diff options
Diffstat (limited to 'drivers/i3c/master.c')
| -rw-r--r-- | drivers/i3c/master.c | 95 |
1 files changed, 93 insertions, 2 deletions
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index 95caa16270..3afa530c5e 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -557,6 +557,88 @@ static ssize_t i2c_scl_frequency_show(struct device *dev, } static DEVICE_ATTR_RO(i2c_scl_frequency); +static int i3c_set_hotjoin(struct i3c_master_controller *master, bool enable) +{ + int ret; + + if (!master || !master->ops) + return -EINVAL; + + if (!master->ops->enable_hotjoin || !master->ops->disable_hotjoin) + return -EINVAL; + + i3c_bus_normaluse_lock(&master->bus); + + if (enable) + ret = master->ops->enable_hotjoin(master); + else + ret = master->ops->disable_hotjoin(master); + + master->hotjoin = enable; + + i3c_bus_normaluse_unlock(&master->bus); + + return ret; +} + +static ssize_t hotjoin_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i3c_bus *i3cbus = dev_to_i3cbus(dev); + int ret; + bool res; + + if (!i3cbus->cur_master) + return -EINVAL; + + if (kstrtobool(buf, &res)) + return -EINVAL; + + ret = i3c_set_hotjoin(i3cbus->cur_master->common.master, res); + if (ret) + return ret; + + return count; +} + +/* + * i3c_master_enable_hotjoin - Enable hotjoin + * @master: I3C master object + * + * Return: a 0 in case of success, an negative error code otherwise. + */ +int i3c_master_enable_hotjoin(struct i3c_master_controller *master) +{ + return i3c_set_hotjoin(master, true); +} +EXPORT_SYMBOL_GPL(i3c_master_enable_hotjoin); + +/* + * i3c_master_disable_hotjoin - Disable hotjoin + * @master: I3C master object + * + * Return: a 0 in case of success, an negative error code otherwise. + */ +int i3c_master_disable_hotjoin(struct i3c_master_controller *master) +{ + return i3c_set_hotjoin(master, false); +} +EXPORT_SYMBOL_GPL(i3c_master_disable_hotjoin); + +static ssize_t hotjoin_show(struct device *dev, struct device_attribute *da, char *buf) +{ + struct i3c_bus *i3cbus = dev_to_i3cbus(dev); + ssize_t ret; + + i3c_bus_normaluse_lock(i3cbus); + ret = sysfs_emit(buf, "%d\n", i3cbus->cur_master->common.master->hotjoin); + i3c_bus_normaluse_unlock(i3cbus); + + return ret; +} + +static DEVICE_ATTR_RW(hotjoin); + static struct attribute *i3c_masterdev_attrs[] = { &dev_attr_mode.attr, &dev_attr_current_master.attr, @@ -567,6 +649,7 @@ static struct attribute *i3c_masterdev_attrs[] = { &dev_attr_pid.attr, &dev_attr_dynamic_address.attr, &dev_attr_hdrcap.attr, + &dev_attr_hotjoin.attr, NULL, }; ATTRIBUTE_GROUPS(i3c_masterdev); @@ -1130,8 +1213,16 @@ static int i3c_master_getmxds_locked(struct i3c_master_controller *master, i3c_ccc_cmd_init(&cmd, true, I3C_CCC_GETMXDS, &dest, 1); ret = i3c_master_send_ccc_cmd_locked(master, &cmd); - if (ret) - goto out; + if (ret) { + /* + * Retry when the device does not support max read turnaround + * while expecting shorter length from this CCC command. + */ + dest.payload.len -= 3; + ret = i3c_master_send_ccc_cmd_locked(master, &cmd); + if (ret) + goto out; + } if (dest.payload.len != 2 && dest.payload.len != 5) { ret = -EIO; |