1 /* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/platform_device.h>
17 #include <linux/input.h>
18 #include <linux/slab.h>
19 #include <linux/regmap.h>
20 
21 #define VIB_DRV			0x4A
22 
23 #define VIB_DRV_SEL_MASK	0xf8
24 #define VIB_DRV_SEL_SHIFT	0x03
25 #define VIB_DRV_EN_MANUAL_MASK	0xfc
26 
27 #define VIB_MAX_LEVEL_mV	(3100)
28 #define VIB_MIN_LEVEL_mV	(1200)
29 #define VIB_MAX_LEVELS		(VIB_MAX_LEVEL_mV - VIB_MIN_LEVEL_mV)
30 
31 #define MAX_FF_SPEED		0xff
32 
33 /**
34  * struct pm8xxx_vib - structure to hold vibrator data
35  * @vib_input_dev: input device supporting force feedback
36  * @work: work structure to set the vibration parameters
37  * @regmap: regmap for register read/write
38  * @speed: speed of vibration set from userland
39  * @active: state of vibrator
40  * @level: level of vibration to set in the chip
41  * @reg_vib_drv: VIB_DRV register value
42  */
43 struct pm8xxx_vib {
44 	struct input_dev *vib_input_dev;
45 	struct work_struct work;
46 	struct regmap *regmap;
47 	int speed;
48 	int level;
49 	bool active;
50 	u8  reg_vib_drv;
51 };
52 
53 /**
54  * pm8xxx_vib_set - handler to start/stop vibration
55  * @vib: pointer to vibrator structure
56  * @on: state to set
57  */
58 static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
59 {
60 	int rc;
61 	unsigned int val = vib->reg_vib_drv;
62 
63 	if (on)
64 		val |= ((vib->level << VIB_DRV_SEL_SHIFT) & VIB_DRV_SEL_MASK);
65 	else
66 		val &= ~VIB_DRV_SEL_MASK;
67 
68 	rc = regmap_write(vib->regmap, VIB_DRV, val);
69 	if (rc < 0)
70 		return rc;
71 
72 	vib->reg_vib_drv = val;
73 	return 0;
74 }
75 
76 /**
77  * pm8xxx_work_handler - worker to set vibration level
78  * @work: pointer to work_struct
79  */
80 static void pm8xxx_work_handler(struct work_struct *work)
81 {
82 	struct pm8xxx_vib *vib = container_of(work, struct pm8xxx_vib, work);
83 	int rc;
84 	unsigned int val;
85 
86 	rc = regmap_read(vib->regmap, VIB_DRV, &val);
87 	if (rc < 0)
88 		return;
89 
90 	/*
91 	 * pmic vibrator supports voltage ranges from 1.2 to 3.1V, so
92 	 * scale the level to fit into these ranges.
93 	 */
94 	if (vib->speed) {
95 		vib->active = true;
96 		vib->level = ((VIB_MAX_LEVELS * vib->speed) / MAX_FF_SPEED) +
97 						VIB_MIN_LEVEL_mV;
98 		vib->level /= 100;
99 	} else {
100 		vib->active = false;
101 		vib->level = VIB_MIN_LEVEL_mV / 100;
102 	}
103 
104 	pm8xxx_vib_set(vib, vib->active);
105 }
106 
107 /**
108  * pm8xxx_vib_close - callback of input close callback
109  * @dev: input device pointer
110  *
111  * Turns off the vibrator.
112  */
113 static void pm8xxx_vib_close(struct input_dev *dev)
114 {
115 	struct pm8xxx_vib *vib = input_get_drvdata(dev);
116 
117 	cancel_work_sync(&vib->work);
118 	if (vib->active)
119 		pm8xxx_vib_set(vib, false);
120 }
121 
122 /**
123  * pm8xxx_vib_play_effect - function to handle vib effects.
124  * @dev: input device pointer
125  * @data: data of effect
126  * @effect: effect to play
127  *
128  * Currently this driver supports only rumble effects.
129  */
130 static int pm8xxx_vib_play_effect(struct input_dev *dev, void *data,
131 				  struct ff_effect *effect)
132 {
133 	struct pm8xxx_vib *vib = input_get_drvdata(dev);
134 
135 	vib->speed = effect->u.rumble.strong_magnitude >> 8;
136 	if (!vib->speed)
137 		vib->speed = effect->u.rumble.weak_magnitude >> 9;
138 
139 	schedule_work(&vib->work);
140 
141 	return 0;
142 }
143 
144 static int pm8xxx_vib_probe(struct platform_device *pdev)
145 
146 {
147 	struct pm8xxx_vib *vib;
148 	struct input_dev *input_dev;
149 	int error;
150 	unsigned int val;
151 
152 	vib = devm_kzalloc(&pdev->dev, sizeof(*vib), GFP_KERNEL);
153 	if (!vib)
154 		return -ENOMEM;
155 
156 	vib->regmap = dev_get_regmap(pdev->dev.parent, NULL);
157 	if (!vib->regmap)
158 		return -ENODEV;
159 
160 	input_dev = devm_input_allocate_device(&pdev->dev);
161 	if (!input_dev)
162 		return -ENOMEM;
163 
164 	INIT_WORK(&vib->work, pm8xxx_work_handler);
165 	vib->vib_input_dev = input_dev;
166 
167 	/* operate in manual mode */
168 	error = regmap_read(vib->regmap, VIB_DRV, &val);
169 	if (error < 0)
170 		return error;
171 
172 	val &= ~VIB_DRV_EN_MANUAL_MASK;
173 	error = regmap_write(vib->regmap, VIB_DRV, val);
174 	if (error < 0)
175 		return error;
176 
177 	vib->reg_vib_drv = val;
178 
179 	input_dev->name = "pm8xxx_vib_ffmemless";
180 	input_dev->id.version = 1;
181 	input_dev->close = pm8xxx_vib_close;
182 	input_set_drvdata(input_dev, vib);
183 	input_set_capability(vib->vib_input_dev, EV_FF, FF_RUMBLE);
184 
185 	error = input_ff_create_memless(input_dev, NULL,
186 					pm8xxx_vib_play_effect);
187 	if (error) {
188 		dev_err(&pdev->dev,
189 			"couldn't register vibrator as FF device\n");
190 		return error;
191 	}
192 
193 	error = input_register_device(input_dev);
194 	if (error) {
195 		dev_err(&pdev->dev, "couldn't register input device\n");
196 		return error;
197 	}
198 
199 	platform_set_drvdata(pdev, vib);
200 	return 0;
201 }
202 
203 #ifdef CONFIG_PM_SLEEP
204 static int pm8xxx_vib_suspend(struct device *dev)
205 {
206 	struct pm8xxx_vib *vib = dev_get_drvdata(dev);
207 
208 	/* Turn off the vibrator */
209 	pm8xxx_vib_set(vib, false);
210 
211 	return 0;
212 }
213 #endif
214 
215 static SIMPLE_DEV_PM_OPS(pm8xxx_vib_pm_ops, pm8xxx_vib_suspend, NULL);
216 
217 static struct platform_driver pm8xxx_vib_driver = {
218 	.probe		= pm8xxx_vib_probe,
219 	.driver		= {
220 		.name	= "pm8xxx-vib",
221 		.owner	= THIS_MODULE,
222 		.pm	= &pm8xxx_vib_pm_ops,
223 	},
224 };
225 module_platform_driver(pm8xxx_vib_driver);
226 
227 MODULE_ALIAS("platform:pm8xxx_vib");
228 MODULE_DESCRIPTION("PMIC8xxx vibrator driver based on ff-memless framework");
229 MODULE_LICENSE("GPL v2");
230 MODULE_AUTHOR("Amy Maloche <amaloche@codeaurora.org>");
231