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Release 4.11 drivers/input/misc/mma8450.c

/*
 *  Driver for Freescale's 3-Axis Accelerometer MMA8450
 *
 *  Copyright (C) 2011 Freescale Semiconductor, Inc. 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 as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/input-polldev.h>
#include <linux/of_device.h>


#define MMA8450_DRV_NAME	"mma8450"


#define MODE_CHANGE_DELAY_MS	100

#define POLL_INTERVAL		100

#define POLL_INTERVAL_MAX	500

/* register definitions */

#define MMA8450_STATUS		0x00

#define MMA8450_STATUS_ZXYDR	0x08


#define MMA8450_OUT_X8		0x01

#define MMA8450_OUT_Y8		0x02

#define MMA8450_OUT_Z8		0x03


#define MMA8450_OUT_X_LSB	0x05

#define MMA8450_OUT_X_MSB	0x06

#define MMA8450_OUT_Y_LSB	0x07

#define MMA8450_OUT_Y_MSB	0x08

#define MMA8450_OUT_Z_LSB	0x09

#define MMA8450_OUT_Z_MSB	0x0a


#define MMA8450_XYZ_DATA_CFG	0x16


#define MMA8450_CTRL_REG1	0x38

#define MMA8450_CTRL_REG2	0x39

/* mma8450 status */

struct mma8450 {
	
struct i2c_client	*client;
	
struct input_polled_dev	*idev;
};


static int mma8450_read(struct mma8450 *m, unsigned off) { struct i2c_client *c = m->client; int ret; ret = i2c_smbus_read_byte_data(c, off); if (ret < 0) dev_err(&c->dev, "failed to read register 0x%02x, error %d\n", off, ret); return ret; }

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Eric Miao58100.00%1100.00%
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static int mma8450_write(struct mma8450 *m, unsigned off, u8 v) { struct i2c_client *c = m->client; int error; error = i2c_smbus_write_byte_data(c, off, v); if (error < 0) { dev_err(&c->dev, "failed to write to register 0x%02x, error %d\n", off, error); return error; } return 0; }

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Eric Miao68100.00%1100.00%
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static int mma8450_read_block(struct mma8450 *m, unsigned off, u8 *buf, size_t size) { struct i2c_client *c = m->client; int err; err = i2c_smbus_read_i2c_block_data(c, off, size, buf); if (err < 0) { dev_err(&c->dev, "failed to read block data at 0x%02x, error %d\n", MMA8450_OUT_X_LSB, err); return err; } return 0; }

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Eric Miao6486.49%150.00%
Dmitry Torokhov1013.51%150.00%
Total74100.00%2100.00%


static void mma8450_poll(struct input_polled_dev *dev) { struct mma8450 *m = dev->private; int x, y, z; int ret; u8 buf[6]; ret = mma8450_read(m, MMA8450_STATUS); if (ret < 0) return; if (!(ret & MMA8450_STATUS_ZXYDR)) return; ret = mma8450_read_block(m, MMA8450_OUT_X_LSB, buf, sizeof(buf)); if (ret < 0) return; x = ((int)(s8)buf[1] << 4) | (buf[0] & 0xf); y = ((int)(s8)buf[3] << 4) | (buf[2] & 0xf); z = ((int)(s8)buf[5] << 4) | (buf[4] & 0xf); input_report_abs(dev->input, ABS_X, x); input_report_abs(dev->input, ABS_Y, y); input_report_abs(dev->input, ABS_Z, z); input_sync(dev->input); }

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Sebastien Royen157.39%133.33%
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/* Initialize the MMA8450 chip */
static void mma8450_open(struct input_polled_dev *dev) { struct mma8450 *m = dev->private; int err; /* enable all events from X/Y/Z, no FIFO */ err = mma8450_write(m, MMA8450_XYZ_DATA_CFG, 0x07); if (err) return; /* * Sleep mode poll rate - 50Hz * System output data rate - 400Hz * Full scale selection - Active, +/- 2G */ err = mma8450_write(m, MMA8450_CTRL_REG1, 0x01); if (err < 0) return; msleep(MODE_CHANGE_DELAY_MS); }

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static void mma8450_close(struct input_polled_dev *dev) { struct mma8450 *m = dev->private; mma8450_write(m, MMA8450_CTRL_REG1, 0x00); mma8450_write(m, MMA8450_CTRL_REG2, 0x01); }

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Eric Miao38100.00%1100.00%
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/* * I2C init/probing/exit functions */
static int mma8450_probe(struct i2c_client *c, const struct i2c_device_id *id) { struct input_polled_dev *idev; struct mma8450 *m; int err; m = devm_kzalloc(&c->dev, sizeof(*m), GFP_KERNEL); if (!m) return -ENOMEM; idev = devm_input_allocate_polled_device(&c->dev); if (!idev) return -ENOMEM; m->client = c; m->idev = idev; idev->private = m; idev->input->name = MMA8450_DRV_NAME; idev->input->id.bustype = BUS_I2C; idev->poll = mma8450_poll; idev->poll_interval = POLL_INTERVAL; idev->poll_interval_max = POLL_INTERVAL_MAX; idev->open = mma8450_open; idev->close = mma8450_close; __set_bit(EV_ABS, idev->input->evbit); input_set_abs_params(idev->input, ABS_X, -2048, 2047, 32, 32); input_set_abs_params(idev->input, ABS_Y, -2048, 2047, 32, 32); input_set_abs_params(idev->input, ABS_Z, -2048, 2047, 32, 32); err = input_register_polled_device(idev); if (err) { dev_err(&c->dev, "failed to register polled input device\n"); return err; } return 0; }

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static const struct i2c_device_id mma8450_id[] = { { MMA8450_DRV_NAME, 0 }, { }, }; MODULE_DEVICE_TABLE(i2c, mma8450_id); static const struct of_device_id mma8450_dt_ids[] = { { .compatible = "fsl,mma8450", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, mma8450_dt_ids); static struct i2c_driver mma8450_driver = { .driver = { .name = MMA8450_DRV_NAME, .of_match_table = mma8450_dt_ids, }, .probe = mma8450_probe, .id_table = mma8450_id, }; module_i2c_driver(mma8450_driver); MODULE_AUTHOR("Freescale Semiconductor, Inc."); MODULE_DESCRIPTION("MMA8450 3-Axis Accelerometer Driver"); MODULE_LICENSE("GPL");

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Shawn Guo323.34%114.29%
Sebastien Royen151.57%114.29%
Axel Lin20.21%228.57%
Total957100.00%7100.00%
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