diff options
Diffstat (limited to 'drivers/mfd/da9052-i2c.c')
| -rw-r--r-- | drivers/mfd/da9052-i2c.c | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/drivers/mfd/da9052-i2c.c b/drivers/mfd/da9052-i2c.c new file mode 100644 index 00000000000..dba23f16188 --- /dev/null +++ b/drivers/mfd/da9052-i2c.c @@ -0,0 +1,379 @@ +/* + * Copyright(c) 2009 Dialog Semiconductor Ltd. + * + * 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. + * + * da9052-i2c.c: I2C SSC (Synchronous Serial Communication) driver for DA9052 + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/mfd/core.h> +#include <linux/i2c.h> +#include <linux/mfd/da9052/da9052.h> +#include <linux/mfd/da9052/reg.h> + +static struct da9052 *da9052_i2c; + +#define I2C_CONNECTED 0 + +static int da9052_i2c_is_connected(void) +{ + + struct da9052_ssc_msg msg; + + /* printk("Entered da9052_i2c_is_connected.............\n"); */ + + msg.addr = DA9052_INTERFACE_REG; + + /* Test spi connectivity by performing read of the GPIO_0-1 register */ + if (0 != da9052_i2c_read(da9052_i2c, &msg)) { + printk(KERN_DEBUG "da9052_i2c_is_connected - "\ + "i2c read failed.............\n"); + return -1; + } else { + printk(KERN_DEBUG "da9052_i2c_is_connected - "\ + "i2c read success..............\n"); + return 0; + } + +} + +static int __devinit da9052_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter; + /* printk("\n\tEntered da9052_i2c_is_probe.............\n"); */ + + da9052_i2c = kzalloc(sizeof(struct da9052), GFP_KERNEL); + + if (!da9052_i2c) + return -ENOMEM; + + /* Get the bus driver handler */ + adapter = to_i2c_adapter(client->dev.parent); + + /* Check i2c bus driver supports byte data transfer */ + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) { + dev_info(&client->dev,\ + "Error in %s:i2c_check_functionality\n", __func__); + return -ENODEV; + } + + /* Store handle to i2c client */ + da9052_i2c->i2c_client = client; + da9052_i2c->irq = client->irq; + + da9052_i2c->dev = &client->dev; + + /* Initialize i2c data structure here*/ + da9052_i2c->adapter = adapter; + + /* host i2c driver looks only first 7 bits for the slave address */ + da9052_i2c->slave_addr = DA9052_I2C_ADDR >> 1; + + /* Store the i2c client data */ + i2c_set_clientdata(client, da9052_i2c); + + /* Validate I2C connectivity */ + if (I2C_CONNECTED == da9052_i2c_is_connected()) { + /* I2C is connected */ + da9052_i2c->connecting_device = I2C; + if (0 != da9052_ssc_init(da9052_i2c)) + return -ENODEV; + } else { + return -ENODEV; + } + + /* printk("Exiting da9052_i2c_probe.....\n"); */ + + return 0; +} + +static int da9052_i2c_remove(struct i2c_client *client) +{ + + struct da9052 *da9052 = i2c_get_clientdata(client); + + mfd_remove_devices(da9052->dev); + kfree(da9052); + return 0; +} + +int da9052_i2c_write(struct da9052 *da9052, struct da9052_ssc_msg *msg) +{ + struct i2c_msg i2cmsg; + unsigned char buf[2] = {0}; + int ret = 0; + + /* Copy the ssc msg to local character buffer */ + buf[0] = msg->addr; + buf[1] = msg->data; + + /*Construct a i2c msg for a da9052 driver ssc message request */ + i2cmsg.addr = da9052->slave_addr; + i2cmsg.len = 2; + i2cmsg.buf = buf; + + /* To write the data on I2C set flag to zero */ + i2cmsg.flags = 0; + + /* Start the i2c transfer by calling host i2c driver function */ + ret = i2c_transfer(da9052->adapter, &i2cmsg, 1); + + if (ret < 0) { + dev_info(&da9052->i2c_client->dev,\ + "_%s:master_xfer Failed!!\n", __func__); + return ret; + } + + return 0; +} + +int da9052_i2c_read(struct da9052 *da9052, struct da9052_ssc_msg *msg) +{ + + /*Get the da9052_i2c client details*/ + unsigned char buf[2] = {0, 0}; + struct i2c_msg i2cmsg[2]; + int ret = 0; + + /* Copy SSC Msg to local character buffer */ + buf[0] = msg->addr; + + /*Construct a i2c msg for a da9052 driver ssc message request */ + i2cmsg[0].addr = da9052->slave_addr ; + i2cmsg[0].len = 1; + i2cmsg[0].buf = &buf[0]; + + /*To write the data on I2C set flag to zero */ + i2cmsg[0].flags = 0; + + /* Read the data from da9052*/ + /*Construct a i2c msg for a da9052 driver ssc message request */ + i2cmsg[1].addr = da9052->slave_addr ; + i2cmsg[1].len = 1; + i2cmsg[1].buf = &buf[1]; + + /*To read the data on I2C set flag to I2C_M_RD */ + i2cmsg[1].flags = I2C_M_RD; + + /* Start the i2c transfer by calling host i2c driver function */ + ret = i2c_transfer(da9052->adapter, i2cmsg, 2); + if (ret < 0) { + dev_info(&da9052->i2c_client->dev,\ + "2 - %s:master_xfer Failed!!\n", __func__); + return ret; + } + + msg->data = *i2cmsg[1].buf; + + return 0; +} + +int da9052_i2c_write_many(struct da9052 *da9052, + struct da9052_ssc_msg *sscmsg, int msg_no) +{ + + struct i2c_msg i2cmsg; + unsigned char data_buf[MAX_READ_WRITE_CNT+1]; + struct da9052_ssc_msg ctrlb_msg; + struct da9052_ssc_msg *msg_queue = sscmsg; + int ret = 0; + /* Flag to check if requested registers are contiguous */ + unsigned char cont_data = 1; + unsigned char cnt = 0; + + /* Check if requested registers are contiguous */ + for (cnt = 1; cnt < msg_no; cnt++) { + if ((msg_queue[cnt].addr - msg_queue[cnt-1].addr) != 1) { + /* Difference is not 1, i.e. non-contiguous registers */ + cont_data = 0; + break; + } + } + + if (cont_data == 0) { + /* Requested registers are non-contiguous */ + for (cnt = 0; cnt < msg_no; cnt++) { + ret = da9052->write(da9052, &msg_queue[cnt]); + if (ret != 0) + return ret; + } + return 0; + } + /* + * Requested registers are contiguous + * or PAGE WRITE sequence of I2C transactions is as below + * (slave_addr + reg_addr + data_1 + data_2 + ...) + * First read current WRITE MODE via CONTROL_B register of DA9052 + */ + ctrlb_msg.addr = DA9052_CONTROLB_REG; + ctrlb_msg.data = 0x0; + ret = da9052->read(da9052, &ctrlb_msg); + + if (ret != 0) + return ret; + + /* Check if PAGE WRITE mode is set */ + if (ctrlb_msg.data & DA9052_CONTROLB_WRITEMODE) { + /* REPEAT WRITE mode is configured */ + /* Now set DA9052 into PAGE WRITE mode */ + ctrlb_msg.data &= ~DA9052_CONTROLB_WRITEMODE; + ret = da9052->write(da9052, &ctrlb_msg); + + if (ret != 0) + return ret; + } + + /* Put first register address */ + data_buf[0] = msg_queue[0].addr; + + for (cnt = 0; cnt < msg_no; cnt++) + data_buf[cnt+1] = msg_queue[cnt].data; + + /* Construct a i2c msg for PAGE WRITE */ + i2cmsg.addr = da9052->slave_addr ; + /* First register address + all data*/ + i2cmsg.len = (msg_no + 1); + i2cmsg.buf = data_buf; + + /*To write the data on I2C set flag to zero */ + i2cmsg.flags = 0; + + /* Start the i2c transfer by calling host i2c driver function */ + ret = i2c_transfer(da9052->adapter, &i2cmsg, 1); + if (ret < 0) { + dev_info(&da9052->i2c_client->dev,\ + "1 - i2c_transfer function falied in [%s]!!!\n", __func__); + return ret; + } + + return 0; +} + +int da9052_i2c_read_many(struct da9052 *da9052, + struct da9052_ssc_msg *sscmsg, int msg_no) +{ + + struct i2c_msg i2cmsg; + unsigned char data_buf[MAX_READ_WRITE_CNT]; + struct da9052_ssc_msg *msg_queue = sscmsg; + int ret = 0; + /* Flag to check if requested registers are contiguous */ + unsigned char cont_data = 1; + unsigned char cnt = 0; + + /* Check if requested registers are contiguous */ + for (cnt = 1; cnt < msg_no; cnt++) { + if ((msg_queue[cnt].addr - msg_queue[cnt-1].addr) != 1) { + /* Difference is not 1, i.e. non-contiguous registers */ + cont_data = 0; + break; + } + } + + if (cont_data == 0) { + /* Requested registers are non-contiguous */ + for (cnt = 0; cnt < msg_no; cnt++) { + ret = da9052->read(da9052, &msg_queue[cnt]); + if (ret != 0) { + dev_info(&da9052->i2c_client->dev,\ + "Error in %s", __func__); + return ret; + } + } + return 0; + } + + /* + * We want to perform PAGE READ via I2C + * For PAGE READ sequence of I2C transactions is as below + * (slave_addr + reg_addr) + (slave_addr + data_1 + data_2 + ...) + */ + /* Copy address of first register */ + data_buf[0] = msg_queue[0].addr; + + /* Construct a i2c msg for first transaction of PAGE READ i.e. write */ + i2cmsg.addr = da9052->slave_addr ; + i2cmsg.len = 1; + i2cmsg.buf = data_buf; + + /*To write the data on I2C set flag to zero */ + i2cmsg.flags = 0; + + /* Start the i2c transfer by calling host i2c driver function */ + ret = i2c_transfer(da9052->adapter, &i2cmsg, 1); + if (ret < 0) { + dev_info(&da9052->i2c_client->dev,\ + "1 - i2c_transfer function falied in [%s]!!!\n", __func__); + return ret; + } + + /* Now Read the data from da9052 */ + /* Construct a i2c msg for second transaction of PAGE READ i.e. read */ + i2cmsg.addr = da9052->slave_addr ; + i2cmsg.len = msg_no; + i2cmsg.buf = data_buf; + + /*To read the data on I2C set flag to I2C_M_RD */ + i2cmsg.flags = I2C_M_RD; + + /* Start the i2c transfer by calling host i2c driver function */ + ret = i2c_transfer(da9052->adapter, + &i2cmsg, 1); + if (ret < 0) { + dev_info(&da9052->i2c_client->dev,\ + "2 - i2c_transfer function falied in [%s]!!!\n", __func__); + return ret; + } + + /* Gather READ data */ + for (cnt = 0; cnt < msg_no; cnt++) + sscmsg[cnt].data = data_buf[cnt]; + + return 0; +} + +static struct i2c_device_id da9052_ssc_id[] = { + { DA9052_SSC_I2C_DEVICE_NAME, 0}, + {} +}; + +static struct i2c_driver da9052_i2c_driver = { + .driver = { + .name = DA9052_SSC_I2C_DEVICE_NAME, + .owner = THIS_MODULE, + }, + .probe = da9052_i2c_probe, + .remove = da9052_i2c_remove, + .id_table = da9052_ssc_id, +}; + +static int __init da9052_i2c_init(void) +{ + int ret = 0; + /* printk("\n\nEntered da9052_i2c_init................\n\n"); */ + ret = i2c_add_driver(&da9052_i2c_driver); + if (ret != 0) { + printk(KERN_ERR "Unable to register %s\n", + DA9052_SSC_I2C_DEVICE_NAME); + return ret; + } + return 0; +} +subsys_initcall(da9052_i2c_init); + +static void __exit da9052_i2c_exit(void) +{ + i2c_del_driver(&da9052_i2c_driver); +} +module_exit(da9052_i2c_exit); + +MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>"); +MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DA9052_SSC_I2C_DEVICE_NAME); |