Messages in this thread Patch in this message | | | Subject | Re: [alsa-devel] [PATCH v4 08/15] soundwire: Add Slave status handling helpers | From | Pierre-Louis Bossart <> | Date | Fri, 1 Dec 2017 17:36:47 -0600 |
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On 12/1/17 3:56 AM, Vinod Koul wrote: > From: Sanyog Kale <sanyog.r.kale@intel.com> > > SoundWire Slaves report status to bus. Add helpers to handle > the status changes. > > Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com> > Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com> > Signed-off-by: Vinod Koul <vinod.koul@intel.com> > --- > drivers/soundwire/bus.c | 202 ++++++++++++++++++++++++++++++++++++++++++ > drivers/soundwire/bus.h | 14 +++ > include/linux/soundwire/sdw.h | 1 + > 3 files changed, 217 insertions(+) > > diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c > index 2f108f162905..09126ddd3cdd 100644 > --- a/drivers/soundwire/bus.c > +++ b/drivers/soundwire/bus.c > @@ -372,6 +372,93 @@ 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;
My brain is starting to fry but is this correct? Bit11 seems like a valid value. Should it be bit > 15 (assuming bit 12,13,14 are set to avoid using groups and master)?
> + } > + > + /* > + * 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) > { > @@ -400,3 +487,118 @@ 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, NULL, &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++; > + > + } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
explain that the last condition is intentional - this is not a bug -, some devices can drop off during enumeration and rejoin so might be counted twice.
> + > + 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 and parity interrupt mask */ > + val = 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 bde5f840ca96..b491e86f2c4c 100644 > --- a/drivers/soundwire/bus.h > +++ b/drivers/soundwire/bus.h > @@ -53,4 +53,18 @@ int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_slave *slave, > 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 */ > diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h > index d3337b5b882b..09619d042909 100644 > --- a/include/linux/soundwire/sdw.h > +++ b/include/linux/soundwire/sdw.h > @@ -15,6 +15,7 @@ struct sdw_slave; > /* SDW Enumeration Device Number */ > #define SDW_ENUM_DEV_NUM 0 > > +#define SDW_NUM_DEV_ID_REGISTERS 6 > #define SDW_MAX_DEVICES 11 > > /** >
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