Atmosphere/fusee/fusee-secondary/src/i2c.c

253 lines
7.4 KiB
C

/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "i2c.h"
#include "utils.h"
#include "timers.h"
#include "pinmux.h"
/* Prototypes for internal commands. */
volatile tegra_i2c_t *i2c_get_registers_from_id(I2CDevice id);
void i2c_load_config(volatile tegra_i2c_t *regs);
bool i2c_query(I2CDevice id, uint8_t device, uint8_t r, void *dst, size_t dst_size);
bool i2c_send(I2CDevice id, uint8_t device, uint8_t r, void *src, size_t src_size);
bool i2c_write(volatile tegra_i2c_t *regs, uint8_t device, void *src, size_t src_size);
bool i2c_read(volatile tegra_i2c_t *regs, uint8_t device, void *dst, size_t dst_size);
/* Configure I2C pinmux. */
void i2c_config(I2CDevice id) {
volatile tegra_pinmux_t *pinmux = pinmux_get_regs();
switch (id) {
case I2C_1:
pinmux->gen1_i2c_scl = PINMUX_INPUT;
pinmux->gen1_i2c_sda = PINMUX_INPUT;
break;
case I2C_2:
pinmux->gen2_i2c_scl = PINMUX_INPUT;
pinmux->gen2_i2c_sda = PINMUX_INPUT;
break;
case I2C_3:
pinmux->gen3_i2c_scl = PINMUX_INPUT;
pinmux->gen3_i2c_sda = PINMUX_INPUT;
break;
case I2C_4:
pinmux->cam_i2c_scl = PINMUX_INPUT;
pinmux->cam_i2c_sda = PINMUX_INPUT;
break;
case I2C_5:
pinmux->pwr_i2c_scl = PINMUX_INPUT;
pinmux->pwr_i2c_sda = PINMUX_INPUT;
break;
case I2C_6:
/* Unused. */
break;
default: break;
}
}
/* Initialize I2C based on registers. */
void i2c_init(I2CDevice id) {
volatile tegra_i2c_t *regs = i2c_get_registers_from_id(id);
/* Setup divisor, and clear the bus. */
regs->I2C_I2C_CLK_DIVISOR_REGISTER_0 = 0x50001;
regs->I2C_I2C_BUS_CLEAR_CONFIG_0 = 0x90003;
/* Load hardware configuration. */
i2c_load_config(regs);
/* Wait a while until BUS_CLEAR_DONE is set. */
for (unsigned int i = 0; i < 10; i++) {
udelay(20000);
if (regs->I2C_INTERRUPT_STATUS_REGISTER_0 & 0x800) {
break;
}
}
/* Read the BUS_CLEAR_STATUS. Result doesn't matter. */
regs->I2C_I2C_BUS_CLEAR_STATUS_0;
/* Read and set the Interrupt Status. */
uint32_t int_status = regs->I2C_INTERRUPT_STATUS_REGISTER_0;
regs->I2C_INTERRUPT_STATUS_REGISTER_0 = int_status;
}
/* Sets a bit in a PMIC register over I2C during CPU shutdown. */
void i2c_send_pmic_cpu_shutdown_cmd(void) {
uint32_t val = 0;
/* PMIC == Device 4:3C. */
i2c_query(I2C_5, MAX77620_PWR_I2C_ADDR, 0x41, &val, 1);
val |= 4;
i2c_send(I2C_5, MAX77620_PWR_I2C_ADDR, 0x41, &val, 1);
}
/* Queries the value of TI charger bit over I2C. */
bool i2c_query_ti_charger_bit_7(void) {
uint32_t val = 0;
/* TI Charger = Device 0:6B. */
i2c_query(I2C_1, BQ24193_I2C_ADDR, 0, &val, 1);
return (val & 0x80) != 0;
}
/* Clears TI charger bit over I2C. */
void i2c_clear_ti_charger_bit_7(void) {
uint32_t val = 0;
/* TI Charger = Device 0:6B. */
i2c_query(I2C_1, BQ24193_I2C_ADDR, 0, &val, 1);
val &= 0x7F;
i2c_send(I2C_1, BQ24193_I2C_ADDR, 0, &val, 1);
}
/* Sets TI charger bit over I2C. */
void i2c_set_ti_charger_bit_7(void) {
uint32_t val = 0;
/* TI Charger = Device 0:6B. */
i2c_query(I2C_1, BQ24193_I2C_ADDR, 0, &val, 1);
val |= 0x80;
i2c_send(I2C_1, BQ24193_I2C_ADDR, 0, &val, 1);
}
/* Get registers pointer based on I2C ID. */
volatile tegra_i2c_t *i2c_get_registers_from_id(I2CDevice id) {
switch (id) {
case I2C_1:
return I2C1_REGS;
case I2C_2:
return I2C2_REGS;
case I2C_3:
return I2C3_REGS;
case I2C_4:
return I2C4_REGS;
case I2C_5:
return I2C5_REGS;
case I2C_6:
return I2C6_REGS;
default:
generic_panic();
}
return NULL;
}
/* Load hardware config for I2C4. */
void i2c_load_config(volatile tegra_i2c_t *regs) {
/* Set MSTR_CONFIG_LOAD, TIMEOUT_CONFIG_LOAD, undocumented bit. */
regs->I2C_I2C_CONFIG_LOAD_0 = 0x25;
/* Wait a bit for master config to be loaded. */
for (unsigned int i = 0; i < 20; i++) {
udelay(1);
if (!(regs->I2C_I2C_CONFIG_LOAD_0 & 1)) {
break;
}
}
}
/* Reads a register from a device over I2C, writes result to output. */
bool i2c_query(I2CDevice id, uint8_t device, uint8_t r, void *dst, size_t dst_size) {
volatile tegra_i2c_t *regs = i2c_get_registers_from_id(id);
uint32_t val = r;
/* Write single byte register ID to device. */
if (!i2c_write(regs, device, &val, 1)) {
return false;
}
/* Limit output size to 32-bits. */
if (dst_size > 4) {
return false;
}
return i2c_read(regs, device, dst, dst_size);
}
/* Writes a value to a register over I2C. */
bool i2c_send(I2CDevice id, uint8_t device, uint8_t r, void *src, size_t src_size) {
uint32_t val = r;
if (src_size == 0) {
return true;
} else if (src_size <= 3) {
memcpy(((uint8_t *)&val) + 1, src, src_size);
return i2c_write(i2c_get_registers_from_id(id), device, &val, src_size + 1);
} else {
return false;
}
}
/* Writes bytes to device over I2C. */
bool i2c_write(volatile tegra_i2c_t *regs, uint8_t device, void *src, size_t src_size) {
if (src_size > 4) {
return false;
} else if (src_size == 0) {
return true;
}
/* Set device for 7-bit write mode. */
regs->I2C_I2C_CMD_ADDR0_0 = device << 1;
/* Load in data to write. */
regs->I2C_I2C_CMD_DATA1_0 = read32le(src, 0);
/* Set config with LENGTH = src_size, NEW_MASTER_FSM, DEBOUNCE_CNT = 4T. */
regs->I2C_I2C_CNFG_0 = ((src_size << 1) - 2) | 0x2800;
i2c_load_config(regs);
/* Config |= SEND; */
regs->I2C_I2C_CNFG_0 = ((regs->I2C_I2C_CNFG_0 & 0xFFFFFDFF) | 0x200);
while (regs->I2C_I2C_STATUS_0 & 0x100) {
/* Wait until not busy. */
}
/* Return CMD1_STAT == SL1_XFER_SUCCESSFUL. */
return (regs->I2C_I2C_STATUS_0 & 0xF) == 0;
}
/* Reads bytes from device over I2C. */
bool i2c_read(volatile tegra_i2c_t *regs, uint8_t device, void *dst, size_t dst_size) {
if (dst_size > 4) {
return false;
} else if (dst_size == 0) {
return true;
}
/* Set device for 7-bit read mode. */
regs->I2C_I2C_CMD_ADDR0_0 = (device << 1) | 1;
/* Set config with LENGTH = dst_size, NEW_MASTER_FSM, DEBOUNCE_CNT = 4T. */
regs->I2C_I2C_CNFG_0 = ((dst_size << 1) - 2) | 0x2840;
i2c_load_config(regs);
/* Config |= SEND; */
regs->I2C_I2C_CNFG_0 = ((regs->I2C_I2C_CNFG_0 & 0xFFFFFDFF) | 0x200);
while (regs->I2C_I2C_STATUS_0 & 0x100) {
/* Wait until not busy. */
}
/* Ensure success. */
if ((regs->I2C_I2C_STATUS_0 & 0xF) != 0) {
return false;
}
uint32_t val = regs->I2C_I2C_CMD_DATA1_0;
memcpy(dst, &val, dst_size);
return true;
}