/* * Copyright (C) 2011 Kionix, Inc. * Written by Chris Hudson <chudson@kionix.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., 59 Temple Place, Suite 330, Boston, MA * 02111-1307, USA */ #include <linux/delay.h> #include <linux/i2c.h> #include <linux/input.h> #include <linux/interrupt.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/input/kxtj9.h> #include <linux/input-polldev.h> #define NAME "kxtj9" #define G_MAX 8000 /* OUTPUT REGISTERS */ #define XOUT_L 0x06 #define WHO_AM_I 0x0F /* CONTROL REGISTERS */ #define INT_REL 0x1A #define CTRL_REG1 0x1B #define INT_CTRL1 0x1E #define DATA_CTRL 0x21 /* CONTROL REGISTER 1 BITS */ #define PC1_OFF 0x7F #define PC1_ON (1 << 7) /* Data ready funtion enable bit: set during probe if using irq mode */ #define DRDYE (1 << 5) /* INTERRUPT CONTROL REGISTER 1 BITS */ /* Set these during probe if using irq mode */ #define KXTJ9_IEL (1 << 3) #define KXTJ9_IEA (1 << 4) #define KXTJ9_IEN (1 << 5) /* INPUT_ABS CONSTANTS */ #define FUZZ 3 #define FLAT 3 /* RESUME STATE INDICES */ #define RES_DATA_CTRL 0 #define RES_CTRL_REG1 1 #define RES_INT_CTRL1 2 #define RESUME_ENTRIES 3 /* * The following table lists the maximum appropriate poll interval for each * available output data rate. */ static const struct { unsigned int cutoff; u8 mask; } kxtj9_odr_table[] = { { 3, ODR800F }, { 5, ODR400F }, { 10, ODR200F }, { 20, ODR100F }, { 40, ODR50F }, { 80, ODR25F }, { 0, ODR12_5F}, }; struct kxtj9_data { struct i2c_client *client; struct kxtj9_platform_data pdata; struct input_dev *input_dev; #ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE struct input_polled_dev *poll_dev; #endif unsigned int last_poll_interval; u8 shift; u8 ctrl_reg1; u8 data_ctrl; u8 int_ctrl; }; static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len) { struct i2c_msg msgs[] = { { .addr = tj9->client->addr, .flags = tj9->client->flags, .len = 1, .buf = &addr, }, { .addr = tj9->client->addr, .flags = tj9->client->flags | I2C_M_RD, .len = len, .buf = data, }, }; return i2c_transfer(tj9->client->adapter, msgs, 2); } static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9) { s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */ s16 x, y, z; int err; err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6); if (err < 0) dev_err(&tj9->client->dev, "accelerometer data read failed\n"); x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]) >> tj9->shift; y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]) >> tj9->shift; z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]) >> tj9->shift; input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x); input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y); input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z); input_sync(tj9->input_dev); } static irqreturn_t kxtj9_isr(int irq, void *dev) { struct kxtj9_data *tj9 = dev; int err; /* data ready is the only possible interrupt type */ kxtj9_report_acceleration_data(tj9); err = i2c_smbus_read_byte_data(tj9->client, INT_REL); if (err < 0) dev_err(&tj9->client->dev, "error clearing interrupt status: %d\n", err); return IRQ_HANDLED; } static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range) { switch (new_g_range) { case KXTJ9_G_2G: tj9->shift = 4; break; case KXTJ9_G_4G: tj9->shift = 3; break; case KXTJ9_G_8G: tj9->shift = 2; break; default: return -EINVAL; } tj9->ctrl_reg1 &= 0xe7; tj9->ctrl_reg1 |= new_g_range; return 0; } static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval) { int err; int i; /* Use the lowest ODR that can support the requested poll interval */ for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) { tj9->data_ctrl = kxtj9_odr_table[i].mask; if (poll_interval < kxtj9_odr_table[i].cutoff) break; } err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0); if (err < 0) return err; err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl); if (err < 0) return err; err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1); if (err < 0) return err; return 0; } static int kxtj9_device_power_on(struct kxtj9_data *tj9) { if (tj9->pdata.power_on) return tj9->pdata.power_on(); return 0; } static void kxtj9_device_power_off(struct kxtj9_data *tj9) { int err; tj9->ctrl_reg1 &= PC1_OFF; err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1); if (err < 0) dev_err(&tj9->client->dev, "soft power off failed\n"); if (tj9->pdata.power_off) tj9->pdata.power_off(); } static int kxtj9_enable(struct kxtj9_data *tj9) { int err; err = kxtj9_device_power_on(tj9); if (err < 0) return err; /* ensure that PC1 is cleared before updating control registers */ err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0); if (err < 0) return err; /* only write INT_CTRL_REG1 if in irq mode */ if (tj9->client->irq) { err = i2c_smbus_write_byte_data(tj9->client, INT_CTRL1, tj9->int_ctrl); if (err < 0) return err; } err = kxtj9_update_g_range(tj9, tj9->pdata.g_range); if (err < 0) return err; /* turn on outputs */ tj9->ctrl_reg1 |= PC1_ON; err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1); if (err < 0) return err; err = kxtj9_update_odr(tj9, tj9->last_poll_interval); if (err < 0) return err; /* clear initial interrupt if in irq mode */ if (tj9->client->irq) { err = i2c_smbus_read_byte_data(tj9->client, INT_REL); if (err < 0) { dev_err(&tj9->client->dev, "error clearing interrupt: %d\n", err); goto fail; } } return 0; fail: kxtj9_device_power_off(tj9); return err; } static void kxtj9_disable(struct kxtj9_data *tj9) { kxtj9_device_power_off(tj9); } static int kxtj9_input_open(struct input_dev *input) { struct kxtj9_data *tj9 = input_get_drvdata(input); return kxtj9_enable(tj9); } static void kxtj9_input_close(struct input_dev *dev) { struct kxtj9_data *tj9 = input_get_drvdata(dev); kxtj9_disable(tj9); } static void __devinit kxtj9_init_input_device(struct kxtj9_data *tj9, struct input_dev *input_dev) { __set_bit(EV_ABS, input_dev->evbit); input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT); input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT); input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT); input_dev->name = "kxtj9_accel"; input_dev->id.bustype = BUS_I2C; input_dev->dev.parent = &tj9->client->dev; } static int __devinit kxtj9_setup_input_device(struct kxtj9_data *tj9) { struct input_dev *input_dev; int err; input_dev = input_allocate_device(); if (!input_dev) { dev_err(&tj9->client->dev, "input device allocate failed\n"); return -ENOMEM; } tj9->input_dev = input_dev; input_dev->open = kxtj9_input_open; input_dev->close = kxtj9_input_close; input_set_drvdata(input_dev, tj9); kxtj9_init_input_device(tj9, input_dev); err = input_register_device(tj9->input_dev); if (err) { dev_err(&tj9->client->dev, "unable to register input polled device %s: %d\n", tj9->input_dev->name, err); input_free_device(tj9->input_dev); return err; } return 0; } /* * When IRQ mode is selected, we need to provide an interface to allow the user * to change the output data rate of the part. For consistency, we are using * the set_poll method, which accepts a poll interval in milliseconds, and then * calls update_odr() while passing this value as an argument. In IRQ mode, the * data outputs will not be read AT the requested poll interval, rather, the * lowest ODR that can support the requested interval. The client application * will be responsible for retrieving data from the input node at the desired * interval. */ /* Returns currently selected poll interval (in ms) */ static ssize_t kxtj9_get_poll(struct device *dev, struct device_attribute *attr, char *buf) { struct i2c_client *client = to_i2c_client(dev); struct kxtj9_data *tj9 = i2c_get_clientdata(client); return sprintf(buf, "%d\n", tj9->last_poll_interval); } /* Allow users to select a new poll interval (in ms) */ static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct i2c_client *client = to_i2c_client(dev); struct kxtj9_data *tj9 = i2c_get_clientdata(client); struct input_dev *input_dev = tj9->input_dev; unsigned int interval; int error; error = kstrtouint(buf, 10, &interval); if (error < 0) return error; /* Lock the device to prevent races with open/close (and itself) */ mutex_lock(&input_dev->mutex); disable_irq(client->irq); /* * Set current interval to the greater of the minimum interval or * the requested interval */ tj9->last_poll_interval = max(interval, tj9->pdata.min_interval); kxtj9_update_odr(tj9, tj9->last_poll_interval); enable_irq(client->irq); mutex_unlock(&input_dev->mutex); return count; } static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll); static struct attribute *kxtj9_attributes[] = { &dev_attr_poll.attr, NULL }; static struct attribute_group kxtj9_attribute_group = { .attrs = kxtj9_attributes }; #ifdef CONFIG_INPUT_KXTJ9_POLLED_MODE static void kxtj9_poll(struct input_polled_dev *dev) { struct kxtj9_data *tj9 = dev->private; unsigned int poll_interval = dev->poll_interval; kxtj9_report_acceleration_data(tj9); if (poll_interval != tj9->last_poll_interval) { kxtj9_update_odr(tj9, poll_interval); tj9->last_poll_interval = poll_interval; } } static void kxtj9_polled_input_open(struct input_polled_dev *dev) { struct kxtj9_data *tj9 = dev->private; kxtj9_enable(tj9); } static void kxtj9_polled_input_close(struct input_polled_dev *dev) { struct kxtj9_data *tj9 = dev->private; kxtj9_disable(tj9); } static int __devinit kxtj9_setup_polled_device(struct kxtj9_data *tj9) { int err; struct input_polled_dev *poll_dev; poll_dev = input_allocate_polled_device(); if (!poll_dev) { dev_err(&tj9->client->dev, "Failed to allocate polled device\n"); return -ENOMEM; } tj9->poll_dev = poll_dev; tj9->input_dev = poll_dev->input; poll_dev->private = tj9; poll_dev->poll = kxtj9_poll; poll_dev->open = kxtj9_polled_input_open; poll_dev->close = kxtj9_polled_input_close; kxtj9_init_input_device(tj9, poll_dev->input); err = input_register_polled_device(poll_dev); if (err) { dev_err(&tj9->client->dev, "Unable to register polled device, err=%d\n", err); input_free_polled_device(poll_dev); return err; } return 0; } static void __devexit kxtj9_teardown_polled_device(struct kxtj9_data *tj9) { input_unregister_polled_device(tj9->poll_dev); input_free_polled_device(tj9->poll_dev); } #else static inline int kxtj9_setup_polled_device(struct kxtj9_data *tj9) { return -ENOSYS; } static inline void kxtj9_teardown_polled_device(struct kxtj9_data *tj9) { } #endif static int __devinit kxtj9_verify(struct kxtj9_data *tj9) { int retval; retval = kxtj9_device_power_on(tj9); if (retval < 0) return retval; retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I); if (retval < 0) { dev_err(&tj9->client->dev, "read err int source\n"); goto out; } retval = retval != 0x06 ? -EIO : 0; out: kxtj9_device_power_off(tj9); return retval; } static int __devinit kxtj9_probe(struct i2c_client *client, const struct i2c_device_id *id) { const struct kxtj9_platform_data *pdata = client->dev.platform_data; struct kxtj9_data *tj9; int err; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) { dev_err(&client->dev, "client is not i2c capable\n"); return -ENXIO; } if (!pdata) { dev_err(&client->dev, "platform data is NULL; exiting\n"); return -EINVAL; } tj9 = kzalloc(sizeof(*tj9), GFP_KERNEL); if (!tj9) { dev_err(&client->dev, "failed to allocate memory for module data\n"); return -ENOMEM; } tj9->client = client; tj9->pdata = *pdata; if (pdata->init) { err = pdata->init(); if (err < 0) goto err_free_mem; } err = kxtj9_verify(tj9); if (err < 0) { dev_err(&client->dev, "device not recognized\n"); goto err_pdata_exit; } i2c_set_clientdata(client, tj9); tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range; tj9->data_ctrl = tj9->pdata.data_odr_init; if (client->irq) { /* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */ tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL; tj9->ctrl_reg1 |= DRDYE; err = kxtj9_setup_input_device(tj9); if (err) goto err_pdata_exit; err = request_threaded_irq(client->irq, NULL, kxtj9_isr, IRQF_TRIGGER_RISING | IRQF_ONESHOT, "kxtj9-irq", tj9); if (err) { dev_err(&client->dev, "request irq failed: %d\n", err); goto err_destroy_input; } err = sysfs_create_group(&client->dev.kobj, &kxtj9_attribute_group); if (err) { dev_err(&client->dev, "sysfs create failed: %d\n", err); goto err_free_irq; } } else { err = kxtj9_setup_polled_device(tj9); if (err) goto err_pdata_exit; } return 0; err_free_irq: free_irq(client->irq, tj9); err_destroy_input: input_unregister_device(tj9->input_dev); err_pdata_exit: if (tj9->pdata.exit) tj9->pdata.exit(); err_free_mem: kfree(tj9); return err; } static int __devexit kxtj9_remove(struct i2c_client *client) { struct kxtj9_data *tj9 = i2c_get_clientdata(client); if (client->irq) { sysfs_remove_group(&client->dev.kobj, &kxtj9_attribute_group); free_irq(client->irq, tj9); input_unregister_device(tj9->input_dev); } else { kxtj9_teardown_polled_device(tj9); } if (tj9->pdata.exit) tj9->pdata.exit(); kfree(tj9); return 0; } #ifdef CONFIG_PM_SLEEP static int kxtj9_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct kxtj9_data *tj9 = i2c_get_clientdata(client); struct input_dev *input_dev = tj9->input_dev; mutex_lock(&input_dev->mutex); if (input_dev->users) kxtj9_disable(tj9); mutex_unlock(&input_dev->mutex); return 0; } static int kxtj9_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct kxtj9_data *tj9 = i2c_get_clientdata(client); struct input_dev *input_dev = tj9->input_dev; int retval = 0; mutex_lock(&input_dev->mutex); if (input_dev->users) kxtj9_enable(tj9); mutex_unlock(&input_dev->mutex); return retval; } #endif static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume); static const struct i2c_device_id kxtj9_id[] = { { NAME, 0 }, { }, }; MODULE_DEVICE_TABLE(i2c, kxtj9_id); static struct i2c_driver kxtj9_driver = { .driver = { .name = NAME, .owner = THIS_MODULE, .pm = &kxtj9_pm_ops, }, .probe = kxtj9_probe, .remove = __devexit_p(kxtj9_remove), .id_table = kxtj9_id, }; static int __init kxtj9_init(void) { return i2c_add_driver(&kxtj9_driver); } module_init(kxtj9_init); static void __exit kxtj9_exit(void) { i2c_del_driver(&kxtj9_driver); } module_exit(kxtj9_exit); MODULE_DESCRIPTION("KXTJ9 accelerometer driver"); MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>"); MODULE_LICENSE("GPL");