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83d290c5 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
5e862b95 AA |
2 | /* |
3 | * LPC32xx I2C interface driver | |
4 | * | |
1933af15 | 5 | * (C) Copyright 2014-2015 DENX Software Engineering GmbH |
5e862b95 | 6 | * Written-by: Albert ARIBAUD - 3ADEV <[email protected]> |
5e862b95 AA |
7 | */ |
8 | ||
9 | #include <common.h> | |
f7ae49fc | 10 | #include <log.h> |
5e862b95 AA |
11 | #include <asm/io.h> |
12 | #include <i2c.h> | |
1221ce45 | 13 | #include <linux/errno.h> |
5e862b95 | 14 | #include <asm/arch/clk.h> |
fb057880 | 15 | #include <asm/arch/i2c.h> |
d61c7adb LB |
16 | #include <dm.h> |
17 | #include <mapmem.h> | |
5e862b95 AA |
18 | |
19 | /* | |
20 | * Provide default speed and slave if target did not | |
21 | */ | |
22 | ||
23 | #if !defined(CONFIG_SYS_I2C_LPC32XX_SPEED) | |
24 | #define CONFIG_SYS_I2C_LPC32XX_SPEED 350000 | |
25 | #endif | |
26 | ||
27 | #if !defined(CONFIG_SYS_I2C_LPC32XX_SLAVE) | |
28 | #define CONFIG_SYS_I2C_LPC32XX_SLAVE 0 | |
29 | #endif | |
30 | ||
5e862b95 AA |
31 | /* TX register fields */ |
32 | #define LPC32XX_I2C_TX_START 0x00000100 | |
33 | #define LPC32XX_I2C_TX_STOP 0x00000200 | |
34 | ||
35 | /* Control register values */ | |
36 | #define LPC32XX_I2C_SOFT_RESET 0x00000100 | |
37 | ||
38 | /* Status register values */ | |
39 | #define LPC32XX_I2C_STAT_TFF 0x00000400 | |
40 | #define LPC32XX_I2C_STAT_RFE 0x00000200 | |
41 | #define LPC32XX_I2C_STAT_DRMI 0x00000008 | |
42 | #define LPC32XX_I2C_STAT_NAI 0x00000004 | |
43 | #define LPC32XX_I2C_STAT_TDI 0x00000001 | |
44 | ||
d61c7adb | 45 | #ifndef CONFIG_DM_I2C |
eddac8e9 LB |
46 | static struct lpc32xx_i2c_base *lpc32xx_i2c[] = { |
47 | (struct lpc32xx_i2c_base *)I2C1_BASE, | |
48 | (struct lpc32xx_i2c_base *)I2C2_BASE, | |
49 | (struct lpc32xx_i2c_base *)(USB_BASE + 0x300) | |
5e862b95 | 50 | }; |
d61c7adb | 51 | #endif |
5e862b95 AA |
52 | |
53 | /* Set I2C bus speed */ | |
eddac8e9 LB |
54 | static unsigned int __i2c_set_bus_speed(struct lpc32xx_i2c_base *base, |
55 | unsigned int speed, unsigned int chip) | |
5e862b95 AA |
56 | { |
57 | int half_period; | |
58 | ||
59 | if (speed == 0) | |
60 | return -EINVAL; | |
61 | ||
ea16c6a1 | 62 | /* OTG I2C clock source and CLK registers are different */ |
eddac8e9 | 63 | if (chip == 2) { |
ea16c6a1 VZ |
64 | half_period = (get_periph_clk_rate() / speed) / 2; |
65 | if (half_period > 0xFF) | |
66 | return -EINVAL; | |
67 | } else { | |
68 | half_period = (get_hclk_clk_rate() / speed) / 2; | |
69 | if (half_period > 0x3FF) | |
70 | return -EINVAL; | |
71 | } | |
5e862b95 | 72 | |
eddac8e9 LB |
73 | writel(half_period, &base->clk_hi); |
74 | writel(half_period, &base->clk_lo); | |
5e862b95 AA |
75 | return 0; |
76 | } | |
77 | ||
78 | /* I2C init called by cmd_i2c when doing 'i2c reset'. */ | |
eddac8e9 LB |
79 | static void __i2c_init(struct lpc32xx_i2c_base *base, |
80 | int requested_speed, int slaveadd, unsigned int chip) | |
5e862b95 | 81 | { |
5e862b95 | 82 | /* soft reset (auto-clears) */ |
eddac8e9 | 83 | writel(LPC32XX_I2C_SOFT_RESET, &base->ctrl); |
ea16c6a1 | 84 | /* set HI and LO periods for half of the default speed */ |
eddac8e9 | 85 | __i2c_set_bus_speed(base, requested_speed, chip); |
5e862b95 AA |
86 | } |
87 | ||
88 | /* I2C probe called by cmd_i2c when doing 'i2c probe'. */ | |
eddac8e9 | 89 | static int __i2c_probe_chip(struct lpc32xx_i2c_base *base, u8 dev) |
5e862b95 | 90 | { |
5e862b95 AA |
91 | int stat; |
92 | ||
93 | /* Soft-reset the controller */ | |
eddac8e9 LB |
94 | writel(LPC32XX_I2C_SOFT_RESET, &base->ctrl); |
95 | while (readl(&base->ctrl) & LPC32XX_I2C_SOFT_RESET) | |
5e862b95 AA |
96 | ; |
97 | /* Addre slave for write with start before and stop after */ | |
98 | writel((dev<<1) | LPC32XX_I2C_TX_START | LPC32XX_I2C_TX_STOP, | |
eddac8e9 | 99 | &base->tx); |
5e862b95 | 100 | /* wait for end of transation */ |
eddac8e9 | 101 | while (!((stat = readl(&base->stat)) & LPC32XX_I2C_STAT_TDI)) |
5e862b95 AA |
102 | ; |
103 | /* was there no acknowledge? */ | |
104 | return (stat & LPC32XX_I2C_STAT_NAI) ? -1 : 0; | |
105 | } | |
106 | ||
107 | /* | |
108 | * I2C read called by cmd_i2c when doing 'i2c read' and by cmd_eeprom.c | |
109 | * Begin write, send address byte(s), begin read, receive data bytes, end. | |
110 | */ | |
eddac8e9 LB |
111 | static int __i2c_read(struct lpc32xx_i2c_base *base, u8 dev, uint addr, |
112 | int alen, u8 *data, int length) | |
5e862b95 | 113 | { |
5e862b95 AA |
114 | int stat, wlen; |
115 | ||
116 | /* Soft-reset the controller */ | |
eddac8e9 LB |
117 | writel(LPC32XX_I2C_SOFT_RESET, &base->ctrl); |
118 | while (readl(&base->ctrl) & LPC32XX_I2C_SOFT_RESET) | |
5e862b95 AA |
119 | ; |
120 | /* do we need to write an address at all? */ | |
121 | if (alen) { | |
122 | /* Address slave in write mode */ | |
eddac8e9 | 123 | writel((dev<<1) | LPC32XX_I2C_TX_START, &base->tx); |
5e862b95 AA |
124 | /* write address bytes */ |
125 | while (alen--) { | |
126 | /* compute address byte + stop for the last one */ | |
127 | int a = (addr >> (8 * alen)) & 0xff; | |
128 | if (!alen) | |
129 | a |= LPC32XX_I2C_TX_STOP; | |
130 | /* Send address byte */ | |
eddac8e9 | 131 | writel(a, &base->tx); |
5e862b95 AA |
132 | } |
133 | /* wait for end of transation */ | |
eddac8e9 | 134 | while (!((stat = readl(&base->stat)) & LPC32XX_I2C_STAT_TDI)) |
5e862b95 AA |
135 | ; |
136 | /* clear end-of-transaction flag */ | |
eddac8e9 | 137 | writel(1, &base->stat); |
5e862b95 AA |
138 | } |
139 | /* do we have to read data at all? */ | |
140 | if (length) { | |
141 | /* Address slave in read mode */ | |
eddac8e9 | 142 | writel(1 | (dev<<1) | LPC32XX_I2C_TX_START, &base->tx); |
5e862b95 AA |
143 | wlen = length; |
144 | /* get data */ | |
145 | while (length | wlen) { | |
146 | /* read status for TFF and RFE */ | |
eddac8e9 | 147 | stat = readl(&base->stat); |
5e862b95 AA |
148 | /* must we, can we write a trigger byte? */ |
149 | if ((wlen > 0) | |
150 | & (!(stat & LPC32XX_I2C_STAT_TFF))) { | |
151 | wlen--; | |
152 | /* write trigger byte + stop if last */ | |
153 | writel(wlen ? 0 : | |
eddac8e9 | 154 | LPC32XX_I2C_TX_STOP, &base->tx); |
5e862b95 AA |
155 | } |
156 | /* must we, can we read a data byte? */ | |
157 | if ((length > 0) | |
158 | & (!(stat & LPC32XX_I2C_STAT_RFE))) { | |
159 | length--; | |
160 | /* read byte */ | |
eddac8e9 | 161 | *(data++) = readl(&base->rx); |
5e862b95 AA |
162 | } |
163 | } | |
3d2b6a2e | 164 | /* wait for end of transation */ |
eddac8e9 | 165 | while (!((stat = readl(&base->stat)) & LPC32XX_I2C_STAT_TDI)) |
3d2b6a2e SL |
166 | ; |
167 | /* clear end-of-transaction flag */ | |
eddac8e9 | 168 | writel(1, &base->stat); |
5e862b95 | 169 | } |
5e862b95 AA |
170 | /* success */ |
171 | return 0; | |
172 | } | |
173 | ||
174 | /* | |
175 | * I2C write called by cmd_i2c when doing 'i2c write' and by cmd_eeprom.c | |
176 | * Begin write, send address byte(s), send data bytes, end. | |
177 | */ | |
eddac8e9 LB |
178 | static int __i2c_write(struct lpc32xx_i2c_base *base, u8 dev, uint addr, |
179 | int alen, u8 *data, int length) | |
5e862b95 | 180 | { |
5e862b95 AA |
181 | int stat; |
182 | ||
183 | /* Soft-reset the controller */ | |
eddac8e9 LB |
184 | writel(LPC32XX_I2C_SOFT_RESET, &base->ctrl); |
185 | while (readl(&base->ctrl) & LPC32XX_I2C_SOFT_RESET) | |
5e862b95 AA |
186 | ; |
187 | /* do we need to write anything at all? */ | |
188 | if (alen | length) | |
189 | /* Address slave in write mode */ | |
eddac8e9 | 190 | writel((dev<<1) | LPC32XX_I2C_TX_START, &base->tx); |
58243001 SL |
191 | else |
192 | return 0; | |
5e862b95 AA |
193 | /* write address bytes */ |
194 | while (alen) { | |
195 | /* wait for transmit fifo not full */ | |
eddac8e9 | 196 | stat = readl(&base->stat); |
5e862b95 AA |
197 | if (!(stat & LPC32XX_I2C_STAT_TFF)) { |
198 | alen--; | |
199 | int a = (addr >> (8 * alen)) & 0xff; | |
200 | if (!(alen | length)) | |
201 | a |= LPC32XX_I2C_TX_STOP; | |
202 | /* Send address byte */ | |
eddac8e9 | 203 | writel(a, &base->tx); |
5e862b95 AA |
204 | } |
205 | } | |
206 | while (length) { | |
207 | /* wait for transmit fifo not full */ | |
eddac8e9 | 208 | stat = readl(&base->stat); |
5e862b95 AA |
209 | if (!(stat & LPC32XX_I2C_STAT_TFF)) { |
210 | /* compute data byte, add stop if length==0 */ | |
211 | length--; | |
212 | int d = *(data++); | |
213 | if (!length) | |
214 | d |= LPC32XX_I2C_TX_STOP; | |
215 | /* Send data byte */ | |
eddac8e9 | 216 | writel(d, &base->tx); |
5e862b95 AA |
217 | } |
218 | } | |
219 | /* wait for end of transation */ | |
eddac8e9 | 220 | while (!((stat = readl(&base->stat)) & LPC32XX_I2C_STAT_TDI)) |
5e862b95 AA |
221 | ; |
222 | /* clear end-of-transaction flag */ | |
eddac8e9 | 223 | writel(1, &base->stat); |
5e862b95 AA |
224 | return 0; |
225 | } | |
226 | ||
d61c7adb | 227 | #ifndef CONFIG_DM_I2C |
552531e4 LB |
228 | static void lpc32xx_i2c_init(struct i2c_adapter *adap, |
229 | int requested_speed, int slaveadd) | |
230 | { | |
eddac8e9 LB |
231 | __i2c_init(lpc32xx_i2c[adap->hwadapnr], requested_speed, slaveadd, |
232 | adap->hwadapnr); | |
552531e4 LB |
233 | } |
234 | ||
235 | static int lpc32xx_i2c_probe_chip(struct i2c_adapter *adap, u8 dev) | |
236 | { | |
eddac8e9 | 237 | return __i2c_probe_chip(lpc32xx_i2c[adap->hwadapnr], dev); |
552531e4 LB |
238 | } |
239 | ||
240 | static int lpc32xx_i2c_read(struct i2c_adapter *adap, u8 dev, uint addr, | |
241 | int alen, u8 *data, int length) | |
242 | { | |
eddac8e9 LB |
243 | return __i2c_read(lpc32xx_i2c[adap->hwadapnr], dev, addr, |
244 | alen, data, length); | |
552531e4 LB |
245 | } |
246 | ||
247 | static int lpc32xx_i2c_write(struct i2c_adapter *adap, u8 dev, uint addr, | |
248 | int alen, u8 *data, int length) | |
249 | { | |
eddac8e9 LB |
250 | return __i2c_write(lpc32xx_i2c[adap->hwadapnr], dev, addr, |
251 | alen, data, length); | |
552531e4 LB |
252 | } |
253 | ||
254 | static unsigned int lpc32xx_i2c_set_bus_speed(struct i2c_adapter *adap, | |
255 | unsigned int speed) | |
256 | { | |
eddac8e9 LB |
257 | return __i2c_set_bus_speed(lpc32xx_i2c[adap->hwadapnr], speed, |
258 | adap->hwadapnr); | |
552531e4 LB |
259 | } |
260 | ||
261 | U_BOOT_I2C_ADAP_COMPLETE(lpc32xx_0, lpc32xx_i2c_init, lpc32xx_i2c_probe_chip, | |
5e862b95 AA |
262 | lpc32xx_i2c_read, lpc32xx_i2c_write, |
263 | lpc32xx_i2c_set_bus_speed, | |
264 | CONFIG_SYS_I2C_LPC32XX_SPEED, | |
265 | CONFIG_SYS_I2C_LPC32XX_SLAVE, | |
266 | 0) | |
267 | ||
552531e4 | 268 | U_BOOT_I2C_ADAP_COMPLETE(lpc32xx_1, lpc32xx_i2c_init, lpc32xx_i2c_probe_chip, |
5e862b95 AA |
269 | lpc32xx_i2c_read, lpc32xx_i2c_write, |
270 | lpc32xx_i2c_set_bus_speed, | |
271 | CONFIG_SYS_I2C_LPC32XX_SPEED, | |
272 | CONFIG_SYS_I2C_LPC32XX_SLAVE, | |
273 | 1) | |
1933af15 | 274 | |
552531e4 | 275 | U_BOOT_I2C_ADAP_COMPLETE(lpc32xx_2, lpc32xx_i2c_init, NULL, |
1933af15 SL |
276 | lpc32xx_i2c_read, lpc32xx_i2c_write, |
277 | lpc32xx_i2c_set_bus_speed, | |
278 | 100000, | |
279 | 0, | |
280 | 2) | |
d61c7adb LB |
281 | #else /* CONFIG_DM_I2C */ |
282 | static int lpc32xx_i2c_probe(struct udevice *bus) | |
283 | { | |
284 | struct lpc32xx_i2c_dev *dev = dev_get_platdata(bus); | |
0f5b461b | 285 | bus->seq = dev->index; |
d61c7adb LB |
286 | |
287 | __i2c_init(dev->base, dev->speed, 0, dev->index); | |
288 | return 0; | |
289 | } | |
290 | ||
291 | static int lpc32xx_i2c_probe_chip(struct udevice *bus, u32 chip_addr, | |
292 | u32 chip_flags) | |
293 | { | |
294 | struct lpc32xx_i2c_dev *dev = dev_get_platdata(bus); | |
295 | return __i2c_probe_chip(dev->base, chip_addr); | |
296 | } | |
297 | ||
298 | static int lpc32xx_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, | |
299 | int nmsgs) | |
300 | { | |
301 | struct lpc32xx_i2c_dev *dev = dev_get_platdata(bus); | |
302 | struct i2c_msg *dmsg, *omsg, dummy; | |
303 | uint i = 0, address = 0; | |
304 | ||
305 | memset(&dummy, 0, sizeof(struct i2c_msg)); | |
306 | ||
307 | /* We expect either two messages (one with an offset and one with the | |
308 | * actual data) or one message (just data) | |
309 | */ | |
310 | if (nmsgs > 2 || nmsgs == 0) { | |
311 | debug("%s: Only one or two messages are supported.", __func__); | |
312 | return -1; | |
313 | } | |
314 | ||
315 | omsg = nmsgs == 1 ? &dummy : msg; | |
316 | dmsg = nmsgs == 1 ? msg : msg + 1; | |
317 | ||
318 | /* the address is expected to be a uint, not a array. */ | |
319 | address = omsg->buf[0]; | |
320 | for (i = 1; i < omsg->len; i++) | |
321 | address = (address << 8) + omsg->buf[i]; | |
322 | ||
323 | if (dmsg->flags & I2C_M_RD) | |
324 | return __i2c_read(dev->base, dmsg->addr, address, | |
325 | omsg->len, dmsg->buf, dmsg->len); | |
326 | else | |
327 | return __i2c_write(dev->base, dmsg->addr, address, | |
328 | omsg->len, dmsg->buf, dmsg->len); | |
329 | } | |
330 | ||
331 | static int lpc32xx_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) | |
332 | { | |
333 | struct lpc32xx_i2c_dev *dev = dev_get_platdata(bus); | |
334 | return __i2c_set_bus_speed(dev->base, speed, dev->index); | |
335 | } | |
336 | ||
337 | static int lpc32xx_i2c_reset(struct udevice *bus) | |
338 | { | |
339 | struct lpc32xx_i2c_dev *dev = dev_get_platdata(bus); | |
340 | ||
341 | __i2c_init(dev->base, dev->speed, 0, dev->index); | |
342 | return 0; | |
343 | } | |
344 | ||
345 | static const struct dm_i2c_ops lpc32xx_i2c_ops = { | |
346 | .xfer = lpc32xx_i2c_xfer, | |
347 | .probe_chip = lpc32xx_i2c_probe_chip, | |
348 | .deblock = lpc32xx_i2c_reset, | |
349 | .set_bus_speed = lpc32xx_i2c_set_bus_speed, | |
350 | }; | |
351 | ||
352 | U_BOOT_DRIVER(i2c_lpc32xx) = { | |
353 | .id = UCLASS_I2C, | |
354 | .name = "i2c_lpc32xx", | |
355 | .probe = lpc32xx_i2c_probe, | |
356 | .ops = &lpc32xx_i2c_ops, | |
357 | }; | |
358 | #endif /* CONFIG_DM_I2C */ |