cregit-Linux how code gets into the kernel

Release 4.7 drivers/gpu/drm/radeon/radeon_dp_auxch.c

/*
 * Copyright 2015 Red Hat 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: Dave Airlie
 */
#include <drm/drmP.h>
#include <drm/radeon_drm.h>
#include "radeon.h"
#include "nid.h"


#define AUX_RX_ERROR_FLAGS (AUX_SW_RX_OVERFLOW |        \
                            AUX_SW_RX_HPD_DISCON |           \
                            AUX_SW_RX_PARTIAL_BYTE |         \
                            AUX_SW_NON_AUX_MODE |            \
                            AUX_SW_RX_SYNC_INVALID_L |       \
                            AUX_SW_RX_SYNC_INVALID_H |       \
                            AUX_SW_RX_INVALID_START |        \
                            AUX_SW_RX_RECV_NO_DET |          \
                            AUX_SW_RX_RECV_INVALID_H |       \
                            AUX_SW_RX_RECV_INVALID_V)


#define AUX_SW_REPLY_GET_BYTE_COUNT(x) (((x) >> 24) & 0x1f)


#define BARE_ADDRESS_SIZE 3


static const u32 aux_offset[] =
{
	0x6200 - 0x6200,
	0x6250 - 0x6200,
	0x62a0 - 0x6200,
	0x6300 - 0x6200,
	0x6350 - 0x6200,
	0x63a0 - 0x6200,
};


ssize_t radeon_dp_aux_transfer_native(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) { struct radeon_i2c_chan *chan = container_of(aux, struct radeon_i2c_chan, aux); struct drm_device *dev = chan->dev; struct radeon_device *rdev = dev->dev_private; int ret = 0, i; uint32_t tmp, ack = 0; int instance = chan->rec.i2c_id & 0xf; u8 byte; u8 *buf = msg->buffer; int retry_count = 0; int bytes; int msize; bool is_write = false; if (WARN_ON(msg->size > 16)) return -E2BIG; switch (msg->request & ~DP_AUX_I2C_MOT) { case DP_AUX_NATIVE_WRITE: case DP_AUX_I2C_WRITE: is_write = true; break; case DP_AUX_NATIVE_READ: case DP_AUX_I2C_READ: break; default: return -EINVAL; } /* work out two sizes required */ msize = 0; bytes = BARE_ADDRESS_SIZE; if (msg->size) { msize = msg->size - 1; bytes++; if (is_write) bytes += msg->size; } mutex_lock(&chan->mutex); /* switch the pad to aux mode */ tmp = RREG32(chan->rec.mask_clk_reg); tmp |= (1 << 16); WREG32(chan->rec.mask_clk_reg, tmp); /* setup AUX control register with correct HPD pin */ tmp = RREG32(AUX_CONTROL + aux_offset[instance]); tmp &= AUX_HPD_SEL(0x7); tmp |= AUX_HPD_SEL(chan->rec.hpd); tmp |= AUX_EN | AUX_LS_READ_EN | AUX_HPD_DISCON(0x1); WREG32(AUX_CONTROL + aux_offset[instance], tmp); /* atombios appears to write this twice lets copy it */ WREG32(AUX_SW_CONTROL + aux_offset[instance], AUX_SW_WR_BYTES(bytes)); WREG32(AUX_SW_CONTROL + aux_offset[instance], AUX_SW_WR_BYTES(bytes)); /* write the data header into the registers */ /* request, address, msg size */ byte = (msg->request << 4) | ((msg->address >> 16) & 0xf); WREG32(AUX_SW_DATA + aux_offset[instance], AUX_SW_DATA_MASK(byte) | AUX_SW_AUTOINCREMENT_DISABLE); byte = (msg->address >> 8) & 0xff; WREG32(AUX_SW_DATA + aux_offset[instance], AUX_SW_DATA_MASK(byte)); byte = msg->address & 0xff; WREG32(AUX_SW_DATA + aux_offset[instance], AUX_SW_DATA_MASK(byte)); byte = msize; WREG32(AUX_SW_DATA + aux_offset[instance], AUX_SW_DATA_MASK(byte)); /* if we are writing - write the msg buffer */ if (is_write) { for (i = 0; i < msg->size; i++) { WREG32(AUX_SW_DATA + aux_offset[instance], AUX_SW_DATA_MASK(buf[i])); } } /* clear the ACK */ WREG32(AUX_SW_INTERRUPT_CONTROL + aux_offset[instance], AUX_SW_DONE_ACK); /* write the size and GO bits */ WREG32(AUX_SW_CONTROL + aux_offset[instance], AUX_SW_WR_BYTES(bytes) | AUX_SW_GO); /* poll the status registers - TODO irq support */ do { tmp = RREG32(AUX_SW_STATUS + aux_offset[instance]); if (tmp & AUX_SW_DONE) { break; } usleep_range(100, 200); } while (retry_count++ < 1000); if (retry_count >= 1000) { DRM_ERROR("auxch hw never signalled completion, error %08x\n", tmp); ret = -EIO; goto done; } if (tmp & AUX_SW_RX_TIMEOUT) { DRM_DEBUG_KMS("dp_aux_ch timed out\n"); ret = -ETIMEDOUT; goto done; } if (tmp & AUX_RX_ERROR_FLAGS) { DRM_DEBUG_KMS("dp_aux_ch flags not zero: %08x\n", tmp); ret = -EIO; goto done; } bytes = AUX_SW_REPLY_GET_BYTE_COUNT(tmp); if (bytes) { WREG32(AUX_SW_DATA + aux_offset[instance], AUX_SW_DATA_RW | AUX_SW_AUTOINCREMENT_DISABLE); tmp = RREG32(AUX_SW_DATA + aux_offset[instance]); ack = (tmp >> 8) & 0xff; for (i = 0; i < bytes - 1; i++) { tmp = RREG32(AUX_SW_DATA + aux_offset[instance]); if (buf) buf[i] = (tmp >> 8) & 0xff; } if (buf) ret = bytes - 1; } WREG32(AUX_SW_INTERRUPT_CONTROL + aux_offset[instance], AUX_SW_DONE_ACK); if (is_write) ret = msg->size; done: mutex_unlock(&chan->mutex); if (ret >= 0) msg->reply = ack >> 4; return ret; }

Contributors

PersonTokensPropCommitsCommitProp
dave airliedave airlie73797.62%133.33%
alex deucheralex deucher131.72%133.33%
arindam natharindam nath50.66%133.33%
Total755100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
dave airliedave airlie79697.67%125.00%
alex deucheralex deucher141.72%250.00%
arindam natharindam nath50.61%125.00%
Total815100.00%4100.00%
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