// SPDX-License-Identifier: GPL-2.0
/*
* Turris Mox module configuration bus driver
*
* Copyright (C) 2019 Marek Behún <[email protected]>
*/
#include <dt-bindings/bus/moxtet.h>
#include <linux/bitops.h>
#include <linux/debugfs.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/moxtet.h>
#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/spi/spi.h>
/*
* @name: module name for sysfs
* @hwirq_base: base index for IRQ for this module (-1 if no IRQs)
* @nirqs: how many interrupts does the shift register provide
* @desc: module description for kernel log
*/
static const struct {
const char *name;
int hwirq_base;
int nirqs;
const char *desc;
} mox_module_table[] = {
/* do not change order of this array! */
{ NULL, 0, 0, NULL },
{ "sfp", -1, 0, "MOX D (SFP cage)" },
{ "pci", MOXTET_IRQ_PCI, 1, "MOX B (Mini-PCIe)" },
{ "topaz", MOXTET_IRQ_TOPAZ, 1, "MOX C (4 port switch)" },
{ "peridot", MOXTET_IRQ_PERIDOT(0), 1, "MOX E (8 port switch)" },
{ "usb3", MOXTET_IRQ_USB3, 2, "MOX F (USB 3.0)" },
{ "pci-bridge", -1, 0, "MOX G (Mini-PCIe bridge)" },
};
static inline bool mox_module_known(unsigned int id)
{
return id >= TURRIS_MOX_MODULE_FIRST && id <= TURRIS_MOX_MODULE_LAST;
}
static inline const char *mox_module_name(unsigned int id)
{
if (mox_module_known(id))
return mox_module_table[id].name;
else
return "unknown";
}
#define DEF_MODULE_ATTR(name, fmt, ...) \
static ssize_t \
module_##name##_show(struct device *dev, struct device_attribute *a, \
char *buf) \
{ \
struct moxtet_device *mdev = to_moxtet_device(dev); \
return sprintf(buf, (fmt), __VA_ARGS__); \
} \
static DEVICE_ATTR_RO(module_##name)
DEF_MODULE_ATTR(id, "0x%x\n", mdev->id);
DEF_MODULE_ATTR(name, "%s\n", mox_module_name(mdev->id));
DEF_MODULE_ATTR(description, "%s\n",
mox_module_known(mdev->id) ? mox_module_table[mdev->id].desc
: "");
static struct attribute *moxtet_dev_attrs[] = {
&dev_attr_module_id.attr,
&dev_attr_module_name.attr,
&dev_attr_module_description.attr,
NULL,
};
static const struct attribute_group moxtet_dev_group = {
.attrs = moxtet_dev_attrs,
};
static const struct attribute_group *moxtet_dev_groups[] = {
&moxtet_dev_group,
NULL,
};
static int moxtet_match(struct device *dev, const struct device_driver *drv)
{
struct moxtet_device *mdev = to_moxtet_device(dev);
const struct moxtet_driver *tdrv = to_moxtet_driver(drv);
const enum turris_mox_module_id *t;
if (of_driver_match_device(dev, drv))
return 1;
if (!tdrv->id_table)
return 0;
for (t = tdrv->id_table; *t; ++t)
if (*t == mdev->id)
return 1;
return 0;
}
static const struct bus_type moxtet_bus_type = {
.name = "moxtet",
.dev_groups = moxtet_dev_groups,
.match = moxtet_match,
};
int __moxtet_register_driver(struct module *owner,
struct moxtet_driver *mdrv)
{
mdrv->driver.owner = owner;
mdrv->driver.bus = &moxtet_bus_type;
return driver_register(&mdrv->driver);
}
EXPORT_SYMBOL_GPL(__moxtet_register_driver);
static int moxtet_dev_check(struct device *dev, void *data)
{
struct moxtet_device *mdev = to_moxtet_device(dev);
struct moxtet_device *new_dev = data;
if (mdev->moxtet == new_dev->moxtet && mdev->id == new_dev->id &&
mdev->idx == new_dev->idx)
return -EBUSY;
return 0;
}
static void moxtet_dev_release(struct device *dev)
{
struct moxtet_device *mdev = to_moxtet_device(dev);
put_device(mdev->moxtet->dev);
kfree(mdev);
}
static struct moxtet_device *
moxtet_alloc_device(struct moxtet *moxtet)
{
struct moxtet_device *dev;
if (!get_device(moxtet->dev))
return NULL;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev) {
put_device(moxtet->dev);
return NULL;
}
dev->moxtet = moxtet;
dev->dev.parent = moxtet->dev;
dev->dev.bus = &moxtet_bus_type;
dev->dev.release = moxtet_dev_release;
device_initialize(&dev->dev);
return dev;
}
static int moxtet_add_device(struct moxtet_device *dev)
{
static DEFINE_MUTEX(add_mutex);
int ret;
if (dev->idx >= TURRIS_MOX_MAX_MODULES || dev->id > 0xf)
return -EINVAL;
dev_set_name(&dev->dev, "moxtet-%s.%u", mox_module_name(dev->id),
dev->idx);
mutex_lock(&add_mutex);
ret = bus_for_each_dev(&moxtet_bus_type, NULL, dev,
moxtet_dev_check);
if (ret)
goto done;
ret = device_add(&dev->dev);
if (ret < 0)
dev_err(dev->moxtet->dev, "can't add %s, status %d\n",
dev_name(dev->moxtet->dev), ret);
done:
mutex_unlock(&add_mutex);
return ret;
}
static int __unregister(struct device *dev, void *null)
{
if (dev->of_node) {
of_node_clear_flag(dev->of_node, OF_POPULATED);
of_node_put(dev->of_node);
}
device_unregister(dev);
return 0;
}
static struct moxtet_device *
of_register_moxtet_device(struct moxtet *moxtet, struct device_node *nc)
{
struct moxtet_device *dev;
u32 val;
int ret;
dev = moxtet_alloc_device(moxtet);
if (!dev) {
dev_err(moxtet->dev,
"Moxtet device alloc error for %pOF\n", nc);
return ERR_PTR(-ENOMEM);
}
ret = of_property_read_u32(nc, "reg", &val);
if (ret) {
dev_err(moxtet->dev, "%pOF has no valid 'reg' property (%d)\n",
nc, ret);
goto err_put;
}
dev->idx = val;
if (dev->idx >= TURRIS_MOX_MAX_MODULES) {
dev_err(moxtet->dev, "%pOF Moxtet address 0x%x out of range\n",
nc, dev->idx);
ret = -EINVAL;
goto err_put;
}
dev->id = moxtet->modules[dev->idx];
if (!dev->id) {
dev_err(moxtet->dev, "%pOF Moxtet address 0x%x is empty\n", nc,
dev->idx);
ret = -ENODEV;
goto err_put;
}
of_node_get(nc);
dev->dev.of_node = nc;
ret = moxtet_add_device(dev);
if (ret) {
dev_err(moxtet->dev,
"Moxtet device register error for %pOF\n", nc);
of_node_put(nc);
goto err_put;
}
return dev;
err_put:
put_device(&dev->dev);
return ERR_PTR(ret);
}
static void of_register_moxtet_devices(struct moxtet *moxtet)
{
struct moxtet_device *dev;
struct device_node *nc;
if (!moxtet->dev->of_node)
return;
for_each_available_child_of_node(moxtet->dev->of_node, nc) {
if (of_node_test_and_set_flag(nc, OF_POPULATED))
continue;
dev = of_register_moxtet_device(moxtet, nc);
if (IS_ERR(dev)) {
dev_warn(moxtet->dev,
"Failed to create Moxtet device for %pOF\n",
nc);
of_node_clear_flag(nc, OF_POPULATED);
}
}
}
static void
moxtet_register_devices_from_topology(struct moxtet *moxtet)
{
struct moxtet_device *dev;
int i, ret;
for (i = 0; i < moxtet->count; ++i) {
dev = moxtet_alloc_device(moxtet);
if (!dev) {
dev_err(moxtet->dev, "Moxtet device %u alloc error\n",
i);
continue;
}
dev->idx = i;
dev->id = moxtet->modules[i];
ret = moxtet_add_device(dev);
if (ret && ret != -EBUSY) {
put_device(&dev->dev);
dev_err(moxtet->dev,
"Moxtet device %u register error: %i\n", i,
ret);
}
}
}
/*
* @nsame: how many modules with same id are already in moxtet->modules
*/
static int moxtet_set_irq(struct moxtet *moxtet, int idx, int id, int nsame)
{
int i, first;
struct moxtet_irqpos *pos;
first = mox_module_table[id].hwirq_base +
nsame * mox_module_table[id].nirqs;
if (first + mox_module_table[id].nirqs > MOXTET_NIRQS)
return -EINVAL;
for (i = 0; i < mox_module_table[id].nirqs; ++i) {
pos = &moxtet->irq.position[first + i];
pos->idx = idx;
pos->bit = i;
moxtet->irq.exists |= BIT(first + i);
}
return 0;
}
static int moxtet_find_topology(struct moxtet *moxtet)
{
u8 buf[TURRIS_MOX_MAX_MODULES];
int cnts[TURRIS_MOX_MODULE_LAST];
int i, ret;
memset(cnts, 0, sizeof(cnts));
ret = spi_read(to_spi_device(moxtet->dev), buf, TURRIS_MOX_MAX_MODULES);
if (ret < 0)
return ret;
if (buf[0] == TURRIS_MOX_CPU_ID_EMMC) {
dev_info(moxtet->dev, "Found MOX A (eMMC CPU) module\n");
} else if (buf[0] == TURRIS_MOX_CPU_ID_SD) {
dev_info(moxtet->dev, "Found MOX A (CPU) module\n");
} else {
dev_err(moxtet->dev, "Invalid Turris MOX A CPU module 0x%02x\n",
buf[0]);
return -ENODEV;
}
moxtet->count = 0;
for (i = 1; i < TURRIS_MOX_MAX_MODULES; ++i) {
int id;
if (buf[i] == 0xff)
break;
id = buf[i] & 0xf;
moxtet->modules[i-1] = id;
++moxtet->count;
if (mox_module_known(id)) {
dev_info(moxtet->dev, "Found %s module\n",
mox_module_table[id].desc);
if (moxtet_set_irq(moxtet, i-1, id, cnts[id]++) < 0)
dev_err(moxtet->dev,
" Cannot set IRQ for module %s\n",
mox_module_table[id].desc);
} else {
dev_warn(moxtet->dev,
"Unknown Moxtet module found (ID 0x%02x)\n",
id);
}
}
return 0;
}
static int moxtet_spi_read(struct moxtet *moxtet, u8 *buf)
{
struct spi_transfer xfer = {
.rx_buf = buf,
.tx_buf = moxtet->tx,
.len = moxtet->count + 1
};
int ret;
mutex_lock(&moxtet->lock);
ret = spi_sync_transfer(to_spi_device(moxtet->dev), &xfer, 1);
mutex_unlock(&moxtet->lock);
return ret;
}
int moxtet_device_read(struct device *dev)
{
struct moxtet_device *mdev = to_moxtet_device(dev);
struct moxtet *moxtet = mdev->moxtet;
u8 buf[TURRIS_MOX_MAX_MODULES];
int ret;
if (mdev->idx >= moxtet->count)
return -EINVAL;
ret = moxtet_spi_read(moxtet, buf);
if (ret < 0)
return ret;
return buf[mdev->idx + 1] >> 4;
}
EXPORT_SYMBOL_GPL(moxtet_device_read);
int moxtet_device_write(struct device *dev, u8 val)
{
struct moxtet_device *mdev = to_moxtet_device(dev);
struct moxtet *moxtet = mdev->moxtet;
int ret;
if (mdev->idx >= moxtet->count)
return -EINVAL;
mutex_lock(&moxtet->lock);
moxtet->tx[moxtet->count - mdev->idx] = val;
ret = spi_write(to_spi_device(moxtet->dev), moxtet->tx,
moxtet->count + 1);
mutex_unlock(&moxtet->lock);
return ret;
}
EXPORT_SYMBOL_GPL(moxtet_device_write);
int moxtet_device_written(struct device *dev)
{
struct moxtet_device *mdev = to_moxtet_device(dev);
struct moxtet *moxtet = mdev->moxtet;
if (mdev->idx >= moxtet->count)
return -EINVAL;
return moxtet->tx[moxtet->count - mdev->idx];
}
EXPORT_SYMBOL_GPL(moxtet_device_written);
#ifdef CONFIG_DEBUG_FS
static int moxtet_debug_open(struct inode *inode, struct file *file)
{
file->private_data = inode->i_private;
return nonseekable_open(inode, file);
}
static ssize_t input_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
struct moxtet *moxtet = file->private_data;
u8 bin[TURRIS_MOX_MAX_MODULES];
u8 hex[sizeof(bin) * 2 + 1];
int ret, n;
ret = moxtet_spi_read(moxtet, bin);
if (ret < 0)
return ret;
n = moxtet->count + 1;
bin2hex(hex, bin, n);
hex[2*n] = '\n';
return simple_read_from_buffer(buf, len, ppos, hex, 2*n + 1);
}
static const struct file_operations input_fops = {
.owner = THIS_MODULE,
.open = moxtet_debug_open,
.read = input_read,
};
static ssize_t output_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
struct moxtet *moxtet = file->private_data;
u8 hex[TURRIS_MOX_MAX_MODULES * 2 + 1];
u8 *p = hex;
int i;
mutex_lock(&moxtet->lock);
for (i = 0; i < moxtet->count; ++i)
p = hex_byte_pack(p, moxtet->tx[moxtet->count - i]);
mutex_unlock(&moxtet->lock);
*p++ = '\n';
return simple_read_from_buffer(buf, len, ppos, hex, p - hex);
}
static ssize_t output_write(struct file *file, const char __user *buf,
size_t len, loff_t *ppos)
{
struct moxtet *moxtet = file->private_data;
u8 bin[TURRIS_MOX_MAX_MODULES];
u8 hex[sizeof(bin) * 2 + 1];
ssize_t res;
loff_t dummy = 0;
int err, i;
if (len > 2 * moxtet->count + 1 || len < 2 * moxtet->count)
return -EINVAL;
res = simple_write_to_buffer(hex, sizeof(hex), &dummy, buf, len);
if (res < 0)
return res;
if (len % 2 == 1 && hex[len - 1] != '\n')
return -EINVAL;
err = hex2bin(bin, hex, moxtet->count);
if (err < 0)
return -EINVAL;
mutex_lock(&moxtet->lock);
for (i = 0; i < moxtet->count; ++i)
moxtet->tx[moxtet->count - i] = bin[i];
err = spi_write(to_spi_device(moxtet->dev), moxtet->tx,
moxtet->count + 1);
mutex_unlock(&moxtet->lock);
return err < 0 ? err : len;
}
static const struct file_operations output_fops = {
.owner = THIS_MODULE,
.open = moxtet_debug_open,
.read = output_read,
.write = output_write,
};
static int moxtet_register_debugfs(struct moxtet *moxtet)
{
struct dentry *root, *entry;
root = debugfs_create_dir("moxtet", NULL);
if (IS_ERR(root))
return PTR_ERR(root);
entry = debugfs_create_file_unsafe("input", 0444, root, moxtet,
&input_fops);
if (IS_ERR(entry))
goto err_remove;
entry = debugfs_create_file_unsafe("output", 0644, root, moxtet,
&output_fops);
if (IS_ERR(entry))
goto err_remove;
moxtet->debugfs_root = root;
return 0;
err_remove:
debugfs_remove_recursive(root);
return PTR_ERR(entry);
}
static void moxtet_unregister_debugfs(struct moxtet *moxtet)
{
debugfs_remove_recursive(moxtet->debugfs_root);
}
#else
static inline int moxtet_register_debugfs(struct moxtet *moxtet)
{
return 0;
}
static inline void moxtet_unregister_debugfs(struct moxtet *moxtet)
{
}
#endif
static int moxtet_irq_domain_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
struct moxtet *moxtet = d->host_data;
if (hw >= MOXTET_NIRQS || !(moxtet->irq.exists & BIT(hw))) {
dev_err(moxtet->dev, "Invalid hw irq number\n");
return -EINVAL;
}
irq_set_chip_data(irq, d->host_data);
irq_set_chip_and_handler(irq, &moxtet->irq.chip, handle_level_irq);
return 0;
}
static int moxtet_irq_domain_xlate(struct irq_domain *d,
struct device_node *ctrlr,
const u32 *intspec, unsigned int intsize,
unsigned long *out_hwirq,
unsigned int *out_type)
{
struct moxtet *moxtet = d->host_data;
int irq;
if (WARN_ON(intsize < 1))
return -EINVAL;
irq = intspec[0];
if (irq >= MOXTET_NIRQS || !(moxtet->irq.exists & BIT(irq)))
return -EINVAL;
*out_hwirq = irq;
*out_type = IRQ_TYPE_NONE;
return 0;
}
static const struct irq_domain_ops moxtet_irq_domain = {
.map = moxtet_irq_domain_map,
.xlate = moxtet_irq_domain_xlate,
};
static void moxtet_irq_mask(struct irq_data *d)
{
struct moxtet *moxtet = irq_data_get_irq_chip_data(d);
moxtet->irq.masked |= BIT(d->hwirq);
}
static void moxtet_irq_unmask(struct irq_data *d)
{
struct moxtet *moxtet = irq_data_get_irq_chip_data(d);
moxtet->irq.masked &= ~BIT(d->hwirq);
}
static void moxtet_irq_print_chip(struct irq_data *d, struct seq_file *p)
{
struct moxtet *moxtet = irq_data_get_irq_chip_data(d);
struct moxtet_irqpos *pos = &moxtet->irq.position[d->hwirq];
int id;
id = moxtet->modules[pos->idx];
seq_printf(p, " moxtet-%s.%i#%i", mox_module_name(id), pos->idx,
pos->bit);
}
static const struct irq_chip moxtet_irq_chip = {
.name = "moxtet",
.irq_mask = moxtet_irq_mask,
.irq_unmask = moxtet_irq_unmask,
.irq_print_chip = moxtet_irq_print_chip,
};
static int moxtet_irq_read(struct moxtet *moxtet, unsigned long *map)
{
struct moxtet_irqpos *pos = moxtet->irq.position;
u8 buf[TURRIS_MOX_MAX_MODULES];
int i, ret;
ret = moxtet_spi_read(moxtet, buf);
if (ret < 0)
return ret;
*map = 0;
for_each_set_bit(i, &moxtet->irq.exists, MOXTET_NIRQS) {
if (!(buf[pos[i].idx + 1] & BIT(4 + pos[i].bit)))
set_bit(i, map);
}
return 0;
}
static irqreturn_t moxtet_irq_thread_fn(int irq, void *data)
{
struct moxtet *moxtet = data;
unsigned long set;
int nhandled = 0, i, sub_irq, ret;
ret = moxtet_irq_read(moxtet, &set);
if (ret < 0)
goto out;
set &= ~moxtet->irq.masked;
do {
for_each_set_bit(i, &set, MOXTET_NIRQS) {
sub_irq = irq_find_mapping(moxtet->irq.domain, i);
handle_nested_irq(sub_irq);
dev_dbg(moxtet->dev, "%i irq\n", i);
++nhandled;
}
ret = moxtet_irq_read(moxtet, &set);
if (ret < 0)
goto out;
set &= ~moxtet->irq.masked;
} while (set);
out:
return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
}
static void moxtet_irq_free(struct moxtet *moxtet)
{
int i, irq;
for (i = 0; i < MOXTET_NIRQS; ++i) {
if (moxtet->irq.exists & BIT(i)) {
irq = irq_find_mapping(moxtet->irq.domain, i);
irq_dispose_mapping(irq);
}
}
irq_domain_remove(moxtet->irq.domain);
}
static int moxtet_irq_setup(struct moxtet *moxtet)
{
int i, ret;
moxtet->irq.domain = irq_domain_add_simple(moxtet->dev->of_node,
MOXTET_NIRQS, 0,
&moxtet_irq_domain, moxtet);
if (moxtet->irq.domain == NULL) {
dev_err(moxtet->dev, "Could not add IRQ domain\n");
return -ENOMEM;
}
for (i = 0; i < MOXTET_NIRQS; ++i)
if (moxtet->irq.exists & BIT(i))
irq_create_mapping(moxtet->irq.domain, i);
moxtet->irq.chip = moxtet_irq_chip;
moxtet->irq.masked = ~0;
ret = request_threaded_irq(moxtet->dev_irq, NULL, moxtet_irq_thread_fn,
IRQF_SHARED | IRQF_ONESHOT, "moxtet", moxtet);
if (ret < 0)
goto err_free;
return 0;
err_free:
moxtet_irq_free(moxtet);
return ret;
}
static int moxtet_probe(struct spi_device *spi)
{
struct moxtet *moxtet;
int ret;
ret = spi_setup(spi);
if (ret < 0)
return ret;
moxtet = devm_kzalloc(&spi->dev, sizeof(struct moxtet),
GFP_KERNEL);
if (!moxtet)
return -ENOMEM;
moxtet->dev = &spi->dev;
spi_set_drvdata(spi, moxtet);
mutex_init(&moxtet->lock);
moxtet->dev_irq = of_irq_get(moxtet->dev->of_node, 0);
if (moxtet->dev_irq == -EPROBE_DEFER)
return -EPROBE_DEFER;
if (moxtet->dev_irq <= 0) {
dev_err(moxtet->dev, "No IRQ resource found\n");
return -ENXIO;
}
ret = moxtet_find_topology(moxtet);
if (ret < 0)
return ret;
if (moxtet->irq.exists) {
ret = moxtet_irq_setup(moxtet);
if (ret < 0)
return ret;
}
of_register_moxtet_devices(moxtet);
moxtet_register_devices_from_topology(moxtet);
ret = moxtet_register_debugfs(moxtet);
if (ret < 0)
dev_warn(moxtet->dev, "Failed creating debugfs entries: %i\n",
ret);
return 0;
}
static void moxtet_remove(struct spi_device *spi)
{
struct moxtet *moxtet = spi_get_drvdata(spi);
free_irq(moxtet->dev_irq, moxtet);
moxtet_irq_free(moxtet);
moxtet_unregister_debugfs(moxtet);
device_for_each_child(moxtet->dev, NULL, __unregister);
mutex_destroy(&moxtet->lock);
}
static const struct spi_device_id moxtet_spi_ids[] = {
{ "moxtet" },
{ },
};
MODULE_DEVICE_TABLE(spi, moxtet_spi_ids);
static const struct of_device_id moxtet_dt_ids[] = {
{ .compatible = "cznic,moxtet" },
{},
};
MODULE_DEVICE_TABLE(of, moxtet_dt_ids);
static struct spi_driver moxtet_spi_driver = {
.driver = {
.name = "moxtet",
.of_match_table = moxtet_dt_ids,
},
.id_table = moxtet_spi_ids,
.probe = moxtet_probe,
.remove = moxtet_remove,
};
static int __init moxtet_init(void)
{
int ret;
ret = bus_register(&moxtet_bus_type);
if (ret < 0) {
pr_err("moxtet bus registration failed: %d\n", ret);
goto error;
}
ret = spi_register_driver(&moxtet_spi_driver);
if (ret < 0) {
pr_err("moxtet spi driver registration failed: %d\n", ret);
goto error_bus;
}
return 0;
error_bus:
bus_unregister(&moxtet_bus_type);
error:
return ret;
}
postcore_initcall_sync(moxtet_init);
static void __exit moxtet_exit(void)
{
spi_unregister_driver(&moxtet_spi_driver);
bus_unregister(&moxtet_bus_type);
}
module_exit(moxtet_exit);
MODULE_AUTHOR("Marek Behun <[email protected]>");
MODULE_DESCRIPTION("CZ.NIC's Turris Mox module configuration bus");
MODULE_LICENSE("GPL v2");
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