xref: /linux/drivers/net/phy/spi_ks8995.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /*
2  * SPI driver for Micrel/Kendin KS8995M ethernet switch
3  *
4  * Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org>
5  *
6  * This file was based on: drivers/spi/at25.c
7  *     Copyright (C) 2006 David Brownell
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published
11  * by the Free Software Foundation.
12  */
13 
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/delay.h>
19 #include <linux/device.h>
20 
21 #include <linux/spi/spi.h>
22 
23 #define DRV_VERSION		"0.1.1"
24 #define DRV_DESC		"Micrel KS8995 Ethernet switch SPI driver"
25 
26 /* ------------------------------------------------------------------------ */
27 
28 #define KS8995_REG_ID0		0x00    /* Chip ID0 */
29 #define KS8995_REG_ID1		0x01    /* Chip ID1 */
30 
31 #define KS8995_REG_GC0		0x02    /* Global Control 0 */
32 #define KS8995_REG_GC1		0x03    /* Global Control 1 */
33 #define KS8995_REG_GC2		0x04    /* Global Control 2 */
34 #define KS8995_REG_GC3		0x05    /* Global Control 3 */
35 #define KS8995_REG_GC4		0x06    /* Global Control 4 */
36 #define KS8995_REG_GC5		0x07    /* Global Control 5 */
37 #define KS8995_REG_GC6		0x08    /* Global Control 6 */
38 #define KS8995_REG_GC7		0x09    /* Global Control 7 */
39 #define KS8995_REG_GC8		0x0a    /* Global Control 8 */
40 #define KS8995_REG_GC9		0x0b    /* Global Control 9 */
41 
42 #define KS8995_REG_PC(p, r)	((0x10 * p) + r)	 /* Port Control */
43 #define KS8995_REG_PS(p, r)	((0x10 * p) + r + 0xe)  /* Port Status */
44 
45 #define KS8995_REG_TPC0		0x60    /* TOS Priority Control 0 */
46 #define KS8995_REG_TPC1		0x61    /* TOS Priority Control 1 */
47 #define KS8995_REG_TPC2		0x62    /* TOS Priority Control 2 */
48 #define KS8995_REG_TPC3		0x63    /* TOS Priority Control 3 */
49 #define KS8995_REG_TPC4		0x64    /* TOS Priority Control 4 */
50 #define KS8995_REG_TPC5		0x65    /* TOS Priority Control 5 */
51 #define KS8995_REG_TPC6		0x66    /* TOS Priority Control 6 */
52 #define KS8995_REG_TPC7		0x67    /* TOS Priority Control 7 */
53 
54 #define KS8995_REG_MAC0		0x68    /* MAC address 0 */
55 #define KS8995_REG_MAC1		0x69    /* MAC address 1 */
56 #define KS8995_REG_MAC2		0x6a    /* MAC address 2 */
57 #define KS8995_REG_MAC3		0x6b    /* MAC address 3 */
58 #define KS8995_REG_MAC4		0x6c    /* MAC address 4 */
59 #define KS8995_REG_MAC5		0x6d    /* MAC address 5 */
60 
61 #define KS8995_REG_IAC0		0x6e    /* Indirect Access Control 0 */
62 #define KS8995_REG_IAC1		0x6f    /* Indirect Access Control 0 */
63 #define KS8995_REG_IAD7		0x70    /* Indirect Access Data 7 */
64 #define KS8995_REG_IAD6		0x71    /* Indirect Access Data 6 */
65 #define KS8995_REG_IAD5		0x72    /* Indirect Access Data 5 */
66 #define KS8995_REG_IAD4		0x73    /* Indirect Access Data 4 */
67 #define KS8995_REG_IAD3		0x74    /* Indirect Access Data 3 */
68 #define KS8995_REG_IAD2		0x75    /* Indirect Access Data 2 */
69 #define KS8995_REG_IAD1		0x76    /* Indirect Access Data 1 */
70 #define KS8995_REG_IAD0		0x77    /* Indirect Access Data 0 */
71 
72 #define KS8995_REGS_SIZE	0x80
73 
74 #define ID1_CHIPID_M		0xf
75 #define ID1_CHIPID_S		4
76 #define ID1_REVISION_M		0x7
77 #define ID1_REVISION_S		1
78 #define ID1_START_SW		1	/* start the switch */
79 
80 #define FAMILY_KS8995		0x95
81 #define CHIPID_M		0
82 
83 #define KS8995_CMD_WRITE	0x02U
84 #define KS8995_CMD_READ		0x03U
85 
86 #define KS8995_RESET_DELAY	10 /* usec */
87 
88 struct ks8995_pdata {
89 	/* not yet implemented */
90 };
91 
92 struct ks8995_switch {
93 	struct spi_device	*spi;
94 	struct mutex		lock;
95 	struct ks8995_pdata	*pdata;
96 };
97 
98 static inline u8 get_chip_id(u8 val)
99 {
100 	return (val >> ID1_CHIPID_S) & ID1_CHIPID_M;
101 }
102 
103 static inline u8 get_chip_rev(u8 val)
104 {
105 	return (val >> ID1_REVISION_S) & ID1_REVISION_M;
106 }
107 
108 /* ------------------------------------------------------------------------ */
109 static int ks8995_read(struct ks8995_switch *ks, char *buf,
110 		 unsigned offset, size_t count)
111 {
112 	u8 cmd[2];
113 	struct spi_transfer t[2];
114 	struct spi_message m;
115 	int err;
116 
117 	spi_message_init(&m);
118 
119 	memset(&t, 0, sizeof(t));
120 
121 	t[0].tx_buf = cmd;
122 	t[0].len = sizeof(cmd);
123 	spi_message_add_tail(&t[0], &m);
124 
125 	t[1].rx_buf = buf;
126 	t[1].len = count;
127 	spi_message_add_tail(&t[1], &m);
128 
129 	cmd[0] = KS8995_CMD_READ;
130 	cmd[1] = offset;
131 
132 	mutex_lock(&ks->lock);
133 	err = spi_sync(ks->spi, &m);
134 	mutex_unlock(&ks->lock);
135 
136 	return err ? err : count;
137 }
138 
139 
140 static int ks8995_write(struct ks8995_switch *ks, char *buf,
141 		 unsigned offset, size_t count)
142 {
143 	u8 cmd[2];
144 	struct spi_transfer t[2];
145 	struct spi_message m;
146 	int err;
147 
148 	spi_message_init(&m);
149 
150 	memset(&t, 0, sizeof(t));
151 
152 	t[0].tx_buf = cmd;
153 	t[0].len = sizeof(cmd);
154 	spi_message_add_tail(&t[0], &m);
155 
156 	t[1].tx_buf = buf;
157 	t[1].len = count;
158 	spi_message_add_tail(&t[1], &m);
159 
160 	cmd[0] = KS8995_CMD_WRITE;
161 	cmd[1] = offset;
162 
163 	mutex_lock(&ks->lock);
164 	err = spi_sync(ks->spi, &m);
165 	mutex_unlock(&ks->lock);
166 
167 	return err ? err : count;
168 }
169 
170 static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf)
171 {
172 	return (ks8995_read(ks, buf, addr, 1) != 1);
173 }
174 
175 static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val)
176 {
177 	char buf = val;
178 
179 	return (ks8995_write(ks, &buf, addr, 1) != 1);
180 }
181 
182 /* ------------------------------------------------------------------------ */
183 
184 static int ks8995_stop(struct ks8995_switch *ks)
185 {
186 	return ks8995_write_reg(ks, KS8995_REG_ID1, 0);
187 }
188 
189 static int ks8995_start(struct ks8995_switch *ks)
190 {
191 	return ks8995_write_reg(ks, KS8995_REG_ID1, 1);
192 }
193 
194 static int ks8995_reset(struct ks8995_switch *ks)
195 {
196 	int err;
197 
198 	err = ks8995_stop(ks);
199 	if (err)
200 		return err;
201 
202 	udelay(KS8995_RESET_DELAY);
203 
204 	return ks8995_start(ks);
205 }
206 
207 /* ------------------------------------------------------------------------ */
208 
209 static ssize_t ks8995_registers_read(struct file *filp, struct kobject *kobj,
210 	struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
211 {
212 	struct device *dev;
213 	struct ks8995_switch *ks8995;
214 
215 	dev = container_of(kobj, struct device, kobj);
216 	ks8995 = dev_get_drvdata(dev);
217 
218 	if (unlikely(off > KS8995_REGS_SIZE))
219 		return 0;
220 
221 	if ((off + count) > KS8995_REGS_SIZE)
222 		count = KS8995_REGS_SIZE - off;
223 
224 	if (unlikely(!count))
225 		return count;
226 
227 	return ks8995_read(ks8995, buf, off, count);
228 }
229 
230 
231 static ssize_t ks8995_registers_write(struct file *filp, struct kobject *kobj,
232 	struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
233 {
234 	struct device *dev;
235 	struct ks8995_switch *ks8995;
236 
237 	dev = container_of(kobj, struct device, kobj);
238 	ks8995 = dev_get_drvdata(dev);
239 
240 	if (unlikely(off >= KS8995_REGS_SIZE))
241 		return -EFBIG;
242 
243 	if ((off + count) > KS8995_REGS_SIZE)
244 		count = KS8995_REGS_SIZE - off;
245 
246 	if (unlikely(!count))
247 		return count;
248 
249 	return ks8995_write(ks8995, buf, off, count);
250 }
251 
252 
253 static struct bin_attribute ks8995_registers_attr = {
254 	.attr = {
255 		.name   = "registers",
256 		.mode   = S_IRUSR | S_IWUSR,
257 	},
258 	.size   = KS8995_REGS_SIZE,
259 	.read   = ks8995_registers_read,
260 	.write  = ks8995_registers_write,
261 };
262 
263 /* ------------------------------------------------------------------------ */
264 
265 static int __devinit ks8995_probe(struct spi_device *spi)
266 {
267 	struct ks8995_switch    *ks;
268 	struct ks8995_pdata     *pdata;
269 	u8      ids[2];
270 	int     err;
271 
272 	/* Chip description */
273 	pdata = spi->dev.platform_data;
274 
275 	ks = kzalloc(sizeof(*ks), GFP_KERNEL);
276 	if (!ks) {
277 		dev_err(&spi->dev, "no memory for private data\n");
278 		return -ENOMEM;
279 	}
280 
281 	mutex_init(&ks->lock);
282 	ks->pdata = pdata;
283 	ks->spi = spi_dev_get(spi);
284 	dev_set_drvdata(&spi->dev, ks);
285 
286 	spi->mode = SPI_MODE_0;
287 	spi->bits_per_word = 8;
288 	err = spi_setup(spi);
289 	if (err) {
290 		dev_err(&spi->dev, "spi_setup failed, err=%d\n", err);
291 		goto err_drvdata;
292 	}
293 
294 	err = ks8995_read(ks, ids, KS8995_REG_ID0, sizeof(ids));
295 	if (err < 0) {
296 		dev_err(&spi->dev, "unable to read id registers, err=%d\n",
297 				err);
298 		goto err_drvdata;
299 	}
300 
301 	switch (ids[0]) {
302 	case FAMILY_KS8995:
303 		break;
304 	default:
305 		dev_err(&spi->dev, "unknown family id:%02x\n", ids[0]);
306 		err = -ENODEV;
307 		goto err_drvdata;
308 	}
309 
310 	err = ks8995_reset(ks);
311 	if (err)
312 		goto err_drvdata;
313 
314 	err = sysfs_create_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
315 	if (err) {
316 		dev_err(&spi->dev, "unable to create sysfs file, err=%d\n",
317 				    err);
318 		goto err_drvdata;
319 	}
320 
321 	dev_info(&spi->dev, "KS89%02X device found, Chip ID:%01x, "
322 			"Revision:%01x\n", ids[0],
323 			get_chip_id(ids[1]), get_chip_rev(ids[1]));
324 
325 	return 0;
326 
327 err_drvdata:
328 	dev_set_drvdata(&spi->dev, NULL);
329 	kfree(ks);
330 	return err;
331 }
332 
333 static int __devexit ks8995_remove(struct spi_device *spi)
334 {
335 	struct ks8995_data      *ks8995;
336 
337 	ks8995 = dev_get_drvdata(&spi->dev);
338 	sysfs_remove_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
339 
340 	dev_set_drvdata(&spi->dev, NULL);
341 	kfree(ks8995);
342 
343 	return 0;
344 }
345 
346 /* ------------------------------------------------------------------------ */
347 
348 static struct spi_driver ks8995_driver = {
349 	.driver = {
350 		.name	    = "spi-ks8995",
351 		.owner	   = THIS_MODULE,
352 	},
353 	.probe	  = ks8995_probe,
354 	.remove	  = __devexit_p(ks8995_remove),
355 };
356 
357 static int __init ks8995_init(void)
358 {
359 	printk(KERN_INFO DRV_DESC " version " DRV_VERSION"\n");
360 
361 	return spi_register_driver(&ks8995_driver);
362 }
363 module_init(ks8995_init);
364 
365 static void __exit ks8995_exit(void)
366 {
367 	spi_unregister_driver(&ks8995_driver);
368 }
369 module_exit(ks8995_exit);
370 
371 MODULE_DESCRIPTION(DRV_DESC);
372 MODULE_VERSION(DRV_VERSION);
373 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
374 MODULE_LICENSE("GPL v2");
375