diff options
Diffstat (limited to 'drivers/mfd/da9052-spi.c')
-rw-r--r-- | drivers/mfd/da9052-spi.c | 399 |
1 files changed, 399 insertions, 0 deletions
diff --git a/drivers/mfd/da9052-spi.c b/drivers/mfd/da9052-spi.c new file mode 100644 index 000000000000..9dd90c2d19f9 --- /dev/null +++ b/drivers/mfd/da9052-spi.c @@ -0,0 +1,399 @@ +/* + * 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-spi.c: SPI SSC (Synchronous Serial Communication) driver for DA9052 + */ + +#include <linux/device.h> +#include <linux/mfd/core.h> +#include <linux/spi/spi.h> +#include <linux/mfd/da9052/da9052.h> +#include <linux/mfd/da9052/reg.h> + + +struct da9052 *da9052_spi; + +#define SPI_CONNECTED 0 + +static int da9052_spi_is_connected(void) +{ + + struct da9052_ssc_msg msg; + + //printk("Entered da9052_spi_is_connected.............\n"); + + msg.addr = DA9052_INTERFACE_REG; + + /* Test spi connectivity by performing read of the GPIO_0-1 register and then verify the read value*/ + if ( 0 != da9052_spi_read(da9052_spi, &msg)) { + printk("da9052_spi_is_connected - spi read failed.............\n"); + return -1; + } + else if( 0x88 != msg.data ){ + printk("da9052_spi_is_connected - spi read failed. Msg data =%x ..............\n",msg.data); + return -1; + } + + return 0; + +} + +static int da9052_spi_probe(struct spi_device *spi) +{ + //printk("\n\tEntered da9052_spi_probe.....\n"); + + da9052_spi = kzalloc(sizeof(struct da9052), GFP_KERNEL); + + if (!da9052_spi) + return -ENOMEM; + + + spi->mode = SPI_MODE_0 | SPI_CPOL; + spi->bits_per_word = 8; + spi_setup(spi); + + da9052_spi->dev = &spi->dev; + + da9052_spi->spi_dev = spi; + + /* + * Allocate memory for RX/TX bufferes used in single register read/write + */ + da9052_spi->spi_rx_buf = kmalloc(2, GFP_KERNEL | GFP_DMA); + if (!da9052_spi->spi_rx_buf) + return -ENOMEM; + + da9052_spi->spi_tx_buf = kmalloc(2, GFP_KERNEL | GFP_DMA); + if (!da9052_spi->spi_tx_buf) + return -ENOMEM; + + da9052_spi->spi_active_page = PAGECON_0; + da9052_spi->rw_pol = 1; + + + dev_set_drvdata(&spi->dev, da9052_spi); + + + /* Validate SPI connectivity */ + if ( SPI_CONNECTED == da9052_spi_is_connected()) { + /* SPI is connected */ + da9052_spi->connecting_device = SPI; + if( 0 != da9052_ssc_init(da9052_spi) ) + return -ENODEV; + } + else { + return -ENODEV; + } + + //printk("Exiting da9052_spi_probe.....\n"); + + return 0; +} + +static int da9052_spi_remove(struct spi_device *spi) +{ + struct da9052 *da9052 = dev_get_drvdata(&spi->dev); + + printk("Entered da9052_spi_remove()\n"); + if(SPI == da9052->connecting_device ) { + da9052_ssc_exit(da9052); + } + mfd_remove_devices(&spi->dev); + kfree(da9052->spi_rx_buf); + kfree(da9052->spi_tx_buf); + kfree(da9052); + return 0; +} + +static struct spi_driver da9052_spi_driver = { + .driver = { + .name = DA9052_SSC_SPI_DEVICE_NAME, + .bus = &spi_bus_type, + .owner = THIS_MODULE, + }, + .probe = da9052_spi_probe, + .remove = __devexit_p(da9052_spi_remove), +}; + + +static int da9052_spi_set_page(struct da9052 *da9052, unsigned char page) +{ + + struct da9052_ssc_msg sscmsg; + struct spi_message message; + struct spi_transfer xfer; + int ret = 0; + + printk("Entered da9052_spi_set_page.....\n"); + if ((page != PAGECON_0) && ((page != PAGECON_128))) + return INVALID_PAGE; + + /* Current configuration is PAGE-0 and write request for PAGE-1 */ + /* set register address */ + sscmsg.addr = DA9052_PAGECON0_REG; + /* set value */ + sscmsg.data = page; + + /* Check value of R/W_POL bit of INTERFACE register */ + if (!da9052->rw_pol) { + /* We need to set 0th bit for write operation */ + sscmsg.addr = ((sscmsg.addr << 1) | RW_POL); + } else { + /* We need to reset 0th bit for write operation */ + sscmsg.addr = (sscmsg.addr << 1); + } + + /* SMDK-6410 host SPI driver specific stuff */ + + /* Build our spi message */ + printk("da9052_spi_set_page - Calling spi_message_init.....\n"); + spi_message_init(&message); + memset(&xfer, 0, sizeof(xfer)); + + xfer.len = 2; + xfer.tx_buf = da9052->spi_tx_buf; + xfer.rx_buf = da9052->spi_rx_buf; + + da9052->spi_tx_buf[0] = sscmsg.addr; + da9052->spi_tx_buf[1] = sscmsg.data; + + printk("da9052_spi_set_page - Calling spi_message_add_tail.....\n"); + spi_message_add_tail(&xfer, &message); + + /* Now, do the i/o */ + printk("da9052_spi_set_page - Calling spi_sync.....\n"); + ret = spi_sync(da9052->spi_dev, &message); + + if (ret == 0) { + /* Active Page set successfully */ + da9052->spi_active_page = page; + return 0; + } else { + /* Error in setting Active Page */ + return ret; + } + + return 0; +} + +int da9052_spi_write(struct da9052 *da9052, struct da9052_ssc_msg *msg) +{ + + struct spi_message message; + struct spi_transfer xfer; + int ret; + + /* + * We need a seperate copy of da9052_ssc_msg so that caller's + * copy remains intact + */ + struct da9052_ssc_msg sscmsg; + + /* Copy callers data in to our local copy */ + sscmsg.addr = msg->addr; + sscmsg.data = msg->data; + + if ((sscmsg.addr > PAGE_0_END) && + (da9052->spi_active_page == PAGECON_0)) { + /* + * Current configuration is PAGE-0 and write request + * for PAGE-1 + */ + da9052_spi_set_page(da9052, PAGECON_128); + /* Set register address accordindly */ + sscmsg.addr = (sscmsg.addr - PAGE_1_START); + } else if ((sscmsg.addr < PAGE_1_START) && + (da9052->spi_active_page == PAGECON_128)) { + /* + * Current configuration is PAGE-1 and write request + * for PAGE-0 + */ + da9052_spi_set_page(da9052, PAGECON_0); + } else if (sscmsg.addr > PAGE_0_END) { + /* + * Current configuration is PAGE-1 and write request + * for PAGE-1. Just need to adjust register address + */ + sscmsg.addr = (sscmsg.addr - PAGE_1_START); + } + + /* Check value of R/W_POL bit of INTERFACE register */ + if (!da9052->rw_pol) { + /* We need to set 0th bit for write operation */ + sscmsg.addr = ((sscmsg.addr << 1) | RW_POL); + } else { + /* We need to reset 0th bit for write operation */ + sscmsg.addr = (sscmsg.addr << 1); + } + + /* SMDK-6410 host SPI driver specific stuff */ + + /* Build our spi message */ + spi_message_init(&message); + memset(&xfer, 0, sizeof(xfer)); + + xfer.len = 2; + xfer.tx_buf = da9052->spi_tx_buf; + xfer.rx_buf = da9052->spi_rx_buf; + + da9052->spi_tx_buf[0] = sscmsg.addr; + da9052->spi_tx_buf[1] = sscmsg.data; + + spi_message_add_tail(&xfer, &message); + + /* Now, do the i/o */ + ret = spi_sync(da9052->spi_dev, &message); + + return ret; +} + +int da9052_spi_write_many(struct da9052 *da9052, struct da9052_ssc_msg *sscmsg, + int msg_no) +{ + int cnt,ret=0; + + for(cnt = 0; cnt < msg_no; cnt++, sscmsg++) { + ret = da9052_ssc_write(da9052,sscmsg); + if(ret != 0) + { + printk("Error in %s", __FUNCTION__); + return -EIO; + } + } + + return 0; +} + +int da9052_spi_read(struct da9052 *da9052, struct da9052_ssc_msg *msg) +{ + + struct spi_message message; + struct spi_transfer xfer; + int ret; + + /* + * We need a seperate copy of da9052_ssc_msg so that + * caller's copy remains intact + */ + struct da9052_ssc_msg sscmsg; + + + /* Copy callers data in to our local copy */ + sscmsg.addr = msg->addr; + sscmsg.data = msg->data; + + if ((sscmsg.addr > PAGE_0_END) && + (da9052->spi_active_page == PAGECON_0)) { + /* + * Current configuration is PAGE-0 and + * read request for PAGE-1 + */ + printk("da9052_spi_read - if PAGECON_128.....\n"); + da9052_spi_set_page(da9052, PAGECON_128); + /* Set register address accordindly */ + sscmsg.addr = (sscmsg.addr - PAGE_1_START); + } else if ((sscmsg.addr < PAGE_1_START) && + (da9052->spi_active_page == PAGECON_128)) { + /* + * Current configuration is PAGE-1 and + * write request for PAGE-0 + */ + printk("da9052_spi_read - if PAGECON_0.....\n"); + da9052_spi_set_page(da9052, PAGECON_0); + } else if (sscmsg.addr > PAGE_0_END) { + /* + * Current configuration is PAGE-1 and write + * request for PAGE-1 + * Just need to adjust register address + */ + sscmsg.addr = (sscmsg.addr - PAGE_1_START); + } + + /* Check value of R/W_POL bit of INTERFACE register */ + if (da9052->rw_pol) { + /* We need to set 0th bit for read operation */ + sscmsg.addr = ((sscmsg.addr << 1) | RW_POL); + } else { + /* We need to reset 0th bit for write operation */ + sscmsg.addr = (sscmsg.addr << 1); + } + + /* SMDK-6410 host SPI driver specific stuff */ + + /* Build our spi message */ + spi_message_init(&message); + memset(&xfer, 0, sizeof(xfer)); + + xfer.len = 2; + xfer.tx_buf = da9052->spi_tx_buf; + xfer.rx_buf = da9052->spi_rx_buf; + + da9052->spi_tx_buf[0] = sscmsg.addr; + da9052->spi_tx_buf[1] = 0xff; + + da9052->spi_rx_buf[0] = 0; + da9052->spi_rx_buf[1] = 0; + + spi_message_add_tail(&xfer, &message); + + /* Now, do the i/o */ + ret = spi_sync(da9052->spi_dev, &message); + + if (ret == 0) { + /* Update read value in callers copy */ + msg->data = da9052->spi_rx_buf[1]; + return 0; + } else { + return ret; + } + + + return 0; +} + +int da9052_spi_read_many(struct da9052 *da9052, struct da9052_ssc_msg *sscmsg, + int msg_no) +{ + int cnt,ret=0; + + for(cnt = 0; cnt < msg_no; cnt++, sscmsg++) { + ret = da9052_ssc_read(da9052,sscmsg); + if(ret != 0) + { + printk("Error in %s", __FUNCTION__); + return -EIO; + } + } + + return 0; +} + +static int __init da9052_spi_init(void) +{ + int ret = 0; + //printk("Entered da9052_spi_init.....\n"); + ret = spi_register_driver(&da9052_spi_driver); + if (ret != 0) { + printk(KERN_ERR "Unable to register %s\n", DA9052_SSC_SPI_DEVICE_NAME); + return ret; + } + return 0; +} +module_init(da9052_spi_init); + +static void __exit da9052_spi_exit(void) +{ + spi_unregister_driver(&da9052_spi_driver); +} + +module_exit(da9052_spi_exit); + +MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>"); +MODULE_DESCRIPTION("SPI driver for Dialog DA9052 PMIC"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DA9052_SSC_SPI_DEVICE_NAME); |