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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 | // SPDX-License-Identifier: GPL-2.0-only /* * Driver for the Diolan DLN-2 USB-I2C adapter * * Copyright (c) 2014 Intel Corporation * * Derived from: * i2c-diolan-u2c.c * Copyright (c) 2010-2011 Ericsson AB */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/types.h> #include <linux/slab.h> #include <linux/i2c.h> #include <linux/platform_device.h> #include <linux/mfd/dln2.h> #include <linux/acpi.h> #define DLN2_I2C_MODULE_ID 0x03 #define DLN2_I2C_CMD(cmd) DLN2_CMD(cmd, DLN2_I2C_MODULE_ID) /* I2C commands */ #define DLN2_I2C_GET_PORT_COUNT DLN2_I2C_CMD(0x00) #define DLN2_I2C_ENABLE DLN2_I2C_CMD(0x01) #define DLN2_I2C_DISABLE DLN2_I2C_CMD(0x02) #define DLN2_I2C_IS_ENABLED DLN2_I2C_CMD(0x03) #define DLN2_I2C_WRITE DLN2_I2C_CMD(0x06) #define DLN2_I2C_READ DLN2_I2C_CMD(0x07) #define DLN2_I2C_SCAN_DEVICES DLN2_I2C_CMD(0x08) #define DLN2_I2C_PULLUP_ENABLE DLN2_I2C_CMD(0x09) #define DLN2_I2C_PULLUP_DISABLE DLN2_I2C_CMD(0x0A) #define DLN2_I2C_PULLUP_IS_ENABLED DLN2_I2C_CMD(0x0B) #define DLN2_I2C_TRANSFER DLN2_I2C_CMD(0x0C) #define DLN2_I2C_SET_MAX_REPLY_COUNT DLN2_I2C_CMD(0x0D) #define DLN2_I2C_GET_MAX_REPLY_COUNT DLN2_I2C_CMD(0x0E) #define DLN2_I2C_MAX_XFER_SIZE 256 #define DLN2_I2C_BUF_SIZE (DLN2_I2C_MAX_XFER_SIZE + 16) struct dln2_i2c { struct platform_device *pdev; struct i2c_adapter adapter; u8 port; /* * Buffer to hold the packet for read or write transfers. One is enough * since we can't have multiple transfers in parallel on the i2c bus. */ void *buf; }; static int dln2_i2c_enable(struct dln2_i2c *dln2, bool enable) { u16 cmd; struct { u8 port; } tx; tx.port = dln2->port; if (enable) cmd = DLN2_I2C_ENABLE; else cmd = DLN2_I2C_DISABLE; return dln2_transfer_tx(dln2->pdev, cmd, &tx, sizeof(tx)); } static int dln2_i2c_write(struct dln2_i2c *dln2, u8 addr, u8 *data, u16 data_len) { int ret; struct { u8 port; u8 addr; u8 mem_addr_len; __le32 mem_addr; __le16 buf_len; u8 buf[DLN2_I2C_MAX_XFER_SIZE]; } __packed *tx = dln2->buf; unsigned len; BUILD_BUG_ON(sizeof(*tx) > DLN2_I2C_BUF_SIZE); tx->port = dln2->port; tx->addr = addr; tx->mem_addr_len = 0; tx->mem_addr = 0; tx->buf_len = cpu_to_le16(data_len); memcpy(tx->buf, data, data_len); len = sizeof(*tx) + data_len - DLN2_I2C_MAX_XFER_SIZE; ret = dln2_transfer_tx(dln2->pdev, DLN2_I2C_WRITE, tx, len); if (ret < 0) return ret; return data_len; } static int dln2_i2c_read(struct dln2_i2c *dln2, u16 addr, u8 *data, u16 data_len) { int ret; struct { u8 port; u8 addr; u8 mem_addr_len; __le32 mem_addr; __le16 buf_len; } __packed tx; struct { __le16 buf_len; u8 buf[DLN2_I2C_MAX_XFER_SIZE]; } __packed *rx = dln2->buf; unsigned rx_len = sizeof(*rx); BUILD_BUG_ON(sizeof(*rx) > DLN2_I2C_BUF_SIZE); tx.port = dln2->port; tx.addr = addr; tx.mem_addr_len = 0; tx.mem_addr = 0; tx.buf_len = cpu_to_le16(data_len); ret = dln2_transfer(dln2->pdev, DLN2_I2C_READ, &tx, sizeof(tx), rx, &rx_len); if (ret < 0) return ret; if (rx_len < sizeof(rx->buf_len) + data_len) return -EPROTO; if (le16_to_cpu(rx->buf_len) != data_len) return -EPROTO; memcpy(data, rx->buf, data_len); return data_len; } static int dln2_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { struct dln2_i2c *dln2 = i2c_get_adapdata(adapter); struct i2c_msg *pmsg; int i; for (i = 0; i < num; i++) { int ret; pmsg = &msgs[i]; if (pmsg->flags & I2C_M_RD) { ret = dln2_i2c_read(dln2, pmsg->addr, pmsg->buf, pmsg->len); if (ret < 0) return ret; pmsg->len = ret; } else { ret = dln2_i2c_write(dln2, pmsg->addr, pmsg->buf, pmsg->len); if (ret != pmsg->len) return -EPROTO; } } return num; } static u32 dln2_i2c_func(struct i2c_adapter *a) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL | I2C_FUNC_SMBUS_I2C_BLOCK; } static const struct i2c_algorithm dln2_i2c_usb_algorithm = { .master_xfer = dln2_i2c_xfer, .functionality = dln2_i2c_func, }; static const struct i2c_adapter_quirks dln2_i2c_quirks = { .max_read_len = DLN2_I2C_MAX_XFER_SIZE, .max_write_len = DLN2_I2C_MAX_XFER_SIZE, }; static int dln2_i2c_probe(struct platform_device *pdev) { int ret; struct dln2_i2c *dln2; struct device *dev = &pdev->dev; struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev); dln2 = devm_kzalloc(dev, sizeof(*dln2), GFP_KERNEL); if (!dln2) return -ENOMEM; dln2->buf = devm_kmalloc(dev, DLN2_I2C_BUF_SIZE, GFP_KERNEL); if (!dln2->buf) return -ENOMEM; dln2->pdev = pdev; dln2->port = pdata->port; /* setup i2c adapter description */ dln2->adapter.owner = THIS_MODULE; dln2->adapter.class = I2C_CLASS_HWMON; dln2->adapter.algo = &dln2_i2c_usb_algorithm; dln2->adapter.quirks = &dln2_i2c_quirks; dln2->adapter.dev.parent = dev; ACPI_COMPANION_SET(&dln2->adapter.dev, ACPI_COMPANION(&pdev->dev)); dln2->adapter.dev.of_node = dev->of_node; i2c_set_adapdata(&dln2->adapter, dln2); snprintf(dln2->adapter.name, sizeof(dln2->adapter.name), "%s-%s-%d", "dln2-i2c", dev_name(pdev->dev.parent), dln2->port); platform_set_drvdata(pdev, dln2); /* initialize the i2c interface */ ret = dln2_i2c_enable(dln2, true); if (ret < 0) { dev_err(dev, "failed to initialize adapter: %d\n", ret); return ret; } /* and finally attach to i2c layer */ ret = i2c_add_adapter(&dln2->adapter); if (ret < 0) goto out_disable; return 0; out_disable: dln2_i2c_enable(dln2, false); return ret; } static int dln2_i2c_remove(struct platform_device *pdev) { struct dln2_i2c *dln2 = platform_get_drvdata(pdev); i2c_del_adapter(&dln2->adapter); dln2_i2c_enable(dln2, false); return 0; } static struct platform_driver dln2_i2c_driver = { .driver.name = "dln2-i2c", .probe = dln2_i2c_probe, .remove = dln2_i2c_remove, }; module_platform_driver(dln2_i2c_driver); MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>"); MODULE_DESCRIPTION("Driver for the Diolan DLN2 I2C master interface"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:dln2-i2c"); |