diff options
Diffstat (limited to 'drivers/net/can/m_can/tcan4x5x.c')
| -rw-r--r-- | drivers/net/can/m_can/tcan4x5x.c | 540 |
1 files changed, 540 insertions, 0 deletions
diff --git a/drivers/net/can/m_can/tcan4x5x.c b/drivers/net/can/m_can/tcan4x5x.c new file mode 100644 index 000000000..f903f78af --- /dev/null +++ b/drivers/net/can/m_can/tcan4x5x.c @@ -0,0 +1,540 @@ +// SPDX-License-Identifier: GPL-2.0 +// SPI to CAN driver for the Texas Instruments TCAN4x5x +// Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/ + +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +#include <linux/regulator/consumer.h> +#include <linux/gpio/consumer.h> + +#include "m_can.h" + +#define DEVICE_NAME "tcan4x5x" +#define TCAN4X5X_EXT_CLK_DEF 40000000 + +#define TCAN4X5X_DEV_ID0 0x00 +#define TCAN4X5X_DEV_ID1 0x04 +#define TCAN4X5X_REV 0x08 +#define TCAN4X5X_STATUS 0x0C +#define TCAN4X5X_ERROR_STATUS 0x10 +#define TCAN4X5X_CONTROL 0x14 + +#define TCAN4X5X_CONFIG 0x800 +#define TCAN4X5X_TS_PRESCALE 0x804 +#define TCAN4X5X_TEST_REG 0x808 +#define TCAN4X5X_INT_FLAGS 0x820 +#define TCAN4X5X_MCAN_INT_REG 0x824 +#define TCAN4X5X_INT_EN 0x830 + +/* Interrupt bits */ +#define TCAN4X5X_CANBUSTERMOPEN_INT_EN BIT(30) +#define TCAN4X5X_CANHCANL_INT_EN BIT(29) +#define TCAN4X5X_CANHBAT_INT_EN BIT(28) +#define TCAN4X5X_CANLGND_INT_EN BIT(27) +#define TCAN4X5X_CANBUSOPEN_INT_EN BIT(26) +#define TCAN4X5X_CANBUSGND_INT_EN BIT(25) +#define TCAN4X5X_CANBUSBAT_INT_EN BIT(24) +#define TCAN4X5X_UVSUP_INT_EN BIT(22) +#define TCAN4X5X_UVIO_INT_EN BIT(21) +#define TCAN4X5X_TSD_INT_EN BIT(19) +#define TCAN4X5X_ECCERR_INT_EN BIT(16) +#define TCAN4X5X_CANINT_INT_EN BIT(15) +#define TCAN4X5X_LWU_INT_EN BIT(14) +#define TCAN4X5X_CANSLNT_INT_EN BIT(10) +#define TCAN4X5X_CANDOM_INT_EN BIT(8) +#define TCAN4X5X_CANBUS_ERR_INT_EN BIT(5) +#define TCAN4X5X_BUS_FAULT BIT(4) +#define TCAN4X5X_MCAN_INT BIT(1) +#define TCAN4X5X_ENABLE_TCAN_INT \ + (TCAN4X5X_MCAN_INT | TCAN4X5X_BUS_FAULT | \ + TCAN4X5X_CANBUS_ERR_INT_EN | TCAN4X5X_CANINT_INT_EN) + +/* MCAN Interrupt bits */ +#define TCAN4X5X_MCAN_IR_ARA BIT(29) +#define TCAN4X5X_MCAN_IR_PED BIT(28) +#define TCAN4X5X_MCAN_IR_PEA BIT(27) +#define TCAN4X5X_MCAN_IR_WD BIT(26) +#define TCAN4X5X_MCAN_IR_BO BIT(25) +#define TCAN4X5X_MCAN_IR_EW BIT(24) +#define TCAN4X5X_MCAN_IR_EP BIT(23) +#define TCAN4X5X_MCAN_IR_ELO BIT(22) +#define TCAN4X5X_MCAN_IR_BEU BIT(21) +#define TCAN4X5X_MCAN_IR_BEC BIT(20) +#define TCAN4X5X_MCAN_IR_DRX BIT(19) +#define TCAN4X5X_MCAN_IR_TOO BIT(18) +#define TCAN4X5X_MCAN_IR_MRAF BIT(17) +#define TCAN4X5X_MCAN_IR_TSW BIT(16) +#define TCAN4X5X_MCAN_IR_TEFL BIT(15) +#define TCAN4X5X_MCAN_IR_TEFF BIT(14) +#define TCAN4X5X_MCAN_IR_TEFW BIT(13) +#define TCAN4X5X_MCAN_IR_TEFN BIT(12) +#define TCAN4X5X_MCAN_IR_TFE BIT(11) +#define TCAN4X5X_MCAN_IR_TCF BIT(10) +#define TCAN4X5X_MCAN_IR_TC BIT(9) +#define TCAN4X5X_MCAN_IR_HPM BIT(8) +#define TCAN4X5X_MCAN_IR_RF1L BIT(7) +#define TCAN4X5X_MCAN_IR_RF1F BIT(6) +#define TCAN4X5X_MCAN_IR_RF1W BIT(5) +#define TCAN4X5X_MCAN_IR_RF1N BIT(4) +#define TCAN4X5X_MCAN_IR_RF0L BIT(3) +#define TCAN4X5X_MCAN_IR_RF0F BIT(2) +#define TCAN4X5X_MCAN_IR_RF0W BIT(1) +#define TCAN4X5X_MCAN_IR_RF0N BIT(0) +#define TCAN4X5X_ENABLE_MCAN_INT \ + (TCAN4X5X_MCAN_IR_TC | TCAN4X5X_MCAN_IR_RF0N | \ + TCAN4X5X_MCAN_IR_RF1N | TCAN4X5X_MCAN_IR_RF0F | \ + TCAN4X5X_MCAN_IR_RF1F) + +#define TCAN4X5X_MRAM_START 0x8000 +#define TCAN4X5X_MCAN_OFFSET 0x1000 +#define TCAN4X5X_MAX_REGISTER 0x8ffc + +#define TCAN4X5X_CLEAR_ALL_INT 0xffffffff +#define TCAN4X5X_SET_ALL_INT 0xffffffff + +#define TCAN4X5X_WRITE_CMD (0x61 << 24) +#define TCAN4X5X_READ_CMD (0x41 << 24) + +#define TCAN4X5X_MODE_SEL_MASK (BIT(7) | BIT(6)) +#define TCAN4X5X_MODE_SLEEP 0x00 +#define TCAN4X5X_MODE_STANDBY BIT(6) +#define TCAN4X5X_MODE_NORMAL BIT(7) + +#define TCAN4X5X_DISABLE_WAKE_MSK (BIT(31) | BIT(30)) +#define TCAN4X5X_DISABLE_INH_MSK BIT(9) + +#define TCAN4X5X_SW_RESET BIT(2) + +#define TCAN4X5X_MCAN_CONFIGURED BIT(5) +#define TCAN4X5X_WATCHDOG_EN BIT(3) +#define TCAN4X5X_WD_60_MS_TIMER 0 +#define TCAN4X5X_WD_600_MS_TIMER BIT(28) +#define TCAN4X5X_WD_3_S_TIMER BIT(29) +#define TCAN4X5X_WD_6_S_TIMER (BIT(28) | BIT(29)) + +struct tcan4x5x_priv { + struct regmap *regmap; + struct spi_device *spi; + + struct m_can_classdev *mcan_dev; + + struct gpio_desc *reset_gpio; + struct gpio_desc *device_wake_gpio; + struct gpio_desc *device_state_gpio; + struct regulator *power; + + /* Register based ip */ + int mram_start; + int reg_offset; +}; + +static void tcan4x5x_check_wake(struct tcan4x5x_priv *priv) +{ + int wake_state = 0; + + if (priv->device_state_gpio) + wake_state = gpiod_get_value(priv->device_state_gpio); + + if (priv->device_wake_gpio && wake_state) { + gpiod_set_value(priv->device_wake_gpio, 0); + usleep_range(5, 50); + gpiod_set_value(priv->device_wake_gpio, 1); + } +} + +static int tcan4x5x_reset(struct tcan4x5x_priv *priv) +{ + int ret = 0; + + if (priv->reset_gpio) { + gpiod_set_value(priv->reset_gpio, 1); + + /* tpulse_width minimum 30us */ + usleep_range(30, 100); + gpiod_set_value(priv->reset_gpio, 0); + } else { + ret = regmap_write(priv->regmap, TCAN4X5X_CONFIG, + TCAN4X5X_SW_RESET); + if (ret) + return ret; + } + + usleep_range(700, 1000); + + return ret; +} + +static int regmap_spi_gather_write(void *context, const void *reg, + size_t reg_len, const void *val, + size_t val_len) +{ + struct device *dev = context; + struct spi_device *spi = to_spi_device(dev); + struct spi_message m; + u32 addr; + struct spi_transfer t[2] = { + { .tx_buf = &addr, .len = reg_len, .cs_change = 0,}, + { .tx_buf = val, .len = val_len, }, + }; + + addr = TCAN4X5X_WRITE_CMD | (*((u16 *)reg) << 8) | val_len >> 2; + + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + + return spi_sync(spi, &m); +} + +static int tcan4x5x_regmap_write(void *context, const void *data, size_t count) +{ + u16 *reg = (u16 *)(data); + const u32 *val = data + 4; + + return regmap_spi_gather_write(context, reg, 4, val, count - 4); +} + +static int regmap_spi_async_write(void *context, + const void *reg, size_t reg_len, + const void *val, size_t val_len, + struct regmap_async *a) +{ + return -ENOTSUPP; +} + +static struct regmap_async *regmap_spi_async_alloc(void) +{ + return NULL; +} + +static int tcan4x5x_regmap_read(void *context, + const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct device *dev = context; + struct spi_device *spi = to_spi_device(dev); + + u32 addr = TCAN4X5X_READ_CMD | (*((u16 *)reg) << 8) | val_size >> 2; + + return spi_write_then_read(spi, &addr, reg_size, (u32 *)val, val_size); +} + +static struct regmap_bus tcan4x5x_bus = { + .write = tcan4x5x_regmap_write, + .gather_write = regmap_spi_gather_write, + .async_write = regmap_spi_async_write, + .async_alloc = regmap_spi_async_alloc, + .read = tcan4x5x_regmap_read, + .read_flag_mask = 0x00, + .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, + .val_format_endian_default = REGMAP_ENDIAN_NATIVE, +}; + +static u32 tcan4x5x_read_reg(struct m_can_classdev *cdev, int reg) +{ + struct tcan4x5x_priv *priv = cdev->device_data; + u32 val; + + regmap_read(priv->regmap, priv->reg_offset + reg, &val); + + return val; +} + +static u32 tcan4x5x_read_fifo(struct m_can_classdev *cdev, int addr_offset) +{ + struct tcan4x5x_priv *priv = cdev->device_data; + u32 val; + + regmap_read(priv->regmap, priv->mram_start + addr_offset, &val); + + return val; +} + +static int tcan4x5x_write_reg(struct m_can_classdev *cdev, int reg, int val) +{ + struct tcan4x5x_priv *priv = cdev->device_data; + + return regmap_write(priv->regmap, priv->reg_offset + reg, val); +} + +static int tcan4x5x_write_fifo(struct m_can_classdev *cdev, + int addr_offset, int val) +{ + struct tcan4x5x_priv *priv = cdev->device_data; + + return regmap_write(priv->regmap, priv->mram_start + addr_offset, val); +} + +static int tcan4x5x_power_enable(struct regulator *reg, int enable) +{ + if (IS_ERR_OR_NULL(reg)) + return 0; + + if (enable) + return regulator_enable(reg); + else + return regulator_disable(reg); +} + +static int tcan4x5x_write_tcan_reg(struct m_can_classdev *cdev, + int reg, int val) +{ + struct tcan4x5x_priv *priv = cdev->device_data; + + return regmap_write(priv->regmap, reg, val); +} + +static int tcan4x5x_clear_interrupts(struct m_can_classdev *cdev) +{ + int ret; + + ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_STATUS, + TCAN4X5X_CLEAR_ALL_INT); + if (ret) + return ret; + + ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_INT_FLAGS, + TCAN4X5X_CLEAR_ALL_INT); + if (ret) + return ret; + + ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_ERROR_STATUS, + TCAN4X5X_CLEAR_ALL_INT); + if (ret) + return ret; + + return ret; +} + +static int tcan4x5x_init(struct m_can_classdev *cdev) +{ + struct tcan4x5x_priv *tcan4x5x = cdev->device_data; + int ret; + + tcan4x5x_check_wake(tcan4x5x); + + ret = tcan4x5x_clear_interrupts(cdev); + if (ret) + return ret; + + ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_INT_EN, + TCAN4X5X_ENABLE_TCAN_INT); + if (ret) + return ret; + + /* Zero out the MCAN buffers */ + m_can_init_ram(cdev); + + ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, + TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL); + if (ret) + return ret; + + return ret; +} + +static int tcan4x5x_disable_wake(struct m_can_classdev *cdev) +{ + struct tcan4x5x_priv *tcan4x5x = cdev->device_data; + + return regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, + TCAN4X5X_DISABLE_WAKE_MSK, 0x00); +} + +static int tcan4x5x_disable_state(struct m_can_classdev *cdev) +{ + struct tcan4x5x_priv *tcan4x5x = cdev->device_data; + + return regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, + TCAN4X5X_DISABLE_INH_MSK, 0x01); +} + +static int tcan4x5x_parse_config(struct m_can_classdev *cdev) +{ + struct tcan4x5x_priv *tcan4x5x = cdev->device_data; + int ret; + + tcan4x5x->device_wake_gpio = devm_gpiod_get(cdev->dev, "device-wake", + GPIOD_OUT_HIGH); + if (IS_ERR(tcan4x5x->device_wake_gpio)) { + if (PTR_ERR(tcan4x5x->device_wake_gpio) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + tcan4x5x_disable_wake(cdev); + } + + tcan4x5x->reset_gpio = devm_gpiod_get_optional(cdev->dev, "reset", + GPIOD_OUT_LOW); + if (IS_ERR(tcan4x5x->reset_gpio)) + tcan4x5x->reset_gpio = NULL; + + ret = tcan4x5x_reset(tcan4x5x); + if (ret) + return ret; + + tcan4x5x->device_state_gpio = devm_gpiod_get_optional(cdev->dev, + "device-state", + GPIOD_IN); + if (IS_ERR(tcan4x5x->device_state_gpio)) { + tcan4x5x->device_state_gpio = NULL; + tcan4x5x_disable_state(cdev); + } + + return 0; +} + +static const struct regmap_config tcan4x5x_regmap = { + .reg_bits = 32, + .val_bits = 32, + .cache_type = REGCACHE_NONE, + .max_register = TCAN4X5X_MAX_REGISTER, +}; + +static struct m_can_ops tcan4x5x_ops = { + .init = tcan4x5x_init, + .read_reg = tcan4x5x_read_reg, + .write_reg = tcan4x5x_write_reg, + .write_fifo = tcan4x5x_write_fifo, + .read_fifo = tcan4x5x_read_fifo, + .clear_interrupts = tcan4x5x_clear_interrupts, +}; + +static int tcan4x5x_can_probe(struct spi_device *spi) +{ + struct tcan4x5x_priv *priv; + struct m_can_classdev *mcan_class; + int freq, ret; + + mcan_class = m_can_class_allocate_dev(&spi->dev); + if (!mcan_class) + return -ENOMEM; + + priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) { + ret = -ENOMEM; + goto out_m_can_class_free_dev; + } + + priv->power = devm_regulator_get_optional(&spi->dev, "vsup"); + if (PTR_ERR(priv->power) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto out_m_can_class_free_dev; + } else { + priv->power = NULL; + } + + mcan_class->device_data = priv; + + m_can_class_get_clocks(mcan_class); + if (IS_ERR(mcan_class->cclk)) { + dev_err(&spi->dev, "no CAN clock source defined\n"); + freq = TCAN4X5X_EXT_CLK_DEF; + } else { + freq = clk_get_rate(mcan_class->cclk); + } + + /* Sanity check */ + if (freq < 20000000 || freq > TCAN4X5X_EXT_CLK_DEF) { + ret = -ERANGE; + goto out_m_can_class_free_dev; + } + + priv->reg_offset = TCAN4X5X_MCAN_OFFSET; + priv->mram_start = TCAN4X5X_MRAM_START; + priv->spi = spi; + priv->mcan_dev = mcan_class; + + mcan_class->pm_clock_support = 0; + mcan_class->can.clock.freq = freq; + mcan_class->dev = &spi->dev; + mcan_class->ops = &tcan4x5x_ops; + mcan_class->is_peripheral = true; + mcan_class->net->irq = spi->irq; + + spi_set_drvdata(spi, priv); + + /* Configure the SPI bus */ + spi->bits_per_word = 32; + ret = spi_setup(spi); + if (ret) + goto out_m_can_class_free_dev; + + priv->regmap = devm_regmap_init(&spi->dev, &tcan4x5x_bus, + &spi->dev, &tcan4x5x_regmap); + if (IS_ERR(priv->regmap)) { + ret = PTR_ERR(priv->regmap); + goto out_m_can_class_free_dev; + } + + ret = tcan4x5x_power_enable(priv->power, 1); + if (ret) + goto out_m_can_class_free_dev; + + ret = tcan4x5x_parse_config(mcan_class); + if (ret) + goto out_power; + + ret = tcan4x5x_init(mcan_class); + if (ret) + goto out_power; + + ret = m_can_class_register(mcan_class); + if (ret) + goto out_power; + + netdev_info(mcan_class->net, "TCAN4X5X successfully initialized.\n"); + return 0; + +out_power: + tcan4x5x_power_enable(priv->power, 0); + out_m_can_class_free_dev: + m_can_class_free_dev(mcan_class->net); + dev_err(&spi->dev, "Probe failed, err=%d\n", ret); + + return ret; +} + +static int tcan4x5x_can_remove(struct spi_device *spi) +{ + struct tcan4x5x_priv *priv = spi_get_drvdata(spi); + + m_can_class_unregister(priv->mcan_dev); + + tcan4x5x_power_enable(priv->power, 0); + + m_can_class_free_dev(priv->mcan_dev->net); + + return 0; +} + +static const struct of_device_id tcan4x5x_of_match[] = { + { .compatible = "ti,tcan4x5x", }, + { } +}; +MODULE_DEVICE_TABLE(of, tcan4x5x_of_match); + +static const struct spi_device_id tcan4x5x_id_table[] = { + { + .name = "tcan4x5x", + .driver_data = 0, + }, + { } +}; +MODULE_DEVICE_TABLE(spi, tcan4x5x_id_table); + +static struct spi_driver tcan4x5x_can_driver = { + .driver = { + .name = DEVICE_NAME, + .of_match_table = tcan4x5x_of_match, + .pm = NULL, + }, + .id_table = tcan4x5x_id_table, + .probe = tcan4x5x_can_probe, + .remove = tcan4x5x_can_remove, +}; +module_spi_driver(tcan4x5x_can_driver); + +MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); +MODULE_DESCRIPTION("Texas Instruments TCAN4x5x CAN driver"); +MODULE_LICENSE("GPL v2"); |