diff options
Diffstat (limited to 'drivers/net/pse-pd/realtek-pse-mcu.h')
| -rw-r--r-- | drivers/net/pse-pd/realtek-pse-mcu.h | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/net/pse-pd/realtek-pse-mcu.h b/drivers/net/pse-pd/realtek-pse-mcu.h new file mode 100644 index 000000000..d75e91669 --- /dev/null +++ b/drivers/net/pse-pd/realtek-pse-mcu.h @@ -0,0 +1,94 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _REALTEK_PSE_MCU_H +#define _REALTEK_PSE_MCU_H + +#include <linux/mutex.h> +#include <linux/pse-pd/pse.h> +#include <linux/types.h> + +/* + * Time the MCU itself needs between accepting a request and having a + * response ready. These are properties of the MCU firmware, not of the + * underlying transport: the core paces transactions by RTPSE_MCU_RESPONSE_MS + * and both transports size their per-transaction recv ceiling from + * RTPSE_MCU_RESPONSE_MAX_MS, since some commands are documented as + * needing up to ~1s to produce a reply. + */ +#define RTPSE_MCU_RESPONSE_MS 25 +#define RTPSE_MCU_RESPONSE_MAX_MS 1000 + +/* + * Total time to keep retrying the first MCU read at probe, and the pause + * between attempts. Right after reset-gpios is deasserted the MCU may not + * answer on the bus yet; give it a bounded window to come up before + * declaring the probe failed. + */ +#define RTPSE_MCU_BOOT_TIMEOUT_MS 3000 +#define RTPSE_MCU_BOOT_RETRY_MS 100 + +#define RTPSE_MCU_MSG_SIZE 12 + +struct rtpse_mcu_msg { + u8 opcode; + u8 seq_num; + u8 payload[9]; + u8 checksum; +} __packed; + +/* + * MCU status opcodes (seen on the Gen1 dialect; Gen2 never emits them). + * INCOMPLETE/BAD_CSUM are terminal; NOT_READY is transient. + */ +#define RTPSE_MCU_OPCODE_INCOMPLETE 0xfd /* -EBADE */ +#define RTPSE_MCU_OPCODE_BAD_CSUM 0xfe /* -EBADMSG */ +#define RTPSE_MCU_OPCODE_NOT_READY 0xff /* -EAGAIN */ + +/* + * A polling transport can stop here: the reply to this request (opcode and + * seq_num) or a terminal error. The seq_num rejects a stale normal reply; the + * terminal errors match unconditionally, as a request the MCU couldn't parse + * carries no seq_num to correlate against. + */ +static inline bool rtpse_mcu_resp_is_final(const struct rtpse_mcu_msg *req, + const struct rtpse_mcu_msg *resp) +{ + return (resp->opcode == req->opcode && resp->seq_num == req->seq_num) || + resp->opcode == RTPSE_MCU_OPCODE_INCOMPLETE || + resp->opcode == RTPSE_MCU_OPCODE_BAD_CSUM; +} + +/* Opaque to transports; defined in realtek-pse-mcu-core.c. */ +struct rtpse_mcu_dialect; +struct rtpse_mcu_chip_info; +struct rtpse_mcu_ctrl; + +/* Per-compatible match data (the of_match .data). */ +struct rtpse_mcu_match_data { + const struct rtpse_mcu_dialect *dialect; + bool native_i2c; /* raw-I2C framing (vs SMBus); I2C transport only */ +}; + +struct rtpse_mcu_transport_ops { + int (*send)(struct rtpse_mcu_ctrl *pse, const struct rtpse_mcu_msg *req); + int (*recv)(struct rtpse_mcu_ctrl *pse, const struct rtpse_mcu_msg *req, + struct rtpse_mcu_msg *resp); +}; + +struct rtpse_mcu_ctrl { + struct device *dev; + struct pse_controller_dev pcdev; + struct mutex mutex; /* serializes MCU request/response transactions */ + const struct rtpse_mcu_dialect *dialect; + const struct rtpse_mcu_chip_info *chip; + const struct rtpse_mcu_transport_ops *transport; + u8 seq; /* rolling request seq_num, echoed by the MCU */ +}; + +int rtpse_mcu_register(struct rtpse_mcu_ctrl *pse); + +extern const struct rtpse_mcu_match_data rtpse_mcu_gen1_data; +extern const struct rtpse_mcu_match_data rtpse_mcu_gen2_data; +extern const struct rtpse_mcu_match_data rtpse_mcu_gen2_i2c_data; + +#endif |