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path: root/drivers/gpu/drm/i915/intel_dp_i2c.c
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Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp_i2c.c')
-rw-r--r--drivers/gpu/drm/i915/intel_dp_i2c.c273
1 files changed, 0 insertions, 273 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp_i2c.c b/drivers/gpu/drm/i915/intel_dp_i2c.c
deleted file mode 100644
index a63b6f57d2d4..000000000000
--- a/drivers/gpu/drm/i915/intel_dp_i2c.c
+++ /dev/null
@@ -1,273 +0,0 @@
-/*
- * Copyright © 2009 Keith Packard
- *
- * Permission to use, copy, modify, distribute, and sell this software and its
- * documentation for any purpose is hereby granted without fee, provided that
- * the above copyright notice appear in all copies and that both that copyright
- * notice and this permission notice appear in supporting documentation, and
- * that the name of the copyright holders not be used in advertising or
- * publicity pertaining to distribution of the software without specific,
- * written prior permission. The copyright holders make no representations
- * about the suitability of this software for any purpose. It is provided "as
- * is" without express or implied warranty.
- *
- * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
- * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
- * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
- * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
- * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
- * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
- * OF THIS SOFTWARE.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/slab.h>
-#include <linux/init.h>
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/i2c.h>
-#include "intel_dp.h"
-#include "drmP.h"
-
-/* Run a single AUX_CH I2C transaction, writing/reading data as necessary */
-
-#define MODE_I2C_START 1
-#define MODE_I2C_WRITE 2
-#define MODE_I2C_READ 4
-#define MODE_I2C_STOP 8
-
-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;
- 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;
- }
-
- for (;;) {
- ret = (*algo_data->aux_ch)(adapter,
- 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;
- }
- }
-}
-
-/*
- * 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("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;
-}
-
-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);
generated by cgit v1.2.3 (git 2.39.0) at 2025-01-21 18:19:57 +0300