2 * Driver for the Diolan DLN-2 USB-I2C adapter
4 * Copyright (c) 2014 Intel Corporation
8 * Copyright (c) 2010-2011 Ericsson AB
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation, version 2.
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/slab.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_device.h>
21 #include <linux/mfd/dln2.h>
23 #define DLN2_I2C_MODULE_ID 0x03
24 #define DLN2_I2C_CMD(cmd) DLN2_CMD(cmd, DLN2_I2C_MODULE_ID)
27 #define DLN2_I2C_GET_PORT_COUNT DLN2_I2C_CMD(0x00)
28 #define DLN2_I2C_ENABLE DLN2_I2C_CMD(0x01)
29 #define DLN2_I2C_DISABLE DLN2_I2C_CMD(0x02)
30 #define DLN2_I2C_IS_ENABLED DLN2_I2C_CMD(0x03)
31 #define DLN2_I2C_WRITE DLN2_I2C_CMD(0x06)
32 #define DLN2_I2C_READ DLN2_I2C_CMD(0x07)
33 #define DLN2_I2C_SCAN_DEVICES DLN2_I2C_CMD(0x08)
34 #define DLN2_I2C_PULLUP_ENABLE DLN2_I2C_CMD(0x09)
35 #define DLN2_I2C_PULLUP_DISABLE DLN2_I2C_CMD(0x0A)
36 #define DLN2_I2C_PULLUP_IS_ENABLED DLN2_I2C_CMD(0x0B)
37 #define DLN2_I2C_TRANSFER DLN2_I2C_CMD(0x0C)
38 #define DLN2_I2C_SET_MAX_REPLY_COUNT DLN2_I2C_CMD(0x0D)
39 #define DLN2_I2C_GET_MAX_REPLY_COUNT DLN2_I2C_CMD(0x0E)
41 #define DLN2_I2C_MAX_XFER_SIZE 256
42 #define DLN2_I2C_BUF_SIZE (DLN2_I2C_MAX_XFER_SIZE + 16)
45 struct platform_device *pdev;
46 struct i2c_adapter adapter;
49 * Buffer to hold the packet for read or write transfers. One is enough
50 * since we can't have multiple transfers in parallel on the i2c bus.
55 static int dln2_i2c_enable(struct dln2_i2c *dln2, bool enable)
65 cmd = DLN2_I2C_ENABLE;
67 cmd = DLN2_I2C_DISABLE;
69 return dln2_transfer_tx(dln2->pdev, cmd, &tx, sizeof(tx));
72 static int dln2_i2c_write(struct dln2_i2c *dln2, u8 addr,
73 u8 *data, u16 data_len)
82 u8 buf[DLN2_I2C_MAX_XFER_SIZE];
83 } __packed *tx = dln2->buf;
86 BUILD_BUG_ON(sizeof(*tx) > DLN2_I2C_BUF_SIZE);
88 tx->port = dln2->port;
92 tx->buf_len = cpu_to_le16(data_len);
93 memcpy(tx->buf, data, data_len);
95 len = sizeof(*tx) + data_len - DLN2_I2C_MAX_XFER_SIZE;
96 ret = dln2_transfer_tx(dln2->pdev, DLN2_I2C_WRITE, tx, len);
103 static int dln2_i2c_read(struct dln2_i2c *dln2, u16 addr, u8 *data,
116 u8 buf[DLN2_I2C_MAX_XFER_SIZE];
117 } __packed *rx = dln2->buf;
118 unsigned rx_len = sizeof(*rx);
120 BUILD_BUG_ON(sizeof(*rx) > DLN2_I2C_BUF_SIZE);
122 tx.port = dln2->port;
126 tx.buf_len = cpu_to_le16(data_len);
128 ret = dln2_transfer(dln2->pdev, DLN2_I2C_READ, &tx, sizeof(tx),
132 if (rx_len < sizeof(rx->buf_len) + data_len)
134 if (le16_to_cpu(rx->buf_len) != data_len)
137 memcpy(data, rx->buf, data_len);
142 static int dln2_i2c_xfer(struct i2c_adapter *adapter,
143 struct i2c_msg *msgs, int num)
145 struct dln2_i2c *dln2 = i2c_get_adapdata(adapter);
146 struct i2c_msg *pmsg;
149 for (i = 0; i < num; i++) {
154 if (pmsg->flags & I2C_M_RD) {
155 ret = dln2_i2c_read(dln2, pmsg->addr, pmsg->buf,
162 ret = dln2_i2c_write(dln2, pmsg->addr, pmsg->buf,
164 if (ret != pmsg->len)
172 static u32 dln2_i2c_func(struct i2c_adapter *a)
174 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA |
175 I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
176 I2C_FUNC_SMBUS_I2C_BLOCK;
179 static const struct i2c_algorithm dln2_i2c_usb_algorithm = {
180 .master_xfer = dln2_i2c_xfer,
181 .functionality = dln2_i2c_func,
184 static struct i2c_adapter_quirks dln2_i2c_quirks = {
185 .max_read_len = DLN2_I2C_MAX_XFER_SIZE,
186 .max_write_len = DLN2_I2C_MAX_XFER_SIZE,
189 static int dln2_i2c_probe(struct platform_device *pdev)
192 struct dln2_i2c *dln2;
193 struct device *dev = &pdev->dev;
194 struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev);
196 dln2 = devm_kzalloc(dev, sizeof(*dln2), GFP_KERNEL);
200 dln2->buf = devm_kmalloc(dev, DLN2_I2C_BUF_SIZE, GFP_KERNEL);
205 dln2->port = pdata->port;
207 /* setup i2c adapter description */
208 dln2->adapter.owner = THIS_MODULE;
209 dln2->adapter.class = I2C_CLASS_HWMON;
210 dln2->adapter.algo = &dln2_i2c_usb_algorithm;
211 dln2->adapter.quirks = &dln2_i2c_quirks;
212 dln2->adapter.dev.parent = dev;
213 dln2->adapter.dev.of_node = dev->of_node;
214 i2c_set_adapdata(&dln2->adapter, dln2);
215 snprintf(dln2->adapter.name, sizeof(dln2->adapter.name), "%s-%s-%d",
216 "dln2-i2c", dev_name(pdev->dev.parent), dln2->port);
218 platform_set_drvdata(pdev, dln2);
220 /* initialize the i2c interface */
221 ret = dln2_i2c_enable(dln2, true);
223 dev_err(dev, "failed to initialize adapter: %d\n", ret);
227 /* and finally attach to i2c layer */
228 ret = i2c_add_adapter(&dln2->adapter);
230 dev_err(dev, "failed to add I2C adapter: %d\n", ret);
237 dln2_i2c_enable(dln2, false);
242 static int dln2_i2c_remove(struct platform_device *pdev)
244 struct dln2_i2c *dln2 = platform_get_drvdata(pdev);
246 i2c_del_adapter(&dln2->adapter);
247 dln2_i2c_enable(dln2, false);
252 static struct platform_driver dln2_i2c_driver = {
253 .driver.name = "dln2-i2c",
254 .probe = dln2_i2c_probe,
255 .remove = dln2_i2c_remove,
258 module_platform_driver(dln2_i2c_driver);
260 MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>");
261 MODULE_DESCRIPTION("Driver for the Diolan DLN2 I2C master interface");
262 MODULE_LICENSE("GPL v2");
263 MODULE_ALIAS("platform:dln2-i2c");