenglin Wu wrote:
> Add an initial driver for the Qualcomm PMIH0108 PMIC haptics module,
> named as HAP530_HV. This module supports several play modes, including
> DIRECT_PLAY, FIFO, PAT_MEM, and SWR, each with distinct data sourcing
> and hardware data handling logic. Currently, the driver provides support
> for two play modes using the input force-feedback framework: FF_CONSTANT
> effect for DIRECT_PLAY mode and FF_PERIODIC effect with FF_CUSTOM
> waveform for FIFO mode.
> 
> Assisted-by: Claude:claude-4-8-opus
> Signed-off-by: Fenglin Wu <fenglin.wu@oss.qualcomm.com>
> ---
>  drivers/input/misc/Kconfig             |   11 +
>  drivers/input/misc/Makefile            |    1 +
>  drivers/input/misc/qcom-spmi-haptics.c | 1178 ++++++++++++++++++++++++++++++++
>  3 files changed, 1190 insertions(+)
> 
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 1f6c57dba030..4f40940973e4 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -236,6 +236,17 @@ 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 PMIC haptics support"
> +	depends on MFD_SPMI_PMIC
> +	help
> +	  Say Y to enable support for the Qualcomm PMIH0108 SPMI PMIC haptics
> +	  module. Supports DIRECT_PLAY, FIFO streaming play modes via the
> +	  Linux input force-feedback framework.
> +
> +	  To compile this driver as a 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 2281d6803fce..c5c9aa139a11 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -69,6 +69,7 @@ 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_QNAP_MCU)		+= qnap-mcu-input.o
>  obj-$(CONFIG_INPUT_RAVE_SP_PWRBUTTON)	+= rave-sp-pwrbutton.o
>  obj-$(CONFIG_INPUT_RB532_BUTTON)	+= rb532_button.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..235f77e0229c
> --- /dev/null
> +++ b/drivers/input/misc/qcom-spmi-haptics.c
> @@ -0,0 +1,1178 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
> +#include <linux/device.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/list.h>
> +#include <linux/math64.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/uaccess.h>
> +#include <linux/workqueue.h>
> +
> +/* HAP_CFG register offsets, bit fields, value constants */
> +#define HAP_CFG_INT_RT_STS_REG		0x10
> +#define  FIFO_EMPTY_BIT			BIT(1)
> +#define HAP_CFG_EN_CTL_REG		0x46
> +#define  HAPTICS_EN_BIT			BIT(7)
> +#define HAP_CFG_VMAX_REG		0x48
> +#define   VMAX_STEP_MV			50
> +#define   VMAX_MV_MAX			10000
> +#define HAP_CFG_SPMI_PLAY_REG		0x4C
> +#define  PLAY_EN_BIT			BIT(7)
> +#define  PAT_SRC_MASK			GENMASK(2, 0)
> +#define   PAT_SRC_FIFO			0
> +#define   PAT_SRC_DIRECT_PLAY		1
> +#define HAP_CFG_TLRA_OL_HIGH_REG	0x5C
> +#define  TLRA_OL_MSB_MASK		GENMASK(3, 0)
> +#define   TLRA_STEP_US			5
> +#define   TLRA_US_MAX			20475
> +#define HAP_CFG_TLRA_OL_LOW_REG		0x5D
> +#define HAP_CFG_DRV_DUTY_CFG_REG	0x60
> +#define  ADT_DRV_DUTY_EN_BIT		BIT(7)
> +#define  ADT_BRK_DUTY_EN_BIT		BIT(6)
> +#define  DRV_DUTY_MASK			GENMASK(5, 3)
> +#define   AUTORES_DRV_DUTY_62P5		2
> +#define  BRK_DUTY_MASK			GENMASK(2, 0)
> +#define   AUTORES_BRK_DUTY_62P5		5
> +#define HAP_CFG_ZX_WIND_CFG_REG		0x62
> +#define  ZX_DEBOUNCE_MASK		GENMASK(6, 4)
> +#define   AUTORES_ZX_DEBOUNCE		3
> +#define  ZX_WIN_HEIGHT_MASK		GENMASK(2, 0)
> +#define   AUTORES_ZX_WIN_HEIGHT		2
> +#define HAP_CFG_AUTORES_CFG_REG		0x63
> +#define  AUTORES_EN_BIT			BIT(7)
> +#define  AUTORES_EN_DLY_MASK		GENMASK(6, 2)
> +#define   AUTORES_EN_DLY_CYCLES		10
> +#define  AUTORES_ERR_WIN_MASK		GENMASK(1, 0)
> +#define   AUTORES_ERR_WIN_25PCT		1
> +#define HAP_CFG_FAULT_CLR_REG		0x66
> +#define  ZX_TO_FAULT_CLR_BIT		BIT(4)
> +#define  SC_CLR_BIT			BIT(2)
> +#define  AUTO_RES_ERR_CLR_BIT		BIT(1)
> +#define  HPWR_RDY_FAULT_CLR_BIT		BIT(0)
> +#define  FAULT_CLR_ALL	(ZX_TO_FAULT_CLR_BIT | SC_CLR_BIT | \
> +			 AUTO_RES_ERR_CLR_BIT | HPWR_RDY_FAULT_CLR_BIT)
> +#define HAP_CFG_RAMP_DN_CFG2_REG	0x86
> +#define  AUTORES_PRE_HIZ_DLY_10US	1
> +
> +/* HAP_PTN register offsets, bit fields, value constants */
> +#define HAP_PTN_REVISION2_REG		0x01
> +#define HAP_PTN_FIFO_DIN_0_REG		0x20
> +#define HAP_PTN_FIFO_PLAY_RATE_REG	0x24
> +#define  FIFO_PLAY_RATE_MASK		GENMASK(3, 0)
> +#define HAP_PTN_DIRECT_PLAY_REG		0x26
> +#define HAP_PTN_FIFO_EMPTY_CFG_REG	0x2A
> +#define  FIFO_THRESH_LSB		64
> +#define HAP_PTN_FIFO_DIN_1B_REG		0x2C
> +#define HAP_PTN_MEM_OP_ACCESS_REG	0x2D
> +#define  MEM_FLUSH_RELOAD_BIT		BIT(0)
> +#define HAP_PTN_MMAP_FIFO_REG		0xA0
> +#define  MMAP_FIFO_EXIST_BIT		BIT(7)
> +#define  MMAP_FIFO_LEN_MASK		GENMASK(6, 0)
> +#define HAP_PTN_PATX_PLAY_CFG_REG	0xA2
> +
> +#define HAP530_MEM_TOTAL_BYTES		8192
> +#define FIFO_EMPTY_THRESH		280
> +#define FIFO_INIT_FILL			320
> +
> +#define HAPTICS_AUTOSUSPEND_MS		1000
> +
> +/*
> + * FF_CUSTOM data layout (custom_data[] of type s16):
> + *   [0] = play rate (PLAY_RATE_*)
> + *   [1] = vmax in mV (0 = use device default from qcom,vmax-microvolt)
> + *   [2..N-1] = signed 8-bit PCM samples packed one per s16 (lower byte used)
> + */
> +#define CUSTOM_DATA_RATE_IDX		0
> +#define CUSTOM_DATA_VMAX_IDX		1
> +#define CUSTOM_DATA_SAMPLE_START	2
> +#define CUSTOM_DATA_MAX_LEN		(48 * 1024)
> +
> +#define HAPTICS_MAX_EFFECTS		8
> +
> +enum qcom_haptics_mode {
> +	HAPTICS_MODE_NONE,
> +	HAPTICS_DIRECT_PLAY,
> +	HAPTICS_FIFO,
> +};
> +
> +enum qcom_haptics_play_rate {
> +	PLAY_RATE_T_LRA       = 0,
> +	PLAY_RATE_T_LRA_DIV_2 = 1,
> +	PLAY_RATE_T_LRA_DIV_4 = 2,
> +	PLAY_RATE_T_LRA_DIV_8 = 3,
> +	PLAY_RATE_T_LRA_X_2   = 4,
> +	PLAY_RATE_T_LRA_X_4   = 5,
> +	PLAY_RATE_T_LRA_X_8   = 6,
> +	PLAY_RATE_RESERVED    = 7,
> +	PLAY_RATE_F_8KHZ      = 8,
> +	PLAY_RATE_F_16KHZ     = 9,
> +	PLAY_RATE_F_24KHZ     = 10,
> +	PLAY_RATE_F_32KHZ     = 11,
> +	PLAY_RATE_F_44P1KHZ   = 12,
> +	PLAY_RATE_F_48KHZ     = 13,
> +	PLAY_RATE_MAX	      = PLAY_RATE_F_48KHZ,
> +};
> +
> +/**
> + * struct qcom_haptics_effect: A haptics effect
> + * @mode:	haptics HW play mode
> + * @vmax_mv:	peak voltage of the haptics output waveform
> + * @length_us:	vibration play duration
> + * @amplitude:	DIRECT_PLAY mode output waveform amplitude
> + * @play_rate:	FIFO mode play rate
> + * @fifo_data:	8-bit data samples consumed in FIFO mode
> + * @data_len:	length of the FIFO data samples
> + */
> +struct qcom_haptics_effect {
> +	enum qcom_haptics_mode mode;
> +	u32 vmax_mv;
> +	u32 length_us;
> +
> +	u8 amplitude;
> +
> +	enum qcom_haptics_play_rate play_rate;
> +	s8 *fifo_data;
> +	u32 data_len;
> +};
> +
> +/**
> + * struct haptics_play_req: A haptics play request
> + * @node:	list node of the request
> + * @effect_id:	effect index of the request
> + * @play:	flag of starting or stopping the play
> + */
> +struct haptics_play_req {
> +	struct list_head node;
> +	int effect_id;
> +	bool play;
> +};
> +
> +/**
> + * struct qcom_haptics
> + * @dev:          underlying SPMI device
> + * @regmap:       regmap for SPMI register access
> + * @input:        input device exposing the FF interface
> + * @cfg_base:     base address of the CFG peripheral
> + * @ptn_base:     base address of the PTN peripheral
> + * @t_lra_us:     LRA resonance period in microseconds
> + * @vmax_mv:      maximum actuator drive voltage in millivolts
> + * @fifo_len:     programmed HW FIFO depth in bytes
> + * @gain:         playback gain scaler
> + * @play_work:    delayed work that plays the queued requests
> + * @play_lock:    mutex lock to serialize playbacks
> + * @play_queue_lock: spinlock protecting @play_queue
> + * @play_queue:   The list of pending start/stop requests
> + * @active_effect_id: index into @effects[] currently under play
> + * @active_mode:  mode of the effect currently armed in hardware
> + * @fifo_empty_irq: IRQ number for the FIFO-empty interrupt
> + * @pm_ref_held:  true while a pm_runtime_get is held
> + * @irq_enabled:  true if fifo_empty_irq is enabled
> + * @fifo_lock:    mutex protecting the FIFO streaming data
> + * @fifo_data:    pointer of the data buffer for FIFO streaming
> + * @data_len:     length of the data buffer for current effect
> + * @data_written: number of samples written to the hardware FIFO
> + * @effects:      table of the effects
> + */
> +struct qcom_haptics {
> +	struct device *dev;
> +	struct regmap *regmap;
> +	struct input_dev *input;
> +
> +	u32 cfg_base;
> +	u32 ptn_base;
> +	u32 t_lra_us;
> +	u32 vmax_mv;
> +	u32 fifo_len;
> +	atomic_t gain;
> +
> +	struct delayed_work play_work;
> +	struct mutex play_lock; /* mutex used to serialize playbacks */
> +
> +	spinlock_t play_queue_lock; /* protects play_queue */
> +	struct list_head play_queue;
> +
> +	int active_effect_id;
> +	enum qcom_haptics_mode active_mode;
> +
> +	int fifo_empty_irq;
> +	bool pm_ref_held;
> +	bool irq_enabled;
> +
> +	struct mutex fifo_lock; /* protect the FIFO data during play */
> +	const s8 *fifo_data;
> +	u32 data_len;
> +	u32 data_written;
> +
> +	struct qcom_haptics_effect effects[HAPTICS_MAX_EFFECTS];
> +};
> +
> +static int cfg_write(struct qcom_haptics *h, u32 off, u32 val)
> +{
> +	return regmap_write(h->regmap, h->cfg_base + off, val);
> +}
> +
> +static int cfg_update_bits(struct qcom_haptics *h, u32 off, u32 mask, u32 val)
> +{
> +	return regmap_update_bits(h->regmap, h->cfg_base + off, mask, val);
> +}
> +
> +static int ptn_write(struct qcom_haptics *h, u32 off, u32 val)
> +{
> +	return regmap_write(h->regmap, h->ptn_base + off, val);
> +}
> +
> +static int ptn_update_bits(struct qcom_haptics *h, u32 off, u32 mask, u32 val)
> +{
> +	return regmap_update_bits(h->regmap, h->ptn_base + off, mask, val);
> +}
> +
> +static int ptn_bulk_write(struct qcom_haptics *h, u32 off,
> +			  const void *buf, size_t count)
> +{
> +	return regmap_bulk_write(h->regmap, h->ptn_base + off, buf, count);
> +}
> +
> +static int haptics_clear_faults(struct qcom_haptics *h)
> +{
> +	return cfg_write(h, HAP_CFG_FAULT_CLR_REG, FAULT_CLR_ALL);
> +}
> +
> +static int haptics_set_vmax(struct qcom_haptics *h, u32 vmax_mv)
> +{
> +	return cfg_write(h, HAP_CFG_VMAX_REG, vmax_mv / VMAX_STEP_MV);
> +}
> +
> +static int haptics_config_lra_period(struct qcom_haptics *h)
> +{
> +	u32 tmp = h->t_lra_us / TLRA_STEP_US;
> +	int ret;

Please use "error" or "err" for such variables that hold error codes.

> +
> +	ret = cfg_write(h, HAP_CFG_TLRA_OL_HIGH_REG, (tmp >> 8) & TLRA_OL_MSB_MASK);
> +	if (ret)
> +		return ret;
> +
> +	return cfg_write(h, HAP_CFG_TLRA_OL_LOW_REG, tmp & 0xFF);

Explicit error handling and "return 0;" in cases where there are
multiple failure points.

> +}
> +
> +static int haptics_enable_module(struct qcom_haptics *h, bool enable)
> +{
> +	return cfg_update_bits(h, HAP_CFG_EN_CTL_REG, HAPTICS_EN_BIT,
> +			       enable ? HAPTICS_EN_BIT : 0);
> +}
> +
> +static int haptics_configure_autores(struct qcom_haptics *h)
> +{
> +	int ret;
> +
> +	/* AUTORES_CFG: enable, 10-cycle delay, 25% error window */
> +	ret = cfg_write(h, HAP_CFG_AUTORES_CFG_REG,
> +			AUTORES_EN_BIT |
> +			FIELD_PREP(AUTORES_EN_DLY_MASK, AUTORES_EN_DLY_CYCLES) |
> +			FIELD_PREP(AUTORES_ERR_WIN_MASK, AUTORES_ERR_WIN_25PCT));
> +	if (ret)
> +		return ret;
> +
> +	/* DRV_DUTY: adaptive drive/brake duty cycles at 62.5% */
> +	ret = cfg_write(h, HAP_CFG_DRV_DUTY_CFG_REG,
> +			ADT_DRV_DUTY_EN_BIT | ADT_BRK_DUTY_EN_BIT |
> +			FIELD_PREP(DRV_DUTY_MASK, AUTORES_DRV_DUTY_62P5) |
> +			FIELD_PREP(BRK_DUTY_MASK, AUTORES_BRK_DUTY_62P5));
> +	if (ret)
> +		return ret;
> +
> +	/* Pre-HIZ delay: 10 µs */
> +	ret = cfg_write(h, HAP_CFG_RAMP_DN_CFG2_REG, AUTORES_PRE_HIZ_DLY_10US);
> +	if (ret)
> +		return ret;
> +
> +	/* Zero-cross window: debounce 3, no hysteresis, height 2 */
> +	return cfg_write(h, HAP_CFG_ZX_WIND_CFG_REG,
> +			 FIELD_PREP(ZX_DEBOUNCE_MASK, AUTORES_ZX_DEBOUNCE) |
> +			 FIELD_PREP(ZX_WIN_HEIGHT_MASK, AUTORES_ZX_WIN_HEIGHT));
> +}
> +
> +static int haptics_write_fifo_chunk(struct qcom_haptics *h,
> +				    const s8 *data, u32 len)
> +{
> +	u32 bulk_len = ALIGN_DOWN(len, 4);
> +	int i, ret;
> +
> +	/*
> +	 * FIFO data writing supports both 4-byte bulk writes using registers
> +	 * [HAP_PTN_FIFO_DIN_0_REG ... HAP_PTN_FIFO_DIN_3_REG], and 1-byte writes
> +	 * using the HAP_PTN_FIFO_DIN_1B_REG register. The 4-byte bulk write is more
> +	 * efficient, so use 4-byte writes for the initial 4-byte aligned data,
> +	 * and 1-byte writes for any trailing remainder.
> +	 */
> +	for (i = 0; i < bulk_len; i += 4) {
> +		ret = ptn_bulk_write(h, HAP_PTN_FIFO_DIN_0_REG, &data[i], 4);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	for (; i < len; i++) {
> +		ret = ptn_write(h, HAP_PTN_FIFO_DIN_1B_REG, (u8)data[i]);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int haptics_configure_fifo_mmap(struct qcom_haptics *h)
> +{
> +	u32 fifo_len, fifo_units;
> +
> +	/* Config all memory space for FIFO usage for now */
> +	fifo_len = HAP530_MEM_TOTAL_BYTES;
> +	fifo_len = ALIGN_DOWN(fifo_len, 64);
> +	fifo_units = fifo_len / 64;
> +	h->fifo_len = fifo_len;
> +
> +	return ptn_write(h, HAP_PTN_MMAP_FIFO_REG,
> +			 MMAP_FIFO_EXIST_BIT |
> +			 FIELD_PREP(MMAP_FIFO_LEN_MASK, fifo_units - 1));
> +}
> +
> +static u32 haptics_gain_scaled_vmax(struct qcom_haptics *h, u32 vmax_mv)
> +{
> +	u16 gain = atomic_read(&h->gain);
> +	u32 v = mult_frac(vmax_mv, gain, 0xFFFF);
> +
> +	return max_t(u32, v, VMAX_STEP_MV);
> +}
> +
> +static void haptics_fifo_irq_enable(struct qcom_haptics *h, bool enable)
> +{
> +	if (h->irq_enabled == enable)
> +		return;

Should t you know if given code runs with interrupts disabled or
enabled? I believe this tracking and the wrapper should be removed.

> +
> +	if (enable)
> +		enable_irq(h->fifo_empty_irq);
> +	else
> +		disable_irq(h->fifo_empty_irq);
> +
> +	h->irq_enabled = enable;
> +}
> +
> +static int haptics_enqueue_play_req(struct qcom_haptics *h, int effect_id, bool play)
> +{
> +	struct haptics_play_req *req;
> +
> +	guard(spinlock_irqsave)(&h->play_queue_lock);
> +
> +	/*
> +	 * Coalesce with an already queued request for
> +	 * the same effect instead of appending.
> +	 */
> +	list_for_each_entry(req, &h->play_queue, node) {
> +		if (req->effect_id == effect_id) {
> +			req->play = play;
> +			return 0;
> +		}
> +	}
> +
> +	req = kmalloc_obj(*req, GFP_ATOMIC);
> +	if (!req)
> +		return -ENOMEM;
> +
> +	req->effect_id = effect_id;
> +	req->play = play;
> +
> +	list_add_tail(&req->node, &h->play_queue);
> +
> +	return 0;
> +}
> +
> +static struct haptics_play_req *haptics_dequeue_play_req(struct qcom_haptics *h)
> +{
> +	struct haptics_play_req *req = NULL;
> +
> +	guard(spinlock_irqsave)(&h->play_queue_lock);
> +
> +	if (!list_empty(&h->play_queue)) {
> +		req = list_first_entry(&h->play_queue, struct haptics_play_req, node);
> +		list_del(&req->node);
> +	}
> +
> +	return req;
> +}
> +
> +static bool haptics_queue_pending(struct qcom_haptics *h)
> +{
> +	guard(spinlock_irqsave)(&h->play_queue_lock);
> +
> +	return !list_empty(&h->play_queue);

I strongly dislike this kind of functions since their result is
obsolete the moment they return. Sometimes it is OK, but usually it
isn't. In this driver I think it is fine, but I would much rather inline
this into the caller and added comment. We can also schedule work
holding this spinlock I think...

> +}
> +
> +static void haptics_queue_remove_effect(struct qcom_haptics *h, int effect_id)
> +{
> +	struct haptics_play_req *req, *tmp;
> +
> +	guard(spinlock_irqsave)(&h->play_queue_lock);
> +
> +	list_for_each_entry_safe(req, tmp, &h->play_queue, node) {
> +		if (req->effect_id == effect_id) {
> +			list_del(&req->node);
> +			kfree(req);
> +		}
> +	}
> +}
> +
> +static void haptics_queue_flush(struct qcom_haptics *h)
> +{
> +	struct haptics_play_req *req, *tmp;
> +
> +	guard(spinlock_irqsave)(&h->play_queue_lock);
> +
> +	list_for_each_entry_safe(req, tmp, &h->play_queue, node) {
> +		list_del(&req->node);
> +		kfree(req);
> +	}
> +}
> +
> +static int haptics_start_direct_play(struct qcom_haptics *h, int effect_id)
> +{
> +	struct qcom_haptics_effect *eff = &h->effects[effect_id];
> +	int ret;
> +
> +	ret = haptics_clear_faults(h);
> +	if (ret)
> +		return ret;
> +
> +	/* Enable auto-resonance for DIRECT_PLAY mode */
> +	ret = cfg_update_bits(h, HAP_CFG_AUTORES_CFG_REG,
> +			      AUTORES_EN_BIT, AUTORES_EN_BIT);
> +	if (ret)
> +		return ret;
> +
> +	ret = haptics_set_vmax(h, haptics_gain_scaled_vmax(h, h->vmax_mv));
> +	if (ret)
> +		return ret;
> +
> +	ret = ptn_write(h, HAP_PTN_DIRECT_PLAY_REG, eff->amplitude);
> +	if (ret)
> +		return ret;
> +
> +	return cfg_write(h, HAP_CFG_SPMI_PLAY_REG,
> +			 PLAY_EN_BIT | FIELD_PREP(PAT_SRC_MASK, PAT_SRC_DIRECT_PLAY));
> +}
> +
> +static int haptics_start_fifo(struct qcom_haptics *h, int effect_id)
> +{
> +	struct qcom_haptics_effect *eff = &h->effects[effect_id];
> +	u32 vmax = eff->vmax_mv ? eff->vmax_mv : h->vmax_mv;
> +	u32 init_len;
> +	bool data_done;
> +	int ret;
> +
> +	if (!eff->fifo_data || !eff->data_len)
> +		return -EINVAL;
> +
> +	ret = haptics_clear_faults(h);
> +	if (ret)
> +		return ret;
> +
> +	/* Disable auto-resonance for FIFO mode */
> +	ret = cfg_update_bits(h, HAP_CFG_AUTORES_CFG_REG, AUTORES_EN_BIT, 0);
> +	if (ret)
> +		return ret;
> +
> +	ret = haptics_set_vmax(h, haptics_gain_scaled_vmax(h, vmax));
> +	if (ret)
> +		return ret;
> +
> +	ret = ptn_update_bits(h, HAP_PTN_FIFO_PLAY_RATE_REG,
> +			      FIFO_PLAY_RATE_MASK,
> +			      FIELD_PREP(FIFO_PLAY_RATE_MASK, eff->play_rate));
> +	if (ret)
> +		return ret;
> +
> +	/* Flush FIFO before loading new data */
> +	ret = ptn_write(h, HAP_PTN_MEM_OP_ACCESS_REG, MEM_FLUSH_RELOAD_BIT);
> +	if (ret)
> +		return ret;
> +	ret = ptn_write(h, HAP_PTN_MEM_OP_ACCESS_REG, 0);
> +	if (ret)
> +		return ret;
> +
> +	guard(mutex)(&h->fifo_lock);
> +
> +	/* Write the initial chunk and initialise streaming state */
> +	init_len = min_t(u32, eff->data_len, FIFO_INIT_FILL);
> +	ret = haptics_write_fifo_chunk(h, eff->fifo_data, init_len);
> +	if (ret)
> +		return ret;
> +
> +	h->fifo_data    = eff->fifo_data;
> +	h->data_len     = eff->data_len;
> +	h->data_written = init_len;
> +
> +	/*
> +	 * Set empty threshold.  When threshold > 0 the hardware fires the
> +	 * FIFO-empty interrupt when occupancy drops below the threshold,
> +	 * allowing the driver to refill.
> +	 */
> +	data_done = (h->data_written >= h->data_len);
> +	if (!data_done) {
> +		ret = ptn_write(h, HAP_PTN_FIFO_EMPTY_CFG_REG,
> +				FIFO_EMPTY_THRESH / FIFO_THRESH_LSB);
> +		if (ret) {
> +			dev_err(h->dev, "set FIFO empty threshold failed, ret=%d\n", ret);
> +			h->fifo_data = NULL;
> +			return ret;
> +		}
> +
> +		haptics_fifo_irq_enable(h, true);
> +	}
> +
> +	ret = cfg_write(h, HAP_CFG_SPMI_PLAY_REG,
> +			 PLAY_EN_BIT | FIELD_PREP(PAT_SRC_MASK, PAT_SRC_FIFO));
> +	if (ret) {
> +		dev_err(h->dev, "trigger FIFO play failed, ret=%d\n", ret);
> +		ptn_write(h, HAP_PTN_FIFO_EMPTY_CFG_REG, 0);
> +		/*
> +		 * HW play never started since this SPMI write itself failed,
> +		 * and the FIFO empty IRQ has never fired, so disabling the
> +		 * IRQ synchronously here can't deadlock against 'fifo_lock'.
> +		 */
> +		haptics_fifo_irq_enable(h, false);
> +		h->fifo_data = NULL;
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +/*
> + * haptics_fifo_empty_irq: Threaded IRQ handler for the FIFO-empty interrupt.
> + *
> + * While a FIFO play is in progress the hardware fires this interrupt when
> + * the number of samples in the FIFO drops below the programmed threshold.
> + * The handler refills the FIFO from the effect's data buffer.  When all
> + * samples have been written the threshold is set to zero. The HW would
> + * stop the play automatically after all of the samples in FIFO memory are
> + * played out.
> + */
> +static irqreturn_t haptics_fifo_empty_irq(int irq, void *dev_id)
> +{
> +	struct qcom_haptics *h = dev_id;
> +	u32 sts, to_write;
> +	int ret;
> +
> +	ret = regmap_read(h->regmap,
> +			  h->cfg_base + HAP_CFG_INT_RT_STS_REG, &sts);
> +	if (ret || !(sts & FIFO_EMPTY_BIT))
> +		return IRQ_HANDLED;
> +
> +	guard(mutex)(&h->fifo_lock);
> +
> +	if (!h->fifo_data)
> +		return IRQ_HANDLED;
> +
> +	/* Refill: write the next chunk */
> +	to_write = min_t(u32, h->data_len - h->data_written,
> +			 h->fifo_len - FIFO_EMPTY_THRESH);
> +	ret = haptics_write_fifo_chunk(h, &h->fifo_data[h->data_written], to_write);
> +	if (ret) {
> +		dev_err(h->dev, "refill FIFO samples failed, ret=%d\n", ret);
> +		/*
> +		 * If data refilling is failed,stop the HW play and disable the
> +		 * IRQ to prevent the FIFO empty IRQ being fired continuously.
> +		 */

Is recovery possible after this?

> +		cfg_write(h, HAP_CFG_SPMI_PLAY_REG, 0);
> +		disable_irq_nosync(h->fifo_empty_irq);
> +		h->irq_enabled = false;
> +		return IRQ_HANDLED;
> +	}
> +
> +	h->data_written += to_write;
> +
> +	/* Disable the interrupt after all the data is queued */
> +	if (h->data_written >= h->data_len)
> +		ptn_write(h, HAP_PTN_FIFO_EMPTY_CFG_REG, 0);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +/*
> + * haptics_stop_locked: stop play in HW and put runtime PM
> + * @h:	haptics device
> + * @put_noidle:	a flag to put noidle
> + *
> + * Stop HW play, clear the FIFO data if the active effect was FIFO-mode, and
> + * put runtime PM into either noidle or autosuspend based on put_noidle flag.
> + *
> + * Must be called with play_lock held.

Maybe add lockdep_assert_held() instead of comments/naming?

> + */
> +static void haptics_stop_locked(struct qcom_haptics *h, bool put_noidle)
> +{
> +	cfg_write(h, HAP_CFG_SPMI_PLAY_REG, 0);
> +
> +	if (h->active_mode == HAPTICS_FIFO) {
> +		ptn_write(h, HAP_PTN_FIFO_EMPTY_CFG_REG, 0);
> +		haptics_fifo_irq_enable(h, false);
> +		scoped_guard(mutex, &h->fifo_lock) {
> +			h->fifo_data = NULL;
> +		}
> +	}
> +
> +	h->active_effect_id = -1;
> +	h->active_mode = HAPTICS_MODE_NONE;
> +
> +	if (h->pm_ref_held) {
> +		if (put_noidle)
> +			pm_runtime_put_noidle(h->dev);
> +		else
> +			pm_runtime_put_autosuspend(h->dev);
> +
> +		h->pm_ref_held = false;
> +	}
> +}
> +
> +/*
> + * haptics_start_locked: start to play an effect
> + * @h:	haptics device
> + * @effect_id:	the index of the effect
> + *
> + * If an effect is currently active, stop it 1st. Acquires a PM ref
> + * if not already held, and then trigger the play based on the
> + * play mode. Update active_effect_id/active_mode on success.
> + *
> + * Must be called with play_lock held.
> + */
> +static int haptics_start_locked(struct qcom_haptics *h, int effect_id)
> +{
> +	int ret;
> +
> +	if (h->active_effect_id != -1)
> +		haptics_stop_locked(h, false);
> +
> +	if (!h->pm_ref_held) {
> +		ret = pm_runtime_resume_and_get(h->dev);
> +		if (ret < 0) {
> +			dev_err(h->dev, "failed to resume device: %d\n", ret);
> +			return ret;
> +		}
> +
> +		h->pm_ref_held = true;
> +	}
> +
> +	switch (h->effects[effect_id].mode) {
> +	case HAPTICS_DIRECT_PLAY:
> +		ret = haptics_start_direct_play(h, effect_id);
> +		break;
> +	case HAPTICS_FIFO:
> +		ret = haptics_start_fifo(h, effect_id);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +
> +	if (ret) {
> +		dev_err(h->dev, "failed to start effect %d: %d\n", effect_id, ret);
> +		if (h->pm_ref_held) {
> +			pm_runtime_put_autosuspend(h->dev);
> +			h->pm_ref_held = false;
> +		}
> +
> +		return ret;
> +	}
> +
> +	h->active_effect_id = effect_id;
> +	h->active_mode = h->effects[effect_id].mode;
> +
> +	return 0;
> +}
> +
> +static void haptics_play_work(struct work_struct *work)
> +{
> +	struct qcom_haptics *h = container_of(to_delayed_work(work),
> +					      struct qcom_haptics, play_work);
> +	struct haptics_play_req *req = haptics_dequeue_play_req(h);
> +	bool rearmed = false;
> +	u32 length_us;
> +	int ret;
> +
> +	guard(mutex)(&h->play_lock);
> +
> +	/* No valid request available */
> +	if (req == NULL)

	if (!req)

> +		return;
> +
> +	if (req->play) {
> +		ret = haptics_start_locked(h, req->effect_id);
> +		if (ret) {
> +			dev_err(h->dev, "play haptics failed, ret=%d\n", ret);
> +		} else {
> +			/*
> +			 * Re-arm the work to stop the play or advance
> +			 * to next play after the play duration
> +			 */
> +			length_us = h->effects[req->effect_id].length_us;
> +			if (length_us) {
> +				schedule_delayed_work(&h->play_work,
> +						      usecs_to_jiffies(length_us));
> +				rearmed = true;
> +			}
> +		}
> +	} else {
> +		if (req->effect_id != h->active_effect_id)
> +			dev_warn(h->dev, "effect %d is not under playing\n", req->effect_id);
> +		else
> +			haptics_stop_locked(h, false);
> +	}
> +
> +	kfree(req);
> +
> +	/*
> +	 * Handle the remaining requests if doesn't need to wait
> +	 */
> +	if (!rearmed && haptics_queue_pending(h))
> +		schedule_delayed_work(&h->play_work, 0);
> +}
> +
> +static void haptics_clear_effect(struct qcom_haptics *h,
> +				 struct qcom_haptics_effect *effect)
> +{
> +	guard(mutex)(&h->fifo_lock);
> +
> +	if (h->fifo_data == effect->fifo_data)
> +		h->fifo_data = NULL;
> +
> +	kvfree(effect->fifo_data);
> +	effect->fifo_data = NULL;
> +	effect->data_len  = 0;
> +}
> +
> +/*
> + * haptics_fifo_length_us: Calculate the play duration of a FIFO effect.
> + * @h:	haptics device pointer
> + * @rate: FIFO data play rate
> + * @data_len: FFO data length
> + *
> + * Each FIFO sample is played out over one play-rate period, so the total
> + * duration is the number of samples times that period:
> + *
> + *   length_us = (clk_base * data_len * multiplier) / divider
> + *
> + * For T_LRA-based rates the period derives from the LRA resonance period
> + * (h->t_lra_us): DIV_2/4/8 shorten it, X_2/4/8 lengthen it.  For the
> + * kHz-based rates the period is 1000 us / freq_khz.
> + */
> +static u32 haptics_fifo_length_us(struct qcom_haptics *h,
> +				  enum qcom_haptics_play_rate rate,
> +				  u32 data_len)
> +{
> +	u32 clk_base = 1000, multiplier = 1, divider = 1;
> +
> +	switch (rate) {
> +	case PLAY_RATE_T_LRA:
> +		clk_base = h->t_lra_us;
> +		break;
> +	case PLAY_RATE_T_LRA_DIV_2:
> +		clk_base = h->t_lra_us;
> +		divider = 2;
> +		break;
> +	case PLAY_RATE_T_LRA_DIV_4:
> +		clk_base = h->t_lra_us;
> +		divider = 4;
> +		break;
> +	case PLAY_RATE_T_LRA_DIV_8:
> +		clk_base = h->t_lra_us;
> +		divider = 8;
> +		break;
> +	case PLAY_RATE_T_LRA_X_2:
> +		clk_base = h->t_lra_us;
> +		multiplier = 2;
> +		break;
> +	case PLAY_RATE_T_LRA_X_4:
> +		clk_base = h->t_lra_us;
> +		multiplier = 4;
> +		break;
> +	case PLAY_RATE_T_LRA_X_8:
> +		clk_base = h->t_lra_us;
> +		multiplier = 8;
> +		break;
> +	case PLAY_RATE_F_8KHZ:
> +		divider = 8;
> +		break;
> +	case PLAY_RATE_F_16KHZ:
> +		divider = 16;
> +		break;
> +	case PLAY_RATE_F_24KHZ:
> +		divider = 24;
> +		break;
> +	case PLAY_RATE_F_32KHZ:
> +		divider = 32;
> +		break;
> +	case PLAY_RATE_F_44P1KHZ:
> +		clk_base *= 10;
> +		divider = 441;
> +		break;
> +	case PLAY_RATE_F_48KHZ:
> +		divider = 48;
> +		break;
> +	default:
> +		/* Unexpected rate: fall back to the resonance period. */
> +		clk_base = h->t_lra_us;
> +		break;
> +	}
> +
> +	return div_u64((u64)clk_base * data_len * multiplier, divider);
> +}
> +
> +static int haptics_upload_effect(struct input_dev *dev,
> +				 struct ff_effect *effect,
> +				 struct ff_effect *old)
> +{
> +	struct qcom_haptics *h = input_get_drvdata(dev);
> +	struct qcom_haptics_effect *priv;
> +	int id = effect->id;
> +	u32 data_len, level;
> +	s8 *fifo;
> +
> +	s16 *buf __free(kvfree) = NULL;
> +
> +	guard(mutex)(&h->play_lock);
> +
> +	if (id < 0 || id >= HAPTICS_MAX_EFFECTS)
> +		return -EINVAL;
> +
> +	if (id == h->active_effect_id) {
> +		dev_err(h->dev, "effect %d is under playing\n", id);
> +		return -EBUSY;
> +	}
> +
> +	priv = &h->effects[id];
> +
> +	switch (effect->type) {
> +	case FF_CONSTANT:
> +		haptics_clear_effect(h, priv);
> +		level = effect->u.constant.level <= 0 ? 0 : effect->u.constant.level;
> +		priv->amplitude = (u8)mult_frac(level, 255, 0x7FFF);
> +		priv->length_us = effect->replay.length * USEC_PER_MSEC;
> +		priv->mode = HAPTICS_DIRECT_PLAY;
> +		return 0;
> +
> +	case FF_PERIODIC:
> +		if (effect->u.periodic.waveform != FF_CUSTOM)
> +			return -EINVAL;
> +		/*
> +		 * Minimum 3 elements: play-rate code + vmax + at least one sample.
> +		 * Limit the maximum data length to ~48K so that it can at least
> +		 * handle ~1s vibration at the fast (48K) play rate.
> +		 */
> +		if (effect->u.periodic.custom_len < 3 ||
> +		    effect->u.periodic.custom_len > CUSTOM_DATA_MAX_LEN + 2)
> +			return -EINVAL;
> +
> +		buf = vmemdup_array_user(effect->u.periodic.custom_data,
> +					effect->u.periodic.custom_len,
> +					sizeof(s16));
> +		if (IS_ERR(buf))
> +			return PTR_ERR(no_free_ptr(buf));
> +
> +		if (buf[CUSTOM_DATA_RATE_IDX] < 0 ||
> +		    buf[CUSTOM_DATA_RATE_IDX] > PLAY_RATE_MAX ||
> +		    buf[CUSTOM_DATA_RATE_IDX] == PLAY_RATE_RESERVED)
> +			return -EINVAL;
> +
> +		data_len = effect->u.periodic.custom_len - CUSTOM_DATA_SAMPLE_START;
> +
> +		fifo = kvmalloc(data_len, GFP_KERNEL);
> +		if (!fifo)
> +			return -ENOMEM;
> +
> +		/* Pack: one s8 sample per s16 slot (lower byte) */
> +		for (int i = 0; i < data_len; i++)
> +			fifo[i] = (s8)buf[CUSTOM_DATA_SAMPLE_START + i];
> +
> +		haptics_clear_effect(h, priv);
> +
> +		scoped_guard(mutex, &h->fifo_lock) {
> +			priv->fifo_data = fifo;
> +			priv->data_len = data_len;
> +		}
> +
> +		priv->play_rate = (u8)buf[CUSTOM_DATA_RATE_IDX];
> +		priv->vmax_mv   = (u32)clamp_val(buf[CUSTOM_DATA_VMAX_IDX], 0, VMAX_MV_MAX);
> +		priv->length_us = haptics_fifo_length_us(h, priv->play_rate, data_len);
> +		priv->mode = HAPTICS_FIFO;
> +
> +		return 0;
> +
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int haptics_playback(struct input_dev *dev, int effect_id, int val)
> +{
> +	struct qcom_haptics *h = input_get_drvdata(dev);
> +	int ret;
> +
> +	ret = haptics_enqueue_play_req(h, effect_id, val > 0);
> +	if (ret)
> +		return ret;
> +
> +	if (val > 0)
> +		/*
> +		 * Queue the play.  If a duration re-arm is already pending this
> +		 * is a no-op, so the new play waits for the current effect to
> +		 * finish before the worker dequeues it.
> +		 */
> +		schedule_delayed_work(&h->play_work, 0);
> +	else
> +		/*
> +		 * Run the worker now, cancelling any pending duration re-arm,
> +		 * so an explicit stop takes effect immediately.
> +		 */
> +		mod_delayed_work(system_percpu_wq, &h->play_work, 0);
> +
> +	return 0;
> +}
> +
> +static int haptics_erase(struct input_dev *dev, int effect_id)
> +{
> +	struct qcom_haptics *h = input_get_drvdata(dev);
> +	struct qcom_haptics_effect *priv = &h->effects[effect_id];
> +
> +	guard(mutex)(&h->play_lock);
> +
> +	haptics_queue_remove_effect(h, effect_id);
> +
> +	if (h->active_effect_id == effect_id)
> +		haptics_stop_locked(h, false);
> +
> +	haptics_clear_effect(h, priv);
> +	priv->mode = HAPTICS_MODE_NONE;
> +
> +	return 0;
> +}
> +
> +static void haptics_set_gain(struct input_dev *dev, u16 gain)
> +{
> +	struct qcom_haptics *h = input_get_drvdata(dev);
> +
> +	atomic_set(&h->gain, gain);

You need to adjust currently played effects here: new gain should take
effect immediately.

> +}
> +
> +static int qcom_haptics_probe(struct platform_device *pdev)
> +{
> +	struct qcom_haptics *h;
> +	struct input_dev *input;
> +	struct ff_device *ff;
> +	u32 regs[2], vmax_uv;
> +	int ret, irq;
> +
> +	h = devm_kzalloc(&pdev->dev, sizeof(*h), GFP_KERNEL);
> +	if (!h)
> +		return -ENOMEM;
> +
> +	h->dev = &pdev->dev;
> +
> +	h->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> +	if (!h->regmap)
> +		return dev_err_probe(h->dev, -ENODEV, "no regmap from parent\n");
> +
> +	ret = device_property_read_u32_array(h->dev, "reg", regs, ARRAY_SIZE(regs));
> +	if (ret)
> +		return dev_err_probe(h->dev, ret, "failed to read 'reg' property\n");
> +
> +	h->cfg_base = regs[0];
> +	h->ptn_base = regs[1];
> +
> +	ret = device_property_read_u32(h->dev, "qcom,lra-period-us", &h->t_lra_us);
> +	if (ret)
> +		return dev_err_probe(h->dev, ret, "missing qcom,lra-period-us\n");
> +
> +	h->t_lra_us = clamp(h->t_lra_us, (u32)TLRA_STEP_US, (u32)TLRA_US_MAX);
> +
> +	ret = device_property_read_u32(h->dev, "qcom,vmax-microvolt", &vmax_uv);
> +	if (ret)
> +		return dev_err_probe(h->dev, ret, "missing qcom,vmax-microvolt\n");
> +
> +	h->vmax_mv = clamp(vmax_uv / 1000, (u32)VMAX_STEP_MV, (u32)VMAX_MV_MAX);
> +
> +	ret = haptics_config_lra_period(h);
> +	if (ret)
> +		return ret;
> +
> +	ret = haptics_configure_autores(h);
> +	if (ret)
> +		return ret;
> +
> +	ret = haptics_set_vmax(h, h->vmax_mv);
> +	if (ret)
> +		return ret;
> +
> +	ret = haptics_configure_fifo_mmap(h);
> +	if (ret)
> +		return ret;
> +
> +	mutex_init(&h->play_lock);
> +	mutex_init(&h->fifo_lock);
> +	spin_lock_init(&h->play_queue_lock);
> +	INIT_LIST_HEAD(&h->play_queue);
> +	INIT_DELAYED_WORK(&h->play_work, haptics_play_work);
> +	atomic_set(&h->gain, 0xFFFF);
> +	h->active_effect_id = -1;
> +
> +	irq = platform_get_irq_byname(pdev, "fifo-empty");
> +	if (irq < 0)
> +		return dev_err_probe(h->dev, irq, "failed to get fifo-empty IRQ\n");
> +
> +	ret = devm_request_threaded_irq(h->dev, irq, NULL,
> +					haptics_fifo_empty_irq,
> +					IRQF_ONESHOT | IRQF_NO_AUTOEN,
> +					"qcom-haptics-fifo-empty", h);
> +	if (ret)
> +		return dev_err_probe(h->dev, ret, "failed to request fifo-empty IRQ\n");
> +
> +	h->fifo_empty_irq = irq;
> +	platform_set_drvdata(pdev, h);
> +
> +	pm_runtime_use_autosuspend(h->dev);
> +	pm_runtime_set_autosuspend_delay(h->dev, HAPTICS_AUTOSUSPEND_MS);
> +	ret = devm_pm_runtime_enable(h->dev);
> +	if (ret)
> +		return dev_err_probe(h->dev, ret, "enable runtime PM failed\n");
> +
> +	input = devm_input_allocate_device(h->dev);
> +	if (!input)
> +		return -ENOMEM;
> +
> +	input->name = "qcom-spmi-haptics";

Set bus type? BUS_HOST?

> +	input_set_drvdata(input, h);
> +	h->input = input;
> +
> +	input_set_capability(input, EV_FF, FF_CONSTANT);
> +	input_set_capability(input, EV_FF, FF_PERIODIC);
> +	input_set_capability(input, EV_FF, FF_CUSTOM);
> +	input_set_capability(input, EV_FF, FF_GAIN);
> +
> +	ret = input_ff_create(input, HAPTICS_MAX_EFFECTS);
> +	if (ret)
> +		return ret;
> +
> +	ff = input->ff;
> +	ff->upload   = haptics_upload_effect;
> +	ff->playback = haptics_playback;
> +	ff->erase    = haptics_erase;
> +	ff->set_gain = haptics_set_gain;
> +
> +	ret = input_register_device(input);
> +	if (ret) {
> +		input_ff_destroy(input);

This is harmless but not needed: FF portion will be freed automatically.

> +		return dev_err_probe(h->dev, ret, "failed to register input device\n");
> +	}
> +
> +	return 0;
> +}
> +
> +static void qcom_haptics_remove(struct platform_device *pdev)
> +{
> +	struct qcom_haptics *h = platform_get_drvdata(pdev);
> +
> +	/*
> +	 * Unregister the input device explicitly at the beginning
> +	 * to avoid the input device being used after the resources
> +	 * are freed.
> +	 */
> +	input_unregister_device(h->input);
> +	disable_delayed_work_sync(&h->play_work);
> +	scoped_guard(mutex, &h->play_lock) {
> +		haptics_queue_flush(h);
> +		haptics_stop_locked(h, true);
> +	}
> +
> +	haptics_enable_module(h, false);
> +
> +	scoped_guard(mutex, &h->fifo_lock) {
> +		for (int i = 0; i < HAPTICS_MAX_EFFECTS; i++) {
> +			kvfree(h->effects[i].fifo_data);
> +			h->effects[i].fifo_data = NULL;
> +		}
> +	}

Most of this is better suited to close() method of input device.

> +}
> +
> +static int qcom_haptics_runtime_suspend(struct device *dev)
> +{
> +	struct qcom_haptics *h = dev_get_drvdata(dev);
> +
> +	return haptics_enable_module(h, false);
> +}
> +
> +static int qcom_haptics_runtime_resume(struct device *dev)
> +{
> +	struct qcom_haptics *h = dev_get_drvdata(dev);
> +
> +	return haptics_enable_module(h, true);
> +}
> +
> +static int qcom_haptics_suspend(struct device *dev)
> +{
> +	struct qcom_haptics *h = dev_get_drvdata(dev);
> +	int ret;
> +
> +	disable_delayed_work_sync(&h->play_work);
> +	scoped_guard(mutex, &h->play_lock) {
> +		haptics_queue_flush(h);
> +		haptics_stop_locked(h, true);
> +	}
> +
> +	ret = pm_runtime_force_suspend(dev);
> +	if (ret)
> +		enable_delayed_work(&h->play_work);
> +
> +	return ret;
> +}
> +
> +static int qcom_haptics_resume(struct device *dev)
> +{
> +	struct qcom_haptics *h = dev_get_drvdata(dev);
> +
> +	enable_delayed_work(&h->play_work);
> +
> +	return pm_runtime_force_resume(dev);
> +}
> +
> +static const struct dev_pm_ops qcom_haptics_pm_ops = {
> +	SYSTEM_SLEEP_PM_OPS(qcom_haptics_suspend, qcom_haptics_resume)
> +	RUNTIME_PM_OPS(qcom_haptics_runtime_suspend, qcom_haptics_runtime_resume,
> +		       NULL)
> +};
> +
> +static const struct of_device_id qcom_haptics_of_match[] = {
> +	{ .compatible = "qcom,spmi-haptics" },
> +	{}

	{ }
> +};
> +MODULE_DEVICE_TABLE(of, qcom_haptics_of_match);
> +
> +static struct platform_driver qcom_haptics_driver = {
> +	.probe  = qcom_haptics_probe,
> +	.remove = qcom_haptics_remove,
> +	.driver = {
> +		.name		= "qcom-spmi-haptics",
> +		.of_match_table	= qcom_haptics_of_match,
> +		.pm		= pm_ptr(&qcom_haptics_pm_ops),
> +	},
> +};
> +module_platform_driver(qcom_haptics_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm SPMI PMIC Haptics driver");
> +MODULE_LICENSE("GPL");
> 

Thanks.

-- 
Dmitry

  parent reply	other threads:[~2026-07-17 16:51 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-17  7:28 [PATCH v4 0/3] input: misc: Add an initial driver for haptics inside Qcom PMIH010x PMIC Fenglin Wu
2026-07-17  7:28 ` [PATCH v4 1/3] dt-bindings: input: Add Qualcomm SPMI PMIC haptics Fenglin Wu
2026-07-17  7:29 ` [PATCH v4 2/3] dt-bindings: mfd: qcom,spmi-pmic: Document haptics device Fenglin Wu
2026-07-17  7:29 ` [PATCH v4 3/3] input: misc: Add Qualcomm SPMI PMIC haptics driver Fenglin Wu
2026-07-17  7:42   ` sashiko-bot
2026-07-17 16:51   ` Dmitry Torokhov [this message]
2026-07-17  9:25 ` [PATCH v4 0/3] input: misc: Add an initial driver for haptics inside Qcom PMIH010x PMIC Krzysztof Kozlowski
2026-07-17 18:52 ` Jeff Johnson

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