zephyr/drivers/ps2/ps2_mchp_xec.c

262 lines
6.2 KiB
C

/*
* Copyright (c) 2019 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT microchip_xec_ps2
#include <errno.h>
#include <device.h>
#include <drivers/ps2.h>
#include <soc.h>
#include <logging/log.h>
#define LOG_LEVEL CONFIG_PS2_LOG_LEVEL
LOG_MODULE_REGISTER(ps2_mchp_xec);
/* in 50us units */
#define PS2_TIMEOUT 10000
struct ps2_xec_config {
PS2_Type *base;
u8_t girq_id;
u8_t girq_bit;
u8_t isr_nvic;
};
struct ps2_xec_data {
ps2_callback_t callback_isr;
struct k_sem tx_lock;
};
static int ps2_xec_configure(struct device *dev, ps2_callback_t callback_isr)
{
const struct ps2_xec_config *config = dev->config->config_info;
struct ps2_xec_data *data = dev->driver_data;
PS2_Type *base = config->base;
u8_t __attribute__((unused)) dummy;
if (!callback_isr) {
return -EINVAL;
}
data->callback_isr = callback_isr;
/* In case the self test for a PS2 device already finished and
* set the SOURCE bit to 1 we clear it before enabling the
* interrupts. Instances must be allocated before the BAT or
* the host may time out.
*/
MCHP_GIRQ_SRC(config->girq_id) = BIT(config->girq_bit);
dummy = base->TRX_BUFF;
base->STATUS = MCHP_PS2_STATUS_RW1C_MASK;
/* Enable FSM and init instance in rx mode*/
base->CTRL = MCHP_PS2_CTRL_EN_POS;
/* We enable the interrupts in the EC aggregator so that the
* result can be forwarded to the ARM NVIC
*/
MCHP_GIRQ_ENSET(config->girq_id) = BIT(config->girq_bit);
k_sem_give(&data->tx_lock);
return 0;
}
static int ps2_xec_write(struct device *dev, u8_t value)
{
const struct ps2_xec_config *config = dev->config->config_info;
struct ps2_xec_data *data = dev->driver_data;
PS2_Type *base = config->base;
int i = 0;
u8_t __attribute__((unused)) dummy;
if (k_sem_take(&data->tx_lock, K_NO_WAIT)) {
return -EACCES;
}
/* Allow the PS2 controller to complete a RX transaction. This
* is because the channel may be actively receiving data.
* In addition, it is necessary to wait for a previous TX
* transaction to complete. The PS2 block has a single
* FSM.
*/
while (((base->STATUS &
(MCHP_PS2_STATUS_RXD_RDY | MCHP_PS2_STATUS_TX_IDLE))
!= MCHP_PS2_STATUS_TX_IDLE) && (i < PS2_TIMEOUT)) {
k_busy_wait(50);
i++;
}
if (unlikely(i == PS2_TIMEOUT)) {
LOG_DBG("PS2 write timed out");
return -ETIMEDOUT;
}
/* Inhibit ps2 controller and clear status register */
base->CTRL = 0x00;
/* Read to clear data ready bit in the status register*/
dummy = base->TRX_BUFF;
base->STATUS = MCHP_PS2_STATUS_RW1C_MASK;
/* Switch the interface to TX mode and enable state machine */
base->CTRL = MCHP_PS2_CTRL_TR_TX | MCHP_PS2_CTRL_EN;
/* Write value to TX/RX register */
base->TRX_BUFF = value;
k_sem_give(&data->tx_lock);
return 0;
}
static int ps2_xec_inhibit_interface(struct device *dev)
{
const struct ps2_xec_config *config = dev->config->config_info;
struct ps2_xec_data *data = dev->driver_data;
PS2_Type *base = config->base;
if (k_sem_take(&data->tx_lock, K_MSEC(10)) != 0) {
return -EACCES;
}
base->CTRL = 0x00;
MCHP_GIRQ_SRC(config->girq_id) = BIT(config->girq_bit);
NVIC_ClearPendingIRQ(config->isr_nvic);
k_sem_give(&data->tx_lock);
return 0;
}
static int ps2_xec_enable_interface(struct device *dev)
{
const struct ps2_xec_config *config = dev->config->config_info;
struct ps2_xec_data *data = dev->driver_data;
PS2_Type *base = config->base;
MCHP_GIRQ_SRC(config->girq_id) = BIT(config->girq_bit);
base->CTRL = MCHP_PS2_CTRL_EN;
k_sem_give(&data->tx_lock);
return 0;
}
static void ps2_xec_isr(void *arg)
{
struct device *dev = (struct device *)arg;
const struct ps2_xec_config *config = dev->config->config_info;
struct ps2_xec_data *data = dev->driver_data;
PS2_Type *base = config->base;
u32_t status;
MCHP_GIRQ_SRC(config->girq_id) = BIT(config->girq_bit);
/* Read and clear status */
status = base->STATUS;
if (status & MCHP_PS2_STATUS_RXD_RDY) {
base->CTRL = 0x00;
if (data->callback_isr) {
data->callback_isr(dev, base->TRX_BUFF);
}
} else if (status &
(MCHP_PS2_STATUS_TX_TMOUT | MCHP_PS2_STATUS_TX_ST_TMOUT)) {
/* Clear sticky bits and go to read mode */
base->STATUS = MCHP_PS2_STATUS_RW1C_MASK;
LOG_ERR("TX time out");
}
/* The control register reverts to RX automatically after
* transmiting the data
*/
base->CTRL = MCHP_PS2_CTRL_EN;
}
static const struct ps2_driver_api ps2_xec_driver_api = {
.config = ps2_xec_configure,
.read = NULL,
.write = ps2_xec_write,
.disable_callback = ps2_xec_inhibit_interface,
.enable_callback = ps2_xec_enable_interface,
};
#ifdef CONFIG_PS2_XEC_0
static int ps2_xec_init_0(struct device *dev);
static const struct ps2_xec_config ps2_xec_config_0 = {
.base = (PS2_Type *) DT_INST_REG_ADDR(0),
.girq_id = DT_INST_PROP(0, girq),
.girq_bit = DT_INST_PROP(0, girq_bit),
.isr_nvic = DT_INST_IRQN(0),
};
static struct ps2_xec_data ps2_xec_port_data_0;
DEVICE_AND_API_INIT(ps2_xec_0, DT_INST_LABEL(0),
&ps2_xec_init_0,
&ps2_xec_port_data_0, &ps2_xec_config_0,
POST_KERNEL, CONFIG_PS2_INIT_PRIORITY,
&ps2_xec_driver_api);
static int ps2_xec_init_0(struct device *dev)
{
ARG_UNUSED(dev);
struct ps2_xec_data *data = dev->driver_data;
k_sem_init(&data->tx_lock, 0, 1);
IRQ_CONNECT(DT_INST_IRQN(0),
DT_INST_IRQ(0, priority),
ps2_xec_isr, DEVICE_GET(ps2_xec_0), 0);
irq_enable(DT_INST_IRQN(0));
return 0;
}
#endif /* CONFIG_PS2_XEC_0 */
#ifdef CONFIG_PS2_XEC_1
static int ps2_xec_init_1(struct device *dev);
static const struct ps2_xec_config ps2_xec_config_1 = {
.base = (PS2_Type *) DT_INST_REG_ADDR(1),
.girq_id = DT_INST_PROP(1, girq),
.girq_bit = DT_INST_PROP(1, girq_bit),
.isr_nvic = DT_INST_IRQN(1),
};
static struct ps2_xec_data ps2_xec_port_data_1;
DEVICE_AND_API_INIT(ps2_xec_1, DT_INST_LABEL(1),
&ps2_xec_init_1,
&ps2_xec_port_data_1, &ps2_xec_config_1,
POST_KERNEL, CONFIG_PS2_INIT_PRIORITY,
&ps2_xec_driver_api);
static int ps2_xec_init_1(struct device *dev)
{
ARG_UNUSED(dev);
struct ps2_xec_data *data = dev->driver_data;
k_sem_init(&data->tx_lock, 0, 1);
IRQ_CONNECT(DT_INST_IRQN(1),
DT_INST_IRQ(1, priority),
ps2_xec_isr, DEVICE_GET(ps2_xec_1), 0);
irq_enable(DT_INST_IRQN(1));
return 0;
}
#endif /* CONFIG_PS2_XEC_1 */