/*
 * 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 "drmP.h"
#include "radeon_drm.h"
#include "radeon.h"

/**
 * radeon_ddc_probe
 *
 */
bool radeon_ddc_probe(struct radeon_connector *radeon_connector)
{
        u8 out_buf[] = { 0x0, 0x0};
        u8 buf[2];
        int ret;
        struct i2c_msg msgs[] = {
                {
                        .addr = 0x50,
                        .flags = 0,
                        .len = 1,
                        .buf = out_buf,
                },
                {
                        .addr = 0x50,
                        .flags = I2C_M_RD,
                        .len = 1,
                        .buf = buf,
                }
        };

        ret = i2c_transfer(&radeon_connector->ddc_bus->adapter, msgs, 2);
        if (ret == 2)
                return true;

        return false;
}


void radeon_i2c_do_lock(struct radeon_connector *radeon_connector, int lock_state)
{
        struct radeon_device *rdev = radeon_connector->base.dev->dev_private;
        uint32_t temp;
        struct radeon_i2c_bus_rec *rec = &radeon_connector->ddc_bus->rec;

        /* RV410 appears to have a bug where the hw i2c in reset
         * holds the i2c port in a bad state - switch hw i2c away before
         * doing DDC - do this for all r200s/r300s/r400s for safety sake
         */
        if ((rdev->family >= CHIP_R200) && !ASIC_IS_AVIVO(rdev)) {
                if (rec->a_clk_reg == RADEON_GPIO_MONID) {
                        WREG32(RADEON_DVI_I2C_CNTL_0, (RADEON_I2C_SOFT_RST |
                                                R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1)));
                } else {
                        WREG32(RADEON_DVI_I2C_CNTL_0, (RADEON_I2C_SOFT_RST |
                                                R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3)));
                }
        }
        if (lock_state) {
                temp = RREG32(rec->a_clk_reg);
                temp &= ~(rec->a_clk_mask);
                WREG32(rec->a_clk_reg, temp);

                temp = RREG32(rec->a_data_reg);
                temp &= ~(rec->a_data_mask);
                WREG32(rec->a_data_reg, temp);
        }

        temp = RREG32(rec->mask_clk_reg);
        if (lock_state)
                temp |= rec->mask_clk_mask;
        else
                temp &= ~rec->mask_clk_mask;
        WREG32(rec->mask_clk_reg, temp);
        temp = RREG32(rec->mask_clk_reg);

        temp = RREG32(rec->mask_data_reg);
        if (lock_state)
                temp |= rec->mask_data_mask;
        else
                temp &= ~rec->mask_data_mask;
        WREG32(rec->mask_data_reg, temp);
        temp = RREG32(rec->mask_data_reg);
}

static int get_clock(void *i2c_priv)
{
        struct radeon_i2c_chan *i2c = i2c_priv;
        struct radeon_device *rdev = i2c->dev->dev_private;
        struct radeon_i2c_bus_rec *rec = &i2c->rec;
        uint32_t val;

        val = RREG32(rec->get_clk_reg);
        val &= rec->get_clk_mask;

        return (val != 0);
}


static int get_data(void *i2c_priv)
{
        struct radeon_i2c_chan *i2c = i2c_priv;
        struct radeon_device *rdev = i2c->dev->dev_private;
        struct radeon_i2c_bus_rec *rec = &i2c->rec;
        uint32_t val;

        val = RREG32(rec->get_data_reg);
        val &= rec->get_data_mask;
        return (val != 0);
}

static void set_clock(void *i2c_priv, int clock)
{
        struct radeon_i2c_chan *i2c = i2c_priv;
        struct radeon_device *rdev = i2c->dev->dev_private;
        struct radeon_i2c_bus_rec *rec = &i2c->rec;
        uint32_t val;

        val = RREG32(rec->put_clk_reg) & (uint32_t)~(rec->put_clk_mask);
        val |= clock ? 0 : rec->put_clk_mask;
        WREG32(rec->put_clk_reg, val);
}

static void set_data(void *i2c_priv, int data)
{
        struct radeon_i2c_chan *i2c = i2c_priv;
        struct radeon_device *rdev = i2c->dev->dev_private;
        struct radeon_i2c_bus_rec *rec = &i2c->rec;
        uint32_t val;

        val = RREG32(rec->put_data_reg) & (uint32_t)~(rec->put_data_mask);
        val |= data ? 0 : rec->put_data_mask;
        WREG32(rec->put_data_reg, val);
}

struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev,
                struct radeon_i2c_bus_rec *rec,
                const char *name)
{
        struct radeon_i2c_chan *i2c;
        int ret;

        i2c = kzalloc(sizeof(struct radeon_i2c_chan), GFP_KERNEL);
        if (i2c == NULL)
                return NULL;

        i2c->adapter.owner = THIS_MODULE;
        i2c->adapter.algo_data = &i2c->algo;
        i2c->dev = dev;
        i2c->algo.setsda = set_data;
        i2c->algo.setscl = set_clock;
        i2c->algo.getsda = get_data;
        i2c->algo.getscl = get_clock;
        i2c->algo.udelay = 20;
        /* vesa says 2.2 ms is enough, 1 jiffy doesn't seem to always
         * make this, 2 jiffies is a lot more reliable */
        i2c->algo.timeout = 2;
        i2c->algo.data = i2c;
        i2c->rec = *rec;
        i2c_set_adapdata(&i2c->adapter, i2c);

        ret = i2c_bit_add_bus(&i2c->adapter);
        if (ret) {
                DRM_INFO("Failed to register i2c %s\n", name);
                goto out_free;
        }

        return i2c;
out_free:
        kfree(i2c);
        return NULL;

}

void radeon_i2c_destroy(struct radeon_i2c_chan *i2c)
{
        if (!i2c)
                return;

        i2c_del_adapter(&i2c->adapter);
        kfree(i2c);
}

struct drm_encoder *radeon_best_encoder(struct drm_connector *connector)
{
        return NULL;
}