Add the TCAN4x5x SPI CAN driver. This device uses the Bosch MCAN IP core along with a SPI interface map. Leverage the MCAN common core code to manage the MCAN IP. This device has a special method to indicate a write/read operation on the data payload. Signed-off-by: Dan Murphy <dmurphy@xxxxxx> --- drivers/net/can/m_can/Kconfig | 6 + drivers/net/can/m_can/tcan4x5x.c | 321 +++++++++++++++++++++++++++++++ 2 files changed, 327 insertions(+) create mode 100644 drivers/net/can/m_can/tcan4x5x.c diff --git a/drivers/net/can/m_can/Kconfig b/drivers/net/can/m_can/Kconfig index b1a9358b7660..943e10e15f17 100644 --- a/drivers/net/can/m_can/Kconfig +++ b/drivers/net/can/m_can/Kconfig @@ -15,3 +15,9 @@ config CAN_M_CAN_PLATFORM tristate "Bosch M_CAN devices" ---help--- Say Y here if you want to support for Bosch M_CAN controller. + +config CAN_M_CAN_TCAN4X5X + depends on CAN_M_CAN_CORE + tristate "TCAN4X5X M_CAN device" + ---help--- + Say Y here if you want to support for TI M_CAN controller. diff --git a/drivers/net/can/m_can/tcan4x5x.c b/drivers/net/can/m_can/tcan4x5x.c new file mode 100644 index 000000000000..f55cfed2a33b --- /dev/null +++ b/drivers/net/can/m_can/tcan4x5x.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0 +// SPI to CAN driver for the Texas Instruments TCAN4x5x +// Copyright (C) 2018 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_platform.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 + +#define TCAN4X5X_MRAM_START 0x8000 + +#define TCAN4X5X_MAX_REGISTER 0x8fff + +#define TCAN4X5X_WRITE_CMD (0x61 << 24) +#define TCAN4X5X_READ_CMD (0x41 << 24) + +struct tcan4x5x_priv { + struct regmap *regmap; + struct spi_device *spi; + struct mutex tcan4x5x_lock; /* SPI device lock */ + + struct gpio_desc *reset_gpio; + struct gpio_desc *interrupt_gpio; + struct gpio_desc *wake_gpio; + struct regulator *power; +}; + +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); + u32 addr; + struct spi_message m; + struct spi_transfer t[2] = {{ .tx_buf = &addr, .len = 4, .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 + 2; + + return regmap_spi_gather_write(context, reg, 2, val, count - 2); +} + +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, 4, 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, +}; + +u32 tcan4x5x_read_reg(const struct m_can_classdev *m_can_class, int reg) +{ + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; + u32 val; + + regmap_read(priv->regmap, reg, &val); + + return val; +} + +u32 tcan4x5x_read_fifo(const struct m_can_classdev *m_can_class, int reg) +{ + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; + u32 val; + + regmap_read(priv->regmap, reg, &val); + + return val; +} + +int tcan4x5x_write_reg(const struct m_can_classdev *m_can_class, int reg, int val) +{ + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; + + return regmap_write(priv->regmap, reg, val); +} + +int tcan4x5x_write_fifo(const struct m_can_classdev *m_can_class, int reg, int val) +{ + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; + + return regmap_write(priv->regmap, reg, 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_init(struct m_can_classdev *class_dev) +{ + /* Zero out the MCAN buffers */ + m_can_init_ram(class_dev); + + return 0; +} + +static int tcan4x5x_parse_config(struct m_can_classdev *class_dev) +{ + struct tcan4x5x_priv *tcan4x5x = (struct tcan4x5x_priv *)class_dev->device_data; + + tcan4x5x->reset_gpio = devm_gpiod_get_optional(class_dev->dev, + "reset", GPIOD_OUT_LOW); + if (IS_ERR(tcan4x5x->reset_gpio)) + tcan4x5x->reset_gpio = NULL; + + tcan4x5x->wake_gpio = devm_gpiod_get_optional(class_dev->dev, + "wake-up", GPIOD_OUT_LOW); + if (IS_ERR(tcan4x5x->wake_gpio)) + tcan4x5x->wake_gpio = NULL; + + tcan4x5x->interrupt_gpio = devm_gpiod_get(class_dev->dev, + "data-ready", GPIOD_IN); + if (IS_ERR(tcan4x5x->interrupt_gpio)) { + dev_err(class_dev->dev, "data-ready gpio not defined\n"); + return -EINVAL; + } + + class_dev->net->irq = gpiod_to_irq(tcan4x5x->interrupt_gpio); + + tcan4x5x->power = devm_regulator_get_optional(class_dev->dev, + "vsup"); + if (PTR_ERR(tcan4x5x->power) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + return 0; +} + +static const struct regmap_config tcan4x5x_regmap = { + .reg_bits = 16, + .val_bits = 32, + .cache_type = REGCACHE_NONE, + .max_register = TCAN4X5X_MAX_REGISTER, +}; + +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_core_allocate_dev(&spi->dev); + priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + mcan_class->device_data = priv; + + m_can_core_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; + + mcan_class->reg_offset = 0x1000; + mcan_class->pm_clock_support = 0; + mcan_class->mram_start = TCAN4X5X_MRAM_START; + mcan_class->m_can_read = &tcan4x5x_read_reg; + mcan_class->m_can_write = &tcan4x5x_write_reg; + mcan_class->m_can_fifo_write = &tcan4x5x_write_fifo; + mcan_class->m_can_fifo_read = &tcan4x5x_read_fifo; + + mcan_class->can.clock.freq = freq; + + mcan_class->dev = &spi->dev; + 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_init(mcan_class); + + m_can_core_register(mcan_class); + + mutex_init(&priv->tcan4x5x_lock); + + netdev_info(mcan_class->net, "TCAN4X5X successfully initialized.\n"); + return 0; + +out_clk: + if (!IS_ERR(mcan_class->cclk)) { + clk_disable_unprepare(mcan_class->cclk); + clk_disable_unprepare(mcan_class->hclk); + } + + free_candev(mcan_class->net); + dev_err(&spi->dev, "Probe failed, err=%d\n", -ret); + return ret; +} + +static int tcan4x5x_can_remove(struct spi_device *spi) +{ +#if 0 + struct tcan4x5x_priv *priv = spi_get_drvdata(spi); + struct net_device *net = mcan_class->net; + + unregister_candev(net); + + tcan4x5x_power_enable(priv->power, 0); + + if (!IS_ERR(mcan_class->cclk)) + clk_disable_unprepare(mcan_class->cclk); + + free_candev(net); +#endif + 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@xxxxxx>"); +MODULE_DESCRIPTION("Texas Instruments TCAN4x5x CAN driver"); +MODULE_LICENSE("GPL v2"); -- 2.20.0.rc2.7.g965798d1f2