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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/iio/adc/men_z188_adc.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/iio/adc/men_z188_adc.c')
-rw-r--r--drivers/iio/adc/men_z188_adc.c179
1 files changed, 179 insertions, 0 deletions
diff --git a/drivers/iio/adc/men_z188_adc.c b/drivers/iio/adc/men_z188_adc.c
new file mode 100644
index 000000000..49827bb64
--- /dev/null
+++ b/drivers/iio/adc/men_z188_adc.c
@@ -0,0 +1,179 @@
+/*
+ * MEN 16z188 Analog to Digial Converter
+ *
+ * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
+ * Author: Johannes Thumshirn <johannes.thumshirn@men.de>
+ *
+ * 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; version 2 of the License.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mcb.h>
+#include <linux/io.h>
+#include <linux/iio/iio.h>
+
+#define Z188_ADC_MAX_CHAN 8
+#define Z188_ADC_GAIN 0x0700000
+#define Z188_MODE_VOLTAGE BIT(27)
+#define Z188_CFG_AUTO 0x1
+#define Z188_CTRL_REG 0x40
+
+#define ADC_DATA(x) (((x) >> 2) & 0x7ffffc)
+#define ADC_OVR(x) ((x) & 0x1)
+
+struct z188_adc {
+ struct resource *mem;
+ void __iomem *base;
+};
+
+#define Z188_ADC_CHANNEL(idx) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = (idx), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+}
+
+static const struct iio_chan_spec z188_adc_iio_channels[] = {
+ Z188_ADC_CHANNEL(0),
+ Z188_ADC_CHANNEL(1),
+ Z188_ADC_CHANNEL(2),
+ Z188_ADC_CHANNEL(3),
+ Z188_ADC_CHANNEL(4),
+ Z188_ADC_CHANNEL(5),
+ Z188_ADC_CHANNEL(6),
+ Z188_ADC_CHANNEL(7),
+};
+
+static int z188_iio_read_raw(struct iio_dev *iio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long info)
+{
+ struct z188_adc *adc = iio_priv(iio_dev);
+ int ret;
+ u16 tmp;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ tmp = readw(adc->base + chan->channel * 4);
+
+ if (ADC_OVR(tmp)) {
+ dev_info(&iio_dev->dev,
+ "Oversampling error on ADC channel %d\n",
+ chan->channel);
+ return -EIO;
+ }
+ *val = ADC_DATA(tmp);
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static const struct iio_info z188_adc_info = {
+ .read_raw = &z188_iio_read_raw,
+};
+
+static void men_z188_config_channels(void __iomem *addr)
+{
+ int i;
+ u32 cfg;
+ u32 ctl;
+
+ ctl = readl(addr + Z188_CTRL_REG);
+ ctl |= Z188_CFG_AUTO;
+ writel(ctl, addr + Z188_CTRL_REG);
+
+ for (i = 0; i < Z188_ADC_MAX_CHAN; i++) {
+ cfg = readl(addr + i);
+ cfg &= ~Z188_ADC_GAIN;
+ cfg |= Z188_MODE_VOLTAGE;
+ writel(cfg, addr + i);
+ }
+}
+
+static int men_z188_probe(struct mcb_device *dev,
+ const struct mcb_device_id *id)
+{
+ struct z188_adc *adc;
+ struct iio_dev *indio_dev;
+ struct resource *mem;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&dev->dev, sizeof(struct z188_adc));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ adc = iio_priv(indio_dev);
+ indio_dev->name = "z188-adc";
+ indio_dev->dev.parent = &dev->dev;
+ indio_dev->info = &z188_adc_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = z188_adc_iio_channels;
+ indio_dev->num_channels = ARRAY_SIZE(z188_adc_iio_channels);
+
+ mem = mcb_request_mem(dev, "z188-adc");
+ if (IS_ERR(mem))
+ return PTR_ERR(mem);
+
+ adc->base = ioremap(mem->start, resource_size(mem));
+ if (adc->base == NULL)
+ goto err;
+
+ men_z188_config_channels(adc->base);
+
+ adc->mem = mem;
+ mcb_set_drvdata(dev, indio_dev);
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto err_unmap;
+
+ return 0;
+
+err_unmap:
+ iounmap(adc->base);
+err:
+ mcb_release_mem(mem);
+ return -ENXIO;
+}
+
+static void men_z188_remove(struct mcb_device *dev)
+{
+ struct iio_dev *indio_dev = mcb_get_drvdata(dev);
+ struct z188_adc *adc = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ iounmap(adc->base);
+ mcb_release_mem(adc->mem);
+}
+
+static const struct mcb_device_id men_z188_ids[] = {
+ { .device = 0xbc },
+ { }
+};
+MODULE_DEVICE_TABLE(mcb, men_z188_ids);
+
+static struct mcb_driver men_z188_driver = {
+ .driver = {
+ .name = "z188-adc",
+ .owner = THIS_MODULE,
+ },
+ .probe = men_z188_probe,
+ .remove = men_z188_remove,
+ .id_table = men_z188_ids,
+};
+module_mcb_driver(men_z188_driver);
+
+MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("IIO ADC driver for MEN 16z188 ADC Core");
+MODULE_ALIAS("mcb:16z188");