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db811ca0 CC |
1 | /* |
2 | * drivers/i2c/busses/i2c-tegra.c | |
3 | * | |
4 | * Copyright (C) 2010 Google, Inc. | |
5 | * Author: Colin Cross <ccross@android.com> | |
6 | * | |
7 | * This software is licensed under the terms of the GNU General Public | |
8 | * License version 2, as published by the Free Software Foundation, and | |
9 | * may be copied, distributed, and modified under those terms. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | */ | |
17 | ||
18 | #include <linux/kernel.h> | |
19 | #include <linux/init.h> | |
20 | #include <linux/platform_device.h> | |
21 | #include <linux/clk.h> | |
22 | #include <linux/err.h> | |
23 | #include <linux/i2c.h> | |
24 | #include <linux/io.h> | |
25 | #include <linux/interrupt.h> | |
26 | #include <linux/delay.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/i2c-tegra.h> | |
5c470f39 | 29 | #include <linux/of_i2c.h> |
93cf5d75 | 30 | #include <linux/module.h> |
db811ca0 CC |
31 | |
32 | #include <asm/unaligned.h> | |
33 | ||
34 | #include <mach/clk.h> | |
35 | ||
36 | #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) | |
37 | #define BYTES_PER_FIFO_WORD 4 | |
38 | ||
39 | #define I2C_CNFG 0x000 | |
40abcf77 | 40 | #define I2C_CNFG_DEBOUNCE_CNT_SHIFT 12 |
db811ca0 CC |
41 | #define I2C_CNFG_PACKET_MODE_EN (1<<10) |
42 | #define I2C_CNFG_NEW_MASTER_FSM (1<<11) | |
cb63c62d | 43 | #define I2C_STATUS 0x01C |
db811ca0 | 44 | #define I2C_SL_CNFG 0x020 |
5afa9d35 | 45 | #define I2C_SL_CNFG_NACK (1<<1) |
db811ca0 CC |
46 | #define I2C_SL_CNFG_NEWSL (1<<2) |
47 | #define I2C_SL_ADDR1 0x02c | |
5afa9d35 | 48 | #define I2C_SL_ADDR2 0x030 |
db811ca0 CC |
49 | #define I2C_TX_FIFO 0x050 |
50 | #define I2C_RX_FIFO 0x054 | |
51 | #define I2C_PACKET_TRANSFER_STATUS 0x058 | |
52 | #define I2C_FIFO_CONTROL 0x05c | |
53 | #define I2C_FIFO_CONTROL_TX_FLUSH (1<<1) | |
54 | #define I2C_FIFO_CONTROL_RX_FLUSH (1<<0) | |
55 | #define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5 | |
56 | #define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2 | |
57 | #define I2C_FIFO_STATUS 0x060 | |
58 | #define I2C_FIFO_STATUS_TX_MASK 0xF0 | |
59 | #define I2C_FIFO_STATUS_TX_SHIFT 4 | |
60 | #define I2C_FIFO_STATUS_RX_MASK 0x0F | |
61 | #define I2C_FIFO_STATUS_RX_SHIFT 0 | |
62 | #define I2C_INT_MASK 0x064 | |
63 | #define I2C_INT_STATUS 0x068 | |
64 | #define I2C_INT_PACKET_XFER_COMPLETE (1<<7) | |
65 | #define I2C_INT_ALL_PACKETS_XFER_COMPLETE (1<<6) | |
66 | #define I2C_INT_TX_FIFO_OVERFLOW (1<<5) | |
67 | #define I2C_INT_RX_FIFO_UNDERFLOW (1<<4) | |
68 | #define I2C_INT_NO_ACK (1<<3) | |
69 | #define I2C_INT_ARBITRATION_LOST (1<<2) | |
70 | #define I2C_INT_TX_FIFO_DATA_REQ (1<<1) | |
71 | #define I2C_INT_RX_FIFO_DATA_REQ (1<<0) | |
72 | #define I2C_CLK_DIVISOR 0x06c | |
73 | ||
74 | #define DVC_CTRL_REG1 0x000 | |
75 | #define DVC_CTRL_REG1_INTR_EN (1<<10) | |
76 | #define DVC_CTRL_REG2 0x004 | |
77 | #define DVC_CTRL_REG3 0x008 | |
78 | #define DVC_CTRL_REG3_SW_PROG (1<<26) | |
79 | #define DVC_CTRL_REG3_I2C_DONE_INTR_EN (1<<30) | |
80 | #define DVC_STATUS 0x00c | |
81 | #define DVC_STATUS_I2C_DONE_INTR (1<<30) | |
82 | ||
83 | #define I2C_ERR_NONE 0x00 | |
84 | #define I2C_ERR_NO_ACK 0x01 | |
85 | #define I2C_ERR_ARBITRATION_LOST 0x02 | |
cb63c62d | 86 | #define I2C_ERR_UNKNOWN_INTERRUPT 0x04 |
db811ca0 CC |
87 | |
88 | #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28 | |
89 | #define PACKET_HEADER0_PACKET_ID_SHIFT 16 | |
90 | #define PACKET_HEADER0_CONT_ID_SHIFT 12 | |
91 | #define PACKET_HEADER0_PROTOCOL_I2C (1<<4) | |
92 | ||
93 | #define I2C_HEADER_HIGHSPEED_MODE (1<<22) | |
94 | #define I2C_HEADER_CONT_ON_NAK (1<<21) | |
95 | #define I2C_HEADER_SEND_START_BYTE (1<<20) | |
96 | #define I2C_HEADER_READ (1<<19) | |
97 | #define I2C_HEADER_10BIT_ADDR (1<<18) | |
98 | #define I2C_HEADER_IE_ENABLE (1<<17) | |
99 | #define I2C_HEADER_REPEAT_START (1<<16) | |
100 | #define I2C_HEADER_MASTER_ADDR_SHIFT 12 | |
101 | #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 | |
102 | ||
103 | /** | |
104 | * struct tegra_i2c_dev - per device i2c context | |
105 | * @dev: device reference for power management | |
106 | * @adapter: core i2c layer adapter information | |
107 | * @clk: clock reference for i2c controller | |
108 | * @i2c_clk: clock reference for i2c bus | |
109 | * @iomem: memory resource for registers | |
110 | * @base: ioremapped registers cookie | |
111 | * @cont_id: i2c controller id, used for for packet header | |
112 | * @irq: irq number of transfer complete interrupt | |
113 | * @is_dvc: identifies the DVC i2c controller, has a different register layout | |
114 | * @msg_complete: transfer completion notifier | |
115 | * @msg_err: error code for completed message | |
116 | * @msg_buf: pointer to current message data | |
117 | * @msg_buf_remaining: size of unsent data in the message buffer | |
118 | * @msg_read: identifies read transfers | |
119 | * @bus_clk_rate: current i2c bus clock rate | |
120 | * @is_suspended: prevents i2c controller accesses after suspend is called | |
121 | */ | |
122 | struct tegra_i2c_dev { | |
123 | struct device *dev; | |
124 | struct i2c_adapter adapter; | |
125 | struct clk *clk; | |
126 | struct clk *i2c_clk; | |
127 | struct resource *iomem; | |
128 | void __iomem *base; | |
129 | int cont_id; | |
130 | int irq; | |
cb63c62d | 131 | bool irq_disabled; |
db811ca0 CC |
132 | int is_dvc; |
133 | struct completion msg_complete; | |
134 | int msg_err; | |
135 | u8 *msg_buf; | |
136 | size_t msg_buf_remaining; | |
137 | int msg_read; | |
138 | unsigned long bus_clk_rate; | |
139 | bool is_suspended; | |
140 | }; | |
141 | ||
142 | static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned long reg) | |
143 | { | |
144 | writel(val, i2c_dev->base + reg); | |
145 | } | |
146 | ||
147 | static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) | |
148 | { | |
149 | return readl(i2c_dev->base + reg); | |
150 | } | |
151 | ||
152 | /* | |
153 | * i2c_writel and i2c_readl will offset the register if necessary to talk | |
154 | * to the I2C block inside the DVC block | |
155 | */ | |
156 | static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, | |
157 | unsigned long reg) | |
158 | { | |
159 | if (i2c_dev->is_dvc) | |
160 | reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40; | |
161 | return reg; | |
162 | } | |
163 | ||
164 | static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, | |
165 | unsigned long reg) | |
166 | { | |
167 | writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); | |
168 | } | |
169 | ||
170 | static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) | |
171 | { | |
172 | return readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); | |
173 | } | |
174 | ||
175 | static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, | |
176 | unsigned long reg, int len) | |
177 | { | |
178 | writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); | |
179 | } | |
180 | ||
181 | static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, | |
182 | unsigned long reg, int len) | |
183 | { | |
184 | readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); | |
185 | } | |
186 | ||
187 | static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) | |
188 | { | |
189 | u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK); | |
190 | int_mask &= ~mask; | |
191 | i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); | |
192 | } | |
193 | ||
194 | static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) | |
195 | { | |
196 | u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK); | |
197 | int_mask |= mask; | |
198 | i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); | |
199 | } | |
200 | ||
201 | static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) | |
202 | { | |
203 | unsigned long timeout = jiffies + HZ; | |
204 | u32 val = i2c_readl(i2c_dev, I2C_FIFO_CONTROL); | |
205 | val |= I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH; | |
206 | i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); | |
207 | ||
208 | while (i2c_readl(i2c_dev, I2C_FIFO_CONTROL) & | |
209 | (I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH)) { | |
210 | if (time_after(jiffies, timeout)) { | |
211 | dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n"); | |
212 | return -ETIMEDOUT; | |
213 | } | |
214 | msleep(1); | |
215 | } | |
216 | return 0; | |
217 | } | |
218 | ||
219 | static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) | |
220 | { | |
221 | u32 val; | |
222 | int rx_fifo_avail; | |
223 | u8 *buf = i2c_dev->msg_buf; | |
224 | size_t buf_remaining = i2c_dev->msg_buf_remaining; | |
225 | int words_to_transfer; | |
226 | ||
227 | val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); | |
228 | rx_fifo_avail = (val & I2C_FIFO_STATUS_RX_MASK) >> | |
229 | I2C_FIFO_STATUS_RX_SHIFT; | |
230 | ||
231 | /* Rounds down to not include partial word at the end of buf */ | |
232 | words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; | |
233 | if (words_to_transfer > rx_fifo_avail) | |
234 | words_to_transfer = rx_fifo_avail; | |
235 | ||
236 | i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer); | |
237 | ||
238 | buf += words_to_transfer * BYTES_PER_FIFO_WORD; | |
239 | buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; | |
240 | rx_fifo_avail -= words_to_transfer; | |
241 | ||
242 | /* | |
243 | * If there is a partial word at the end of buf, handle it manually to | |
244 | * prevent overwriting past the end of buf | |
245 | */ | |
246 | if (rx_fifo_avail > 0 && buf_remaining > 0) { | |
247 | BUG_ON(buf_remaining > 3); | |
248 | val = i2c_readl(i2c_dev, I2C_RX_FIFO); | |
249 | memcpy(buf, &val, buf_remaining); | |
250 | buf_remaining = 0; | |
251 | rx_fifo_avail--; | |
252 | } | |
253 | ||
254 | BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0); | |
255 | i2c_dev->msg_buf_remaining = buf_remaining; | |
256 | i2c_dev->msg_buf = buf; | |
257 | return 0; | |
258 | } | |
259 | ||
260 | static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) | |
261 | { | |
262 | u32 val; | |
263 | int tx_fifo_avail; | |
264 | u8 *buf = i2c_dev->msg_buf; | |
265 | size_t buf_remaining = i2c_dev->msg_buf_remaining; | |
266 | int words_to_transfer; | |
267 | ||
268 | val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); | |
269 | tx_fifo_avail = (val & I2C_FIFO_STATUS_TX_MASK) >> | |
270 | I2C_FIFO_STATUS_TX_SHIFT; | |
271 | ||
272 | /* Rounds down to not include partial word at the end of buf */ | |
273 | words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; | |
db811ca0 | 274 | |
96219c3a DA |
275 | /* It's very common to have < 4 bytes, so optimize that case. */ |
276 | if (words_to_transfer) { | |
277 | if (words_to_transfer > tx_fifo_avail) | |
278 | words_to_transfer = tx_fifo_avail; | |
279 | ||
280 | /* | |
281 | * Update state before writing to FIFO. If this casues us | |
282 | * to finish writing all bytes (AKA buf_remaining goes to 0) we | |
283 | * have a potential for an interrupt (PACKET_XFER_COMPLETE is | |
284 | * not maskable). We need to make sure that the isr sees | |
285 | * buf_remaining as 0 and doesn't call us back re-entrantly. | |
286 | */ | |
287 | buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; | |
288 | tx_fifo_avail -= words_to_transfer; | |
289 | i2c_dev->msg_buf_remaining = buf_remaining; | |
290 | i2c_dev->msg_buf = buf + | |
291 | words_to_transfer * BYTES_PER_FIFO_WORD; | |
292 | barrier(); | |
293 | ||
294 | i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); | |
295 | ||
296 | buf += words_to_transfer * BYTES_PER_FIFO_WORD; | |
297 | } | |
db811ca0 CC |
298 | |
299 | /* | |
300 | * If there is a partial word at the end of buf, handle it manually to | |
301 | * prevent reading past the end of buf, which could cross a page | |
302 | * boundary and fault. | |
303 | */ | |
304 | if (tx_fifo_avail > 0 && buf_remaining > 0) { | |
305 | BUG_ON(buf_remaining > 3); | |
306 | memcpy(&val, buf, buf_remaining); | |
96219c3a DA |
307 | |
308 | /* Again update before writing to FIFO to make sure isr sees. */ | |
309 | i2c_dev->msg_buf_remaining = 0; | |
310 | i2c_dev->msg_buf = NULL; | |
311 | barrier(); | |
312 | ||
db811ca0 | 313 | i2c_writel(i2c_dev, val, I2C_TX_FIFO); |
db811ca0 CC |
314 | } |
315 | ||
db811ca0 CC |
316 | return 0; |
317 | } | |
318 | ||
319 | /* | |
320 | * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller) | |
321 | * block. This block is identical to the rest of the I2C blocks, except that | |
322 | * it only supports master mode, it has registers moved around, and it needs | |
323 | * some extra init to get it into I2C mode. The register moves are handled | |
324 | * by i2c_readl and i2c_writel | |
325 | */ | |
326 | static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev) | |
327 | { | |
328 | u32 val = 0; | |
329 | val = dvc_readl(i2c_dev, DVC_CTRL_REG3); | |
330 | val |= DVC_CTRL_REG3_SW_PROG; | |
331 | val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN; | |
332 | dvc_writel(i2c_dev, val, DVC_CTRL_REG3); | |
333 | ||
334 | val = dvc_readl(i2c_dev, DVC_CTRL_REG1); | |
335 | val |= DVC_CTRL_REG1_INTR_EN; | |
336 | dvc_writel(i2c_dev, val, DVC_CTRL_REG1); | |
337 | } | |
338 | ||
339 | static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) | |
340 | { | |
341 | u32 val; | |
342 | int err = 0; | |
343 | ||
344 | clk_enable(i2c_dev->clk); | |
345 | ||
346 | tegra_periph_reset_assert(i2c_dev->clk); | |
347 | udelay(2); | |
348 | tegra_periph_reset_deassert(i2c_dev->clk); | |
349 | ||
350 | if (i2c_dev->is_dvc) | |
351 | tegra_dvc_init(i2c_dev); | |
352 | ||
40abcf77 JC |
353 | val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN | |
354 | (0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT); | |
db811ca0 CC |
355 | i2c_writel(i2c_dev, val, I2C_CNFG); |
356 | i2c_writel(i2c_dev, 0, I2C_INT_MASK); | |
357 | clk_set_rate(i2c_dev->clk, i2c_dev->bus_clk_rate * 8); | |
358 | ||
65a1a0ac KW |
359 | if (!i2c_dev->is_dvc) { |
360 | u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG); | |
5afa9d35 SW |
361 | sl_cfg |= I2C_SL_CNFG_NACK | I2C_SL_CNFG_NEWSL; |
362 | i2c_writel(i2c_dev, sl_cfg, I2C_SL_CNFG); | |
363 | i2c_writel(i2c_dev, 0xfc, I2C_SL_ADDR1); | |
364 | i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2); | |
365 | ||
65a1a0ac KW |
366 | } |
367 | ||
db811ca0 CC |
368 | val = 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT | |
369 | 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT; | |
370 | i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); | |
371 | ||
372 | if (tegra_i2c_flush_fifos(i2c_dev)) | |
373 | err = -ETIMEDOUT; | |
374 | ||
375 | clk_disable(i2c_dev->clk); | |
cb63c62d TP |
376 | |
377 | if (i2c_dev->irq_disabled) { | |
378 | i2c_dev->irq_disabled = 0; | |
379 | enable_irq(i2c_dev->irq); | |
380 | } | |
381 | ||
db811ca0 CC |
382 | return err; |
383 | } | |
384 | ||
385 | static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) | |
386 | { | |
387 | u32 status; | |
388 | const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; | |
389 | struct tegra_i2c_dev *i2c_dev = dev_id; | |
390 | ||
391 | status = i2c_readl(i2c_dev, I2C_INT_STATUS); | |
392 | ||
393 | if (status == 0) { | |
cb63c62d TP |
394 | dev_warn(i2c_dev->dev, "irq status 0 %08x %08x %08x\n", |
395 | i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS), | |
396 | i2c_readl(i2c_dev, I2C_STATUS), | |
397 | i2c_readl(i2c_dev, I2C_CNFG)); | |
398 | i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; | |
399 | ||
400 | if (!i2c_dev->irq_disabled) { | |
401 | disable_irq_nosync(i2c_dev->irq); | |
402 | i2c_dev->irq_disabled = 1; | |
403 | } | |
404 | ||
405 | complete(&i2c_dev->msg_complete); | |
406 | goto err; | |
db811ca0 CC |
407 | } |
408 | ||
409 | if (unlikely(status & status_err)) { | |
410 | if (status & I2C_INT_NO_ACK) | |
411 | i2c_dev->msg_err |= I2C_ERR_NO_ACK; | |
412 | if (status & I2C_INT_ARBITRATION_LOST) | |
413 | i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST; | |
414 | complete(&i2c_dev->msg_complete); | |
415 | goto err; | |
416 | } | |
417 | ||
418 | if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) { | |
419 | if (i2c_dev->msg_buf_remaining) | |
420 | tegra_i2c_empty_rx_fifo(i2c_dev); | |
421 | else | |
422 | BUG(); | |
423 | } | |
424 | ||
425 | if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) { | |
426 | if (i2c_dev->msg_buf_remaining) | |
427 | tegra_i2c_fill_tx_fifo(i2c_dev); | |
428 | else | |
429 | tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ); | |
430 | } | |
431 | ||
96219c3a DA |
432 | if (status & I2C_INT_PACKET_XFER_COMPLETE) { |
433 | BUG_ON(i2c_dev->msg_buf_remaining); | |
db811ca0 | 434 | complete(&i2c_dev->msg_complete); |
96219c3a | 435 | } |
db811ca0 CC |
436 | |
437 | i2c_writel(i2c_dev, status, I2C_INT_STATUS); | |
438 | if (i2c_dev->is_dvc) | |
439 | dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); | |
440 | return IRQ_HANDLED; | |
441 | err: | |
25985edc | 442 | /* An error occurred, mask all interrupts */ |
db811ca0 CC |
443 | tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | |
444 | I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | | |
445 | I2C_INT_RX_FIFO_DATA_REQ); | |
446 | i2c_writel(i2c_dev, status, I2C_INT_STATUS); | |
cb63c62d TP |
447 | if (i2c_dev->is_dvc) |
448 | dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); | |
db811ca0 CC |
449 | return IRQ_HANDLED; |
450 | } | |
451 | ||
452 | static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, | |
453 | struct i2c_msg *msg, int stop) | |
454 | { | |
455 | u32 packet_header; | |
456 | u32 int_mask; | |
457 | int ret; | |
458 | ||
459 | tegra_i2c_flush_fifos(i2c_dev); | |
db811ca0 CC |
460 | |
461 | if (msg->len == 0) | |
462 | return -EINVAL; | |
463 | ||
464 | i2c_dev->msg_buf = msg->buf; | |
465 | i2c_dev->msg_buf_remaining = msg->len; | |
466 | i2c_dev->msg_err = I2C_ERR_NONE; | |
467 | i2c_dev->msg_read = (msg->flags & I2C_M_RD); | |
468 | INIT_COMPLETION(i2c_dev->msg_complete); | |
469 | ||
470 | packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) | | |
471 | PACKET_HEADER0_PROTOCOL_I2C | | |
472 | (i2c_dev->cont_id << PACKET_HEADER0_CONT_ID_SHIFT) | | |
473 | (1 << PACKET_HEADER0_PACKET_ID_SHIFT); | |
474 | i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); | |
475 | ||
476 | packet_header = msg->len - 1; | |
477 | i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); | |
478 | ||
479 | packet_header = msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT; | |
480 | packet_header |= I2C_HEADER_IE_ENABLE; | |
2078cf3b EG |
481 | if (!stop) |
482 | packet_header |= I2C_HEADER_REPEAT_START; | |
db811ca0 CC |
483 | if (msg->flags & I2C_M_TEN) |
484 | packet_header |= I2C_HEADER_10BIT_ADDR; | |
485 | if (msg->flags & I2C_M_IGNORE_NAK) | |
486 | packet_header |= I2C_HEADER_CONT_ON_NAK; | |
db811ca0 CC |
487 | if (msg->flags & I2C_M_RD) |
488 | packet_header |= I2C_HEADER_READ; | |
489 | i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); | |
490 | ||
491 | if (!(msg->flags & I2C_M_RD)) | |
492 | tegra_i2c_fill_tx_fifo(i2c_dev); | |
493 | ||
494 | int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; | |
495 | if (msg->flags & I2C_M_RD) | |
496 | int_mask |= I2C_INT_RX_FIFO_DATA_REQ; | |
497 | else if (i2c_dev->msg_buf_remaining) | |
498 | int_mask |= I2C_INT_TX_FIFO_DATA_REQ; | |
499 | tegra_i2c_unmask_irq(i2c_dev, int_mask); | |
500 | dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n", | |
501 | i2c_readl(i2c_dev, I2C_INT_MASK)); | |
502 | ||
503 | ret = wait_for_completion_timeout(&i2c_dev->msg_complete, TEGRA_I2C_TIMEOUT); | |
504 | tegra_i2c_mask_irq(i2c_dev, int_mask); | |
505 | ||
506 | if (WARN_ON(ret == 0)) { | |
507 | dev_err(i2c_dev->dev, "i2c transfer timed out\n"); | |
508 | ||
509 | tegra_i2c_init(i2c_dev); | |
510 | return -ETIMEDOUT; | |
511 | } | |
512 | ||
513 | dev_dbg(i2c_dev->dev, "transfer complete: %d %d %d\n", | |
514 | ret, completion_done(&i2c_dev->msg_complete), i2c_dev->msg_err); | |
515 | ||
516 | if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) | |
517 | return 0; | |
518 | ||
f70893d0 AC |
519 | /* |
520 | * NACK interrupt is generated before the I2C controller generates the | |
521 | * STOP condition on the bus. So wait for 2 clock periods before resetting | |
522 | * the controller so that STOP condition has been delivered properly. | |
523 | */ | |
524 | if (i2c_dev->msg_err == I2C_ERR_NO_ACK) | |
525 | udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate)); | |
526 | ||
db811ca0 CC |
527 | tegra_i2c_init(i2c_dev); |
528 | if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { | |
529 | if (msg->flags & I2C_M_IGNORE_NAK) | |
530 | return 0; | |
531 | return -EREMOTEIO; | |
532 | } | |
533 | ||
534 | return -EIO; | |
535 | } | |
536 | ||
537 | static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], | |
538 | int num) | |
539 | { | |
540 | struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); | |
541 | int i; | |
542 | int ret = 0; | |
543 | ||
544 | if (i2c_dev->is_suspended) | |
545 | return -EBUSY; | |
546 | ||
547 | clk_enable(i2c_dev->clk); | |
548 | for (i = 0; i < num; i++) { | |
549 | int stop = (i == (num - 1)) ? 1 : 0; | |
550 | ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], stop); | |
551 | if (ret) | |
552 | break; | |
553 | } | |
554 | clk_disable(i2c_dev->clk); | |
555 | return ret ?: i; | |
556 | } | |
557 | ||
558 | static u32 tegra_i2c_func(struct i2c_adapter *adap) | |
559 | { | |
048e29cf | 560 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
db811ca0 CC |
561 | } |
562 | ||
563 | static const struct i2c_algorithm tegra_i2c_algo = { | |
564 | .master_xfer = tegra_i2c_xfer, | |
565 | .functionality = tegra_i2c_func, | |
566 | }; | |
567 | ||
92891da1 | 568 | static int __devinit tegra_i2c_probe(struct platform_device *pdev) |
db811ca0 CC |
569 | { |
570 | struct tegra_i2c_dev *i2c_dev; | |
571 | struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data; | |
572 | struct resource *res; | |
573 | struct resource *iomem; | |
574 | struct clk *clk; | |
575 | struct clk *i2c_clk; | |
5c470f39 | 576 | const unsigned int *prop; |
f533c61e | 577 | void __iomem *base; |
db811ca0 CC |
578 | int irq; |
579 | int ret = 0; | |
580 | ||
581 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
582 | if (!res) { | |
583 | dev_err(&pdev->dev, "no mem resource\n"); | |
584 | return -EINVAL; | |
585 | } | |
586 | iomem = request_mem_region(res->start, resource_size(res), pdev->name); | |
587 | if (!iomem) { | |
588 | dev_err(&pdev->dev, "I2C region already claimed\n"); | |
589 | return -EBUSY; | |
590 | } | |
591 | ||
592 | base = ioremap(iomem->start, resource_size(iomem)); | |
593 | if (!base) { | |
594 | dev_err(&pdev->dev, "Cannot ioremap I2C region\n"); | |
595 | return -ENOMEM; | |
596 | } | |
597 | ||
598 | res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); | |
599 | if (!res) { | |
600 | dev_err(&pdev->dev, "no irq resource\n"); | |
601 | ret = -EINVAL; | |
602 | goto err_iounmap; | |
603 | } | |
604 | irq = res->start; | |
605 | ||
606 | clk = clk_get(&pdev->dev, NULL); | |
607 | if (IS_ERR(clk)) { | |
608 | dev_err(&pdev->dev, "missing controller clock"); | |
609 | ret = PTR_ERR(clk); | |
610 | goto err_release_region; | |
611 | } | |
612 | ||
613 | i2c_clk = clk_get(&pdev->dev, "i2c"); | |
614 | if (IS_ERR(i2c_clk)) { | |
615 | dev_err(&pdev->dev, "missing bus clock"); | |
616 | ret = PTR_ERR(i2c_clk); | |
617 | goto err_clk_put; | |
618 | } | |
619 | ||
620 | i2c_dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL); | |
621 | if (!i2c_dev) { | |
622 | ret = -ENOMEM; | |
623 | goto err_i2c_clk_put; | |
624 | } | |
625 | ||
626 | i2c_dev->base = base; | |
627 | i2c_dev->clk = clk; | |
628 | i2c_dev->i2c_clk = i2c_clk; | |
629 | i2c_dev->iomem = iomem; | |
630 | i2c_dev->adapter.algo = &tegra_i2c_algo; | |
631 | i2c_dev->irq = irq; | |
632 | i2c_dev->cont_id = pdev->id; | |
633 | i2c_dev->dev = &pdev->dev; | |
5c470f39 JB |
634 | |
635 | i2c_dev->bus_clk_rate = 100000; /* default clock rate */ | |
636 | if (pdata) { | |
637 | i2c_dev->bus_clk_rate = pdata->bus_clk_rate; | |
638 | ||
639 | } else if (i2c_dev->dev->of_node) { /* if there is a device tree node ... */ | |
640 | prop = of_get_property(i2c_dev->dev->of_node, | |
641 | "clock-frequency", NULL); | |
642 | if (prop) | |
643 | i2c_dev->bus_clk_rate = be32_to_cpup(prop); | |
644 | } | |
db811ca0 | 645 | |
68fb6695 SW |
646 | if (pdev->dev.of_node) |
647 | i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node, | |
648 | "nvidia,tegra20-i2c-dvc"); | |
649 | else if (pdev->id == 3) | |
db811ca0 CC |
650 | i2c_dev->is_dvc = 1; |
651 | init_completion(&i2c_dev->msg_complete); | |
652 | ||
653 | platform_set_drvdata(pdev, i2c_dev); | |
654 | ||
655 | ret = tegra_i2c_init(i2c_dev); | |
656 | if (ret) { | |
657 | dev_err(&pdev->dev, "Failed to initialize i2c controller"); | |
658 | goto err_free; | |
659 | } | |
660 | ||
661 | ret = request_irq(i2c_dev->irq, tegra_i2c_isr, 0, pdev->name, i2c_dev); | |
662 | if (ret) { | |
663 | dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); | |
664 | goto err_free; | |
665 | } | |
666 | ||
667 | clk_enable(i2c_dev->i2c_clk); | |
668 | ||
669 | i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); | |
670 | i2c_dev->adapter.owner = THIS_MODULE; | |
671 | i2c_dev->adapter.class = I2C_CLASS_HWMON; | |
672 | strlcpy(i2c_dev->adapter.name, "Tegra I2C adapter", | |
673 | sizeof(i2c_dev->adapter.name)); | |
674 | i2c_dev->adapter.algo = &tegra_i2c_algo; | |
675 | i2c_dev->adapter.dev.parent = &pdev->dev; | |
676 | i2c_dev->adapter.nr = pdev->id; | |
5c470f39 | 677 | i2c_dev->adapter.dev.of_node = pdev->dev.of_node; |
db811ca0 CC |
678 | |
679 | ret = i2c_add_numbered_adapter(&i2c_dev->adapter); | |
680 | if (ret) { | |
681 | dev_err(&pdev->dev, "Failed to add I2C adapter\n"); | |
682 | goto err_free_irq; | |
683 | } | |
684 | ||
5c470f39 JB |
685 | of_i2c_register_devices(&i2c_dev->adapter); |
686 | ||
db811ca0 CC |
687 | return 0; |
688 | err_free_irq: | |
689 | free_irq(i2c_dev->irq, i2c_dev); | |
690 | err_free: | |
691 | kfree(i2c_dev); | |
692 | err_i2c_clk_put: | |
693 | clk_put(i2c_clk); | |
694 | err_clk_put: | |
695 | clk_put(clk); | |
696 | err_release_region: | |
697 | release_mem_region(iomem->start, resource_size(iomem)); | |
698 | err_iounmap: | |
699 | iounmap(base); | |
700 | return ret; | |
701 | } | |
702 | ||
92891da1 | 703 | static int __devexit tegra_i2c_remove(struct platform_device *pdev) |
db811ca0 CC |
704 | { |
705 | struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | |
706 | i2c_del_adapter(&i2c_dev->adapter); | |
707 | free_irq(i2c_dev->irq, i2c_dev); | |
708 | clk_put(i2c_dev->i2c_clk); | |
709 | clk_put(i2c_dev->clk); | |
710 | release_mem_region(i2c_dev->iomem->start, | |
711 | resource_size(i2c_dev->iomem)); | |
712 | iounmap(i2c_dev->base); | |
713 | kfree(i2c_dev); | |
714 | return 0; | |
715 | } | |
716 | ||
717 | #ifdef CONFIG_PM | |
718 | static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state) | |
719 | { | |
720 | struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | |
721 | ||
722 | i2c_lock_adapter(&i2c_dev->adapter); | |
723 | i2c_dev->is_suspended = true; | |
724 | i2c_unlock_adapter(&i2c_dev->adapter); | |
725 | ||
726 | return 0; | |
727 | } | |
728 | ||
729 | static int tegra_i2c_resume(struct platform_device *pdev) | |
730 | { | |
731 | struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | |
732 | int ret; | |
733 | ||
734 | i2c_lock_adapter(&i2c_dev->adapter); | |
735 | ||
736 | ret = tegra_i2c_init(i2c_dev); | |
737 | ||
738 | if (ret) { | |
739 | i2c_unlock_adapter(&i2c_dev->adapter); | |
740 | return ret; | |
741 | } | |
742 | ||
743 | i2c_dev->is_suspended = false; | |
744 | ||
745 | i2c_unlock_adapter(&i2c_dev->adapter); | |
746 | ||
747 | return 0; | |
748 | } | |
749 | #endif | |
750 | ||
406bd18a JB |
751 | #if defined(CONFIG_OF) |
752 | /* Match table for of_platform binding */ | |
753 | static const struct of_device_id tegra_i2c_of_match[] __devinitconst = { | |
754 | { .compatible = "nvidia,tegra20-i2c", }, | |
68fb6695 | 755 | { .compatible = "nvidia,tegra20-i2c-dvc", }, |
406bd18a JB |
756 | {}, |
757 | }; | |
758 | MODULE_DEVICE_TABLE(of, tegra_i2c_of_match); | |
759 | #else | |
760 | #define tegra_i2c_of_match NULL | |
761 | #endif | |
762 | ||
db811ca0 CC |
763 | static struct platform_driver tegra_i2c_driver = { |
764 | .probe = tegra_i2c_probe, | |
218d06d7 | 765 | .remove = __devexit_p(tegra_i2c_remove), |
db811ca0 CC |
766 | #ifdef CONFIG_PM |
767 | .suspend = tegra_i2c_suspend, | |
768 | .resume = tegra_i2c_resume, | |
769 | #endif | |
770 | .driver = { | |
771 | .name = "tegra-i2c", | |
772 | .owner = THIS_MODULE, | |
406bd18a | 773 | .of_match_table = tegra_i2c_of_match, |
db811ca0 CC |
774 | }, |
775 | }; | |
776 | ||
777 | static int __init tegra_i2c_init_driver(void) | |
778 | { | |
779 | return platform_driver_register(&tegra_i2c_driver); | |
780 | } | |
781 | ||
782 | static void __exit tegra_i2c_exit_driver(void) | |
783 | { | |
784 | platform_driver_unregister(&tegra_i2c_driver); | |
785 | } | |
786 | ||
787 | subsys_initcall(tegra_i2c_init_driver); | |
788 | module_exit(tegra_i2c_exit_driver); | |
789 | ||
790 | MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver"); | |
791 | MODULE_AUTHOR("Colin Cross"); | |
792 | MODULE_LICENSE("GPL v2"); |