// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) // Copyright(c) 2015-17 Intel Corporation. #include #include #include #include #include #include #include "bus.h" #include "sysfs_local.h" static DEFINE_IDA(sdw_ida); static int sdw_get_id(struct sdw_bus *bus) { int rc = ida_alloc(&sdw_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) { dev_err(parent, "Failed to get bus id\n"); return ret; } ret = sdw_master_device_add(bus, parent, fwnode); if (ret) { 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; } 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 * TODO: populate this flag by reading property from FW node */ 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) { 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); 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_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; } /** * 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 = do_transfer(bus, msg); if (ret != 0 && ret != -ENODATA) dev_err(bus->dev, "trf on Slave %d failed:%d\n", msg->dev_num, ret); if (msg->page) sdw_reset_page(bus, msg->dev_num); mutex_unlock(&bus->msg_lock); return ret; } /** * 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; return sdw_transfer(slave->bus, &msg); } static int sdw_nwrite_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_WRITE, val); if (ret < 0) return ret; return sdw_transfer(slave->bus, &msg); } static int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value) { return sdw_nwrite_no_pm(slave, addr, 1, &value); } 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) 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) return ret; return sdw_transfer(bus, &msg); } static 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; } /** * 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->bus->dev); if (ret < 0 && ret != -EACCES) { pm_runtime_put_noidle(slave->bus->dev); return ret; } ret = sdw_nread_no_pm(slave, addr, count, val); pm_runtime_mark_last_busy(slave->bus->dev); pm_runtime_put(slave->bus->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 read */ int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) { int ret; ret = pm_runtime_get_sync(slave->bus->dev); if (ret < 0 && ret != -EACCES) { pm_runtime_put_noidle(slave->bus->dev); return ret; } ret = sdw_nwrite_no_pm(slave, addr, count, val); pm_runtime_mark_last_busy(slave->bus->dev); pm_runtime_put(slave->bus->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 = NULL; list_for_each_entry(slave, &bus->slaves, node) { if (slave->dev_num == i) return slave; } return NULL; } static 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; } /* called with bus_lock held */ static int sdw_get_device_num(struct sdw_slave *slave) { int bit; 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) { 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(slave->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(slave->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(&slave->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 %x, part_id %x, mfg_id %x, unique_id %x, version %x\n", id->class_id, id->part_id, id->mfg_id, id->unique_id, id->sdw_version); } static int sdw_program_device_num(struct sdw_bus *bus) { u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0}; struct sdw_slave *slave, *_s; struct sdw_slave_id id; struct sdw_msg msg; bool found = false; int count = 0, ret; u64 addr; /* 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); /* Now compare with entries */ list_for_each_entry_safe(slave, _s, &bus->slaves, node) { if (sdw_compare_devid(slave, id) == 0) { found = true; /* * 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) { dev_err(slave->bus->dev, "Assign dev_num failed:%d\n", ret); return ret; } break; } } if (!found) { /* TODO: Park this device in Group 13 */ 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) { mutex_lock(&slave->bus->bus_lock); dev_vdbg(&slave->dev, "%s: changing status slave %d status %d new status %d\n", __func__, slave->dev_num, slave->status, status); if (status == SDW_SLAVE_UNATTACHED) { dev_dbg(&slave->dev, "%s: initializing completion for Slave %d\n", __func__, slave->dev_num); init_completion(&slave->enumeration_complete); init_completion(&slave->initialization_complete); } else if ((status == SDW_SLAVE_ATTACHED) && (slave->status == SDW_SLAVE_UNATTACHED)) { dev_dbg(&slave->dev, "%s: signaling completion for Slave %d\n", __func__, slave->dev_num); complete(&slave->enumeration_complete); } slave->status = status; mutex_unlock(&slave->bus->bus_lock); } static enum sdw_clk_stop_mode sdw_get_clk_stop_mode(struct sdw_slave *slave) { enum sdw_clk_stop_mode mode; /* * Query for clock stop mode if Slave implements * ops->get_clk_stop_mode, else read from property. */ if (slave->ops && slave->ops->get_clk_stop_mode) { mode = slave->ops->get_clk_stop_mode(slave); } else { if (slave->prop.clk_stop_mode1) mode = SDW_CLK_STOP_MODE1; else mode = SDW_CLK_STOP_MODE0; } return mode; } 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; if (slave->ops && slave->ops->clk_stop) { ret = slave->ops->clk_stop(slave, mode, type); if (ret < 0) { dev_err(&slave->dev, "Clk Stop type =%d failed: %d\n", type, ret); return ret; } } return 0; } 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 { val = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL); val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP); } ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val); if (ret != 0) dev_err(&slave->dev, "Clock Stop prepare failed for slave: %d", 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) & SDW_SCP_STAT_CLK_STP_NF; if (!val) { dev_info(bus->dev, "clock stop prep/de-prep done slave:%d", dev_num); return 0; } usleep_range(1000, 1500); retry--; } while (retry); dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d", 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) { enum sdw_clk_stop_mode slave_mode; 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. */ 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; slave_mode = sdw_get_clk_stop_mode(slave); slave->curr_clk_stop_mode = slave_mode; ret = sdw_slave_clk_stop_callback(slave, slave_mode, SDW_CLK_PRE_PREPARE); if (ret < 0) { dev_err(&slave->dev, "pre-prepare failed:%d", ret); return ret; } ret = sdw_slave_clk_stop_prepare(slave, slave_mode, true); if (ret < 0) { dev_err(&slave->dev, "pre-prepare failed:%d", ret); return ret; } if (slave_mode == SDW_CLK_STOP_MODE1) simple_clk_stop = false; } if (is_slave && !simple_clk_stop) { ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM); if (ret < 0) return ret; } /* Don't need to inform slaves if there is no slave attached */ if (!is_slave) 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; slave_mode = slave->curr_clk_stop_mode; if (slave_mode == SDW_CLK_STOP_MODE1) { ret = sdw_slave_clk_stop_callback(slave, slave_mode, SDW_CLK_POST_PREPARE); if (ret < 0) { dev_err(&slave->dev, "post-prepare failed:%d", ret); } } } return ret; } 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_dbg(bus->dev, "ClockStopNow Broadcast msg ignored %d", ret); else dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d", 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) { enum sdw_clk_stop_mode mode; 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; mode = slave->curr_clk_stop_mode; if (mode == SDW_CLK_STOP_MODE1) { simple_clk_stop = false; continue; } ret = sdw_slave_clk_stop_callback(slave, mode, SDW_CLK_PRE_DEPREPARE); if (ret < 0) dev_warn(&slave->dev, "clk stop deprep failed:%d", ret); ret = sdw_slave_clk_stop_prepare(slave, mode, false); if (ret < 0) dev_warn(&slave->dev, "clk stop deprep failed:%d", ret); } if (is_slave && !simple_clk_stop) sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM); /* * Don't need to call slave callback function if there is no slave * attached */ if (!is_slave) return 0; 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; mode = slave->curr_clk_stop_mode; sdw_slave_clk_stop_callback(slave, mode, SDW_CLK_POST_DEPREPARE); } 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; 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->bus->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(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(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(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 ret; u8 val; ret = sdw_slave_set_frequency(slave); if (ret < 0) return ret; /* * Set bus clash, parity and SCP implementation * defined interrupt mask * TODO: Read implementation defined interrupt mask * from Slave property */ val = SDW_SCP_INT1_IMPL_DEF | SDW_SCP_INT1_BUS_CLASH | SDW_SCP_INT1_PARITY; /* Enable SCP interrupts */ ret = sdw_update(slave, SDW_SCP_INTMASK1, val, val); if (ret < 0) { dev_err(slave->bus->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(slave, SDW_DP0_INTMASK, val, val); if (ret < 0) dev_err(slave->bus->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 = 0, impl_int_mask; int status, status2, ret, count = 0; status = sdw_read(slave, SDW_DP0_INT); if (status < 0) { dev_err(slave->bus->dev, "SDW_DP0_INT read failed:%d\n", status); return status; } do { 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 interrupt */ ret = sdw_write(slave, SDW_DP0_INT, clear); if (ret < 0) { dev_err(slave->bus->dev, "SDW_DP0_INT write failed:%d\n", ret); return ret; } /* Read DP0 interrupt again */ status2 = sdw_read(slave, SDW_DP0_INT); if (status2 < 0) { dev_err(slave->bus->dev, "SDW_DP0_INT read failed:%d\n", status2); return status2; } status &= status2; count++; /* we can get alerts while processing so keep retrying */ } while (status != 0 && count < SDW_READ_INTR_CLEAR_RETRY); if (count == SDW_READ_INTR_CLEAR_RETRY) dev_warn(slave->bus->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 = 0, 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(slave, addr); if (status < 0) { dev_err(slave->bus->dev, "SDW_DPN_INT read failed:%d\n", status); return status; } do { 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 */ ret = sdw_write(slave, addr, clear); if (ret < 0) { dev_err(slave->bus->dev, "SDW_DPN_INT write failed:%d\n", ret); return ret; } /* Read DPN interrupt again */ status2 = sdw_read(slave, addr); if (status2 < 0) { dev_err(slave->bus->dev, "SDW_DPN_INT read failed:%d\n", status2); return status2; } status &= status2; count++; /* we can get alerts while processing so keep retrying */ } while (status != 0 && count < SDW_READ_INTR_CLEAR_RETRY); if (count == SDW_READ_INTR_CLEAR_RETRY) dev_warn(slave->bus->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 = false; u8 buf, buf2[2], _buf, _buf2[2]; 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->bus->dev); return ret; } /* Read Instat 1, Instat 2 and Instat 3 registers */ ret = sdw_read(slave, SDW_SCP_INT1); if (ret < 0) { dev_err(slave->bus->dev, "SDW_SCP_INT1 read failed:%d\n", ret); goto io_err; } buf = ret; ret = sdw_nread(slave, SDW_SCP_INTSTAT2, 2, buf2); if (ret < 0) { dev_err(slave->bus->dev, "SDW_SCP_INT2/3 read failed:%d\n", ret); goto io_err; } do { /* * Check parity, bus clash and Slave (impl defined) * interrupt */ if (buf & SDW_SCP_INT1_PARITY) { dev_err(&slave->dev, "Parity error detected\n"); clear |= SDW_SCP_INT1_PARITY; } if (buf & SDW_SCP_INT1_BUS_CLASH) { dev_err(&slave->dev, "Bus clash error 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) { dev_dbg(&slave->dev, "Slave impl defined interrupt\n"); clear |= SDW_SCP_INT1_IMPL_DEF; 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 + 3; 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 + 10; sdw_handle_port_interrupt(slave, port_num, &port_status[port_num]); } } /* Update the Slave driver */ if (slave_notify && slave->ops && slave->ops->interrupt_callback) { slave_intr.control_port = clear; memcpy(slave_intr.port, &port_status, sizeof(slave_intr.port)); slave->ops->interrupt_callback(slave, &slave_intr); } /* Ack interrupt */ ret = sdw_write(slave, SDW_SCP_INT1, clear); if (ret < 0) { dev_err(slave->bus->dev, "SDW_SCP_INT1 write failed:%d\n", ret); goto io_err; } /* * Read status again to ensure no new interrupts arrived * while servicing interrupts. */ ret = sdw_read(slave, SDW_SCP_INT1); if (ret < 0) { dev_err(slave->bus->dev, "SDW_SCP_INT1 read failed:%d\n", ret); goto io_err; } _buf = ret; ret = sdw_nread(slave, SDW_SCP_INTSTAT2, 2, _buf2); if (ret < 0) { dev_err(slave->bus->dev, "SDW_SCP_INT2/3 read failed:%d\n", ret); goto io_err; } /* Make sure no interrupts are pending */ buf &= _buf; buf2[0] &= _buf2[0]; buf2[1] &= _buf2[1]; stat = buf || buf2[0] || buf2[1]; /* * 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->bus->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) { unsigned long time; if (!slave->probed) { /* * the slave status update is typically handled in an * interrupt thread, which can race with the driver * probe, e.g. when a module needs to be loaded. * * make sure the probe is complete before updating * status. */ time = wait_for_completion_timeout(&slave->probe_complete, msecs_to_jiffies(DEFAULT_PROBE_TIMEOUT)); if (!time) { dev_err(&slave->dev, "Probe not complete, timed out\n"); return -ETIMEDOUT; } } if (!slave->ops || !slave->ops->update_status) return 0; return slave->ops->update_status(slave, status); } /** * 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; 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) sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED); } if (status[0] == SDW_SLAVE_ATTACHED) { dev_dbg(bus->dev, "Slave attached, programming device number\n"); ret = sdw_program_device_num(bus); if (ret) dev_err(bus->dev, "Slave attach failed: %d\n", ret); /* * programming a device number will have side effects, * so we deal with other devices at a later time */ return ret; } /* 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; sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED); break; case SDW_SLAVE_ALERT: ret = sdw_handle_slave_alerts(slave); if (ret) dev_err(bus->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) dev_err(bus->dev, "Slave %d initialization failed: %d\n", i, ret); break; default: dev_err(bus->dev, "Invalid slave %d status:%d\n", i, status[i]); break; } ret = sdw_update_slave_status(slave, status[i]); if (ret) dev_err(slave->bus->dev, "Update Slave status failed:%d\n", ret); if (attached_initializing) complete(&slave->initialization_complete); } 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); /* keep track of request, used in pm_runtime resume */ slave->unattach_request = request; } } EXPORT_SYMBOL(sdw_clear_slave_status);