// SPDX-License-Identifier: GPL-2.0 // // mcp251xfd - Microchip MCP251xFD Family CAN controller driver // // Copyright (c) 2019, 2020, 2021 Pengutronix, // Marc Kleine-Budde // // Based on: // // CAN bus driver for Microchip 25XXFD CAN Controller with SPI Interface // // Copyright (c) 2019 Martin Sperl // #include #include #include #include #include #include #include #include "mcp251xfd.h" #define DEVICE_NAME "mcp251xfd" static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp2517fd = { .quirks = MCP251XFD_QUIRK_MAB_NO_WARN | MCP251XFD_QUIRK_CRC_REG | MCP251XFD_QUIRK_CRC_RX | MCP251XFD_QUIRK_CRC_TX | MCP251XFD_QUIRK_ECC, .model = MCP251XFD_MODEL_MCP2517FD, }; static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp2518fd = { .quirks = MCP251XFD_QUIRK_CRC_REG | MCP251XFD_QUIRK_CRC_RX | MCP251XFD_QUIRK_CRC_TX | MCP251XFD_QUIRK_ECC, .model = MCP251XFD_MODEL_MCP2518FD, }; static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp251863 = { .quirks = MCP251XFD_QUIRK_CRC_REG | MCP251XFD_QUIRK_CRC_RX | MCP251XFD_QUIRK_CRC_TX | MCP251XFD_QUIRK_ECC, .model = MCP251XFD_MODEL_MCP251863, }; /* Autodetect model, start with CRC enabled. */ static const struct mcp251xfd_devtype_data mcp251xfd_devtype_data_mcp251xfd = { .quirks = MCP251XFD_QUIRK_CRC_REG | MCP251XFD_QUIRK_CRC_RX | MCP251XFD_QUIRK_CRC_TX | MCP251XFD_QUIRK_ECC, .model = MCP251XFD_MODEL_MCP251XFD, }; static const struct can_bittiming_const mcp251xfd_bittiming_const = { .name = DEVICE_NAME, .tseg1_min = 2, .tseg1_max = 256, .tseg2_min = 1, .tseg2_max = 128, .sjw_max = 128, .brp_min = 1, .brp_max = 256, .brp_inc = 1, }; static const struct can_bittiming_const mcp251xfd_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 = 256, .brp_inc = 1, }; static const char *__mcp251xfd_get_model_str(enum mcp251xfd_model model) { switch (model) { case MCP251XFD_MODEL_MCP2517FD: return "MCP2517FD"; case MCP251XFD_MODEL_MCP2518FD: return "MCP2518FD"; case MCP251XFD_MODEL_MCP251863: return "MCP251863"; case MCP251XFD_MODEL_MCP251XFD: return "MCP251xFD"; } return ""; } static inline const char * mcp251xfd_get_model_str(const struct mcp251xfd_priv *priv) { return __mcp251xfd_get_model_str(priv->devtype_data.model); } static const char *mcp251xfd_get_mode_str(const u8 mode) { switch (mode) { case MCP251XFD_REG_CON_MODE_MIXED: return "Mixed (CAN FD/CAN 2.0)"; case MCP251XFD_REG_CON_MODE_SLEEP: return "Sleep"; case MCP251XFD_REG_CON_MODE_INT_LOOPBACK: return "Internal Loopback"; case MCP251XFD_REG_CON_MODE_LISTENONLY: return "Listen Only"; case MCP251XFD_REG_CON_MODE_CONFIG: return "Configuration"; case MCP251XFD_REG_CON_MODE_EXT_LOOPBACK: return "External Loopback"; case MCP251XFD_REG_CON_MODE_CAN2_0: return "CAN 2.0"; case MCP251XFD_REG_CON_MODE_RESTRICTED: return "Restricted Operation"; } return ""; } static const char * mcp251xfd_get_osc_str(const u32 osc, const u32 osc_reference) { switch (~osc & osc_reference & (MCP251XFD_REG_OSC_OSCRDY | MCP251XFD_REG_OSC_PLLRDY)) { case MCP251XFD_REG_OSC_PLLRDY: return "PLL"; case MCP251XFD_REG_OSC_OSCRDY: return "Oscillator"; case MCP251XFD_REG_OSC_PLLRDY | MCP251XFD_REG_OSC_OSCRDY: return "Oscillator/PLL"; } return ""; } static inline int mcp251xfd_vdd_enable(const struct mcp251xfd_priv *priv) { if (!priv->reg_vdd) return 0; return regulator_enable(priv->reg_vdd); } static inline int mcp251xfd_vdd_disable(const struct mcp251xfd_priv *priv) { if (!priv->reg_vdd) return 0; return regulator_disable(priv->reg_vdd); } static inline int mcp251xfd_transceiver_enable(const struct mcp251xfd_priv *priv) { if (!priv->reg_xceiver) return 0; return regulator_enable(priv->reg_xceiver); } static inline int mcp251xfd_transceiver_disable(const struct mcp251xfd_priv *priv) { if (!priv->reg_xceiver) return 0; return regulator_disable(priv->reg_xceiver); } static int mcp251xfd_clks_and_vdd_enable(const struct mcp251xfd_priv *priv) { int err; err = clk_prepare_enable(priv->clk); if (err) return err; err = mcp251xfd_vdd_enable(priv); if (err) clk_disable_unprepare(priv->clk); /* Wait for oscillator stabilisation time after power up */ usleep_range(MCP251XFD_OSC_STAB_SLEEP_US, 2 * MCP251XFD_OSC_STAB_SLEEP_US); return err; } static int mcp251xfd_clks_and_vdd_disable(const struct mcp251xfd_priv *priv) { int err; err = mcp251xfd_vdd_disable(priv); if (err) return err; clk_disable_unprepare(priv->clk); return 0; } static inline bool mcp251xfd_reg_invalid(u32 reg) { return reg == 0x0 || reg == 0xffffffff; } static inline int mcp251xfd_chip_get_mode(const struct mcp251xfd_priv *priv, u8 *mode) { u32 val; int err; err = regmap_read(priv->map_reg, MCP251XFD_REG_CON, &val); if (err) return err; *mode = FIELD_GET(MCP251XFD_REG_CON_OPMOD_MASK, val); return 0; } static int __mcp251xfd_chip_set_mode(const struct mcp251xfd_priv *priv, const u8 mode_req, bool nowait) { u32 con = 0, con_reqop, osc = 0; u8 mode; int err; con_reqop = FIELD_PREP(MCP251XFD_REG_CON_REQOP_MASK, mode_req); err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_CON, MCP251XFD_REG_CON_REQOP_MASK, con_reqop); if (err == -EBADMSG) { netdev_err(priv->ndev, "Failed to set Requested Operation Mode.\n"); return -ENODEV; } else if (err) { return err; } if (mode_req == MCP251XFD_REG_CON_MODE_SLEEP || nowait) return 0; err = regmap_read_poll_timeout(priv->map_reg, MCP251XFD_REG_CON, con, !mcp251xfd_reg_invalid(con) && FIELD_GET(MCP251XFD_REG_CON_OPMOD_MASK, con) == mode_req, MCP251XFD_POLL_SLEEP_US, MCP251XFD_POLL_TIMEOUT_US); if (err != -ETIMEDOUT && err != -EBADMSG) return err; /* Ignore return value. * Print below error messages, even if this fails. */ regmap_read(priv->map_reg, MCP251XFD_REG_OSC, &osc); if (mcp251xfd_reg_invalid(con)) { netdev_err(priv->ndev, "Failed to read CAN Control Register (con=0x%08x, osc=0x%08x).\n", con, osc); return -ENODEV; } mode = FIELD_GET(MCP251XFD_REG_CON_OPMOD_MASK, con); netdev_err(priv->ndev, "Controller failed to enter mode %s Mode (%u) and stays in %s Mode (%u) (con=0x%08x, osc=0x%08x).\n", mcp251xfd_get_mode_str(mode_req), mode_req, mcp251xfd_get_mode_str(mode), mode, con, osc); return -ETIMEDOUT; } static inline int mcp251xfd_chip_set_mode(const struct mcp251xfd_priv *priv, const u8 mode_req) { return __mcp251xfd_chip_set_mode(priv, mode_req, false); } static inline int __maybe_unused mcp251xfd_chip_set_mode_nowait(const struct mcp251xfd_priv *priv, const u8 mode_req) { return __mcp251xfd_chip_set_mode(priv, mode_req, true); } static int mcp251xfd_chip_wait_for_osc_ready(const struct mcp251xfd_priv *priv, u32 osc_reference, u32 osc_mask) { u32 osc; int err; err = regmap_read_poll_timeout(priv->map_reg, MCP251XFD_REG_OSC, osc, !mcp251xfd_reg_invalid(osc) && (osc & osc_mask) == osc_reference, MCP251XFD_OSC_STAB_SLEEP_US, MCP251XFD_OSC_STAB_TIMEOUT_US); if (err != -ETIMEDOUT) return err; if (mcp251xfd_reg_invalid(osc)) { netdev_err(priv->ndev, "Failed to read Oscillator Configuration Register (osc=0x%08x).\n", osc); return -ENODEV; } netdev_err(priv->ndev, "Timeout waiting for %s ready (osc=0x%08x, osc_reference=0x%08x, osc_mask=0x%08x).\n", mcp251xfd_get_osc_str(osc, osc_reference), osc, osc_reference, osc_mask); return -ETIMEDOUT; } static int mcp251xfd_chip_wake(const struct mcp251xfd_priv *priv) { u32 osc, osc_reference, osc_mask; int err; /* For normal sleep on MCP2517FD and MCP2518FD, clearing * "Oscillator Disable" will wake the chip. For low power mode * on MCP2518FD, asserting the chip select will wake the * chip. Writing to the Oscillator register will wake it in * both cases. */ osc = FIELD_PREP(MCP251XFD_REG_OSC_CLKODIV_MASK, MCP251XFD_REG_OSC_CLKODIV_10); /* We cannot check for the PLL ready bit (either set or * unset), as the PLL might be enabled. This can happen if the * system reboots, while the mcp251xfd stays powered. */ osc_reference = MCP251XFD_REG_OSC_OSCRDY; osc_mask = MCP251XFD_REG_OSC_OSCRDY; /* If the controller is in Sleep Mode the following write only * removes the "Oscillator Disable" bit and powers it up. All * other bits are unaffected. */ err = regmap_write(priv->map_reg, MCP251XFD_REG_OSC, osc); if (err) return err; /* Sometimes the PLL is stuck enabled, the controller never * sets the OSC Ready bit, and we get an -ETIMEDOUT. Our * caller takes care of retry. */ return mcp251xfd_chip_wait_for_osc_ready(priv, osc_reference, osc_mask); } static inline int mcp251xfd_chip_sleep(const struct mcp251xfd_priv *priv) { if (priv->pll_enable) { u32 osc; int err; /* Turn off PLL */ osc = FIELD_PREP(MCP251XFD_REG_OSC_CLKODIV_MASK, MCP251XFD_REG_OSC_CLKODIV_10); err = regmap_write(priv->map_reg, MCP251XFD_REG_OSC, osc); if (err) netdev_err(priv->ndev, "Failed to disable PLL.\n"); priv->spi->max_speed_hz = priv->spi_max_speed_hz_slow; } return mcp251xfd_chip_set_mode(priv, MCP251XFD_REG_CON_MODE_SLEEP); } static int mcp251xfd_chip_softreset_do(const struct mcp251xfd_priv *priv) { const __be16 cmd = mcp251xfd_cmd_reset(); int err; /* The Set Mode and SPI Reset command only works if the * controller is not in Sleep Mode. */ err = mcp251xfd_chip_wake(priv); if (err) return err; err = mcp251xfd_chip_set_mode(priv, MCP251XFD_REG_CON_MODE_CONFIG); if (err) return err; /* spi_write_then_read() works with non DMA-safe buffers */ return spi_write_then_read(priv->spi, &cmd, sizeof(cmd), NULL, 0); } static int mcp251xfd_chip_softreset_check(const struct mcp251xfd_priv *priv) { u32 osc_reference, osc_mask; u8 mode; int err; /* Check for reset defaults of OSC reg. * This will take care of stabilization period. */ osc_reference = MCP251XFD_REG_OSC_OSCRDY | FIELD_PREP(MCP251XFD_REG_OSC_CLKODIV_MASK, MCP251XFD_REG_OSC_CLKODIV_10); osc_mask = osc_reference | MCP251XFD_REG_OSC_PLLRDY; err = mcp251xfd_chip_wait_for_osc_ready(priv, osc_reference, osc_mask); if (err) return err; err = mcp251xfd_chip_get_mode(priv, &mode); if (err) return err; if (mode != MCP251XFD_REG_CON_MODE_CONFIG) { netdev_info(priv->ndev, "Controller not in Config Mode after reset, but in %s Mode (%u).\n", mcp251xfd_get_mode_str(mode), mode); return -ETIMEDOUT; } return 0; } static int mcp251xfd_chip_softreset(const struct mcp251xfd_priv *priv) { int err, i; for (i = 0; i < MCP251XFD_SOFTRESET_RETRIES_MAX; i++) { if (i) netdev_info(priv->ndev, "Retrying to reset controller.\n"); err = mcp251xfd_chip_softreset_do(priv); if (err == -ETIMEDOUT) continue; if (err) return err; err = mcp251xfd_chip_softreset_check(priv); if (err == -ETIMEDOUT) continue; if (err) return err; return 0; } return err; } static int mcp251xfd_chip_clock_init(const struct mcp251xfd_priv *priv) { u32 osc, osc_reference, osc_mask; int err; /* Activate Low Power Mode on Oscillator Disable. This only * works on the MCP2518FD. The MCP2517FD will go into normal * Sleep Mode instead. */ osc = MCP251XFD_REG_OSC_LPMEN | FIELD_PREP(MCP251XFD_REG_OSC_CLKODIV_MASK, MCP251XFD_REG_OSC_CLKODIV_10); osc_reference = MCP251XFD_REG_OSC_OSCRDY; osc_mask = MCP251XFD_REG_OSC_OSCRDY | MCP251XFD_REG_OSC_PLLRDY; if (priv->pll_enable) { osc |= MCP251XFD_REG_OSC_PLLEN; osc_reference |= MCP251XFD_REG_OSC_PLLRDY; } err = regmap_write(priv->map_reg, MCP251XFD_REG_OSC, osc); if (err) return err; err = mcp251xfd_chip_wait_for_osc_ready(priv, osc_reference, osc_mask); if (err) return err; priv->spi->max_speed_hz = priv->spi_max_speed_hz_fast; return 0; } static int mcp251xfd_chip_timestamp_init(const struct mcp251xfd_priv *priv) { /* Set Time Base Counter Prescaler to 1. * * This means an overflow of the 32 bit Time Base Counter * register at 40 MHz every 107 seconds. */ return regmap_write(priv->map_reg, MCP251XFD_REG_TSCON, MCP251XFD_REG_TSCON_TBCEN); } static int mcp251xfd_set_bittiming(const struct mcp251xfd_priv *priv) { const struct can_bittiming *bt = &priv->can.bittiming; const struct can_bittiming *dbt = &priv->can.data_bittiming; u32 val = 0; s8 tdco; int err; /* CAN Control Register * * - no transmit bandwidth sharing * - config mode * - disable transmit queue * - store in transmit FIFO event * - transition to restricted operation mode on system error * - ESI is transmitted recessive when ESI of message is high or * CAN controller error passive * - restricted retransmission attempts, * use TQXCON_TXAT and FIFOCON_TXAT * - wake-up filter bits T11FILTER * - use CAN bus line filter for wakeup * - protocol exception is treated as a form error * - Do not compare data bytes */ val = FIELD_PREP(MCP251XFD_REG_CON_REQOP_MASK, MCP251XFD_REG_CON_MODE_CONFIG) | MCP251XFD_REG_CON_STEF | MCP251XFD_REG_CON_ESIGM | MCP251XFD_REG_CON_RTXAT | FIELD_PREP(MCP251XFD_REG_CON_WFT_MASK, MCP251XFD_REG_CON_WFT_T11FILTER) | MCP251XFD_REG_CON_WAKFIL | MCP251XFD_REG_CON_PXEDIS; if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)) val |= MCP251XFD_REG_CON_ISOCRCEN; err = regmap_write(priv->map_reg, MCP251XFD_REG_CON, val); if (err) return err; /* Nominal Bit Time */ val = FIELD_PREP(MCP251XFD_REG_NBTCFG_BRP_MASK, bt->brp - 1) | FIELD_PREP(MCP251XFD_REG_NBTCFG_TSEG1_MASK, bt->prop_seg + bt->phase_seg1 - 1) | FIELD_PREP(MCP251XFD_REG_NBTCFG_TSEG2_MASK, bt->phase_seg2 - 1) | FIELD_PREP(MCP251XFD_REG_NBTCFG_SJW_MASK, bt->sjw - 1); err = regmap_write(priv->map_reg, MCP251XFD_REG_NBTCFG, val); if (err) return err; if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD)) return 0; /* Data Bit Time */ val = FIELD_PREP(MCP251XFD_REG_DBTCFG_BRP_MASK, dbt->brp - 1) | FIELD_PREP(MCP251XFD_REG_DBTCFG_TSEG1_MASK, dbt->prop_seg + dbt->phase_seg1 - 1) | FIELD_PREP(MCP251XFD_REG_DBTCFG_TSEG2_MASK, dbt->phase_seg2 - 1) | FIELD_PREP(MCP251XFD_REG_DBTCFG_SJW_MASK, dbt->sjw - 1); err = regmap_write(priv->map_reg, MCP251XFD_REG_DBTCFG, val); if (err) return err; /* Transmitter Delay Compensation */ tdco = clamp_t(int, dbt->brp * (dbt->prop_seg + dbt->phase_seg1), -64, 63); val = FIELD_PREP(MCP251XFD_REG_TDC_TDCMOD_MASK, MCP251XFD_REG_TDC_TDCMOD_AUTO) | FIELD_PREP(MCP251XFD_REG_TDC_TDCO_MASK, tdco); return regmap_write(priv->map_reg, MCP251XFD_REG_TDC, val); } static int mcp251xfd_chip_rx_int_enable(const struct mcp251xfd_priv *priv) { u32 val; if (!priv->rx_int) return 0; /* Configure GPIOs: * - PIN0: GPIO Input * - PIN1: GPIO Input/RX Interrupt * * PIN1 must be Input, otherwise there is a glitch on the * rx-INT line. It happens between setting the PIN as output * (in the first byte of the SPI transfer) and configuring the * PIN as interrupt (in the last byte of the SPI transfer). */ val = MCP251XFD_REG_IOCON_PM0 | MCP251XFD_REG_IOCON_TRIS1 | MCP251XFD_REG_IOCON_TRIS0; return regmap_write(priv->map_reg, MCP251XFD_REG_IOCON, val); } static int mcp251xfd_chip_rx_int_disable(const struct mcp251xfd_priv *priv) { u32 val; if (!priv->rx_int) return 0; /* Configure GPIOs: * - PIN0: GPIO Input * - PIN1: GPIO Input */ val = MCP251XFD_REG_IOCON_PM1 | MCP251XFD_REG_IOCON_PM0 | MCP251XFD_REG_IOCON_TRIS1 | MCP251XFD_REG_IOCON_TRIS0; return regmap_write(priv->map_reg, MCP251XFD_REG_IOCON, val); } static int mcp251xfd_chip_ecc_init(struct mcp251xfd_priv *priv) { struct mcp251xfd_ecc *ecc = &priv->ecc; void *ram; u32 val = 0; int err; ecc->ecc_stat = 0; if (priv->devtype_data.quirks & MCP251XFD_QUIRK_ECC) val = MCP251XFD_REG_ECCCON_ECCEN; err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_ECCCON, MCP251XFD_REG_ECCCON_ECCEN, val); if (err) return err; ram = kzalloc(MCP251XFD_RAM_SIZE, GFP_KERNEL); if (!ram) return -ENOMEM; err = regmap_raw_write(priv->map_reg, MCP251XFD_RAM_START, ram, MCP251XFD_RAM_SIZE); kfree(ram); return err; } static u8 mcp251xfd_get_normal_mode(const struct mcp251xfd_priv *priv) { u8 mode; if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) mode = MCP251XFD_REG_CON_MODE_INT_LOOPBACK; else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) mode = MCP251XFD_REG_CON_MODE_LISTENONLY; else if (priv->can.ctrlmode & CAN_CTRLMODE_FD) mode = MCP251XFD_REG_CON_MODE_MIXED; else mode = MCP251XFD_REG_CON_MODE_CAN2_0; return mode; } static int __mcp251xfd_chip_set_normal_mode(const struct mcp251xfd_priv *priv, bool nowait) { u8 mode; mode = mcp251xfd_get_normal_mode(priv); return __mcp251xfd_chip_set_mode(priv, mode, nowait); } static inline int mcp251xfd_chip_set_normal_mode(const struct mcp251xfd_priv *priv) { return __mcp251xfd_chip_set_normal_mode(priv, false); } static inline int mcp251xfd_chip_set_normal_mode_nowait(const struct mcp251xfd_priv *priv) { return __mcp251xfd_chip_set_normal_mode(priv, true); } static int mcp251xfd_chip_interrupts_enable(const struct mcp251xfd_priv *priv) { u32 val; int err; val = MCP251XFD_REG_CRC_FERRIE | MCP251XFD_REG_CRC_CRCERRIE; err = regmap_write(priv->map_reg, MCP251XFD_REG_CRC, val); if (err) return err; val = MCP251XFD_REG_ECCCON_DEDIE | MCP251XFD_REG_ECCCON_SECIE; err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_ECCCON, val, val); if (err) return err; val = MCP251XFD_REG_INT_CERRIE | MCP251XFD_REG_INT_SERRIE | MCP251XFD_REG_INT_RXOVIE | MCP251XFD_REG_INT_TXATIE | MCP251XFD_REG_INT_SPICRCIE | MCP251XFD_REG_INT_ECCIE | MCP251XFD_REG_INT_TEFIE | MCP251XFD_REG_INT_MODIE | MCP251XFD_REG_INT_RXIE; if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) val |= MCP251XFD_REG_INT_IVMIE; return regmap_write(priv->map_reg, MCP251XFD_REG_INT, val); } static int mcp251xfd_chip_interrupts_disable(const struct mcp251xfd_priv *priv) { int err; u32 mask; err = regmap_write(priv->map_reg, MCP251XFD_REG_INT, 0); if (err) return err; mask = MCP251XFD_REG_ECCCON_DEDIE | MCP251XFD_REG_ECCCON_SECIE; err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_ECCCON, mask, 0x0); if (err) return err; return regmap_write(priv->map_reg, MCP251XFD_REG_CRC, 0); } static void mcp251xfd_chip_stop(struct mcp251xfd_priv *priv, const enum can_state state) { priv->can.state = state; mcp251xfd_chip_interrupts_disable(priv); mcp251xfd_chip_rx_int_disable(priv); mcp251xfd_chip_sleep(priv); } static int mcp251xfd_chip_start(struct mcp251xfd_priv *priv) { int err; err = mcp251xfd_chip_softreset(priv); if (err) goto out_chip_stop; err = mcp251xfd_chip_clock_init(priv); if (err) goto out_chip_stop; err = mcp251xfd_chip_timestamp_init(priv); if (err) goto out_chip_stop; err = mcp251xfd_set_bittiming(priv); if (err) goto out_chip_stop; err = mcp251xfd_chip_rx_int_enable(priv); if (err) goto out_chip_stop; err = mcp251xfd_chip_ecc_init(priv); if (err) goto out_chip_stop; err = mcp251xfd_ring_init(priv); if (err) goto out_chip_stop; err = mcp251xfd_chip_fifo_init(priv); if (err) goto out_chip_stop; priv->can.state = CAN_STATE_ERROR_ACTIVE; err = mcp251xfd_chip_set_normal_mode(priv); if (err) goto out_chip_stop; return 0; out_chip_stop: mcp251xfd_dump(priv); mcp251xfd_chip_stop(priv, CAN_STATE_STOPPED); return err; } static int mcp251xfd_set_mode(struct net_device *ndev, enum can_mode mode) { struct mcp251xfd_priv *priv = netdev_priv(ndev); int err; switch (mode) { case CAN_MODE_START: err = mcp251xfd_chip_start(priv); if (err) return err; err = mcp251xfd_chip_interrupts_enable(priv); if (err) { mcp251xfd_chip_stop(priv, CAN_STATE_STOPPED); return err; } netif_wake_queue(ndev); break; default: return -EOPNOTSUPP; } return 0; } static int __mcp251xfd_get_berr_counter(const struct net_device *ndev, struct can_berr_counter *bec) { const struct mcp251xfd_priv *priv = netdev_priv(ndev); u32 trec; int err; err = regmap_read(priv->map_reg, MCP251XFD_REG_TREC, &trec); if (err) return err; if (trec & MCP251XFD_REG_TREC_TXBO) bec->txerr = 256; else bec->txerr = FIELD_GET(MCP251XFD_REG_TREC_TEC_MASK, trec); bec->rxerr = FIELD_GET(MCP251XFD_REG_TREC_REC_MASK, trec); return 0; } static int mcp251xfd_get_berr_counter(const struct net_device *ndev, struct can_berr_counter *bec) { const struct mcp251xfd_priv *priv = netdev_priv(ndev); /* Avoid waking up the controller if the interface is down */ if (!(ndev->flags & IFF_UP)) return 0; /* The controller is powered down during Bus Off, use saved * bec values. */ if (priv->can.state == CAN_STATE_BUS_OFF) { *bec = priv->bec; return 0; } return __mcp251xfd_get_berr_counter(ndev, bec); } static struct sk_buff * mcp251xfd_alloc_can_err_skb(struct mcp251xfd_priv *priv, struct can_frame **cf, u32 *timestamp) { struct sk_buff *skb; int err; err = mcp251xfd_get_timestamp(priv, timestamp); if (err) return NULL; skb = alloc_can_err_skb(priv->ndev, cf); if (skb) mcp251xfd_skb_set_timestamp(priv, skb, *timestamp); return skb; } static int mcp251xfd_handle_rxovif(struct mcp251xfd_priv *priv) { struct net_device_stats *stats = &priv->ndev->stats; struct mcp251xfd_rx_ring *ring; struct sk_buff *skb; struct can_frame *cf; u32 timestamp, rxovif; int err, i; stats->rx_over_errors++; stats->rx_errors++; err = regmap_read(priv->map_reg, MCP251XFD_REG_RXOVIF, &rxovif); if (err) return err; mcp251xfd_for_each_rx_ring(priv, ring, i) { if (!(rxovif & BIT(ring->fifo_nr))) continue; /* If SERRIF is active, there was a RX MAB overflow. */ if (priv->regs_status.intf & MCP251XFD_REG_INT_SERRIF) { if (net_ratelimit()) netdev_dbg(priv->ndev, "RX-%d: MAB overflow detected.\n", ring->nr); } else { if (net_ratelimit()) netdev_dbg(priv->ndev, "RX-%d: FIFO overflow.\n", ring->nr); } err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_FIFOSTA(ring->fifo_nr), MCP251XFD_REG_FIFOSTA_RXOVIF, 0x0); if (err) return err; } skb = mcp251xfd_alloc_can_err_skb(priv, &cf, ×tamp); if (!skb) return 0; cf->can_id |= CAN_ERR_CRTL; cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp); if (err) stats->rx_fifo_errors++; return 0; } static int mcp251xfd_handle_txatif(struct mcp251xfd_priv *priv) { netdev_info(priv->ndev, "%s\n", __func__); return 0; } static int mcp251xfd_handle_ivmif(struct mcp251xfd_priv *priv) { struct net_device_stats *stats = &priv->ndev->stats; u32 bdiag1, timestamp; struct sk_buff *skb; struct can_frame *cf = NULL; int err; err = mcp251xfd_get_timestamp(priv, ×tamp); if (err) return err; err = regmap_read(priv->map_reg, MCP251XFD_REG_BDIAG1, &bdiag1); if (err) return err; /* Write 0s to clear error bits, don't write 1s to non active * bits, as they will be set. */ err = regmap_write(priv->map_reg, MCP251XFD_REG_BDIAG1, 0x0); if (err) return err; priv->can.can_stats.bus_error++; skb = alloc_can_err_skb(priv->ndev, &cf); if (cf) cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; /* Controller misconfiguration */ if (WARN_ON(bdiag1 & MCP251XFD_REG_BDIAG1_DLCMM)) netdev_err(priv->ndev, "recv'd DLC is larger than PLSIZE of FIFO element."); /* RX errors */ if (bdiag1 & (MCP251XFD_REG_BDIAG1_DCRCERR | MCP251XFD_REG_BDIAG1_NCRCERR)) { netdev_dbg(priv->ndev, "CRC error\n"); stats->rx_errors++; if (cf) cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ; } if (bdiag1 & (MCP251XFD_REG_BDIAG1_DSTUFERR | MCP251XFD_REG_BDIAG1_NSTUFERR)) { netdev_dbg(priv->ndev, "Stuff error\n"); stats->rx_errors++; if (cf) cf->data[2] |= CAN_ERR_PROT_STUFF; } if (bdiag1 & (MCP251XFD_REG_BDIAG1_DFORMERR | MCP251XFD_REG_BDIAG1_NFORMERR)) { netdev_dbg(priv->ndev, "Format error\n"); stats->rx_errors++; if (cf) cf->data[2] |= CAN_ERR_PROT_FORM; } /* TX errors */ if (bdiag1 & MCP251XFD_REG_BDIAG1_NACKERR) { netdev_dbg(priv->ndev, "NACK error\n"); stats->tx_errors++; if (cf) { cf->can_id |= CAN_ERR_ACK; cf->data[2] |= CAN_ERR_PROT_TX; } } if (bdiag1 & (MCP251XFD_REG_BDIAG1_DBIT1ERR | MCP251XFD_REG_BDIAG1_NBIT1ERR)) { netdev_dbg(priv->ndev, "Bit1 error\n"); stats->tx_errors++; if (cf) cf->data[2] |= CAN_ERR_PROT_TX | CAN_ERR_PROT_BIT1; } if (bdiag1 & (MCP251XFD_REG_BDIAG1_DBIT0ERR | MCP251XFD_REG_BDIAG1_NBIT0ERR)) { netdev_dbg(priv->ndev, "Bit0 error\n"); stats->tx_errors++; if (cf) cf->data[2] |= CAN_ERR_PROT_TX | CAN_ERR_PROT_BIT0; } if (!cf) return 0; mcp251xfd_skb_set_timestamp(priv, skb, timestamp); err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp); if (err) stats->rx_fifo_errors++; return 0; } static int mcp251xfd_handle_cerrif(struct mcp251xfd_priv *priv) { struct net_device_stats *stats = &priv->ndev->stats; struct sk_buff *skb; struct can_frame *cf = NULL; enum can_state new_state, rx_state, tx_state; u32 trec, timestamp; int err; err = regmap_read(priv->map_reg, MCP251XFD_REG_TREC, &trec); if (err) return err; if (trec & MCP251XFD_REG_TREC_TXBO) tx_state = CAN_STATE_BUS_OFF; else if (trec & MCP251XFD_REG_TREC_TXBP) tx_state = CAN_STATE_ERROR_PASSIVE; else if (trec & MCP251XFD_REG_TREC_TXWARN) tx_state = CAN_STATE_ERROR_WARNING; else tx_state = CAN_STATE_ERROR_ACTIVE; if (trec & MCP251XFD_REG_TREC_RXBP) rx_state = CAN_STATE_ERROR_PASSIVE; else if (trec & MCP251XFD_REG_TREC_RXWARN) rx_state = CAN_STATE_ERROR_WARNING; else rx_state = CAN_STATE_ERROR_ACTIVE; new_state = max(tx_state, rx_state); if (new_state == priv->can.state) return 0; /* The skb allocation might fail, but can_change_state() * handles cf == NULL. */ skb = mcp251xfd_alloc_can_err_skb(priv, &cf, ×tamp); can_change_state(priv->ndev, cf, tx_state, rx_state); if (new_state == CAN_STATE_BUS_OFF) { /* As we're going to switch off the chip now, let's * save the error counters and return them to * userspace, if do_get_berr_counter() is called while * the chip is in Bus Off. */ err = __mcp251xfd_get_berr_counter(priv->ndev, &priv->bec); if (err) return err; mcp251xfd_chip_stop(priv, CAN_STATE_BUS_OFF); can_bus_off(priv->ndev); } if (!skb) return 0; if (new_state != CAN_STATE_BUS_OFF) { struct can_berr_counter bec; err = mcp251xfd_get_berr_counter(priv->ndev, &bec); if (err) return err; cf->data[6] = bec.txerr; cf->data[7] = bec.rxerr; } err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp); if (err) stats->rx_fifo_errors++; return 0; } static int mcp251xfd_handle_modif(const struct mcp251xfd_priv *priv, bool *set_normal_mode) { const u8 mode_reference = mcp251xfd_get_normal_mode(priv); u8 mode; int err; err = mcp251xfd_chip_get_mode(priv, &mode); if (err) return err; if (mode == mode_reference) { netdev_dbg(priv->ndev, "Controller changed into %s Mode (%u).\n", mcp251xfd_get_mode_str(mode), mode); return 0; } /* According to MCP2517FD errata DS80000792B 1., during a TX * MAB underflow, the controller will transition to Restricted * Operation Mode or Listen Only Mode (depending on SERR2LOM). * * However this is not always the case. If SERR2LOM is * configured for Restricted Operation Mode (SERR2LOM not set) * the MCP2517FD will sometimes transition to Listen Only Mode * first. When polling this bit we see that it will transition * to Restricted Operation Mode shortly after. */ if ((priv->devtype_data.quirks & MCP251XFD_QUIRK_MAB_NO_WARN) && (mode == MCP251XFD_REG_CON_MODE_RESTRICTED || mode == MCP251XFD_REG_CON_MODE_LISTENONLY)) netdev_dbg(priv->ndev, "Controller changed into %s Mode (%u).\n", mcp251xfd_get_mode_str(mode), mode); else netdev_err(priv->ndev, "Controller changed into %s Mode (%u).\n", mcp251xfd_get_mode_str(mode), mode); /* After the application requests Normal mode, the controller * will automatically attempt to retransmit the message that * caused the TX MAB underflow. * * However, if there is an ECC error in the TX-RAM, we first * have to reload the tx-object before requesting Normal * mode. This is done later in mcp251xfd_handle_eccif(). */ if (priv->regs_status.intf & MCP251XFD_REG_INT_ECCIF) { *set_normal_mode = true; return 0; } return mcp251xfd_chip_set_normal_mode_nowait(priv); } static int mcp251xfd_handle_serrif(struct mcp251xfd_priv *priv) { struct mcp251xfd_ecc *ecc = &priv->ecc; struct net_device_stats *stats = &priv->ndev->stats; bool handled = false; /* TX MAB underflow * * According to MCP2517FD Errata DS80000792B 1. a TX MAB * underflow is indicated by SERRIF and MODIF. * * In addition to the effects mentioned in the Errata, there * are Bus Errors due to the aborted CAN frame, so a IVMIF * will be seen as well. * * Sometimes there is an ECC error in the TX-RAM, which leads * to a TX MAB underflow. * * However, probably due to a race condition, there is no * associated MODIF pending. * * Further, there are situations, where the SERRIF is caused * by an ECC error in the TX-RAM, but not even the ECCIF is * set. This only seems to happen _after_ the first occurrence * of a ECCIF (which is tracked in ecc->cnt). * * Treat all as a known system errors.. */ if ((priv->regs_status.intf & MCP251XFD_REG_INT_MODIF && priv->regs_status.intf & MCP251XFD_REG_INT_IVMIF) || priv->regs_status.intf & MCP251XFD_REG_INT_ECCIF || ecc->cnt) { const char *msg; if (priv->regs_status.intf & MCP251XFD_REG_INT_ECCIF || ecc->cnt) msg = "TX MAB underflow due to ECC error detected."; else msg = "TX MAB underflow detected."; if (priv->devtype_data.quirks & MCP251XFD_QUIRK_MAB_NO_WARN) netdev_dbg(priv->ndev, "%s\n", msg); else netdev_info(priv->ndev, "%s\n", msg); stats->tx_aborted_errors++; stats->tx_errors++; handled = true; } /* RX MAB overflow * * According to MCP2517FD Errata DS80000792B 1. a RX MAB * overflow is indicated by SERRIF. * * In addition to the effects mentioned in the Errata, (most * of the times) a RXOVIF is raised, if the FIFO that is being * received into has the RXOVIE activated (and we have enabled * RXOVIE on all FIFOs). * * Sometimes there is no RXOVIF just a RXIF is pending. * * Treat all as a known system errors.. */ if (priv->regs_status.intf & MCP251XFD_REG_INT_RXOVIF || priv->regs_status.intf & MCP251XFD_REG_INT_RXIF) { stats->rx_dropped++; handled = true; } if (!handled) netdev_err(priv->ndev, "Unhandled System Error Interrupt (intf=0x%08x)!\n", priv->regs_status.intf); return 0; } static int mcp251xfd_handle_eccif_recover(struct mcp251xfd_priv *priv, u8 nr) { struct mcp251xfd_tx_ring *tx_ring = priv->tx; struct mcp251xfd_ecc *ecc = &priv->ecc; struct mcp251xfd_tx_obj *tx_obj; u8 chip_tx_tail, tx_tail, offset; u16 addr; int err; addr = FIELD_GET(MCP251XFD_REG_ECCSTAT_ERRADDR_MASK, ecc->ecc_stat); err = mcp251xfd_tx_tail_get_from_chip(priv, &chip_tx_tail); if (err) return err; tx_tail = mcp251xfd_get_tx_tail(tx_ring); offset = (nr - chip_tx_tail) & (tx_ring->obj_num - 1); /* Bail out if one of the following is met: * - tx_tail information is inconsistent * - for mcp2517fd: offset not 0 * - for mcp2518fd: offset not 0 or 1 */ if (chip_tx_tail != tx_tail || !(offset == 0 || (offset == 1 && (mcp251xfd_is_2518FD(priv) || mcp251xfd_is_251863(priv))))) { netdev_err(priv->ndev, "ECC Error information inconsistent (addr=0x%04x, nr=%d, tx_tail=0x%08x(%d), chip_tx_tail=%d, offset=%d).\n", addr, nr, tx_ring->tail, tx_tail, chip_tx_tail, offset); return -EINVAL; } netdev_info(priv->ndev, "Recovering %s ECC Error at address 0x%04x (in TX-RAM, tx_obj=%d, tx_tail=0x%08x(%d), offset=%d).\n", ecc->ecc_stat & MCP251XFD_REG_ECCSTAT_SECIF ? "Single" : "Double", addr, nr, tx_ring->tail, tx_tail, offset); /* reload tx_obj into controller RAM ... */ tx_obj = &tx_ring->obj[nr]; err = spi_sync_transfer(priv->spi, tx_obj->xfer, 1); if (err) return err; /* ... and trigger retransmit */ return mcp251xfd_chip_set_normal_mode(priv); } static int mcp251xfd_handle_eccif(struct mcp251xfd_priv *priv, bool set_normal_mode) { struct mcp251xfd_ecc *ecc = &priv->ecc; const char *msg; bool in_tx_ram; u32 ecc_stat; u16 addr; u8 nr; int err; err = regmap_read(priv->map_reg, MCP251XFD_REG_ECCSTAT, &ecc_stat); if (err) return err; err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_ECCSTAT, MCP251XFD_REG_ECCSTAT_IF_MASK, ~ecc_stat); if (err) return err; /* Check if ECC error occurred in TX-RAM */ addr = FIELD_GET(MCP251XFD_REG_ECCSTAT_ERRADDR_MASK, ecc_stat); err = mcp251xfd_get_tx_nr_by_addr(priv->tx, &nr, addr); if (!err) in_tx_ram = true; else if (err == -ENOENT) in_tx_ram = false; else return err; /* Errata Reference: * mcp2517fd: DS80000789B, mcp2518fd: DS80000792C 2. * * ECC single error correction does not work in all cases: * * Fix/Work Around: * Enable single error correction and double error detection * interrupts by setting SECIE and DEDIE. Handle SECIF as a * detection interrupt and do not rely on the error * correction. Instead, handle both interrupts as a * notification that the RAM word at ERRADDR was corrupted. */ if (ecc_stat & MCP251XFD_REG_ECCSTAT_SECIF) msg = "Single ECC Error detected at address"; else if (ecc_stat & MCP251XFD_REG_ECCSTAT_DEDIF) msg = "Double ECC Error detected at address"; else return -EINVAL; if (!in_tx_ram) { ecc->ecc_stat = 0; netdev_notice(priv->ndev, "%s 0x%04x.\n", msg, addr); } else { /* Re-occurring error? */ if (ecc->ecc_stat == ecc_stat) { ecc->cnt++; } else { ecc->ecc_stat = ecc_stat; ecc->cnt = 1; } netdev_info(priv->ndev, "%s 0x%04x (in TX-RAM, tx_obj=%d), occurred %d time%s.\n", msg, addr, nr, ecc->cnt, ecc->cnt > 1 ? "s" : ""); if (ecc->cnt >= MCP251XFD_ECC_CNT_MAX) return mcp251xfd_handle_eccif_recover(priv, nr); } if (set_normal_mode) return mcp251xfd_chip_set_normal_mode_nowait(priv); return 0; } static int mcp251xfd_handle_spicrcif(struct mcp251xfd_priv *priv) { int err; u32 crc; err = regmap_read(priv->map_reg, MCP251XFD_REG_CRC, &crc); if (err) return err; err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_CRC, MCP251XFD_REG_CRC_IF_MASK, ~crc); if (err) return err; if (crc & MCP251XFD_REG_CRC_FERRIF) netdev_notice(priv->ndev, "CRC write command format error.\n"); else if (crc & MCP251XFD_REG_CRC_CRCERRIF) netdev_notice(priv->ndev, "CRC write error detected. CRC=0x%04lx.\n", FIELD_GET(MCP251XFD_REG_CRC_MASK, crc)); return 0; } static int mcp251xfd_read_regs_status(struct mcp251xfd_priv *priv) { const int val_bytes = regmap_get_val_bytes(priv->map_reg); size_t len; if (priv->rx_ring_num == 1) len = sizeof(priv->regs_status.intf); else len = sizeof(priv->regs_status); return regmap_bulk_read(priv->map_reg, MCP251XFD_REG_INT, &priv->regs_status, len / val_bytes); } #define mcp251xfd_handle(priv, irq, ...) \ ({ \ struct mcp251xfd_priv *_priv = (priv); \ int err; \ \ err = mcp251xfd_handle_##irq(_priv, ## __VA_ARGS__); \ if (err) \ netdev_err(_priv->ndev, \ "IRQ handler mcp251xfd_handle_%s() returned %d.\n", \ __stringify(irq), err); \ err; \ }) static irqreturn_t mcp251xfd_irq(int irq, void *dev_id) { struct mcp251xfd_priv *priv = dev_id; irqreturn_t handled = IRQ_NONE; int err; if (priv->rx_int) do { int rx_pending; rx_pending = gpiod_get_value_cansleep(priv->rx_int); if (!rx_pending) break; /* Assume 1st RX-FIFO pending, if other FIFOs * are pending the main IRQ handler will take * care. */ priv->regs_status.rxif = BIT(priv->rx[0]->fifo_nr); err = mcp251xfd_handle(priv, rxif); if (err) goto out_fail; handled = IRQ_HANDLED; /* We don't know which RX-FIFO is pending, but only * handle the 1st RX-FIFO. Leave loop here if we have * more than 1 RX-FIFO to avoid starvation. */ } while (priv->rx_ring_num == 1); do { u32 intf_pending, intf_pending_clearable; bool set_normal_mode = false; err = mcp251xfd_read_regs_status(priv); if (err) goto out_fail; intf_pending = FIELD_GET(MCP251XFD_REG_INT_IF_MASK, priv->regs_status.intf) & FIELD_GET(MCP251XFD_REG_INT_IE_MASK, priv->regs_status.intf); if (!(intf_pending)) { can_rx_offload_threaded_irq_finish(&priv->offload); return handled; } /* Some interrupts must be ACKed in the * MCP251XFD_REG_INT register. * - First ACK then handle, to avoid lost-IRQ race * condition on fast re-occurring interrupts. * - Write "0" to clear active IRQs, "1" to all other, * to avoid r/m/w race condition on the * MCP251XFD_REG_INT register. */ intf_pending_clearable = intf_pending & MCP251XFD_REG_INT_IF_CLEARABLE_MASK; if (intf_pending_clearable) { err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_INT, MCP251XFD_REG_INT_IF_MASK, ~intf_pending_clearable); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_MODIF) { err = mcp251xfd_handle(priv, modif, &set_normal_mode); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_RXIF) { err = mcp251xfd_handle(priv, rxif); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_TEFIF) { err = mcp251xfd_handle(priv, tefif); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_RXOVIF) { err = mcp251xfd_handle(priv, rxovif); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_TXATIF) { err = mcp251xfd_handle(priv, txatif); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_IVMIF) { err = mcp251xfd_handle(priv, ivmif); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_SERRIF) { err = mcp251xfd_handle(priv, serrif); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_ECCIF) { err = mcp251xfd_handle(priv, eccif, set_normal_mode); if (err) goto out_fail; } if (intf_pending & MCP251XFD_REG_INT_SPICRCIF) { err = mcp251xfd_handle(priv, spicrcif); if (err) goto out_fail; } /* On the MCP2527FD and MCP2518FD, we don't get a * CERRIF IRQ on the transition TX ERROR_WARNING -> TX * ERROR_ACTIVE. */ if (intf_pending & MCP251XFD_REG_INT_CERRIF || priv->can.state > CAN_STATE_ERROR_ACTIVE) { err = mcp251xfd_handle(priv, cerrif); if (err) goto out_fail; /* In Bus Off we completely shut down the * controller. Every subsequent register read * will read bogus data, and if * MCP251XFD_QUIRK_CRC_REG is enabled the CRC * check will fail, too. So leave IRQ handler * directly. */ if (priv->can.state == CAN_STATE_BUS_OFF) { can_rx_offload_threaded_irq_finish(&priv->offload); return IRQ_HANDLED; } } handled = IRQ_HANDLED; } while (1); out_fail: can_rx_offload_threaded_irq_finish(&priv->offload); netdev_err(priv->ndev, "IRQ handler returned %d (intf=0x%08x).\n", err, priv->regs_status.intf); mcp251xfd_dump(priv); mcp251xfd_chip_interrupts_disable(priv); mcp251xfd_timestamp_stop(priv); return handled; } static int mcp251xfd_open(struct net_device *ndev) { struct mcp251xfd_priv *priv = netdev_priv(ndev); const struct spi_device *spi = priv->spi; int err; err = open_candev(ndev); if (err) return err; err = pm_runtime_resume_and_get(ndev->dev.parent); if (err) goto out_close_candev; err = mcp251xfd_ring_alloc(priv); if (err) goto out_pm_runtime_put; err = mcp251xfd_transceiver_enable(priv); if (err) goto out_mcp251xfd_ring_free; err = mcp251xfd_chip_start(priv); if (err) goto out_transceiver_disable; mcp251xfd_timestamp_init(priv); clear_bit(MCP251XFD_FLAGS_DOWN, priv->flags); can_rx_offload_enable(&priv->offload); err = request_threaded_irq(spi->irq, NULL, mcp251xfd_irq, IRQF_SHARED | IRQF_ONESHOT, dev_name(&spi->dev), priv); if (err) goto out_can_rx_offload_disable; err = mcp251xfd_chip_interrupts_enable(priv); if (err) goto out_free_irq; netif_start_queue(ndev); return 0; out_free_irq: free_irq(spi->irq, priv); out_can_rx_offload_disable: can_rx_offload_disable(&priv->offload); set_bit(MCP251XFD_FLAGS_DOWN, priv->flags); mcp251xfd_timestamp_stop(priv); out_transceiver_disable: mcp251xfd_transceiver_disable(priv); out_mcp251xfd_ring_free: mcp251xfd_ring_free(priv); out_pm_runtime_put: mcp251xfd_chip_stop(priv, CAN_STATE_STOPPED); pm_runtime_put(ndev->dev.parent); out_close_candev: close_candev(ndev); return err; } static int mcp251xfd_stop(struct net_device *ndev) { struct mcp251xfd_priv *priv = netdev_priv(ndev); netif_stop_queue(ndev); set_bit(MCP251XFD_FLAGS_DOWN, priv->flags); hrtimer_cancel(&priv->rx_irq_timer); mcp251xfd_chip_interrupts_disable(priv); free_irq(ndev->irq, priv); can_rx_offload_disable(&priv->offload); mcp251xfd_timestamp_stop(priv); mcp251xfd_chip_stop(priv, CAN_STATE_STOPPED); mcp251xfd_transceiver_disable(priv); mcp251xfd_ring_free(priv); close_candev(ndev); pm_runtime_put(ndev->dev.parent); return 0; } static const struct net_device_ops mcp251xfd_netdev_ops = { .ndo_open = mcp251xfd_open, .ndo_stop = mcp251xfd_stop, .ndo_start_xmit = mcp251xfd_start_xmit, .ndo_change_mtu = can_change_mtu, }; static void mcp251xfd_register_quirks(struct mcp251xfd_priv *priv) { const struct spi_device *spi = priv->spi; const struct spi_controller *ctlr = spi->controller; if (ctlr->flags & SPI_CONTROLLER_HALF_DUPLEX) priv->devtype_data.quirks |= MCP251XFD_QUIRK_HALF_DUPLEX; } static int mcp251xfd_register_chip_detect(struct mcp251xfd_priv *priv) { const struct net_device *ndev = priv->ndev; const struct mcp251xfd_devtype_data *devtype_data; u32 osc; int err; /* The OSC_LPMEN is only supported on MCP2518FD, so use it to * autodetect the model. */ err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_OSC, MCP251XFD_REG_OSC_LPMEN, MCP251XFD_REG_OSC_LPMEN); if (err) return err; err = regmap_read(priv->map_reg, MCP251XFD_REG_OSC, &osc); if (err) return err; if (osc & MCP251XFD_REG_OSC_LPMEN) devtype_data = &mcp251xfd_devtype_data_mcp2518fd; else devtype_data = &mcp251xfd_devtype_data_mcp2517fd; if (!mcp251xfd_is_251XFD(priv) && priv->devtype_data.model != devtype_data->model) { netdev_info(ndev, "Detected %s, but firmware specifies a %s. Fixing up.\n", __mcp251xfd_get_model_str(devtype_data->model), mcp251xfd_get_model_str(priv)); } priv->devtype_data = *devtype_data; /* We need to preserve the Half Duplex Quirk. */ mcp251xfd_register_quirks(priv); /* Re-init regmap with quirks of detected model. */ return mcp251xfd_regmap_init(priv); } static int mcp251xfd_register_check_rx_int(struct mcp251xfd_priv *priv) { int err, rx_pending; if (!priv->rx_int) return 0; err = mcp251xfd_chip_rx_int_enable(priv); if (err) return err; /* Check if RX_INT is properly working. The RX_INT should not * be active after a softreset. */ rx_pending = gpiod_get_value_cansleep(priv->rx_int); err = mcp251xfd_chip_rx_int_disable(priv); if (err) return err; if (!rx_pending) return 0; netdev_info(priv->ndev, "RX_INT active after softreset, disabling RX_INT support.\n"); devm_gpiod_put(&priv->spi->dev, priv->rx_int); priv->rx_int = NULL; return 0; } static int mcp251xfd_register_get_dev_id(const struct mcp251xfd_priv *priv, u32 *dev_id, u32 *effective_speed_hz_slow, u32 *effective_speed_hz_fast) { struct mcp251xfd_map_buf_nocrc *buf_rx; struct mcp251xfd_map_buf_nocrc *buf_tx; struct spi_transfer xfer[2] = { }; int err; buf_rx = kzalloc(sizeof(*buf_rx), GFP_KERNEL); if (!buf_rx) return -ENOMEM; buf_tx = kzalloc(sizeof(*buf_tx), GFP_KERNEL); if (!buf_tx) { err = -ENOMEM; goto out_kfree_buf_rx; } xfer[0].tx_buf = buf_tx; xfer[0].len = sizeof(buf_tx->cmd); xfer[0].speed_hz = priv->spi_max_speed_hz_slow; xfer[1].rx_buf = buf_rx->data; xfer[1].len = sizeof(dev_id); xfer[1].speed_hz = priv->spi_max_speed_hz_fast; mcp251xfd_spi_cmd_read_nocrc(&buf_tx->cmd, MCP251XFD_REG_DEVID); err = spi_sync_transfer(priv->spi, xfer, ARRAY_SIZE(xfer)); if (err) goto out_kfree_buf_tx; *dev_id = be32_to_cpup((__be32 *)buf_rx->data); *effective_speed_hz_slow = xfer[0].effective_speed_hz; *effective_speed_hz_fast = xfer[1].effective_speed_hz; out_kfree_buf_tx: kfree(buf_tx); out_kfree_buf_rx: kfree(buf_rx); return err; } #define MCP251XFD_QUIRK_ACTIVE(quirk) \ (priv->devtype_data.quirks & MCP251XFD_QUIRK_##quirk ? '+' : '-') static int mcp251xfd_register_done(const struct mcp251xfd_priv *priv) { u32 dev_id, effective_speed_hz_slow, effective_speed_hz_fast; unsigned long clk_rate; int err; err = mcp251xfd_register_get_dev_id(priv, &dev_id, &effective_speed_hz_slow, &effective_speed_hz_fast); if (err) return err; clk_rate = clk_get_rate(priv->clk); netdev_info(priv->ndev, "%s rev%lu.%lu (%cRX_INT %cPLL %cMAB_NO_WARN %cCRC_REG %cCRC_RX %cCRC_TX %cECC %cHD o:%lu.%02luMHz c:%u.%02uMHz m:%u.%02uMHz rs:%u.%02uMHz es:%u.%02uMHz rf:%u.%02uMHz ef:%u.%02uMHz) successfully initialized.\n", mcp251xfd_get_model_str(priv), FIELD_GET(MCP251XFD_REG_DEVID_ID_MASK, dev_id), FIELD_GET(MCP251XFD_REG_DEVID_REV_MASK, dev_id), priv->rx_int ? '+' : '-', priv->pll_enable ? '+' : '-', MCP251XFD_QUIRK_ACTIVE(MAB_NO_WARN), MCP251XFD_QUIRK_ACTIVE(CRC_REG), MCP251XFD_QUIRK_ACTIVE(CRC_RX), MCP251XFD_QUIRK_ACTIVE(CRC_TX), MCP251XFD_QUIRK_ACTIVE(ECC), MCP251XFD_QUIRK_ACTIVE(HALF_DUPLEX), clk_rate / 1000000, clk_rate % 1000000 / 1000 / 10, priv->can.clock.freq / 1000000, priv->can.clock.freq % 1000000 / 1000 / 10, priv->spi_max_speed_hz_orig / 1000000, priv->spi_max_speed_hz_orig % 1000000 / 1000 / 10, priv->spi_max_speed_hz_slow / 1000000, priv->spi_max_speed_hz_slow % 1000000 / 1000 / 10, effective_speed_hz_slow / 1000000, effective_speed_hz_slow % 1000000 / 1000 / 10, priv->spi_max_speed_hz_fast / 1000000, priv->spi_max_speed_hz_fast % 1000000 / 1000 / 10, effective_speed_hz_fast / 1000000, effective_speed_hz_fast % 1000000 / 1000 / 10); return 0; } static int mcp251xfd_register(struct mcp251xfd_priv *priv) { struct net_device *ndev = priv->ndev; int err; err = mcp251xfd_clks_and_vdd_enable(priv); if (err) return err; pm_runtime_get_noresume(ndev->dev.parent); err = pm_runtime_set_active(ndev->dev.parent); if (err) goto out_runtime_put_noidle; pm_runtime_enable(ndev->dev.parent); mcp251xfd_register_quirks(priv); err = mcp251xfd_chip_softreset(priv); if (err == -ENODEV) goto out_runtime_disable; if (err) goto out_chip_sleep; err = mcp251xfd_chip_clock_init(priv); if (err == -ENODEV) goto out_runtime_disable; if (err) goto out_chip_sleep; err = mcp251xfd_register_chip_detect(priv); if (err) goto out_chip_sleep; err = mcp251xfd_register_check_rx_int(priv); if (err) goto out_chip_sleep; mcp251xfd_ethtool_init(priv); err = register_candev(ndev); if (err) goto out_chip_sleep; err = mcp251xfd_register_done(priv); if (err) goto out_unregister_candev; /* Put controller into sleep mode and let pm_runtime_put() * disable the clocks and vdd. If CONFIG_PM is not enabled, * the clocks and vdd will stay powered. */ err = mcp251xfd_chip_sleep(priv); if (err) goto out_unregister_candev; pm_runtime_put(ndev->dev.parent); return 0; out_unregister_candev: unregister_candev(ndev); out_chip_sleep: mcp251xfd_chip_sleep(priv); out_runtime_disable: pm_runtime_disable(ndev->dev.parent); out_runtime_put_noidle: pm_runtime_put_noidle(ndev->dev.parent); mcp251xfd_clks_and_vdd_disable(priv); return err; } static inline void mcp251xfd_unregister(struct mcp251xfd_priv *priv) { struct net_device *ndev = priv->ndev; unregister_candev(ndev); if (pm_runtime_enabled(ndev->dev.parent)) pm_runtime_disable(ndev->dev.parent); else mcp251xfd_clks_and_vdd_disable(priv); } static const struct of_device_id mcp251xfd_of_match[] = { { .compatible = "microchip,mcp2517fd", .data = &mcp251xfd_devtype_data_mcp2517fd, }, { .compatible = "microchip,mcp2518fd", .data = &mcp251xfd_devtype_data_mcp2518fd, }, { .compatible = "microchip,mcp251863", .data = &mcp251xfd_devtype_data_mcp251863, }, { .compatible = "microchip,mcp251xfd", .data = &mcp251xfd_devtype_data_mcp251xfd, }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, mcp251xfd_of_match); static const struct spi_device_id mcp251xfd_id_table[] = { { .name = "mcp2517fd", .driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp2517fd, }, { .name = "mcp2518fd", .driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp2518fd, }, { .name = "mcp251863", .driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp251863, }, { .name = "mcp251xfd", .driver_data = (kernel_ulong_t)&mcp251xfd_devtype_data_mcp251xfd, }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(spi, mcp251xfd_id_table); static int mcp251xfd_probe(struct spi_device *spi) { const void *match; struct net_device *ndev; struct mcp251xfd_priv *priv; struct gpio_desc *rx_int; struct regulator *reg_vdd, *reg_xceiver; struct clk *clk; bool pll_enable = false; u32 freq = 0; int err; if (!spi->irq) return dev_err_probe(&spi->dev, -ENXIO, "No IRQ specified (maybe node \"interrupts-extended\" in DT missing)!\n"); rx_int = devm_gpiod_get_optional(&spi->dev, "microchip,rx-int", GPIOD_IN); if (IS_ERR(rx_int)) return dev_err_probe(&spi->dev, PTR_ERR(rx_int), "Failed to get RX-INT!\n"); reg_vdd = devm_regulator_get_optional(&spi->dev, "vdd"); if (PTR_ERR(reg_vdd) == -ENODEV) reg_vdd = NULL; else if (IS_ERR(reg_vdd)) return dev_err_probe(&spi->dev, PTR_ERR(reg_vdd), "Failed to get VDD regulator!\n"); reg_xceiver = devm_regulator_get_optional(&spi->dev, "xceiver"); if (PTR_ERR(reg_xceiver) == -ENODEV) reg_xceiver = NULL; else if (IS_ERR(reg_xceiver)) return dev_err_probe(&spi->dev, PTR_ERR(reg_xceiver), "Failed to get Transceiver regulator!\n"); clk = devm_clk_get_optional(&spi->dev, NULL); if (IS_ERR(clk)) return dev_err_probe(&spi->dev, PTR_ERR(clk), "Failed to get Oscillator (clock)!\n"); if (clk) { freq = clk_get_rate(clk); } else { err = device_property_read_u32(&spi->dev, "clock-frequency", &freq); if (err) return dev_err_probe(&spi->dev, err, "Failed to get clock-frequency!\n"); } /* Sanity check */ if (freq < MCP251XFD_SYSCLOCK_HZ_MIN || freq > MCP251XFD_SYSCLOCK_HZ_MAX) { dev_err(&spi->dev, "Oscillator frequency (%u Hz) is too low or high.\n", freq); return -ERANGE; } if (freq <= MCP251XFD_SYSCLOCK_HZ_MAX / MCP251XFD_OSC_PLL_MULTIPLIER) pll_enable = true; ndev = alloc_candev(sizeof(struct mcp251xfd_priv), MCP251XFD_TX_OBJ_NUM_MAX); if (!ndev) return -ENOMEM; SET_NETDEV_DEV(ndev, &spi->dev); ndev->netdev_ops = &mcp251xfd_netdev_ops; ndev->irq = spi->irq; ndev->flags |= IFF_ECHO; priv = netdev_priv(ndev); spi_set_drvdata(spi, priv); priv->can.clock.freq = freq; if (pll_enable) priv->can.clock.freq *= MCP251XFD_OSC_PLL_MULTIPLIER; priv->can.do_set_mode = mcp251xfd_set_mode; priv->can.do_get_berr_counter = mcp251xfd_get_berr_counter; priv->can.bittiming_const = &mcp251xfd_bittiming_const; priv->can.data_bittiming_const = &mcp251xfd_data_bittiming_const; priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_BERR_REPORTING | CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO | CAN_CTRLMODE_CC_LEN8_DLC; set_bit(MCP251XFD_FLAGS_DOWN, priv->flags); priv->ndev = ndev; priv->spi = spi; priv->rx_int = rx_int; priv->clk = clk; priv->pll_enable = pll_enable; priv->reg_vdd = reg_vdd; priv->reg_xceiver = reg_xceiver; match = device_get_match_data(&spi->dev); if (match) priv->devtype_data = *(struct mcp251xfd_devtype_data *)match; else priv->devtype_data = *(struct mcp251xfd_devtype_data *) spi_get_device_id(spi)->driver_data; /* Errata Reference: * mcp2517fd: DS80000792C 5., mcp2518fd: DS80000789C 4. * * The SPI can write corrupted data to the RAM at fast SPI * speeds: * * Simultaneous activity on the CAN bus while writing data to * RAM via the SPI interface, with high SCK frequency, can * lead to corrupted data being written to RAM. * * Fix/Work Around: * Ensure that FSCK is less than or equal to 0.85 * * (FSYSCLK/2). * * Known good combinations are: * * MCP ext-clk SoC SPI SPI-clk max-clk parent-clk config * * 2518 20 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 8333333 Hz 83.33% 600000000 Hz assigned-clocks = <&ccu CLK_SPIx> * 2518 40 MHz allwinner,sun8i-h3 allwinner,sun8i-h3-spi 16666667 Hz 83.33% 600000000 Hz assigned-clocks = <&ccu CLK_SPIx> * 2517 40 MHz atmel,sama5d27 atmel,at91rm9200-spi 16400000 Hz 82.00% 82000000 Hz default * 2518 40 MHz atmel,sama5d27 atmel,at91rm9200-spi 16400000 Hz 82.00% 82000000 Hz default * 2518 40 MHz fsl,imx6dl fsl,imx51-ecspi 15000000 Hz 75.00% 30000000 Hz default * 2517 20 MHz fsl,imx8mm fsl,imx51-ecspi 8333333 Hz 83.33% 16666667 Hz assigned-clocks = <&clk IMX8MM_CLK_ECSPIx_ROOT> * */ priv->spi_max_speed_hz_orig = spi->max_speed_hz; priv->spi_max_speed_hz_slow = min(spi->max_speed_hz, freq / 2 / 1000 * 850); if (priv->pll_enable) priv->spi_max_speed_hz_fast = min(spi->max_speed_hz, freq * MCP251XFD_OSC_PLL_MULTIPLIER / 2 / 1000 * 850); else priv->spi_max_speed_hz_fast = priv->spi_max_speed_hz_slow; spi->max_speed_hz = priv->spi_max_speed_hz_slow; spi->bits_per_word = 8; spi->rt = true; err = spi_setup(spi); if (err) goto out_free_candev; err = mcp251xfd_regmap_init(priv); if (err) goto out_free_candev; err = can_rx_offload_add_manual(ndev, &priv->offload, MCP251XFD_NAPI_WEIGHT); if (err) goto out_free_candev; err = mcp251xfd_register(priv); if (err) { dev_err_probe(&spi->dev, err, "Failed to detect %s.\n", mcp251xfd_get_model_str(priv)); goto out_can_rx_offload_del; } return 0; out_can_rx_offload_del: can_rx_offload_del(&priv->offload); out_free_candev: spi->max_speed_hz = priv->spi_max_speed_hz_orig; free_candev(ndev); return err; } static void mcp251xfd_remove(struct spi_device *spi) { struct mcp251xfd_priv *priv = spi_get_drvdata(spi); struct net_device *ndev = priv->ndev; can_rx_offload_del(&priv->offload); mcp251xfd_unregister(priv); spi->max_speed_hz = priv->spi_max_speed_hz_orig; free_candev(ndev); } static int __maybe_unused mcp251xfd_runtime_suspend(struct device *device) { const struct mcp251xfd_priv *priv = dev_get_drvdata(device); return mcp251xfd_clks_and_vdd_disable(priv); } static int __maybe_unused mcp251xfd_runtime_resume(struct device *device) { const struct mcp251xfd_priv *priv = dev_get_drvdata(device); return mcp251xfd_clks_and_vdd_enable(priv); } static const struct dev_pm_ops mcp251xfd_pm_ops = { SET_RUNTIME_PM_OPS(mcp251xfd_runtime_suspend, mcp251xfd_runtime_resume, NULL) }; static struct spi_driver mcp251xfd_driver = { .driver = { .name = DEVICE_NAME, .pm = &mcp251xfd_pm_ops, .of_match_table = mcp251xfd_of_match, }, .probe = mcp251xfd_probe, .remove = mcp251xfd_remove, .id_table = mcp251xfd_id_table, }; module_spi_driver(mcp251xfd_driver); MODULE_AUTHOR("Marc Kleine-Budde "); MODULE_DESCRIPTION("Microchip MCP251xFD Family CAN controller driver"); MODULE_LICENSE("GPL v2");