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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-05 14:50:51 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-05 14:50:51 -0700
commit41844e36206be90cd4d962ea49b0abc3612a99d0 (patch)
treece0b3a3403bc6abdb28f52779d0d7b57a51a5c86 /drivers/iio/adc/stx104.c
parent5691f0e9a3e7855832d5fd094801bf600347c2d0 (diff)
parentfc1e2c8ea85e109acf09e74789e9b852f6eed251 (diff)
downloadop-kernel-dev-41844e36206be90cd4d962ea49b0abc3612a99d0.zip
op-kernel-dev-41844e36206be90cd4d962ea49b0abc3612a99d0.tar.gz
Merge tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO updates from Greg KH: "Here is the big staging and IIO driver pull request for 4.9-rc1. There are a lot of patches in here, the majority due to the drivers/staging/greybus/ subsystem being merged in with full development history that went back a few years, in order to preserve the work that those developers did over time. Lots and lots of tiny cleanups happened in the tree as well, due to the Outreachy application process and lots of other developers showing up for the first time to clean code up. Along with those changes, we deleted a wireless driver, and added a raspberrypi driver (currently marked broken), and lots of new iio drivers. Overall the tree still shrunk with more lines removed than added, about 10 thousand lines removed in total. Full details are in the very long shortlog below. All of this has been in the linux-next tree with no issues. There will be some merge problems with other subsystem trees, but those are all minor problems and shouldn't be hard to work out when they happen (MAINTAINERS and some lustre build problems with the IB tree)" And furter from me asking for clarification about greybus: "Right now there is a phone from Motorola shipping with this code (a slightly older version, but the same tree), so even though Ara is not alive in the same form, the functionality is happening. We are working with the developers of that phone to merge the newer stuff in with their fork so they can use the upstream version in future versions of their phone product line. Toshiba has at least one chip shipping in their catalog that needs/uses this protocol over a Unipro link, and rumor has it that there might be more in the future. There are also other users of the greybus protocols, there is a talk next week at ELC that shows how it is being used across a network connection to control a device, and previous ELC talks have showed the protocol stack being used over USB to drive embedded Linux boards. I've also talked to some people who are starting to work to add a host controller driver to control arduinos as the greybus PHY protocols are very useful to control a serial/i2c/spio/whatever device across a random physical link, as it is a way to have a self-describing device be attached to a host without needing manual configuration. So yes, people are using it, and there is still the chance that it will show up in a phone/laptop/tablet/whatever from Google in the future as well, the tech isn't dead, even if the original large phone project happens to be" * tag 'staging-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (3703 commits) Staging: fbtft: Fix bug in fbtft-core staging: rtl8188eu: fix double unlock error in rtw_resume_process() staging:r8188eu: remove GEN_MLME_EXT_HANDLER macro staging:r8188eu: remove GEN_DRV_CMD_HANDLER macro staging:r8188eu: remove GEN_EVT_CODE macro staging:r8188eu: remove GEN_CMD_CODE macro staging:r8188eu: remove pkt_newalloc member of the recv_buf structure staging:r8188eu: remove rtw_handle_dualmac declaration staging:r8188eu: remove (RGTRY|BSSID)_(OFT|SZ) macros staging:r8188eu: change rtl8188e_process_phy_info function argument type Staging: fsl-mc: Remove blank lines Staging: fsl-mc: Fix unaligned * in block comments Staging: comedi: Align the * in block comments Staging : ks7010 : Fix block comments warninig Staging: vt6655: Remove explicit NULL comparison using Coccinelle staging: rtl8188eu: core: rtw_xmit: Use macros instead of constants staging: rtl8188eu: core: rtw_xmit: Move constant of the right side staging: dgnc: Fix lines longer than 80 characters Staging: dgnc: constify attribute_group structures Staging: most: hdm-dim2: constify attribute_group structures ...
Diffstat (limited to 'drivers/iio/adc/stx104.c')
-rw-r--r--drivers/iio/adc/stx104.c380
1 files changed, 380 insertions, 0 deletions
diff --git a/drivers/iio/adc/stx104.c b/drivers/iio/adc/stx104.c
new file mode 100644
index 0000000..7e36457
--- /dev/null
+++ b/drivers/iio/adc/stx104.c
@@ -0,0 +1,380 @@
+/*
+ * IIO driver for the Apex Embedded Systems STX104
+ * Copyright (C) 2016 William Breathitt Gray
+ *
+ * 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.
+ */
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/gpio/driver.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/types.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/isa.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/spinlock.h>
+
+#define STX104_OUT_CHAN(chan) { \
+ .type = IIO_VOLTAGE, \
+ .channel = chan, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .indexed = 1, \
+ .output = 1 \
+}
+#define STX104_IN_CHAN(chan, diff) { \
+ .type = IIO_VOLTAGE, \
+ .channel = chan, \
+ .channel2 = chan, \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
+ BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .indexed = 1, \
+ .differential = diff \
+}
+
+#define STX104_NUM_OUT_CHAN 2
+
+#define STX104_EXTENT 16
+
+static unsigned int base[max_num_isa_dev(STX104_EXTENT)];
+static unsigned int num_stx104;
+module_param_array(base, uint, &num_stx104, 0);
+MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses");
+
+/**
+ * struct stx104_iio - IIO device private data structure
+ * @chan_out_states: channels' output states
+ * @base: base port address of the IIO device
+ */
+struct stx104_iio {
+ unsigned int chan_out_states[STX104_NUM_OUT_CHAN];
+ unsigned int base;
+};
+
+/**
+ * struct stx104_gpio - GPIO device private data structure
+ * @chip: instance of the gpio_chip
+ * @lock: synchronization lock to prevent I/O race conditions
+ * @base: base port address of the GPIO device
+ * @out_state: output bits state
+ */
+struct stx104_gpio {
+ struct gpio_chip chip;
+ spinlock_t lock;
+ unsigned int base;
+ unsigned int out_state;
+};
+
+/**
+ * struct stx104_dev - STX104 device private data structure
+ * @indio_dev: IIO device
+ * @chip: instance of the gpio_chip
+ */
+struct stx104_dev {
+ struct iio_dev *indio_dev;
+ struct gpio_chip *chip;
+};
+
+static int stx104_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val, int *val2, long mask)
+{
+ struct stx104_iio *const priv = iio_priv(indio_dev);
+ unsigned int adc_config;
+ int adbu;
+ int gain;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ /* get gain configuration */
+ adc_config = inb(priv->base + 11);
+ gain = adc_config & 0x3;
+
+ *val = 1 << gain;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_RAW:
+ if (chan->output) {
+ *val = priv->chan_out_states[chan->channel];
+ return IIO_VAL_INT;
+ }
+
+ /* select ADC channel */
+ outb(chan->channel | (chan->channel << 4), priv->base + 2);
+
+ /* trigger ADC sample capture and wait for completion */
+ outb(0, priv->base);
+ while (inb(priv->base + 8) & BIT(7));
+
+ *val = inw(priv->base);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_OFFSET:
+ /* get ADC bipolar/unipolar configuration */
+ adc_config = inb(priv->base + 11);
+ adbu = !(adc_config & BIT(2));
+
+ *val = -32768 * adbu;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ /* get ADC bipolar/unipolar and gain configuration */
+ adc_config = inb(priv->base + 11);
+ adbu = !(adc_config & BIT(2));
+ gain = adc_config & 0x3;
+
+ *val = 5;
+ *val2 = 15 - adbu + gain;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ }
+
+ return -EINVAL;
+}
+
+static int stx104_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val, int val2, long mask)
+{
+ struct stx104_iio *const priv = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ /* Only four gain states (x1, x2, x4, x8) */
+ switch (val) {
+ case 1:
+ outb(0, priv->base + 11);
+ break;
+ case 2:
+ outb(1, priv->base + 11);
+ break;
+ case 4:
+ outb(2, priv->base + 11);
+ break;
+ case 8:
+ outb(3, priv->base + 11);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+ case IIO_CHAN_INFO_RAW:
+ if (chan->output) {
+ /* DAC can only accept up to a 16-bit value */
+ if ((unsigned int)val > 65535)
+ return -EINVAL;
+
+ priv->chan_out_states[chan->channel] = val;
+ outw(val, priv->base + 4 + 2 * chan->channel);
+
+ return 0;
+ }
+ return -EINVAL;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info stx104_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = stx104_read_raw,
+ .write_raw = stx104_write_raw
+};
+
+/* single-ended input channels configuration */
+static const struct iio_chan_spec stx104_channels_sing[] = {
+ STX104_OUT_CHAN(0), STX104_OUT_CHAN(1),
+ STX104_IN_CHAN(0, 0), STX104_IN_CHAN(1, 0), STX104_IN_CHAN(2, 0),
+ STX104_IN_CHAN(3, 0), STX104_IN_CHAN(4, 0), STX104_IN_CHAN(5, 0),
+ STX104_IN_CHAN(6, 0), STX104_IN_CHAN(7, 0), STX104_IN_CHAN(8, 0),
+ STX104_IN_CHAN(9, 0), STX104_IN_CHAN(10, 0), STX104_IN_CHAN(11, 0),
+ STX104_IN_CHAN(12, 0), STX104_IN_CHAN(13, 0), STX104_IN_CHAN(14, 0),
+ STX104_IN_CHAN(15, 0)
+};
+/* differential input channels configuration */
+static const struct iio_chan_spec stx104_channels_diff[] = {
+ STX104_OUT_CHAN(0), STX104_OUT_CHAN(1),
+ STX104_IN_CHAN(0, 1), STX104_IN_CHAN(1, 1), STX104_IN_CHAN(2, 1),
+ STX104_IN_CHAN(3, 1), STX104_IN_CHAN(4, 1), STX104_IN_CHAN(5, 1),
+ STX104_IN_CHAN(6, 1), STX104_IN_CHAN(7, 1)
+};
+
+static int stx104_gpio_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ /* GPIO 0-3 are input only, while the rest are output only */
+ if (offset < 4)
+ return 1;
+
+ return 0;
+}
+
+static int stx104_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ if (offset >= 4)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int stx104_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ if (offset < 4)
+ return -EINVAL;
+
+ chip->set(chip, offset, value);
+ return 0;
+}
+
+static int stx104_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct stx104_gpio *const stx104gpio = gpiochip_get_data(chip);
+
+ if (offset >= 4)
+ return -EINVAL;
+
+ return !!(inb(stx104gpio->base) & BIT(offset));
+}
+
+static void stx104_gpio_set(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct stx104_gpio *const stx104gpio = gpiochip_get_data(chip);
+ const unsigned int mask = BIT(offset) >> 4;
+ unsigned long flags;
+
+ if (offset < 4)
+ return;
+
+ spin_lock_irqsave(&stx104gpio->lock, flags);
+
+ if (value)
+ stx104gpio->out_state |= mask;
+ else
+ stx104gpio->out_state &= ~mask;
+
+ outb(stx104gpio->out_state, stx104gpio->base);
+
+ spin_unlock_irqrestore(&stx104gpio->lock, flags);
+}
+
+static int stx104_probe(struct device *dev, unsigned int id)
+{
+ struct iio_dev *indio_dev;
+ struct stx104_iio *priv;
+ struct stx104_gpio *stx104gpio;
+ struct stx104_dev *stx104dev;
+ int err;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ stx104gpio = devm_kzalloc(dev, sizeof(*stx104gpio), GFP_KERNEL);
+ if (!stx104gpio)
+ return -ENOMEM;
+
+ stx104dev = devm_kzalloc(dev, sizeof(*stx104dev), GFP_KERNEL);
+ if (!stx104dev)
+ return -ENOMEM;
+
+ if (!devm_request_region(dev, base[id], STX104_EXTENT,
+ dev_name(dev))) {
+ dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
+ base[id], base[id] + STX104_EXTENT);
+ return -EBUSY;
+ }
+
+ indio_dev->info = &stx104_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ /* determine if differential inputs */
+ if (inb(base[id] + 8) & BIT(5)) {
+ indio_dev->num_channels = ARRAY_SIZE(stx104_channels_diff);
+ indio_dev->channels = stx104_channels_diff;
+ } else {
+ indio_dev->num_channels = ARRAY_SIZE(stx104_channels_sing);
+ indio_dev->channels = stx104_channels_sing;
+ }
+
+ indio_dev->name = dev_name(dev);
+
+ priv = iio_priv(indio_dev);
+ priv->base = base[id];
+
+ /* configure device for software trigger operation */
+ outb(0, base[id] + 9);
+
+ /* initialize gain setting to x1 */
+ outb(0, base[id] + 11);
+
+ /* initialize DAC output to 0V */
+ outw(0, base[id] + 4);
+ outw(0, base[id] + 6);
+
+ stx104gpio->chip.label = dev_name(dev);
+ stx104gpio->chip.parent = dev;
+ stx104gpio->chip.owner = THIS_MODULE;
+ stx104gpio->chip.base = -1;
+ stx104gpio->chip.ngpio = 8;
+ stx104gpio->chip.get_direction = stx104_gpio_get_direction;
+ stx104gpio->chip.direction_input = stx104_gpio_direction_input;
+ stx104gpio->chip.direction_output = stx104_gpio_direction_output;
+ stx104gpio->chip.get = stx104_gpio_get;
+ stx104gpio->chip.set = stx104_gpio_set;
+ stx104gpio->base = base[id] + 3;
+ stx104gpio->out_state = 0x0;
+
+ spin_lock_init(&stx104gpio->lock);
+
+ stx104dev->indio_dev = indio_dev;
+ stx104dev->chip = &stx104gpio->chip;
+ dev_set_drvdata(dev, stx104dev);
+
+ err = gpiochip_add_data(&stx104gpio->chip, stx104gpio);
+ if (err) {
+ dev_err(dev, "GPIO registering failed (%d)\n", err);
+ return err;
+ }
+
+ err = iio_device_register(indio_dev);
+ if (err) {
+ dev_err(dev, "IIO device registering failed (%d)\n", err);
+ gpiochip_remove(&stx104gpio->chip);
+ return err;
+ }
+
+ return 0;
+}
+
+static int stx104_remove(struct device *dev, unsigned int id)
+{
+ struct stx104_dev *const stx104dev = dev_get_drvdata(dev);
+
+ iio_device_unregister(stx104dev->indio_dev);
+ gpiochip_remove(stx104dev->chip);
+
+ return 0;
+}
+
+static struct isa_driver stx104_driver = {
+ .probe = stx104_probe,
+ .driver = {
+ .name = "stx104"
+ },
+ .remove = stx104_remove
+};
+
+module_isa_driver(stx104_driver, num_stx104);
+
+MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
+MODULE_DESCRIPTION("Apex Embedded Systems STX104 IIO driver");
+MODULE_LICENSE("GPL v2");
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