From 831719d62f692e28699a7acd7b441c6f0c01b6f7 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Thu, 8 May 2014 10:58:04 -0400 Subject: [PATCH] drm/radeon: add a i2c bus mutex MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The i2c and aux buses use the same pads so add a mutex to protect access to the pads. Signed-off-by: Alex Deucher Signed-off-by: Christian König --- drivers/gpu/drm/radeon/atombios_dp.c | 18 ++++++++++++++---- drivers/gpu/drm/radeon/atombios_i2c.c | 17 +++++++++++++---- drivers/gpu/drm/radeon/radeon_i2c.c | 9 +++++++++ drivers/gpu/drm/radeon/radeon_mode.h | 1 + 4 files changed, 37 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c index bc0119fb6c12..330f8df65b09 100644 --- a/drivers/gpu/drm/radeon/atombios_dp.c +++ b/drivers/gpu/drm/radeon/atombios_dp.c @@ -95,9 +95,12 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan, int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction); unsigned char *base; int recv_bytes; + int r = 0; memset(&args, 0, sizeof(args)); + mutex_lock(&chan->mutex); + base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1); radeon_atom_copy_swap(base, send, send_bytes, true); @@ -117,19 +120,22 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan, /* timeout */ if (args.v1.ucReplyStatus == 1) { DRM_DEBUG_KMS("dp_aux_ch timeout\n"); - return -ETIMEDOUT; + r = -ETIMEDOUT; + goto done; } /* flags not zero */ if (args.v1.ucReplyStatus == 2) { DRM_DEBUG_KMS("dp_aux_ch flags not zero\n"); - return -EBUSY; + r = -EBUSY; + goto done; } /* error */ if (args.v1.ucReplyStatus == 3) { DRM_DEBUG_KMS("dp_aux_ch error\n"); - return -EIO; + r = -EIO; + goto done; } recv_bytes = args.v1.ucDataOutLen; @@ -139,7 +145,11 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan, if (recv && recv_size) radeon_atom_copy_swap(recv, base + 16, recv_bytes, false); - return recv_bytes; + r = recv_bytes; +done: + mutex_unlock(&chan->mutex); + + return r; } #define BARE_ADDRESS_SIZE 3 diff --git a/drivers/gpu/drm/radeon/atombios_i2c.c b/drivers/gpu/drm/radeon/atombios_i2c.c index b5162c3b6111..9c570fb15b8c 100644 --- a/drivers/gpu/drm/radeon/atombios_i2c.c +++ b/drivers/gpu/drm/radeon/atombios_i2c.c @@ -43,15 +43,19 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction); unsigned char *base; u16 out = cpu_to_le16(0); + int r = 0; memset(&args, 0, sizeof(args)); + mutex_lock(&chan->mutex); + base = (unsigned char *)rdev->mode_info.atom_context->scratch; if (flags & HW_I2C_WRITE) { if (num > ATOM_MAX_HW_I2C_WRITE) { DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 3)\n", num); - return -EINVAL; + r = -EINVAL; + goto done; } if (buf == NULL) args.ucRegIndex = 0; @@ -65,7 +69,8 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, } else { if (num > ATOM_MAX_HW_I2C_READ) { DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num); - return -EINVAL; + r = -EINVAL; + goto done; } args.ucRegIndex = 0; args.lpI2CDataOut = 0; @@ -82,13 +87,17 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, /* error */ if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) { DRM_DEBUG_KMS("hw_i2c error\n"); - return -EIO; + r = -EIO; + goto done; } if (!(flags & HW_I2C_WRITE)) radeon_atom_copy_swap(buf, base, num, false); - return 0; +done: + mutex_unlock(&chan->mutex); + + return r; } int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap, diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c b/drivers/gpu/drm/radeon/radeon_i2c.c index 7b944142a9fd..427ee4d6d0b5 100644 --- a/drivers/gpu/drm/radeon/radeon_i2c.c +++ b/drivers/gpu/drm/radeon/radeon_i2c.c @@ -94,6 +94,8 @@ static int pre_xfer(struct i2c_adapter *i2c_adap) struct radeon_i2c_bus_rec *rec = &i2c->rec; uint32_t temp; + mutex_lock(&i2c->mutex); + /* RV410 appears to have a bug where the hw i2c in reset * holds the i2c port in a bad state - switch hw i2c away before * doing DDC - do this for all r200s/r300s/r400s for safety sake @@ -170,6 +172,8 @@ static void post_xfer(struct i2c_adapter *i2c_adap) temp = RREG32(rec->mask_data_reg) & ~rec->mask_data_mask; WREG32(rec->mask_data_reg, temp); temp = RREG32(rec->mask_data_reg); + + mutex_unlock(&i2c->mutex); } static int get_clock(void *i2c_priv) @@ -813,6 +817,8 @@ static int radeon_hw_i2c_xfer(struct i2c_adapter *i2c_adap, struct radeon_i2c_bus_rec *rec = &i2c->rec; int ret = 0; + mutex_lock(&i2c->mutex); + switch (rdev->family) { case CHIP_R100: case CHIP_RV100: @@ -879,6 +885,8 @@ static int radeon_hw_i2c_xfer(struct i2c_adapter *i2c_adap, break; } + mutex_unlock(&i2c->mutex); + return ret; } @@ -919,6 +927,7 @@ struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev, i2c->adapter.dev.parent = &dev->pdev->dev; i2c->dev = dev; i2c_set_adapdata(&i2c->adapter, i2c); + mutex_init(&i2c->mutex); if (rec->mm_i2c || (rec->hw_capable && radeon_hw_i2c && diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h index 6ddf31a2d34e..b265a8b95fe6 100644 --- a/drivers/gpu/drm/radeon/radeon_mode.h +++ b/drivers/gpu/drm/radeon/radeon_mode.h @@ -191,6 +191,7 @@ struct radeon_i2c_chan { struct radeon_i2c_bus_rec rec; struct drm_dp_aux aux; bool has_aux; + struct mutex mutex; }; /* mostly for macs, but really any system without connector tables */ -- 2.20.1