Re: [PATCH v7 2/2] input: add Qualcomm SPMI haptics driver

From: konrad . dybcio
Date: Mon Oct 17 2022 - 07:42:19 EST

On 2022-10-15 19:30, Caleb Connolly wrote:
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@xxxxxxxxxxxxx>
---
drivers/input/misc/Kconfig | 15 +
drivers/input/misc/Makefile | 1 +
drivers/input/misc/qcom-pmi8998-haptics.c | 690 ++++++++++++++++++++++
3 files changed, 706 insertions(+)
create mode 100644 drivers/input/misc/qcom-pmi8998-haptics.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index a18ab7358d8f..608a64fa7914 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -186,6 +186,21 @@ config INPUT_PMIC8XXX_PWRKEY
To compile this driver as a module, choose M here: the
module will be called pmic8xxx-pwrkey.

+config INPUT_QCOM_PMI8998_HAPTICS
+ tristate "Qualcomm SPMI HAPTICS"
+ depends on ARCH_QCOM || COMPILE_TEST
+ depends on MFD_PM8XXX || MFD_SPMI_PMIC || COMPILE_TEST
+ select INPUT_FF_MEMLESS
+ help
+ This option enables support for the haptics found in pmi8998 and
+ related PMICs. Based on the ff-memless interface.
+
+ This driver is for hardware too new for the INPUT_PM8XXX_VIBRATOR
+ driver.
+
+ To compile this driver as module, choose M here: the
+ module will be called qcom_pmi8998_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 28dfc444f0a9..039d0a97f2f4 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-$(CONFIG_INPUT_QCOM_PMI8998_HAPTICS)+= qcom-pmi8998-haptics.o
obj-$(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-pmi8998-haptics.c
b/drivers/input/misc/qcom-pmi8998-haptics.c
new file mode 100644
index 000000000000..e9eec2d9de2d
--- /dev/null
+++ b/drivers/input/misc/qcom-pmi8998-haptics.c
@@ -0,0 +1,690 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022, Caleb Connolly <caleb@xxxxxxxxxxxxx>
+ * Qualcomm QPMI haptics driver for pmi8998 and related PMICs.
Did they actually call it QPMI or was it supposed to be SPMI?


+ */
+
+#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/time.h>
+#include <linux/types.h>
+
+// clang-format off
Not sure if that was meant to be here?


+#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
Unless something changed, all comments should be /* C-style */

[...]

+ /*
+ * Configure RATE_CFG1 and RATE_CFG2 registers.
+ * Note: For ERM (unsupported) these registers act as play rate and
+ * for LRA these represent resonance period
+ */
+ play_rate = haptics->play_wave_rate / HAP_RATE_CFG_STEP_US;
+ val = FIELD_PREP(HAP_RATE_CFG1_MASK, play_rate);
+ ret = regmap_update_bits(haptics->regmap,
+ haptics->base + HAP_RATE_CFG1_REG,
+ HAP_RATE_CFG1_MASK, val);
+ val = FIELD_PREP(HAP_RATE_CFG2_MASK, play_rate >> 8);
+ ret = ret ?:
IMO the ternary operator here is really forced.. maybe an 'if' would be
more readable


+ regmap_update_bits(haptics->regmap,
+ haptics->base + HAP_RATE_CFG2_REG,
+ HAP_RATE_CFG1_MASK, val);
+ if (ret)
+ return ret;
+
+ ret = haptics_write_brake_pattern(haptics, default_brake_pattern);
+ if (ret)
+ return ret;
+
+ /* Currently this is the only supported play mode */
+ if (haptics->play_mode == HAP_PLAY_BUFFER) {
+ /* zero repeats and zero sample repeats */
+ val = FIELD_PREP(WF_REPEAT_MASK, 0) |
+ FIELD_PREP(WF_S_REPEAT_MASK, 0);
+ ret = regmap_update_bits(haptics->regmap,
+ haptics->base + HAP_WF_REPEAT_REG,
+ WF_REPEAT_MASK | WF_S_REPEAT_MASK,
+ val);
+ if (ret)
+ return ret;
+
+ ret = regmap_bulk_write(haptics->regmap,
+ haptics->base + HAP_WF_S1_REG,
+ wave_sample_pattern, HAP_WAVE_SAMP_LEN);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int spmi_haptics_probe(struct platform_device *pdev)
+{
+ struct spmi_haptics *haptics;
+ struct input_dev *input_dev;
+ int ret, irq;
+
+ 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;
+
+ haptics->dev = &pdev->dev;
+
+ platform_set_drvdata(pdev, haptics);
+
+ ret = device_property_read_u32(haptics->dev, "reg", &haptics->base);
+ if (ret)
+ return dev_err_probe(haptics->dev, ret,
+ "Couldn't read base address");
+
+ /* This is the only currently supported configuration, these values
/*
* This is..


+ * are left to allow future additions
+ */
+ haptics->actuator_type = HAP_TYPE_LRA;
+ haptics->play_mode = HAP_PLAY_BUFFER;
+ haptics->wave_shape = HAP_WAVE_SINE;
+ haptics->current_limit = HAP_ILIM_400_MA;
+
+ ret = device_property_read_u32(haptics->dev, "qcom,wave-play-rate-us",
+ &haptics->play_wave_rate);
+ if (ret)
+ return dev_err_probe(haptics->dev, ret,
+ "qcom,wave-play-rate-us is required\n");
+
+ INIT_WORK(&haptics->work, haptics_play_stop_work);
+
+ ret = haptics_init(haptics);
+ if (ret)
+ return ret;
+
+ input_dev = devm_input_allocate_device(&pdev->dev);
+ if (!input_dev)
+ return -ENOMEM;
+
+ input_dev->name = "spmi_haptics";
+ input_dev->id.version = 1;
+ input_dev->close = spmi_haptics_close;
+ input_set_drvdata(input_dev, haptics);
+
+ haptics->input = input_dev;
+
+ /* In the future this should become FF_PERIODIC */
+ input_set_capability(haptics->input, EV_FF, FF_RUMBLE);
+
+ ret = input_ff_create_memless(input_dev, NULL,
+ spmi_haptics_play_effect);
+ if (ret)
+ return dev_err_probe(
+ &pdev->dev, ret,
+ "Couldn't register haptics as EV_FF device\n");
+
+ ret = input_register_device(input_dev);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret,
+ "Couldn't register input device\n");
+
+ /* NOTE: the play IRQ is only used for buffer mode */
+ irq = platform_get_irq_byname(pdev, "play");
+ if (irq < 0) {
+ return dev_err_probe(&pdev->dev, irq,
+ "Unable to get play irq\n");
+ }
+ ret = devm_request_threaded_irq(haptics->dev, irq, NULL,
+ haptics_play_irq, IRQF_ONESHOT,
+ "haptics_play_irq", haptics);
+ if (ret)
+ return dev_err_probe(haptics->dev, ret,
+ "Couldn't request play irq\n");
+
+ irq = platform_get_irq_byname(pdev, "short");
+ if (irq < 0)
+ return dev_err_probe(&pdev->dev, irq,
+ "Unable to get short circut irq\n");
typo: circuit

+ ret = devm_request_threaded_irq(haptics->dev, irq, NULL, haptics_sc_irq,
+ IRQF_ONESHOT, "haptics_short_irq",
+ haptics);
+ if (ret)
+ return dev_err_probe(haptics->dev, ret,
+ "Couldn't request short circuit irq\n");
+
+ mutex_init(&haptics->play_lock);
+
+ return 0;
+}
+
+static int __maybe_unused spmi_haptics_suspend(struct device *dev)
+{
+ struct spmi_haptics *haptics = dev_get_drvdata(dev);
+
+ cancel_work_sync(&haptics->work);
+ haptics_stop_vibrate(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->input);
+
+ 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);
+ haptics_stop_vibrate(haptics);
+}
+
+static const struct of_device_id spmi_haptics_match_table[] = {
+ { .compatible = "qcom,pmi8998-haptics" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, spmi_haptics_match_table);
+
+static struct platform_driver spmi_haptics_driver = {
I have mixed feelings about calling this "SPMI haptics" instead of something like
"QCOM SPMI haptics" with SPMI being used on all kinds of platforms, but ultimately
I don't think it's that much of an issue, the compatible says it all.

Konrad

+ .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");
+MODULE_AUTHOR("Caleb Connolly <caleb@xxxxxxxxxxxxx>");
--
2.38.0