/*
   * twl6040-vibra.c - TWL6040 Vibrator driver
   *
   * Author:      Jorge Eduardo Candelaria <jorge.candelaria@ti.com>
   * Author:      Misael Lopez Cruz <misael.lopez@ti.com>
   *
   * Copyright:   (C) 2011 Texas Instruments, Inc.
   *
   * Based on twl4030-vibra.c by Henrik Saari <henrik.saari@nokia.com>
   *				Felipe Balbi <felipe.balbi@nokia.com>
   *				Jari Vanhala <ext-javi.vanhala@nokia.com>
   *
   * 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.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
   * 02110-1301 USA
   *
   */
  #include <linux/module.h>
  #include <linux/platform_device.h>
  #include <linux/of.h>
  #include <linux/workqueue.h>
  #include <linux/input.h>
  #include <linux/mfd/twl6040.h>
  #include <linux/slab.h>
  #include <linux/delay.h>
  #include <linux/regulator/consumer.h>
  
  #define EFFECT_DIR_180_DEG	0x8000
  
  /* Recommended modulation index 85% */
  #define TWL6040_VIBRA_MOD	85
  
  #define TWL6040_NUM_SUPPLIES 2
  
  struct vibra_info {
  	struct device *dev;
  	struct input_dev *input_dev;
  	struct workqueue_struct *workqueue;
  	struct work_struct play_work;
  	struct mutex mutex;
  	int irq;
  
  	bool enabled;
  	int weak_speed;
  	int strong_speed;
  	int direction;
  
  	unsigned int vibldrv_res;
  	unsigned int vibrdrv_res;
  	unsigned int viblmotor_res;
  	unsigned int vibrmotor_res;
  
  	struct regulator_bulk_data supplies[TWL6040_NUM_SUPPLIES];
  
  	struct twl6040 *twl6040;
  };
  
  static irqreturn_t twl6040_vib_irq_handler(int irq, void *data)
  {
  	struct vibra_info *info = data;
  	struct twl6040 *twl6040 = info->twl6040;
  	u8 status;
  
  	status = twl6040_reg_read(twl6040, TWL6040_REG_STATUS);
  	if (status & TWL6040_VIBLOCDET) {
  		dev_warn(info->dev, "Left Vibrator overcurrent detected
  ");
  		twl6040_clear_bits(twl6040, TWL6040_REG_VIBCTLL,
  				   TWL6040_VIBENA);
  	}
  	if (status & TWL6040_VIBROCDET) {
  		dev_warn(info->dev, "Right Vibrator overcurrent detected
  ");
  		twl6040_clear_bits(twl6040, TWL6040_REG_VIBCTLR,
  				   TWL6040_VIBENA);
  	}
  
  	return IRQ_HANDLED;
  }
  
  static void twl6040_vibra_enable(struct vibra_info *info)
  {
  	struct twl6040 *twl6040 = info->twl6040;
  	int ret;
  
  	ret = regulator_bulk_enable(ARRAY_SIZE(info->supplies), info->supplies);
  	if (ret) {
  		dev_err(info->dev, "failed to enable regulators %d
  ", ret);
  		return;
  	}
  
  	twl6040_power(info->twl6040, 1);
  	if (twl6040_get_revid(twl6040) <= TWL6040_REV_ES1_1) {
  		/*
  		 * ERRATA: Disable overcurrent protection for at least
  		 * 3ms when enabling vibrator drivers to avoid false
  		 * overcurrent detection
  		 */
  		twl6040_reg_write(twl6040, TWL6040_REG_VIBCTLL,
  				  TWL6040_VIBENA | TWL6040_VIBCTRL);
  		twl6040_reg_write(twl6040, TWL6040_REG_VIBCTLR,
  				  TWL6040_VIBENA | TWL6040_VIBCTRL);
  		usleep_range(3000, 3500);
  	}
  
  	twl6040_reg_write(twl6040, TWL6040_REG_VIBCTLL,
  			  TWL6040_VIBENA);
  	twl6040_reg_write(twl6040, TWL6040_REG_VIBCTLR,
  			  TWL6040_VIBENA);
  
  	info->enabled = true;
  }
  
  static void twl6040_vibra_disable(struct vibra_info *info)
  {
  	struct twl6040 *twl6040 = info->twl6040;
  
  	twl6040_reg_write(twl6040, TWL6040_REG_VIBCTLL, 0x00);
  	twl6040_reg_write(twl6040, TWL6040_REG_VIBCTLR, 0x00);
  	twl6040_power(info->twl6040, 0);
  
  	regulator_bulk_disable(ARRAY_SIZE(info->supplies), info->supplies);
  
  	info->enabled = false;
  }
  
  static u8 twl6040_vibra_code(int vddvib, int vibdrv_res, int motor_res,
  			     int speed, int direction)
  {
  	int vpk, max_code;
  	u8 vibdat;
  
  	/* output swing */
  	vpk = (vddvib * motor_res * TWL6040_VIBRA_MOD) /
  		(100 * (vibdrv_res + motor_res));
  
  	/* 50mV per VIBDAT code step */
  	max_code = vpk / 50;
  	if (max_code > TWL6040_VIBDAT_MAX)
  		max_code = TWL6040_VIBDAT_MAX;
  
  	/* scale speed to max allowed code */
  	vibdat = (u8)((speed * max_code) / USHRT_MAX);
  
  	/* 2's complement for direction > 180 degrees */
  	vibdat *= direction;
  
  	return vibdat;
  }
  
  static void twl6040_vibra_set_effect(struct vibra_info *info)
  {
  	struct twl6040 *twl6040 = info->twl6040;
  	u8 vibdatl, vibdatr;
  	int volt;
  
  	/* weak motor */
  	volt = regulator_get_voltage(info->supplies[0].consumer) / 1000;
  	vibdatl = twl6040_vibra_code(volt, info->vibldrv_res,
  				     info->viblmotor_res,
  				     info->weak_speed, info->direction);
  
  	/* strong motor */
  	volt = regulator_get_voltage(info->supplies[1].consumer) / 1000;
  	vibdatr = twl6040_vibra_code(volt, info->vibrdrv_res,
  				     info->vibrmotor_res,
  				     info->strong_speed, info->direction);
  
  	twl6040_reg_write(twl6040, TWL6040_REG_VIBDATL, vibdatl);
  	twl6040_reg_write(twl6040, TWL6040_REG_VIBDATR, vibdatr);
  }
  
  static void vibra_play_work(struct work_struct *work)
  {
  	struct vibra_info *info = container_of(work,
  				struct vibra_info, play_work);
  
  	mutex_lock(&info->mutex);
  
  	if (info->weak_speed || info->strong_speed) {
  		if (!info->enabled)
  			twl6040_vibra_enable(info);
  
  		twl6040_vibra_set_effect(info);
  	} else if (info->enabled)
  		twl6040_vibra_disable(info);
  
  	mutex_unlock(&info->mutex);
  }
  
  static int vibra_play(struct input_dev *input, void *data,
  		      struct ff_effect *effect)
  {
  	struct vibra_info *info = input_get_drvdata(input);
  	int ret;
  
  	/* Do not allow effect, while the routing is set to use audio */
  	ret = twl6040_get_vibralr_status(info->twl6040);
  	if (ret & TWL6040_VIBSEL) {
  		dev_info(&input->dev, "Vibra is configured for audio
  ");
  		return -EBUSY;
  	}
  
  	info->weak_speed = effect->u.rumble.weak_magnitude;
  	info->strong_speed = effect->u.rumble.strong_magnitude;
  	info->direction = effect->direction < EFFECT_DIR_180_DEG ? 1 : -1;
  
  	ret = queue_work(info->workqueue, &info->play_work);
  	if (!ret) {
  		dev_info(&input->dev, "work is already on queue
  ");
  		return ret;
  	}
  
  	return 0;
  }
  
  static void twl6040_vibra_close(struct input_dev *input)
  {
  	struct vibra_info *info = input_get_drvdata(input);
  
  	cancel_work_sync(&info->play_work);
  
  	mutex_lock(&info->mutex);
  
  	if (info->enabled)
  		twl6040_vibra_disable(info);
  
  	mutex_unlock(&info->mutex);
  }
  
  static int __maybe_unused twl6040_vibra_suspend(struct device *dev)
  {
  	struct platform_device *pdev = to_platform_device(dev);
  	struct vibra_info *info = platform_get_drvdata(pdev);
  
  	mutex_lock(&info->mutex);
  
  	if (info->enabled)
  		twl6040_vibra_disable(info);
  
  	mutex_unlock(&info->mutex);
  
  	return 0;
  }
  
  static SIMPLE_DEV_PM_OPS(twl6040_vibra_pm_ops, twl6040_vibra_suspend, NULL);
  
  static int twl6040_vibra_probe(struct platform_device *pdev)
  {
  	struct device *twl6040_core_dev = pdev->dev.parent;
  	struct device_node *twl6040_core_node;
  	struct vibra_info *info;
  	int vddvibl_uV = 0;
  	int vddvibr_uV = 0;
  	int error;
  
  	twl6040_core_node = of_find_node_by_name(twl6040_core_dev->of_node,
  						 "vibra");
  	if (!twl6040_core_node) {
  		dev_err(&pdev->dev, "parent of node is missing?
  ");
  		return -EINVAL;
  	}
  
  	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
  	if (!info) {
  		of_node_put(twl6040_core_node);
  		dev_err(&pdev->dev, "couldn't allocate memory
  ");
  		return -ENOMEM;
  	}
  
  	info->dev = &pdev->dev;
  
  	info->twl6040 = dev_get_drvdata(pdev->dev.parent);
  
  	of_property_read_u32(twl6040_core_node, "ti,vibldrv-res",
  			     &info->vibldrv_res);
  	of_property_read_u32(twl6040_core_node, "ti,vibrdrv-res",
  			     &info->vibrdrv_res);
  	of_property_read_u32(twl6040_core_node, "ti,viblmotor-res",
  			     &info->viblmotor_res);
  	of_property_read_u32(twl6040_core_node, "ti,vibrmotor-res",
  			     &info->vibrmotor_res);
  	of_property_read_u32(twl6040_core_node, "ti,vddvibl-uV", &vddvibl_uV);
  	of_property_read_u32(twl6040_core_node, "ti,vddvibr-uV", &vddvibr_uV);
  
  	of_node_put(twl6040_core_node);
  
  	if ((!info->vibldrv_res && !info->viblmotor_res) ||
  	    (!info->vibrdrv_res && !info->vibrmotor_res)) {
  		dev_err(info->dev, "invalid vibra driver/motor resistance
  ");
  		return -EINVAL;
  	}
  
  	info->irq = platform_get_irq(pdev, 0);
  	if (info->irq < 0) {
  		dev_err(info->dev, "invalid irq
  ");
  		return -EINVAL;
  	}
  
  	mutex_init(&info->mutex);
  
  	error = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
  					  twl6040_vib_irq_handler,
  					  IRQF_ONESHOT,
  					  "twl6040_irq_vib", info);
  	if (error) {
  		dev_err(info->dev, "VIB IRQ request failed: %d
  ", error);
  		return error;
  	}
  
  	info->supplies[0].supply = "vddvibl";
  	info->supplies[1].supply = "vddvibr";
  	/*
  	 * When booted with Device tree the regulators are attached to the
  	 * parent device (twl6040 MFD core)
  	 */
  	error = devm_regulator_bulk_get(twl6040_core_dev,
  					ARRAY_SIZE(info->supplies),
  					info->supplies);
  	if (error) {
  		dev_err(info->dev, "couldn't get regulators %d
  ", error);
  		return error;
  	}
  
  	if (vddvibl_uV) {
  		error = regulator_set_voltage(info->supplies[0].consumer,
  					      vddvibl_uV, vddvibl_uV);
  		if (error) {
  			dev_err(info->dev, "failed to set VDDVIBL volt %d
  ",
  				error);
  			return error;
  		}
  	}
  
  	if (vddvibr_uV) {
  		error = regulator_set_voltage(info->supplies[1].consumer,
  					      vddvibr_uV, vddvibr_uV);
  		if (error) {
  			dev_err(info->dev, "failed to set VDDVIBR volt %d
  ",
  				error);
  			return error;
  		}
  	}
  
  	INIT_WORK(&info->play_work, vibra_play_work);
  
  	info->input_dev = devm_input_allocate_device(&pdev->dev);
  	if (!info->input_dev) {
  		dev_err(info->dev, "couldn't allocate input device
  ");
  		return -ENOMEM;
  	}
  
  	input_set_drvdata(info->input_dev, info);
  
  	info->input_dev->name = "twl6040:vibrator";
  	info->input_dev->id.version = 1;
  	info->input_dev->dev.parent = pdev->dev.parent;
  	info->input_dev->close = twl6040_vibra_close;
  	__set_bit(FF_RUMBLE, info->input_dev->ffbit);
  
  	error = input_ff_create_memless(info->input_dev, NULL, vibra_play);
  	if (error) {
  		dev_err(info->dev, "couldn't register vibrator to FF
  ");
  		return error;
  	}
  
  	error = input_register_device(info->input_dev);
  	if (error) {
  		dev_err(info->dev, "couldn't register input device
  ");
  		return error;
  	}
  
  	platform_set_drvdata(pdev, info);
  
  	return 0;
  }
  
  static struct platform_driver twl6040_vibra_driver = {
  	.probe		= twl6040_vibra_probe,
  	.driver		= {
  		.name	= "twl6040-vibra",
  		.pm	= &twl6040_vibra_pm_ops,
  	},
  };
  module_platform_driver(twl6040_vibra_driver);
  
  MODULE_ALIAS("platform:twl6040-vibra");
  MODULE_DESCRIPTION("TWL6040 Vibra driver");
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Jorge Eduardo Candelaria <jorge.candelaria@ti.com>");
  MODULE_AUTHOR("Misael Lopez Cruz <misael.lopez@ti.com>");