diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/i3c/master.c | 2847 |
1 files changed, 2847 insertions, 0 deletions
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c new file mode 100644 index 000000000..ab0b5691b --- /dev/null +++ b/drivers/i3c/master.c @@ -0,0 +1,2847 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Cadence Design Systems Inc. + * + * Author: Boris Brezillon <boris.brezillon@bootlin.com> + */ + +#include <linux/atomic.h> +#include <linux/bug.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/workqueue.h> + +#include "internals.h" + +static DEFINE_IDR(i3c_bus_idr); +static DEFINE_MUTEX(i3c_core_lock); + +/** + * i3c_bus_maintenance_lock - Lock the bus for a maintenance operation + * @bus: I3C bus to take the lock on + * + * This function takes the bus lock so that no other operations can occur on + * the bus. This is needed for all kind of bus maintenance operation, like + * - enabling/disabling slave events + * - re-triggering DAA + * - changing the dynamic address of a device + * - relinquishing mastership + * - ... + * + * The reason for this kind of locking is that we don't want drivers and core + * logic to rely on I3C device information that could be changed behind their + * back. + */ +static void i3c_bus_maintenance_lock(struct i3c_bus *bus) +{ + down_write(&bus->lock); +} + +/** + * i3c_bus_maintenance_unlock - Release the bus lock after a maintenance + * operation + * @bus: I3C bus to release the lock on + * + * Should be called when the bus maintenance operation is done. See + * i3c_bus_maintenance_lock() for more details on what these maintenance + * operations are. + */ +static void i3c_bus_maintenance_unlock(struct i3c_bus *bus) +{ + up_write(&bus->lock); +} + +/** + * i3c_bus_normaluse_lock - Lock the bus for a normal operation + * @bus: I3C bus to take the lock on + * + * This function takes the bus lock for any operation that is not a maintenance + * operation (see i3c_bus_maintenance_lock() for a non-exhaustive list of + * maintenance operations). Basically all communications with I3C devices are + * normal operations (HDR, SDR transfers or CCC commands that do not change bus + * state or I3C dynamic address). + * + * Note that this lock is not guaranteeing serialization of normal operations. + * In other words, transfer requests passed to the I3C master can be submitted + * in parallel and I3C master drivers have to use their own locking to make + * sure two different communications are not inter-mixed, or access to the + * output/input queue is not done while the engine is busy. + */ +void i3c_bus_normaluse_lock(struct i3c_bus *bus) +{ + down_read(&bus->lock); +} + +/** + * i3c_bus_normaluse_unlock - Release the bus lock after a normal operation + * @bus: I3C bus to release the lock on + * + * Should be called when a normal operation is done. See + * i3c_bus_normaluse_lock() for more details on what these normal operations + * are. + */ +void i3c_bus_normaluse_unlock(struct i3c_bus *bus) +{ + up_read(&bus->lock); +} + +static struct i3c_master_controller * +i3c_bus_to_i3c_master(struct i3c_bus *i3cbus) +{ + return container_of(i3cbus, struct i3c_master_controller, bus); +} + +static struct i3c_master_controller *dev_to_i3cmaster(struct device *dev) +{ + return container_of(dev, struct i3c_master_controller, dev); +} + +static const struct device_type i3c_device_type; + +static struct i3c_bus *dev_to_i3cbus(struct device *dev) +{ + struct i3c_master_controller *master; + + if (dev->type == &i3c_device_type) + return dev_to_i3cdev(dev)->bus; + + master = dev_to_i3cmaster(dev); + + return &master->bus; +} + +static struct i3c_dev_desc *dev_to_i3cdesc(struct device *dev) +{ + struct i3c_master_controller *master; + + if (dev->type == &i3c_device_type) + return dev_to_i3cdev(dev)->desc; + + master = dev_to_i3cmaster(dev); + + return master->this; +} + +static ssize_t bcr_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *bus = dev_to_i3cbus(dev); + struct i3c_dev_desc *desc; + ssize_t ret; + + i3c_bus_normaluse_lock(bus); + desc = dev_to_i3cdesc(dev); + ret = sprintf(buf, "%x\n", desc->info.bcr); + i3c_bus_normaluse_unlock(bus); + + return ret; +} +static DEVICE_ATTR_RO(bcr); + +static ssize_t dcr_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *bus = dev_to_i3cbus(dev); + struct i3c_dev_desc *desc; + ssize_t ret; + + i3c_bus_normaluse_lock(bus); + desc = dev_to_i3cdesc(dev); + ret = sprintf(buf, "%x\n", desc->info.dcr); + i3c_bus_normaluse_unlock(bus); + + return ret; +} +static DEVICE_ATTR_RO(dcr); + +static ssize_t pid_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *bus = dev_to_i3cbus(dev); + struct i3c_dev_desc *desc; + ssize_t ret; + + i3c_bus_normaluse_lock(bus); + desc = dev_to_i3cdesc(dev); + ret = sprintf(buf, "%llx\n", desc->info.pid); + i3c_bus_normaluse_unlock(bus); + + return ret; +} +static DEVICE_ATTR_RO(pid); + +static ssize_t dynamic_address_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *bus = dev_to_i3cbus(dev); + struct i3c_dev_desc *desc; + ssize_t ret; + + i3c_bus_normaluse_lock(bus); + desc = dev_to_i3cdesc(dev); + ret = sprintf(buf, "%02x\n", desc->info.dyn_addr); + i3c_bus_normaluse_unlock(bus); + + return ret; +} +static DEVICE_ATTR_RO(dynamic_address); + +static const char * const hdrcap_strings[] = { + "hdr-ddr", "hdr-tsp", "hdr-tsl", +}; + +static ssize_t hdrcap_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *bus = dev_to_i3cbus(dev); + struct i3c_dev_desc *desc; + ssize_t offset = 0, ret; + unsigned long caps; + int mode; + + i3c_bus_normaluse_lock(bus); + desc = dev_to_i3cdesc(dev); + caps = desc->info.hdr_cap; + for_each_set_bit(mode, &caps, 8) { + if (mode >= ARRAY_SIZE(hdrcap_strings)) + break; + + if (!hdrcap_strings[mode]) + continue; + + ret = sprintf(buf + offset, offset ? " %s" : "%s", + hdrcap_strings[mode]); + if (ret < 0) + goto out; + + offset += ret; + } + + ret = sprintf(buf + offset, "\n"); + if (ret < 0) + goto out; + + ret = offset + ret; + +out: + i3c_bus_normaluse_unlock(bus); + + return ret; +} +static DEVICE_ATTR_RO(hdrcap); + +static ssize_t modalias_show(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct i3c_device *i3c = dev_to_i3cdev(dev); + struct i3c_device_info devinfo; + u16 manuf, part, ext; + + i3c_device_get_info(i3c, &devinfo); + manuf = I3C_PID_MANUF_ID(devinfo.pid); + part = I3C_PID_PART_ID(devinfo.pid); + ext = I3C_PID_EXTRA_INFO(devinfo.pid); + + if (I3C_PID_RND_LOWER_32BITS(devinfo.pid)) + return sprintf(buf, "i3c:dcr%02Xmanuf%04X", devinfo.dcr, + manuf); + + return sprintf(buf, "i3c:dcr%02Xmanuf%04Xpart%04Xext%04X", + devinfo.dcr, manuf, part, ext); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *i3c_device_attrs[] = { + &dev_attr_bcr.attr, + &dev_attr_dcr.attr, + &dev_attr_pid.attr, + &dev_attr_dynamic_address.attr, + &dev_attr_hdrcap.attr, + &dev_attr_modalias.attr, + NULL, +}; +ATTRIBUTE_GROUPS(i3c_device); + +static int i3c_device_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct i3c_device *i3cdev = dev_to_i3cdev(dev); + struct i3c_device_info devinfo; + u16 manuf, part, ext; + + i3c_device_get_info(i3cdev, &devinfo); + manuf = I3C_PID_MANUF_ID(devinfo.pid); + part = I3C_PID_PART_ID(devinfo.pid); + ext = I3C_PID_EXTRA_INFO(devinfo.pid); + + if (I3C_PID_RND_LOWER_32BITS(devinfo.pid)) + return add_uevent_var(env, "MODALIAS=i3c:dcr%02Xmanuf%04X", + devinfo.dcr, manuf); + + return add_uevent_var(env, + "MODALIAS=i3c:dcr%02Xmanuf%04Xpart%04Xext%04X", + devinfo.dcr, manuf, part, ext); +} + +static const struct device_type i3c_device_type = { + .groups = i3c_device_groups, + .uevent = i3c_device_uevent, +}; + +static int i3c_device_match(struct device *dev, struct device_driver *drv) +{ + struct i3c_device *i3cdev; + struct i3c_driver *i3cdrv; + + if (dev->type != &i3c_device_type) + return 0; + + i3cdev = dev_to_i3cdev(dev); + i3cdrv = drv_to_i3cdrv(drv); + if (i3c_device_match_id(i3cdev, i3cdrv->id_table)) + return 1; + + return 0; +} + +static int i3c_device_probe(struct device *dev) +{ + struct i3c_device *i3cdev = dev_to_i3cdev(dev); + struct i3c_driver *driver = drv_to_i3cdrv(dev->driver); + + return driver->probe(i3cdev); +} + +static void i3c_device_remove(struct device *dev) +{ + struct i3c_device *i3cdev = dev_to_i3cdev(dev); + struct i3c_driver *driver = drv_to_i3cdrv(dev->driver); + + if (driver->remove) + driver->remove(i3cdev); + + i3c_device_free_ibi(i3cdev); +} + +struct bus_type i3c_bus_type = { + .name = "i3c", + .match = i3c_device_match, + .probe = i3c_device_probe, + .remove = i3c_device_remove, +}; + +static enum i3c_addr_slot_status +i3c_bus_get_addr_slot_status(struct i3c_bus *bus, u16 addr) +{ + unsigned long status; + int bitpos = addr * 2; + + if (addr > I2C_MAX_ADDR) + return I3C_ADDR_SLOT_RSVD; + + status = bus->addrslots[bitpos / BITS_PER_LONG]; + status >>= bitpos % BITS_PER_LONG; + + return status & I3C_ADDR_SLOT_STATUS_MASK; +} + +static void i3c_bus_set_addr_slot_status(struct i3c_bus *bus, u16 addr, + enum i3c_addr_slot_status status) +{ + int bitpos = addr * 2; + unsigned long *ptr; + + if (addr > I2C_MAX_ADDR) + return; + + ptr = bus->addrslots + (bitpos / BITS_PER_LONG); + *ptr &= ~((unsigned long)I3C_ADDR_SLOT_STATUS_MASK << + (bitpos % BITS_PER_LONG)); + *ptr |= (unsigned long)status << (bitpos % BITS_PER_LONG); +} + +static bool i3c_bus_dev_addr_is_avail(struct i3c_bus *bus, u8 addr) +{ + enum i3c_addr_slot_status status; + + status = i3c_bus_get_addr_slot_status(bus, addr); + + return status == I3C_ADDR_SLOT_FREE; +} + +static int i3c_bus_get_free_addr(struct i3c_bus *bus, u8 start_addr) +{ + enum i3c_addr_slot_status status; + u8 addr; + + for (addr = start_addr; addr < I3C_MAX_ADDR; addr++) { + status = i3c_bus_get_addr_slot_status(bus, addr); + if (status == I3C_ADDR_SLOT_FREE) + return addr; + } + + return -ENOMEM; +} + +static void i3c_bus_init_addrslots(struct i3c_bus *bus) +{ + int i; + + /* Addresses 0 to 7 are reserved. */ + for (i = 0; i < 8; i++) + i3c_bus_set_addr_slot_status(bus, i, I3C_ADDR_SLOT_RSVD); + + /* + * Reserve broadcast address and all addresses that might collide + * with the broadcast address when facing a single bit error. + */ + i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR, + I3C_ADDR_SLOT_RSVD); + for (i = 0; i < 7; i++) + i3c_bus_set_addr_slot_status(bus, I3C_BROADCAST_ADDR ^ BIT(i), + I3C_ADDR_SLOT_RSVD); +} + +static void i3c_bus_cleanup(struct i3c_bus *i3cbus) +{ + mutex_lock(&i3c_core_lock); + idr_remove(&i3c_bus_idr, i3cbus->id); + mutex_unlock(&i3c_core_lock); +} + +static int i3c_bus_init(struct i3c_bus *i3cbus) +{ + int ret; + + init_rwsem(&i3cbus->lock); + INIT_LIST_HEAD(&i3cbus->devs.i2c); + INIT_LIST_HEAD(&i3cbus->devs.i3c); + i3c_bus_init_addrslots(i3cbus); + i3cbus->mode = I3C_BUS_MODE_PURE; + + mutex_lock(&i3c_core_lock); + ret = idr_alloc(&i3c_bus_idr, i3cbus, 0, 0, GFP_KERNEL); + mutex_unlock(&i3c_core_lock); + + if (ret < 0) + return ret; + + i3cbus->id = ret; + + return 0; +} + +static const char * const i3c_bus_mode_strings[] = { + [I3C_BUS_MODE_PURE] = "pure", + [I3C_BUS_MODE_MIXED_FAST] = "mixed-fast", + [I3C_BUS_MODE_MIXED_LIMITED] = "mixed-limited", + [I3C_BUS_MODE_MIXED_SLOW] = "mixed-slow", +}; + +static ssize_t mode_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *i3cbus = dev_to_i3cbus(dev); + ssize_t ret; + + i3c_bus_normaluse_lock(i3cbus); + if (i3cbus->mode < 0 || + i3cbus->mode >= ARRAY_SIZE(i3c_bus_mode_strings) || + !i3c_bus_mode_strings[i3cbus->mode]) + ret = sprintf(buf, "unknown\n"); + else + ret = sprintf(buf, "%s\n", i3c_bus_mode_strings[i3cbus->mode]); + i3c_bus_normaluse_unlock(i3cbus); + + return ret; +} +static DEVICE_ATTR_RO(mode); + +static ssize_t current_master_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *i3cbus = dev_to_i3cbus(dev); + ssize_t ret; + + i3c_bus_normaluse_lock(i3cbus); + ret = sprintf(buf, "%d-%llx\n", i3cbus->id, + i3cbus->cur_master->info.pid); + i3c_bus_normaluse_unlock(i3cbus); + + return ret; +} +static DEVICE_ATTR_RO(current_master); + +static ssize_t i3c_scl_frequency_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *i3cbus = dev_to_i3cbus(dev); + ssize_t ret; + + i3c_bus_normaluse_lock(i3cbus); + ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i3c); + i3c_bus_normaluse_unlock(i3cbus); + + return ret; +} +static DEVICE_ATTR_RO(i3c_scl_frequency); + +static ssize_t i2c_scl_frequency_show(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct i3c_bus *i3cbus = dev_to_i3cbus(dev); + ssize_t ret; + + i3c_bus_normaluse_lock(i3cbus); + ret = sprintf(buf, "%ld\n", i3cbus->scl_rate.i2c); + i3c_bus_normaluse_unlock(i3cbus); + + return ret; +} +static DEVICE_ATTR_RO(i2c_scl_frequency); + +static struct attribute *i3c_masterdev_attrs[] = { + &dev_attr_mode.attr, + &dev_attr_current_master.attr, + &dev_attr_i3c_scl_frequency.attr, + &dev_attr_i2c_scl_frequency.attr, + &dev_attr_bcr.attr, + &dev_attr_dcr.attr, + &dev_attr_pid.attr, + &dev_attr_dynamic_address.attr, + &dev_attr_hdrcap.attr, + NULL, +}; +ATTRIBUTE_GROUPS(i3c_masterdev); + +static void i3c_masterdev_release(struct device *dev) +{ + struct i3c_master_controller *master = dev_to_i3cmaster(dev); + struct i3c_bus *bus = dev_to_i3cbus(dev); + + if (master->wq) + destroy_workqueue(master->wq); + + WARN_ON(!list_empty(&bus->devs.i2c) || !list_empty(&bus->devs.i3c)); + i3c_bus_cleanup(bus); + + of_node_put(dev->of_node); +} + +static const struct device_type i3c_masterdev_type = { + .groups = i3c_masterdev_groups, +}; + +static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode, + unsigned long max_i2c_scl_rate) +{ + struct i3c_master_controller *master = i3c_bus_to_i3c_master(i3cbus); + + i3cbus->mode = mode; + + switch (i3cbus->mode) { + case I3C_BUS_MODE_PURE: + if (!i3cbus->scl_rate.i3c) + i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE; + break; + case I3C_BUS_MODE_MIXED_FAST: + case I3C_BUS_MODE_MIXED_LIMITED: + if (!i3cbus->scl_rate.i3c) + i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE; + if (!i3cbus->scl_rate.i2c) + i3cbus->scl_rate.i2c = max_i2c_scl_rate; + break; + case I3C_BUS_MODE_MIXED_SLOW: + if (!i3cbus->scl_rate.i2c) + i3cbus->scl_rate.i2c = max_i2c_scl_rate; + if (!i3cbus->scl_rate.i3c || + i3cbus->scl_rate.i3c > i3cbus->scl_rate.i2c) + i3cbus->scl_rate.i3c = i3cbus->scl_rate.i2c; + break; + default: + return -EINVAL; + } + + dev_dbg(&master->dev, "i2c-scl = %ld Hz i3c-scl = %ld Hz\n", + i3cbus->scl_rate.i2c, i3cbus->scl_rate.i3c); + + /* + * I3C/I2C frequency may have been overridden, check that user-provided + * values are not exceeding max possible frequency. + */ + if (i3cbus->scl_rate.i3c > I3C_BUS_MAX_I3C_SCL_RATE || + i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_RATE) + return -EINVAL; + + return 0; +} + +static struct i3c_master_controller * +i2c_adapter_to_i3c_master(struct i2c_adapter *adap) +{ + return container_of(adap, struct i3c_master_controller, i2c); +} + +static struct i2c_adapter * +i3c_master_to_i2c_adapter(struct i3c_master_controller *master) +{ + return &master->i2c; +} + +static void i3c_master_free_i2c_dev(struct i2c_dev_desc *dev) +{ + kfree(dev); +} + +static struct i2c_dev_desc * +i3c_master_alloc_i2c_dev(struct i3c_master_controller *master, + u16 addr, u8 lvr) +{ + struct i2c_dev_desc *dev; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return ERR_PTR(-ENOMEM); + + dev->common.master = master; + dev->addr = addr; + dev->lvr = lvr; + + return dev; +} + +static void *i3c_ccc_cmd_dest_init(struct i3c_ccc_cmd_dest *dest, u8 addr, + u16 payloadlen) +{ + dest->addr = addr; + dest->payload.len = payloadlen; + if (payloadlen) + dest->payload.data = kzalloc(payloadlen, GFP_KERNEL); + else + dest->payload.data = NULL; + + return dest->payload.data; +} + +static void i3c_ccc_cmd_dest_cleanup(struct i3c_ccc_cmd_dest *dest) +{ + kfree(dest->payload.data); +} + +static void i3c_ccc_cmd_init(struct i3c_ccc_cmd *cmd, bool rnw, u8 id, + struct i3c_ccc_cmd_dest *dests, + unsigned int ndests) +{ + cmd->rnw = rnw ? 1 : 0; + cmd->id = id; + cmd->dests = dests; + cmd->ndests = ndests; + cmd->err = I3C_ERROR_UNKNOWN; +} + +static int i3c_master_send_ccc_cmd_locked(struct i3c_master_controller *master, + struct i3c_ccc_cmd *cmd) +{ + int ret; + + if (!cmd || !master) + return -EINVAL; + + if (WARN_ON(master->init_done && + !rwsem_is_locked(&master->bus.lock))) + return -EINVAL; + + if (!master->ops->send_ccc_cmd) + return -ENOTSUPP; + + if ((cmd->id & I3C_CCC_DIRECT) && (!cmd->dests || !cmd->ndests)) + return -EINVAL; + + if (master->ops->supports_ccc_cmd && + !master->ops->supports_ccc_cmd(master, cmd)) + return -ENOTSUPP; + + ret = master->ops->send_ccc_cmd(master, cmd); + if (ret) { + if (cmd->err != I3C_ERROR_UNKNOWN) + return cmd->err; + + return ret; + } + + return 0; +} + +static struct i2c_dev_desc * +i3c_master_find_i2c_dev_by_addr(const struct i3c_master_controller *master, + u16 addr) +{ + struct i2c_dev_desc *dev; + + i3c_bus_for_each_i2cdev(&master->bus, dev) { + if (dev->addr == addr) + return dev; + } + + return NULL; +} + +/** + * i3c_master_get_free_addr() - get a free address on the bus + * @master: I3C master object + * @start_addr: where to start searching + * + * This function must be called with the bus lock held in write mode. + * + * Return: the first free address starting at @start_addr (included) or -ENOMEM + * if there's no more address available. + */ +int i3c_master_get_free_addr(struct i3c_master_controller *master, + u8 start_addr) +{ + return i3c_bus_get_free_addr(&master->bus, start_addr); +} +EXPORT_SYMBOL_GPL(i3c_master_get_free_addr); + +static void i3c_device_release(struct device *dev) +{ + struct i3c_device *i3cdev = dev_to_i3cdev(dev); + + WARN_ON(i3cdev->desc); + + of_node_put(i3cdev->dev.of_node); + kfree(i3cdev); +} + +static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev) +{ + kfree(dev); +} + +static struct i3c_dev_desc * +i3c_master_alloc_i3c_dev(struct i3c_master_controller *master, + const struct i3c_device_info *info) +{ + struct i3c_dev_desc *dev; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return ERR_PTR(-ENOMEM); + + dev->common.master = master; + dev->info = *info; + mutex_init(&dev->ibi_lock); + + return dev; +} + +static int i3c_master_rstdaa_locked(struct i3c_master_controller *master, + u8 addr) +{ + enum i3c_addr_slot_status addrstat; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + if (!master) + return -EINVAL; + + addrstat = i3c_bus_get_addr_slot_status(&master->bus, addr); + if (addr != I3C_BROADCAST_ADDR && addrstat != I3C_ADDR_SLOT_I3C_DEV) + return -EINVAL; + + i3c_ccc_cmd_dest_init(&dest, addr, 0); + i3c_ccc_cmd_init(&cmd, false, + I3C_CCC_RSTDAA(addr == I3C_BROADCAST_ADDR), + &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +/** + * i3c_master_entdaa_locked() - start a DAA (Dynamic Address Assignment) + * procedure + * @master: master used to send frames on the bus + * + * Send a ENTDAA CCC command to start a DAA procedure. + * + * Note that this function only sends the ENTDAA CCC command, all the logic + * behind dynamic address assignment has to be handled in the I3C master + * driver. + * + * This function must be called with the bus lock held in write mode. + * + * Return: 0 in case of success, a positive I3C error code if the error is + * one of the official Mx error codes, and a negative error code otherwise. + */ +int i3c_master_entdaa_locked(struct i3c_master_controller *master) +{ + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR, 0); + i3c_ccc_cmd_init(&cmd, false, I3C_CCC_ENTDAA, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_entdaa_locked); + +static int i3c_master_enec_disec_locked(struct i3c_master_controller *master, + u8 addr, bool enable, u8 evts) +{ + struct i3c_ccc_events *events; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + events = i3c_ccc_cmd_dest_init(&dest, addr, sizeof(*events)); + if (!events) + return -ENOMEM; + + events->events = evts; + i3c_ccc_cmd_init(&cmd, false, + enable ? + I3C_CCC_ENEC(addr == I3C_BROADCAST_ADDR) : + I3C_CCC_DISEC(addr == I3C_BROADCAST_ADDR), + &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +/** + * i3c_master_disec_locked() - send a DISEC CCC command + * @master: master used to send frames on the bus + * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR + * @evts: events to disable + * + * Send a DISEC CCC command to disable some or all events coming from a + * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR. + * + * This function must be called with the bus lock held in write mode. + * + * Return: 0 in case of success, a positive I3C error code if the error is + * one of the official Mx error codes, and a negative error code otherwise. + */ +int i3c_master_disec_locked(struct i3c_master_controller *master, u8 addr, + u8 evts) +{ + return i3c_master_enec_disec_locked(master, addr, false, evts); +} +EXPORT_SYMBOL_GPL(i3c_master_disec_locked); + +/** + * i3c_master_enec_locked() - send an ENEC CCC command + * @master: master used to send frames on the bus + * @addr: a valid I3C slave address or %I3C_BROADCAST_ADDR + * @evts: events to disable + * + * Sends an ENEC CCC command to enable some or all events coming from a + * specific slave, or all devices if @addr is %I3C_BROADCAST_ADDR. + * + * This function must be called with the bus lock held in write mode. + * + * Return: 0 in case of success, a positive I3C error code if the error is + * one of the official Mx error codes, and a negative error code otherwise. + */ +int i3c_master_enec_locked(struct i3c_master_controller *master, u8 addr, + u8 evts) +{ + return i3c_master_enec_disec_locked(master, addr, true, evts); +} +EXPORT_SYMBOL_GPL(i3c_master_enec_locked); + +/** + * i3c_master_defslvs_locked() - send a DEFSLVS CCC command + * @master: master used to send frames on the bus + * + * Send a DEFSLVS CCC command containing all the devices known to the @master. + * This is useful when you have secondary masters on the bus to propagate + * device information. + * + * This should be called after all I3C devices have been discovered (in other + * words, after the DAA procedure has finished) and instantiated in + * &i3c_master_controller_ops->bus_init(). + * It should also be called if a master ACKed an Hot-Join request and assigned + * a dynamic address to the device joining the bus. + * + * This function must be called with the bus lock held in write mode. + * + * Return: 0 in case of success, a positive I3C error code if the error is + * one of the official Mx error codes, and a negative error code otherwise. + */ +int i3c_master_defslvs_locked(struct i3c_master_controller *master) +{ + struct i3c_ccc_defslvs *defslvs; + struct i3c_ccc_dev_desc *desc; + struct i3c_ccc_cmd_dest dest; + struct i3c_dev_desc *i3cdev; + struct i2c_dev_desc *i2cdev; + struct i3c_ccc_cmd cmd; + struct i3c_bus *bus; + bool send = false; + int ndevs = 0, ret; + + if (!master) + return -EINVAL; + + bus = i3c_master_get_bus(master); + i3c_bus_for_each_i3cdev(bus, i3cdev) { + ndevs++; + + if (i3cdev == master->this) + continue; + + if (I3C_BCR_DEVICE_ROLE(i3cdev->info.bcr) == + I3C_BCR_I3C_MASTER) + send = true; + } + + /* No other master on the bus, skip DEFSLVS. */ + if (!send) + return 0; + + i3c_bus_for_each_i2cdev(bus, i2cdev) + ndevs++; + + defslvs = i3c_ccc_cmd_dest_init(&dest, I3C_BROADCAST_ADDR, + struct_size(defslvs, slaves, + ndevs - 1)); + if (!defslvs) + return -ENOMEM; + + defslvs->count = ndevs; + defslvs->master.bcr = master->this->info.bcr; + defslvs->master.dcr = master->this->info.dcr; + defslvs->master.dyn_addr = master->this->info.dyn_addr << 1; + defslvs->master.static_addr = I3C_BROADCAST_ADDR << 1; + + desc = defslvs->slaves; + i3c_bus_for_each_i2cdev(bus, i2cdev) { + desc->lvr = i2cdev->lvr; + desc->static_addr = i2cdev->addr << 1; + desc++; + } + + i3c_bus_for_each_i3cdev(bus, i3cdev) { + /* Skip the I3C dev representing this master. */ + if (i3cdev == master->this) + continue; + + desc->bcr = i3cdev->info.bcr; + desc->dcr = i3cdev->info.dcr; + desc->dyn_addr = i3cdev->info.dyn_addr << 1; + desc->static_addr = i3cdev->info.static_addr << 1; + desc++; + } + + i3c_ccc_cmd_init(&cmd, false, I3C_CCC_DEFSLVS, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_defslvs_locked); + +static int i3c_master_setda_locked(struct i3c_master_controller *master, + u8 oldaddr, u8 newaddr, bool setdasa) +{ + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_setda *setda; + struct i3c_ccc_cmd cmd; + int ret; + + if (!oldaddr || !newaddr) + return -EINVAL; + + setda = i3c_ccc_cmd_dest_init(&dest, oldaddr, sizeof(*setda)); + if (!setda) + return -ENOMEM; + + setda->addr = newaddr << 1; + i3c_ccc_cmd_init(&cmd, false, + setdasa ? I3C_CCC_SETDASA : I3C_CCC_SETNEWDA, + &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_setdasa_locked(struct i3c_master_controller *master, + u8 static_addr, u8 dyn_addr) +{ + return i3c_master_setda_locked(master, static_addr, dyn_addr, true); +} + +static int i3c_master_setnewda_locked(struct i3c_master_controller *master, + u8 oldaddr, u8 newaddr) +{ + return i3c_master_setda_locked(master, oldaddr, newaddr, false); +} + +static int i3c_master_getmrl_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_mrl *mrl; + struct i3c_ccc_cmd cmd; + int ret; + + mrl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mrl)); + if (!mrl) + return -ENOMEM; + + /* + * When the device does not have IBI payload GETMRL only returns 2 + * bytes of data. + */ + if (!(info->bcr & I3C_BCR_IBI_PAYLOAD)) + dest.payload.len -= 1; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMRL, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + switch (dest.payload.len) { + case 3: + info->max_ibi_len = mrl->ibi_len; + fallthrough; + case 2: + info->max_read_len = be16_to_cpu(mrl->read_len); + break; + default: + ret = -EIO; + goto out; + } + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_getmwl_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_mwl *mwl; + struct i3c_ccc_cmd cmd; + int ret; + + mwl = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*mwl)); + if (!mwl) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMWL, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + if (dest.payload.len != sizeof(*mwl)) { + ret = -EIO; + goto out; + } + + info->max_write_len = be16_to_cpu(mwl->len); + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_getmxds_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_getmxds *getmaxds; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + getmaxds = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, + sizeof(*getmaxds)); + if (!getmaxds) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + if (dest.payload.len != 2 && dest.payload.len != 5) { + ret = -EIO; + goto out; + } + + info->max_read_ds = getmaxds->maxrd; + info->max_write_ds = getmaxds->maxwr; + if (dest.payload.len == 5) + info->max_read_turnaround = getmaxds->maxrdturn[0] | + ((u32)getmaxds->maxrdturn[1] << 8) | + ((u32)getmaxds->maxrdturn[2] << 16); + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_gethdrcap_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_gethdrcap *gethdrcap; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + gethdrcap = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, + sizeof(*gethdrcap)); + if (!gethdrcap) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETHDRCAP, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + if (dest.payload.len != 1) { + ret = -EIO; + goto out; + } + + info->hdr_cap = gethdrcap->modes; + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_getpid_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_getpid *getpid; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret, i; + + getpid = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getpid)); + if (!getpid) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETPID, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + info->pid = 0; + for (i = 0; i < sizeof(getpid->pid); i++) { + int sft = (sizeof(getpid->pid) - i - 1) * 8; + + info->pid |= (u64)getpid->pid[i] << sft; + } + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_getbcr_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_getbcr *getbcr; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + getbcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getbcr)); + if (!getbcr) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETBCR, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + info->bcr = getbcr->bcr; + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_getdcr_locked(struct i3c_master_controller *master, + struct i3c_device_info *info) +{ + struct i3c_ccc_getdcr *getdcr; + struct i3c_ccc_cmd_dest dest; + struct i3c_ccc_cmd cmd; + int ret; + + getdcr = i3c_ccc_cmd_dest_init(&dest, info->dyn_addr, sizeof(*getdcr)); + if (!getdcr) + return -ENOMEM; + + i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETDCR, &dest, 1); + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + + info->dcr = getdcr->dcr; + +out: + i3c_ccc_cmd_dest_cleanup(&dest); + + return ret; +} + +static int i3c_master_retrieve_dev_info(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + enum i3c_addr_slot_status slot_status; + int ret; + + if (!dev->info.dyn_addr) + return -EINVAL; + + slot_status = i3c_bus_get_addr_slot_status(&master->bus, + dev->info.dyn_addr); + if (slot_status == I3C_ADDR_SLOT_RSVD || + slot_status == I3C_ADDR_SLOT_I2C_DEV) + return -EINVAL; + + ret = i3c_master_getpid_locked(master, &dev->info); + if (ret) + return ret; + + ret = i3c_master_getbcr_locked(master, &dev->info); + if (ret) + return ret; + + ret = i3c_master_getdcr_locked(master, &dev->info); + if (ret) + return ret; + + if (dev->info.bcr & I3C_BCR_MAX_DATA_SPEED_LIM) { + ret = i3c_master_getmxds_locked(master, &dev->info); + if (ret) + return ret; + } + + if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD) + dev->info.max_ibi_len = 1; + + i3c_master_getmrl_locked(master, &dev->info); + i3c_master_getmwl_locked(master, &dev->info); + + if (dev->info.bcr & I3C_BCR_HDR_CAP) { + ret = i3c_master_gethdrcap_locked(master, &dev->info); + if (ret) + return ret; + } + + return 0; +} + +static void i3c_master_put_i3c_addrs(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + + if (dev->info.static_addr) + i3c_bus_set_addr_slot_status(&master->bus, + dev->info.static_addr, + I3C_ADDR_SLOT_FREE); + + if (dev->info.dyn_addr) + i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr, + I3C_ADDR_SLOT_FREE); + + if (dev->boardinfo && dev->boardinfo->init_dyn_addr) + i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr, + I3C_ADDR_SLOT_FREE); +} + +static int i3c_master_get_i3c_addrs(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + enum i3c_addr_slot_status status; + + if (!dev->info.static_addr && !dev->info.dyn_addr) + return 0; + + if (dev->info.static_addr) { + status = i3c_bus_get_addr_slot_status(&master->bus, + dev->info.static_addr); + if (status != I3C_ADDR_SLOT_FREE) + return -EBUSY; + + i3c_bus_set_addr_slot_status(&master->bus, + dev->info.static_addr, + I3C_ADDR_SLOT_I3C_DEV); + } + + /* + * ->init_dyn_addr should have been reserved before that, so, if we're + * trying to apply a pre-reserved dynamic address, we should not try + * to reserve the address slot a second time. + */ + if (dev->info.dyn_addr && + (!dev->boardinfo || + dev->boardinfo->init_dyn_addr != dev->info.dyn_addr)) { + status = i3c_bus_get_addr_slot_status(&master->bus, + dev->info.dyn_addr); + if (status != I3C_ADDR_SLOT_FREE) + goto err_release_static_addr; + + i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr, + I3C_ADDR_SLOT_I3C_DEV); + } + + return 0; + +err_release_static_addr: + if (dev->info.static_addr) + i3c_bus_set_addr_slot_status(&master->bus, + dev->info.static_addr, + I3C_ADDR_SLOT_FREE); + + return -EBUSY; +} + +static int i3c_master_attach_i3c_dev(struct i3c_master_controller *master, + struct i3c_dev_desc *dev) +{ + int ret; + + /* + * We don't attach devices to the controller until they are + * addressable on the bus. + */ + if (!dev->info.static_addr && !dev->info.dyn_addr) + return 0; + + ret = i3c_master_get_i3c_addrs(dev); + if (ret) + return ret; + + /* Do not attach the master device itself. */ + if (master->this != dev && master->ops->attach_i3c_dev) { + ret = master->ops->attach_i3c_dev(dev); + if (ret) { + i3c_master_put_i3c_addrs(dev); + return ret; + } + } + + list_add_tail(&dev->common.node, &master->bus.devs.i3c); + + return 0; +} + +static int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev, + u8 old_dyn_addr) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + enum i3c_addr_slot_status status; + int ret; + + if (dev->info.dyn_addr != old_dyn_addr && + (!dev->boardinfo || + dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) { + status = i3c_bus_get_addr_slot_status(&master->bus, + dev->info.dyn_addr); + if (status != I3C_ADDR_SLOT_FREE) + return -EBUSY; + i3c_bus_set_addr_slot_status(&master->bus, + dev->info.dyn_addr, + I3C_ADDR_SLOT_I3C_DEV); + if (old_dyn_addr) + i3c_bus_set_addr_slot_status(&master->bus, old_dyn_addr, + I3C_ADDR_SLOT_FREE); + } + + if (master->ops->reattach_i3c_dev) { + ret = master->ops->reattach_i3c_dev(dev, old_dyn_addr); + if (ret) { + i3c_master_put_i3c_addrs(dev); + return ret; + } + } + + return 0; +} + +static void i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + + /* Do not detach the master device itself. */ + if (master->this != dev && master->ops->detach_i3c_dev) + master->ops->detach_i3c_dev(dev); + + i3c_master_put_i3c_addrs(dev); + list_del(&dev->common.node); +} + +static int i3c_master_attach_i2c_dev(struct i3c_master_controller *master, + struct i2c_dev_desc *dev) +{ + int ret; + + if (master->ops->attach_i2c_dev) { + ret = master->ops->attach_i2c_dev(dev); + if (ret) + return ret; + } + + list_add_tail(&dev->common.node, &master->bus.devs.i2c); + + return 0; +} + +static void i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev) +{ + struct i3c_master_controller *master = i2c_dev_get_master(dev); + + list_del(&dev->common.node); + + if (master->ops->detach_i2c_dev) + master->ops->detach_i2c_dev(dev); +} + +static int i3c_master_early_i3c_dev_add(struct i3c_master_controller *master, + struct i3c_dev_boardinfo *boardinfo) +{ + struct i3c_device_info info = { + .static_addr = boardinfo->static_addr, + }; + struct i3c_dev_desc *i3cdev; + int ret; + + i3cdev = i3c_master_alloc_i3c_dev(master, &info); + if (IS_ERR(i3cdev)) + return -ENOMEM; + + i3cdev->boardinfo = boardinfo; + + ret = i3c_master_attach_i3c_dev(master, i3cdev); + if (ret) + goto err_free_dev; + + ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr, + i3cdev->boardinfo->init_dyn_addr); + if (ret) + goto err_detach_dev; + + i3cdev->info.dyn_addr = i3cdev->boardinfo->init_dyn_addr; + ret = i3c_master_reattach_i3c_dev(i3cdev, 0); + if (ret) + goto err_rstdaa; + + ret = i3c_master_retrieve_dev_info(i3cdev); + if (ret) + goto err_rstdaa; + + return 0; + +err_rstdaa: + i3c_master_rstdaa_locked(master, i3cdev->boardinfo->init_dyn_addr); +err_detach_dev: + i3c_master_detach_i3c_dev(i3cdev); +err_free_dev: + i3c_master_free_i3c_dev(i3cdev); + + return ret; +} + +static void +i3c_master_register_new_i3c_devs(struct i3c_master_controller *master) +{ + struct i3c_dev_desc *desc; + int ret; + + if (!master->init_done) + return; + + i3c_bus_for_each_i3cdev(&master->bus, desc) { + if (desc->dev || !desc->info.dyn_addr || desc == master->this) + continue; + + desc->dev = kzalloc(sizeof(*desc->dev), GFP_KERNEL); + if (!desc->dev) + continue; + + desc->dev->bus = &master->bus; + desc->dev->desc = desc; + desc->dev->dev.parent = &master->dev; + desc->dev->dev.type = &i3c_device_type; + desc->dev->dev.bus = &i3c_bus_type; + desc->dev->dev.release = i3c_device_release; + dev_set_name(&desc->dev->dev, "%d-%llx", master->bus.id, + desc->info.pid); + + if (desc->boardinfo) + desc->dev->dev.of_node = desc->boardinfo->of_node; + + ret = device_register(&desc->dev->dev); + if (ret) { + dev_err(&master->dev, + "Failed to add I3C device (err = %d)\n", ret); + put_device(&desc->dev->dev); + } + } +} + +/** + * i3c_master_do_daa() - do a DAA (Dynamic Address Assignment) + * @master: master doing the DAA + * + * This function is instantiating an I3C device object and adding it to the + * I3C device list. All device information are automatically retrieved using + * standard CCC commands. + * + * The I3C device object is returned in case the master wants to attach + * private data to it using i3c_dev_set_master_data(). + * + * This function must be called with the bus lock held in write mode. + * + * Return: a 0 in case of success, an negative error code otherwise. + */ +int i3c_master_do_daa(struct i3c_master_controller *master) +{ + int ret; + + i3c_bus_maintenance_lock(&master->bus); + ret = master->ops->do_daa(master); + i3c_bus_maintenance_unlock(&master->bus); + + if (ret) + return ret; + + i3c_bus_normaluse_lock(&master->bus); + i3c_master_register_new_i3c_devs(master); + i3c_bus_normaluse_unlock(&master->bus); + + return 0; +} +EXPORT_SYMBOL_GPL(i3c_master_do_daa); + +/** + * i3c_master_set_info() - set master device information + * @master: master used to send frames on the bus + * @info: I3C device information + * + * Set master device info. This should be called from + * &i3c_master_controller_ops->bus_init(). + * + * Not all &i3c_device_info fields are meaningful for a master device. + * Here is a list of fields that should be properly filled: + * + * - &i3c_device_info->dyn_addr + * - &i3c_device_info->bcr + * - &i3c_device_info->dcr + * - &i3c_device_info->pid + * - &i3c_device_info->hdr_cap if %I3C_BCR_HDR_CAP bit is set in + * &i3c_device_info->bcr + * + * This function must be called with the bus lock held in maintenance mode. + * + * Return: 0 if @info contains valid information (not every piece of + * information can be checked, but we can at least make sure @info->dyn_addr + * and @info->bcr are correct), -EINVAL otherwise. + */ +int i3c_master_set_info(struct i3c_master_controller *master, + const struct i3c_device_info *info) +{ + struct i3c_dev_desc *i3cdev; + int ret; + + if (!i3c_bus_dev_addr_is_avail(&master->bus, info->dyn_addr)) + return -EINVAL; + + if (I3C_BCR_DEVICE_ROLE(info->bcr) == I3C_BCR_I3C_MASTER && + master->secondary) + return -EINVAL; + + if (master->this) + return -EINVAL; + + i3cdev = i3c_master_alloc_i3c_dev(master, info); + if (IS_ERR(i3cdev)) + return PTR_ERR(i3cdev); + + master->this = i3cdev; + master->bus.cur_master = master->this; + + ret = i3c_master_attach_i3c_dev(master, i3cdev); + if (ret) + goto err_free_dev; + + return 0; + +err_free_dev: + i3c_master_free_i3c_dev(i3cdev); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_set_info); + +static void i3c_master_detach_free_devs(struct i3c_master_controller *master) +{ + struct i3c_dev_desc *i3cdev, *i3ctmp; + struct i2c_dev_desc *i2cdev, *i2ctmp; + + list_for_each_entry_safe(i3cdev, i3ctmp, &master->bus.devs.i3c, + common.node) { + i3c_master_detach_i3c_dev(i3cdev); + + if (i3cdev->boardinfo && i3cdev->boardinfo->init_dyn_addr) + i3c_bus_set_addr_slot_status(&master->bus, + i3cdev->boardinfo->init_dyn_addr, + I3C_ADDR_SLOT_FREE); + + i3c_master_free_i3c_dev(i3cdev); + } + + list_for_each_entry_safe(i2cdev, i2ctmp, &master->bus.devs.i2c, + common.node) { + i3c_master_detach_i2c_dev(i2cdev); + i3c_bus_set_addr_slot_status(&master->bus, + i2cdev->addr, + I3C_ADDR_SLOT_FREE); + i3c_master_free_i2c_dev(i2cdev); + } +} + +/** + * i3c_master_bus_init() - initialize an I3C bus + * @master: main master initializing the bus + * + * This function is following all initialisation steps described in the I3C + * specification: + * + * 1. Attach I2C devs to the master so that the master can fill its internal + * device table appropriately + * + * 2. Call &i3c_master_controller_ops->bus_init() method to initialize + * the master controller. That's usually where the bus mode is selected + * (pure bus or mixed fast/slow bus) + * + * 3. Instruct all devices on the bus to drop their dynamic address. This is + * particularly important when the bus was previously configured by someone + * else (for example the bootloader) + * + * 4. Disable all slave events. + * + * 5. Reserve address slots for I3C devices with init_dyn_addr. And if devices + * also have static_addr, try to pre-assign dynamic addresses requested by + * the FW with SETDASA and attach corresponding statically defined I3C + * devices to the master. + * + * 6. Do a DAA (Dynamic Address Assignment) to assign dynamic addresses to all + * remaining I3C devices + * + * Once this is done, all I3C and I2C devices should be usable. + * + * Return: a 0 in case of success, an negative error code otherwise. + */ +static int i3c_master_bus_init(struct i3c_master_controller *master) +{ + enum i3c_addr_slot_status status; + struct i2c_dev_boardinfo *i2cboardinfo; + struct i3c_dev_boardinfo *i3cboardinfo; + struct i2c_dev_desc *i2cdev; + int ret; + + /* + * First attach all devices with static definitions provided by the + * FW. + */ + list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) { + status = i3c_bus_get_addr_slot_status(&master->bus, + i2cboardinfo->base.addr); + if (status != I3C_ADDR_SLOT_FREE) { + ret = -EBUSY; + goto err_detach_devs; + } + + i3c_bus_set_addr_slot_status(&master->bus, + i2cboardinfo->base.addr, + I3C_ADDR_SLOT_I2C_DEV); + + i2cdev = i3c_master_alloc_i2c_dev(master, + i2cboardinfo->base.addr, + i2cboardinfo->lvr); + if (IS_ERR(i2cdev)) { + ret = PTR_ERR(i2cdev); + goto err_detach_devs; + } + + ret = i3c_master_attach_i2c_dev(master, i2cdev); + if (ret) { + i3c_master_free_i2c_dev(i2cdev); + goto err_detach_devs; + } + } + + /* + * Now execute the controller specific ->bus_init() routine, which + * might configure its internal logic to match the bus limitations. + */ + ret = master->ops->bus_init(master); + if (ret) + goto err_detach_devs; + + /* + * The master device should have been instantiated in ->bus_init(), + * complain if this was not the case. + */ + if (!master->this) { + dev_err(&master->dev, + "master_set_info() was not called in ->bus_init()\n"); + ret = -EINVAL; + goto err_bus_cleanup; + } + + /* + * Reset all dynamic address that may have been assigned before + * (assigned by the bootloader for example). + */ + ret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR); + if (ret && ret != I3C_ERROR_M2) + goto err_bus_cleanup; + + /* Disable all slave events before starting DAA. */ + ret = i3c_master_disec_locked(master, I3C_BROADCAST_ADDR, + I3C_CCC_EVENT_SIR | I3C_CCC_EVENT_MR | + I3C_CCC_EVENT_HJ); + if (ret && ret != I3C_ERROR_M2) + goto err_bus_cleanup; + + /* + * Reserve init_dyn_addr first, and then try to pre-assign dynamic + * address and retrieve device information if needed. + * In case pre-assign dynamic address fails, setting dynamic address to + * the requested init_dyn_addr is retried after DAA is done in + * i3c_master_add_i3c_dev_locked(). + */ + list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) { + + /* + * We don't reserve a dynamic address for devices that + * don't explicitly request one. + */ + if (!i3cboardinfo->init_dyn_addr) + continue; + + ret = i3c_bus_get_addr_slot_status(&master->bus, + i3cboardinfo->init_dyn_addr); + if (ret != I3C_ADDR_SLOT_FREE) { + ret = -EBUSY; + goto err_rstdaa; + } + + i3c_bus_set_addr_slot_status(&master->bus, + i3cboardinfo->init_dyn_addr, + I3C_ADDR_SLOT_I3C_DEV); + + /* + * Only try to create/attach devices that have a static + * address. Other devices will be created/attached when + * DAA happens, and the requested dynamic address will + * be set using SETNEWDA once those devices become + * addressable. + */ + + if (i3cboardinfo->static_addr) + i3c_master_early_i3c_dev_add(master, i3cboardinfo); + } + + ret = i3c_master_do_daa(master); + if (ret) + goto err_rstdaa; + + return 0; + +err_rstdaa: + i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR); + +err_bus_cleanup: + if (master->ops->bus_cleanup) + master->ops->bus_cleanup(master); + +err_detach_devs: + i3c_master_detach_free_devs(master); + + return ret; +} + +static void i3c_master_bus_cleanup(struct i3c_master_controller *master) +{ + if (master->ops->bus_cleanup) + master->ops->bus_cleanup(master); + + i3c_master_detach_free_devs(master); +} + +static void i3c_master_attach_boardinfo(struct i3c_dev_desc *i3cdev) +{ + struct i3c_master_controller *master = i3cdev->common.master; + struct i3c_dev_boardinfo *i3cboardinfo; + + list_for_each_entry(i3cboardinfo, &master->boardinfo.i3c, node) { + if (i3cdev->info.pid != i3cboardinfo->pid) + continue; + + i3cdev->boardinfo = i3cboardinfo; + i3cdev->info.static_addr = i3cboardinfo->static_addr; + return; + } +} + +static struct i3c_dev_desc * +i3c_master_search_i3c_dev_duplicate(struct i3c_dev_desc *refdev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(refdev); + struct i3c_dev_desc *i3cdev; + + i3c_bus_for_each_i3cdev(&master->bus, i3cdev) { + if (i3cdev != refdev && i3cdev->info.pid == refdev->info.pid) + return i3cdev; + } + + return NULL; +} + +/** + * i3c_master_add_i3c_dev_locked() - add an I3C slave to the bus + * @master: master used to send frames on the bus + * @addr: I3C slave dynamic address assigned to the device + * + * This function is instantiating an I3C device object and adding it to the + * I3C device list. All device information are automatically retrieved using + * standard CCC commands. + * + * The I3C device object is returned in case the master wants to attach + * private data to it using i3c_dev_set_master_data(). + * + * This function must be called with the bus lock held in write mode. + * + * Return: a 0 in case of success, an negative error code otherwise. + */ +int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master, + u8 addr) +{ + struct i3c_device_info info = { .dyn_addr = addr }; + struct i3c_dev_desc *newdev, *olddev; + u8 old_dyn_addr = addr, expected_dyn_addr; + struct i3c_ibi_setup ibireq = { }; + bool enable_ibi = false; + int ret; + + if (!master) + return -EINVAL; + + newdev = i3c_master_alloc_i3c_dev(master, &info); + if (IS_ERR(newdev)) + return PTR_ERR(newdev); + + ret = i3c_master_attach_i3c_dev(master, newdev); + if (ret) + goto err_free_dev; + + ret = i3c_master_retrieve_dev_info(newdev); + if (ret) + goto err_detach_dev; + + i3c_master_attach_boardinfo(newdev); + + olddev = i3c_master_search_i3c_dev_duplicate(newdev); + if (olddev) { + newdev->dev = olddev->dev; + if (newdev->dev) + newdev->dev->desc = newdev; + + /* + * We need to restore the IBI state too, so let's save the + * IBI information and try to restore them after olddev has + * been detached+released and its IBI has been stopped and + * the associated resources have been freed. + */ + mutex_lock(&olddev->ibi_lock); + if (olddev->ibi) { + ibireq.handler = olddev->ibi->handler; + ibireq.max_payload_len = olddev->ibi->max_payload_len; + ibireq.num_slots = olddev->ibi->num_slots; + + if (olddev->ibi->enabled) { + enable_ibi = true; + i3c_dev_disable_ibi_locked(olddev); + } + + i3c_dev_free_ibi_locked(olddev); + } + mutex_unlock(&olddev->ibi_lock); + + old_dyn_addr = olddev->info.dyn_addr; + + i3c_master_detach_i3c_dev(olddev); + i3c_master_free_i3c_dev(olddev); + } + + /* + * Depending on our previous state, the expected dynamic address might + * differ: + * - if the device already had a dynamic address assigned, let's try to + * re-apply this one + * - if the device did not have a dynamic address and the firmware + * requested a specific address, pick this one + * - in any other case, keep the address automatically assigned by the + * master + */ + if (old_dyn_addr && old_dyn_addr != newdev->info.dyn_addr) + expected_dyn_addr = old_dyn_addr; + else if (newdev->boardinfo && newdev->boardinfo->init_dyn_addr) + expected_dyn_addr = newdev->boardinfo->init_dyn_addr; + else + expected_dyn_addr = newdev->info.dyn_addr; + + if (newdev->info.dyn_addr != expected_dyn_addr) { + /* + * Try to apply the expected dynamic address. If it fails, keep + * the address assigned by the master. + */ + ret = i3c_master_setnewda_locked(master, + newdev->info.dyn_addr, + expected_dyn_addr); + if (!ret) { + old_dyn_addr = newdev->info.dyn_addr; + newdev->info.dyn_addr = expected_dyn_addr; + i3c_master_reattach_i3c_dev(newdev, old_dyn_addr); + } else { + dev_err(&master->dev, + "Failed to assign reserved/old address to device %d%llx", + master->bus.id, newdev->info.pid); + } + } + + /* + * Now is time to try to restore the IBI setup. If we're lucky, + * everything works as before, otherwise, all we can do is complain. + * FIXME: maybe we should add callback to inform the driver that it + * should request the IBI again instead of trying to hide that from + * him. + */ + if (ibireq.handler) { + mutex_lock(&newdev->ibi_lock); + ret = i3c_dev_request_ibi_locked(newdev, &ibireq); + if (ret) { + dev_err(&master->dev, + "Failed to request IBI on device %d-%llx", + master->bus.id, newdev->info.pid); + } else if (enable_ibi) { + ret = i3c_dev_enable_ibi_locked(newdev); + if (ret) + dev_err(&master->dev, + "Failed to re-enable IBI on device %d-%llx", + master->bus.id, newdev->info.pid); + } + mutex_unlock(&newdev->ibi_lock); + } + + return 0; + +err_detach_dev: + if (newdev->dev && newdev->dev->desc) + newdev->dev->desc = NULL; + + i3c_master_detach_i3c_dev(newdev); + +err_free_dev: + i3c_master_free_i3c_dev(newdev); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_add_i3c_dev_locked); + +#define OF_I3C_REG1_IS_I2C_DEV BIT(31) + +static int +of_i3c_master_add_i2c_boardinfo(struct i3c_master_controller *master, + struct device_node *node, u32 *reg) +{ + struct i2c_dev_boardinfo *boardinfo; + struct device *dev = &master->dev; + int ret; + + boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL); + if (!boardinfo) + return -ENOMEM; + + ret = of_i2c_get_board_info(dev, node, &boardinfo->base); + if (ret) + return ret; + + /* + * The I3C Specification does not clearly say I2C devices with 10-bit + * address are supported. These devices can't be passed properly through + * DEFSLVS command. + */ + if (boardinfo->base.flags & I2C_CLIENT_TEN) { + dev_err(dev, "I2C device with 10 bit address not supported."); + return -ENOTSUPP; + } + + /* LVR is encoded in reg[2]. */ + boardinfo->lvr = reg[2]; + + list_add_tail(&boardinfo->node, &master->boardinfo.i2c); + of_node_get(node); + + return 0; +} + +static int +of_i3c_master_add_i3c_boardinfo(struct i3c_master_controller *master, + struct device_node *node, u32 *reg) +{ + struct i3c_dev_boardinfo *boardinfo; + struct device *dev = &master->dev; + enum i3c_addr_slot_status addrstatus; + u32 init_dyn_addr = 0; + + boardinfo = devm_kzalloc(dev, sizeof(*boardinfo), GFP_KERNEL); + if (!boardinfo) + return -ENOMEM; + + if (reg[0]) { + if (reg[0] > I3C_MAX_ADDR) + return -EINVAL; + + addrstatus = i3c_bus_get_addr_slot_status(&master->bus, + reg[0]); + if (addrstatus != I3C_ADDR_SLOT_FREE) + return -EINVAL; + } + + boardinfo->static_addr = reg[0]; + + if (!of_property_read_u32(node, "assigned-address", &init_dyn_addr)) { + if (init_dyn_addr > I3C_MAX_ADDR) + return -EINVAL; + + addrstatus = i3c_bus_get_addr_slot_status(&master->bus, + init_dyn_addr); + if (addrstatus != I3C_ADDR_SLOT_FREE) + return -EINVAL; + } + + boardinfo->pid = ((u64)reg[1] << 32) | reg[2]; + + if ((boardinfo->pid & GENMASK_ULL(63, 48)) || + I3C_PID_RND_LOWER_32BITS(boardinfo->pid)) + return -EINVAL; + + boardinfo->init_dyn_addr = init_dyn_addr; + boardinfo->of_node = of_node_get(node); + list_add_tail(&boardinfo->node, &master->boardinfo.i3c); + + return 0; +} + +static int of_i3c_master_add_dev(struct i3c_master_controller *master, + struct device_node *node) +{ + u32 reg[3]; + int ret; + + if (!master || !node) + return -EINVAL; + + ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg)); + if (ret) + return ret; + + /* + * The manufacturer ID can't be 0. If reg[1] == 0 that means we're + * dealing with an I2C device. + */ + if (!reg[1]) + ret = of_i3c_master_add_i2c_boardinfo(master, node, reg); + else + ret = of_i3c_master_add_i3c_boardinfo(master, node, reg); + + return ret; +} + +static int of_populate_i3c_bus(struct i3c_master_controller *master) +{ + struct device *dev = &master->dev; + struct device_node *i3cbus_np = dev->of_node; + struct device_node *node; + int ret; + u32 val; + + if (!i3cbus_np) + return 0; + + for_each_available_child_of_node(i3cbus_np, node) { + ret = of_i3c_master_add_dev(master, node); + if (ret) { + of_node_put(node); + return ret; + } + } + + /* + * The user might want to limit I2C and I3C speed in case some devices + * on the bus are not supporting typical rates, or if the bus topology + * prevents it from using max possible rate. + */ + if (!of_property_read_u32(i3cbus_np, "i2c-scl-hz", &val)) + master->bus.scl_rate.i2c = val; + + if (!of_property_read_u32(i3cbus_np, "i3c-scl-hz", &val)) + master->bus.scl_rate.i3c = val; + + return 0; +} + +static int i3c_master_i2c_adapter_xfer(struct i2c_adapter *adap, + struct i2c_msg *xfers, int nxfers) +{ + struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap); + struct i2c_dev_desc *dev; + int i, ret; + u16 addr; + + if (!xfers || !master || nxfers <= 0) + return -EINVAL; + + if (!master->ops->i2c_xfers) + return -ENOTSUPP; + + /* Doing transfers to different devices is not supported. */ + addr = xfers[0].addr; + for (i = 1; i < nxfers; i++) { + if (addr != xfers[i].addr) + return -ENOTSUPP; + } + + i3c_bus_normaluse_lock(&master->bus); + dev = i3c_master_find_i2c_dev_by_addr(master, addr); + if (!dev) + ret = -ENOENT; + else + ret = master->ops->i2c_xfers(dev, xfers, nxfers); + i3c_bus_normaluse_unlock(&master->bus); + + return ret ? ret : nxfers; +} + +static u32 i3c_master_i2c_funcs(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C; +} + +static u8 i3c_master_i2c_get_lvr(struct i2c_client *client) +{ + /* Fall back to no spike filters and FM bus mode. */ + u8 lvr = I3C_LVR_I2C_INDEX(2) | I3C_LVR_I2C_FM_MODE; + + if (client->dev.of_node) { + u32 reg[3]; + + if (!of_property_read_u32_array(client->dev.of_node, "reg", + reg, ARRAY_SIZE(reg))) + lvr = reg[2]; + } + + return lvr; +} + +static int i3c_master_i2c_attach(struct i2c_adapter *adap, struct i2c_client *client) +{ + struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap); + enum i3c_addr_slot_status status; + struct i2c_dev_desc *i2cdev; + int ret; + + /* Already added by board info? */ + if (i3c_master_find_i2c_dev_by_addr(master, client->addr)) + return 0; + + status = i3c_bus_get_addr_slot_status(&master->bus, client->addr); + if (status != I3C_ADDR_SLOT_FREE) + return -EBUSY; + + i3c_bus_set_addr_slot_status(&master->bus, client->addr, + I3C_ADDR_SLOT_I2C_DEV); + + i2cdev = i3c_master_alloc_i2c_dev(master, client->addr, + i3c_master_i2c_get_lvr(client)); + if (IS_ERR(i2cdev)) { + ret = PTR_ERR(i2cdev); + goto out_clear_status; + } + + ret = i3c_master_attach_i2c_dev(master, i2cdev); + if (ret) + goto out_free_dev; + + return 0; + +out_free_dev: + i3c_master_free_i2c_dev(i2cdev); +out_clear_status: + i3c_bus_set_addr_slot_status(&master->bus, client->addr, + I3C_ADDR_SLOT_FREE); + + return ret; +} + +static int i3c_master_i2c_detach(struct i2c_adapter *adap, struct i2c_client *client) +{ + struct i3c_master_controller *master = i2c_adapter_to_i3c_master(adap); + struct i2c_dev_desc *dev; + + dev = i3c_master_find_i2c_dev_by_addr(master, client->addr); + if (!dev) + return -ENODEV; + + i3c_master_detach_i2c_dev(dev); + i3c_bus_set_addr_slot_status(&master->bus, dev->addr, + I3C_ADDR_SLOT_FREE); + i3c_master_free_i2c_dev(dev); + + return 0; +} + +static const struct i2c_algorithm i3c_master_i2c_algo = { + .master_xfer = i3c_master_i2c_adapter_xfer, + .functionality = i3c_master_i2c_funcs, +}; + +static int i3c_i2c_notifier_call(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct i2c_adapter *adap; + struct i2c_client *client; + struct device *dev = data; + struct i3c_master_controller *master; + int ret; + + if (dev->type != &i2c_client_type) + return 0; + + client = to_i2c_client(dev); + adap = client->adapter; + + if (adap->algo != &i3c_master_i2c_algo) + return 0; + + master = i2c_adapter_to_i3c_master(adap); + + i3c_bus_maintenance_lock(&master->bus); + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + ret = i3c_master_i2c_attach(adap, client); + break; + case BUS_NOTIFY_DEL_DEVICE: + ret = i3c_master_i2c_detach(adap, client); + break; + } + i3c_bus_maintenance_unlock(&master->bus); + + return ret; +} + +static struct notifier_block i2cdev_notifier = { + .notifier_call = i3c_i2c_notifier_call, +}; + +static int i3c_master_i2c_adapter_init(struct i3c_master_controller *master) +{ + struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master); + struct i2c_dev_desc *i2cdev; + struct i2c_dev_boardinfo *i2cboardinfo; + int ret; + + adap->dev.parent = master->dev.parent; + adap->owner = master->dev.parent->driver->owner; + adap->algo = &i3c_master_i2c_algo; + strncpy(adap->name, dev_name(master->dev.parent), sizeof(adap->name)); + + /* FIXME: Should we allow i3c masters to override these values? */ + adap->timeout = 1000; + adap->retries = 3; + + ret = i2c_add_adapter(adap); + if (ret) + return ret; + + /* + * We silently ignore failures here. The bus should keep working + * correctly even if one or more i2c devices are not registered. + */ + list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) { + i2cdev = i3c_master_find_i2c_dev_by_addr(master, + i2cboardinfo->base.addr); + if (WARN_ON(!i2cdev)) + continue; + i2cdev->dev = i2c_new_client_device(adap, &i2cboardinfo->base); + } + + return 0; +} + +static void i3c_master_i2c_adapter_cleanup(struct i3c_master_controller *master) +{ + struct i2c_dev_desc *i2cdev; + + i2c_del_adapter(&master->i2c); + + i3c_bus_for_each_i2cdev(&master->bus, i2cdev) + i2cdev->dev = NULL; +} + +static void i3c_master_unregister_i3c_devs(struct i3c_master_controller *master) +{ + struct i3c_dev_desc *i3cdev; + + i3c_bus_for_each_i3cdev(&master->bus, i3cdev) { + if (!i3cdev->dev) + continue; + + i3cdev->dev->desc = NULL; + if (device_is_registered(&i3cdev->dev->dev)) + device_unregister(&i3cdev->dev->dev); + else + put_device(&i3cdev->dev->dev); + i3cdev->dev = NULL; + } +} + +/** + * i3c_master_queue_ibi() - Queue an IBI + * @dev: the device this IBI is coming from + * @slot: the IBI slot used to store the payload + * + * Queue an IBI to the controller workqueue. The IBI handler attached to + * the dev will be called from a workqueue context. + */ +void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot) +{ + atomic_inc(&dev->ibi->pending_ibis); + queue_work(dev->common.master->wq, &slot->work); +} +EXPORT_SYMBOL_GPL(i3c_master_queue_ibi); + +static void i3c_master_handle_ibi(struct work_struct *work) +{ + struct i3c_ibi_slot *slot = container_of(work, struct i3c_ibi_slot, + work); + struct i3c_dev_desc *dev = slot->dev; + struct i3c_master_controller *master = i3c_dev_get_master(dev); + struct i3c_ibi_payload payload; + + payload.data = slot->data; + payload.len = slot->len; + + if (dev->dev) + dev->ibi->handler(dev->dev, &payload); + + master->ops->recycle_ibi_slot(dev, slot); + if (atomic_dec_and_test(&dev->ibi->pending_ibis)) + complete(&dev->ibi->all_ibis_handled); +} + +static void i3c_master_init_ibi_slot(struct i3c_dev_desc *dev, + struct i3c_ibi_slot *slot) +{ + slot->dev = dev; + INIT_WORK(&slot->work, i3c_master_handle_ibi); +} + +struct i3c_generic_ibi_slot { + struct list_head node; + struct i3c_ibi_slot base; +}; + +struct i3c_generic_ibi_pool { + spinlock_t lock; + unsigned int num_slots; + struct i3c_generic_ibi_slot *slots; + void *payload_buf; + struct list_head free_slots; + struct list_head pending; +}; + +/** + * i3c_generic_ibi_free_pool() - Free a generic IBI pool + * @pool: the IBI pool to free + * + * Free all IBI slots allated by a generic IBI pool. + */ +void i3c_generic_ibi_free_pool(struct i3c_generic_ibi_pool *pool) +{ + struct i3c_generic_ibi_slot *slot; + unsigned int nslots = 0; + + while (!list_empty(&pool->free_slots)) { + slot = list_first_entry(&pool->free_slots, + struct i3c_generic_ibi_slot, node); + list_del(&slot->node); + nslots++; + } + + /* + * If the number of freed slots is not equal to the number of allocated + * slots we have a leak somewhere. + */ + WARN_ON(nslots != pool->num_slots); + + kfree(pool->payload_buf); + kfree(pool->slots); + kfree(pool); +} +EXPORT_SYMBOL_GPL(i3c_generic_ibi_free_pool); + +/** + * i3c_generic_ibi_alloc_pool() - Create a generic IBI pool + * @dev: the device this pool will be used for + * @req: IBI setup request describing what the device driver expects + * + * Create a generic IBI pool based on the information provided in @req. + * + * Return: a valid IBI pool in case of success, an ERR_PTR() otherwise. + */ +struct i3c_generic_ibi_pool * +i3c_generic_ibi_alloc_pool(struct i3c_dev_desc *dev, + const struct i3c_ibi_setup *req) +{ + struct i3c_generic_ibi_pool *pool; + struct i3c_generic_ibi_slot *slot; + unsigned int i; + int ret; + + pool = kzalloc(sizeof(*pool), GFP_KERNEL); + if (!pool) + return ERR_PTR(-ENOMEM); + + spin_lock_init(&pool->lock); + INIT_LIST_HEAD(&pool->free_slots); + INIT_LIST_HEAD(&pool->pending); + + pool->slots = kcalloc(req->num_slots, sizeof(*slot), GFP_KERNEL); + if (!pool->slots) { + ret = -ENOMEM; + goto err_free_pool; + } + + if (req->max_payload_len) { + pool->payload_buf = kcalloc(req->num_slots, + req->max_payload_len, GFP_KERNEL); + if (!pool->payload_buf) { + ret = -ENOMEM; + goto err_free_pool; + } + } + + for (i = 0; i < req->num_slots; i++) { + slot = &pool->slots[i]; + i3c_master_init_ibi_slot(dev, &slot->base); + + if (req->max_payload_len) + slot->base.data = pool->payload_buf + + (i * req->max_payload_len); + + list_add_tail(&slot->node, &pool->free_slots); + pool->num_slots++; + } + + return pool; + +err_free_pool: + i3c_generic_ibi_free_pool(pool); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(i3c_generic_ibi_alloc_pool); + +/** + * i3c_generic_ibi_get_free_slot() - Get a free slot from a generic IBI pool + * @pool: the pool to query an IBI slot on + * + * Search for a free slot in a generic IBI pool. + * The slot should be returned to the pool using i3c_generic_ibi_recycle_slot() + * when it's no longer needed. + * + * Return: a pointer to a free slot, or NULL if there's no free slot available. + */ +struct i3c_ibi_slot * +i3c_generic_ibi_get_free_slot(struct i3c_generic_ibi_pool *pool) +{ + struct i3c_generic_ibi_slot *slot; + unsigned long flags; + + spin_lock_irqsave(&pool->lock, flags); + slot = list_first_entry_or_null(&pool->free_slots, + struct i3c_generic_ibi_slot, node); + if (slot) + list_del(&slot->node); + spin_unlock_irqrestore(&pool->lock, flags); + + return slot ? &slot->base : NULL; +} +EXPORT_SYMBOL_GPL(i3c_generic_ibi_get_free_slot); + +/** + * i3c_generic_ibi_recycle_slot() - Return a slot to a generic IBI pool + * @pool: the pool to return the IBI slot to + * @s: IBI slot to recycle + * + * Add an IBI slot back to its generic IBI pool. Should be called from the + * master driver struct_master_controller_ops->recycle_ibi() method. + */ +void i3c_generic_ibi_recycle_slot(struct i3c_generic_ibi_pool *pool, + struct i3c_ibi_slot *s) +{ + struct i3c_generic_ibi_slot *slot; + unsigned long flags; + + if (!s) + return; + + slot = container_of(s, struct i3c_generic_ibi_slot, base); + spin_lock_irqsave(&pool->lock, flags); + list_add_tail(&slot->node, &pool->free_slots); + spin_unlock_irqrestore(&pool->lock, flags); +} +EXPORT_SYMBOL_GPL(i3c_generic_ibi_recycle_slot); + +static int i3c_master_check_ops(const struct i3c_master_controller_ops *ops) +{ + if (!ops || !ops->bus_init || !ops->priv_xfers || + !ops->send_ccc_cmd || !ops->do_daa || !ops->i2c_xfers) + return -EINVAL; + + if (ops->request_ibi && + (!ops->enable_ibi || !ops->disable_ibi || !ops->free_ibi || + !ops->recycle_ibi_slot)) + return -EINVAL; + + return 0; +} + +/** + * i3c_master_register() - register an I3C master + * @master: master used to send frames on the bus + * @parent: the parent device (the one that provides this I3C master + * controller) + * @ops: the master controller operations + * @secondary: true if you are registering a secondary master. Will return + * -ENOTSUPP if set to true since secondary masters are not yet + * supported + * + * This function takes care of everything for you: + * + * - creates and initializes the I3C bus + * - populates the bus with static I2C devs if @parent->of_node is not + * NULL + * - registers all I3C devices added by the controller during bus + * initialization + * - registers the I2C adapter and all I2C devices + * + * Return: 0 in case of success, a negative error code otherwise. + */ +int i3c_master_register(struct i3c_master_controller *master, + struct device *parent, + const struct i3c_master_controller_ops *ops, + bool secondary) +{ + unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE; + struct i3c_bus *i3cbus = i3c_master_get_bus(master); + enum i3c_bus_mode mode = I3C_BUS_MODE_PURE; + struct i2c_dev_boardinfo *i2cbi; + int ret; + + /* We do not support secondary masters yet. */ + if (secondary) + return -ENOTSUPP; + + ret = i3c_master_check_ops(ops); + if (ret) + return ret; + + master->dev.parent = parent; + master->dev.of_node = of_node_get(parent->of_node); + master->dev.bus = &i3c_bus_type; + master->dev.type = &i3c_masterdev_type; + master->dev.release = i3c_masterdev_release; + master->ops = ops; + master->secondary = secondary; + INIT_LIST_HEAD(&master->boardinfo.i2c); + INIT_LIST_HEAD(&master->boardinfo.i3c); + + ret = i3c_bus_init(i3cbus); + if (ret) + return ret; + + device_initialize(&master->dev); + dev_set_name(&master->dev, "i3c-%d", i3cbus->id); + + ret = of_populate_i3c_bus(master); + if (ret) + goto err_put_dev; + + list_for_each_entry(i2cbi, &master->boardinfo.i2c, node) { + switch (i2cbi->lvr & I3C_LVR_I2C_INDEX_MASK) { + case I3C_LVR_I2C_INDEX(0): + if (mode < I3C_BUS_MODE_MIXED_FAST) + mode = I3C_BUS_MODE_MIXED_FAST; + break; + case I3C_LVR_I2C_INDEX(1): + if (mode < I3C_BUS_MODE_MIXED_LIMITED) + mode = I3C_BUS_MODE_MIXED_LIMITED; + break; + case I3C_LVR_I2C_INDEX(2): + if (mode < I3C_BUS_MODE_MIXED_SLOW) + mode = I3C_BUS_MODE_MIXED_SLOW; + break; + default: + ret = -EINVAL; + goto err_put_dev; + } + + if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE) + i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE; + } + + ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate); + if (ret) + goto err_put_dev; + + master->wq = alloc_workqueue("%s", 0, 0, dev_name(parent)); + if (!master->wq) { + ret = -ENOMEM; + goto err_put_dev; + } + + ret = i3c_master_bus_init(master); + if (ret) + goto err_put_dev; + + ret = device_add(&master->dev); + if (ret) + goto err_cleanup_bus; + + /* + * Expose our I3C bus as an I2C adapter so that I2C devices are exposed + * through the I2C subsystem. + */ + ret = i3c_master_i2c_adapter_init(master); + if (ret) + goto err_del_dev; + + /* + * We're done initializing the bus and the controller, we can now + * register I3C devices discovered during the initial DAA. + */ + master->init_done = true; + i3c_bus_normaluse_lock(&master->bus); + i3c_master_register_new_i3c_devs(master); + i3c_bus_normaluse_unlock(&master->bus); + + return 0; + +err_del_dev: + device_del(&master->dev); + +err_cleanup_bus: + i3c_master_bus_cleanup(master); + +err_put_dev: + put_device(&master->dev); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_register); + +/** + * i3c_master_unregister() - unregister an I3C master + * @master: master used to send frames on the bus + * + * Basically undo everything done in i3c_master_register(). + * + * Return: 0 in case of success, a negative error code otherwise. + */ +int i3c_master_unregister(struct i3c_master_controller *master) +{ + i3c_master_i2c_adapter_cleanup(master); + i3c_master_unregister_i3c_devs(master); + i3c_master_bus_cleanup(master); + device_unregister(&master->dev); + + return 0; +} +EXPORT_SYMBOL_GPL(i3c_master_unregister); + +int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev, + struct i3c_priv_xfer *xfers, + int nxfers) +{ + struct i3c_master_controller *master; + + if (!dev) + return -ENOENT; + + master = i3c_dev_get_master(dev); + if (!master || !xfers) + return -EINVAL; + + if (!master->ops->priv_xfers) + return -ENOTSUPP; + + return master->ops->priv_xfers(dev, xfers, nxfers); +} + +int i3c_dev_disable_ibi_locked(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master; + int ret; + + if (!dev->ibi) + return -EINVAL; + + master = i3c_dev_get_master(dev); + ret = master->ops->disable_ibi(dev); + if (ret) + return ret; + + reinit_completion(&dev->ibi->all_ibis_handled); + if (atomic_read(&dev->ibi->pending_ibis)) + wait_for_completion(&dev->ibi->all_ibis_handled); + + dev->ibi->enabled = false; + + return 0; +} + +int i3c_dev_enable_ibi_locked(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + int ret; + + if (!dev->ibi) + return -EINVAL; + + ret = master->ops->enable_ibi(dev); + if (!ret) + dev->ibi->enabled = true; + + return ret; +} + +int i3c_dev_request_ibi_locked(struct i3c_dev_desc *dev, + const struct i3c_ibi_setup *req) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + struct i3c_device_ibi_info *ibi; + int ret; + + if (!master->ops->request_ibi) + return -ENOTSUPP; + + if (dev->ibi) + return -EBUSY; + + ibi = kzalloc(sizeof(*ibi), GFP_KERNEL); + if (!ibi) + return -ENOMEM; + + atomic_set(&ibi->pending_ibis, 0); + init_completion(&ibi->all_ibis_handled); + ibi->handler = req->handler; + ibi->max_payload_len = req->max_payload_len; + ibi->num_slots = req->num_slots; + + dev->ibi = ibi; + ret = master->ops->request_ibi(dev, req); + if (ret) { + kfree(ibi); + dev->ibi = NULL; + } + + return ret; +} + +void i3c_dev_free_ibi_locked(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master = i3c_dev_get_master(dev); + + if (!dev->ibi) + return; + + if (WARN_ON(dev->ibi->enabled)) + WARN_ON(i3c_dev_disable_ibi_locked(dev)); + + master->ops->free_ibi(dev); + kfree(dev->ibi); + dev->ibi = NULL; +} + +static int __init i3c_init(void) +{ + int res = bus_register_notifier(&i2c_bus_type, &i2cdev_notifier); + + if (res) + return res; + + res = bus_register(&i3c_bus_type); + if (res) + goto out_unreg_notifier; + + return 0; + +out_unreg_notifier: + bus_unregister_notifier(&i2c_bus_type, &i2cdev_notifier); + + return res; +} +subsys_initcall(i3c_init); + +static void __exit i3c_exit(void) +{ + bus_unregister_notifier(&i2c_bus_type, &i2cdev_notifier); + idr_destroy(&i3c_bus_idr); + bus_unregister(&i3c_bus_type); +} +module_exit(i3c_exit); + +MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>"); +MODULE_DESCRIPTION("I3C core"); +MODULE_LICENSE("GPL v2"); |