diff options
Diffstat (limited to 'drivers/char/tpm/st33zp24/spi.c')
| -rw-r--r-- | drivers/char/tpm/st33zp24/spi.c | 184 |
1 files changed, 108 insertions, 76 deletions
diff --git a/drivers/char/tpm/st33zp24/spi.c b/drivers/char/tpm/st33zp24/spi.c index f974c945c97a..9f5a0117098c 100644 --- a/drivers/char/tpm/st33zp24/spi.c +++ b/drivers/char/tpm/st33zp24/spi.c @@ -1,6 +1,6 @@ /* * STMicroelectronics TPM SPI Linux driver for TPM ST33ZP24 - * Copyright (C) 2009 - 2015 STMicroelectronics + * Copyright (C) 2009 - 2016 STMicroelectronics * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -19,11 +19,14 @@ #include <linux/module.h> #include <linux/spi/spi.h> #include <linux/gpio.h> +#include <linux/gpio/consumer.h> #include <linux/of_irq.h> #include <linux/of_gpio.h> +#include <linux/acpi.h> #include <linux/tpm.h> #include <linux/platform_data/st33zp24.h> +#include "../tpm.h" #include "st33zp24.h" #define TPM_DATA_FIFO 0x24 @@ -66,7 +69,7 @@ struct st33zp24_spi_phy { struct spi_device *spi_device; - struct spi_transfer spi_xfer; + u8 tx_buf[ST33ZP24_SPI_BUFFER_SIZE]; u8 rx_buf[ST33ZP24_SPI_BUFFER_SIZE]; @@ -110,43 +113,39 @@ static int st33zp24_status_to_errno(u8 code) static int st33zp24_spi_send(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size) { - u8 data = 0; - int total_length = 0, nbr_dummy_bytes = 0, ret = 0; + int total_length = 0, ret = 0; struct st33zp24_spi_phy *phy = phy_id; struct spi_device *dev = phy->spi_device; - u8 *tx_buf = (u8 *)phy->spi_xfer.tx_buf; - u8 *rx_buf = phy->spi_xfer.rx_buf; + struct spi_transfer spi_xfer = { + .tx_buf = phy->tx_buf, + .rx_buf = phy->rx_buf, + }; /* Pre-Header */ - data = TPM_WRITE_DIRECTION | LOCALITY0; - memcpy(tx_buf + total_length, &data, sizeof(data)); - total_length++; - data = tpm_register; - memcpy(tx_buf + total_length, &data, sizeof(data)); - total_length++; + phy->tx_buf[total_length++] = TPM_WRITE_DIRECTION | LOCALITY0; + phy->tx_buf[total_length++] = tpm_register; if (tpm_size > 0 && tpm_register == TPM_DATA_FIFO) { - tx_buf[total_length++] = tpm_size >> 8; - tx_buf[total_length++] = tpm_size; + phy->tx_buf[total_length++] = tpm_size >> 8; + phy->tx_buf[total_length++] = tpm_size; } - memcpy(&tx_buf[total_length], tpm_data, tpm_size); + memcpy(&phy->tx_buf[total_length], tpm_data, tpm_size); total_length += tpm_size; - nbr_dummy_bytes = phy->latency; - memset(&tx_buf[total_length], TPM_DUMMY_BYTE, nbr_dummy_bytes); + memset(&phy->tx_buf[total_length], TPM_DUMMY_BYTE, phy->latency); - phy->spi_xfer.len = total_length + nbr_dummy_bytes; + spi_xfer.len = total_length + phy->latency; - ret = spi_sync_transfer(dev, &phy->spi_xfer, 1); + ret = spi_sync_transfer(dev, &spi_xfer, 1); if (ret == 0) - ret = rx_buf[total_length + nbr_dummy_bytes - 1]; + ret = phy->rx_buf[total_length + phy->latency - 1]; return st33zp24_status_to_errno(ret); } /* st33zp24_spi_send() */ /* - * read8_recv + * st33zp24_spi_read8_recv * Recv byte from the TIS register according to the ST33ZP24 SPI protocol. * @param: phy_id, the phy description * @param: tpm_register, the tpm tis register where the data should be read @@ -154,40 +153,37 @@ static int st33zp24_spi_send(void *phy_id, u8 tpm_register, u8 *tpm_data, * @param: tpm_size, tpm TPM response size to read. * @return: should be zero if success else a negative error code. */ -static int read8_reg(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size) +static int st33zp24_spi_read8_reg(void *phy_id, u8 tpm_register, u8 *tpm_data, + int tpm_size) { - u8 data = 0; - int total_length = 0, nbr_dummy_bytes, ret; + int total_length = 0, ret; struct st33zp24_spi_phy *phy = phy_id; struct spi_device *dev = phy->spi_device; - u8 *tx_buf = (u8 *)phy->spi_xfer.tx_buf; - u8 *rx_buf = phy->spi_xfer.rx_buf; + struct spi_transfer spi_xfer = { + .tx_buf = phy->tx_buf, + .rx_buf = phy->rx_buf, + }; /* Pre-Header */ - data = LOCALITY0; - memcpy(tx_buf + total_length, &data, sizeof(data)); - total_length++; - data = tpm_register; - memcpy(tx_buf + total_length, &data, sizeof(data)); - total_length++; + phy->tx_buf[total_length++] = LOCALITY0; + phy->tx_buf[total_length++] = tpm_register; - nbr_dummy_bytes = phy->latency; - memset(&tx_buf[total_length], TPM_DUMMY_BYTE, - nbr_dummy_bytes + tpm_size); + memset(&phy->tx_buf[total_length], TPM_DUMMY_BYTE, + phy->latency + tpm_size); - phy->spi_xfer.len = total_length + nbr_dummy_bytes + tpm_size; + spi_xfer.len = total_length + phy->latency + tpm_size; /* header + status byte + size of the data + status byte */ - ret = spi_sync_transfer(dev, &phy->spi_xfer, 1); + ret = spi_sync_transfer(dev, &spi_xfer, 1); if (tpm_size > 0 && ret == 0) { - ret = rx_buf[total_length + nbr_dummy_bytes - 1]; + ret = phy->rx_buf[total_length + phy->latency - 1]; - memcpy(tpm_data, rx_buf + total_length + nbr_dummy_bytes, + memcpy(tpm_data, phy->rx_buf + total_length + phy->latency, tpm_size); } return ret; -} /* read8_reg() */ +} /* st33zp24_spi_read8_reg() */ /* * st33zp24_spi_recv @@ -203,13 +199,13 @@ static int st33zp24_spi_recv(void *phy_id, u8 tpm_register, u8 *tpm_data, { int ret; - ret = read8_reg(phy_id, tpm_register, tpm_data, tpm_size); + ret = st33zp24_spi_read8_reg(phy_id, tpm_register, tpm_data, tpm_size); if (!st33zp24_status_to_errno(ret)) return tpm_size; return ret; } /* st33zp24_spi_recv() */ -static int evaluate_latency(void *phy_id) +static int st33zp24_spi_evaluate_latency(void *phy_id) { struct st33zp24_spi_phy *phy = phy_id; int latency = 1, status = 0; @@ -217,9 +213,15 @@ static int evaluate_latency(void *phy_id) while (!status && latency < MAX_SPI_LATENCY) { phy->latency = latency; - status = read8_reg(phy_id, TPM_INTF_CAPABILITY, &data, 1); + status = st33zp24_spi_read8_reg(phy_id, TPM_INTF_CAPABILITY, + &data, 1); latency++; } + if (status < 0) + return status; + if (latency == MAX_SPI_LATENCY) + return -ENODEV; + return latency - 1; } /* evaluate_latency() */ @@ -228,24 +230,52 @@ static const struct st33zp24_phy_ops spi_phy_ops = { .recv = st33zp24_spi_recv, }; -#ifdef CONFIG_OF -static int tpm_stm_spi_of_request_resources(struct st33zp24_spi_phy *phy) +static int st33zp24_spi_acpi_request_resources(struct spi_device *spi_dev) { + struct tpm_chip *chip = spi_get_drvdata(spi_dev); + struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev); + struct st33zp24_spi_phy *phy = tpm_dev->phy_id; + struct gpio_desc *gpiod_lpcpd; + struct device *dev = &spi_dev->dev; + + /* Get LPCPD GPIO from ACPI */ + gpiod_lpcpd = devm_gpiod_get_index(dev, "TPM IO LPCPD", 1, + GPIOD_OUT_HIGH); + if (IS_ERR(gpiod_lpcpd)) { + dev_err(dev, "Failed to retrieve lpcpd-gpios from acpi.\n"); + phy->io_lpcpd = -1; + /* + * lpcpd pin is not specified. This is not an issue as + * power management can be also managed by TPM specific + * commands. So leave with a success status code. + */ + return 0; + } + + phy->io_lpcpd = desc_to_gpio(gpiod_lpcpd); + + return 0; +} + +static int st33zp24_spi_of_request_resources(struct spi_device *spi_dev) +{ + struct tpm_chip *chip = spi_get_drvdata(spi_dev); + struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev); + struct st33zp24_spi_phy *phy = tpm_dev->phy_id; struct device_node *pp; - struct spi_device *dev = phy->spi_device; int gpio; int ret; - pp = dev->dev.of_node; + pp = spi_dev->dev.of_node; if (!pp) { - dev_err(&dev->dev, "No platform data\n"); + dev_err(&spi_dev->dev, "No platform data\n"); return -ENODEV; } /* Get GPIO from device tree */ gpio = of_get_named_gpio(pp, "lpcpd-gpios", 0); if (gpio < 0) { - dev_err(&dev->dev, + dev_err(&spi_dev->dev, "Failed to retrieve lpcpd-gpios from dts.\n"); phy->io_lpcpd = -1; /* @@ -256,26 +286,22 @@ static int tpm_stm_spi_of_request_resources(struct st33zp24_spi_phy *phy) return 0; } /* GPIO request and configuration */ - ret = devm_gpio_request_one(&dev->dev, gpio, + ret = devm_gpio_request_one(&spi_dev->dev, gpio, GPIOF_OUT_INIT_HIGH, "TPM IO LPCPD"); if (ret) { - dev_err(&dev->dev, "Failed to request lpcpd pin\n"); + dev_err(&spi_dev->dev, "Failed to request lpcpd pin\n"); return -ENODEV; } phy->io_lpcpd = gpio; return 0; } -#else -static int tpm_stm_spi_of_request_resources(struct st33zp24_spi_phy *phy) -{ - return -ENODEV; -} -#endif -static int tpm_stm_spi_request_resources(struct spi_device *dev, - struct st33zp24_spi_phy *phy) +static int st33zp24_spi_request_resources(struct spi_device *dev) { + struct tpm_chip *chip = spi_get_drvdata(dev); + struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev); + struct st33zp24_spi_phy *phy = tpm_dev->phy_id; struct st33zp24_platform_data *pdata; int ret; @@ -303,13 +329,12 @@ static int tpm_stm_spi_request_resources(struct spi_device *dev, } /* - * tpm_st33_spi_probe initialize the TPM device + * st33zp24_spi_probe initialize the TPM device * @param: dev, the spi_device drescription (TPM SPI description). * @return: 0 in case of success. * or a negative value describing the error. */ -static int -tpm_st33_spi_probe(struct spi_device *dev) +static int st33zp24_spi_probe(struct spi_device *dev) { int ret; struct st33zp24_platform_data *pdata; @@ -328,21 +353,23 @@ tpm_st33_spi_probe(struct spi_device *dev) return -ENOMEM; phy->spi_device = dev; + pdata = dev->dev.platform_data; if (!pdata && dev->dev.of_node) { - ret = tpm_stm_spi_of_request_resources(phy); + ret = st33zp24_spi_of_request_resources(dev); if (ret) return ret; } else if (pdata) { - ret = tpm_stm_spi_request_resources(dev, phy); + ret = st33zp24_spi_request_resources(dev); + if (ret) + return ret; + } else if (ACPI_HANDLE(&dev->dev)) { + ret = st33zp24_spi_acpi_request_resources(dev); if (ret) return ret; } - phy->spi_xfer.tx_buf = phy->tx_buf; - phy->spi_xfer.rx_buf = phy->rx_buf; - - phy->latency = evaluate_latency(phy); + phy->latency = st33zp24_spi_evaluate_latency(phy); if (phy->latency <= 0) return -ENODEV; @@ -351,11 +378,11 @@ tpm_st33_spi_probe(struct spi_device *dev) } /* - * tpm_st33_spi_remove remove the TPM device + * st33zp24_spi_remove remove the TPM device * @param: client, the spi_device drescription (TPM SPI description). * @return: 0 in case of success. */ -static int tpm_st33_spi_remove(struct spi_device *dev) +static int st33zp24_spi_remove(struct spi_device *dev) { struct tpm_chip *chip = spi_get_drvdata(dev); @@ -368,29 +395,34 @@ static const struct spi_device_id st33zp24_spi_id[] = { }; MODULE_DEVICE_TABLE(spi, st33zp24_spi_id); -#ifdef CONFIG_OF static const struct of_device_id of_st33zp24_spi_match[] = { { .compatible = "st,st33zp24-spi", }, {} }; MODULE_DEVICE_TABLE(of, of_st33zp24_spi_match); -#endif + +static const struct acpi_device_id st33zp24_spi_acpi_match[] = { + {"SMO3324"}, + {} +}; +MODULE_DEVICE_TABLE(acpi, st33zp24_spi_acpi_match); static SIMPLE_DEV_PM_OPS(st33zp24_spi_ops, st33zp24_pm_suspend, st33zp24_pm_resume); -static struct spi_driver tpm_st33_spi_driver = { +static struct spi_driver st33zp24_spi_driver = { .driver = { .name = TPM_ST33_SPI, .pm = &st33zp24_spi_ops, .of_match_table = of_match_ptr(of_st33zp24_spi_match), + .acpi_match_table = ACPI_PTR(st33zp24_spi_acpi_match), }, - .probe = tpm_st33_spi_probe, - .remove = tpm_st33_spi_remove, + .probe = st33zp24_spi_probe, + .remove = st33zp24_spi_remove, .id_table = st33zp24_spi_id, }; -module_spi_driver(tpm_st33_spi_driver); +module_spi_driver(st33zp24_spi_driver); MODULE_AUTHOR("TPM support (TPMsupport@list.st.com)"); MODULE_DESCRIPTION("STM TPM 1.2 SPI ST33 Driver"); |