diff options
Diffstat (limited to 'drivers/gpu/drm/drm_dp_helper.c')
-rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 58 |
1 files changed, 48 insertions, 10 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index eeaf5a7..8f11b87 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -203,7 +203,7 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request, ret = aux->transfer(aux, &msg); - if (ret > 0) { + if (ret >= 0) { native_reply = msg.reply & DP_AUX_NATIVE_REPLY_MASK; if (native_reply == DP_AUX_NATIVE_REPLY_ACK) { if (ret == size) @@ -708,8 +708,6 @@ static int drm_dp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, memset(&msg, 0, sizeof(msg)); - mutex_lock(&aux->hw_mutex); - for (i = 0; i < num; i++) { msg.address = msgs[i].addr; drm_dp_i2c_msg_set_request(&msg, &msgs[i]); @@ -764,8 +762,6 @@ static int drm_dp_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, msg.size = 0; (void)drm_dp_i2c_do_msg(aux, &msg); - mutex_unlock(&aux->hw_mutex); - return err; } @@ -774,22 +770,64 @@ static const struct i2c_algorithm drm_dp_i2c_algo = { .master_xfer = drm_dp_i2c_xfer, }; +static struct drm_dp_aux *i2c_to_aux(struct i2c_adapter *i2c) +{ + return container_of(i2c, struct drm_dp_aux, ddc); +} + +static void lock_bus(struct i2c_adapter *i2c, unsigned int flags) +{ + mutex_lock(&i2c_to_aux(i2c)->hw_mutex); +} + +static int trylock_bus(struct i2c_adapter *i2c, unsigned int flags) +{ + return mutex_trylock(&i2c_to_aux(i2c)->hw_mutex); +} + +static void unlock_bus(struct i2c_adapter *i2c, unsigned int flags) +{ + mutex_unlock(&i2c_to_aux(i2c)->hw_mutex); +} + /** - * drm_dp_aux_register() - initialise and register aux channel + * drm_dp_aux_init() - minimally initialise an aux channel * @aux: DisplayPort AUX channel * - * Returns 0 on success or a negative error code on failure. + * If you need to use the drm_dp_aux's i2c adapter prior to registering it + * with the outside world, call drm_dp_aux_init() first. You must still + * call drm_dp_aux_register() once the connector has been registered to + * allow userspace access to the auxiliary DP channel. */ -int drm_dp_aux_register(struct drm_dp_aux *aux) +void drm_dp_aux_init(struct drm_dp_aux *aux) { - int ret; - mutex_init(&aux->hw_mutex); aux->ddc.algo = &drm_dp_i2c_algo; aux->ddc.algo_data = aux; aux->ddc.retries = 3; + aux->ddc.lock_bus = lock_bus; + aux->ddc.trylock_bus = trylock_bus; + aux->ddc.unlock_bus = unlock_bus; +} +EXPORT_SYMBOL(drm_dp_aux_init); + +/** + * drm_dp_aux_register() - initialise and register aux channel + * @aux: DisplayPort AUX channel + * + * Automatically calls drm_dp_aux_init() if this hasn't been done yet. + * + * Returns 0 on success or a negative error code on failure. + */ +int drm_dp_aux_register(struct drm_dp_aux *aux) +{ + int ret; + + if (!aux->ddc.algo) + drm_dp_aux_init(aux); + aux->ddc.class = I2C_CLASS_DDC; aux->ddc.owner = THIS_MODULE; aux->ddc.dev.parent = aux->dev; |