// SPDX-License-Identifier: MIT
/*
* 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*/
#include <linux/i2c-algo-bit.h>
#include <linux/i2c.h>
#include <drm/drm_managed.h>
#include <drm/drm_print.h>
#include "ast_ddc.h"
#include "ast_drv.h"
struct ast_ddc {
struct ast_device *ast;
struct i2c_algo_bit_data bit;
struct i2c_adapter adapter;
};
static void ast_ddc_algo_bit_data_setsda(void *data, int state)
{
struct ast_ddc *ddc = data;
struct ast_device *ast = ddc->ast;
int i;
u8 ujcrb7, jtemp;
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((state & 0x01) ? 0 : 1) << 2;
ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0xf1, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x04);
if (ujcrb7 == jtemp)
break;
}
}
static void ast_ddc_algo_bit_data_setscl(void *data, int state)
{
struct ast_ddc *ddc = data;
struct ast_device *ast = ddc->ast;
int i;
u8 ujcrb7, jtemp;
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((state & 0x01) ? 0 : 1);
ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0xf4, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x01);
if (ujcrb7 == jtemp)
break;
}
}
static int ast_ddc_algo_bit_data_pre_xfer(struct i2c_adapter *adapter)
{
struct ast_ddc *ddc = i2c_get_adapdata(adapter);
struct ast_device *ast = ddc->ast;
/*
* Protect access to I/O registers from concurrent modesetting
* by acquiring the I/O-register lock.
*/
mutex_lock(&ast->modeset_lock);
return 0;
}
static void ast_ddc_algo_bit_data_post_xfer(struct i2c_adapter *adapter)
{
struct ast_ddc *ddc = i2c_get_adapdata(adapter);
struct ast_device *ast = ddc->ast;
mutex_unlock(&ast->modeset_lock);
}
static int ast_ddc_algo_bit_data_getsda(void *data)
{
struct ast_ddc *ddc = data;
struct ast_device *ast = ddc->ast;
uint32_t val, val2, count, pass;
count = 0;
pass = 0;
val = (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x20) >> 5) & 0x01;
do {
val2 = (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x20) >> 5) & 0x01;
if (val == val2) {
pass++;
} else {
pass = 0;
val = (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x20) >> 5) & 0x01;
}
} while ((pass < 5) && (count++ < 0x10000));
return val & 1 ? 1 : 0;
}
static int ast_ddc_algo_bit_data_getscl(void *data)
{
struct ast_ddc *ddc = data;
struct ast_device *ast = ddc->ast;
uint32_t val, val2, count, pass;
count = 0;
pass = 0;
val = (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x10) >> 4) & 0x01;
do {
val2 = (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x10) >> 4) & 0x01;
if (val == val2) {
pass++;
} else {
pass = 0;
val = (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xb7, 0x10) >> 4) & 0x01;
}
} while ((pass < 5) && (count++ < 0x10000));
return val & 1 ? 1 : 0;
}
static void ast_ddc_release(struct drm_device *dev, void *res)
{
struct ast_ddc *ddc = res;
i2c_del_adapter(&ddc->adapter);
}
struct i2c_adapter *ast_ddc_create(struct ast_device *ast)
{
struct drm_device *dev = &ast->base;
struct ast_ddc *ddc;
struct i2c_adapter *adapter;
struct i2c_algo_bit_data *bit;
int ret;
ddc = drmm_kzalloc(dev, sizeof(*ddc), GFP_KERNEL);
if (!ddc)
return ERR_PTR(-ENOMEM);
ddc->ast = ast;
bit = &ddc->bit;
bit->data = ddc;
bit->setsda = ast_ddc_algo_bit_data_setsda;
bit->setscl = ast_ddc_algo_bit_data_setscl;
bit->getsda = ast_ddc_algo_bit_data_getsda;
bit->getscl = ast_ddc_algo_bit_data_getscl;
bit->pre_xfer = ast_ddc_algo_bit_data_pre_xfer;
bit->post_xfer = ast_ddc_algo_bit_data_post_xfer;
bit->udelay = 20;
bit->timeout = usecs_to_jiffies(2200);
adapter = &ddc->adapter;
adapter->owner = THIS_MODULE;
adapter->algo_data = bit;
adapter->dev.parent = dev->dev;
snprintf(adapter->name, sizeof(adapter->name), "AST DDC bus");
i2c_set_adapdata(adapter, ddc);
ret = i2c_bit_add_bus(adapter);
if (ret) {
drm_err(dev, "Failed to register bit i2c\n");
return ERR_PTR(ret);
}
ret = drmm_add_action_or_reset(dev, ast_ddc_release, ddc);
if (ret)
return ERR_PTR(ret);
return &ddc->adapter;
}
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