diff options
Diffstat (limited to 'drivers/char/tpm/tpm_tis_synquacer.c')
-rw-r--r-- | drivers/char/tpm/tpm_tis_synquacer.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_tis_synquacer.c b/drivers/char/tpm/tpm_tis_synquacer.c new file mode 100644 index 000000000..679196c61 --- /dev/null +++ b/drivers/char/tpm/tpm_tis_synquacer.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Linaro Ltd. + * + * This device driver implements MMIO TPM on SynQuacer Platform. + */ +#include <linux/acpi.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/kernel.h> +#include "tpm.h" +#include "tpm_tis_core.h" + +/* + * irq > 0 means: use irq $irq; + * irq = 0 means: autoprobe for an irq; + * irq = -1 means: no irq support + */ +struct tpm_tis_synquacer_info { + struct resource res; + int irq; +}; + +struct tpm_tis_synquacer_phy { + struct tpm_tis_data priv; + void __iomem *iobase; +}; + +static inline struct tpm_tis_synquacer_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data) +{ + return container_of(data, struct tpm_tis_synquacer_phy, priv); +} + +static int tpm_tis_synquacer_read_bytes(struct tpm_tis_data *data, u32 addr, + u16 len, u8 *result, + enum tpm_tis_io_mode io_mode) +{ + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data); + switch (io_mode) { + case TPM_TIS_PHYS_8: + while (len--) + *result++ = ioread8(phy->iobase + addr); + break; + case TPM_TIS_PHYS_16: + result[1] = ioread8(phy->iobase + addr + 1); + result[0] = ioread8(phy->iobase + addr); + break; + case TPM_TIS_PHYS_32: + result[3] = ioread8(phy->iobase + addr + 3); + result[2] = ioread8(phy->iobase + addr + 2); + result[1] = ioread8(phy->iobase + addr + 1); + result[0] = ioread8(phy->iobase + addr); + break; + } + + return 0; +} + +static int tpm_tis_synquacer_write_bytes(struct tpm_tis_data *data, u32 addr, + u16 len, const u8 *value, + enum tpm_tis_io_mode io_mode) +{ + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data); + switch (io_mode) { + case TPM_TIS_PHYS_8: + while (len--) + iowrite8(*value++, phy->iobase + addr); + break; + case TPM_TIS_PHYS_16: + return -EINVAL; + case TPM_TIS_PHYS_32: + /* + * Due to the limitation of SPI controller on SynQuacer, + * 16/32 bits access must be done in byte-wise and descending order. + */ + iowrite8(value[3], phy->iobase + addr + 3); + iowrite8(value[2], phy->iobase + addr + 2); + iowrite8(value[1], phy->iobase + addr + 1); + iowrite8(value[0], phy->iobase + addr); + break; + } + + return 0; +} + +static const struct tpm_tis_phy_ops tpm_tcg_bw = { + .read_bytes = tpm_tis_synquacer_read_bytes, + .write_bytes = tpm_tis_synquacer_write_bytes, +}; + +static int tpm_tis_synquacer_init(struct device *dev, + struct tpm_tis_synquacer_info *tpm_info) +{ + struct tpm_tis_synquacer_phy *phy; + + phy = devm_kzalloc(dev, sizeof(struct tpm_tis_synquacer_phy), GFP_KERNEL); + if (phy == NULL) + return -ENOMEM; + + phy->iobase = devm_ioremap_resource(dev, &tpm_info->res); + if (IS_ERR(phy->iobase)) + return PTR_ERR(phy->iobase); + + return tpm_tis_core_init(dev, &phy->priv, tpm_info->irq, &tpm_tcg_bw, + ACPI_HANDLE(dev)); +} + +static SIMPLE_DEV_PM_OPS(tpm_tis_synquacer_pm, tpm_pm_suspend, tpm_tis_resume); + +static int tpm_tis_synquacer_probe(struct platform_device *pdev) +{ + struct tpm_tis_synquacer_info tpm_info = {}; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(&pdev->dev, "no memory resource defined\n"); + return -ENODEV; + } + tpm_info.res = *res; + + tpm_info.irq = -1; + + return tpm_tis_synquacer_init(&pdev->dev, &tpm_info); +} + +static int tpm_tis_synquacer_remove(struct platform_device *pdev) +{ + struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); + + tpm_chip_unregister(chip); + tpm_tis_remove(chip); + + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id tis_synquacer_of_platform_match[] = { + {.compatible = "socionext,synquacer-tpm-mmio"}, + {}, +}; +MODULE_DEVICE_TABLE(of, tis_synquacer_of_platform_match); +#endif + +#ifdef CONFIG_ACPI +static const struct acpi_device_id tpm_synquacer_acpi_tbl[] = { + { "SCX0009" }, + {}, +}; +MODULE_DEVICE_TABLE(acpi, tpm_synquacer_acpi_tbl); +#endif + +static struct platform_driver tis_synquacer_drv = { + .probe = tpm_tis_synquacer_probe, + .remove = tpm_tis_synquacer_remove, + .driver = { + .name = "tpm_tis_synquacer", + .pm = &tpm_tis_synquacer_pm, + .of_match_table = of_match_ptr(tis_synquacer_of_platform_match), + .acpi_match_table = ACPI_PTR(tpm_synquacer_acpi_tbl), + }, +}; + +static int __init tpm_tis_synquacer_module_init(void) +{ + int rc; + + rc = platform_driver_register(&tis_synquacer_drv); + if (rc) + return rc; + + return 0; +} + +static void __exit tpm_tis_synquacer_module_exit(void) +{ + platform_driver_unregister(&tis_synquacer_drv); +} + +module_init(tpm_tis_synquacer_module_init); +module_exit(tpm_tis_synquacer_module_exit); +MODULE_DESCRIPTION("TPM MMIO Driver for Socionext SynQuacer platform"); +MODULE_LICENSE("GPL"); |