kernel/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c
2024-07-22 17:22:30 +08:00

350 lines
9.7 KiB
C

/*
* adv7511_cec.c - Analog Devices ADV7511/33 cec driver
*
* Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* 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 AUTHORS OR COPYRIGHT HOLDERS
* 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.
*
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <media/cec.h>
#include "adv7511.h"
#define ADV7511_INT1_CEC_MASK \
(ADV7511_INT1_CEC_TX_READY | ADV7511_INT1_CEC_TX_ARBIT_LOST | \
ADV7511_INT1_CEC_TX_RETRY_TIMEOUT | ADV7511_INT1_CEC_RX_READY1)
static void adv_cec_tx_raw_status(struct adv7511 *adv7511, u8 tx_raw_status)
{
unsigned int offset = adv7511->type == ADV7533 ?
ADV7533_REG_CEC_OFFSET : 0;
unsigned int val;
if (regmap_read(adv7511->regmap_cec,
ADV7511_REG_CEC_TX_ENABLE + offset, &val))
return;
if ((val & 0x01) == 0)
return;
if (tx_raw_status & ADV7511_INT1_CEC_TX_ARBIT_LOST) {
cec_transmit_attempt_done(adv7511->cec_adap,
CEC_TX_STATUS_ARB_LOST);
return;
}
if (tx_raw_status & ADV7511_INT1_CEC_TX_RETRY_TIMEOUT) {
u8 status;
u8 err_cnt = 0;
u8 nack_cnt = 0;
u8 low_drive_cnt = 0;
unsigned int cnt;
/*
* We set this status bit since this hardware performs
* retransmissions.
*/
status = CEC_TX_STATUS_MAX_RETRIES;
if (regmap_read(adv7511->regmap_cec,
ADV7511_REG_CEC_TX_LOW_DRV_CNT + offset, &cnt)) {
err_cnt = 1;
status |= CEC_TX_STATUS_ERROR;
} else {
nack_cnt = cnt & 0xf;
if (nack_cnt)
status |= CEC_TX_STATUS_NACK;
low_drive_cnt = cnt >> 4;
if (low_drive_cnt)
status |= CEC_TX_STATUS_LOW_DRIVE;
}
cec_transmit_done(adv7511->cec_adap, status,
0, nack_cnt, low_drive_cnt, err_cnt);
return;
}
if (tx_raw_status & ADV7511_INT1_CEC_TX_READY) {
cec_transmit_attempt_done(adv7511->cec_adap, CEC_TX_STATUS_OK);
return;
}
}
void adv7511_cec_irq_process(struct adv7511 *adv7511, unsigned int irq1)
{
unsigned int offset = adv7511->type == ADV7533 ?
ADV7533_REG_CEC_OFFSET : 0;
const u32 irq_tx_mask = ADV7511_INT1_CEC_TX_READY |
ADV7511_INT1_CEC_TX_ARBIT_LOST |
ADV7511_INT1_CEC_TX_RETRY_TIMEOUT;
struct cec_msg msg = {};
unsigned int len;
unsigned int val;
u8 i;
if (irq1 & irq_tx_mask)
adv_cec_tx_raw_status(adv7511, irq1);
if (!(irq1 & ADV7511_INT1_CEC_RX_READY1))
return;
if (regmap_read(adv7511->regmap_cec,
ADV7511_REG_CEC_RX_FRAME_LEN + offset, &len))
return;
msg.len = len & 0x1f;
if (msg.len > 16)
msg.len = 16;
if (!msg.len)
return;
for (i = 0; i < msg.len; i++) {
regmap_read(adv7511->regmap_cec,
i + ADV7511_REG_CEC_RX_FRAME_HDR + offset, &val);
msg.msg[i] = val;
}
/* toggle to re-enable rx 1 */
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_RX_BUFFERS + offset, 1);
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_RX_BUFFERS + offset, 0);
cec_received_msg(adv7511->cec_adap, &msg);
}
static int adv7511_cec_adap_enable(struct cec_adapter *adap, bool enable)
{
struct adv7511 *adv7511 = cec_get_drvdata(adap);
unsigned int offset = adv7511->type == ADV7533 ?
ADV7533_REG_CEC_OFFSET : 0;
if (adv7511->i2c_cec == NULL)
return -EIO;
if (!adv7511->cec_enabled_adap && enable) {
/* power up cec section */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_CLK_DIV + offset,
0x03, 0x01);
/* legacy mode and clear all rx buffers */
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_RX_BUFFERS + offset, 0x07);
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_RX_BUFFERS + offset, 0);
/* initially disable tx */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_TX_ENABLE + offset, 1, 0);
/* enabled irqs: */
/* tx: ready */
/* tx: arbitration lost */
/* tx: retry timeout */
/* rx: ready 1 */
regmap_update_bits(adv7511->regmap,
ADV7511_REG_INT_ENABLE(1), 0x3f,
ADV7511_INT1_CEC_MASK);
} else if (adv7511->cec_enabled_adap && !enable) {
regmap_update_bits(adv7511->regmap,
ADV7511_REG_INT_ENABLE(1), 0x3f, 0);
/* disable address mask 1-3 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
0x70, 0x00);
/* power down cec section */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_CLK_DIV + offset,
0x03, 0x00);
adv7511->cec_valid_addrs = 0;
}
adv7511->cec_enabled_adap = enable;
return 0;
}
static int adv7511_cec_adap_log_addr(struct cec_adapter *adap, u8 addr)
{
struct adv7511 *adv7511 = cec_get_drvdata(adap);
unsigned int offset = adv7511->type == ADV7533 ?
ADV7533_REG_CEC_OFFSET : 0;
unsigned int i, free_idx = ADV7511_MAX_ADDRS;
if (!adv7511->cec_enabled_adap)
return addr == CEC_LOG_ADDR_INVALID ? 0 : -EIO;
if (addr == CEC_LOG_ADDR_INVALID) {
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
0x70, 0);
adv7511->cec_valid_addrs = 0;
return 0;
}
for (i = 0; i < ADV7511_MAX_ADDRS; i++) {
bool is_valid = adv7511->cec_valid_addrs & (1 << i);
if (free_idx == ADV7511_MAX_ADDRS && !is_valid)
free_idx = i;
if (is_valid && adv7511->cec_addr[i] == addr)
return 0;
}
if (i == ADV7511_MAX_ADDRS) {
i = free_idx;
if (i == ADV7511_MAX_ADDRS)
return -ENXIO;
}
adv7511->cec_addr[i] = addr;
adv7511->cec_valid_addrs |= 1 << i;
switch (i) {
case 0:
/* enable address mask 0 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
0x10, 0x10);
/* set address for mask 0 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_0_1 + offset,
0x0f, addr);
break;
case 1:
/* enable address mask 1 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
0x20, 0x20);
/* set address for mask 1 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_0_1 + offset,
0xf0, addr << 4);
break;
case 2:
/* enable address mask 2 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
0x40, 0x40);
/* set address for mask 1 */
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_LOG_ADDR_2 + offset,
0x0f, addr);
break;
}
return 0;
}
static int adv7511_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
u32 signal_free_time, struct cec_msg *msg)
{
struct adv7511 *adv7511 = cec_get_drvdata(adap);
unsigned int offset = adv7511->type == ADV7533 ?
ADV7533_REG_CEC_OFFSET : 0;
u8 len = msg->len;
unsigned int i;
/*
* The number of retries is the number of attempts - 1, but retry
* at least once. It's not clear if a value of 0 is allowed, so
* let's do at least one retry.
*/
regmap_update_bits(adv7511->regmap_cec,
ADV7511_REG_CEC_TX_RETRY + offset,
0x70, max(1, attempts - 1) << 4);
/* blocking, clear cec tx irq status */
regmap_update_bits(adv7511->regmap, ADV7511_REG_INT(1), 0x38, 0x38);
/* write data */
for (i = 0; i < len; i++)
regmap_write(adv7511->regmap_cec,
i + ADV7511_REG_CEC_TX_FRAME_HDR + offset,
msg->msg[i]);
/* set length (data + header) */
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_TX_FRAME_LEN + offset, len);
/* start transmit, enable tx */
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_TX_ENABLE + offset, 0x01);
return 0;
}
static const struct cec_adap_ops adv7511_cec_adap_ops = {
.adap_enable = adv7511_cec_adap_enable,
.adap_log_addr = adv7511_cec_adap_log_addr,
.adap_transmit = adv7511_cec_adap_transmit,
};
static int adv7511_cec_parse_dt(struct device *dev, struct adv7511 *adv7511)
{
adv7511->cec_clk = devm_clk_get(dev, "cec");
if (IS_ERR(adv7511->cec_clk)) {
int ret = PTR_ERR(adv7511->cec_clk);
adv7511->cec_clk = NULL;
return ret;
}
clk_prepare_enable(adv7511->cec_clk);
adv7511->cec_clk_freq = clk_get_rate(adv7511->cec_clk);
return 0;
}
int adv7511_cec_init(struct device *dev, struct adv7511 *adv7511)
{
unsigned int offset = adv7511->type == ADV7533 ?
ADV7533_REG_CEC_OFFSET : 0;
int ret = adv7511_cec_parse_dt(dev, adv7511);
if (ret)
goto err_cec_parse_dt;
adv7511->cec_adap = cec_allocate_adapter(&adv7511_cec_adap_ops,
adv7511, dev_name(dev), CEC_CAP_DEFAULTS, ADV7511_MAX_ADDRS);
if (IS_ERR(adv7511->cec_adap)) {
ret = PTR_ERR(adv7511->cec_adap);
goto err_cec_alloc;
}
regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL, 0);
/* cec soft reset */
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_SOFT_RESET + offset, 0x01);
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_SOFT_RESET + offset, 0x00);
/* legacy mode */
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_RX_BUFFERS + offset, 0x00);
regmap_write(adv7511->regmap_cec,
ADV7511_REG_CEC_CLK_DIV + offset,
((adv7511->cec_clk_freq / 750000) - 1) << 2);
ret = cec_register_adapter(adv7511->cec_adap, dev);
if (ret)
goto err_cec_register;
return 0;
err_cec_register:
cec_delete_adapter(adv7511->cec_adap);
adv7511->cec_adap = NULL;
err_cec_alloc:
dev_info(dev, "Initializing CEC failed with error %d, disabling CEC\n",
ret);
err_cec_parse_dt:
regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL,
ADV7511_CEC_CTRL_POWER_DOWN);
return ret == -EPROBE_DEFER ? ret : 0;
}