From d52d7a1be02cc6da287bfaea7eebb0de1a77fbe2 Mon Sep 17 00:00:00 2001 From: Sanyog Kale Date: Thu, 14 Dec 2017 11:19:39 +0530 Subject: soundwire: Add Slave status handling helpers SoundWire Slaves report status to bus. Add helpers to handle the status changes. Signed-off-by: Hardik T Shah Signed-off-by: Sanyog Kale Reviewed-by: Philippe Ombredanne Acked-By: Pierre-Louis Bossart Reviewed-by: Takashi Iwai Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/soundwire/bus.c | 214 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/soundwire/bus.h | 14 ++++ 2 files changed, 228 insertions(+) (limited to 'drivers/soundwire') diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index fb9008d..e306bd4 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -374,6 +374,93 @@ int sdw_write(struct sdw_slave *slave, u32 addr, u8 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.unique_id != id.unique_id) || + (slave->id.mfg_id != id.mfg_id) || + (slave->id.part_id != id.part_id) || + (slave->id.class_id != id.class_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; + + /* check first if device number is assigned, if so reuse that */ + if (!slave->dev_num) { + 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", + dev_num); + return dev_num; + } + } else { + dev_info(slave->bus->dev, + "Slave already registered dev_num:%d", + 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(slave, SDW_SCP_DEVNUMBER, dev_num); + if (ret < 0) { + dev_err(&slave->dev, "Program device_num failed: %d", ret); + return ret; + } + + /* After xfer of msg, restore dev_num */ + slave->dev_num = dev_num; + + return 0; +} + void sdw_extract_slave_id(struct sdw_bus *bus, u64 addr, struct sdw_slave_id *id) { @@ -402,3 +489,130 @@ void sdw_extract_slave_id(struct sdw_bus *bus, 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 */ + 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) | + (buf[2] << 24) | ((unsigned long long)buf[1] << 32) | + ((unsigned long long)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", + ret); + return ret; + } + + break; + } + } + + if (found == false) { + /* TODO: Park this device in Group 13 */ + dev_err(bus->dev, "Slave Entry not found"); + } + + 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); + slave->status = status; + mutex_unlock(&slave->bus->bus_lock); +} + +static int sdw_initialize_slave(struct sdw_slave *slave) +{ + struct sdw_slave_prop *prop = &slave->prop; + int ret; + u8 val; + + /* + * 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", 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->device_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", ret); + return val; + } + + return 0; +} diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index 48eb7de..e8df55d 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -52,4 +52,18 @@ int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg, int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave, u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf); +/* Read-Modify-Write Slave register */ +static inline 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); +} + #endif /* __SDW_BUS_H */ -- cgit v1.1