^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Microchip / Atmel ECC (I2C) driver.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (c) 2017, Microchip Technology Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Author: Tudor Ambarus <tudor.ambarus@microchip.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/bitrev.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/crc16.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/i2c.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/scatterlist.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/workqueue.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include "atmel-i2c.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) static const struct {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) u8 value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) const char *error_text;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) } error_list[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) { 0x01, "CheckMac or Verify miscompare" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) { 0x03, "Parse Error" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) { 0x05, "ECC Fault" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) { 0x0F, "Execution Error" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) { 0xEE, "Watchdog about to expire" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) { 0xFF, "CRC or other communication error" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * atmel_i2c_checksum() - Generate 16-bit CRC as required by ATMEL ECC.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * CRC16 verification of the count, opcode, param1, param2 and data bytes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * The checksum is saved in little-endian format in the least significant
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) * two bytes of the command. CRC polynomial is 0x8005 and the initial register
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) * value should be zero.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) * @cmd : structure used for communicating with the device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static void atmel_i2c_checksum(struct atmel_i2c_cmd *cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) u8 *data = &cmd->count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) size_t len = cmd->count - CRC_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) __le16 *__crc16 = (__le16 *)(data + len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) *__crc16 = cpu_to_le16(bitrev16(crc16(0, data, len)));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) void atmel_i2c_init_read_cmd(struct atmel_i2c_cmd *cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) cmd->word_addr = COMMAND;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) cmd->opcode = OPCODE_READ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) * Read the word from Configuration zone that contains the lock bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) * (UserExtra, Selector, LockValue, LockConfig).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) cmd->param1 = CONFIG_ZONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) cmd->param2 = cpu_to_le16(DEVICE_LOCK_ADDR);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) cmd->count = READ_COUNT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) atmel_i2c_checksum(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) cmd->msecs = MAX_EXEC_TIME_READ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) cmd->rxsize = READ_RSP_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) EXPORT_SYMBOL(atmel_i2c_init_read_cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) void atmel_i2c_init_random_cmd(struct atmel_i2c_cmd *cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) cmd->word_addr = COMMAND;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) cmd->opcode = OPCODE_RANDOM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) cmd->param1 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) cmd->param2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) cmd->count = RANDOM_COUNT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) atmel_i2c_checksum(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) cmd->msecs = MAX_EXEC_TIME_RANDOM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) cmd->rxsize = RANDOM_RSP_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) EXPORT_SYMBOL(atmel_i2c_init_random_cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) void atmel_i2c_init_genkey_cmd(struct atmel_i2c_cmd *cmd, u16 keyid)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) cmd->word_addr = COMMAND;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) cmd->count = GENKEY_COUNT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) cmd->opcode = OPCODE_GENKEY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) cmd->param1 = GENKEY_MODE_PRIVATE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) /* a random private key will be generated and stored in slot keyID */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) cmd->param2 = cpu_to_le16(keyid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) atmel_i2c_checksum(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) cmd->msecs = MAX_EXEC_TIME_GENKEY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) cmd->rxsize = GENKEY_RSP_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) EXPORT_SYMBOL(atmel_i2c_init_genkey_cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) int atmel_i2c_init_ecdh_cmd(struct atmel_i2c_cmd *cmd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) struct scatterlist *pubkey)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) size_t copied;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) cmd->word_addr = COMMAND;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) cmd->count = ECDH_COUNT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) cmd->opcode = OPCODE_ECDH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) cmd->param1 = ECDH_PREFIX_MODE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) /* private key slot */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) cmd->param2 = cpu_to_le16(DATA_SLOT_2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) * The device only supports NIST P256 ECC keys. The public key size will
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) * always be the same. Use a macro for the key size to avoid unnecessary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) * computations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) copied = sg_copy_to_buffer(pubkey,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) sg_nents_for_len(pubkey,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) ATMEL_ECC_PUBKEY_SIZE),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) cmd->data, ATMEL_ECC_PUBKEY_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) if (copied != ATMEL_ECC_PUBKEY_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) atmel_i2c_checksum(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) cmd->msecs = MAX_EXEC_TIME_ECDH;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) cmd->rxsize = ECDH_RSP_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) EXPORT_SYMBOL(atmel_i2c_init_ecdh_cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) * After wake and after execution of a command, there will be error, status, or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) * result bytes in the device's output register that can be retrieved by the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) * system. When the length of that group is four bytes, the codes returned are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) * detailed in error_list.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) static int atmel_i2c_status(struct device *dev, u8 *status)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) size_t err_list_len = ARRAY_SIZE(error_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) u8 err_id = status[1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) if (*status != STATUS_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) if (err_id == STATUS_WAKE_SUCCESSFUL || err_id == STATUS_NOERR)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) for (i = 0; i < err_list_len; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) if (error_list[i].value == err_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) /* if err_id is not in the error_list then ignore it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) if (i != err_list_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) dev_err(dev, "%02x: %s:\n", err_id, error_list[i].error_text);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) return err_id;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) static int atmel_i2c_wakeup(struct i2c_client *client)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) struct atmel_i2c_client_priv *i2c_priv = i2c_get_clientdata(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) u8 status[STATUS_RSP_SIZE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) * The device ignores any levels or transitions on the SCL pin when the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) * device is idle, asleep or during waking up. Don't check for error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) * when waking up the device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) i2c_transfer_buffer_flags(client, i2c_priv->wake_token,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) i2c_priv->wake_token_sz, I2C_M_IGNORE_NAK);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) * Wait to wake the device. Typical execution times for ecdh and genkey
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) * are around tens of milliseconds. Delta is chosen to 50 microseconds.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) usleep_range(TWHI_MIN, TWHI_MAX);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) ret = i2c_master_recv(client, status, STATUS_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) return atmel_i2c_status(&client->dev, status);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) static int atmel_i2c_sleep(struct i2c_client *client)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) u8 sleep = SLEEP_TOKEN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) return i2c_master_send(client, &sleep, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) * atmel_i2c_send_receive() - send a command to the device and receive its
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) * response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) * @client: i2c client device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) * @cmd : structure used to communicate with the device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) * After the device receives a Wake token, a watchdog counter starts within the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) * device. After the watchdog timer expires, the device enters sleep mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) * regardless of whether some I/O transmission or command execution is in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) * progress. If a command is attempted when insufficient time remains prior to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) * watchdog timer execution, the device will return the watchdog timeout error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) * code without attempting to execute the command. There is no way to reset the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) * counter other than to put the device into sleep or idle mode and then
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) * wake it up again.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) int atmel_i2c_send_receive(struct i2c_client *client, struct atmel_i2c_cmd *cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) struct atmel_i2c_client_priv *i2c_priv = i2c_get_clientdata(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) mutex_lock(&i2c_priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) ret = atmel_i2c_wakeup(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) /* send the command */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) ret = i2c_master_send(client, (u8 *)cmd, cmd->count + WORD_ADDR_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) /* delay the appropriate amount of time for command to execute */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) msleep(cmd->msecs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) /* receive the response */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) ret = i2c_master_recv(client, cmd->data, cmd->rxsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) /* put the device into low-power mode */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) ret = atmel_i2c_sleep(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) mutex_unlock(&i2c_priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) return atmel_i2c_status(&client->dev, cmd->data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) mutex_unlock(&i2c_priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) EXPORT_SYMBOL(atmel_i2c_send_receive);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) static void atmel_i2c_work_handler(struct work_struct *work)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) struct atmel_i2c_work_data *work_data =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) container_of(work, struct atmel_i2c_work_data, work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) struct atmel_i2c_cmd *cmd = &work_data->cmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) struct i2c_client *client = work_data->client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) int status;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) status = atmel_i2c_send_receive(client, cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) work_data->cbk(work_data, work_data->areq, status);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) void atmel_i2c_enqueue(struct atmel_i2c_work_data *work_data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) void (*cbk)(struct atmel_i2c_work_data *work_data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) void *areq, int status),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) void *areq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) work_data->cbk = (void *)cbk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) work_data->areq = areq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) INIT_WORK(&work_data->work, atmel_i2c_work_handler);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) schedule_work(&work_data->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) EXPORT_SYMBOL(atmel_i2c_enqueue);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) static inline size_t atmel_i2c_wake_token_sz(u32 bus_clk_rate)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) u32 no_of_bits = DIV_ROUND_UP(TWLO_USEC * bus_clk_rate, USEC_PER_SEC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) /* return the size of the wake_token in bytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) return DIV_ROUND_UP(no_of_bits, 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) static int device_sanity_check(struct i2c_client *client)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) struct atmel_i2c_cmd *cmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) if (!cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) atmel_i2c_init_read_cmd(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) ret = atmel_i2c_send_receive(client, cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) goto free_cmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) * It is vital that the Configuration, Data and OTP zones be locked
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) * prior to release into the field of the system containing the device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) * Failure to lock these zones may permit modification of any secret
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) * keys and may lead to other security problems.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) if (cmd->data[LOCK_CONFIG_IDX] || cmd->data[LOCK_VALUE_IDX]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) dev_err(&client->dev, "Configuration or Data and OTP zones are unlocked!\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) ret = -ENOTSUPP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) free_cmd:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) kfree(cmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) int atmel_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) struct atmel_i2c_client_priv *i2c_priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) struct device *dev = &client->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) u32 bus_clk_rate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) dev_err(dev, "I2C_FUNC_I2C not supported\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) bus_clk_rate = i2c_acpi_find_bus_speed(&client->adapter->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) if (!bus_clk_rate) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) ret = device_property_read_u32(&client->adapter->dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) "clock-frequency", &bus_clk_rate);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) dev_err(dev, "failed to read clock-frequency property\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) if (bus_clk_rate > 1000000L) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) dev_err(dev, "%d exceeds maximum supported clock frequency (1MHz)\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) bus_clk_rate);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) i2c_priv = devm_kmalloc(dev, sizeof(*i2c_priv), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) if (!i2c_priv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) i2c_priv->client = client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) mutex_init(&i2c_priv->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) * WAKE_TOKEN_MAX_SIZE was calculated for the maximum bus_clk_rate -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) * 1MHz. The previous bus_clk_rate check ensures us that wake_token_sz
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) * will always be smaller than or equal to WAKE_TOKEN_MAX_SIZE.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) i2c_priv->wake_token_sz = atmel_i2c_wake_token_sz(bus_clk_rate);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) memset(i2c_priv->wake_token, 0, sizeof(i2c_priv->wake_token));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) atomic_set(&i2c_priv->tfm_count, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) i2c_set_clientdata(client, i2c_priv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) ret = device_sanity_check(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) EXPORT_SYMBOL(atmel_i2c_probe);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) MODULE_AUTHOR("Tudor Ambarus <tudor.ambarus@microchip.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) MODULE_DESCRIPTION("Microchip / Atmel ECC (I2C) driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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