diff options
Diffstat (limited to 'drivers/iio/adc/adi-axi-adc.c')
| -rw-r--r-- | drivers/iio/adc/adi-axi-adc.c | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c new file mode 100644 index 000000000..d721fb1bc --- /dev/null +++ b/drivers/iio/adc/adi-axi-adc.c @@ -0,0 +1,440 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices Generic AXI ADC IP core + * Link: https://wiki.analog.com/resources/fpga/docs/axi_adc_ip + * + * Copyright 2012-2020 Analog Devices Inc. + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/buffer.h> +#include <linux/iio/buffer-dmaengine.h> + +#include <linux/fpga/adi-axi-common.h> +#include <linux/iio/adc/adi-axi-adc.h> + +/** + * Register definitions: + * https://wiki.analog.com/resources/fpga/docs/axi_adc_ip#register_map + */ + +/* ADC controls */ + +#define ADI_AXI_REG_RSTN 0x0040 +#define ADI_AXI_REG_RSTN_CE_N BIT(2) +#define ADI_AXI_REG_RSTN_MMCM_RSTN BIT(1) +#define ADI_AXI_REG_RSTN_RSTN BIT(0) + +/* ADC Channel controls */ + +#define ADI_AXI_REG_CHAN_CTRL(c) (0x0400 + (c) * 0x40) +#define ADI_AXI_REG_CHAN_CTRL_LB_OWR BIT(11) +#define ADI_AXI_REG_CHAN_CTRL_PN_SEL_OWR BIT(10) +#define ADI_AXI_REG_CHAN_CTRL_IQCOR_EN BIT(9) +#define ADI_AXI_REG_CHAN_CTRL_DCFILT_EN BIT(8) +#define ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT BIT(6) +#define ADI_AXI_REG_CHAN_CTRL_FMT_TYPE BIT(5) +#define ADI_AXI_REG_CHAN_CTRL_FMT_EN BIT(4) +#define ADI_AXI_REG_CHAN_CTRL_PN_TYPE_OWR BIT(1) +#define ADI_AXI_REG_CHAN_CTRL_ENABLE BIT(0) + +#define ADI_AXI_REG_CHAN_CTRL_DEFAULTS \ + (ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT | \ + ADI_AXI_REG_CHAN_CTRL_FMT_EN | \ + ADI_AXI_REG_CHAN_CTRL_ENABLE) + +struct adi_axi_adc_core_info { + unsigned int version; +}; + +struct adi_axi_adc_state { + struct mutex lock; + + struct adi_axi_adc_client *client; + void __iomem *regs; +}; + +struct adi_axi_adc_client { + struct list_head entry; + struct adi_axi_adc_conv conv; + struct adi_axi_adc_state *state; + struct device *dev; + const struct adi_axi_adc_core_info *info; +}; + +static LIST_HEAD(registered_clients); +static DEFINE_MUTEX(registered_clients_lock); + +static struct adi_axi_adc_client *conv_to_client(struct adi_axi_adc_conv *conv) +{ + return container_of(conv, struct adi_axi_adc_client, conv); +} + +void *adi_axi_adc_conv_priv(struct adi_axi_adc_conv *conv) +{ + struct adi_axi_adc_client *cl = conv_to_client(conv); + + return (char *)cl + ALIGN(sizeof(struct adi_axi_adc_client), IIO_ALIGN); +} +EXPORT_SYMBOL_GPL(adi_axi_adc_conv_priv); + +static void adi_axi_adc_write(struct adi_axi_adc_state *st, + unsigned int reg, + unsigned int val) +{ + iowrite32(val, st->regs + reg); +} + +static unsigned int adi_axi_adc_read(struct adi_axi_adc_state *st, + unsigned int reg) +{ + return ioread32(st->regs + reg); +} + +static int adi_axi_adc_config_dma_buffer(struct device *dev, + struct iio_dev *indio_dev) +{ + struct iio_buffer *buffer; + const char *dma_name; + + if (!device_property_present(dev, "dmas")) + return 0; + + if (device_property_read_string(dev, "dma-names", &dma_name)) + dma_name = "rx"; + + buffer = devm_iio_dmaengine_buffer_alloc(indio_dev->dev.parent, + dma_name); + if (IS_ERR(buffer)) + return PTR_ERR(buffer); + + indio_dev->modes |= INDIO_BUFFER_HARDWARE; + iio_device_attach_buffer(indio_dev, buffer); + + return 0; +} + +static int adi_axi_adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct adi_axi_adc_state *st = iio_priv(indio_dev); + struct adi_axi_adc_conv *conv = &st->client->conv; + + if (!conv->read_raw) + return -EOPNOTSUPP; + + return conv->read_raw(conv, chan, val, val2, mask); +} + +static int adi_axi_adc_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct adi_axi_adc_state *st = iio_priv(indio_dev); + struct adi_axi_adc_conv *conv = &st->client->conv; + + if (!conv->write_raw) + return -EOPNOTSUPP; + + return conv->write_raw(conv, chan, val, val2, mask); +} + +static int adi_axi_adc_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + struct adi_axi_adc_state *st = iio_priv(indio_dev); + struct adi_axi_adc_conv *conv = &st->client->conv; + + if (!conv->read_avail) + return -EOPNOTSUPP; + + return conv->read_avail(conv, chan, vals, type, length, mask); +} + +static int adi_axi_adc_update_scan_mode(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct adi_axi_adc_state *st = iio_priv(indio_dev); + struct adi_axi_adc_conv *conv = &st->client->conv; + unsigned int i, ctrl; + + for (i = 0; i < conv->chip_info->num_channels; i++) { + ctrl = adi_axi_adc_read(st, ADI_AXI_REG_CHAN_CTRL(i)); + + if (test_bit(i, scan_mask)) + ctrl |= ADI_AXI_REG_CHAN_CTRL_ENABLE; + else + ctrl &= ~ADI_AXI_REG_CHAN_CTRL_ENABLE; + + adi_axi_adc_write(st, ADI_AXI_REG_CHAN_CTRL(i), ctrl); + } + + return 0; +} + +static struct adi_axi_adc_conv *adi_axi_adc_conv_register(struct device *dev, + size_t sizeof_priv) +{ + struct adi_axi_adc_client *cl; + size_t alloc_size; + + alloc_size = ALIGN(sizeof(struct adi_axi_adc_client), IIO_ALIGN); + if (sizeof_priv) + alloc_size += ALIGN(sizeof_priv, IIO_ALIGN); + + cl = kzalloc(alloc_size, GFP_KERNEL); + if (!cl) + return ERR_PTR(-ENOMEM); + + mutex_lock(®istered_clients_lock); + + cl->dev = get_device(dev); + + list_add_tail(&cl->entry, ®istered_clients); + + mutex_unlock(®istered_clients_lock); + + return &cl->conv; +} + +static void adi_axi_adc_conv_unregister(struct adi_axi_adc_conv *conv) +{ + struct adi_axi_adc_client *cl = conv_to_client(conv); + + mutex_lock(®istered_clients_lock); + + list_del(&cl->entry); + put_device(cl->dev); + + mutex_unlock(®istered_clients_lock); + + kfree(cl); +} + +static void devm_adi_axi_adc_conv_release(struct device *dev, void *res) +{ + adi_axi_adc_conv_unregister(*(struct adi_axi_adc_conv **)res); +} + +struct adi_axi_adc_conv *devm_adi_axi_adc_conv_register(struct device *dev, + size_t sizeof_priv) +{ + struct adi_axi_adc_conv **ptr, *conv; + + ptr = devres_alloc(devm_adi_axi_adc_conv_release, sizeof(*ptr), + GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + conv = adi_axi_adc_conv_register(dev, sizeof_priv); + if (IS_ERR(conv)) { + devres_free(ptr); + return ERR_CAST(conv); + } + + *ptr = conv; + devres_add(dev, ptr); + + return conv; +} +EXPORT_SYMBOL_GPL(devm_adi_axi_adc_conv_register); + +static const struct iio_info adi_axi_adc_info = { + .read_raw = &adi_axi_adc_read_raw, + .write_raw = &adi_axi_adc_write_raw, + .update_scan_mode = &adi_axi_adc_update_scan_mode, + .read_avail = &adi_axi_adc_read_avail, +}; + +static const struct adi_axi_adc_core_info adi_axi_adc_10_0_a_info = { + .version = ADI_AXI_PCORE_VER(10, 0, 'a'), +}; + +static struct adi_axi_adc_client *adi_axi_adc_attach_client(struct device *dev) +{ + const struct adi_axi_adc_core_info *info; + struct adi_axi_adc_client *cl; + struct device_node *cln; + + info = of_device_get_match_data(dev); + if (!info) + return ERR_PTR(-ENODEV); + + cln = of_parse_phandle(dev->of_node, "adi,adc-dev", 0); + if (!cln) { + dev_err(dev, "No 'adi,adc-dev' node defined\n"); + return ERR_PTR(-ENODEV); + } + + mutex_lock(®istered_clients_lock); + + list_for_each_entry(cl, ®istered_clients, entry) { + if (!cl->dev) + continue; + + if (cl->dev->of_node != cln) + continue; + + if (!try_module_get(cl->dev->driver->owner)) { + mutex_unlock(®istered_clients_lock); + of_node_put(cln); + return ERR_PTR(-ENODEV); + } + + get_device(cl->dev); + cl->info = info; + mutex_unlock(®istered_clients_lock); + of_node_put(cln); + return cl; + } + + mutex_unlock(®istered_clients_lock); + of_node_put(cln); + + return ERR_PTR(-EPROBE_DEFER); +} + +static int adi_axi_adc_setup_channels(struct device *dev, + struct adi_axi_adc_state *st) +{ + struct adi_axi_adc_conv *conv = &st->client->conv; + int i, ret; + + if (conv->preenable_setup) { + ret = conv->preenable_setup(conv); + if (ret) + return ret; + } + + for (i = 0; i < conv->chip_info->num_channels; i++) { + adi_axi_adc_write(st, ADI_AXI_REG_CHAN_CTRL(i), + ADI_AXI_REG_CHAN_CTRL_DEFAULTS); + } + + return 0; +} + +static void axi_adc_reset(struct adi_axi_adc_state *st) +{ + adi_axi_adc_write(st, ADI_AXI_REG_RSTN, 0); + mdelay(10); + adi_axi_adc_write(st, ADI_AXI_REG_RSTN, ADI_AXI_REG_RSTN_MMCM_RSTN); + mdelay(10); + adi_axi_adc_write(st, ADI_AXI_REG_RSTN, + ADI_AXI_REG_RSTN_RSTN | ADI_AXI_REG_RSTN_MMCM_RSTN); +} + +static void adi_axi_adc_cleanup(void *data) +{ + struct adi_axi_adc_client *cl = data; + + put_device(cl->dev); + module_put(cl->dev->driver->owner); +} + +static int adi_axi_adc_probe(struct platform_device *pdev) +{ + struct adi_axi_adc_conv *conv; + struct iio_dev *indio_dev; + struct adi_axi_adc_client *cl; + struct adi_axi_adc_state *st; + unsigned int ver; + int ret; + + cl = adi_axi_adc_attach_client(&pdev->dev); + if (IS_ERR(cl)) + return PTR_ERR(cl); + + ret = devm_add_action_or_reset(&pdev->dev, adi_axi_adc_cleanup, cl); + if (ret) + return ret; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st)); + if (indio_dev == NULL) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->client = cl; + cl->state = st; + mutex_init(&st->lock); + + st->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(st->regs)) + return PTR_ERR(st->regs); + + conv = &st->client->conv; + + axi_adc_reset(st); + + ver = adi_axi_adc_read(st, ADI_AXI_REG_VERSION); + + if (cl->info->version > ver) { + dev_err(&pdev->dev, + "IP core version is too old. Expected %d.%.2d.%c, Reported %d.%.2d.%c\n", + ADI_AXI_PCORE_VER_MAJOR(cl->info->version), + ADI_AXI_PCORE_VER_MINOR(cl->info->version), + ADI_AXI_PCORE_VER_PATCH(cl->info->version), + ADI_AXI_PCORE_VER_MAJOR(ver), + ADI_AXI_PCORE_VER_MINOR(ver), + ADI_AXI_PCORE_VER_PATCH(ver)); + return -ENODEV; + } + + indio_dev->info = &adi_axi_adc_info; + indio_dev->name = "adi-axi-adc"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->num_channels = conv->chip_info->num_channels; + indio_dev->channels = conv->chip_info->channels; + + ret = adi_axi_adc_config_dma_buffer(&pdev->dev, indio_dev); + if (ret) + return ret; + + ret = adi_axi_adc_setup_channels(&pdev->dev, st); + if (ret) + return ret; + + ret = devm_iio_device_register(&pdev->dev, indio_dev); + if (ret) + return ret; + + dev_info(&pdev->dev, "AXI ADC IP core (%d.%.2d.%c) probed\n", + ADI_AXI_PCORE_VER_MAJOR(ver), + ADI_AXI_PCORE_VER_MINOR(ver), + ADI_AXI_PCORE_VER_PATCH(ver)); + + return 0; +} + +/* Match table for of_platform binding */ +static const struct of_device_id adi_axi_adc_of_match[] = { + { .compatible = "adi,axi-adc-10.0.a", .data = &adi_axi_adc_10_0_a_info }, + { /* end of list */ } +}; +MODULE_DEVICE_TABLE(of, adi_axi_adc_of_match); + +static struct platform_driver adi_axi_adc_driver = { + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = adi_axi_adc_of_match, + }, + .probe = adi_axi_adc_probe, +}; +module_platform_driver(adi_axi_adc_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); +MODULE_DESCRIPTION("Analog Devices Generic AXI ADC IP core driver"); +MODULE_LICENSE("GPL v2"); |