alistair23-linux/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c
Grazvydas Ignotas 2f9ba199da drm/amdgpu: warn if dp aux is still attached on free
If this happens (and it recently did), we free a structure while part of
it is still in use, which results in non-obvious crashes. The way it's
detached is not trivial (DRM core has to call the connector .destroy
callback and things must be torn down in the right order), so better
detect it and warn early.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2016-10-06 12:39:03 -04:00

395 lines
10 KiB
C

/*
* Copyright 2007-8 Advanced Micro Devices, Inc.
* Copyright 2008 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
* Alex Deucher
*/
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_edid.h>
#include <drm/amdgpu_drm.h>
#include "amdgpu.h"
#include "amdgpu_i2c.h"
#include "amdgpu_atombios.h"
#include "atom.h"
#include "atombios_dp.h"
#include "atombios_i2c.h"
/* bit banging i2c */
static int amdgpu_i2c_pre_xfer(struct i2c_adapter *i2c_adap)
{
struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
struct amdgpu_device *adev = i2c->dev->dev_private;
struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
uint32_t temp;
mutex_lock(&i2c->mutex);
/* switch the pads to ddc mode */
if (rec->hw_capable) {
temp = RREG32(rec->mask_clk_reg);
temp &= ~(1 << 16);
WREG32(rec->mask_clk_reg, temp);
}
/* clear the output pin values */
temp = RREG32(rec->a_clk_reg) & ~rec->a_clk_mask;
WREG32(rec->a_clk_reg, temp);
temp = RREG32(rec->a_data_reg) & ~rec->a_data_mask;
WREG32(rec->a_data_reg, temp);
/* set the pins to input */
temp = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
WREG32(rec->en_clk_reg, temp);
temp = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
WREG32(rec->en_data_reg, temp);
/* mask the gpio pins for software use */
temp = RREG32(rec->mask_clk_reg) | rec->mask_clk_mask;
WREG32(rec->mask_clk_reg, temp);
temp = RREG32(rec->mask_clk_reg);
temp = RREG32(rec->mask_data_reg) | rec->mask_data_mask;
WREG32(rec->mask_data_reg, temp);
temp = RREG32(rec->mask_data_reg);
return 0;
}
static void amdgpu_i2c_post_xfer(struct i2c_adapter *i2c_adap)
{
struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
struct amdgpu_device *adev = i2c->dev->dev_private;
struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
uint32_t temp;
/* unmask the gpio pins for software use */
temp = RREG32(rec->mask_clk_reg) & ~rec->mask_clk_mask;
WREG32(rec->mask_clk_reg, temp);
temp = RREG32(rec->mask_clk_reg);
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 amdgpu_i2c_get_clock(void *i2c_priv)
{
struct amdgpu_i2c_chan *i2c = i2c_priv;
struct amdgpu_device *adev = i2c->dev->dev_private;
struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
uint32_t val;
/* read the value off the pin */
val = RREG32(rec->y_clk_reg);
val &= rec->y_clk_mask;
return (val != 0);
}
static int amdgpu_i2c_get_data(void *i2c_priv)
{
struct amdgpu_i2c_chan *i2c = i2c_priv;
struct amdgpu_device *adev = i2c->dev->dev_private;
struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
uint32_t val;
/* read the value off the pin */
val = RREG32(rec->y_data_reg);
val &= rec->y_data_mask;
return (val != 0);
}
static void amdgpu_i2c_set_clock(void *i2c_priv, int clock)
{
struct amdgpu_i2c_chan *i2c = i2c_priv;
struct amdgpu_device *adev = i2c->dev->dev_private;
struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
uint32_t val;
/* set pin direction */
val = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
val |= clock ? 0 : rec->en_clk_mask;
WREG32(rec->en_clk_reg, val);
}
static void amdgpu_i2c_set_data(void *i2c_priv, int data)
{
struct amdgpu_i2c_chan *i2c = i2c_priv;
struct amdgpu_device *adev = i2c->dev->dev_private;
struct amdgpu_i2c_bus_rec *rec = &i2c->rec;
uint32_t val;
/* set pin direction */
val = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
val |= data ? 0 : rec->en_data_mask;
WREG32(rec->en_data_reg, val);
}
static const struct i2c_algorithm amdgpu_atombios_i2c_algo = {
.master_xfer = amdgpu_atombios_i2c_xfer,
.functionality = amdgpu_atombios_i2c_func,
};
struct amdgpu_i2c_chan *amdgpu_i2c_create(struct drm_device *dev,
const struct amdgpu_i2c_bus_rec *rec,
const char *name)
{
struct amdgpu_i2c_chan *i2c;
int ret;
/* don't add the mm_i2c bus unless hw_i2c is enabled */
if (rec->mm_i2c && (amdgpu_hw_i2c == 0))
return NULL;
i2c = kzalloc(sizeof(struct amdgpu_i2c_chan), GFP_KERNEL);
if (i2c == NULL)
return NULL;
i2c->rec = *rec;
i2c->adapter.owner = THIS_MODULE;
i2c->adapter.class = I2C_CLASS_DDC;
i2c->adapter.dev.parent = &dev->pdev->dev;
i2c->dev = dev;
i2c_set_adapdata(&i2c->adapter, i2c);
mutex_init(&i2c->mutex);
if (rec->hw_capable &&
amdgpu_hw_i2c) {
/* hw i2c using atom */
snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
"AMDGPU i2c hw bus %s", name);
i2c->adapter.algo = &amdgpu_atombios_i2c_algo;
ret = i2c_add_adapter(&i2c->adapter);
if (ret)
goto out_free;
} else {
/* set the amdgpu bit adapter */
snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
"AMDGPU i2c bit bus %s", name);
i2c->adapter.algo_data = &i2c->bit;
i2c->bit.pre_xfer = amdgpu_i2c_pre_xfer;
i2c->bit.post_xfer = amdgpu_i2c_post_xfer;
i2c->bit.setsda = amdgpu_i2c_set_data;
i2c->bit.setscl = amdgpu_i2c_set_clock;
i2c->bit.getsda = amdgpu_i2c_get_data;
i2c->bit.getscl = amdgpu_i2c_get_clock;
i2c->bit.udelay = 10;
i2c->bit.timeout = usecs_to_jiffies(2200); /* from VESA */
i2c->bit.data = i2c;
ret = i2c_bit_add_bus(&i2c->adapter);
if (ret) {
DRM_ERROR("Failed to register bit i2c %s\n", name);
goto out_free;
}
}
return i2c;
out_free:
kfree(i2c);
return NULL;
}
void amdgpu_i2c_destroy(struct amdgpu_i2c_chan *i2c)
{
if (!i2c)
return;
WARN_ON(i2c->has_aux);
i2c_del_adapter(&i2c->adapter);
kfree(i2c);
}
/* Add the default buses */
void amdgpu_i2c_init(struct amdgpu_device *adev)
{
if (amdgpu_hw_i2c)
DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");
if (adev->is_atom_bios)
amdgpu_atombios_i2c_init(adev);
}
/* remove all the buses */
void amdgpu_i2c_fini(struct amdgpu_device *adev)
{
int i;
for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) {
if (adev->i2c_bus[i]) {
amdgpu_i2c_destroy(adev->i2c_bus[i]);
adev->i2c_bus[i] = NULL;
}
}
}
/* Add additional buses */
void amdgpu_i2c_add(struct amdgpu_device *adev,
const struct amdgpu_i2c_bus_rec *rec,
const char *name)
{
struct drm_device *dev = adev->ddev;
int i;
for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) {
if (!adev->i2c_bus[i]) {
adev->i2c_bus[i] = amdgpu_i2c_create(dev, rec, name);
return;
}
}
}
/* looks up bus based on id */
struct amdgpu_i2c_chan *
amdgpu_i2c_lookup(struct amdgpu_device *adev,
const struct amdgpu_i2c_bus_rec *i2c_bus)
{
int i;
for (i = 0; i < AMDGPU_MAX_I2C_BUS; i++) {
if (adev->i2c_bus[i] &&
(adev->i2c_bus[i]->rec.i2c_id == i2c_bus->i2c_id)) {
return adev->i2c_bus[i];
}
}
return NULL;
}
static void amdgpu_i2c_get_byte(struct amdgpu_i2c_chan *i2c_bus,
u8 slave_addr,
u8 addr,
u8 *val)
{
u8 out_buf[2];
u8 in_buf[2];
struct i2c_msg msgs[] = {
{
.addr = slave_addr,
.flags = 0,
.len = 1,
.buf = out_buf,
},
{
.addr = slave_addr,
.flags = I2C_M_RD,
.len = 1,
.buf = in_buf,
}
};
out_buf[0] = addr;
out_buf[1] = 0;
if (i2c_transfer(&i2c_bus->adapter, msgs, 2) == 2) {
*val = in_buf[0];
DRM_DEBUG("val = 0x%02x\n", *val);
} else {
DRM_DEBUG("i2c 0x%02x 0x%02x read failed\n",
addr, *val);
}
}
static void amdgpu_i2c_put_byte(struct amdgpu_i2c_chan *i2c_bus,
u8 slave_addr,
u8 addr,
u8 val)
{
uint8_t out_buf[2];
struct i2c_msg msg = {
.addr = slave_addr,
.flags = 0,
.len = 2,
.buf = out_buf,
};
out_buf[0] = addr;
out_buf[1] = val;
if (i2c_transfer(&i2c_bus->adapter, &msg, 1) != 1)
DRM_DEBUG("i2c 0x%02x 0x%02x write failed\n",
addr, val);
}
/* ddc router switching */
void
amdgpu_i2c_router_select_ddc_port(const struct amdgpu_connector *amdgpu_connector)
{
u8 val;
if (!amdgpu_connector->router.ddc_valid)
return;
if (!amdgpu_connector->router_bus)
return;
amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x3, &val);
val &= ~amdgpu_connector->router.ddc_mux_control_pin;
amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x3, val);
amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x1, &val);
val &= ~amdgpu_connector->router.ddc_mux_control_pin;
val |= amdgpu_connector->router.ddc_mux_state;
amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x1, val);
}
/* clock/data router switching */
void
amdgpu_i2c_router_select_cd_port(const struct amdgpu_connector *amdgpu_connector)
{
u8 val;
if (!amdgpu_connector->router.cd_valid)
return;
if (!amdgpu_connector->router_bus)
return;
amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x3, &val);
val &= ~amdgpu_connector->router.cd_mux_control_pin;
amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x3, val);
amdgpu_i2c_get_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x1, &val);
val &= ~amdgpu_connector->router.cd_mux_control_pin;
val |= amdgpu_connector->router.cd_mux_state;
amdgpu_i2c_put_byte(amdgpu_connector->router_bus,
amdgpu_connector->router.i2c_addr,
0x1, val);
}