diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 72 |
1 files changed, 66 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index d83447557f9..63424d5db9c 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -33,7 +33,7 @@ #include "intel_drv.h" #include "i915_drm.h" #include "i915_drv.h" -#include "intel_dp.h" +#include "drm_dp_helper.h" #define DP_LINK_STATUS_SIZE 6 #define DP_LINK_CHECK_TIMEOUT (10 * 1000) @@ -382,17 +382,77 @@ intel_dp_aux_native_read(struct intel_output *intel_output, } static int -intel_dp_i2c_aux_ch(struct i2c_adapter *adapter, - uint8_t *send, int send_bytes, - uint8_t *recv, int recv_bytes) +intel_dp_i2c_aux_ch(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; struct intel_dp_priv *dp_priv = container_of(adapter, struct intel_dp_priv, adapter); struct intel_output *intel_output = dp_priv->intel_output; + uint16_t address = algo_data->address; + uint8_t msg[5]; + uint8_t reply[2]; + int msg_bytes; + int reply_bytes; + int ret; + + /* Set up the command byte */ + if (mode & MODE_I2C_READ) + msg[0] = AUX_I2C_READ << 4; + else + msg[0] = AUX_I2C_WRITE << 4; + + if (!(mode & MODE_I2C_STOP)) + msg[0] |= AUX_I2C_MOT << 4; + + msg[1] = address >> 8; + msg[2] = address; + + switch (mode) { + case MODE_I2C_WRITE: + msg[3] = 0; + msg[4] = write_byte; + msg_bytes = 5; + reply_bytes = 1; + break; + case MODE_I2C_READ: + msg[3] = 0; + msg_bytes = 4; + reply_bytes = 2; + break; + default: + msg_bytes = 3; + reply_bytes = 1; + break; + } - return intel_dp_aux_ch(intel_output, - send, send_bytes, recv, recv_bytes); + for (;;) { + ret = intel_dp_aux_ch(intel_output, + msg, msg_bytes, + reply, reply_bytes); + if (ret < 0) { + DRM_DEBUG("aux_ch failed %d\n", ret); + return ret; + } + switch (reply[0] & AUX_I2C_REPLY_MASK) { + case AUX_I2C_REPLY_ACK: + if (mode == MODE_I2C_READ) { + *read_byte = reply[1]; + } + return reply_bytes - 1; + case AUX_I2C_REPLY_NACK: + DRM_DEBUG("aux_ch nack\n"); + return -EREMOTEIO; + case AUX_I2C_REPLY_DEFER: + DRM_DEBUG("aux_ch defer\n"); + udelay(100); + break; + default: + DRM_ERROR("aux_ch invalid reply 0x%02x\n", reply[0]); + return -EREMOTEIO; + } + } } static int |