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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 | // SPDX-License-Identifier: GPL-2.0-or-later /* * STMicroelectronics TPM I2C Linux driver for TPM ST33ZP24 * Copyright (C) 2009 - 2016 STMicroelectronics */ #include <linux/module.h> #include <linux/i2c.h> #include <linux/of.h> #include <linux/acpi.h> #include <linux/tpm.h> #include "../tpm.h" #include "st33zp24.h" #define TPM_DUMMY_BYTE 0xAA struct st33zp24_i2c_phy { struct i2c_client *client; u8 buf[ST33ZP24_BUFSIZE + 1]; }; /* * write8_reg * Send byte to the TIS register according to the ST33ZP24 I2C protocol. * @param: tpm_register, the tpm tis register where the data should be written * @param: tpm_data, the tpm_data to write inside the tpm_register * @param: tpm_size, The length of the data * @return: Returns negative errno, or else the number of bytes written. */ static int write8_reg(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size) { struct st33zp24_i2c_phy *phy = phy_id; phy->buf[0] = tpm_register; memcpy(phy->buf + 1, tpm_data, tpm_size); return i2c_master_send(phy->client, phy->buf, tpm_size + 1); } /* write8_reg() */ /* * read8_reg * Recv byte from the TIS register according to the ST33ZP24 I2C protocol. * @param: tpm_register, the tpm tis register where the data should be read * @param: tpm_data, the TPM response * @param: tpm_size, tpm TPM response size to read. * @return: number of byte read successfully: should be one if success. */ static int read8_reg(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size) { struct st33zp24_i2c_phy *phy = phy_id; u8 status = 0; u8 data; data = TPM_DUMMY_BYTE; status = write8_reg(phy, tpm_register, &data, 1); if (status == 2) status = i2c_master_recv(phy->client, tpm_data, tpm_size); return status; } /* read8_reg() */ /* * st33zp24_i2c_send * Send byte to the TIS register according to the ST33ZP24 I2C protocol. * @param: phy_id, the phy description * @param: tpm_register, the tpm tis register where the data should be written * @param: tpm_data, the tpm_data to write inside the tpm_register * @param: tpm_size, the length of the data * @return: number of byte written successfully: should be one if success. */ static int st33zp24_i2c_send(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size) { return write8_reg(phy_id, tpm_register | TPM_WRITE_DIRECTION, tpm_data, tpm_size); } /* * st33zp24_i2c_recv * Recv byte from the TIS register according to the ST33ZP24 I2C protocol. * @param: phy_id, the phy description * @param: tpm_register, the tpm tis register where the data should be read * @param: tpm_data, the TPM response * @param: tpm_size, tpm TPM response size to read. * @return: number of byte read successfully: should be one if success. */ static int st33zp24_i2c_recv(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size) { return read8_reg(phy_id, tpm_register, tpm_data, tpm_size); } static const struct st33zp24_phy_ops i2c_phy_ops = { .send = st33zp24_i2c_send, .recv = st33zp24_i2c_recv, }; /* * st33zp24_i2c_probe initialize the TPM device * @param: client, the i2c_client description (TPM I2C description). * @param: id, the i2c_device_id struct. * @return: 0 in case of success. * -1 in other case. */ static int st33zp24_i2c_probe(struct i2c_client *client) { struct st33zp24_i2c_phy *phy; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { dev_info(&client->dev, "client not i2c capable\n"); return -ENODEV; } phy = devm_kzalloc(&client->dev, sizeof(struct st33zp24_i2c_phy), GFP_KERNEL); if (!phy) return -ENOMEM; phy->client = client; return st33zp24_probe(phy, &i2c_phy_ops, &client->dev, client->irq); } /* * st33zp24_i2c_remove remove the TPM device * @param: client, the i2c_client description (TPM I2C description). * @return: 0 in case of success. */ static void st33zp24_i2c_remove(struct i2c_client *client) { struct tpm_chip *chip = i2c_get_clientdata(client); st33zp24_remove(chip); } static const struct i2c_device_id st33zp24_i2c_id[] = { {TPM_ST33_I2C, 0}, {} }; MODULE_DEVICE_TABLE(i2c, st33zp24_i2c_id); static const struct of_device_id of_st33zp24_i2c_match[] = { { .compatible = "st,st33zp24-i2c", }, {} }; MODULE_DEVICE_TABLE(of, of_st33zp24_i2c_match); static const struct acpi_device_id st33zp24_i2c_acpi_match[] = { {"SMO3324"}, {} }; MODULE_DEVICE_TABLE(acpi, st33zp24_i2c_acpi_match); static SIMPLE_DEV_PM_OPS(st33zp24_i2c_ops, st33zp24_pm_suspend, st33zp24_pm_resume); static struct i2c_driver st33zp24_i2c_driver = { .driver = { .name = TPM_ST33_I2C, .pm = &st33zp24_i2c_ops, .of_match_table = of_match_ptr(of_st33zp24_i2c_match), .acpi_match_table = ACPI_PTR(st33zp24_i2c_acpi_match), }, .probe_new = st33zp24_i2c_probe, .remove = st33zp24_i2c_remove, .id_table = st33zp24_i2c_id }; module_i2c_driver(st33zp24_i2c_driver); MODULE_AUTHOR("TPM support (TPMsupport@list.st.com)"); MODULE_DESCRIPTION("STM TPM 1.2 I2C ST33 Driver"); MODULE_VERSION("1.3.0"); MODULE_LICENSE("GPL"); |