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/init.h>
15#include <linux/kernel.h>
16#include <linux/errno.h>
17#include <linux/platform_device.h>
18#include <linux/input.h>
19#include <linux/slab.h>
20#include <linux/mfd/pm8xxx/core.h>
21
22#define VIB_DRV			0x4A
23
24#define VIB_DRV_SEL_MASK	0xf8
25#define VIB_DRV_SEL_SHIFT	0x03
26#define VIB_DRV_EN_MANUAL_MASK	0xfc
27
28#define VIB_MAX_LEVEL_mV	(3100)
29#define VIB_MIN_LEVEL_mV	(1200)
30#define VIB_MAX_LEVELS		(VIB_MAX_LEVEL_mV - VIB_MIN_LEVEL_mV)
31
32#define MAX_FF_SPEED		0xff
33
34/**
35 * struct pm8xxx_vib - structure to hold vibrator data
36 * @vib_input_dev: input device supporting force feedback
37 * @work: work structure to set the vibration parameters
38 * @dev: device supporting force feedback
39 * @speed: speed of vibration set from userland
40 * @active: state of vibrator
41 * @level: level of vibration to set in the chip
42 * @reg_vib_drv: VIB_DRV register value
43 */
44struct pm8xxx_vib {
45	struct input_dev *vib_input_dev;
46	struct work_struct work;
47	struct device *dev;
48	int speed;
49	int level;
50	bool active;
51	u8  reg_vib_drv;
52};
53
54/**
55 * pm8xxx_vib_read_u8 - helper to read a byte from pmic chip
56 * @vib: pointer to vibrator structure
57 * @data: placeholder for data to be read
58 * @reg: register address
59 */
60static int pm8xxx_vib_read_u8(struct pm8xxx_vib *vib,
61				 u8 *data, u16 reg)
62{
63	int rc;
64
65	rc = pm8xxx_readb(vib->dev->parent, reg, data);
66	if (rc < 0)
67		dev_warn(vib->dev, "Error reading pm8xxx reg 0x%x(0x%x)\n",
68				reg, rc);
69	return rc;
70}
71
72/**
73 * pm8xxx_vib_write_u8 - helper to write a byte to pmic chip
74 * @vib: pointer to vibrator structure
75 * @data: data to write
76 * @reg: register address
77 */
78static int pm8xxx_vib_write_u8(struct pm8xxx_vib *vib,
79				 u8 data, u16 reg)
80{
81	int rc;
82
83	rc = pm8xxx_writeb(vib->dev->parent, reg, data);
84	if (rc < 0)
85		dev_warn(vib->dev, "Error writing pm8xxx reg 0x%x(0x%x)\n",
86				reg, rc);
87	return rc;
88}
89
90/**
91 * pm8xxx_vib_set - handler to start/stop vibration
92 * @vib: pointer to vibrator structure
93 * @on: state to set
94 */
95static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
96{
97	int rc;
98	u8 val = vib->reg_vib_drv;
99
100	if (on)
101		val |= ((vib->level << VIB_DRV_SEL_SHIFT) & VIB_DRV_SEL_MASK);
102	else
103		val &= ~VIB_DRV_SEL_MASK;
104
105	rc = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
106	if (rc < 0)
107		return rc;
108
109	vib->reg_vib_drv = val;
110	return 0;
111}
112
113/**
114 * pm8xxx_work_handler - worker to set vibration level
115 * @work: pointer to work_struct
116 */
117static void pm8xxx_work_handler(struct work_struct *work)
118{
119	struct pm8xxx_vib *vib = container_of(work, struct pm8xxx_vib, work);
120	int rc;
121	u8 val;
122
123	rc = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
124	if (rc < 0)
125		return;
126
127	/*
128	 * pmic vibrator supports voltage ranges from 1.2 to 3.1V, so
129	 * scale the level to fit into these ranges.
130	 */
131	if (vib->speed) {
132		vib->active = true;
133		vib->level = ((VIB_MAX_LEVELS * vib->speed) / MAX_FF_SPEED) +
134						VIB_MIN_LEVEL_mV;
135		vib->level /= 100;
136	} else {
137		vib->active = false;
138		vib->level = VIB_MIN_LEVEL_mV / 100;
139	}
140
141	pm8xxx_vib_set(vib, vib->active);
142}
143
144/**
145 * pm8xxx_vib_close - callback of input close callback
146 * @dev: input device pointer
147 *
148 * Turns off the vibrator.
149 */
150static void pm8xxx_vib_close(struct input_dev *dev)
151{
152	struct pm8xxx_vib *vib = input_get_drvdata(dev);
153
154	cancel_work_sync(&vib->work);
155	if (vib->active)
156		pm8xxx_vib_set(vib, false);
157}
158
159/**
160 * pm8xxx_vib_play_effect - function to handle vib effects.
161 * @dev: input device pointer
162 * @data: data of effect
163 * @effect: effect to play
164 *
165 * Currently this driver supports only rumble effects.
166 */
167static int pm8xxx_vib_play_effect(struct input_dev *dev, void *data,
168				  struct ff_effect *effect)
169{
170	struct pm8xxx_vib *vib = input_get_drvdata(dev);
171
172	vib->speed = effect->u.rumble.strong_magnitude >> 8;
173	if (!vib->speed)
174		vib->speed = effect->u.rumble.weak_magnitude >> 9;
175
176	schedule_work(&vib->work);
177
178	return 0;
179}
180
181static int __devinit pm8xxx_vib_probe(struct platform_device *pdev)
182
183{
184	struct pm8xxx_vib *vib;
185	struct input_dev *input_dev;
186	int error;
187	u8 val;
188
189	vib = kzalloc(sizeof(*vib), GFP_KERNEL);
190	input_dev = input_allocate_device();
191	if (!vib || !input_dev) {
192		dev_err(&pdev->dev, "couldn't allocate memory\n");
193		error = -ENOMEM;
194		goto err_free_mem;
195	}
196
197	INIT_WORK(&vib->work, pm8xxx_work_handler);
198	vib->dev = &pdev->dev;
199	vib->vib_input_dev = input_dev;
200
201	/* operate in manual mode */
202	error = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
203	if (error < 0)
204		goto err_free_mem;
205	val &= ~VIB_DRV_EN_MANUAL_MASK;
206	error = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
207	if (error < 0)
208		goto err_free_mem;
209
210	vib->reg_vib_drv = val;
211
212	input_dev->name = "pm8xxx_vib_ffmemless";
213	input_dev->id.version = 1;
214	input_dev->dev.parent = &pdev->dev;
215	input_dev->close = pm8xxx_vib_close;
216	input_set_drvdata(input_dev, vib);
217	input_set_capability(vib->vib_input_dev, EV_FF, FF_RUMBLE);
218
219	error = input_ff_create_memless(input_dev, NULL,
220					pm8xxx_vib_play_effect);
221	if (error) {
222		dev_err(&pdev->dev,
223			"couldn't register vibrator as FF device\n");
224		goto err_free_mem;
225	}
226
227	error = input_register_device(input_dev);
228	if (error) {
229		dev_err(&pdev->dev, "couldn't register input device\n");
230		goto err_destroy_memless;
231	}
232
233	platform_set_drvdata(pdev, vib);
234	return 0;
235
236err_destroy_memless:
237	input_ff_destroy(input_dev);
238err_free_mem:
239	input_free_device(input_dev);
240	kfree(vib);
241
242	return error;
243}
244
245static int __devexit pm8xxx_vib_remove(struct platform_device *pdev)
246{
247	struct pm8xxx_vib *vib = platform_get_drvdata(pdev);
248
249	input_unregister_device(vib->vib_input_dev);
250	kfree(vib);
251
252	platform_set_drvdata(pdev, NULL);
253
254	return 0;
255}
256
257#ifdef CONFIG_PM_SLEEP
258static int pm8xxx_vib_suspend(struct device *dev)
259{
260	struct pm8xxx_vib *vib = dev_get_drvdata(dev);
261
262	/* Turn off the vibrator */
263	pm8xxx_vib_set(vib, false);
264
265	return 0;
266}
267#endif
268
269static SIMPLE_DEV_PM_OPS(pm8xxx_vib_pm_ops, pm8xxx_vib_suspend, NULL);
270
271static struct platform_driver pm8xxx_vib_driver = {
272	.probe		= pm8xxx_vib_probe,
273	.remove		= __devexit_p(pm8xxx_vib_remove),
274	.driver		= {
275		.name	= "pm8xxx-vib",
276		.owner	= THIS_MODULE,
277		.pm	= &pm8xxx_vib_pm_ops,
278	},
279};
280module_platform_driver(pm8xxx_vib_driver);
281
282MODULE_ALIAS("platform:pm8xxx_vib");
283MODULE_DESCRIPTION("PMIC8xxx vibrator driver based on ff-memless framework");
284MODULE_LICENSE("GPL v2");
285MODULE_AUTHOR("Amy Maloche <amaloche@codeaurora.org>");
286