1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2020 Linaro Ltd. 4 * 5 * This device driver implements MMIO TPM on SynQuacer Platform. 6 */ 7 #include <linux/acpi.h> 8 #include <linux/init.h> 9 #include <linux/module.h> 10 #include <linux/slab.h> 11 #include <linux/of.h> 12 #include <linux/kernel.h> 13 #include "tpm.h" 14 #include "tpm_tis_core.h" 15 16 /* 17 * irq > 0 means: use irq $irq; 18 * irq = 0 means: autoprobe for an irq; 19 * irq = -1 means: no irq support 20 */ 21 struct tpm_tis_synquacer_info { 22 struct resource res; 23 int irq; 24 }; 25 26 struct tpm_tis_synquacer_phy { 27 struct tpm_tis_data priv; 28 void __iomem *iobase; 29 }; 30 31 static inline struct tpm_tis_synquacer_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data) 32 { 33 return container_of(data, struct tpm_tis_synquacer_phy, priv); 34 } 35 36 static int tpm_tis_synquacer_read_bytes(struct tpm_tis_data *data, u32 addr, 37 u16 len, u8 *result, 38 enum tpm_tis_io_mode io_mode) 39 { 40 struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data); 41 switch (io_mode) { 42 case TPM_TIS_PHYS_8: 43 while (len--) 44 *result++ = ioread8(phy->iobase + addr); 45 break; 46 case TPM_TIS_PHYS_16: 47 result[1] = ioread8(phy->iobase + addr + 1); 48 result[0] = ioread8(phy->iobase + addr); 49 break; 50 case TPM_TIS_PHYS_32: 51 result[3] = ioread8(phy->iobase + addr + 3); 52 result[2] = ioread8(phy->iobase + addr + 2); 53 result[1] = ioread8(phy->iobase + addr + 1); 54 result[0] = ioread8(phy->iobase + addr); 55 break; 56 } 57 58 return 0; 59 } 60 61 static int tpm_tis_synquacer_write_bytes(struct tpm_tis_data *data, u32 addr, 62 u16 len, const u8 *value, 63 enum tpm_tis_io_mode io_mode) 64 { 65 struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data); 66 switch (io_mode) { 67 case TPM_TIS_PHYS_8: 68 while (len--) 69 iowrite8(*value++, phy->iobase + addr); 70 break; 71 case TPM_TIS_PHYS_16: 72 return -EINVAL; 73 case TPM_TIS_PHYS_32: 74 /* 75 * Due to the limitation of SPI controller on SynQuacer, 76 * 16/32 bits access must be done in byte-wise and descending order. 77 */ 78 iowrite8(value[3], phy->iobase + addr + 3); 79 iowrite8(value[2], phy->iobase + addr + 2); 80 iowrite8(value[1], phy->iobase + addr + 1); 81 iowrite8(value[0], phy->iobase + addr); 82 break; 83 } 84 85 return 0; 86 } 87 88 static const struct tpm_tis_phy_ops tpm_tcg_bw = { 89 .read_bytes = tpm_tis_synquacer_read_bytes, 90 .write_bytes = tpm_tis_synquacer_write_bytes, 91 }; 92 93 static int tpm_tis_synquacer_init(struct device *dev, 94 struct tpm_tis_synquacer_info *tpm_info) 95 { 96 struct tpm_tis_synquacer_phy *phy; 97 98 phy = devm_kzalloc(dev, sizeof(struct tpm_tis_synquacer_phy), GFP_KERNEL); 99 if (phy == NULL) 100 return -ENOMEM; 101 102 phy->iobase = devm_ioremap_resource(dev, &tpm_info->res); 103 if (IS_ERR(phy->iobase)) 104 return PTR_ERR(phy->iobase); 105 106 return tpm_tis_core_init(dev, &phy->priv, tpm_info->irq, &tpm_tcg_bw, 107 ACPI_HANDLE(dev)); 108 } 109 110 static SIMPLE_DEV_PM_OPS(tpm_tis_synquacer_pm, tpm_pm_suspend, tpm_tis_resume); 111 112 static int tpm_tis_synquacer_probe(struct platform_device *pdev) 113 { 114 struct tpm_tis_synquacer_info tpm_info = {}; 115 struct resource *res; 116 117 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 118 if (res == NULL) { 119 dev_err(&pdev->dev, "no memory resource defined\n"); 120 return -ENODEV; 121 } 122 tpm_info.res = *res; 123 124 tpm_info.irq = -1; 125 126 return tpm_tis_synquacer_init(&pdev->dev, &tpm_info); 127 } 128 129 static void tpm_tis_synquacer_remove(struct platform_device *pdev) 130 { 131 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); 132 133 tpm_chip_unregister(chip); 134 tpm_tis_remove(chip); 135 } 136 137 #ifdef CONFIG_OF 138 static const struct of_device_id tis_synquacer_of_platform_match[] = { 139 {.compatible = "socionext,synquacer-tpm-mmio"}, 140 {}, 141 }; 142 MODULE_DEVICE_TABLE(of, tis_synquacer_of_platform_match); 143 #endif 144 145 #ifdef CONFIG_ACPI 146 static const struct acpi_device_id tpm_synquacer_acpi_tbl[] = { 147 { "SCX0009" }, 148 {}, 149 }; 150 MODULE_DEVICE_TABLE(acpi, tpm_synquacer_acpi_tbl); 151 #endif 152 153 static struct platform_driver tis_synquacer_drv = { 154 .probe = tpm_tis_synquacer_probe, 155 .remove_new = tpm_tis_synquacer_remove, 156 .driver = { 157 .name = "tpm_tis_synquacer", 158 .pm = &tpm_tis_synquacer_pm, 159 .of_match_table = of_match_ptr(tis_synquacer_of_platform_match), 160 .acpi_match_table = ACPI_PTR(tpm_synquacer_acpi_tbl), 161 }, 162 }; 163 164 module_platform_driver(tis_synquacer_drv); 165 166 MODULE_DESCRIPTION("TPM MMIO Driver for Socionext SynQuacer platform"); 167 MODULE_LICENSE("GPL"); 168