1 files changed, 6 insertions, 195 deletions

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 08e33b8b13a4..79968e39c8d0 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -39,198 +39,6 @@
  * blocks, ...
  */
 
-/* Run a single AUX_CH I2C transaction, writing/reading data as necessary */
-static int
-i2c_algo_dp_aux_transaction(struct i2c_adapter *adapter, int mode,
-			    uint8_t write_byte, uint8_t *read_byte)
-{
-	struct i2c_algo_dp_aux_data *algo_data = adapter->algo_data;
-	int ret;
-
-	ret = (*algo_data->aux_ch)(adapter, mode,
-				   write_byte, read_byte);
-	return ret;
-}
-
-/*
- * I2C over AUX CH
- */
-
-/*
- * Send the address. If the I2C link is running, this 'restarts'
- * the connection with the new address, this is used for doing
- * a write followed by a read (as needed for DDC)
- */
-static int
-i2c_algo_dp_aux_address(struct i2c_adapter *adapter, u16 address, bool reading)
-{
-	struct i2c_algo_dp_aux_data *algo_data = adapter->algo_data;
-	int mode = MODE_I2C_START;
-	int ret;
-
-	if (reading)
-		mode |= MODE_I2C_READ;
-	else
-		mode |= MODE_I2C_WRITE;
-	algo_data->address = address;
-	algo_data->running = true;
-	ret = i2c_algo_dp_aux_transaction(adapter, mode, 0, NULL);
-	return ret;
-}
-
-/*
- * Stop the I2C transaction. This closes out the link, sending
- * a bare address packet with the MOT bit turned off
- */
-static void
-i2c_algo_dp_aux_stop(struct i2c_adapter *adapter, bool reading)
-{
-	struct i2c_algo_dp_aux_data *algo_data = adapter->algo_data;
-	int mode = MODE_I2C_STOP;
-
-	if (reading)
-		mode |= MODE_I2C_READ;
-	else
-		mode |= MODE_I2C_WRITE;
-	if (algo_data->running) {
-		(void) i2c_algo_dp_aux_transaction(adapter, mode, 0, NULL);
-		algo_data->running = false;
-	}
-}
-
-/*
- * Write a single byte to the current I2C address, the
- * the I2C link must be running or this returns -EIO
- */
-static int
-i2c_algo_dp_aux_put_byte(struct i2c_adapter *adapter, u8 byte)
-{
-	struct i2c_algo_dp_aux_data *algo_data = adapter->algo_data;
-	int ret;
-
-	if (!algo_data->running)
-		return -EIO;
-
-	ret = i2c_algo_dp_aux_transaction(adapter, MODE_I2C_WRITE, byte, NULL);
-	return ret;
-}
-
-/*
- * Read a single byte from the current I2C address, the
- * I2C link must be running or this returns -EIO
- */
-static int
-i2c_algo_dp_aux_get_byte(struct i2c_adapter *adapter, u8 *byte_ret)
-{
-	struct i2c_algo_dp_aux_data *algo_data = adapter->algo_data;
-	int ret;
-
-	if (!algo_data->running)
-		return -EIO;
-
-	ret = i2c_algo_dp_aux_transaction(adapter, MODE_I2C_READ, 0, byte_ret);
-	return ret;
-}
-
-static int
-i2c_algo_dp_aux_xfer(struct i2c_adapter *adapter,
-		     struct i2c_msg *msgs,
-		     int num)
-{
-	int ret = 0;
-	bool reading = false;
-	int m;
-	int b;
-
-	for (m = 0; m < num; m++) {
-		u16 len = msgs[m].len;
-		u8 *buf = msgs[m].buf;
-		reading = (msgs[m].flags & I2C_M_RD) != 0;
-		ret = i2c_algo_dp_aux_address(adapter, msgs[m].addr, reading);
-		if (ret < 0)
-			break;
-		if (reading) {
-			for (b = 0; b < len; b++) {
-				ret = i2c_algo_dp_aux_get_byte(adapter, &buf[b]);
-				if (ret < 0)
-					break;
-			}
-		} else {
-			for (b = 0; b < len; b++) {
-				ret = i2c_algo_dp_aux_put_byte(adapter, buf[b]);
-				if (ret < 0)
-					break;
-			}
-		}
-		if (ret < 0)
-			break;
-	}
-	if (ret >= 0)
-		ret = num;
-	i2c_algo_dp_aux_stop(adapter, reading);
-	DRM_DEBUG_KMS("dp_aux_xfer return %d\n", ret);
-	return ret;
-}
-
-static u32
-i2c_algo_dp_aux_functionality(struct i2c_adapter *adapter)
-{
-	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
-	       I2C_FUNC_SMBUS_READ_BLOCK_DATA |
-	       I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
-	       I2C_FUNC_10BIT_ADDR;
-}
-
-static const struct i2c_algorithm i2c_dp_aux_algo = {
-	.master_xfer	= i2c_algo_dp_aux_xfer,
-	.functionality	= i2c_algo_dp_aux_functionality,
-};
-
-static void
-i2c_dp_aux_reset_bus(struct i2c_adapter *adapter)
-{
-	(void) i2c_algo_dp_aux_address(adapter, 0, false);
-	(void) i2c_algo_dp_aux_stop(adapter, false);
-}
-
-static int
-i2c_dp_aux_prepare_bus(struct i2c_adapter *adapter)
-{
-	adapter->algo = &i2c_dp_aux_algo;
-	adapter->retries = 3;
-	i2c_dp_aux_reset_bus(adapter);
-	return 0;
-}
-
-/**
- * i2c_dp_aux_add_bus() - register an i2c adapter using the aux ch helper
- * @adapter: i2c adapter to register
- *
- * This registers an i2c adapter that uses dp aux channel as it's underlaying
- * transport. The driver needs to fill out the &i2c_algo_dp_aux_data structure
- * and store it in the algo_data member of the @adapter argument. This will be
- * used by the i2c over dp aux algorithm to drive the hardware.
- *
- * RETURNS:
- * 0 on success, -ERRNO on failure.
- *
- * IMPORTANT:
- * This interface is deprecated, please switch to the new dp aux helpers and
- * drm_dp_aux_register().
- */
-int
-i2c_dp_aux_add_bus(struct i2c_adapter *adapter)
-{
-	int error;
-
-	error = i2c_dp_aux_prepare_bus(adapter);
-	if (error)
-		return error;
-	error = i2c_add_adapter(adapter);
-	return error;
-}
-EXPORT_SYMBOL(i2c_dp_aux_add_bus);
-
 /* Helpers for DP link training */
 static u8 dp_link_status(const u8 link_status[DP_LINK_STATUS_SIZE], int r)
 {
@@ -378,10 +186,11 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
 
 	/*
 	 * The specification doesn't give any recommendation on how often to
-	 * retry native transactions, so retry 7 times like for I2C-over-AUX
-	 * transactions.
+	 * retry native transactions. We used to retry 7 times like for
+	 * aux i2c transactions but real world devices this wasn't
+	 * sufficient, bump to 32 which makes Dell 4k monitors happier.
 	 */
-	for (retry = 0; retry < 7; retry++) {
+	for (retry = 0; retry < 32; retry++) {
 
 		mutex_lock(&aux->hw_mutex);
 		err = aux->transfer(aux, &msg);
@@ -654,10 +463,12 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
 
 		case DP_AUX_I2C_REPLY_NACK:
 			DRM_DEBUG_KMS("I2C nack\n");
+			aux->i2c_nack_count++;
 			return -EREMOTEIO;
 
 		case DP_AUX_I2C_REPLY_DEFER:
 			DRM_DEBUG_KMS("I2C defer\n");
+			aux->i2c_defer_count++;
 			usleep_range(400, 500);
 			continue;