diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/soundwire/bus.c | 1967 |
1 files changed, 1967 insertions, 0 deletions
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c new file mode 100644 index 000000000..f7b3e6a69 --- /dev/null +++ b/drivers/soundwire/bus.c @@ -0,0 +1,1967 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2015-17 Intel Corporation. + +#include <linux/acpi.h> +#include <linux/delay.h> +#include <linux/mod_devicetable.h> +#include <linux/pm_runtime.h> +#include <linux/soundwire/sdw_registers.h> +#include <linux/soundwire/sdw.h> +#include <linux/soundwire/sdw_type.h> +#include "bus.h" +#include "sysfs_local.h" + +static DEFINE_IDA(sdw_bus_ida); +static DEFINE_IDA(sdw_peripheral_ida); + +static int sdw_get_id(struct sdw_bus *bus) +{ + int rc = ida_alloc(&sdw_bus_ida, GFP_KERNEL); + + if (rc < 0) + return rc; + + bus->id = rc; + return 0; +} + +/** + * sdw_bus_master_add() - add a bus Master instance + * @bus: bus instance + * @parent: parent device + * @fwnode: firmware node handle + * + * Initializes the bus instance, read properties and create child + * devices. + */ +int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent, + struct fwnode_handle *fwnode) +{ + struct sdw_master_prop *prop = NULL; + int ret; + + if (!parent) { + pr_err("SoundWire parent device is not set\n"); + return -ENODEV; + } + + ret = sdw_get_id(bus); + if (ret < 0) { + dev_err(parent, "Failed to get bus id\n"); + return ret; + } + + ret = sdw_master_device_add(bus, parent, fwnode); + if (ret < 0) { + dev_err(parent, "Failed to add master device at link %d\n", + bus->link_id); + return ret; + } + + if (!bus->ops) { + dev_err(bus->dev, "SoundWire Bus ops are not set\n"); + return -EINVAL; + } + + if (!bus->compute_params) { + dev_err(bus->dev, + "Bandwidth allocation not configured, compute_params no set\n"); + return -EINVAL; + } + + mutex_init(&bus->msg_lock); + mutex_init(&bus->bus_lock); + INIT_LIST_HEAD(&bus->slaves); + INIT_LIST_HEAD(&bus->m_rt_list); + + /* + * Initialize multi_link flag + */ + bus->multi_link = false; + if (bus->ops->read_prop) { + ret = bus->ops->read_prop(bus); + if (ret < 0) { + dev_err(bus->dev, + "Bus read properties failed:%d\n", ret); + return ret; + } + } + + sdw_bus_debugfs_init(bus); + + /* + * Device numbers in SoundWire are 0 through 15. Enumeration device + * number (0), Broadcast device number (15), Group numbers (12 and + * 13) and Master device number (14) are not used for assignment so + * mask these and other higher bits. + */ + + /* Set higher order bits */ + *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM); + + /* Set enumuration device number and broadcast device number */ + set_bit(SDW_ENUM_DEV_NUM, bus->assigned); + set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned); + + /* Set group device numbers and master device number */ + set_bit(SDW_GROUP12_DEV_NUM, bus->assigned); + set_bit(SDW_GROUP13_DEV_NUM, bus->assigned); + set_bit(SDW_MASTER_DEV_NUM, bus->assigned); + + /* + * SDW is an enumerable bus, but devices can be powered off. So, + * they won't be able to report as present. + * + * Create Slave devices based on Slaves described in + * the respective firmware (ACPI/DT) + */ + if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev)) + ret = sdw_acpi_find_slaves(bus); + else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node) + ret = sdw_of_find_slaves(bus); + else + ret = -ENOTSUPP; /* No ACPI/DT so error out */ + + if (ret < 0) { + dev_err(bus->dev, "Finding slaves failed:%d\n", ret); + return ret; + } + + /* + * Initialize clock values based on Master properties. The max + * frequency is read from max_clk_freq property. Current assumption + * is that the bus will start at highest clock frequency when + * powered on. + * + * Default active bank will be 0 as out of reset the Slaves have + * to start with bank 0 (Table 40 of Spec) + */ + prop = &bus->prop; + bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR; + bus->params.curr_dr_freq = bus->params.max_dr_freq; + bus->params.curr_bank = SDW_BANK0; + bus->params.next_bank = SDW_BANK1; + + return 0; +} +EXPORT_SYMBOL(sdw_bus_master_add); + +static int sdw_delete_slave(struct device *dev, void *data) +{ + struct sdw_slave *slave = dev_to_sdw_dev(dev); + struct sdw_bus *bus = slave->bus; + + pm_runtime_disable(dev); + + sdw_slave_debugfs_exit(slave); + + mutex_lock(&bus->bus_lock); + + if (slave->dev_num) { /* clear dev_num if assigned */ + clear_bit(slave->dev_num, bus->assigned); + if (bus->dev_num_ida_min) + ida_free(&sdw_peripheral_ida, slave->dev_num); + } + list_del_init(&slave->node); + mutex_unlock(&bus->bus_lock); + + device_unregister(dev); + return 0; +} + +/** + * sdw_bus_master_delete() - delete the bus master instance + * @bus: bus to be deleted + * + * Remove the instance, delete the child devices. + */ +void sdw_bus_master_delete(struct sdw_bus *bus) +{ + device_for_each_child(bus->dev, NULL, sdw_delete_slave); + sdw_master_device_del(bus); + + sdw_bus_debugfs_exit(bus); + ida_free(&sdw_bus_ida, bus->id); +} +EXPORT_SYMBOL(sdw_bus_master_delete); + +/* + * SDW IO Calls + */ + +static inline int find_response_code(enum sdw_command_response resp) +{ + switch (resp) { + case SDW_CMD_OK: + return 0; + + case SDW_CMD_IGNORED: + return -ENODATA; + + case SDW_CMD_TIMEOUT: + return -ETIMEDOUT; + + default: + return -EIO; + } +} + +static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg) +{ + int retry = bus->prop.err_threshold; + enum sdw_command_response resp; + int ret = 0, i; + + for (i = 0; i <= retry; i++) { + resp = bus->ops->xfer_msg(bus, msg); + ret = find_response_code(resp); + + /* if cmd is ok or ignored return */ + if (ret == 0 || ret == -ENODATA) + return ret; + } + + return ret; +} + +static inline int do_transfer_defer(struct sdw_bus *bus, + struct sdw_msg *msg, + struct sdw_defer *defer) +{ + int retry = bus->prop.err_threshold; + enum sdw_command_response resp; + int ret = 0, i; + + defer->msg = msg; + defer->length = msg->len; + init_completion(&defer->complete); + + for (i = 0; i <= retry; i++) { + resp = bus->ops->xfer_msg_defer(bus, msg, defer); + ret = find_response_code(resp); + /* if cmd is ok or ignored return */ + if (ret == 0 || ret == -ENODATA) + return ret; + } + + return ret; +} + +static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num) +{ + int retry = bus->prop.err_threshold; + enum sdw_command_response resp; + int ret = 0, i; + + for (i = 0; i <= retry; i++) { + resp = bus->ops->reset_page_addr(bus, dev_num); + ret = find_response_code(resp); + /* if cmd is ok or ignored return */ + if (ret == 0 || ret == -ENODATA) + return ret; + } + + return ret; +} + +static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg) +{ + int ret; + + ret = do_transfer(bus, msg); + if (ret != 0 && ret != -ENODATA) + dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n", + msg->dev_num, ret, + (msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read", + msg->addr, msg->len); + + if (msg->page) + sdw_reset_page(bus, msg->dev_num); + + return ret; +} + +/** + * sdw_transfer() - Synchronous transfer message to a SDW Slave device + * @bus: SDW bus + * @msg: SDW message to be xfered + */ +int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg) +{ + int ret; + + mutex_lock(&bus->msg_lock); + + ret = sdw_transfer_unlocked(bus, msg); + + mutex_unlock(&bus->msg_lock); + + return ret; +} + +/** + * sdw_show_ping_status() - Direct report of PING status, to be used by Peripheral drivers + * @bus: SDW bus + * @sync_delay: Delay before reading status + */ +void sdw_show_ping_status(struct sdw_bus *bus, bool sync_delay) +{ + u32 status; + + if (!bus->ops->read_ping_status) + return; + + /* + * wait for peripheral to sync if desired. 10-15ms should be more than + * enough in most cases. + */ + if (sync_delay) + usleep_range(10000, 15000); + + mutex_lock(&bus->msg_lock); + + status = bus->ops->read_ping_status(bus); + + mutex_unlock(&bus->msg_lock); + + if (!status) + dev_warn(bus->dev, "%s: no peripherals attached\n", __func__); + else + dev_dbg(bus->dev, "PING status: %#x\n", status); +} +EXPORT_SYMBOL(sdw_show_ping_status); + +/** + * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device + * @bus: SDW bus + * @msg: SDW message to be xfered + * @defer: Defer block for signal completion + * + * Caller needs to hold the msg_lock lock while calling this + */ +int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg, + struct sdw_defer *defer) +{ + int ret; + + if (!bus->ops->xfer_msg_defer) + return -ENOTSUPP; + + ret = do_transfer_defer(bus, msg, defer); + if (ret != 0 && ret != -ENODATA) + dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n", + msg->dev_num, ret); + + if (msg->page) + sdw_reset_page(bus, msg->dev_num); + + return ret; +} + +int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave, + u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf) +{ + memset(msg, 0, sizeof(*msg)); + msg->addr = addr; /* addr is 16 bit and truncated here */ + msg->len = count; + msg->dev_num = dev_num; + msg->flags = flags; + msg->buf = buf; + + if (addr < SDW_REG_NO_PAGE) /* no paging area */ + return 0; + + if (addr >= SDW_REG_MAX) { /* illegal addr */ + pr_err("SDW: Invalid address %x passed\n", addr); + return -EINVAL; + } + + if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */ + if (slave && !slave->prop.paging_support) + return 0; + /* no need for else as that will fall-through to paging */ + } + + /* paging mandatory */ + if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) { + pr_err("SDW: Invalid device for paging :%d\n", dev_num); + return -EINVAL; + } + + if (!slave) { + pr_err("SDW: No slave for paging addr\n"); + return -EINVAL; + } + + if (!slave->prop.paging_support) { + dev_err(&slave->dev, + "address %x needs paging but no support\n", addr); + return -EINVAL; + } + + msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr); + msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr); + msg->addr |= BIT(15); + msg->page = true; + + return 0; +} + +/* + * Read/Write IO functions. + * no_pm versions can only be called by the bus, e.g. while enumerating or + * handling suspend-resume sequences. + * all clients need to use the pm versions + */ + +static int +sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) +{ + struct sdw_msg msg; + int ret; + + ret = sdw_fill_msg(&msg, slave, addr, count, + slave->dev_num, SDW_MSG_FLAG_READ, val); + if (ret < 0) + return ret; + + ret = sdw_transfer(slave->bus, &msg); + if (slave->is_mockup_device) + ret = 0; + return ret; +} + +static int +sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val) +{ + struct sdw_msg msg; + int ret; + + ret = sdw_fill_msg(&msg, slave, addr, count, + slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val); + if (ret < 0) + return ret; + + ret = sdw_transfer(slave->bus, &msg); + if (slave->is_mockup_device) + ret = 0; + return ret; +} + +int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value) +{ + return sdw_nwrite_no_pm(slave, addr, 1, &value); +} +EXPORT_SYMBOL(sdw_write_no_pm); + +static int +sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr) +{ + struct sdw_msg msg; + u8 buf; + int ret; + + ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num, + SDW_MSG_FLAG_READ, &buf); + if (ret < 0) + return ret; + + ret = sdw_transfer(bus, &msg); + if (ret < 0) + return ret; + + return buf; +} + +static int +sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value) +{ + struct sdw_msg msg; + int ret; + + ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num, + SDW_MSG_FLAG_WRITE, &value); + if (ret < 0) + return ret; + + return sdw_transfer(bus, &msg); +} + +int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr) +{ + struct sdw_msg msg; + u8 buf; + int ret; + + ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num, + SDW_MSG_FLAG_READ, &buf); + if (ret < 0) + return ret; + + ret = sdw_transfer_unlocked(bus, &msg); + if (ret < 0) + return ret; + + return buf; +} +EXPORT_SYMBOL(sdw_bread_no_pm_unlocked); + +int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value) +{ + struct sdw_msg msg; + int ret; + + ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num, + SDW_MSG_FLAG_WRITE, &value); + if (ret < 0) + return ret; + + return sdw_transfer_unlocked(bus, &msg); +} +EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked); + +int sdw_read_no_pm(struct sdw_slave *slave, u32 addr) +{ + u8 buf; + int ret; + + ret = sdw_nread_no_pm(slave, addr, 1, &buf); + if (ret < 0) + return ret; + else + return buf; +} +EXPORT_SYMBOL(sdw_read_no_pm); + +int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val) +{ + int tmp; + + tmp = sdw_read_no_pm(slave, addr); + if (tmp < 0) + return tmp; + + tmp = (tmp & ~mask) | val; + return sdw_write_no_pm(slave, addr, tmp); +} +EXPORT_SYMBOL(sdw_update_no_pm); + +/* Read-Modify-Write Slave register */ +int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val) +{ + int tmp; + + tmp = sdw_read(slave, addr); + if (tmp < 0) + return tmp; + + tmp = (tmp & ~mask) | val; + return sdw_write(slave, addr, tmp); +} +EXPORT_SYMBOL(sdw_update); + +/** + * sdw_nread() - Read "n" contiguous SDW Slave registers + * @slave: SDW Slave + * @addr: Register address + * @count: length + * @val: Buffer for values to be read + */ +int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) +{ + int ret; + + ret = pm_runtime_get_sync(&slave->dev); + if (ret < 0 && ret != -EACCES) { + pm_runtime_put_noidle(&slave->dev); + return ret; + } + + ret = sdw_nread_no_pm(slave, addr, count, val); + + pm_runtime_mark_last_busy(&slave->dev); + pm_runtime_put(&slave->dev); + + return ret; +} +EXPORT_SYMBOL(sdw_nread); + +/** + * sdw_nwrite() - Write "n" contiguous SDW Slave registers + * @slave: SDW Slave + * @addr: Register address + * @count: length + * @val: Buffer for values to be written + */ +int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val) +{ + int ret; + + ret = pm_runtime_get_sync(&slave->dev); + if (ret < 0 && ret != -EACCES) { + pm_runtime_put_noidle(&slave->dev); + return ret; + } + + ret = sdw_nwrite_no_pm(slave, addr, count, val); + + pm_runtime_mark_last_busy(&slave->dev); + pm_runtime_put(&slave->dev); + + return ret; +} +EXPORT_SYMBOL(sdw_nwrite); + +/** + * sdw_read() - Read a SDW Slave register + * @slave: SDW Slave + * @addr: Register address + */ +int sdw_read(struct sdw_slave *slave, u32 addr) +{ + u8 buf; + int ret; + + ret = sdw_nread(slave, addr, 1, &buf); + if (ret < 0) + return ret; + + return buf; +} +EXPORT_SYMBOL(sdw_read); + +/** + * sdw_write() - Write a SDW Slave register + * @slave: SDW Slave + * @addr: Register address + * @value: Register value + */ +int sdw_write(struct sdw_slave *slave, u32 addr, u8 value) +{ + return sdw_nwrite(slave, addr, 1, &value); +} +EXPORT_SYMBOL(sdw_write); + +/* + * SDW alert handling + */ + +/* called with bus_lock held */ +static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i) +{ + struct sdw_slave *slave; + + list_for_each_entry(slave, &bus->slaves, node) { + if (slave->dev_num == i) + return slave; + } + + return NULL; +} + +int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id) +{ + if (slave->id.mfg_id != id.mfg_id || + slave->id.part_id != id.part_id || + slave->id.class_id != id.class_id || + (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID && + slave->id.unique_id != id.unique_id)) + return -ENODEV; + + return 0; +} +EXPORT_SYMBOL(sdw_compare_devid); + +/* called with bus_lock held */ +static int sdw_get_device_num(struct sdw_slave *slave) +{ + int bit; + + if (slave->bus->dev_num_ida_min) { + bit = ida_alloc_range(&sdw_peripheral_ida, + slave->bus->dev_num_ida_min, SDW_MAX_DEVICES, + GFP_KERNEL); + if (bit < 0) + goto err; + } else { + bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES); + if (bit == SDW_MAX_DEVICES) { + bit = -ENODEV; + goto err; + } + } + + /* + * Do not update dev_num in Slave data structure here, + * Update once program dev_num is successful + */ + set_bit(bit, slave->bus->assigned); + +err: + return bit; +} + +static int sdw_assign_device_num(struct sdw_slave *slave) +{ + struct sdw_bus *bus = slave->bus; + int ret, dev_num; + bool new_device = false; + + /* check first if device number is assigned, if so reuse that */ + if (!slave->dev_num) { + if (!slave->dev_num_sticky) { + mutex_lock(&slave->bus->bus_lock); + dev_num = sdw_get_device_num(slave); + mutex_unlock(&slave->bus->bus_lock); + if (dev_num < 0) { + dev_err(bus->dev, "Get dev_num failed: %d\n", + dev_num); + return dev_num; + } + slave->dev_num = dev_num; + slave->dev_num_sticky = dev_num; + new_device = true; + } else { + slave->dev_num = slave->dev_num_sticky; + } + } + + if (!new_device) + dev_dbg(bus->dev, + "Slave already registered, reusing dev_num:%d\n", + slave->dev_num); + + /* Clear the slave->dev_num to transfer message on device 0 */ + dev_num = slave->dev_num; + slave->dev_num = 0; + + ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num); + if (ret < 0) { + dev_err(bus->dev, "Program device_num %d failed: %d\n", + dev_num, ret); + return ret; + } + + /* After xfer of msg, restore dev_num */ + slave->dev_num = slave->dev_num_sticky; + + return 0; +} + +void sdw_extract_slave_id(struct sdw_bus *bus, + u64 addr, struct sdw_slave_id *id) +{ + dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr); + + id->sdw_version = SDW_VERSION(addr); + id->unique_id = SDW_UNIQUE_ID(addr); + id->mfg_id = SDW_MFG_ID(addr); + id->part_id = SDW_PART_ID(addr); + id->class_id = SDW_CLASS_ID(addr); + + dev_dbg(bus->dev, + "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n", + id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version); +} +EXPORT_SYMBOL(sdw_extract_slave_id); + +static int sdw_program_device_num(struct sdw_bus *bus, bool *programmed) +{ + u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0}; + struct sdw_slave *slave, *_s; + struct sdw_slave_id id; + struct sdw_msg msg; + bool found; + int count = 0, ret; + u64 addr; + + *programmed = false; + + /* No Slave, so use raw xfer api */ + ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0, + SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf); + if (ret < 0) + return ret; + + do { + ret = sdw_transfer(bus, &msg); + if (ret == -ENODATA) { /* end of device id reads */ + dev_dbg(bus->dev, "No more devices to enumerate\n"); + ret = 0; + break; + } + if (ret < 0) { + dev_err(bus->dev, "DEVID read fail:%d\n", ret); + break; + } + + /* + * Construct the addr and extract. Cast the higher shift + * bits to avoid truncation due to size limit. + */ + addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) | + ((u64)buf[2] << 24) | ((u64)buf[1] << 32) | + ((u64)buf[0] << 40); + + sdw_extract_slave_id(bus, addr, &id); + + found = false; + /* Now compare with entries */ + list_for_each_entry_safe(slave, _s, &bus->slaves, node) { + if (sdw_compare_devid(slave, id) == 0) { + found = true; + + /* + * To prevent skipping state-machine stages don't + * program a device until we've seen it UNATTACH. + * Must return here because no other device on #0 + * can be detected until this one has been + * assigned a device ID. + */ + if (slave->status != SDW_SLAVE_UNATTACHED) + return 0; + + /* + * Assign a new dev_num to this Slave and + * not mark it present. It will be marked + * present after it reports ATTACHED on new + * dev_num + */ + ret = sdw_assign_device_num(slave); + if (ret < 0) { + dev_err(bus->dev, + "Assign dev_num failed:%d\n", + ret); + return ret; + } + + *programmed = true; + + break; + } + } + + if (!found) { + /* TODO: Park this device in Group 13 */ + + /* + * add Slave device even if there is no platform + * firmware description. There will be no driver probe + * but the user/integration will be able to see the + * device, enumeration status and device number in sysfs + */ + sdw_slave_add(bus, &id, NULL); + + dev_err(bus->dev, "Slave Entry not found\n"); + } + + count++; + + /* + * Check till error out or retry (count) exhausts. + * Device can drop off and rejoin during enumeration + * so count till twice the bound. + */ + + } while (ret == 0 && count < (SDW_MAX_DEVICES * 2)); + + return ret; +} + +static void sdw_modify_slave_status(struct sdw_slave *slave, + enum sdw_slave_status status) +{ + struct sdw_bus *bus = slave->bus; + + mutex_lock(&bus->bus_lock); + + dev_vdbg(bus->dev, + "changing status slave %d status %d new status %d\n", + slave->dev_num, slave->status, status); + + if (status == SDW_SLAVE_UNATTACHED) { + dev_dbg(&slave->dev, + "initializing enumeration and init completion for Slave %d\n", + slave->dev_num); + + reinit_completion(&slave->enumeration_complete); + reinit_completion(&slave->initialization_complete); + + } else if ((status == SDW_SLAVE_ATTACHED) && + (slave->status == SDW_SLAVE_UNATTACHED)) { + dev_dbg(&slave->dev, + "signaling enumeration completion for Slave %d\n", + slave->dev_num); + + complete_all(&slave->enumeration_complete); + } + slave->status = status; + mutex_unlock(&bus->bus_lock); +} + +static int sdw_slave_clk_stop_callback(struct sdw_slave *slave, + enum sdw_clk_stop_mode mode, + enum sdw_clk_stop_type type) +{ + int ret = 0; + + mutex_lock(&slave->sdw_dev_lock); + + if (slave->probed) { + struct device *dev = &slave->dev; + struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); + + if (drv->ops && drv->ops->clk_stop) + ret = drv->ops->clk_stop(slave, mode, type); + } + + mutex_unlock(&slave->sdw_dev_lock); + + return ret; +} + +static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave, + enum sdw_clk_stop_mode mode, + bool prepare) +{ + bool wake_en; + u32 val = 0; + int ret; + + wake_en = slave->prop.wake_capable; + + if (prepare) { + val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP; + + if (mode == SDW_CLK_STOP_MODE1) + val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1; + + if (wake_en) + val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN; + } else { + ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL); + if (ret < 0) { + if (ret != -ENODATA) + dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret); + return ret; + } + val = ret; + val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP); + } + + ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val); + + if (ret < 0 && ret != -ENODATA) + dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret); + + return ret; +} + +static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num) +{ + int retry = bus->clk_stop_timeout; + int val; + + do { + val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT); + if (val < 0) { + if (val != -ENODATA) + dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val); + return val; + } + val &= SDW_SCP_STAT_CLK_STP_NF; + if (!val) { + dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n", + dev_num); + return 0; + } + + usleep_range(1000, 1500); + retry--; + } while (retry); + + dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n", + dev_num); + + return -ETIMEDOUT; +} + +/** + * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop + * + * @bus: SDW bus instance + * + * Query Slave for clock stop mode and prepare for that mode. + */ +int sdw_bus_prep_clk_stop(struct sdw_bus *bus) +{ + bool simple_clk_stop = true; + struct sdw_slave *slave; + bool is_slave = false; + int ret = 0; + + /* + * In order to save on transition time, prepare + * each Slave and then wait for all Slave(s) to be + * prepared for clock stop. + * If one of the Slave devices has lost sync and + * replies with Command Ignored/-ENODATA, we continue + * the loop + */ + list_for_each_entry(slave, &bus->slaves, node) { + if (!slave->dev_num) + continue; + + if (slave->status != SDW_SLAVE_ATTACHED && + slave->status != SDW_SLAVE_ALERT) + continue; + + /* Identify if Slave(s) are available on Bus */ + is_slave = true; + + ret = sdw_slave_clk_stop_callback(slave, + SDW_CLK_STOP_MODE0, + SDW_CLK_PRE_PREPARE); + if (ret < 0 && ret != -ENODATA) { + dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret); + return ret; + } + + /* Only prepare a Slave device if needed */ + if (!slave->prop.simple_clk_stop_capable) { + simple_clk_stop = false; + + ret = sdw_slave_clk_stop_prepare(slave, + SDW_CLK_STOP_MODE0, + true); + if (ret < 0 && ret != -ENODATA) { + dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret); + return ret; + } + } + } + + /* Skip remaining clock stop preparation if no Slave is attached */ + if (!is_slave) + return 0; + + /* + * Don't wait for all Slaves to be ready if they follow the simple + * state machine + */ + if (!simple_clk_stop) { + ret = sdw_bus_wait_for_clk_prep_deprep(bus, + SDW_BROADCAST_DEV_NUM); + /* + * if there are no Slave devices present and the reply is + * Command_Ignored/-ENODATA, we don't need to continue with the + * flow and can just return here. The error code is not modified + * and its handling left as an exercise for the caller. + */ + if (ret < 0) + return ret; + } + + /* Inform slaves that prep is done */ + list_for_each_entry(slave, &bus->slaves, node) { + if (!slave->dev_num) + continue; + + if (slave->status != SDW_SLAVE_ATTACHED && + slave->status != SDW_SLAVE_ALERT) + continue; + + ret = sdw_slave_clk_stop_callback(slave, + SDW_CLK_STOP_MODE0, + SDW_CLK_POST_PREPARE); + + if (ret < 0 && ret != -ENODATA) { + dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret); + return ret; + } + } + + return 0; +} +EXPORT_SYMBOL(sdw_bus_prep_clk_stop); + +/** + * sdw_bus_clk_stop: stop bus clock + * + * @bus: SDW bus instance + * + * After preparing the Slaves for clock stop, stop the clock by broadcasting + * write to SCP_CTRL register. + */ +int sdw_bus_clk_stop(struct sdw_bus *bus) +{ + int ret; + + /* + * broadcast clock stop now, attached Slaves will ACK this, + * unattached will ignore + */ + ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM, + SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW); + if (ret < 0) { + if (ret != -ENODATA) + dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret); + return ret; + } + + return 0; +} +EXPORT_SYMBOL(sdw_bus_clk_stop); + +/** + * sdw_bus_exit_clk_stop: Exit clock stop mode + * + * @bus: SDW bus instance + * + * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves + * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate + * back. + */ +int sdw_bus_exit_clk_stop(struct sdw_bus *bus) +{ + bool simple_clk_stop = true; + struct sdw_slave *slave; + bool is_slave = false; + int ret; + + /* + * In order to save on transition time, de-prepare + * each Slave and then wait for all Slave(s) to be + * de-prepared after clock resume. + */ + list_for_each_entry(slave, &bus->slaves, node) { + if (!slave->dev_num) + continue; + + if (slave->status != SDW_SLAVE_ATTACHED && + slave->status != SDW_SLAVE_ALERT) + continue; + + /* Identify if Slave(s) are available on Bus */ + is_slave = true; + + ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0, + SDW_CLK_PRE_DEPREPARE); + if (ret < 0) + dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret); + + /* Only de-prepare a Slave device if needed */ + if (!slave->prop.simple_clk_stop_capable) { + simple_clk_stop = false; + + ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0, + false); + + if (ret < 0) + dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret); + } + } + + /* Skip remaining clock stop de-preparation if no Slave is attached */ + if (!is_slave) + return 0; + + /* + * Don't wait for all Slaves to be ready if they follow the simple + * state machine + */ + if (!simple_clk_stop) { + ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM); + if (ret < 0) + dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret); + } + + list_for_each_entry(slave, &bus->slaves, node) { + if (!slave->dev_num) + continue; + + if (slave->status != SDW_SLAVE_ATTACHED && + slave->status != SDW_SLAVE_ALERT) + continue; + + ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0, + SDW_CLK_POST_DEPREPARE); + if (ret < 0) + dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret); + } + + return 0; +} +EXPORT_SYMBOL(sdw_bus_exit_clk_stop); + +int sdw_configure_dpn_intr(struct sdw_slave *slave, + int port, bool enable, int mask) +{ + u32 addr; + int ret; + u8 val = 0; + + if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) { + dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n", + enable ? "on" : "off"); + mask |= SDW_DPN_INT_TEST_FAIL; + } + + addr = SDW_DPN_INTMASK(port); + + /* Set/Clear port ready interrupt mask */ + if (enable) { + val |= mask; + val |= SDW_DPN_INT_PORT_READY; + } else { + val &= ~(mask); + val &= ~SDW_DPN_INT_PORT_READY; + } + + ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val); + if (ret < 0) + dev_err(&slave->dev, + "SDW_DPN_INTMASK write failed:%d\n", val); + + return ret; +} + +static int sdw_slave_set_frequency(struct sdw_slave *slave) +{ + u32 mclk_freq = slave->bus->prop.mclk_freq; + u32 curr_freq = slave->bus->params.curr_dr_freq >> 1; + unsigned int scale; + u8 scale_index; + u8 base; + int ret; + + /* + * frequency base and scale registers are required for SDCA + * devices. They may also be used for 1.2+/non-SDCA devices, + * but we will need a DisCo property to cover this case + */ + if (!slave->id.class_id) + return 0; + + if (!mclk_freq) { + dev_err(&slave->dev, + "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n"); + return -EINVAL; + } + + /* + * map base frequency using Table 89 of SoundWire 1.2 spec. + * The order of the tests just follows the specification, this + * is not a selection between possible values or a search for + * the best value but just a mapping. Only one case per platform + * is relevant. + * Some BIOS have inconsistent values for mclk_freq but a + * correct root so we force the mclk_freq to avoid variations. + */ + if (!(19200000 % mclk_freq)) { + mclk_freq = 19200000; + base = SDW_SCP_BASE_CLOCK_19200000_HZ; + } else if (!(24000000 % mclk_freq)) { + mclk_freq = 24000000; + base = SDW_SCP_BASE_CLOCK_24000000_HZ; + } else if (!(24576000 % mclk_freq)) { + mclk_freq = 24576000; + base = SDW_SCP_BASE_CLOCK_24576000_HZ; + } else if (!(22579200 % mclk_freq)) { + mclk_freq = 22579200; + base = SDW_SCP_BASE_CLOCK_22579200_HZ; + } else if (!(32000000 % mclk_freq)) { + mclk_freq = 32000000; + base = SDW_SCP_BASE_CLOCK_32000000_HZ; + } else { + dev_err(&slave->dev, + "Unsupported clock base, mclk %d\n", + mclk_freq); + return -EINVAL; + } + + if (mclk_freq % curr_freq) { + dev_err(&slave->dev, + "mclk %d is not multiple of bus curr_freq %d\n", + mclk_freq, curr_freq); + return -EINVAL; + } + + scale = mclk_freq / curr_freq; + + /* + * map scale to Table 90 of SoundWire 1.2 spec - and check + * that the scale is a power of two and maximum 64 + */ + scale_index = ilog2(scale); + + if (BIT(scale_index) != scale || scale_index > 6) { + dev_err(&slave->dev, + "No match found for scale %d, bus mclk %d curr_freq %d\n", + scale, mclk_freq, curr_freq); + return -EINVAL; + } + scale_index++; + + ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret); + return ret; + } + + /* initialize scale for both banks */ + ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret); + return ret; + } + ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index); + if (ret < 0) + dev_err(&slave->dev, + "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret); + + dev_dbg(&slave->dev, + "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n", + base, scale_index, mclk_freq, curr_freq); + + return ret; +} + +static int sdw_initialize_slave(struct sdw_slave *slave) +{ + struct sdw_slave_prop *prop = &slave->prop; + int status; + int ret; + u8 val; + + ret = sdw_slave_set_frequency(slave); + if (ret < 0) + return ret; + + if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) { + /* Clear bus clash interrupt before enabling interrupt mask */ + status = sdw_read_no_pm(slave, SDW_SCP_INT1); + if (status < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status); + return status; + } + if (status & SDW_SCP_INT1_BUS_CLASH) { + dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n"); + ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret); + return ret; + } + } + } + if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) && + !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) { + /* Clear parity interrupt before enabling interrupt mask */ + status = sdw_read_no_pm(slave, SDW_SCP_INT1); + if (status < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 (PARITY) read failed:%d\n", status); + return status; + } + if (status & SDW_SCP_INT1_PARITY) { + dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n"); + ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret); + return ret; + } + } + } + + /* + * Set SCP_INT1_MASK register, typically bus clash and + * implementation-defined interrupt mask. The Parity detection + * may not always be correct on startup so its use is + * device-dependent, it might e.g. only be enabled in + * steady-state after a couple of frames. + */ + val = slave->prop.scp_int1_mask; + + /* Enable SCP interrupts */ + ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INTMASK1 write failed:%d\n", ret); + return ret; + } + + /* No need to continue if DP0 is not present */ + if (!slave->prop.dp0_prop) + return 0; + + /* Enable DP0 interrupts */ + val = prop->dp0_prop->imp_def_interrupts; + val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE; + + ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val); + if (ret < 0) + dev_err(&slave->dev, + "SDW_DP0_INTMASK read failed:%d\n", ret); + return ret; +} + +static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status) +{ + u8 clear, impl_int_mask; + int status, status2, ret, count = 0; + + status = sdw_read_no_pm(slave, SDW_DP0_INT); + if (status < 0) { + dev_err(&slave->dev, + "SDW_DP0_INT read failed:%d\n", status); + return status; + } + + do { + clear = status & ~SDW_DP0_INTERRUPTS; + + if (status & SDW_DP0_INT_TEST_FAIL) { + dev_err(&slave->dev, "Test fail for port 0\n"); + clear |= SDW_DP0_INT_TEST_FAIL; + } + + /* + * Assumption: PORT_READY interrupt will be received only for + * ports implementing Channel Prepare state machine (CP_SM) + */ + + if (status & SDW_DP0_INT_PORT_READY) { + complete(&slave->port_ready[0]); + clear |= SDW_DP0_INT_PORT_READY; + } + + if (status & SDW_DP0_INT_BRA_FAILURE) { + dev_err(&slave->dev, "BRA failed\n"); + clear |= SDW_DP0_INT_BRA_FAILURE; + } + + impl_int_mask = SDW_DP0_INT_IMPDEF1 | + SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3; + + if (status & impl_int_mask) { + clear |= impl_int_mask; + *slave_status = clear; + } + + /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */ + ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_DP0_INT write failed:%d\n", ret); + return ret; + } + + /* Read DP0 interrupt again */ + status2 = sdw_read_no_pm(slave, SDW_DP0_INT); + if (status2 < 0) { + dev_err(&slave->dev, + "SDW_DP0_INT read failed:%d\n", status2); + return status2; + } + /* filter to limit loop to interrupts identified in the first status read */ + status &= status2; + + count++; + + /* we can get alerts while processing so keep retrying */ + } while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY)); + + if (count == SDW_READ_INTR_CLEAR_RETRY) + dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n"); + + return ret; +} + +static int sdw_handle_port_interrupt(struct sdw_slave *slave, + int port, u8 *slave_status) +{ + u8 clear, impl_int_mask; + int status, status2, ret, count = 0; + u32 addr; + + if (port == 0) + return sdw_handle_dp0_interrupt(slave, slave_status); + + addr = SDW_DPN_INT(port); + status = sdw_read_no_pm(slave, addr); + if (status < 0) { + dev_err(&slave->dev, + "SDW_DPN_INT read failed:%d\n", status); + + return status; + } + + do { + clear = status & ~SDW_DPN_INTERRUPTS; + + if (status & SDW_DPN_INT_TEST_FAIL) { + dev_err(&slave->dev, "Test fail for port:%d\n", port); + clear |= SDW_DPN_INT_TEST_FAIL; + } + + /* + * Assumption: PORT_READY interrupt will be received only + * for ports implementing CP_SM. + */ + if (status & SDW_DPN_INT_PORT_READY) { + complete(&slave->port_ready[port]); + clear |= SDW_DPN_INT_PORT_READY; + } + + impl_int_mask = SDW_DPN_INT_IMPDEF1 | + SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3; + + if (status & impl_int_mask) { + clear |= impl_int_mask; + *slave_status = clear; + } + + /* clear the interrupt but don't touch reserved fields */ + ret = sdw_write_no_pm(slave, addr, clear); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_DPN_INT write failed:%d\n", ret); + return ret; + } + + /* Read DPN interrupt again */ + status2 = sdw_read_no_pm(slave, addr); + if (status2 < 0) { + dev_err(&slave->dev, + "SDW_DPN_INT read failed:%d\n", status2); + return status2; + } + /* filter to limit loop to interrupts identified in the first status read */ + status &= status2; + + count++; + + /* we can get alerts while processing so keep retrying */ + } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY)); + + if (count == SDW_READ_INTR_CLEAR_RETRY) + dev_warn(&slave->dev, "Reached MAX_RETRY on port read"); + + return ret; +} + +static int sdw_handle_slave_alerts(struct sdw_slave *slave) +{ + struct sdw_slave_intr_status slave_intr; + u8 clear = 0, bit, port_status[15] = {0}; + int port_num, stat, ret, count = 0; + unsigned long port; + bool slave_notify; + u8 sdca_cascade = 0; + u8 buf, buf2[2], _buf, _buf2[2]; + bool parity_check; + bool parity_quirk; + + sdw_modify_slave_status(slave, SDW_SLAVE_ALERT); + + ret = pm_runtime_get_sync(&slave->dev); + if (ret < 0 && ret != -EACCES) { + dev_err(&slave->dev, "Failed to resume device: %d\n", ret); + pm_runtime_put_noidle(&slave->dev); + return ret; + } + + /* Read Intstat 1, Intstat 2 and Intstat 3 registers */ + ret = sdw_read_no_pm(slave, SDW_SCP_INT1); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 read failed:%d\n", ret); + goto io_err; + } + buf = ret; + + ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT2/3 read failed:%d\n", ret); + goto io_err; + } + + if (slave->prop.is_sdca) { + ret = sdw_read_no_pm(slave, SDW_DP0_INT); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_DP0_INT read failed:%d\n", ret); + goto io_err; + } + sdca_cascade = ret & SDW_DP0_SDCA_CASCADE; + } + + do { + slave_notify = false; + + /* + * Check parity, bus clash and Slave (impl defined) + * interrupt + */ + if (buf & SDW_SCP_INT1_PARITY) { + parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY; + parity_quirk = !slave->first_interrupt_done && + (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY); + + if (parity_check && !parity_quirk) + dev_err(&slave->dev, "Parity error detected\n"); + clear |= SDW_SCP_INT1_PARITY; + } + + if (buf & SDW_SCP_INT1_BUS_CLASH) { + if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH) + dev_err(&slave->dev, "Bus clash detected\n"); + clear |= SDW_SCP_INT1_BUS_CLASH; + } + + /* + * When bus clash or parity errors are detected, such errors + * are unlikely to be recoverable errors. + * TODO: In such scenario, reset bus. Make this configurable + * via sysfs property with bus reset being the default. + */ + + if (buf & SDW_SCP_INT1_IMPL_DEF) { + if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) { + dev_dbg(&slave->dev, "Slave impl defined interrupt\n"); + slave_notify = true; + } + clear |= SDW_SCP_INT1_IMPL_DEF; + } + + /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */ + if (sdca_cascade) + slave_notify = true; + + /* Check port 0 - 3 interrupts */ + port = buf & SDW_SCP_INT1_PORT0_3; + + /* To get port number corresponding to bits, shift it */ + port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port); + for_each_set_bit(bit, &port, 8) { + sdw_handle_port_interrupt(slave, bit, + &port_status[bit]); + } + + /* Check if cascade 2 interrupt is present */ + if (buf & SDW_SCP_INT1_SCP2_CASCADE) { + port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10; + for_each_set_bit(bit, &port, 8) { + /* scp2 ports start from 4 */ + port_num = bit + 4; + sdw_handle_port_interrupt(slave, + port_num, + &port_status[port_num]); + } + } + + /* now check last cascade */ + if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) { + port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14; + for_each_set_bit(bit, &port, 8) { + /* scp3 ports start from 11 */ + port_num = bit + 11; + sdw_handle_port_interrupt(slave, + port_num, + &port_status[port_num]); + } + } + + /* Update the Slave driver */ + if (slave_notify) { + mutex_lock(&slave->sdw_dev_lock); + + if (slave->probed) { + struct device *dev = &slave->dev; + struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); + + if (drv->ops && drv->ops->interrupt_callback) { + slave_intr.sdca_cascade = sdca_cascade; + slave_intr.control_port = clear; + memcpy(slave_intr.port, &port_status, + sizeof(slave_intr.port)); + + drv->ops->interrupt_callback(slave, &slave_intr); + } + } + + mutex_unlock(&slave->sdw_dev_lock); + } + + /* Ack interrupt */ + ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 write failed:%d\n", ret); + goto io_err; + } + + /* at this point all initial interrupt sources were handled */ + slave->first_interrupt_done = true; + + /* + * Read status again to ensure no new interrupts arrived + * while servicing interrupts. + */ + ret = sdw_read_no_pm(slave, SDW_SCP_INT1); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT1 recheck read failed:%d\n", ret); + goto io_err; + } + _buf = ret; + + ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_SCP_INT2/3 recheck read failed:%d\n", ret); + goto io_err; + } + + if (slave->prop.is_sdca) { + ret = sdw_read_no_pm(slave, SDW_DP0_INT); + if (ret < 0) { + dev_err(&slave->dev, + "SDW_DP0_INT recheck read failed:%d\n", ret); + goto io_err; + } + sdca_cascade = ret & SDW_DP0_SDCA_CASCADE; + } + + /* + * Make sure no interrupts are pending, but filter to limit loop + * to interrupts identified in the first status read + */ + buf &= _buf; + buf2[0] &= _buf2[0]; + buf2[1] &= _buf2[1]; + stat = buf || buf2[0] || buf2[1] || sdca_cascade; + + /* + * Exit loop if Slave is continuously in ALERT state even + * after servicing the interrupt multiple times. + */ + count++; + + /* we can get alerts while processing so keep retrying */ + } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY); + + if (count == SDW_READ_INTR_CLEAR_RETRY) + dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n"); + +io_err: + pm_runtime_mark_last_busy(&slave->dev); + pm_runtime_put_autosuspend(&slave->dev); + + return ret; +} + +static int sdw_update_slave_status(struct sdw_slave *slave, + enum sdw_slave_status status) +{ + int ret = 0; + + mutex_lock(&slave->sdw_dev_lock); + + if (slave->probed) { + struct device *dev = &slave->dev; + struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); + + if (drv->ops && drv->ops->update_status) + ret = drv->ops->update_status(slave, status); + } + + mutex_unlock(&slave->sdw_dev_lock); + + return ret; +} + +/** + * sdw_handle_slave_status() - Handle Slave status + * @bus: SDW bus instance + * @status: Status for all Slave(s) + */ +int sdw_handle_slave_status(struct sdw_bus *bus, + enum sdw_slave_status status[]) +{ + enum sdw_slave_status prev_status; + struct sdw_slave *slave; + bool attached_initializing, id_programmed; + int i, ret = 0; + + /* first check if any Slaves fell off the bus */ + for (i = 1; i <= SDW_MAX_DEVICES; i++) { + mutex_lock(&bus->bus_lock); + if (test_bit(i, bus->assigned) == false) { + mutex_unlock(&bus->bus_lock); + continue; + } + mutex_unlock(&bus->bus_lock); + + slave = sdw_get_slave(bus, i); + if (!slave) + continue; + + if (status[i] == SDW_SLAVE_UNATTACHED && + slave->status != SDW_SLAVE_UNATTACHED) { + dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n", + i, slave->status); + sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED); + + /* Ensure driver knows that peripheral unattached */ + ret = sdw_update_slave_status(slave, status[i]); + if (ret < 0) + dev_warn(&slave->dev, "Update Slave status failed:%d\n", ret); + } + } + + if (status[0] == SDW_SLAVE_ATTACHED) { + dev_dbg(bus->dev, "Slave attached, programming device number\n"); + + /* + * Programming a device number will have side effects, + * so we deal with other devices at a later time. + * This relies on those devices reporting ATTACHED, which will + * trigger another call to this function. This will only + * happen if at least one device ID was programmed. + * Error returns from sdw_program_device_num() are currently + * ignored because there's no useful recovery that can be done. + * Returning the error here could result in the current status + * of other devices not being handled, because if no device IDs + * were programmed there's nothing to guarantee a status change + * to trigger another call to this function. + */ + sdw_program_device_num(bus, &id_programmed); + if (id_programmed) + return 0; + } + + /* Continue to check other slave statuses */ + for (i = 1; i <= SDW_MAX_DEVICES; i++) { + mutex_lock(&bus->bus_lock); + if (test_bit(i, bus->assigned) == false) { + mutex_unlock(&bus->bus_lock); + continue; + } + mutex_unlock(&bus->bus_lock); + + slave = sdw_get_slave(bus, i); + if (!slave) + continue; + + attached_initializing = false; + + switch (status[i]) { + case SDW_SLAVE_UNATTACHED: + if (slave->status == SDW_SLAVE_UNATTACHED) + break; + + dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n", + i, slave->status); + + sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED); + break; + + case SDW_SLAVE_ALERT: + ret = sdw_handle_slave_alerts(slave); + if (ret < 0) + dev_err(&slave->dev, + "Slave %d alert handling failed: %d\n", + i, ret); + break; + + case SDW_SLAVE_ATTACHED: + if (slave->status == SDW_SLAVE_ATTACHED) + break; + + prev_status = slave->status; + sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED); + + if (prev_status == SDW_SLAVE_ALERT) + break; + + attached_initializing = true; + + ret = sdw_initialize_slave(slave); + if (ret < 0) + dev_err(&slave->dev, + "Slave %d initialization failed: %d\n", + i, ret); + + break; + + default: + dev_err(&slave->dev, "Invalid slave %d status:%d\n", + i, status[i]); + break; + } + + ret = sdw_update_slave_status(slave, status[i]); + if (ret < 0) + dev_err(&slave->dev, + "Update Slave status failed:%d\n", ret); + if (attached_initializing) { + dev_dbg(&slave->dev, + "signaling initialization completion for Slave %d\n", + slave->dev_num); + + complete_all(&slave->initialization_complete); + + /* + * If the manager became pm_runtime active, the peripherals will be + * restarted and attach, but their pm_runtime status may remain + * suspended. If the 'update_slave_status' callback initiates + * any sort of deferred processing, this processing would not be + * cancelled on pm_runtime suspend. + * To avoid such zombie states, we queue a request to resume. + * This would be a no-op in case the peripheral was being resumed + * by e.g. the ALSA/ASoC framework. + */ + pm_request_resume(&slave->dev); + } + } + + return ret; +} +EXPORT_SYMBOL(sdw_handle_slave_status); + +void sdw_clear_slave_status(struct sdw_bus *bus, u32 request) +{ + struct sdw_slave *slave; + int i; + + /* Check all non-zero devices */ + for (i = 1; i <= SDW_MAX_DEVICES; i++) { + mutex_lock(&bus->bus_lock); + if (test_bit(i, bus->assigned) == false) { + mutex_unlock(&bus->bus_lock); + continue; + } + mutex_unlock(&bus->bus_lock); + + slave = sdw_get_slave(bus, i); + if (!slave) + continue; + + if (slave->status != SDW_SLAVE_UNATTACHED) { + sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED); + slave->first_interrupt_done = false; + sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED); + } + + /* keep track of request, used in pm_runtime resume */ + slave->unattach_request = request; + } +} +EXPORT_SYMBOL(sdw_clear_slave_status); |