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path: root/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c
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Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/atombios_i2c.c')
-rw-r--r--drivers/gpu/drm/amd/amdgpu/atombios_i2c.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c b/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c
new file mode 100644
index 000000000000..13cdb01e9b45
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright 2011 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Alex Deucher
+ *
+ */
+#include <drm/drmP.h>
+#include <drm/amdgpu_drm.h>
+#include "amdgpu.h"
+#include "atom.h"
+#include "amdgpu_atombios.h"
+
+#define TARGET_HW_I2C_CLOCK 50
+
+/* these are a limitation of ProcessI2cChannelTransaction not the hw */
+#define ATOM_MAX_HW_I2C_WRITE 3
+#define ATOM_MAX_HW_I2C_READ 255
+
+static int amdgpu_atombios_i2c_process_i2c_ch(struct amdgpu_i2c_chan *chan,
+ u8 slave_addr, u8 flags,
+ u8 *buf, u8 num)
+{
+ struct drm_device *dev = chan->dev;
+ struct amdgpu_device *adev = dev->dev_private;
+ PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args;
+ 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 *)adev->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);
+ r = -EINVAL;
+ goto done;
+ }
+ if (buf == NULL)
+ args.ucRegIndex = 0;
+ else
+ args.ucRegIndex = buf[0];
+ if (num)
+ num--;
+ if (num)
+ memcpy(&out, &buf[1], num);
+ args.lpI2CDataOut = cpu_to_le16(out);
+ } else {
+ if (num > ATOM_MAX_HW_I2C_READ) {
+ DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num);
+ r = -EINVAL;
+ goto done;
+ }
+ args.ucRegIndex = 0;
+ args.lpI2CDataOut = 0;
+ }
+
+ args.ucFlag = flags;
+ args.ucI2CSpeed = TARGET_HW_I2C_CLOCK;
+ args.ucTransBytes = num;
+ args.ucSlaveAddr = slave_addr << 1;
+ args.ucLineNumber = chan->rec.i2c_id;
+
+ amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
+
+ /* error */
+ if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) {
+ DRM_DEBUG_KMS("hw_i2c error\n");
+ r = -EIO;
+ goto done;
+ }
+
+ if (!(flags & HW_I2C_WRITE))
+ amdgpu_atombios_copy_swap(buf, base, num, false);
+
+done:
+ mutex_unlock(&chan->mutex);
+
+ return r;
+}
+
+int amdgpu_atombios_i2c_xfer(struct i2c_adapter *i2c_adap,
+ struct i2c_msg *msgs, int num)
+{
+ struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
+ struct i2c_msg *p;
+ int i, remaining, current_count, buffer_offset, max_bytes, ret;
+ u8 flags;
+
+ /* check for bus probe */
+ p = &msgs[0];
+ if ((num == 1) && (p->len == 0)) {
+ ret = amdgpu_atombios_i2c_process_i2c_ch(i2c,
+ p->addr, HW_I2C_WRITE,
+ NULL, 0);
+ if (ret)
+ return ret;
+ else
+ return num;
+ }
+
+ for (i = 0; i < num; i++) {
+ p = &msgs[i];
+ remaining = p->len;
+ buffer_offset = 0;
+ /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */
+ if (p->flags & I2C_M_RD) {
+ max_bytes = ATOM_MAX_HW_I2C_READ;
+ flags = HW_I2C_READ;
+ } else {
+ max_bytes = ATOM_MAX_HW_I2C_WRITE;
+ flags = HW_I2C_WRITE;
+ }
+ while (remaining) {
+ if (remaining > max_bytes)
+ current_count = max_bytes;
+ else
+ current_count = remaining;
+ ret = amdgpu_atombios_i2c_process_i2c_ch(i2c,
+ p->addr, flags,
+ &p->buf[buffer_offset], current_count);
+ if (ret)
+ return ret;
+ remaining -= current_count;
+ buffer_offset += current_count;
+ }
+ }
+
+ return num;
+}
+
+u32 amdgpu_atombios_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+