diff options
author | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
---|---|---|
committer | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
commit | c71c03bda1e86c9d5198c5d83f712e695c4f2a1e (patch) | |
tree | ecb166cb3e2b7e2adb3b5e292245fefd23381ac8 /drivers/i2c/busses/i2c-tegra.c | |
parent | ea53c912f8a86a8567697115b6a0d8152beee5c8 (diff) | |
parent | 6a00f206debf8a5c8899055726ad127dbeeed098 (diff) |
Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp
Conflicts:
litmus/sched_cedf.c
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 735 |
1 files changed, 735 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c new file mode 100644 index 000000000000..fb3b4f8f8152 --- /dev/null +++ b/drivers/i2c/busses/i2c-tegra.c | |||
@@ -0,0 +1,735 @@ | |||
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> | ||
29 | |||
30 | #include <asm/unaligned.h> | ||
31 | |||
32 | #include <mach/clk.h> | ||
33 | |||
34 | #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000)) | ||
35 | #define BYTES_PER_FIFO_WORD 4 | ||
36 | |||
37 | #define I2C_CNFG 0x000 | ||
38 | #define I2C_CNFG_DEBOUNCE_CNT_SHIFT 12 | ||
39 | #define I2C_CNFG_PACKET_MODE_EN (1<<10) | ||
40 | #define I2C_CNFG_NEW_MASTER_FSM (1<<11) | ||
41 | #define I2C_STATUS 0x01C | ||
42 | #define I2C_SL_CNFG 0x020 | ||
43 | #define I2C_SL_CNFG_NACK (1<<1) | ||
44 | #define I2C_SL_CNFG_NEWSL (1<<2) | ||
45 | #define I2C_SL_ADDR1 0x02c | ||
46 | #define I2C_SL_ADDR2 0x030 | ||
47 | #define I2C_TX_FIFO 0x050 | ||
48 | #define I2C_RX_FIFO 0x054 | ||
49 | #define I2C_PACKET_TRANSFER_STATUS 0x058 | ||
50 | #define I2C_FIFO_CONTROL 0x05c | ||
51 | #define I2C_FIFO_CONTROL_TX_FLUSH (1<<1) | ||
52 | #define I2C_FIFO_CONTROL_RX_FLUSH (1<<0) | ||
53 | #define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5 | ||
54 | #define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2 | ||
55 | #define I2C_FIFO_STATUS 0x060 | ||
56 | #define I2C_FIFO_STATUS_TX_MASK 0xF0 | ||
57 | #define I2C_FIFO_STATUS_TX_SHIFT 4 | ||
58 | #define I2C_FIFO_STATUS_RX_MASK 0x0F | ||
59 | #define I2C_FIFO_STATUS_RX_SHIFT 0 | ||
60 | #define I2C_INT_MASK 0x064 | ||
61 | #define I2C_INT_STATUS 0x068 | ||
62 | #define I2C_INT_PACKET_XFER_COMPLETE (1<<7) | ||
63 | #define I2C_INT_ALL_PACKETS_XFER_COMPLETE (1<<6) | ||
64 | #define I2C_INT_TX_FIFO_OVERFLOW (1<<5) | ||
65 | #define I2C_INT_RX_FIFO_UNDERFLOW (1<<4) | ||
66 | #define I2C_INT_NO_ACK (1<<3) | ||
67 | #define I2C_INT_ARBITRATION_LOST (1<<2) | ||
68 | #define I2C_INT_TX_FIFO_DATA_REQ (1<<1) | ||
69 | #define I2C_INT_RX_FIFO_DATA_REQ (1<<0) | ||
70 | #define I2C_CLK_DIVISOR 0x06c | ||
71 | |||
72 | #define DVC_CTRL_REG1 0x000 | ||
73 | #define DVC_CTRL_REG1_INTR_EN (1<<10) | ||
74 | #define DVC_CTRL_REG2 0x004 | ||
75 | #define DVC_CTRL_REG3 0x008 | ||
76 | #define DVC_CTRL_REG3_SW_PROG (1<<26) | ||
77 | #define DVC_CTRL_REG3_I2C_DONE_INTR_EN (1<<30) | ||
78 | #define DVC_STATUS 0x00c | ||
79 | #define DVC_STATUS_I2C_DONE_INTR (1<<30) | ||
80 | |||
81 | #define I2C_ERR_NONE 0x00 | ||
82 | #define I2C_ERR_NO_ACK 0x01 | ||
83 | #define I2C_ERR_ARBITRATION_LOST 0x02 | ||
84 | #define I2C_ERR_UNKNOWN_INTERRUPT 0x04 | ||
85 | |||
86 | #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28 | ||
87 | #define PACKET_HEADER0_PACKET_ID_SHIFT 16 | ||
88 | #define PACKET_HEADER0_CONT_ID_SHIFT 12 | ||
89 | #define PACKET_HEADER0_PROTOCOL_I2C (1<<4) | ||
90 | |||
91 | #define I2C_HEADER_HIGHSPEED_MODE (1<<22) | ||
92 | #define I2C_HEADER_CONT_ON_NAK (1<<21) | ||
93 | #define I2C_HEADER_SEND_START_BYTE (1<<20) | ||
94 | #define I2C_HEADER_READ (1<<19) | ||
95 | #define I2C_HEADER_10BIT_ADDR (1<<18) | ||
96 | #define I2C_HEADER_IE_ENABLE (1<<17) | ||
97 | #define I2C_HEADER_REPEAT_START (1<<16) | ||
98 | #define I2C_HEADER_MASTER_ADDR_SHIFT 12 | ||
99 | #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 | ||
100 | |||
101 | /** | ||
102 | * struct tegra_i2c_dev - per device i2c context | ||
103 | * @dev: device reference for power management | ||
104 | * @adapter: core i2c layer adapter information | ||
105 | * @clk: clock reference for i2c controller | ||
106 | * @i2c_clk: clock reference for i2c bus | ||
107 | * @iomem: memory resource for registers | ||
108 | * @base: ioremapped registers cookie | ||
109 | * @cont_id: i2c controller id, used for for packet header | ||
110 | * @irq: irq number of transfer complete interrupt | ||
111 | * @is_dvc: identifies the DVC i2c controller, has a different register layout | ||
112 | * @msg_complete: transfer completion notifier | ||
113 | * @msg_err: error code for completed message | ||
114 | * @msg_buf: pointer to current message data | ||
115 | * @msg_buf_remaining: size of unsent data in the message buffer | ||
116 | * @msg_read: identifies read transfers | ||
117 | * @bus_clk_rate: current i2c bus clock rate | ||
118 | * @is_suspended: prevents i2c controller accesses after suspend is called | ||
119 | */ | ||
120 | struct tegra_i2c_dev { | ||
121 | struct device *dev; | ||
122 | struct i2c_adapter adapter; | ||
123 | struct clk *clk; | ||
124 | struct clk *i2c_clk; | ||
125 | struct resource *iomem; | ||
126 | void __iomem *base; | ||
127 | int cont_id; | ||
128 | int irq; | ||
129 | bool irq_disabled; | ||
130 | int is_dvc; | ||
131 | struct completion msg_complete; | ||
132 | int msg_err; | ||
133 | u8 *msg_buf; | ||
134 | size_t msg_buf_remaining; | ||
135 | int msg_read; | ||
136 | unsigned long bus_clk_rate; | ||
137 | bool is_suspended; | ||
138 | }; | ||
139 | |||
140 | static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned long reg) | ||
141 | { | ||
142 | writel(val, i2c_dev->base + reg); | ||
143 | } | ||
144 | |||
145 | static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) | ||
146 | { | ||
147 | return readl(i2c_dev->base + reg); | ||
148 | } | ||
149 | |||
150 | /* | ||
151 | * i2c_writel and i2c_readl will offset the register if necessary to talk | ||
152 | * to the I2C block inside the DVC block | ||
153 | */ | ||
154 | static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, | ||
155 | unsigned long reg) | ||
156 | { | ||
157 | if (i2c_dev->is_dvc) | ||
158 | reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40; | ||
159 | return reg; | ||
160 | } | ||
161 | |||
162 | static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, | ||
163 | unsigned long reg) | ||
164 | { | ||
165 | writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); | ||
166 | } | ||
167 | |||
168 | static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg) | ||
169 | { | ||
170 | return readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); | ||
171 | } | ||
172 | |||
173 | static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, | ||
174 | unsigned long reg, int len) | ||
175 | { | ||
176 | writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); | ||
177 | } | ||
178 | |||
179 | static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, | ||
180 | unsigned long reg, int len) | ||
181 | { | ||
182 | readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); | ||
183 | } | ||
184 | |||
185 | static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) | ||
186 | { | ||
187 | u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK); | ||
188 | int_mask &= ~mask; | ||
189 | i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); | ||
190 | } | ||
191 | |||
192 | static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) | ||
193 | { | ||
194 | u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK); | ||
195 | int_mask |= mask; | ||
196 | i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); | ||
197 | } | ||
198 | |||
199 | static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) | ||
200 | { | ||
201 | unsigned long timeout = jiffies + HZ; | ||
202 | u32 val = i2c_readl(i2c_dev, I2C_FIFO_CONTROL); | ||
203 | val |= I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH; | ||
204 | i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); | ||
205 | |||
206 | while (i2c_readl(i2c_dev, I2C_FIFO_CONTROL) & | ||
207 | (I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH)) { | ||
208 | if (time_after(jiffies, timeout)) { | ||
209 | dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n"); | ||
210 | return -ETIMEDOUT; | ||
211 | } | ||
212 | msleep(1); | ||
213 | } | ||
214 | return 0; | ||
215 | } | ||
216 | |||
217 | static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) | ||
218 | { | ||
219 | u32 val; | ||
220 | int rx_fifo_avail; | ||
221 | u8 *buf = i2c_dev->msg_buf; | ||
222 | size_t buf_remaining = i2c_dev->msg_buf_remaining; | ||
223 | int words_to_transfer; | ||
224 | |||
225 | val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); | ||
226 | rx_fifo_avail = (val & I2C_FIFO_STATUS_RX_MASK) >> | ||
227 | I2C_FIFO_STATUS_RX_SHIFT; | ||
228 | |||
229 | /* Rounds down to not include partial word at the end of buf */ | ||
230 | words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; | ||
231 | if (words_to_transfer > rx_fifo_avail) | ||
232 | words_to_transfer = rx_fifo_avail; | ||
233 | |||
234 | i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer); | ||
235 | |||
236 | buf += words_to_transfer * BYTES_PER_FIFO_WORD; | ||
237 | buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; | ||
238 | rx_fifo_avail -= words_to_transfer; | ||
239 | |||
240 | /* | ||
241 | * If there is a partial word at the end of buf, handle it manually to | ||
242 | * prevent overwriting past the end of buf | ||
243 | */ | ||
244 | if (rx_fifo_avail > 0 && buf_remaining > 0) { | ||
245 | BUG_ON(buf_remaining > 3); | ||
246 | val = i2c_readl(i2c_dev, I2C_RX_FIFO); | ||
247 | memcpy(buf, &val, buf_remaining); | ||
248 | buf_remaining = 0; | ||
249 | rx_fifo_avail--; | ||
250 | } | ||
251 | |||
252 | BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0); | ||
253 | i2c_dev->msg_buf_remaining = buf_remaining; | ||
254 | i2c_dev->msg_buf = buf; | ||
255 | return 0; | ||
256 | } | ||
257 | |||
258 | static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) | ||
259 | { | ||
260 | u32 val; | ||
261 | int tx_fifo_avail; | ||
262 | u8 *buf = i2c_dev->msg_buf; | ||
263 | size_t buf_remaining = i2c_dev->msg_buf_remaining; | ||
264 | int words_to_transfer; | ||
265 | |||
266 | val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); | ||
267 | tx_fifo_avail = (val & I2C_FIFO_STATUS_TX_MASK) >> | ||
268 | I2C_FIFO_STATUS_TX_SHIFT; | ||
269 | |||
270 | /* Rounds down to not include partial word at the end of buf */ | ||
271 | words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; | ||
272 | if (words_to_transfer > tx_fifo_avail) | ||
273 | words_to_transfer = tx_fifo_avail; | ||
274 | |||
275 | i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); | ||
276 | |||
277 | buf += words_to_transfer * BYTES_PER_FIFO_WORD; | ||
278 | buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; | ||
279 | tx_fifo_avail -= words_to_transfer; | ||
280 | |||
281 | /* | ||
282 | * If there is a partial word at the end of buf, handle it manually to | ||
283 | * prevent reading past the end of buf, which could cross a page | ||
284 | * boundary and fault. | ||
285 | */ | ||
286 | if (tx_fifo_avail > 0 && buf_remaining > 0) { | ||
287 | BUG_ON(buf_remaining > 3); | ||
288 | memcpy(&val, buf, buf_remaining); | ||
289 | i2c_writel(i2c_dev, val, I2C_TX_FIFO); | ||
290 | buf_remaining = 0; | ||
291 | tx_fifo_avail--; | ||
292 | } | ||
293 | |||
294 | BUG_ON(tx_fifo_avail > 0 && buf_remaining > 0); | ||
295 | i2c_dev->msg_buf_remaining = buf_remaining; | ||
296 | i2c_dev->msg_buf = buf; | ||
297 | return 0; | ||
298 | } | ||
299 | |||
300 | /* | ||
301 | * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller) | ||
302 | * block. This block is identical to the rest of the I2C blocks, except that | ||
303 | * it only supports master mode, it has registers moved around, and it needs | ||
304 | * some extra init to get it into I2C mode. The register moves are handled | ||
305 | * by i2c_readl and i2c_writel | ||
306 | */ | ||
307 | static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev) | ||
308 | { | ||
309 | u32 val = 0; | ||
310 | val = dvc_readl(i2c_dev, DVC_CTRL_REG3); | ||
311 | val |= DVC_CTRL_REG3_SW_PROG; | ||
312 | val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN; | ||
313 | dvc_writel(i2c_dev, val, DVC_CTRL_REG3); | ||
314 | |||
315 | val = dvc_readl(i2c_dev, DVC_CTRL_REG1); | ||
316 | val |= DVC_CTRL_REG1_INTR_EN; | ||
317 | dvc_writel(i2c_dev, val, DVC_CTRL_REG1); | ||
318 | } | ||
319 | |||
320 | static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) | ||
321 | { | ||
322 | u32 val; | ||
323 | int err = 0; | ||
324 | |||
325 | clk_enable(i2c_dev->clk); | ||
326 | |||
327 | tegra_periph_reset_assert(i2c_dev->clk); | ||
328 | udelay(2); | ||
329 | tegra_periph_reset_deassert(i2c_dev->clk); | ||
330 | |||
331 | if (i2c_dev->is_dvc) | ||
332 | tegra_dvc_init(i2c_dev); | ||
333 | |||
334 | val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN | | ||
335 | (0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT); | ||
336 | i2c_writel(i2c_dev, val, I2C_CNFG); | ||
337 | i2c_writel(i2c_dev, 0, I2C_INT_MASK); | ||
338 | clk_set_rate(i2c_dev->clk, i2c_dev->bus_clk_rate * 8); | ||
339 | |||
340 | if (!i2c_dev->is_dvc) { | ||
341 | u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG); | ||
342 | sl_cfg |= I2C_SL_CNFG_NACK | I2C_SL_CNFG_NEWSL; | ||
343 | i2c_writel(i2c_dev, sl_cfg, I2C_SL_CNFG); | ||
344 | i2c_writel(i2c_dev, 0xfc, I2C_SL_ADDR1); | ||
345 | i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2); | ||
346 | |||
347 | } | ||
348 | |||
349 | val = 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT | | ||
350 | 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT; | ||
351 | i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL); | ||
352 | |||
353 | if (tegra_i2c_flush_fifos(i2c_dev)) | ||
354 | err = -ETIMEDOUT; | ||
355 | |||
356 | clk_disable(i2c_dev->clk); | ||
357 | |||
358 | if (i2c_dev->irq_disabled) { | ||
359 | i2c_dev->irq_disabled = 0; | ||
360 | enable_irq(i2c_dev->irq); | ||
361 | } | ||
362 | |||
363 | return err; | ||
364 | } | ||
365 | |||
366 | static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) | ||
367 | { | ||
368 | u32 status; | ||
369 | const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; | ||
370 | struct tegra_i2c_dev *i2c_dev = dev_id; | ||
371 | |||
372 | status = i2c_readl(i2c_dev, I2C_INT_STATUS); | ||
373 | |||
374 | if (status == 0) { | ||
375 | dev_warn(i2c_dev->dev, "irq status 0 %08x %08x %08x\n", | ||
376 | i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS), | ||
377 | i2c_readl(i2c_dev, I2C_STATUS), | ||
378 | i2c_readl(i2c_dev, I2C_CNFG)); | ||
379 | i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; | ||
380 | |||
381 | if (!i2c_dev->irq_disabled) { | ||
382 | disable_irq_nosync(i2c_dev->irq); | ||
383 | i2c_dev->irq_disabled = 1; | ||
384 | } | ||
385 | |||
386 | complete(&i2c_dev->msg_complete); | ||
387 | goto err; | ||
388 | } | ||
389 | |||
390 | if (unlikely(status & status_err)) { | ||
391 | if (status & I2C_INT_NO_ACK) | ||
392 | i2c_dev->msg_err |= I2C_ERR_NO_ACK; | ||
393 | if (status & I2C_INT_ARBITRATION_LOST) | ||
394 | i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST; | ||
395 | complete(&i2c_dev->msg_complete); | ||
396 | goto err; | ||
397 | } | ||
398 | |||
399 | if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) { | ||
400 | if (i2c_dev->msg_buf_remaining) | ||
401 | tegra_i2c_empty_rx_fifo(i2c_dev); | ||
402 | else | ||
403 | BUG(); | ||
404 | } | ||
405 | |||
406 | if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) { | ||
407 | if (i2c_dev->msg_buf_remaining) | ||
408 | tegra_i2c_fill_tx_fifo(i2c_dev); | ||
409 | else | ||
410 | tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ); | ||
411 | } | ||
412 | |||
413 | if ((status & I2C_INT_PACKET_XFER_COMPLETE) && | ||
414 | !i2c_dev->msg_buf_remaining) | ||
415 | complete(&i2c_dev->msg_complete); | ||
416 | |||
417 | i2c_writel(i2c_dev, status, I2C_INT_STATUS); | ||
418 | if (i2c_dev->is_dvc) | ||
419 | dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); | ||
420 | return IRQ_HANDLED; | ||
421 | err: | ||
422 | /* An error occurred, mask all interrupts */ | ||
423 | tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | | ||
424 | I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ | | ||
425 | I2C_INT_RX_FIFO_DATA_REQ); | ||
426 | i2c_writel(i2c_dev, status, I2C_INT_STATUS); | ||
427 | if (i2c_dev->is_dvc) | ||
428 | dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); | ||
429 | return IRQ_HANDLED; | ||
430 | } | ||
431 | |||
432 | static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, | ||
433 | struct i2c_msg *msg, int stop) | ||
434 | { | ||
435 | u32 packet_header; | ||
436 | u32 int_mask; | ||
437 | int ret; | ||
438 | |||
439 | tegra_i2c_flush_fifos(i2c_dev); | ||
440 | i2c_writel(i2c_dev, 0xFF, I2C_INT_STATUS); | ||
441 | |||
442 | if (msg->len == 0) | ||
443 | return -EINVAL; | ||
444 | |||
445 | i2c_dev->msg_buf = msg->buf; | ||
446 | i2c_dev->msg_buf_remaining = msg->len; | ||
447 | i2c_dev->msg_err = I2C_ERR_NONE; | ||
448 | i2c_dev->msg_read = (msg->flags & I2C_M_RD); | ||
449 | INIT_COMPLETION(i2c_dev->msg_complete); | ||
450 | |||
451 | packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) | | ||
452 | PACKET_HEADER0_PROTOCOL_I2C | | ||
453 | (i2c_dev->cont_id << PACKET_HEADER0_CONT_ID_SHIFT) | | ||
454 | (1 << PACKET_HEADER0_PACKET_ID_SHIFT); | ||
455 | i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); | ||
456 | |||
457 | packet_header = msg->len - 1; | ||
458 | i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); | ||
459 | |||
460 | packet_header = msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT; | ||
461 | packet_header |= I2C_HEADER_IE_ENABLE; | ||
462 | if (!stop) | ||
463 | packet_header |= I2C_HEADER_REPEAT_START; | ||
464 | if (msg->flags & I2C_M_TEN) | ||
465 | packet_header |= I2C_HEADER_10BIT_ADDR; | ||
466 | if (msg->flags & I2C_M_IGNORE_NAK) | ||
467 | packet_header |= I2C_HEADER_CONT_ON_NAK; | ||
468 | if (msg->flags & I2C_M_RD) | ||
469 | packet_header |= I2C_HEADER_READ; | ||
470 | i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); | ||
471 | |||
472 | if (!(msg->flags & I2C_M_RD)) | ||
473 | tegra_i2c_fill_tx_fifo(i2c_dev); | ||
474 | |||
475 | int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; | ||
476 | if (msg->flags & I2C_M_RD) | ||
477 | int_mask |= I2C_INT_RX_FIFO_DATA_REQ; | ||
478 | else if (i2c_dev->msg_buf_remaining) | ||
479 | int_mask |= I2C_INT_TX_FIFO_DATA_REQ; | ||
480 | tegra_i2c_unmask_irq(i2c_dev, int_mask); | ||
481 | dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n", | ||
482 | i2c_readl(i2c_dev, I2C_INT_MASK)); | ||
483 | |||
484 | ret = wait_for_completion_timeout(&i2c_dev->msg_complete, TEGRA_I2C_TIMEOUT); | ||
485 | tegra_i2c_mask_irq(i2c_dev, int_mask); | ||
486 | |||
487 | if (WARN_ON(ret == 0)) { | ||
488 | dev_err(i2c_dev->dev, "i2c transfer timed out\n"); | ||
489 | |||
490 | tegra_i2c_init(i2c_dev); | ||
491 | return -ETIMEDOUT; | ||
492 | } | ||
493 | |||
494 | dev_dbg(i2c_dev->dev, "transfer complete: %d %d %d\n", | ||
495 | ret, completion_done(&i2c_dev->msg_complete), i2c_dev->msg_err); | ||
496 | |||
497 | if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) | ||
498 | return 0; | ||
499 | |||
500 | tegra_i2c_init(i2c_dev); | ||
501 | if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { | ||
502 | if (msg->flags & I2C_M_IGNORE_NAK) | ||
503 | return 0; | ||
504 | return -EREMOTEIO; | ||
505 | } | ||
506 | |||
507 | return -EIO; | ||
508 | } | ||
509 | |||
510 | static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], | ||
511 | int num) | ||
512 | { | ||
513 | struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); | ||
514 | int i; | ||
515 | int ret = 0; | ||
516 | |||
517 | if (i2c_dev->is_suspended) | ||
518 | return -EBUSY; | ||
519 | |||
520 | clk_enable(i2c_dev->clk); | ||
521 | for (i = 0; i < num; i++) { | ||
522 | int stop = (i == (num - 1)) ? 1 : 0; | ||
523 | ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], stop); | ||
524 | if (ret) | ||
525 | break; | ||
526 | } | ||
527 | clk_disable(i2c_dev->clk); | ||
528 | return ret ?: i; | ||
529 | } | ||
530 | |||
531 | static u32 tegra_i2c_func(struct i2c_adapter *adap) | ||
532 | { | ||
533 | return I2C_FUNC_I2C; | ||
534 | } | ||
535 | |||
536 | static const struct i2c_algorithm tegra_i2c_algo = { | ||
537 | .master_xfer = tegra_i2c_xfer, | ||
538 | .functionality = tegra_i2c_func, | ||
539 | }; | ||
540 | |||
541 | static int tegra_i2c_probe(struct platform_device *pdev) | ||
542 | { | ||
543 | struct tegra_i2c_dev *i2c_dev; | ||
544 | struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data; | ||
545 | struct resource *res; | ||
546 | struct resource *iomem; | ||
547 | struct clk *clk; | ||
548 | struct clk *i2c_clk; | ||
549 | void *base; | ||
550 | int irq; | ||
551 | int ret = 0; | ||
552 | |||
553 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
554 | if (!res) { | ||
555 | dev_err(&pdev->dev, "no mem resource\n"); | ||
556 | return -EINVAL; | ||
557 | } | ||
558 | iomem = request_mem_region(res->start, resource_size(res), pdev->name); | ||
559 | if (!iomem) { | ||
560 | dev_err(&pdev->dev, "I2C region already claimed\n"); | ||
561 | return -EBUSY; | ||
562 | } | ||
563 | |||
564 | base = ioremap(iomem->start, resource_size(iomem)); | ||
565 | if (!base) { | ||
566 | dev_err(&pdev->dev, "Cannot ioremap I2C region\n"); | ||
567 | return -ENOMEM; | ||
568 | } | ||
569 | |||
570 | res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); | ||
571 | if (!res) { | ||
572 | dev_err(&pdev->dev, "no irq resource\n"); | ||
573 | ret = -EINVAL; | ||
574 | goto err_iounmap; | ||
575 | } | ||
576 | irq = res->start; | ||
577 | |||
578 | clk = clk_get(&pdev->dev, NULL); | ||
579 | if (IS_ERR(clk)) { | ||
580 | dev_err(&pdev->dev, "missing controller clock"); | ||
581 | ret = PTR_ERR(clk); | ||
582 | goto err_release_region; | ||
583 | } | ||
584 | |||
585 | i2c_clk = clk_get(&pdev->dev, "i2c"); | ||
586 | if (IS_ERR(i2c_clk)) { | ||
587 | dev_err(&pdev->dev, "missing bus clock"); | ||
588 | ret = PTR_ERR(i2c_clk); | ||
589 | goto err_clk_put; | ||
590 | } | ||
591 | |||
592 | i2c_dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL); | ||
593 | if (!i2c_dev) { | ||
594 | ret = -ENOMEM; | ||
595 | goto err_i2c_clk_put; | ||
596 | } | ||
597 | |||
598 | i2c_dev->base = base; | ||
599 | i2c_dev->clk = clk; | ||
600 | i2c_dev->i2c_clk = i2c_clk; | ||
601 | i2c_dev->iomem = iomem; | ||
602 | i2c_dev->adapter.algo = &tegra_i2c_algo; | ||
603 | i2c_dev->irq = irq; | ||
604 | i2c_dev->cont_id = pdev->id; | ||
605 | i2c_dev->dev = &pdev->dev; | ||
606 | i2c_dev->bus_clk_rate = pdata ? pdata->bus_clk_rate : 100000; | ||
607 | |||
608 | if (pdev->id == 3) | ||
609 | i2c_dev->is_dvc = 1; | ||
610 | init_completion(&i2c_dev->msg_complete); | ||
611 | |||
612 | platform_set_drvdata(pdev, i2c_dev); | ||
613 | |||
614 | ret = tegra_i2c_init(i2c_dev); | ||
615 | if (ret) { | ||
616 | dev_err(&pdev->dev, "Failed to initialize i2c controller"); | ||
617 | goto err_free; | ||
618 | } | ||
619 | |||
620 | ret = request_irq(i2c_dev->irq, tegra_i2c_isr, 0, pdev->name, i2c_dev); | ||
621 | if (ret) { | ||
622 | dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); | ||
623 | goto err_free; | ||
624 | } | ||
625 | |||
626 | clk_enable(i2c_dev->i2c_clk); | ||
627 | |||
628 | i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); | ||
629 | i2c_dev->adapter.owner = THIS_MODULE; | ||
630 | i2c_dev->adapter.class = I2C_CLASS_HWMON; | ||
631 | strlcpy(i2c_dev->adapter.name, "Tegra I2C adapter", | ||
632 | sizeof(i2c_dev->adapter.name)); | ||
633 | i2c_dev->adapter.algo = &tegra_i2c_algo; | ||
634 | i2c_dev->adapter.dev.parent = &pdev->dev; | ||
635 | i2c_dev->adapter.nr = pdev->id; | ||
636 | |||
637 | ret = i2c_add_numbered_adapter(&i2c_dev->adapter); | ||
638 | if (ret) { | ||
639 | dev_err(&pdev->dev, "Failed to add I2C adapter\n"); | ||
640 | goto err_free_irq; | ||
641 | } | ||
642 | |||
643 | return 0; | ||
644 | err_free_irq: | ||
645 | free_irq(i2c_dev->irq, i2c_dev); | ||
646 | err_free: | ||
647 | kfree(i2c_dev); | ||
648 | err_i2c_clk_put: | ||
649 | clk_put(i2c_clk); | ||
650 | err_clk_put: | ||
651 | clk_put(clk); | ||
652 | err_release_region: | ||
653 | release_mem_region(iomem->start, resource_size(iomem)); | ||
654 | err_iounmap: | ||
655 | iounmap(base); | ||
656 | return ret; | ||
657 | } | ||
658 | |||
659 | static int tegra_i2c_remove(struct platform_device *pdev) | ||
660 | { | ||
661 | struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | ||
662 | i2c_del_adapter(&i2c_dev->adapter); | ||
663 | free_irq(i2c_dev->irq, i2c_dev); | ||
664 | clk_put(i2c_dev->i2c_clk); | ||
665 | clk_put(i2c_dev->clk); | ||
666 | release_mem_region(i2c_dev->iomem->start, | ||
667 | resource_size(i2c_dev->iomem)); | ||
668 | iounmap(i2c_dev->base); | ||
669 | kfree(i2c_dev); | ||
670 | return 0; | ||
671 | } | ||
672 | |||
673 | #ifdef CONFIG_PM | ||
674 | static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state) | ||
675 | { | ||
676 | struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | ||
677 | |||
678 | i2c_lock_adapter(&i2c_dev->adapter); | ||
679 | i2c_dev->is_suspended = true; | ||
680 | i2c_unlock_adapter(&i2c_dev->adapter); | ||
681 | |||
682 | return 0; | ||
683 | } | ||
684 | |||
685 | static int tegra_i2c_resume(struct platform_device *pdev) | ||
686 | { | ||
687 | struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); | ||
688 | int ret; | ||
689 | |||
690 | i2c_lock_adapter(&i2c_dev->adapter); | ||
691 | |||
692 | ret = tegra_i2c_init(i2c_dev); | ||
693 | |||
694 | if (ret) { | ||
695 | i2c_unlock_adapter(&i2c_dev->adapter); | ||
696 | return ret; | ||
697 | } | ||
698 | |||
699 | i2c_dev->is_suspended = false; | ||
700 | |||
701 | i2c_unlock_adapter(&i2c_dev->adapter); | ||
702 | |||
703 | return 0; | ||
704 | } | ||
705 | #endif | ||
706 | |||
707 | static struct platform_driver tegra_i2c_driver = { | ||
708 | .probe = tegra_i2c_probe, | ||
709 | .remove = tegra_i2c_remove, | ||
710 | #ifdef CONFIG_PM | ||
711 | .suspend = tegra_i2c_suspend, | ||
712 | .resume = tegra_i2c_resume, | ||
713 | #endif | ||
714 | .driver = { | ||
715 | .name = "tegra-i2c", | ||
716 | .owner = THIS_MODULE, | ||
717 | }, | ||
718 | }; | ||
719 | |||
720 | static int __init tegra_i2c_init_driver(void) | ||
721 | { | ||
722 | return platform_driver_register(&tegra_i2c_driver); | ||
723 | } | ||
724 | |||
725 | static void __exit tegra_i2c_exit_driver(void) | ||
726 | { | ||
727 | platform_driver_unregister(&tegra_i2c_driver); | ||
728 | } | ||
729 | |||
730 | subsys_initcall(tegra_i2c_init_driver); | ||
731 | module_exit(tegra_i2c_exit_driver); | ||
732 | |||
733 | MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver"); | ||
734 | MODULE_AUTHOR("Colin Cross"); | ||
735 | MODULE_LICENSE("GPL v2"); | ||