1 /*
2 * Copyright (C) 2012 Invensense, Inc.
3 *
4 * This software is licensed under the terms of the GNU General Public
5 * License version 2, as published by the Free Software Foundation, and
6 * may be copied, distributed, and modified under those terms.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * GNU General Public License for more details.
12 */
13 #include <linux/i2c.h>
14 #include <linux/kfifo.h>
15 #include <linux/spinlock.h>
16 #include <linux/iio/iio.h>
17 #include <linux/iio/buffer.h>
18 #include <linux/iio/sysfs.h>
19 #include <linux/iio/kfifo_buf.h>
20 #include <linux/iio/trigger.h>
21 #include <linux/iio/triggered_buffer.h>
22 #include <linux/iio/trigger_consumer.h>
23 #include <linux/platform_data/invensense_mpu6050.h>
24 
25 /**
26  *  struct inv_mpu6050_reg_map - Notable registers.
27  *  @sample_rate_div:	Divider applied to gyro output rate.
28  *  @lpf:		Configures internal low pass filter.
29  *  @user_ctrl:		Enables/resets the FIFO.
30  *  @fifo_en:		Determines which data will appear in FIFO.
31  *  @gyro_config:	gyro config register.
32  *  @accl_config:	accel config register
33  *  @fifo_count_h:	Upper byte of FIFO count.
34  *  @fifo_r_w:		FIFO register.
35  *  @raw_gyro:		Address of first gyro register.
36  *  @raw_accl:		Address of first accel register.
37  *  @temperature:	temperature register
38  *  @int_enable:	Interrupt enable register.
39  *  @pwr_mgmt_1:	Controls chip's power state and clock source.
40  *  @pwr_mgmt_2:	Controls power state of individual sensors.
41  */
42 struct inv_mpu6050_reg_map {
43 	u8 sample_rate_div;
44 	u8 lpf;
45 	u8 user_ctrl;
46 	u8 fifo_en;
47 	u8 gyro_config;
48 	u8 accl_config;
49 	u8 fifo_count_h;
50 	u8 fifo_r_w;
51 	u8 raw_gyro;
52 	u8 raw_accl;
53 	u8 temperature;
54 	u8 int_enable;
55 	u8 pwr_mgmt_1;
56 	u8 pwr_mgmt_2;
57 };
58 
59 /*device enum */
60 enum inv_devices {
61 	INV_MPU6050,
62 	INV_MPU6500,
63 	INV_NUM_PARTS
64 };
65 
66 /**
67  *  struct inv_mpu6050_chip_config - Cached chip configuration data.
68  *  @fsr:		Full scale range.
69  *  @lpf:		Digital low pass filter frequency.
70  *  @accl_fs:		accel full scale range.
71  *  @enable:		master enable state.
72  *  @accl_fifo_enable:	enable accel data output
73  *  @gyro_fifo_enable:	enable gyro data output
74  *  @fifo_rate:		FIFO update rate.
75  */
76 struct inv_mpu6050_chip_config {
77 	unsigned int fsr:2;
78 	unsigned int lpf:3;
79 	unsigned int accl_fs:2;
80 	unsigned int enable:1;
81 	unsigned int accl_fifo_enable:1;
82 	unsigned int gyro_fifo_enable:1;
83 	u16 fifo_rate;
84 };
85 
86 /**
87  *  struct inv_mpu6050_hw - Other important hardware information.
88  *  @num_reg:	Number of registers on device.
89  *  @name:      name of the chip.
90  *  @reg:   register map of the chip.
91  *  @config:    configuration of the chip.
92  */
93 struct inv_mpu6050_hw {
94 	u8 num_reg;
95 	u8 *name;
96 	const struct inv_mpu6050_reg_map *reg;
97 	const struct inv_mpu6050_chip_config *config;
98 };
99 
100 /*
101  *  struct inv_mpu6050_state - Driver state variables.
102  *  @TIMESTAMP_FIFO_SIZE: fifo size for timestamp.
103  *  @trig:              IIO trigger.
104  *  @chip_config:	Cached attribute information.
105  *  @reg:		Map of important registers.
106  *  @hw:		Other hardware-specific information.
107  *  @chip_type:		chip type.
108  *  @time_stamp_lock:	spin lock to time stamp.
109  *  @client:		i2c client handle.
110  *  @plat_data:		platform data.
111  *  @timestamps:        kfifo queue to store time stamp.
112  */
113 struct inv_mpu6050_state {
114 #define TIMESTAMP_FIFO_SIZE 16
115 	struct iio_trigger  *trig;
116 	struct inv_mpu6050_chip_config chip_config;
117 	const struct inv_mpu6050_reg_map *reg;
118 	const struct inv_mpu6050_hw *hw;
119 	enum   inv_devices chip_type;
120 	spinlock_t time_stamp_lock;
121 	struct i2c_client *client;
122 	struct inv_mpu6050_platform_data plat_data;
123 	DECLARE_KFIFO(timestamps, long long, TIMESTAMP_FIFO_SIZE);
124 };
125 
126 /*register and associated bit definition*/
127 #define INV_MPU6050_REG_SAMPLE_RATE_DIV     0x19
128 #define INV_MPU6050_REG_CONFIG              0x1A
129 #define INV_MPU6050_REG_GYRO_CONFIG         0x1B
130 #define INV_MPU6050_REG_ACCEL_CONFIG        0x1C
131 
132 #define INV_MPU6050_REG_FIFO_EN             0x23
133 #define INV_MPU6050_BIT_ACCEL_OUT           0x08
134 #define INV_MPU6050_BITS_GYRO_OUT           0x70
135 
136 #define INV_MPU6050_REG_INT_ENABLE          0x38
137 #define INV_MPU6050_BIT_DATA_RDY_EN         0x01
138 #define INV_MPU6050_BIT_DMP_INT_EN          0x02
139 
140 #define INV_MPU6050_REG_RAW_ACCEL           0x3B
141 #define INV_MPU6050_REG_TEMPERATURE         0x41
142 #define INV_MPU6050_REG_RAW_GYRO            0x43
143 
144 #define INV_MPU6050_REG_USER_CTRL           0x6A
145 #define INV_MPU6050_BIT_FIFO_RST            0x04
146 #define INV_MPU6050_BIT_DMP_RST             0x08
147 #define INV_MPU6050_BIT_I2C_MST_EN          0x20
148 #define INV_MPU6050_BIT_FIFO_EN             0x40
149 #define INV_MPU6050_BIT_DMP_EN              0x80
150 
151 #define INV_MPU6050_REG_PWR_MGMT_1          0x6B
152 #define INV_MPU6050_BIT_H_RESET             0x80
153 #define INV_MPU6050_BIT_SLEEP               0x40
154 #define INV_MPU6050_BIT_CLK_MASK            0x7
155 
156 #define INV_MPU6050_REG_PWR_MGMT_2          0x6C
157 #define INV_MPU6050_BIT_PWR_ACCL_STBY       0x38
158 #define INV_MPU6050_BIT_PWR_GYRO_STBY       0x07
159 
160 #define INV_MPU6050_REG_FIFO_COUNT_H        0x72
161 #define INV_MPU6050_REG_FIFO_R_W            0x74
162 
163 #define INV_MPU6050_BYTES_PER_3AXIS_SENSOR   6
164 #define INV_MPU6050_FIFO_COUNT_BYTE          2
165 #define INV_MPU6050_FIFO_THRESHOLD           500
166 #define INV_MPU6050_POWER_UP_TIME            100
167 #define INV_MPU6050_TEMP_UP_TIME             100
168 #define INV_MPU6050_SENSOR_UP_TIME           30
169 #define INV_MPU6050_REG_UP_TIME              5
170 
171 #define INV_MPU6050_TEMP_OFFSET	             12421
172 #define INV_MPU6050_TEMP_SCALE               2941
173 #define INV_MPU6050_MAX_GYRO_FS_PARAM        3
174 #define INV_MPU6050_MAX_ACCL_FS_PARAM        3
175 #define INV_MPU6050_THREE_AXIS               3
176 #define INV_MPU6050_GYRO_CONFIG_FSR_SHIFT    3
177 #define INV_MPU6050_ACCL_CONFIG_FSR_SHIFT    3
178 
179 /* 6 + 6 round up and plus 8 */
180 #define INV_MPU6050_OUTPUT_DATA_SIZE         24
181 
182 /* init parameters */
183 #define INV_MPU6050_INIT_FIFO_RATE           50
184 #define INV_MPU6050_TIME_STAMP_TOR           5
185 #define INV_MPU6050_MAX_FIFO_RATE            1000
186 #define INV_MPU6050_MIN_FIFO_RATE            4
187 #define INV_MPU6050_ONE_K_HZ                 1000
188 
189 /* scan element definition */
190 enum inv_mpu6050_scan {
191 	INV_MPU6050_SCAN_ACCL_X,
192 	INV_MPU6050_SCAN_ACCL_Y,
193 	INV_MPU6050_SCAN_ACCL_Z,
194 	INV_MPU6050_SCAN_GYRO_X,
195 	INV_MPU6050_SCAN_GYRO_Y,
196 	INV_MPU6050_SCAN_GYRO_Z,
197 	INV_MPU6050_SCAN_TIMESTAMP,
198 };
199 
200 enum inv_mpu6050_filter_e {
201 	INV_MPU6050_FILTER_256HZ_NOLPF2 = 0,
202 	INV_MPU6050_FILTER_188HZ,
203 	INV_MPU6050_FILTER_98HZ,
204 	INV_MPU6050_FILTER_42HZ,
205 	INV_MPU6050_FILTER_20HZ,
206 	INV_MPU6050_FILTER_10HZ,
207 	INV_MPU6050_FILTER_5HZ,
208 	INV_MPU6050_FILTER_2100HZ_NOLPF,
209 	NUM_MPU6050_FILTER
210 };
211 
212 /* IIO attribute address */
213 enum INV_MPU6050_IIO_ATTR_ADDR {
214 	ATTR_GYRO_MATRIX,
215 	ATTR_ACCL_MATRIX,
216 };
217 
218 enum inv_mpu6050_accl_fs_e {
219 	INV_MPU6050_FS_02G = 0,
220 	INV_MPU6050_FS_04G,
221 	INV_MPU6050_FS_08G,
222 	INV_MPU6050_FS_16G,
223 	NUM_ACCL_FSR
224 };
225 
226 enum inv_mpu6050_fsr_e {
227 	INV_MPU6050_FSR_250DPS = 0,
228 	INV_MPU6050_FSR_500DPS,
229 	INV_MPU6050_FSR_1000DPS,
230 	INV_MPU6050_FSR_2000DPS,
231 	NUM_MPU6050_FSR
232 };
233 
234 enum inv_mpu6050_clock_sel_e {
235 	INV_CLK_INTERNAL = 0,
236 	INV_CLK_PLL,
237 	NUM_CLK
238 };
239 
240 irqreturn_t inv_mpu6050_irq_handler(int irq, void *p);
241 irqreturn_t inv_mpu6050_read_fifo(int irq, void *p);
242 int inv_mpu6050_probe_trigger(struct iio_dev *indio_dev);
243 void inv_mpu6050_remove_trigger(struct inv_mpu6050_state *st);
244 int inv_reset_fifo(struct iio_dev *indio_dev);
245 int inv_mpu6050_switch_engine(struct inv_mpu6050_state *st, bool en, u32 mask);
246 int inv_mpu6050_write_reg(struct inv_mpu6050_state *st, int reg, u8 val);
247 int inv_mpu6050_set_power_itg(struct inv_mpu6050_state *st, bool power_on);
248