From ffd7a62f0dffa92409dc769562a4997eb424a7d3 Mon Sep 17 00:00:00 2001 From: Graf Yang Date: Wed, 27 Oct 2010 21:44:20 -0400 Subject: [PATCH] staging: iio: resolver: new driver for AD2S1200/1205 devices Signed-off-by: Graf Yang Signed-off-by: Michael Hennerich Acked-by: Jonathan Cameron Signed-off-by: Mike Frysinger Signed-off-by: Greg Kroah-Hartman --- drivers/staging/iio/resolver/Kconfig | 8 + drivers/staging/iio/resolver/Makefile | 1 + drivers/staging/iio/resolver/ad2s120x.c | 310 ++++++++++++++++++++++++++++++++ 3 files changed, 319 insertions(+) create mode 100644 drivers/staging/iio/resolver/ad2s120x.c diff --git a/drivers/staging/iio/resolver/Kconfig b/drivers/staging/iio/resolver/Kconfig index 05b15a9..32df73a 100644 --- a/drivers/staging/iio/resolver/Kconfig +++ b/drivers/staging/iio/resolver/Kconfig @@ -9,3 +9,11 @@ config AD2S90 help Say yes here to build support for Analog Devices spi resolver to digital converters, ad2s90, provides direct access via sysfs. + +config AD2S120X + tristate "Analog Devices ad2s120x driver" + depends on SPI + help + Say yes here to build support for Analog Devices spi resolver + to digital converters, ad2s1200 and ad2s1205, provides direct access + via sysfs. diff --git a/drivers/staging/iio/resolver/Makefile b/drivers/staging/iio/resolver/Makefile index 067fa70..b2b3cc1 100644 --- a/drivers/staging/iio/resolver/Makefile +++ b/drivers/staging/iio/resolver/Makefile @@ -3,3 +3,4 @@ # obj-$(CONFIG_AD2S90) += ad2s90.o +obj-$(CONFIG_AD2S120X) += ad2s120x.o diff --git a/drivers/staging/iio/resolver/ad2s120x.c b/drivers/staging/iio/resolver/ad2s120x.c new file mode 100644 index 0000000..8f497a2 --- /dev/null +++ b/drivers/staging/iio/resolver/ad2s120x.c @@ -0,0 +1,310 @@ +/* + * ad2s120x.c simple support for the ADI Resolver to Digital Converters: AD2S1200/1205 + * + * Copyright (c) 2010-2010 Analog Devices Inc. + * + * 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. + * + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../iio.h" +#include "../sysfs.h" + +#define DRV_NAME "ad2s120x" + +/* input pin sample and rdvel is controlled by driver */ +#define AD2S120X_PN 2 + +/* input clock on serial interface */ +#define AD2S120X_HZ 8192000 +/* clock period in nano second */ +#define AD2S120X_TSCLK (1000000000/AD2S120X_HZ) + +struct ad2s120x_state { + struct mutex lock; + struct iio_dev *idev; + struct spi_device *sdev; + unsigned short sample; + unsigned short rdvel; + u8 rx[2]; + u8 tx[2]; +}; + +static ssize_t ad2s120x_show_pos_vel(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct spi_message msg; + struct spi_transfer xfer; + int ret = 0; + ssize_t len = 0; + u16 pos; + s16 vel; + u8 status; + struct iio_dev *idev = dev_get_drvdata(dev); + struct ad2s120x_state *st = idev->dev_data; + + xfer.len = 1; + xfer.tx_buf = st->tx; + xfer.rx_buf = st->rx; + mutex_lock(&st->lock); + + gpio_set_value(st->sample, 0); + /* delay (6 * AD2S120X_TSCLK + 20) nano seconds */ + udelay(1); + gpio_set_value(st->sample, 1); + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + ret = spi_sync(st->sdev, &msg); + if (ret) + goto error_ret; + status = st->rx[1]; + pos = (((u16)(st->rx[0])) << 4) | ((st->rx[1] & 0xF0) >> 4); + len = sprintf(buf, "%d %c%c%c%c ", pos, + (status & 0x8) ? 'P' : 'V', + (status & 0x4) ? 'd' : '_', + (status & 0x2) ? 'l' : '_', + (status & 0x1) ? '1' : '0'); + + /* delay 18 ns */ + /* ndelay(18); */ + + gpio_set_value(st->rdvel, 0); + /* ndelay(5);*/ + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + ret = spi_sync(st->sdev, &msg); + if (ret) + goto error_ret; + status = st->rx[1]; + vel = (st->rx[0] & 0x80) ? 0xf000 : 0; + vel |= (((s16)(st->rx[0])) << 4) | ((st->rx[1] & 0xF0) >> 4); + len += sprintf(buf + len, "%d %c%c%c%c\n", vel, + (status & 0x8) ? 'P' : 'V', + (status & 0x4) ? 'd' : '_', + (status & 0x2) ? 'l' : '_', + (status & 0x1) ? '1' : '0'); +error_ret: + gpio_set_value(st->rdvel, 1); + /* delay (2 * AD2S120X_TSCLK + 20) ns for sample pulse */ + udelay(1); + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static ssize_t ad2s120x_show_pos(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct spi_message msg; + struct spi_transfer xfer; + int ret = 0; + ssize_t len = 0; + u16 pos; + u8 status; + struct iio_dev *idev = dev_get_drvdata(dev); + struct ad2s120x_state *st = idev->dev_data; + + xfer.len = 1; + xfer.tx_buf = st->tx; + xfer.rx_buf = st->rx; + mutex_lock(&st->lock); + + gpio_set_value(st->sample, 0); + /* delay (6 * AD2S120X_TSCLK + 20) nano seconds */ + udelay(1); + gpio_set_value(st->sample, 1); + gpio_set_value(st->rdvel, 1); + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + ret = spi_sync(st->sdev, &msg); + if (ret) + goto error_ret; + status = st->rx[1]; + pos = (((u16)(st->rx[0])) << 4) | ((st->rx[1] & 0xF0) >> 4); + len = sprintf(buf, "%d %c%c%c%c ", pos, + (status & 0x8) ? 'P' : 'V', + (status & 0x4) ? 'd' : '_', + (status & 0x2) ? 'l' : '_', + (status & 0x1) ? '1' : '0'); +error_ret: + /* delay (2 * AD2S120X_TSCLK + 20) ns for sample pulse */ + udelay(1); + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static ssize_t ad2s120x_show_vel(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct spi_message msg; + struct spi_transfer xfer; + int ret = 0; + ssize_t len = 0; + s16 vel; + u8 status; + struct iio_dev *idev = dev_get_drvdata(dev); + struct ad2s120x_state *st = idev->dev_data; + + xfer.len = 1; + xfer.tx_buf = st->tx; + xfer.rx_buf = st->rx; + mutex_lock(&st->lock); + + gpio_set_value(st->sample, 0); + /* delay (6 * AD2S120X_TSCLK + 20) nano seconds */ + udelay(1); + gpio_set_value(st->sample, 1); + + gpio_set_value(st->rdvel, 0); + /* ndelay(5);*/ + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + ret = spi_sync(st->sdev, &msg); + if (ret) + goto error_ret; + status = st->rx[1]; + vel = (st->rx[0] & 0x80) ? 0xf000 : 0; + vel |= (((s16)(st->rx[0])) << 4) | ((st->rx[1] & 0xF0) >> 4); + len += sprintf(buf + len, "%d %c%c%c%c\n", vel, + (status & 0x8) ? 'P' : 'V', + (status & 0x4) ? 'd' : '_', + (status & 0x2) ? 'l' : '_', + (status & 0x1) ? '1' : '0'); +error_ret: + gpio_set_value(st->rdvel, 1); + /* delay (2 * AD2S120X_TSCLK + 20) ns for sample pulse */ + udelay(1); + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static IIO_CONST_ATTR(description, + "12-Bit R/D Converter with Reference Oscillator"); +static IIO_DEVICE_ATTR(pos_vel, S_IRUGO, ad2s120x_show_pos_vel, NULL, 0); +static IIO_DEVICE_ATTR(pos, S_IRUGO, ad2s120x_show_pos, NULL, 0); +static IIO_DEVICE_ATTR(vel, S_IRUGO, ad2s120x_show_vel, NULL, 0); + +static struct attribute *ad2s120x_attributes[] = { + &iio_const_attr_description.dev_attr.attr, + &iio_dev_attr_pos_vel.dev_attr.attr, + &iio_dev_attr_pos.dev_attr.attr, + &iio_dev_attr_vel.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad2s120x_attribute_group = { + .name = DRV_NAME, + .attrs = ad2s120x_attributes, +}; + +static int __devinit ad2s120x_probe(struct spi_device *spi) +{ + struct ad2s120x_state *st; + int pn, ret = 0; + unsigned short *pins = spi->dev.platform_data; + + for (pn = 0; pn < AD2S120X_PN; pn++) { + if (gpio_request(pins[pn], DRV_NAME)) { + pr_err("%s: request gpio pin %d failed\n", + DRV_NAME, pins[pn]); + goto error_ret; + } + gpio_direction_output(pins[pn], 1); + } + + st = kzalloc(sizeof(*st), GFP_KERNEL); + if (st == NULL) { + ret = -ENOMEM; + goto error_ret; + } + spi_set_drvdata(spi, st); + + mutex_init(&st->lock); + st->sdev = spi; + st->sample = pins[0]; + st->rdvel = pins[1]; + + st->idev = iio_allocate_device(); + if (st->idev == NULL) { + ret = -ENOMEM; + goto error_free_st; + } + st->idev->dev.parent = &spi->dev; + st->idev->num_interrupt_lines = 0; + st->idev->event_attrs = NULL; + + st->idev->attrs = &ad2s120x_attribute_group; + st->idev->dev_data = (void *)(st); + st->idev->driver_module = THIS_MODULE; + st->idev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(st->idev); + if (ret) + goto error_free_dev; + + spi->max_speed_hz = AD2S120X_HZ; + spi->mode = SPI_MODE_3; + spi_setup(spi); + + return 0; + +error_free_dev: + iio_free_device(st->idev); +error_free_st: + kfree(st); +error_ret: + for (--pn; pn >= 0; pn--) + gpio_free(pins[pn]); + return ret; +} + +static int __devexit ad2s120x_remove(struct spi_device *spi) +{ + struct ad2s120x_state *st = spi_get_drvdata(spi); + + iio_device_unregister(st->idev); + kfree(st); + + return 0; +} + +static struct spi_driver ad2s120x_driver = { + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, + .probe = ad2s120x_probe, + .remove = __devexit_p(ad2s120x_remove), +}; + +static __init int ad2s120x_spi_init(void) +{ + return spi_register_driver(&ad2s120x_driver); +} +module_init(ad2s120x_spi_init); + +static __exit void ad2s120x_spi_exit(void) +{ + spi_unregister_driver(&ad2s120x_driver); +} +module_exit(ad2s120x_spi_exit); + +MODULE_AUTHOR("Graff Yang "); +MODULE_DESCRIPTION("Analog Devices AD2S1200/1205 Resolver to Digital SPI driver"); +MODULE_LICENSE("GPL v2"); -- 2.7.4