Re: [PATCH 2/2] input: misc: Add support for isa1200 chip

[Mohan Pallaka]

Thanks for review. The new patch with addressed comments is in internal review phase.
I'd post it as soon as it gets cleared internally.

On 3/24/2011 1:19 PM, Dmitry Torokhov wrote:
> Hi,
>
> On Mon, Mar 07, 2011 at 04:39:42PM +0530, Mohan Pallaka wrote:
>> From: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>>
>> isa1200 chip can be used to generate vibrations to indicate
>> silent alerts, providing gaming haptic actions or vibrations
>> in response to touches. It can operate in two modes, pwm
>> generation and pwm input mode. Pwm generation mode requires
>> external clock and pwm input mode needs the pwm signal to be
>> given as input to the chip.
>>
>> This patch has been derived based on Kyungmin Park's haptic
>> framework patches at http://lkml.org/lkml/2009/10/7/50 . Park's
>> isa1200 driver registers to the haptic class, which is also
>> introduced as part of the same patch series, and userspace will
>> operate the vibrator through exported sysfs entries. This version
>> supports only pwm input mode.
>>
>> This derived patch converts the driver from haptic framework to
>> the Linux supported force feeback framework. It also supports the
>> chip operation in both pwm input and generation modes.
> Looks fairly reasonable, a few comments below.
>
>> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>> Signed-off-by: Mohan Pallaka <mpallaka@xxxxxxxxxxxxxx>
>> ---
>>  drivers/input/misc/Kconfig    |   12 ++
>>  drivers/input/misc/Makefile   |    1 +
>>  drivers/input/misc/isa1200.c  |  440 +++++++++++++++++++++++++++++++++++++++++
>>  include/linux/input/isa1200.h |   45 +++++
>>  4 files changed, 498 insertions(+), 0 deletions(-)
>>  create mode 100644 drivers/input/misc/isa1200.c
>>  create mode 100644 include/linux/input/isa1200.h
>>
>> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
>> index b0c6772..6d20b8b 100644
>> --- a/drivers/input/misc/Kconfig
>> +++ b/drivers/input/misc/Kconfig
>> @@ -302,6 +302,18 @@ config HP_SDC_RTC
>>  	  Say Y here if you want to support the built-in real time clock
>>  	  of the HP SDC controller.
>>  
>> +config INPUT_ISA1200
>> +	tristate "ISA1200 haptic support"
>> +	depends on I2C
>> +	select INPUT_FF_MEMLESS
>> +	help
>> +	  ISA1200 is a high performance enhanced haptic chip.
>> +	  Say Y here if you want to support ISA1200 connected via I2C,
>> +	  and select N if you are unsure.
>> +
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called isa1200.
>> +
>>  config INPUT_PCF50633_PMU
>>  	tristate "PCF50633 PMU events"
>>  	depends on MFD_PCF50633
>> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
>> index 9b47971..4570154 100644
>> --- a/drivers/input/misc/Makefile
>> +++ b/drivers/input/misc/Makefile
>> @@ -23,6 +23,7 @@ obj-$(CONFIG_INPUT_CMA3000_I2C)		+= cma3000_d0x_i2c.o
>>  obj-$(CONFIG_INPUT_COBALT_BTNS)		+= cobalt_btns.o
>>  obj-$(CONFIG_INPUT_DM355EVM)		+= dm355evm_keys.o
>>  obj-$(CONFIG_HP_SDC_RTC)		+= hp_sdc_rtc.o
>> +obj-$(CONFIG_INPUT_ISA1200)		+= isa1200.o
>>  obj-$(CONFIG_INPUT_IXP4XX_BEEPER)	+= ixp4xx-beeper.o
>>  obj-$(CONFIG_INPUT_KEYSPAN_REMOTE)	+= keyspan_remote.o
>>  obj-$(CONFIG_INPUT_M68K_BEEP)		+= m68kspkr.o
>> diff --git a/drivers/input/misc/isa1200.c b/drivers/input/misc/isa1200.c
>> new file mode 100644
>> index 0000000..bce96f8
>> --- /dev/null
>> +++ b/drivers/input/misc/isa1200.c
>> @@ -0,0 +1,440 @@
>> +/*
>> + *  Copyright (C) 2009 Samsung Electronics
>> + *  Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>> + *
>> + *  Copyright (c) 2011, Code Aurora Forum. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#define pr_fmt(fmt) "%s: " fmt, __func__
>> +
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/i2c.h>
>> +#include <linux/gpio.h>
>> +#include <linux/workqueue.h>
>> +#include <linux/delay.h>
>> +#include <linux/pwm.h>
>> +#include <linux/input.h>
>> +#include <linux/slab.h>
>> +#include <linux/pm.h>
>> +#include <linux/input/isa1200.h>
>> +
>> +#define ISA1200_HCTRL0			0x30
>> +#define HCTRL0_MODE_CTRL_BIT		(3)
>> +#define HCTRL0_OVERDRIVE_HIGH_BIT	(5)
>> +#define HCTRL0_OVERDRIVE_EN_BIT		(6)
>> +#define HCTRL0_HAP_EN			(7)
>> +#define HCTRL0_RESET			0x01
>> +#define HCTRL1_RESET			0x4B
>> +
>> +#define ISA1200_HCTRL1			0x31
>> +#define HCTRL1_SMART_ENABLE_BIT		(3)
>> +#define HCTRL1_ERM_BIT			(5)
>> +#define HCTRL1_EXT_CLK_ENABLE_BIT	(7)
>> +
>> +#define ISA1200_HCTRL5			0x35
>> +#define HCTRL5_VIB_STRT			0xD5
>> +#define HCTRL5_VIB_STOP			0x6B
>> +
>> +#define DIVIDER_128			(128)
>> +#define DIVIDER_1024			(1024)
>> +#define DIVIDE_SHIFTER_128		(7)
>> +
>> +#define FREQ_22400			(22400)
>> +#define FREQ_172600			(172600)
>> +
>> +#define POR_DELAY_USEC			250
>> +
>> +struct isa1200_chip {
>> +	const struct isa1200_platform_data *pdata;
>> +	struct i2c_client *client;
>> +	struct input_dev *input_device;
>> +	struct pwm_device *pwm;
>> +	unsigned int period_ns;
>> +	unsigned int state;
>> +	struct work_struct work;
>> +};
>> +
>> +static void isa1200_vib_set(struct isa1200_chip *haptic, int enable)
>> +{
>> +	int rc;
>> +
>> +	if (enable) {
>> +		if (haptic->pdata->mode_ctrl == PWM_INPUT_MODE) {
>> +			rc = pwm_config(haptic->pwm,
>> +				(haptic->period_ns * haptic->pdata->duty) / 100,
>> +				haptic->period_ns);
>> +			if (rc < 0)
>> +				pr_err("pwm_config fail\n");
>> +			rc = pwm_enable(haptic->pwm);
>> +			if (rc < 0)
>> +				pr_err("pwm_enable fail\n");
>> +		} else if (haptic->pdata->mode_ctrl == PWM_GEN_MODE) {
>> +			rc = i2c_smbus_write_byte_data(haptic->client,
>> +						ISA1200_HCTRL5,
>> +						HCTRL5_VIB_STRT);
>> +			if (rc < 0)
>> +				pr_err("start vibration fail\n");
>> +		}
>> +	} else {
>> +		if (haptic->pdata->mode_ctrl == PWM_INPUT_MODE)
>> +			pwm_disable(haptic->pwm);
>> +		else if (haptic->pdata->mode_ctrl == PWM_GEN_MODE) {
>> +			rc = i2c_smbus_write_byte_data(haptic->client,
>> +						ISA1200_HCTRL5,
>> +						HCTRL5_VIB_STOP);
>> +			if (rc < 0)
>> +				pr_err("stop vibration fail\n");
>> +		}
>> +	}
>> +}
>> +
>> +static int isa1200_setup(struct i2c_client *client)
>> +{
>> +	struct isa1200_chip *haptic = i2c_get_clientdata(client);
>> +	int value, temp, rc;
>> +
>> +	gpio_set_value_cansleep(haptic->pdata->hap_en_gpio, 0);
>> +	udelay(POR_DELAY_USEC);
>> +	gpio_set_value_cansleep(haptic->pdata->hap_en_gpio, 1);
>> +
>> +	value =	(haptic->pdata->smart_en << HCTRL1_SMART_ENABLE_BIT) |
>> +		(haptic->pdata->is_erm << HCTRL1_ERM_BIT) |
>> +		(haptic->pdata->ext_clk_en << HCTRL1_EXT_CLK_ENABLE_BIT);
>> +
>> +	rc = i2c_smbus_write_byte_data(client, ISA1200_HCTRL1, value);
>> +	if (rc < 0) {
>> +		pr_err("i2c write failure\n");
>> +		return rc;
>> +	}
>> +
>> +	if (haptic->pdata->mode_ctrl == PWM_GEN_MODE) {
>> +		temp = haptic->pdata->pwm_fd.pwm_div;
>> +		if (temp < DIVIDER_128 || temp > DIVIDER_1024 ||
>> +					temp % DIVIDER_128) {
>> +			pr_err("Invalid divider\n");
> Not "divisor" by any chance?
>
>> +			rc = -EINVAL;
>> +			goto reset_hctrl1;
>> +		}
>> +		value = ((temp >> DIVIDE_SHIFTER_128) - 1);
>> +	} else if (haptic->pdata->mode_ctrl == PWM_INPUT_MODE) {
>> +		temp = haptic->pdata->pwm_fd.pwm_freq;
>> +		if (temp < FREQ_22400 || temp > FREQ_172600 ||
>> +					temp % FREQ_22400) {
>> +			pr_err("Invalid frequency\n");
>> +			rc = -EINVAL;
>> +			goto reset_hctrl1;
>> +		}
>> +		value = ((temp / FREQ_22400) - 1);
>> +		haptic->period_ns = NSEC_PER_SEC / temp;
>> +	}
>> +	value |= (haptic->pdata->mode_ctrl << HCTRL0_MODE_CTRL_BIT) |
>> +		(haptic->pdata->overdrive_high << HCTRL0_OVERDRIVE_HIGH_BIT) |
>> +		(haptic->pdata->overdrive_en << HCTRL0_OVERDRIVE_EN_BIT) |
>> +		(haptic->pdata->chip_en << HCTRL0_HAP_EN);
>> +
>> +	rc = i2c_smbus_write_byte_data(client, ISA1200_HCTRL0, value);
>> +	if (rc < 0) {
>> +		pr_err("i2c write failure\n");
>> +		goto reset_hctrl1;
>> +	}
>> +
>> +	return 0;
>> +
>> +reset_hctrl1:
>> +	i2c_smbus_write_byte_data(client, ISA1200_HCTRL1,
>> +				HCTRL1_RESET);
>> +	return rc;
>> +}
>> +
>> +static void isa1200_worker(struct work_struct *work)
>> +{
>> +	struct isa1200_chip *haptic;
>> +
>> +	haptic = container_of(work, struct isa1200_chip, work);
>> +	isa1200_vib_set(haptic, !!haptic->state);
>> +}
>> +
>> +static int isa1200_play_effect(struct input_dev *dev, void *data,
>> +				struct ff_effect *effect)
>> +{
>> +	struct isa1200_chip *haptic = input_get_drvdata(dev);
>> +
>> +	/* support basic vibration */
>> +	haptic->state = effect->u.rumble.strong_magnitude >> 8;
>> +	if (!haptic->state)
>> +		haptic->state = effect->u.rumble.weak_magnitude >> 9;
>> +
>> +	schedule_work(&haptic->work);
>> +	return 0;
>> +}
>> +
>> +#ifdef CONFIG_PM
> Protect with CONFIG_PM_SLEEP, it will save us a warning if only
> CONFIG_PM_RUNTIME is enabled.
>
>> +static int isa1200_suspend(struct device *dev)
>> +{
>> +	struct isa1200_chip *haptic = dev_get_drvdata(dev);
>> +	int rc;
>> +
>> +	cancel_work_sync(&haptic->work);
>> +	/* turn-off current vibration */
>> +	isa1200_vib_set(haptic, 0);
>> +
>> +	if (haptic->pdata->power_on) {
>> +		rc = haptic->pdata->power_on(0);
> ->power_on(false)?
>
> Everywhere, when arguments are bool please take care to supply boolena
> constants.
>
>> +		if (rc) {
>> +			pr_err("power-down failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +	return 0;
>> +}
>> +
>> +static int isa1200_resume(struct device *dev)
>> +{
>> +	struct isa1200_chip *haptic = dev_get_drvdata(dev);
>> +	int rc;
>> +
>> +	if (haptic->pdata->power_on) {
>> +		rc = haptic->pdata->power_on(1);
>> +		if (rc) {
>> +			pr_err("power-up failed\n");
>> +			return rc;
>> +		}
>> +	}
>> +
>> +	isa1200_setup(haptic->client);
>> +	return 0;
>> +}
>> +#else
>> +#define isa1200_suspend		NULL
>> +#define isa1200_resume		NULL
>> +#endif
>> +
>> +static int isa1200_open(struct input_dev *dev)
>> +{
>> +	struct isa1200_chip *haptic = input_get_drvdata(dev);
>> +	int rc;
>> +
>> +	/* device setup */
>> +	if (haptic->pdata->dev_setup) {
>> +		rc = haptic->pdata->dev_setup(true);
>> +		if (rc < 0) {
>> +			pr_err("setup failed!\n");
>> +			return rc;
>> +		}
>> +	}
>> +
>> +	/* power on */
>> +	if (haptic->pdata->power_on) {
>> +		rc = haptic->pdata->power_on(true);
>> +		if (rc < 0) {
>> +			pr_err("power failed\n");
>> +			goto err_setup;
>> +		}
>> +	}
>> +
>> +	/* request gpio */
>> +	rc = gpio_is_valid(haptic->pdata->hap_en_gpio);
>> +	if (rc) {
>> +		rc = gpio_request(haptic->pdata->hap_en_gpio, "haptic_gpio");
>> +		if (rc) {
>> +			pr_err("gpio %d request failed\n",
>> +					haptic->pdata->hap_en_gpio);
>> +			goto err_power_on;
>> +		}
>> +	} else {
>> +		pr_err("Invalid gpio %d\n",
>> +					haptic->pdata->hap_en_gpio);
>> +		goto err_power_on;
>> +	}
>> +
>> +	rc = gpio_direction_output(haptic->pdata->hap_en_gpio, 0);
>> +	if (rc) {
>> +		pr_err("gpio %d set direction failed\n",
>> +					haptic->pdata->hap_en_gpio);
>> +		goto err_gpio_free;
>> +	}
>> +
>> +	/* setup registers */
>> +	rc = isa1200_setup(haptic->client);
>> +	if (rc < 0) {
>> +		pr_err("setup fail %d\n", rc);
>> +		goto err_gpio_free;
>> +	}
>> +
>> +	if (haptic->pdata->mode_ctrl == PWM_INPUT_MODE) {
>> +		haptic->pwm = pwm_request(haptic->pdata->pwm_ch_id,
>> +				haptic->client->driver->id_table->name);
>> +		if (IS_ERR(haptic->pwm)) {
>> +			pr_err("pwm request failed\n");
>> +			rc = PTR_ERR(haptic->pwm);
>> +			goto err_reset_hctrl0;
>> +		}
>> +	}
>> +
>> +	/* init workqeueue */
>> +	INIT_WORK(&haptic->work, isa1200_worker);
> Why here and not in probe?
>
> Actually, all resource acquisition (gpio_request, pwm_request, and so
> forth) should be done in probe(). open() is supposed to bring device
> from low power mode and configure the chip itself.
>
>> +	return 0;
>> +
>> +err_reset_hctrl0:
>> +	i2c_smbus_write_byte_data(haptic->client, ISA1200_HCTRL0,
>> +					HCTRL0_RESET);
>> +err_gpio_free:
>> +	gpio_free(haptic->pdata->hap_en_gpio);
>> +err_power_on:
>> +	if (haptic->pdata->power_on)
>> +		haptic->pdata->power_on(0);
>> +err_setup:
>> +	if (haptic->pdata->dev_setup)
>> +		haptic->pdata->dev_setup(false);
>> +
>> +	return rc;
>> +}
>> +
>> +static void isa1200_close(struct input_dev *dev)
>> +{
>> +	struct isa1200_chip *haptic = input_get_drvdata(dev);
>> +
>> +	/* turn-off current vibration */
>> +	isa1200_vib_set(haptic, 0);
>> +
> Somewhere here should be call to cancel_work_sync() to ensure that play
> work does not outlive us.
>
>> +	if (haptic->pdata->mode_ctrl == PWM_INPUT_MODE)
>> +		pwm_free(haptic->pwm);
>> +
>> +	gpio_free(haptic->pdata->hap_en_gpio);
>> +
>> +	/* reset hardware registers */
>> +	i2c_smbus_write_byte_data(haptic->client, ISA1200_HCTRL0,
>> +				HCTRL0_RESET);
>> +	i2c_smbus_write_byte_data(haptic->client, ISA1200_HCTRL1,
>> +				HCTRL1_RESET);
>> +
>> +	if (haptic->pdata->dev_setup)
>> +		haptic->pdata->dev_setup(false);
>> +
>> +	/* power-off the chip */
>> +	if (haptic->pdata->power_on)
>> +		haptic->pdata->power_on(0);
>> +}
>> +
>> +static int __devinit isa1200_probe(struct i2c_client *client,
>> +			const struct i2c_device_id *id)
>> +{
>> +	struct isa1200_chip *haptic;
>> +	int rc;
>> +
>> +	if (!i2c_check_functionality(client->adapter,
>> +			I2C_FUNC_SMBUS_BYTE_DATA)) {
>> +		pr_err("i2c is not supported\n");
>> +		return -EIO;
>> +	}
>> +
>> +	if (!client->dev.platform_data) {
>> +		pr_err("pdata is not avaiable\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	haptic = kzalloc(sizeof(struct isa1200_chip), GFP_KERNEL);
>> +	if (!haptic) {
>> +		pr_err("no memory\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	haptic->pdata = client->dev.platform_data;
>> +	haptic->client = client;
>> +
>> +	i2c_set_clientdata(client, haptic);
>> +
>> +	haptic->input_device = input_allocate_device();
>> +	if (!haptic->input_device) {
>> +		pr_err("input device alloc failed\n");
>> +		rc = -ENOMEM;
>> +		goto err_mem_alloc;
>> +	}
>> +
>> +	input_set_drvdata(haptic->input_device, haptic);
>> +	haptic->input_device->name = haptic->pdata->name ? :
>> +					"isa1200-ff-memless";
> "isa1200-ff-memless" is quite ugly, why don't you give a nicer name to
> the device? "ISA1200 Haptic device" or something.
>
>> +
>> +	haptic->input_device->dev.parent = &client->dev;
> input_dev->id.bustype = BUS_I2C;
>
>> +
>> +	input_set_capability(haptic->input_device, EV_FF, FF_RUMBLE);
>> +
>> +	haptic->input_device->open = isa1200_open;
>> +	haptic->input_device->close = isa1200_close;
>> +
>> +	rc = input_ff_create_memless(haptic->input_device, NULL,
>> +					isa1200_play_effect);
>> +	if (rc < 0) {
>> +		pr_err("unable to register with ff\n");
>> +		goto err_free_dev;
>> +	}
>> +
>> +	rc = input_register_device(haptic->input_device);
>> +	if (rc < 0) {
>> +		pr_err("unable to register input device\n");
>> +		goto err_ff_destroy;
>> +	}
>> +	return 0;
>> +
>> +err_ff_destroy:
>> +	input_ff_destroy(haptic->input_device);
>> +err_free_dev:
>> +	input_free_device(haptic->input_device);
>> +err_mem_alloc:
>> +	kfree(haptic);
>> +	return rc;
>> +}
>> +
>> +static int __devexit isa1200_remove(struct i2c_client *client)
>> +{
>> +	struct isa1200_chip *haptic = i2c_get_clientdata(client);
>> +
>> +	input_unregister_device(haptic->input_device);
>> +	kfree(haptic);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct i2c_device_id isa1200_id_table[] = {
>> +	{"isa1200", 0},
>> +	{ },
>> +};
>> +MODULE_DEVICE_TABLE(i2c, isa1200_id_table);
>> +
>> +static const struct dev_pm_ops isa1200_pm_ops = {
>> +	.suspend = isa1200_suspend,
>> +	.resume = isa1200_resume,
>> +};
> static SIMPLE_DEV_PM_OPS(isa1200_pm_ops, isa1200_suspend, isa1200_resume);
>
>> +
>> +static struct i2c_driver isa1200_driver = {
>> +	.driver = {
>> +		.name = "isa1200",
>> +		.owner = THIS_MODULE,
>> +		.pm = &isa1200_pm_ops,
>> +	},
>> +	.probe = isa1200_probe,
>> +	.remove = __devexit_p(isa1200_remove),
>> +	.id_table = isa1200_id_table,
>> +};
>> +
>> +static int __init isa1200_init(void)
>> +{
>> +	return i2c_add_driver(&isa1200_driver);
>> +}
>> +module_init(isa1200_init);
>> +
>> +static void __exit isa1200_exit(void)
>> +{
>> +	i2c_del_driver(&isa1200_driver);
>> +}
>> +module_exit(isa1200_exit);
>> +
>> +MODULE_DESCRIPTION("isa1200 based vibrator chip driver");
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_AUTHOR("Kyungmin Park <kyungmin.park@xxxxxxxxxxx>");
>> +MODULE_AUTHOR("Mohan Pallaka <mpallaka@xxxxxxxxxxxxxx>");
>> diff --git a/include/linux/input/isa1200.h b/include/linux/input/isa1200.h
>> new file mode 100644
>> index 0000000..28c18b7
>> --- /dev/null
>> +++ b/include/linux/input/isa1200.h
>> @@ -0,0 +1,45 @@
>> +/*
>> + *  Copyright (C) 2009 Samsung Electronics
>> + *  Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>> + *
>> + *  Copyright (c) 2011, Code Aurora Forum. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#ifndef __LINUX_ISA1200_H
>> +#define __LINUX_ISA1200_H
>> +
>> +enum mode_control {
>> +	POWER_DOWN_MODE = 0,
>> +	PWM_INPUT_MODE,
>> +	PWM_GEN_MODE,
>> +	WAVE_GEN_MODE
>> +};
>> +
>> +union pwm_div_freq {
>> +	unsigned int pwm_div; /* PWM gen mode */
>> +	unsigned int pwm_freq; /* PWM input mode */
>> +};
>> +
>> +struct isa1200_platform_data {
>> +	const char *name;
>> +	unsigned int pwm_ch_id; /* pwm channel id */
>> +	unsigned int max_timeout;
>> +	unsigned int hap_en_gpio;
>> +	bool overdrive_high; /* high/low overdrive */
>> +	bool overdrive_en; /* enable/disable overdrive */
>> +	enum mode_control mode_ctrl; /* input/generation/wave */
>> +	union pwm_div_freq pwm_fd;
>> +	bool smart_en; /* smart mode enable/disable */
>> +	bool is_erm;
>> +	bool ext_clk_en;
>> +	unsigned int chip_en;
>> +	unsigned int duty;
>> +	int (*power_on)(int on);
> bool on?
>
>> +	int (*dev_setup)(bool on);
>> +};
>> +
>> +#endif /* __LINUX_ISA1200_H */
>>
> Thanks.
>
Thanks, Mohan.

-- 
Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

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