Commit | Line | Data |
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1ab52cf9 | 1 | /* |
a0e06ea6 | 2 | * Synopsys DesignWare I2C adapter driver (master only). |
1ab52cf9 BS |
3 | * |
4 | * Based on the TI DAVINCI I2C adapter driver. | |
5 | * | |
6 | * Copyright (C) 2006 Texas Instruments. | |
7 | * Copyright (C) 2007 MontaVista Software Inc. | |
8 | * Copyright (C) 2009 Provigent Ltd. | |
9 | * | |
10 | * ---------------------------------------------------------------------------- | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or | |
15 | * (at your option) any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU General Public License for more details. | |
1ab52cf9 BS |
21 | * ---------------------------------------------------------------------------- |
22 | * | |
23 | */ | |
e68bb91b | 24 | #include <linux/export.h> |
1ab52cf9 | 25 | #include <linux/errno.h> |
1ab52cf9 | 26 | #include <linux/err.h> |
2373f6b9 | 27 | #include <linux/i2c.h> |
1ab52cf9 | 28 | #include <linux/interrupt.h> |
1ab52cf9 | 29 | #include <linux/io.h> |
18dbdda8 | 30 | #include <linux/pm_runtime.h> |
2373f6b9 | 31 | #include <linux/delay.h> |
9dd3162d | 32 | #include <linux/module.h> |
2373f6b9 | 33 | #include "i2c-designware-core.h" |
ce6eb574 | 34 | |
f3fa9f3d DB |
35 | /* |
36 | * Registers offset | |
37 | */ | |
38 | #define DW_IC_CON 0x0 | |
39 | #define DW_IC_TAR 0x4 | |
40 | #define DW_IC_DATA_CMD 0x10 | |
41 | #define DW_IC_SS_SCL_HCNT 0x14 | |
42 | #define DW_IC_SS_SCL_LCNT 0x18 | |
43 | #define DW_IC_FS_SCL_HCNT 0x1c | |
44 | #define DW_IC_FS_SCL_LCNT 0x20 | |
45 | #define DW_IC_INTR_STAT 0x2c | |
46 | #define DW_IC_INTR_MASK 0x30 | |
47 | #define DW_IC_RAW_INTR_STAT 0x34 | |
48 | #define DW_IC_RX_TL 0x38 | |
49 | #define DW_IC_TX_TL 0x3c | |
50 | #define DW_IC_CLR_INTR 0x40 | |
51 | #define DW_IC_CLR_RX_UNDER 0x44 | |
52 | #define DW_IC_CLR_RX_OVER 0x48 | |
53 | #define DW_IC_CLR_TX_OVER 0x4c | |
54 | #define DW_IC_CLR_RD_REQ 0x50 | |
55 | #define DW_IC_CLR_TX_ABRT 0x54 | |
56 | #define DW_IC_CLR_RX_DONE 0x58 | |
57 | #define DW_IC_CLR_ACTIVITY 0x5c | |
58 | #define DW_IC_CLR_STOP_DET 0x60 | |
59 | #define DW_IC_CLR_START_DET 0x64 | |
60 | #define DW_IC_CLR_GEN_CALL 0x68 | |
61 | #define DW_IC_ENABLE 0x6c | |
62 | #define DW_IC_STATUS 0x70 | |
63 | #define DW_IC_TXFLR 0x74 | |
64 | #define DW_IC_RXFLR 0x78 | |
9803f868 | 65 | #define DW_IC_SDA_HOLD 0x7c |
f3fa9f3d | 66 | #define DW_IC_TX_ABRT_SOURCE 0x80 |
3ca4ed87 | 67 | #define DW_IC_ENABLE_STATUS 0x9c |
f3fa9f3d | 68 | #define DW_IC_COMP_PARAM_1 0xf4 |
9803f868 CR |
69 | #define DW_IC_COMP_VERSION 0xf8 |
70 | #define DW_IC_SDA_HOLD_MIN_VERS 0x3131312A | |
f3fa9f3d DB |
71 | #define DW_IC_COMP_TYPE 0xfc |
72 | #define DW_IC_COMP_TYPE_VALUE 0x44570140 | |
73 | ||
74 | #define DW_IC_INTR_RX_UNDER 0x001 | |
75 | #define DW_IC_INTR_RX_OVER 0x002 | |
76 | #define DW_IC_INTR_RX_FULL 0x004 | |
77 | #define DW_IC_INTR_TX_OVER 0x008 | |
78 | #define DW_IC_INTR_TX_EMPTY 0x010 | |
79 | #define DW_IC_INTR_RD_REQ 0x020 | |
80 | #define DW_IC_INTR_TX_ABRT 0x040 | |
81 | #define DW_IC_INTR_RX_DONE 0x080 | |
82 | #define DW_IC_INTR_ACTIVITY 0x100 | |
83 | #define DW_IC_INTR_STOP_DET 0x200 | |
84 | #define DW_IC_INTR_START_DET 0x400 | |
85 | #define DW_IC_INTR_GEN_CALL 0x800 | |
86 | ||
87 | #define DW_IC_INTR_DEFAULT_MASK (DW_IC_INTR_RX_FULL | \ | |
88 | DW_IC_INTR_TX_EMPTY | \ | |
89 | DW_IC_INTR_TX_ABRT | \ | |
90 | DW_IC_INTR_STOP_DET) | |
91 | ||
92 | #define DW_IC_STATUS_ACTIVITY 0x1 | |
93 | ||
94 | #define DW_IC_ERR_TX_ABRT 0x1 | |
95 | ||
bd63ace4 CCE |
96 | #define DW_IC_TAR_10BITADDR_MASTER BIT(12) |
97 | ||
f3fa9f3d DB |
98 | /* |
99 | * status codes | |
100 | */ | |
101 | #define STATUS_IDLE 0x0 | |
102 | #define STATUS_WRITE_IN_PROGRESS 0x1 | |
103 | #define STATUS_READ_IN_PROGRESS 0x2 | |
104 | ||
105 | #define TIMEOUT 20 /* ms */ | |
106 | ||
107 | /* | |
108 | * hardware abort codes from the DW_IC_TX_ABRT_SOURCE register | |
109 | * | |
110 | * only expected abort codes are listed here | |
111 | * refer to the datasheet for the full list | |
112 | */ | |
113 | #define ABRT_7B_ADDR_NOACK 0 | |
114 | #define ABRT_10ADDR1_NOACK 1 | |
115 | #define ABRT_10ADDR2_NOACK 2 | |
116 | #define ABRT_TXDATA_NOACK 3 | |
117 | #define ABRT_GCALL_NOACK 4 | |
118 | #define ABRT_GCALL_READ 5 | |
119 | #define ABRT_SBYTE_ACKDET 7 | |
120 | #define ABRT_SBYTE_NORSTRT 9 | |
121 | #define ABRT_10B_RD_NORSTRT 10 | |
122 | #define ABRT_MASTER_DIS 11 | |
123 | #define ARB_LOST 12 | |
124 | ||
125 | #define DW_IC_TX_ABRT_7B_ADDR_NOACK (1UL << ABRT_7B_ADDR_NOACK) | |
126 | #define DW_IC_TX_ABRT_10ADDR1_NOACK (1UL << ABRT_10ADDR1_NOACK) | |
127 | #define DW_IC_TX_ABRT_10ADDR2_NOACK (1UL << ABRT_10ADDR2_NOACK) | |
128 | #define DW_IC_TX_ABRT_TXDATA_NOACK (1UL << ABRT_TXDATA_NOACK) | |
129 | #define DW_IC_TX_ABRT_GCALL_NOACK (1UL << ABRT_GCALL_NOACK) | |
130 | #define DW_IC_TX_ABRT_GCALL_READ (1UL << ABRT_GCALL_READ) | |
131 | #define DW_IC_TX_ABRT_SBYTE_ACKDET (1UL << ABRT_SBYTE_ACKDET) | |
132 | #define DW_IC_TX_ABRT_SBYTE_NORSTRT (1UL << ABRT_SBYTE_NORSTRT) | |
133 | #define DW_IC_TX_ABRT_10B_RD_NORSTRT (1UL << ABRT_10B_RD_NORSTRT) | |
134 | #define DW_IC_TX_ABRT_MASTER_DIS (1UL << ABRT_MASTER_DIS) | |
135 | #define DW_IC_TX_ARB_LOST (1UL << ARB_LOST) | |
136 | ||
137 | #define DW_IC_TX_ABRT_NOACK (DW_IC_TX_ABRT_7B_ADDR_NOACK | \ | |
138 | DW_IC_TX_ABRT_10ADDR1_NOACK | \ | |
139 | DW_IC_TX_ABRT_10ADDR2_NOACK | \ | |
140 | DW_IC_TX_ABRT_TXDATA_NOACK | \ | |
141 | DW_IC_TX_ABRT_GCALL_NOACK) | |
142 | ||
1ab52cf9 | 143 | static char *abort_sources[] = { |
a0e06ea6 | 144 | [ABRT_7B_ADDR_NOACK] = |
1ab52cf9 | 145 | "slave address not acknowledged (7bit mode)", |
a0e06ea6 | 146 | [ABRT_10ADDR1_NOACK] = |
1ab52cf9 | 147 | "first address byte not acknowledged (10bit mode)", |
a0e06ea6 | 148 | [ABRT_10ADDR2_NOACK] = |
1ab52cf9 | 149 | "second address byte not acknowledged (10bit mode)", |
a0e06ea6 | 150 | [ABRT_TXDATA_NOACK] = |
1ab52cf9 | 151 | "data not acknowledged", |
a0e06ea6 | 152 | [ABRT_GCALL_NOACK] = |
1ab52cf9 | 153 | "no acknowledgement for a general call", |
a0e06ea6 | 154 | [ABRT_GCALL_READ] = |
1ab52cf9 | 155 | "read after general call", |
a0e06ea6 | 156 | [ABRT_SBYTE_ACKDET] = |
1ab52cf9 | 157 | "start byte acknowledged", |
a0e06ea6 | 158 | [ABRT_SBYTE_NORSTRT] = |
1ab52cf9 | 159 | "trying to send start byte when restart is disabled", |
a0e06ea6 | 160 | [ABRT_10B_RD_NORSTRT] = |
1ab52cf9 | 161 | "trying to read when restart is disabled (10bit mode)", |
a0e06ea6 | 162 | [ABRT_MASTER_DIS] = |
1ab52cf9 | 163 | "trying to use disabled adapter", |
a0e06ea6 | 164 | [ARB_LOST] = |
1ab52cf9 BS |
165 | "lost arbitration", |
166 | }; | |
167 | ||
2373f6b9 | 168 | u32 dw_readl(struct dw_i2c_dev *dev, int offset) |
7f279601 | 169 | { |
a8a9f3fe | 170 | u32 value; |
18c4089e | 171 | |
a8a9f3fe SR |
172 | if (dev->accessor_flags & ACCESS_16BIT) |
173 | value = readw(dev->base + offset) | | |
174 | (readw(dev->base + offset + 2) << 16); | |
175 | else | |
176 | value = readl(dev->base + offset); | |
177 | ||
178 | if (dev->accessor_flags & ACCESS_SWAP) | |
18c4089e JHD |
179 | return swab32(value); |
180 | else | |
181 | return value; | |
7f279601 JHD |
182 | } |
183 | ||
2373f6b9 | 184 | void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset) |
7f279601 | 185 | { |
a8a9f3fe | 186 | if (dev->accessor_flags & ACCESS_SWAP) |
18c4089e JHD |
187 | b = swab32(b); |
188 | ||
a8a9f3fe SR |
189 | if (dev->accessor_flags & ACCESS_16BIT) { |
190 | writew((u16)b, dev->base + offset); | |
191 | writew((u16)(b >> 16), dev->base + offset + 2); | |
192 | } else { | |
193 | writel(b, dev->base + offset); | |
194 | } | |
7f279601 JHD |
195 | } |
196 | ||
d60c7e81 SK |
197 | static u32 |
198 | i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset) | |
199 | { | |
200 | /* | |
201 | * DesignWare I2C core doesn't seem to have solid strategy to meet | |
202 | * the tHD;STA timing spec. Configuring _HCNT based on tHIGH spec | |
203 | * will result in violation of the tHD;STA spec. | |
204 | */ | |
205 | if (cond) | |
206 | /* | |
207 | * Conditional expression: | |
208 | * | |
209 | * IC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH | |
210 | * | |
211 | * This is based on the DW manuals, and represents an ideal | |
212 | * configuration. The resulting I2C bus speed will be | |
213 | * faster than any of the others. | |
214 | * | |
215 | * If your hardware is free from tHD;STA issue, try this one. | |
216 | */ | |
6468276b | 217 | return (ic_clk * tSYMBOL + 500000) / 1000000 - 8 + offset; |
d60c7e81 SK |
218 | else |
219 | /* | |
220 | * Conditional expression: | |
221 | * | |
222 | * IC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf) | |
223 | * | |
224 | * This is just experimental rule; the tHD;STA period turned | |
225 | * out to be proportinal to (_HCNT + 3). With this setting, | |
226 | * we could meet both tHIGH and tHD;STA timing specs. | |
227 | * | |
228 | * If unsure, you'd better to take this alternative. | |
229 | * | |
230 | * The reason why we need to take into account "tf" here, | |
231 | * is the same as described in i2c_dw_scl_lcnt(). | |
232 | */ | |
6468276b RB |
233 | return (ic_clk * (tSYMBOL + tf) + 500000) / 1000000 |
234 | - 3 + offset; | |
d60c7e81 SK |
235 | } |
236 | ||
237 | static u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset) | |
238 | { | |
239 | /* | |
240 | * Conditional expression: | |
241 | * | |
242 | * IC_[FS]S_SCL_LCNT + 1 >= IC_CLK * (tLOW + tf) | |
243 | * | |
244 | * DW I2C core starts counting the SCL CNTs for the LOW period | |
245 | * of the SCL clock (tLOW) as soon as it pulls the SCL line. | |
246 | * In order to meet the tLOW timing spec, we need to take into | |
247 | * account the fall time of SCL signal (tf). Default tf value | |
248 | * should be 0.3 us, for safety. | |
249 | */ | |
6468276b | 250 | return ((ic_clk * (tLOW + tf) + 500000) / 1000000) - 1 + offset; |
d60c7e81 SK |
251 | } |
252 | ||
3ca4ed87 MW |
253 | static void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable) |
254 | { | |
255 | int timeout = 100; | |
256 | ||
257 | do { | |
258 | dw_writel(dev, enable, DW_IC_ENABLE); | |
259 | if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == enable) | |
260 | return; | |
261 | ||
262 | /* | |
263 | * Wait 10 times the signaling period of the highest I2C | |
264 | * transfer supported by the driver (for 400KHz this is | |
265 | * 25us) as described in the DesignWare I2C databook. | |
266 | */ | |
267 | usleep_range(25, 250); | |
268 | } while (timeout--); | |
269 | ||
270 | dev_warn(dev->dev, "timeout in %sabling adapter\n", | |
271 | enable ? "en" : "dis"); | |
272 | } | |
273 | ||
1ab52cf9 BS |
274 | /** |
275 | * i2c_dw_init() - initialize the designware i2c master hardware | |
276 | * @dev: device private data | |
277 | * | |
278 | * This functions configures and enables the I2C master. | |
279 | * This function is called during I2C init function, and in case of timeout at | |
280 | * run time. | |
281 | */ | |
2373f6b9 | 282 | int i2c_dw_init(struct dw_i2c_dev *dev) |
1ab52cf9 | 283 | { |
1d31b58f | 284 | u32 input_clock_khz; |
e18563fc | 285 | u32 hcnt, lcnt; |
4a423a8c | 286 | u32 reg; |
6468276b | 287 | u32 sda_falling_time, scl_falling_time; |
4a423a8c | 288 | |
1d31b58f DB |
289 | input_clock_khz = dev->get_clk_rate_khz(dev); |
290 | ||
4a423a8c DB |
291 | reg = dw_readl(dev, DW_IC_COMP_TYPE); |
292 | if (reg == ___constant_swab32(DW_IC_COMP_TYPE_VALUE)) { | |
a8a9f3fe SR |
293 | /* Configure register endianess access */ |
294 | dev->accessor_flags |= ACCESS_SWAP; | |
295 | } else if (reg == (DW_IC_COMP_TYPE_VALUE & 0x0000ffff)) { | |
296 | /* Configure register access mode 16bit */ | |
297 | dev->accessor_flags |= ACCESS_16BIT; | |
298 | } else if (reg != DW_IC_COMP_TYPE_VALUE) { | |
4a423a8c DB |
299 | dev_err(dev->dev, "Unknown Synopsys component type: " |
300 | "0x%08x\n", reg); | |
301 | return -ENODEV; | |
302 | } | |
1ab52cf9 BS |
303 | |
304 | /* Disable the adapter */ | |
3ca4ed87 | 305 | __i2c_dw_enable(dev, false); |
1ab52cf9 BS |
306 | |
307 | /* set standard and fast speed deviders for high/low periods */ | |
d60c7e81 | 308 | |
6468276b RB |
309 | sda_falling_time = dev->sda_falling_time ?: 300; /* ns */ |
310 | scl_falling_time = dev->scl_falling_time ?: 300; /* ns */ | |
311 | ||
d60c7e81 SK |
312 | /* Standard-mode */ |
313 | hcnt = i2c_dw_scl_hcnt(input_clock_khz, | |
6468276b RB |
314 | 4000, /* tHD;STA = tHIGH = 4.0 us */ |
315 | sda_falling_time, | |
d60c7e81 SK |
316 | 0, /* 0: DW default, 1: Ideal */ |
317 | 0); /* No offset */ | |
318 | lcnt = i2c_dw_scl_lcnt(input_clock_khz, | |
6468276b RB |
319 | 4700, /* tLOW = 4.7 us */ |
320 | scl_falling_time, | |
d60c7e81 | 321 | 0); /* No offset */ |
defc0b2f MW |
322 | |
323 | /* Allow platforms to specify the ideal HCNT and LCNT values */ | |
324 | if (dev->ss_hcnt && dev->ss_lcnt) { | |
325 | hcnt = dev->ss_hcnt; | |
326 | lcnt = dev->ss_lcnt; | |
327 | } | |
7f279601 JHD |
328 | dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT); |
329 | dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT); | |
d60c7e81 SK |
330 | dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt); |
331 | ||
332 | /* Fast-mode */ | |
333 | hcnt = i2c_dw_scl_hcnt(input_clock_khz, | |
6468276b RB |
334 | 600, /* tHD;STA = tHIGH = 0.6 us */ |
335 | sda_falling_time, | |
d60c7e81 SK |
336 | 0, /* 0: DW default, 1: Ideal */ |
337 | 0); /* No offset */ | |
338 | lcnt = i2c_dw_scl_lcnt(input_clock_khz, | |
6468276b RB |
339 | 1300, /* tLOW = 1.3 us */ |
340 | scl_falling_time, | |
d60c7e81 | 341 | 0); /* No offset */ |
defc0b2f MW |
342 | |
343 | if (dev->fs_hcnt && dev->fs_lcnt) { | |
344 | hcnt = dev->fs_hcnt; | |
345 | lcnt = dev->fs_lcnt; | |
346 | } | |
7f279601 JHD |
347 | dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT); |
348 | dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT); | |
d60c7e81 | 349 | dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt); |
1ab52cf9 | 350 | |
9803f868 CR |
351 | /* Configure SDA Hold Time if required */ |
352 | if (dev->sda_hold_time) { | |
353 | reg = dw_readl(dev, DW_IC_COMP_VERSION); | |
354 | if (reg >= DW_IC_SDA_HOLD_MIN_VERS) | |
355 | dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); | |
356 | else | |
357 | dev_warn(dev->dev, | |
358 | "Hardware too old to adjust SDA hold time."); | |
359 | } | |
360 | ||
4cb6d1d6 | 361 | /* Configure Tx/Rx FIFO threshold levels */ |
d39f77b0 | 362 | dw_writel(dev, dev->tx_fifo_depth / 2, DW_IC_TX_TL); |
7f279601 | 363 | dw_writel(dev, 0, DW_IC_RX_TL); |
4cb6d1d6 | 364 | |
1ab52cf9 | 365 | /* configure the i2c master */ |
e18563fc | 366 | dw_writel(dev, dev->master_cfg , DW_IC_CON); |
4a423a8c | 367 | return 0; |
1ab52cf9 | 368 | } |
e68bb91b | 369 | EXPORT_SYMBOL_GPL(i2c_dw_init); |
1ab52cf9 BS |
370 | |
371 | /* | |
372 | * Waiting for bus not busy | |
373 | */ | |
374 | static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev) | |
375 | { | |
376 | int timeout = TIMEOUT; | |
377 | ||
7f279601 | 378 | while (dw_readl(dev, DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) { |
1ab52cf9 BS |
379 | if (timeout <= 0) { |
380 | dev_warn(dev->dev, "timeout waiting for bus ready\n"); | |
381 | return -ETIMEDOUT; | |
382 | } | |
383 | timeout--; | |
1451b91f | 384 | usleep_range(1000, 1100); |
1ab52cf9 BS |
385 | } |
386 | ||
387 | return 0; | |
388 | } | |
389 | ||
81e798b7 SK |
390 | static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) |
391 | { | |
392 | struct i2c_msg *msgs = dev->msgs; | |
bd63ace4 | 393 | u32 ic_con, ic_tar = 0; |
81e798b7 SK |
394 | |
395 | /* Disable the adapter */ | |
3ca4ed87 | 396 | __i2c_dw_enable(dev, false); |
81e798b7 | 397 | |
81e798b7 | 398 | /* if the slave address is ten bit address, enable 10BITADDR */ |
7f279601 | 399 | ic_con = dw_readl(dev, DW_IC_CON); |
bd63ace4 | 400 | if (msgs[dev->msg_write_idx].flags & I2C_M_TEN) { |
81e798b7 | 401 | ic_con |= DW_IC_CON_10BITADDR_MASTER; |
bd63ace4 CCE |
402 | /* |
403 | * If I2C_DYNAMIC_TAR_UPDATE is set, the 10-bit addressing | |
404 | * mode has to be enabled via bit 12 of IC_TAR register. | |
405 | * We set it always as I2C_DYNAMIC_TAR_UPDATE can't be | |
406 | * detected from registers. | |
407 | */ | |
408 | ic_tar = DW_IC_TAR_10BITADDR_MASTER; | |
409 | } else { | |
81e798b7 | 410 | ic_con &= ~DW_IC_CON_10BITADDR_MASTER; |
bd63ace4 CCE |
411 | } |
412 | ||
7f279601 | 413 | dw_writel(dev, ic_con, DW_IC_CON); |
81e798b7 | 414 | |
bd63ace4 CCE |
415 | /* |
416 | * Set the slave (target) address and enable 10-bit addressing mode | |
417 | * if applicable. | |
418 | */ | |
419 | dw_writel(dev, msgs[dev->msg_write_idx].addr | ic_tar, DW_IC_TAR); | |
420 | ||
47bb27e7 DW |
421 | /* enforce disabled interrupts (due to HW issues) */ |
422 | i2c_dw_disable_int(dev); | |
423 | ||
81e798b7 | 424 | /* Enable the adapter */ |
3ca4ed87 | 425 | __i2c_dw_enable(dev, true); |
201d6a70 | 426 | |
2a2d95e9 MW |
427 | /* Clear and enable interrupts */ |
428 | i2c_dw_clear_int(dev); | |
7f279601 | 429 | dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK); |
81e798b7 SK |
430 | } |
431 | ||
1ab52cf9 | 432 | /* |
201d6a70 SK |
433 | * Initiate (and continue) low level master read/write transaction. |
434 | * This function is only called from i2c_dw_isr, and pumping i2c_msg | |
435 | * messages into the tx buffer. Even if the size of i2c_msg data is | |
436 | * longer than the size of the tx buffer, it handles everything. | |
1ab52cf9 | 437 | */ |
bccd780f | 438 | static void |
e77cf232 | 439 | i2c_dw_xfer_msg(struct dw_i2c_dev *dev) |
1ab52cf9 | 440 | { |
1ab52cf9 | 441 | struct i2c_msg *msgs = dev->msgs; |
81e798b7 | 442 | u32 intr_mask; |
ae72222d | 443 | int tx_limit, rx_limit; |
ed5e1dd5 SK |
444 | u32 addr = msgs[dev->msg_write_idx].addr; |
445 | u32 buf_len = dev->tx_buf_len; | |
69932487 | 446 | u8 *buf = dev->tx_buf; |
82564245 | 447 | bool need_restart = false; |
1ab52cf9 | 448 | |
201d6a70 | 449 | intr_mask = DW_IC_INTR_DEFAULT_MASK; |
c70c5cd3 | 450 | |
6d2ea487 | 451 | for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) { |
a0e06ea6 SK |
452 | /* |
453 | * if target address has changed, we need to | |
1ab52cf9 BS |
454 | * reprogram the target address in the i2c |
455 | * adapter when we are done with this transfer | |
456 | */ | |
8f588e40 SK |
457 | if (msgs[dev->msg_write_idx].addr != addr) { |
458 | dev_err(dev->dev, | |
459 | "%s: invalid target address\n", __func__); | |
460 | dev->msg_err = -EINVAL; | |
461 | break; | |
462 | } | |
1ab52cf9 BS |
463 | |
464 | if (msgs[dev->msg_write_idx].len == 0) { | |
465 | dev_err(dev->dev, | |
466 | "%s: invalid message length\n", __func__); | |
467 | dev->msg_err = -EINVAL; | |
8f588e40 | 468 | break; |
1ab52cf9 BS |
469 | } |
470 | ||
471 | if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) { | |
472 | /* new i2c_msg */ | |
26ea15b1 | 473 | buf = msgs[dev->msg_write_idx].buf; |
1ab52cf9 | 474 | buf_len = msgs[dev->msg_write_idx].len; |
82564245 CCE |
475 | |
476 | /* If both IC_EMPTYFIFO_HOLD_MASTER_EN and | |
477 | * IC_RESTART_EN are set, we must manually | |
478 | * set restart bit between messages. | |
479 | */ | |
480 | if ((dev->master_cfg & DW_IC_CON_RESTART_EN) && | |
481 | (dev->msg_write_idx > 0)) | |
482 | need_restart = true; | |
1ab52cf9 BS |
483 | } |
484 | ||
7f279601 JHD |
485 | tx_limit = dev->tx_fifo_depth - dw_readl(dev, DW_IC_TXFLR); |
486 | rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR); | |
ae72222d | 487 | |
1ab52cf9 | 488 | while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) { |
17a76b4b MW |
489 | u32 cmd = 0; |
490 | ||
491 | /* | |
492 | * If IC_EMPTYFIFO_HOLD_MASTER_EN is set we must | |
493 | * manually set the stop bit. However, it cannot be | |
494 | * detected from the registers so we set it always | |
495 | * when writing/reading the last byte. | |
496 | */ | |
497 | if (dev->msg_write_idx == dev->msgs_num - 1 && | |
498 | buf_len == 1) | |
499 | cmd |= BIT(9); | |
500 | ||
82564245 CCE |
501 | if (need_restart) { |
502 | cmd |= BIT(10); | |
503 | need_restart = false; | |
504 | } | |
505 | ||
1ab52cf9 | 506 | if (msgs[dev->msg_write_idx].flags & I2C_M_RD) { |
e6f34cea JA |
507 | |
508 | /* avoid rx buffer overrun */ | |
509 | if (rx_limit - dev->rx_outstanding <= 0) | |
510 | break; | |
511 | ||
17a76b4b | 512 | dw_writel(dev, cmd | 0x100, DW_IC_DATA_CMD); |
1ab52cf9 | 513 | rx_limit--; |
e6f34cea | 514 | dev->rx_outstanding++; |
1ab52cf9 | 515 | } else |
17a76b4b | 516 | dw_writel(dev, cmd | *buf++, DW_IC_DATA_CMD); |
1ab52cf9 BS |
517 | tx_limit--; buf_len--; |
518 | } | |
c70c5cd3 | 519 | |
26ea15b1 | 520 | dev->tx_buf = buf; |
c70c5cd3 SK |
521 | dev->tx_buf_len = buf_len; |
522 | ||
523 | if (buf_len > 0) { | |
524 | /* more bytes to be written */ | |
c70c5cd3 SK |
525 | dev->status |= STATUS_WRITE_IN_PROGRESS; |
526 | break; | |
69151e53 | 527 | } else |
c70c5cd3 | 528 | dev->status &= ~STATUS_WRITE_IN_PROGRESS; |
1ab52cf9 BS |
529 | } |
530 | ||
69151e53 SK |
531 | /* |
532 | * If i2c_msg index search is completed, we don't need TX_EMPTY | |
533 | * interrupt any more. | |
534 | */ | |
535 | if (dev->msg_write_idx == dev->msgs_num) | |
536 | intr_mask &= ~DW_IC_INTR_TX_EMPTY; | |
537 | ||
8f588e40 SK |
538 | if (dev->msg_err) |
539 | intr_mask = 0; | |
540 | ||
2373f6b9 | 541 | dw_writel(dev, intr_mask, DW_IC_INTR_MASK); |
1ab52cf9 BS |
542 | } |
543 | ||
544 | static void | |
78839bd0 | 545 | i2c_dw_read(struct dw_i2c_dev *dev) |
1ab52cf9 | 546 | { |
1ab52cf9 | 547 | struct i2c_msg *msgs = dev->msgs; |
ae72222d | 548 | int rx_valid; |
1ab52cf9 | 549 | |
6d2ea487 | 550 | for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) { |
ed5e1dd5 | 551 | u32 len; |
1ab52cf9 BS |
552 | u8 *buf; |
553 | ||
554 | if (!(msgs[dev->msg_read_idx].flags & I2C_M_RD)) | |
555 | continue; | |
556 | ||
1ab52cf9 BS |
557 | if (!(dev->status & STATUS_READ_IN_PROGRESS)) { |
558 | len = msgs[dev->msg_read_idx].len; | |
559 | buf = msgs[dev->msg_read_idx].buf; | |
560 | } else { | |
561 | len = dev->rx_buf_len; | |
562 | buf = dev->rx_buf; | |
563 | } | |
564 | ||
7f279601 | 565 | rx_valid = dw_readl(dev, DW_IC_RXFLR); |
ae72222d | 566 | |
e6f34cea | 567 | for (; len > 0 && rx_valid > 0; len--, rx_valid--) { |
7f279601 | 568 | *buf++ = dw_readl(dev, DW_IC_DATA_CMD); |
e6f34cea JA |
569 | dev->rx_outstanding--; |
570 | } | |
1ab52cf9 BS |
571 | |
572 | if (len > 0) { | |
573 | dev->status |= STATUS_READ_IN_PROGRESS; | |
574 | dev->rx_buf_len = len; | |
575 | dev->rx_buf = buf; | |
576 | return; | |
577 | } else | |
578 | dev->status &= ~STATUS_READ_IN_PROGRESS; | |
579 | } | |
580 | } | |
581 | ||
ce6eb574 SK |
582 | static int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev) |
583 | { | |
584 | unsigned long abort_source = dev->abort_source; | |
585 | int i; | |
586 | ||
6d1ea0f6 | 587 | if (abort_source & DW_IC_TX_ABRT_NOACK) { |
984b3f57 | 588 | for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) |
6d1ea0f6 SK |
589 | dev_dbg(dev->dev, |
590 | "%s: %s\n", __func__, abort_sources[i]); | |
591 | return -EREMOTEIO; | |
592 | } | |
593 | ||
984b3f57 | 594 | for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) |
ce6eb574 SK |
595 | dev_err(dev->dev, "%s: %s\n", __func__, abort_sources[i]); |
596 | ||
597 | if (abort_source & DW_IC_TX_ARB_LOST) | |
598 | return -EAGAIN; | |
ce6eb574 SK |
599 | else if (abort_source & DW_IC_TX_ABRT_GCALL_READ) |
600 | return -EINVAL; /* wrong msgs[] data */ | |
601 | else | |
602 | return -EIO; | |
603 | } | |
604 | ||
1ab52cf9 BS |
605 | /* |
606 | * Prepare controller for a transaction and call i2c_dw_xfer_msg | |
607 | */ | |
2373f6b9 | 608 | int |
1ab52cf9 BS |
609 | i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) |
610 | { | |
611 | struct dw_i2c_dev *dev = i2c_get_adapdata(adap); | |
612 | int ret; | |
613 | ||
614 | dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num); | |
615 | ||
616 | mutex_lock(&dev->lock); | |
18dbdda8 | 617 | pm_runtime_get_sync(dev->dev); |
1ab52cf9 | 618 | |
16735d02 | 619 | reinit_completion(&dev->cmd_complete); |
1ab52cf9 BS |
620 | dev->msgs = msgs; |
621 | dev->msgs_num = num; | |
622 | dev->cmd_err = 0; | |
623 | dev->msg_write_idx = 0; | |
624 | dev->msg_read_idx = 0; | |
625 | dev->msg_err = 0; | |
626 | dev->status = STATUS_IDLE; | |
ce6eb574 | 627 | dev->abort_source = 0; |
e6f34cea | 628 | dev->rx_outstanding = 0; |
1ab52cf9 BS |
629 | |
630 | ret = i2c_dw_wait_bus_not_busy(dev); | |
631 | if (ret < 0) | |
632 | goto done; | |
633 | ||
634 | /* start the transfers */ | |
81e798b7 | 635 | i2c_dw_xfer_init(dev); |
1ab52cf9 BS |
636 | |
637 | /* wait for tx to complete */ | |
e42dba56 | 638 | ret = wait_for_completion_timeout(&dev->cmd_complete, HZ); |
1ab52cf9 BS |
639 | if (ret == 0) { |
640 | dev_err(dev->dev, "controller timed out\n"); | |
38d7fade | 641 | /* i2c_dw_init implicitly disables the adapter */ |
1ab52cf9 BS |
642 | i2c_dw_init(dev); |
643 | ret = -ETIMEDOUT; | |
644 | goto done; | |
e42dba56 | 645 | } |
1ab52cf9 | 646 | |
38d7fade CR |
647 | /* |
648 | * We must disable the adapter before unlocking the &dev->lock mutex | |
649 | * below. Otherwise the hardware might continue generating interrupts | |
650 | * which in turn causes a race condition with the following transfer. | |
651 | * Needs some more investigation if the additional interrupts are | |
652 | * a hardware bug or this driver doesn't handle them correctly yet. | |
653 | */ | |
654 | __i2c_dw_enable(dev, false); | |
655 | ||
1ab52cf9 BS |
656 | if (dev->msg_err) { |
657 | ret = dev->msg_err; | |
658 | goto done; | |
659 | } | |
660 | ||
661 | /* no error */ | |
662 | if (likely(!dev->cmd_err)) { | |
1ab52cf9 BS |
663 | ret = num; |
664 | goto done; | |
665 | } | |
666 | ||
667 | /* We have an error */ | |
668 | if (dev->cmd_err == DW_IC_ERR_TX_ABRT) { | |
ce6eb574 SK |
669 | ret = i2c_dw_handle_tx_abort(dev); |
670 | goto done; | |
1ab52cf9 BS |
671 | } |
672 | ret = -EIO; | |
673 | ||
674 | done: | |
43452335 MW |
675 | pm_runtime_mark_last_busy(dev->dev); |
676 | pm_runtime_put_autosuspend(dev->dev); | |
1ab52cf9 BS |
677 | mutex_unlock(&dev->lock); |
678 | ||
679 | return ret; | |
680 | } | |
e68bb91b | 681 | EXPORT_SYMBOL_GPL(i2c_dw_xfer); |
1ab52cf9 | 682 | |
2373f6b9 | 683 | u32 i2c_dw_func(struct i2c_adapter *adap) |
1ab52cf9 | 684 | { |
2fa8326b DB |
685 | struct dw_i2c_dev *dev = i2c_get_adapdata(adap); |
686 | return dev->functionality; | |
1ab52cf9 | 687 | } |
e68bb91b | 688 | EXPORT_SYMBOL_GPL(i2c_dw_func); |
1ab52cf9 | 689 | |
e28000a3 SK |
690 | static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev) |
691 | { | |
692 | u32 stat; | |
693 | ||
694 | /* | |
695 | * The IC_INTR_STAT register just indicates "enabled" interrupts. | |
696 | * Ths unmasked raw version of interrupt status bits are available | |
697 | * in the IC_RAW_INTR_STAT register. | |
698 | * | |
699 | * That is, | |
2373f6b9 | 700 | * stat = dw_readl(IC_INTR_STAT); |
e28000a3 | 701 | * equals to, |
2373f6b9 | 702 | * stat = dw_readl(IC_RAW_INTR_STAT) & dw_readl(IC_INTR_MASK); |
e28000a3 SK |
703 | * |
704 | * The raw version might be useful for debugging purposes. | |
705 | */ | |
7f279601 | 706 | stat = dw_readl(dev, DW_IC_INTR_STAT); |
e28000a3 SK |
707 | |
708 | /* | |
709 | * Do not use the IC_CLR_INTR register to clear interrupts, or | |
710 | * you'll miss some interrupts, triggered during the period from | |
2373f6b9 | 711 | * dw_readl(IC_INTR_STAT) to dw_readl(IC_CLR_INTR). |
e28000a3 SK |
712 | * |
713 | * Instead, use the separately-prepared IC_CLR_* registers. | |
714 | */ | |
715 | if (stat & DW_IC_INTR_RX_UNDER) | |
7f279601 | 716 | dw_readl(dev, DW_IC_CLR_RX_UNDER); |
e28000a3 | 717 | if (stat & DW_IC_INTR_RX_OVER) |
7f279601 | 718 | dw_readl(dev, DW_IC_CLR_RX_OVER); |
e28000a3 | 719 | if (stat & DW_IC_INTR_TX_OVER) |
7f279601 | 720 | dw_readl(dev, DW_IC_CLR_TX_OVER); |
e28000a3 | 721 | if (stat & DW_IC_INTR_RD_REQ) |
7f279601 | 722 | dw_readl(dev, DW_IC_CLR_RD_REQ); |
e28000a3 SK |
723 | if (stat & DW_IC_INTR_TX_ABRT) { |
724 | /* | |
725 | * The IC_TX_ABRT_SOURCE register is cleared whenever | |
726 | * the IC_CLR_TX_ABRT is read. Preserve it beforehand. | |
727 | */ | |
7f279601 JHD |
728 | dev->abort_source = dw_readl(dev, DW_IC_TX_ABRT_SOURCE); |
729 | dw_readl(dev, DW_IC_CLR_TX_ABRT); | |
e28000a3 SK |
730 | } |
731 | if (stat & DW_IC_INTR_RX_DONE) | |
7f279601 | 732 | dw_readl(dev, DW_IC_CLR_RX_DONE); |
e28000a3 | 733 | if (stat & DW_IC_INTR_ACTIVITY) |
7f279601 | 734 | dw_readl(dev, DW_IC_CLR_ACTIVITY); |
e28000a3 | 735 | if (stat & DW_IC_INTR_STOP_DET) |
7f279601 | 736 | dw_readl(dev, DW_IC_CLR_STOP_DET); |
e28000a3 | 737 | if (stat & DW_IC_INTR_START_DET) |
7f279601 | 738 | dw_readl(dev, DW_IC_CLR_START_DET); |
e28000a3 | 739 | if (stat & DW_IC_INTR_GEN_CALL) |
7f279601 | 740 | dw_readl(dev, DW_IC_CLR_GEN_CALL); |
e28000a3 SK |
741 | |
742 | return stat; | |
743 | } | |
744 | ||
1ab52cf9 BS |
745 | /* |
746 | * Interrupt service routine. This gets called whenever an I2C interrupt | |
747 | * occurs. | |
748 | */ | |
2373f6b9 | 749 | irqreturn_t i2c_dw_isr(int this_irq, void *dev_id) |
1ab52cf9 BS |
750 | { |
751 | struct dw_i2c_dev *dev = dev_id; | |
af06cf6c DB |
752 | u32 stat, enabled; |
753 | ||
754 | enabled = dw_readl(dev, DW_IC_ENABLE); | |
755 | stat = dw_readl(dev, DW_IC_RAW_INTR_STAT); | |
756 | dev_dbg(dev->dev, "%s: %s enabled= 0x%x stat=0x%x\n", __func__, | |
757 | dev->adapter.name, enabled, stat); | |
758 | if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY)) | |
759 | return IRQ_NONE; | |
1ab52cf9 | 760 | |
e28000a3 | 761 | stat = i2c_dw_read_clear_intrbits(dev); |
e28000a3 | 762 | |
1ab52cf9 | 763 | if (stat & DW_IC_INTR_TX_ABRT) { |
1ab52cf9 BS |
764 | dev->cmd_err |= DW_IC_ERR_TX_ABRT; |
765 | dev->status = STATUS_IDLE; | |
597fe310 SK |
766 | |
767 | /* | |
768 | * Anytime TX_ABRT is set, the contents of the tx/rx | |
769 | * buffers are flushed. Make sure to skip them. | |
770 | */ | |
7f279601 | 771 | dw_writel(dev, 0, DW_IC_INTR_MASK); |
597fe310 | 772 | goto tx_aborted; |
07745399 SK |
773 | } |
774 | ||
21a89d41 | 775 | if (stat & DW_IC_INTR_RX_FULL) |
07745399 | 776 | i2c_dw_read(dev); |
21a89d41 SK |
777 | |
778 | if (stat & DW_IC_INTR_TX_EMPTY) | |
07745399 | 779 | i2c_dw_xfer_msg(dev); |
07745399 SK |
780 | |
781 | /* | |
782 | * No need to modify or disable the interrupt mask here. | |
783 | * i2c_dw_xfer_msg() will take care of it according to | |
784 | * the current transmit status. | |
785 | */ | |
1ab52cf9 | 786 | |
597fe310 | 787 | tx_aborted: |
8f588e40 | 788 | if ((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET)) || dev->msg_err) |
1ab52cf9 BS |
789 | complete(&dev->cmd_complete); |
790 | ||
791 | return IRQ_HANDLED; | |
792 | } | |
e68bb91b | 793 | EXPORT_SYMBOL_GPL(i2c_dw_isr); |
f3fa9f3d DB |
794 | |
795 | void i2c_dw_enable(struct dw_i2c_dev *dev) | |
796 | { | |
797 | /* Enable the adapter */ | |
3ca4ed87 | 798 | __i2c_dw_enable(dev, true); |
f3fa9f3d | 799 | } |
e68bb91b | 800 | EXPORT_SYMBOL_GPL(i2c_dw_enable); |
f3fa9f3d | 801 | |
18dbdda8 | 802 | u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev) |
f3fa9f3d | 803 | { |
18dbdda8 DB |
804 | return dw_readl(dev, DW_IC_ENABLE); |
805 | } | |
e68bb91b | 806 | EXPORT_SYMBOL_GPL(i2c_dw_is_enabled); |
f3fa9f3d | 807 | |
18dbdda8 DB |
808 | void i2c_dw_disable(struct dw_i2c_dev *dev) |
809 | { | |
f3fa9f3d | 810 | /* Disable controller */ |
3ca4ed87 | 811 | __i2c_dw_enable(dev, false); |
f3fa9f3d DB |
812 | |
813 | /* Disable all interupts */ | |
814 | dw_writel(dev, 0, DW_IC_INTR_MASK); | |
815 | dw_readl(dev, DW_IC_CLR_INTR); | |
816 | } | |
e68bb91b | 817 | EXPORT_SYMBOL_GPL(i2c_dw_disable); |
f3fa9f3d DB |
818 | |
819 | void i2c_dw_clear_int(struct dw_i2c_dev *dev) | |
820 | { | |
821 | dw_readl(dev, DW_IC_CLR_INTR); | |
822 | } | |
e68bb91b | 823 | EXPORT_SYMBOL_GPL(i2c_dw_clear_int); |
f3fa9f3d DB |
824 | |
825 | void i2c_dw_disable_int(struct dw_i2c_dev *dev) | |
826 | { | |
827 | dw_writel(dev, 0, DW_IC_INTR_MASK); | |
828 | } | |
e68bb91b | 829 | EXPORT_SYMBOL_GPL(i2c_dw_disable_int); |
f3fa9f3d DB |
830 | |
831 | u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev) | |
832 | { | |
833 | return dw_readl(dev, DW_IC_COMP_PARAM_1); | |
834 | } | |
e68bb91b | 835 | EXPORT_SYMBOL_GPL(i2c_dw_read_comp_param); |
9dd3162d MW |
836 | |
837 | MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core"); | |
838 | MODULE_LICENSE("GPL"); |