diff options
Diffstat (limited to 'drivers/input/misc/adxl34x-spi.c')
| -rw-r--r-- | drivers/input/misc/adxl34x-spi.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/drivers/input/misc/adxl34x-spi.c b/drivers/input/misc/adxl34x-spi.c new file mode 100644 index 000000000000..782de9e89828 --- /dev/null +++ b/drivers/input/misc/adxl34x-spi.c @@ -0,0 +1,145 @@ +/* + * ADLX345/346 Three-Axis Digital Accelerometers (SPI Interface) + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Copyright (C) 2009 Michael Hennerich, Analog Devices Inc. + * Licensed under the GPL-2 or later. + */ + +#include <linux/input.h> /* BUS_SPI */ +#include <linux/module.h> +#include <linux/spi/spi.h> +#include <linux/types.h> +#include "adxl34x.h" + +#define MAX_SPI_FREQ_HZ 5000000 +#define MAX_FREQ_NO_FIFODELAY 1500000 +#define ADXL34X_CMD_MULTB (1 << 6) +#define ADXL34X_CMD_READ (1 << 7) +#define ADXL34X_WRITECMD(reg) (reg & 0x3F) +#define ADXL34X_READCMD(reg) (ADXL34X_CMD_READ | (reg & 0x3F)) +#define ADXL34X_READMB_CMD(reg) (ADXL34X_CMD_READ | ADXL34X_CMD_MULTB \ + | (reg & 0x3F)) + +static int adxl34x_spi_read(struct device *dev, unsigned char reg) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned char cmd; + + cmd = ADXL34X_READCMD(reg); + + return spi_w8r8(spi, cmd); +} + +static int adxl34x_spi_write(struct device *dev, + unsigned char reg, unsigned char val) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned char buf[2]; + + buf[0] = ADXL34X_WRITECMD(reg); + buf[1] = val; + + return spi_write(spi, buf, sizeof(buf)); +} + +static int adxl34x_spi_read_block(struct device *dev, + unsigned char reg, int count, + void *buf) +{ + struct spi_device *spi = to_spi_device(dev); + ssize_t status; + + reg = ADXL34X_READMB_CMD(reg); + status = spi_write_then_read(spi, ®, 1, buf, count); + + return (status < 0) ? status : 0; +} + +static const struct adxl34x_bus_ops adx134x_spi_bops = { + .bustype = BUS_SPI, + .write = adxl34x_spi_write, + .read = adxl34x_spi_read, + .read_block = adxl34x_spi_read_block, +}; + +static int __devinit adxl34x_spi_probe(struct spi_device *spi) +{ + struct adxl34x *ac; + + /* don't exceed max specified SPI CLK frequency */ + if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { + dev_err(&spi->dev, "SPI CLK %d Hz too fast\n", spi->max_speed_hz); + return -EINVAL; + } + + ac = adxl34x_probe(&spi->dev, spi->irq, + spi->max_speed_hz > MAX_FREQ_NO_FIFODELAY, + &adx134x_spi_bops); + + if (IS_ERR(ac)) + return PTR_ERR(ac); + + spi_set_drvdata(spi, ac); + + return 0; +} + +static int __devexit adxl34x_spi_remove(struct spi_device *spi) +{ + struct adxl34x *ac = dev_get_drvdata(&spi->dev); + + return adxl34x_remove(ac); +} + +#ifdef CONFIG_PM +static int adxl34x_spi_suspend(struct spi_device *spi, pm_message_t message) +{ + struct adxl34x *ac = dev_get_drvdata(&spi->dev); + + adxl34x_suspend(ac); + + return 0; +} + +static int adxl34x_spi_resume(struct spi_device *spi) +{ + struct adxl34x *ac = dev_get_drvdata(&spi->dev); + + adxl34x_resume(ac); + + return 0; +} +#else +# define adxl34x_spi_suspend NULL +# define adxl34x_spi_resume NULL +#endif + +static struct spi_driver adxl34x_driver = { + .driver = { + .name = "adxl34x", + .bus = &spi_bus_type, + .owner = THIS_MODULE, + }, + .probe = adxl34x_spi_probe, + .remove = __devexit_p(adxl34x_spi_remove), + .suspend = adxl34x_spi_suspend, + .resume = adxl34x_spi_resume, +}; + +static int __init adxl34x_spi_init(void) +{ + return spi_register_driver(&adxl34x_driver); +} +module_init(adxl34x_spi_init); + +static void __exit adxl34x_spi_exit(void) +{ + spi_unregister_driver(&adxl34x_driver); +} +module_exit(adxl34x_spi_exit); + +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); +MODULE_DESCRIPTION("ADXL345/346 Three-Axis Digital Accelerometer SPI Bus Driver"); +MODULE_LICENSE("GPL"); |