// 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 #include #include #include #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 0x8fff #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_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 struct can_bittiming_const tcan4x5x_bittiming_const = { .name = DEVICE_NAME, .tseg1_min = 2, .tseg1_max = 31, .tseg2_min = 2, .tseg2_max = 16, .sjw_max = 16, .brp_min = 1, .brp_max = 32, .brp_inc = 1, }; static struct can_bittiming_const tcan4x5x_data_bittiming_const = { .name = DEVICE_NAME, .tseg1_min = 1, .tseg1_max = 32, .tseg2_min = 1, .tseg2_max = 16, .sjw_max = 16, .brp_min = 1, .brp_max = 32, .brp_inc = 1, }; 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_MCAN_INT_REG, TCAN4X5X_ENABLE_MCAN_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; ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL); if (ret) return ret; /* Zero out the MCAN buffers */ m_can_init_ram(cdev); return ret; } 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)) { dev_err(cdev->dev, "device-wake gpio not defined\n"); return -EINVAL; } 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->power = devm_regulator_get_optional(cdev->dev, "vsup"); if (PTR_ERR(tcan4x5x->power) == -EPROBE_DEFER) return -EPROBE_DEFER; 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) return -ENOMEM; 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) return -ERANGE; 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->bit_timing = &tcan4x5x_bittiming_const; mcan_class->data_timing = &tcan4x5x_data_bittiming_const; mcan_class->net->irq = spi->irq; spi_set_drvdata(spi, priv); ret = tcan4x5x_parse_config(mcan_class); if (ret) goto out_clk; /* Configure the SPI bus */ spi->bits_per_word = 32; ret = spi_setup(spi); if (ret) goto out_clk; priv->regmap = devm_regmap_init(&spi->dev, &tcan4x5x_bus, &spi->dev, &tcan4x5x_regmap); tcan4x5x_power_enable(priv->power, 1); 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_clk: if (!IS_ERR(mcan_class->cclk)) { clk_disable_unprepare(mcan_class->cclk); clk_disable_unprepare(mcan_class->hclk); } 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); tcan4x5x_power_enable(priv->power, 0); m_can_class_unregister(priv->mcan_dev); 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 "); MODULE_DESCRIPTION("Texas Instruments TCAN4x5x CAN driver"); MODULE_LICENSE("GPL v2");