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authorChris Wilson <chris@chris-wilson.co.uk>2016-06-17 11:33:17 +0300
committerDaniel Vetter <daniel.vetter@ffwll.ch>2016-06-17 15:38:04 +0300
commit0c2f6f1a561136a09c5de91889d0aa35e13f73d4 (patch)
treeaad07b7e38ca52eb8b981501b23e484fb0c35269 /drivers
parent1cee2a22e5e6f2332bff818ffd2dada0306c0d15 (diff)
downloadlinux-0c2f6f1a561136a09c5de91889d0aa35e13f73d4.tar.xz
drm: Pass the drm_dp_aux->hw_mutex to i2c for its locking
Rather than have both drm_dp_aux lock within its transfer, and i2c to lock around the transfer, use the same lock by filling in the locking callbacks that i2c wants to use. We require our own hw_mutex as we bypass i2c_transfer for drm_dp_dpcd_access(). Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Dave Airlie <airlied@redhat.com> Cc: Rafael Antognolli <rafael.antognolli@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: dri-devel@lists.freedesktop.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1466152398-20157-2-git-send-email-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers')
-rw-r--r--drivers/gpu/drm/drm_dp_helper.c28
1 files changed, 24 insertions, 4 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index eeaf5a7c3aa7..4b088afa21b2 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -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;
}
@@ -774,6 +770,26 @@ 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
* @aux: DisplayPort AUX channel
@@ -790,6 +806,10 @@ int drm_dp_aux_register(struct drm_dp_aux *aux)
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;
+
aux->ddc.class = I2C_CLASS_DDC;
aux->ddc.owner = THIS_MODULE;
aux->ddc.dev.parent = aux->dev;