1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2002 Motorola GSG-China
4 *
5 * Author:
6 * Darius Augulis, Teltonika Inc.
7 *
8 * Desc.:
9 * Implementation of I2C Adapter/Algorithm Driver
10 * for I2C Bus integrated in Freescale i.MX/MXC processors
11 *
12 * Derived from Motorola GSG China I2C example driver
13 *
14 * Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
15 * Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
16 * Copyright (C) 2007 RightHand Technologies, Inc.
17 * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
18 *
19 * Copyright 2013 Freescale Semiconductor, Inc.
20 * Copyright 2020 NXP
21 *
22 */
23
24 #include <linux/acpi.h>
25 #include <linux/clk.h>
26 #include <linux/completion.h>
27 #include <linux/delay.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/dmaengine.h>
30 #include <linux/dmapool.h>
31 #include <linux/err.h>
32 #include <linux/errno.h>
33 #include <linux/gpio/consumer.h>
34 #include <linux/i2c.h>
35 #include <linux/init.h>
36 #include <linux/interrupt.h>
37 #include <linux/io.h>
38 #include <linux/iopoll.h>
39 #include <linux/kernel.h>
40 #include <linux/spinlock.h>
41 #include <linux/hrtimer.h>
42 #include <linux/module.h>
43 #include <linux/of.h>
44 #include <linux/of_dma.h>
45 #include <linux/pinctrl/consumer.h>
46 #include <linux/platform_data/i2c-imx.h>
47 #include <linux/platform_device.h>
48 #include <linux/pm_runtime.h>
49 #include <linux/sched.h>
50 #include <linux/slab.h>
51
52 /* This will be the driver name the kernel reports */
53 #define DRIVER_NAME "imx-i2c"
54
55 #define I2C_IMX_CHECK_DELAY 30000 /* Time to check for bus idle, in NS */
56
57 /*
58 * Enable DMA if transfer byte size is bigger than this threshold.
59 * As the hardware request, it must bigger than 4 bytes.\
60 * I have set '16' here, maybe it's not the best but I think it's
61 * the appropriate.
62 */
63 #define DMA_THRESHOLD 16
64 #define DMA_TIMEOUT 1000
65
66 /* IMX I2C registers:
67 * the I2C register offset is different between SoCs,
68 * to provide support for all these chips, split the
69 * register offset into a fixed base address and a
70 * variable shift value, then the full register offset
71 * will be calculated by
72 * reg_off = ( reg_base_addr << reg_shift)
73 */
74 #define IMX_I2C_IADR 0x00 /* i2c slave address */
75 #define IMX_I2C_IFDR 0x01 /* i2c frequency divider */
76 #define IMX_I2C_I2CR 0x02 /* i2c control */
77 #define IMX_I2C_I2SR 0x03 /* i2c status */
78 #define IMX_I2C_I2DR 0x04 /* i2c transfer data */
79
80 /*
81 * All of the layerscape series SoCs support IBIC register.
82 */
83 #define IMX_I2C_IBIC 0x05 /* i2c bus interrupt config */
84
85 #define IMX_I2C_REGSHIFT 2
86 #define VF610_I2C_REGSHIFT 0
87
88 /* Bits of IMX I2C registers */
89 #define I2SR_RXAK 0x01
90 #define I2SR_IIF 0x02
91 #define I2SR_SRW 0x04
92 #define I2SR_IAL 0x10
93 #define I2SR_IBB 0x20
94 #define I2SR_IAAS 0x40
95 #define I2SR_ICF 0x80
96 #define I2CR_DMAEN 0x02
97 #define I2CR_RSTA 0x04
98 #define I2CR_TXAK 0x08
99 #define I2CR_MTX 0x10
100 #define I2CR_MSTA 0x20
101 #define I2CR_IIEN 0x40
102 #define I2CR_IEN 0x80
103 #define IBIC_BIIE 0x80 /* Bus idle interrupt enable */
104
105 /* register bits different operating codes definition:
106 * 1) I2SR: Interrupt flags clear operation differ between SoCs:
107 * - write zero to clear(w0c) INT flag on i.MX,
108 * - but write one to clear(w1c) INT flag on Vybrid.
109 * 2) I2CR: I2C module enable operation also differ between SoCs:
110 * - set I2CR_IEN bit enable the module on i.MX,
111 * - but clear I2CR_IEN bit enable the module on Vybrid.
112 */
113 #define I2SR_CLR_OPCODE_W0C 0x0
114 #define I2SR_CLR_OPCODE_W1C (I2SR_IAL | I2SR_IIF)
115 #define I2CR_IEN_OPCODE_0 0x0
116 #define I2CR_IEN_OPCODE_1 I2CR_IEN
117
118 #define I2C_PM_TIMEOUT 10 /* ms */
119
120 /*
121 * sorted list of clock divider, register value pairs
122 * taken from table 26-5, p.26-9, Freescale i.MX
123 * Integrated Portable System Processor Reference Manual
124 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
125 *
126 * Duplicated divider values removed from list
127 */
128 struct imx_i2c_clk_pair {
129 u16 div;
130 u16 val;
131 };
132
133 static struct imx_i2c_clk_pair imx_i2c_clk_div[] = {
134 { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
135 { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
136 { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
137 { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B },
138 { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A },
139 { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 },
140 { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 },
141 { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 },
142 { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 },
143 { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B },
144 { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
145 { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
146 { 3072, 0x1E }, { 3840, 0x1F }
147 };
148
149 /* Vybrid VF610 clock divider, register value pairs */
150 static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = {
151 { 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 },
152 { 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 },
153 { 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D },
154 { 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 },
155 { 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 },
156 { 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 },
157 { 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 },
158 { 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 },
159 { 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 },
160 { 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B },
161 { 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 },
162 { 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
163 { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
164 { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
165 { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
166 };
167
168 enum imx_i2c_type {
169 IMX1_I2C,
170 IMX21_I2C,
171 VF610_I2C,
172 };
173
174 struct imx_i2c_hwdata {
175 enum imx_i2c_type devtype;
176 unsigned int regshift;
177 struct imx_i2c_clk_pair *clk_div;
178 unsigned int ndivs;
179 unsigned int i2sr_clr_opcode;
180 unsigned int i2cr_ien_opcode;
181 /*
182 * Errata ERR007805 or e7805:
183 * I2C: When the I2C clock speed is configured for 400 kHz,
184 * the SCL low period violates the I2C spec of 1.3 uS min.
185 */
186 bool has_err007805;
187 };
188
189 struct imx_i2c_dma {
190 struct dma_chan *chan_tx;
191 struct dma_chan *chan_rx;
192 struct dma_chan *chan_using;
193 struct completion cmd_complete;
194 dma_addr_t dma_buf;
195 unsigned int dma_len;
196 enum dma_transfer_direction dma_transfer_dir;
197 enum dma_data_direction dma_data_dir;
198 };
199
200 struct imx_i2c_struct {
201 struct i2c_adapter adapter;
202 struct clk *clk;
203 struct notifier_block clk_change_nb;
204 void __iomem *base;
205 wait_queue_head_t queue;
206 unsigned long i2csr;
207 unsigned int disable_delay;
208 int stopped;
209 unsigned int ifdr; /* IMX_I2C_IFDR */
210 unsigned int cur_clk;
211 unsigned int bitrate;
212 const struct imx_i2c_hwdata *hwdata;
213 struct i2c_bus_recovery_info rinfo;
214
215 struct pinctrl *pinctrl;
216 struct pinctrl_state *pinctrl_pins_default;
217 struct pinctrl_state *pinctrl_pins_gpio;
218
219 struct imx_i2c_dma *dma;
220 struct i2c_client *slave;
221 enum i2c_slave_event last_slave_event;
222
223 /* For checking slave events. */
224 spinlock_t slave_lock;
225 struct hrtimer slave_timer;
226 };
227
228 static const struct imx_i2c_hwdata imx1_i2c_hwdata = {
229 .devtype = IMX1_I2C,
230 .regshift = IMX_I2C_REGSHIFT,
231 .clk_div = imx_i2c_clk_div,
232 .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
233 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
234 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
235
236 };
237
238 static const struct imx_i2c_hwdata imx21_i2c_hwdata = {
239 .devtype = IMX21_I2C,
240 .regshift = IMX_I2C_REGSHIFT,
241 .clk_div = imx_i2c_clk_div,
242 .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
243 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
244 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
245
246 };
247
248 static const struct imx_i2c_hwdata imx6_i2c_hwdata = {
249 .devtype = IMX21_I2C,
250 .regshift = IMX_I2C_REGSHIFT,
251 .clk_div = imx_i2c_clk_div,
252 .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
253 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
254 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
255 .has_err007805 = true,
256 };
257
258 static struct imx_i2c_hwdata vf610_i2c_hwdata = {
259 .devtype = VF610_I2C,
260 .regshift = VF610_I2C_REGSHIFT,
261 .clk_div = vf610_i2c_clk_div,
262 .ndivs = ARRAY_SIZE(vf610_i2c_clk_div),
263 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C,
264 .i2cr_ien_opcode = I2CR_IEN_OPCODE_0,
265
266 };
267
268 static const struct platform_device_id imx_i2c_devtype[] = {
269 {
270 .name = "imx1-i2c",
271 .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata,
272 }, {
273 .name = "imx21-i2c",
274 .driver_data = (kernel_ulong_t)&imx21_i2c_hwdata,
275 }, {
276 /* sentinel */
277 }
278 };
279 MODULE_DEVICE_TABLE(platform, imx_i2c_devtype);
280
281 static const struct of_device_id i2c_imx_dt_ids[] = {
282 { .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, },
283 { .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, },
284 { .compatible = "fsl,imx6q-i2c", .data = &imx6_i2c_hwdata, },
285 { .compatible = "fsl,imx6sl-i2c", .data = &imx6_i2c_hwdata, },
286 { .compatible = "fsl,imx6sll-i2c", .data = &imx6_i2c_hwdata, },
287 { .compatible = "fsl,imx6sx-i2c", .data = &imx6_i2c_hwdata, },
288 { .compatible = "fsl,imx6ul-i2c", .data = &imx6_i2c_hwdata, },
289 { .compatible = "fsl,imx7s-i2c", .data = &imx6_i2c_hwdata, },
290 { .compatible = "fsl,imx8mm-i2c", .data = &imx6_i2c_hwdata, },
291 { .compatible = "fsl,imx8mn-i2c", .data = &imx6_i2c_hwdata, },
292 { .compatible = "fsl,imx8mp-i2c", .data = &imx6_i2c_hwdata, },
293 { .compatible = "fsl,imx8mq-i2c", .data = &imx6_i2c_hwdata, },
294 { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, },
295 { /* sentinel */ }
296 };
297 MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids);
298
299 static const struct acpi_device_id i2c_imx_acpi_ids[] = {
300 {"NXP0001", .driver_data = (kernel_ulong_t)&vf610_i2c_hwdata},
301 { }
302 };
303 MODULE_DEVICE_TABLE(acpi, i2c_imx_acpi_ids);
304
is_imx1_i2c(struct imx_i2c_struct * i2c_imx)305 static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
306 {
307 return i2c_imx->hwdata->devtype == IMX1_I2C;
308 }
309
is_vf610_i2c(struct imx_i2c_struct * i2c_imx)310 static inline int is_vf610_i2c(struct imx_i2c_struct *i2c_imx)
311 {
312 return i2c_imx->hwdata->devtype == VF610_I2C;
313 }
314
imx_i2c_write_reg(unsigned int val,struct imx_i2c_struct * i2c_imx,unsigned int reg)315 static inline void imx_i2c_write_reg(unsigned int val,
316 struct imx_i2c_struct *i2c_imx, unsigned int reg)
317 {
318 writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
319 }
320
imx_i2c_read_reg(struct imx_i2c_struct * i2c_imx,unsigned int reg)321 static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
322 unsigned int reg)
323 {
324 return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
325 }
326
i2c_imx_clear_irq(struct imx_i2c_struct * i2c_imx,unsigned int bits)327 static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits)
328 {
329 unsigned int temp;
330
331 /*
332 * i2sr_clr_opcode is the value to clear all interrupts. Here we want to
333 * clear only <bits>, so we write ~i2sr_clr_opcode with just <bits>
334 * toggled. This is required because i.MX needs W0C and Vybrid uses W1C.
335 */
336 temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits;
337 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
338 }
339
340 /* Set up i2c controller register and i2c status register to default value. */
i2c_imx_reset_regs(struct imx_i2c_struct * i2c_imx)341 static void i2c_imx_reset_regs(struct imx_i2c_struct *i2c_imx)
342 {
343 imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
344 i2c_imx, IMX_I2C_I2CR);
345 i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
346 }
347
348 /* Functions for DMA support */
i2c_imx_dma_request(struct imx_i2c_struct * i2c_imx,dma_addr_t phy_addr)349 static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
350 dma_addr_t phy_addr)
351 {
352 struct imx_i2c_dma *dma;
353 struct dma_slave_config dma_sconfig;
354 struct device *dev = &i2c_imx->adapter.dev;
355 int ret;
356
357 dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
358 if (!dma)
359 return;
360
361 dma->chan_tx = dma_request_chan(dev, "tx");
362 if (IS_ERR(dma->chan_tx)) {
363 ret = PTR_ERR(dma->chan_tx);
364 if (ret != -ENODEV && ret != -EPROBE_DEFER)
365 dev_err(dev, "can't request DMA tx channel (%d)\n", ret);
366 goto fail_al;
367 }
368
369 dma_sconfig.dst_addr = phy_addr +
370 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
371 dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
372 dma_sconfig.dst_maxburst = 1;
373 dma_sconfig.direction = DMA_MEM_TO_DEV;
374 ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig);
375 if (ret < 0) {
376 dev_err(dev, "can't configure tx channel (%d)\n", ret);
377 goto fail_tx;
378 }
379
380 dma->chan_rx = dma_request_chan(dev, "rx");
381 if (IS_ERR(dma->chan_rx)) {
382 ret = PTR_ERR(dma->chan_rx);
383 if (ret != -ENODEV && ret != -EPROBE_DEFER)
384 dev_err(dev, "can't request DMA rx channel (%d)\n", ret);
385 goto fail_tx;
386 }
387
388 dma_sconfig.src_addr = phy_addr +
389 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
390 dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
391 dma_sconfig.src_maxburst = 1;
392 dma_sconfig.direction = DMA_DEV_TO_MEM;
393 ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig);
394 if (ret < 0) {
395 dev_err(dev, "can't configure rx channel (%d)\n", ret);
396 goto fail_rx;
397 }
398
399 i2c_imx->dma = dma;
400 init_completion(&dma->cmd_complete);
401 dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
402 dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
403
404 return;
405
406 fail_rx:
407 dma_release_channel(dma->chan_rx);
408 fail_tx:
409 dma_release_channel(dma->chan_tx);
410 fail_al:
411 devm_kfree(dev, dma);
412 }
413
i2c_imx_dma_callback(void * arg)414 static void i2c_imx_dma_callback(void *arg)
415 {
416 struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg;
417 struct imx_i2c_dma *dma = i2c_imx->dma;
418
419 dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf,
420 dma->dma_len, dma->dma_data_dir);
421 complete(&dma->cmd_complete);
422 }
423
i2c_imx_dma_xfer(struct imx_i2c_struct * i2c_imx,struct i2c_msg * msgs)424 static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx,
425 struct i2c_msg *msgs)
426 {
427 struct imx_i2c_dma *dma = i2c_imx->dma;
428 struct dma_async_tx_descriptor *txdesc;
429 struct device *dev = &i2c_imx->adapter.dev;
430 struct device *chan_dev = dma->chan_using->device->dev;
431
432 dma->dma_buf = dma_map_single(chan_dev, msgs->buf,
433 dma->dma_len, dma->dma_data_dir);
434 if (dma_mapping_error(chan_dev, dma->dma_buf)) {
435 dev_err(dev, "DMA mapping failed\n");
436 goto err_map;
437 }
438
439 txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf,
440 dma->dma_len, dma->dma_transfer_dir,
441 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
442 if (!txdesc) {
443 dev_err(dev, "Not able to get desc for DMA xfer\n");
444 goto err_desc;
445 }
446
447 reinit_completion(&dma->cmd_complete);
448 txdesc->callback = i2c_imx_dma_callback;
449 txdesc->callback_param = i2c_imx;
450 if (dma_submit_error(dmaengine_submit(txdesc))) {
451 dev_err(dev, "DMA submit failed\n");
452 goto err_submit;
453 }
454
455 dma_async_issue_pending(dma->chan_using);
456 return 0;
457
458 err_submit:
459 dmaengine_terminate_sync(dma->chan_using);
460 err_desc:
461 dma_unmap_single(chan_dev, dma->dma_buf,
462 dma->dma_len, dma->dma_data_dir);
463 err_map:
464 return -EINVAL;
465 }
466
i2c_imx_dma_free(struct imx_i2c_struct * i2c_imx)467 static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
468 {
469 struct imx_i2c_dma *dma = i2c_imx->dma;
470
471 dma->dma_buf = 0;
472 dma->dma_len = 0;
473
474 dma_release_channel(dma->chan_tx);
475 dma->chan_tx = NULL;
476
477 dma_release_channel(dma->chan_rx);
478 dma->chan_rx = NULL;
479
480 dma->chan_using = NULL;
481 }
482
i2c_imx_bus_busy(struct imx_i2c_struct * i2c_imx,int for_busy,bool atomic)483 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic)
484 {
485 unsigned long orig_jiffies = jiffies;
486 unsigned int temp;
487
488 while (1) {
489 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
490
491 /* check for arbitration lost */
492 if (temp & I2SR_IAL) {
493 i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
494 return -EAGAIN;
495 }
496
497 if (for_busy && (temp & I2SR_IBB)) {
498 i2c_imx->stopped = 0;
499 break;
500 }
501 if (!for_busy && !(temp & I2SR_IBB)) {
502 i2c_imx->stopped = 1;
503 break;
504 }
505 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
506 dev_dbg(&i2c_imx->adapter.dev,
507 "<%s> I2C bus is busy\n", __func__);
508 return -ETIMEDOUT;
509 }
510 if (atomic)
511 udelay(100);
512 else
513 schedule();
514 }
515
516 return 0;
517 }
518
i2c_imx_trx_complete(struct imx_i2c_struct * i2c_imx,bool atomic)519 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic)
520 {
521 if (atomic) {
522 void __iomem *addr = i2c_imx->base + (IMX_I2C_I2SR << i2c_imx->hwdata->regshift);
523 unsigned int regval;
524
525 /*
526 * The formula for the poll timeout is documented in the RM
527 * Rev.5 on page 1878:
528 * T_min = 10/F_scl
529 * Set the value hard as it is done for the non-atomic use-case.
530 * Use 10 kHz for the calculation since this is the minimum
531 * allowed SMBus frequency. Also add an offset of 100us since it
532 * turned out that the I2SR_IIF bit isn't set correctly within
533 * the minimum timeout in polling mode.
534 */
535 readb_poll_timeout_atomic(addr, regval, regval & I2SR_IIF, 5, 1000 + 100);
536 i2c_imx->i2csr = regval;
537 i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
538 } else {
539 wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
540 }
541
542 if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
543 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
544 return -ETIMEDOUT;
545 }
546
547 /* check for arbitration lost */
548 if (i2c_imx->i2csr & I2SR_IAL) {
549 dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__);
550 i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
551
552 i2c_imx->i2csr = 0;
553 return -EAGAIN;
554 }
555
556 dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
557 i2c_imx->i2csr = 0;
558 return 0;
559 }
560
i2c_imx_acked(struct imx_i2c_struct * i2c_imx)561 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
562 {
563 if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
564 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
565 return -ENXIO; /* No ACK */
566 }
567
568 dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
569 return 0;
570 }
571
i2c_imx_set_clk(struct imx_i2c_struct * i2c_imx,unsigned int i2c_clk_rate)572 static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
573 unsigned int i2c_clk_rate)
574 {
575 struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div;
576 unsigned int div;
577 int i;
578
579 if (i2c_imx->hwdata->has_err007805 && i2c_imx->bitrate > 384000) {
580 dev_dbg(&i2c_imx->adapter.dev,
581 "SoC errata ERR007805 or e7805 applies, bus frequency limited from %d Hz to 384000 Hz.\n",
582 i2c_imx->bitrate);
583 i2c_imx->bitrate = 384000;
584 }
585
586 /* Divider value calculation */
587 if (i2c_imx->cur_clk == i2c_clk_rate)
588 return;
589
590 i2c_imx->cur_clk = i2c_clk_rate;
591
592 div = DIV_ROUND_UP(i2c_clk_rate, i2c_imx->bitrate);
593 if (div < i2c_clk_div[0].div)
594 i = 0;
595 else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div)
596 i = i2c_imx->hwdata->ndivs - 1;
597 else
598 for (i = 0; i2c_clk_div[i].div < div; i++)
599 ;
600
601 /* Store divider value */
602 i2c_imx->ifdr = i2c_clk_div[i].val;
603
604 /*
605 * There dummy delay is calculated.
606 * It should be about one I2C clock period long.
607 * This delay is used in I2C bus disable function
608 * to fix chip hardware bug.
609 */
610 i2c_imx->disable_delay = DIV_ROUND_UP(500000U * i2c_clk_div[i].div,
611 i2c_clk_rate / 2);
612
613 #ifdef CONFIG_I2C_DEBUG_BUS
614 dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n",
615 i2c_clk_rate, div);
616 dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n",
617 i2c_clk_div[i].val, i2c_clk_div[i].div);
618 #endif
619 }
620
i2c_imx_clk_notifier_call(struct notifier_block * nb,unsigned long action,void * data)621 static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
622 unsigned long action, void *data)
623 {
624 struct clk_notifier_data *ndata = data;
625 struct imx_i2c_struct *i2c_imx = container_of(nb,
626 struct imx_i2c_struct,
627 clk_change_nb);
628
629 if (action & POST_RATE_CHANGE)
630 i2c_imx_set_clk(i2c_imx, ndata->new_rate);
631
632 return NOTIFY_OK;
633 }
634
i2c_imx_start(struct imx_i2c_struct * i2c_imx,bool atomic)635 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic)
636 {
637 unsigned int temp = 0;
638 int result;
639
640 imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR);
641 /* Enable I2C controller */
642 imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
643 imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR);
644
645 /* Wait controller to be stable */
646 if (atomic)
647 udelay(50);
648 else
649 usleep_range(50, 150);
650
651 /* Start I2C transaction */
652 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
653 temp |= I2CR_MSTA;
654 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
655 result = i2c_imx_bus_busy(i2c_imx, 1, atomic);
656 if (result)
657 return result;
658
659 temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
660 if (atomic)
661 temp &= ~I2CR_IIEN; /* Disable interrupt */
662
663 temp &= ~I2CR_DMAEN;
664 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
665 return result;
666 }
667
i2c_imx_stop(struct imx_i2c_struct * i2c_imx,bool atomic)668 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic)
669 {
670 unsigned int temp = 0;
671
672 if (!i2c_imx->stopped) {
673 /* Stop I2C transaction */
674 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
675 if (!(temp & I2CR_MSTA))
676 i2c_imx->stopped = 1;
677 temp &= ~(I2CR_MSTA | I2CR_MTX);
678 if (i2c_imx->dma)
679 temp &= ~I2CR_DMAEN;
680 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
681 }
682 if (is_imx1_i2c(i2c_imx)) {
683 /*
684 * This delay caused by an i.MXL hardware bug.
685 * If no (or too short) delay, no "STOP" bit will be generated.
686 */
687 udelay(i2c_imx->disable_delay);
688 }
689
690 if (!i2c_imx->stopped)
691 i2c_imx_bus_busy(i2c_imx, 0, atomic);
692
693 /* Disable I2C controller */
694 temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
695 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
696 }
697
698 /*
699 * Enable bus idle interrupts
700 * Note: IBIC register will be cleared after disabled i2c module.
701 * All of layerscape series SoCs support IBIC register.
702 */
i2c_imx_enable_bus_idle(struct imx_i2c_struct * i2c_imx)703 static void i2c_imx_enable_bus_idle(struct imx_i2c_struct *i2c_imx)
704 {
705 if (is_vf610_i2c(i2c_imx)) {
706 unsigned int temp;
707
708 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_IBIC);
709 temp |= IBIC_BIIE;
710 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_IBIC);
711 }
712 }
713
i2c_imx_slave_event(struct imx_i2c_struct * i2c_imx,enum i2c_slave_event event,u8 * val)714 static void i2c_imx_slave_event(struct imx_i2c_struct *i2c_imx,
715 enum i2c_slave_event event, u8 *val)
716 {
717 i2c_slave_event(i2c_imx->slave, event, val);
718 i2c_imx->last_slave_event = event;
719 }
720
i2c_imx_slave_finish_op(struct imx_i2c_struct * i2c_imx)721 static void i2c_imx_slave_finish_op(struct imx_i2c_struct *i2c_imx)
722 {
723 u8 val = 0;
724
725 while (i2c_imx->last_slave_event != I2C_SLAVE_STOP) {
726 switch (i2c_imx->last_slave_event) {
727 case I2C_SLAVE_READ_REQUESTED:
728 i2c_imx_slave_event(i2c_imx, I2C_SLAVE_READ_PROCESSED,
729 &val);
730 break;
731
732 case I2C_SLAVE_WRITE_REQUESTED:
733 case I2C_SLAVE_READ_PROCESSED:
734 case I2C_SLAVE_WRITE_RECEIVED:
735 i2c_imx_slave_event(i2c_imx, I2C_SLAVE_STOP, &val);
736 break;
737
738 case I2C_SLAVE_STOP:
739 break;
740 }
741 }
742 }
743
744 /* Returns true if the timer should be restarted, false if not. */
i2c_imx_slave_handle(struct imx_i2c_struct * i2c_imx,unsigned int status,unsigned int ctl)745 static irqreturn_t i2c_imx_slave_handle(struct imx_i2c_struct *i2c_imx,
746 unsigned int status, unsigned int ctl)
747 {
748 u8 value = 0;
749
750 if (status & I2SR_IAL) { /* Arbitration lost */
751 i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
752 if (!(status & I2SR_IAAS))
753 return IRQ_HANDLED;
754 }
755
756 if (!(status & I2SR_IBB)) {
757 /* No master on the bus, that could mean a stop condition. */
758 i2c_imx_slave_finish_op(i2c_imx);
759 return IRQ_HANDLED;
760 }
761
762 if (!(status & I2SR_ICF))
763 /* Data transfer still in progress, ignore this. */
764 goto out;
765
766 if (status & I2SR_IAAS) { /* Addressed as a slave */
767 i2c_imx_slave_finish_op(i2c_imx);
768 if (status & I2SR_SRW) { /* Master wants to read from us*/
769 dev_dbg(&i2c_imx->adapter.dev, "read requested");
770 i2c_imx_slave_event(i2c_imx,
771 I2C_SLAVE_READ_REQUESTED, &value);
772
773 /* Slave transmit */
774 ctl |= I2CR_MTX;
775 imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
776
777 /* Send data */
778 imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR);
779 } else { /* Master wants to write to us */
780 dev_dbg(&i2c_imx->adapter.dev, "write requested");
781 i2c_imx_slave_event(i2c_imx,
782 I2C_SLAVE_WRITE_REQUESTED, &value);
783
784 /* Slave receive */
785 ctl &= ~I2CR_MTX;
786 imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
787 /* Dummy read */
788 imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
789 }
790 } else if (!(ctl & I2CR_MTX)) { /* Receive mode */
791 value = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
792 i2c_imx_slave_event(i2c_imx,
793 I2C_SLAVE_WRITE_RECEIVED, &value);
794 } else if (!(status & I2SR_RXAK)) { /* Transmit mode received ACK */
795 ctl |= I2CR_MTX;
796 imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
797
798 i2c_imx_slave_event(i2c_imx,
799 I2C_SLAVE_READ_PROCESSED, &value);
800
801 imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR);
802 } else { /* Transmit mode received NAK, operation is done */
803 ctl &= ~I2CR_MTX;
804 imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR);
805 imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
806
807 /* flag the last byte as processed */
808 i2c_imx_slave_event(i2c_imx,
809 I2C_SLAVE_READ_PROCESSED, &value);
810
811 i2c_imx_slave_finish_op(i2c_imx);
812 return IRQ_HANDLED;
813 }
814
815 out:
816 /*
817 * No need to check the return value here. If it returns 0 or
818 * 1, then everything is fine. If it returns -1, then the
819 * timer is running in the handler. This will still work,
820 * though it may be redone (or already have been done) by the
821 * timer function.
822 */
823 hrtimer_try_to_cancel(&i2c_imx->slave_timer);
824 hrtimer_forward_now(&i2c_imx->slave_timer, I2C_IMX_CHECK_DELAY);
825 hrtimer_restart(&i2c_imx->slave_timer);
826 return IRQ_HANDLED;
827 }
828
i2c_imx_slave_timeout(struct hrtimer * t)829 static enum hrtimer_restart i2c_imx_slave_timeout(struct hrtimer *t)
830 {
831 struct imx_i2c_struct *i2c_imx = container_of(t, struct imx_i2c_struct,
832 slave_timer);
833 unsigned int ctl, status;
834 unsigned long flags;
835
836 spin_lock_irqsave(&i2c_imx->slave_lock, flags);
837 status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
838 ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
839 i2c_imx_slave_handle(i2c_imx, status, ctl);
840 spin_unlock_irqrestore(&i2c_imx->slave_lock, flags);
841 return HRTIMER_NORESTART;
842 }
843
i2c_imx_slave_init(struct imx_i2c_struct * i2c_imx)844 static void i2c_imx_slave_init(struct imx_i2c_struct *i2c_imx)
845 {
846 int temp;
847
848 /* Set slave addr. */
849 imx_i2c_write_reg((i2c_imx->slave->addr << 1), i2c_imx, IMX_I2C_IADR);
850
851 i2c_imx_reset_regs(i2c_imx);
852
853 /* Enable module */
854 temp = i2c_imx->hwdata->i2cr_ien_opcode;
855 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
856
857 /* Enable interrupt from i2c module */
858 temp |= I2CR_IIEN;
859 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
860
861 i2c_imx_enable_bus_idle(i2c_imx);
862 }
863
i2c_imx_reg_slave(struct i2c_client * client)864 static int i2c_imx_reg_slave(struct i2c_client *client)
865 {
866 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter);
867 int ret;
868
869 if (i2c_imx->slave)
870 return -EBUSY;
871
872 i2c_imx->slave = client;
873 i2c_imx->last_slave_event = I2C_SLAVE_STOP;
874
875 /* Resume */
876 ret = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent);
877 if (ret < 0) {
878 dev_err(&i2c_imx->adapter.dev, "failed to resume i2c controller");
879 return ret;
880 }
881
882 i2c_imx_slave_init(i2c_imx);
883
884 return 0;
885 }
886
i2c_imx_unreg_slave(struct i2c_client * client)887 static int i2c_imx_unreg_slave(struct i2c_client *client)
888 {
889 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter);
890 int ret;
891
892 if (!i2c_imx->slave)
893 return -EINVAL;
894
895 /* Reset slave address. */
896 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
897
898 i2c_imx_reset_regs(i2c_imx);
899
900 i2c_imx->slave = NULL;
901
902 /* Suspend */
903 ret = pm_runtime_put_sync(i2c_imx->adapter.dev.parent);
904 if (ret < 0)
905 dev_err(&i2c_imx->adapter.dev, "failed to suspend i2c controller");
906
907 return ret;
908 }
909
i2c_imx_master_isr(struct imx_i2c_struct * i2c_imx,unsigned int status)910 static irqreturn_t i2c_imx_master_isr(struct imx_i2c_struct *i2c_imx, unsigned int status)
911 {
912 /* save status register */
913 i2c_imx->i2csr = status;
914 wake_up(&i2c_imx->queue);
915
916 return IRQ_HANDLED;
917 }
918
i2c_imx_isr(int irq,void * dev_id)919 static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
920 {
921 struct imx_i2c_struct *i2c_imx = dev_id;
922 unsigned int ctl, status;
923 unsigned long flags;
924
925 spin_lock_irqsave(&i2c_imx->slave_lock, flags);
926 status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
927 ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
928
929 if (status & I2SR_IIF) {
930 i2c_imx_clear_irq(i2c_imx, I2SR_IIF);
931 if (i2c_imx->slave) {
932 if (!(ctl & I2CR_MSTA)) {
933 irqreturn_t ret;
934
935 ret = i2c_imx_slave_handle(i2c_imx,
936 status, ctl);
937 spin_unlock_irqrestore(&i2c_imx->slave_lock,
938 flags);
939 return ret;
940 }
941 i2c_imx_slave_finish_op(i2c_imx);
942 }
943 spin_unlock_irqrestore(&i2c_imx->slave_lock, flags);
944 return i2c_imx_master_isr(i2c_imx, status);
945 }
946 spin_unlock_irqrestore(&i2c_imx->slave_lock, flags);
947
948 return IRQ_NONE;
949 }
950
i2c_imx_dma_write(struct imx_i2c_struct * i2c_imx,struct i2c_msg * msgs)951 static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx,
952 struct i2c_msg *msgs)
953 {
954 int result;
955 unsigned long time_left;
956 unsigned int temp = 0;
957 unsigned long orig_jiffies = jiffies;
958 struct imx_i2c_dma *dma = i2c_imx->dma;
959 struct device *dev = &i2c_imx->adapter.dev;
960
961 dma->chan_using = dma->chan_tx;
962 dma->dma_transfer_dir = DMA_MEM_TO_DEV;
963 dma->dma_data_dir = DMA_TO_DEVICE;
964 dma->dma_len = msgs->len - 1;
965 result = i2c_imx_dma_xfer(i2c_imx, msgs);
966 if (result)
967 return result;
968
969 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
970 temp |= I2CR_DMAEN;
971 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
972
973 /*
974 * Write slave address.
975 * The first byte must be transmitted by the CPU.
976 */
977 imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
978 time_left = wait_for_completion_timeout(
979 &i2c_imx->dma->cmd_complete,
980 msecs_to_jiffies(DMA_TIMEOUT));
981 if (time_left == 0) {
982 dmaengine_terminate_sync(dma->chan_using);
983 return -ETIMEDOUT;
984 }
985
986 /* Waiting for transfer complete. */
987 while (1) {
988 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
989 if (temp & I2SR_ICF)
990 break;
991 if (time_after(jiffies, orig_jiffies +
992 msecs_to_jiffies(DMA_TIMEOUT))) {
993 dev_dbg(dev, "<%s> Timeout\n", __func__);
994 return -ETIMEDOUT;
995 }
996 schedule();
997 }
998
999 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1000 temp &= ~I2CR_DMAEN;
1001 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1002
1003 /* The last data byte must be transferred by the CPU. */
1004 imx_i2c_write_reg(msgs->buf[msgs->len-1],
1005 i2c_imx, IMX_I2C_I2DR);
1006 result = i2c_imx_trx_complete(i2c_imx, false);
1007 if (result)
1008 return result;
1009
1010 return i2c_imx_acked(i2c_imx);
1011 }
1012
i2c_imx_dma_read(struct imx_i2c_struct * i2c_imx,struct i2c_msg * msgs,bool is_lastmsg)1013 static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
1014 struct i2c_msg *msgs, bool is_lastmsg)
1015 {
1016 int result;
1017 unsigned long time_left;
1018 unsigned int temp;
1019 unsigned long orig_jiffies = jiffies;
1020 struct imx_i2c_dma *dma = i2c_imx->dma;
1021 struct device *dev = &i2c_imx->adapter.dev;
1022
1023
1024 dma->chan_using = dma->chan_rx;
1025 dma->dma_transfer_dir = DMA_DEV_TO_MEM;
1026 dma->dma_data_dir = DMA_FROM_DEVICE;
1027 /* The last two data bytes must be transferred by the CPU. */
1028 dma->dma_len = msgs->len - 2;
1029 result = i2c_imx_dma_xfer(i2c_imx, msgs);
1030 if (result)
1031 return result;
1032
1033 time_left = wait_for_completion_timeout(
1034 &i2c_imx->dma->cmd_complete,
1035 msecs_to_jiffies(DMA_TIMEOUT));
1036 if (time_left == 0) {
1037 dmaengine_terminate_sync(dma->chan_using);
1038 return -ETIMEDOUT;
1039 }
1040
1041 /* waiting for transfer complete. */
1042 while (1) {
1043 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
1044 if (temp & I2SR_ICF)
1045 break;
1046 if (time_after(jiffies, orig_jiffies +
1047 msecs_to_jiffies(DMA_TIMEOUT))) {
1048 dev_dbg(dev, "<%s> Timeout\n", __func__);
1049 return -ETIMEDOUT;
1050 }
1051 schedule();
1052 }
1053
1054 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1055 temp &= ~I2CR_DMAEN;
1056 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1057
1058 /* read n-1 byte data */
1059 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1060 temp |= I2CR_TXAK;
1061 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1062
1063 msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1064 /* read n byte data */
1065 result = i2c_imx_trx_complete(i2c_imx, false);
1066 if (result)
1067 return result;
1068
1069 if (is_lastmsg) {
1070 /*
1071 * It must generate STOP before read I2DR to prevent
1072 * controller from generating another clock cycle
1073 */
1074 dev_dbg(dev, "<%s> clear MSTA\n", __func__);
1075 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1076 if (!(temp & I2CR_MSTA))
1077 i2c_imx->stopped = 1;
1078 temp &= ~(I2CR_MSTA | I2CR_MTX);
1079 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1080 if (!i2c_imx->stopped)
1081 i2c_imx_bus_busy(i2c_imx, 0, false);
1082 } else {
1083 /*
1084 * For i2c master receiver repeat restart operation like:
1085 * read -> repeat MSTA -> read/write
1086 * The controller must set MTX before read the last byte in
1087 * the first read operation, otherwise the first read cost
1088 * one extra clock cycle.
1089 */
1090 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1091 temp |= I2CR_MTX;
1092 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1093 }
1094 msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1095
1096 return 0;
1097 }
1098
i2c_imx_write(struct imx_i2c_struct * i2c_imx,struct i2c_msg * msgs,bool atomic)1099 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
1100 bool atomic)
1101 {
1102 int i, result;
1103
1104 dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
1105 __func__, i2c_8bit_addr_from_msg(msgs));
1106
1107 /* write slave address */
1108 imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
1109 result = i2c_imx_trx_complete(i2c_imx, atomic);
1110 if (result)
1111 return result;
1112 result = i2c_imx_acked(i2c_imx);
1113 if (result)
1114 return result;
1115 dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
1116
1117 /* write data */
1118 for (i = 0; i < msgs->len; i++) {
1119 dev_dbg(&i2c_imx->adapter.dev,
1120 "<%s> write byte: B%d=0x%X\n",
1121 __func__, i, msgs->buf[i]);
1122 imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR);
1123 result = i2c_imx_trx_complete(i2c_imx, atomic);
1124 if (result)
1125 return result;
1126 result = i2c_imx_acked(i2c_imx);
1127 if (result)
1128 return result;
1129 }
1130 return 0;
1131 }
1132
i2c_imx_read(struct imx_i2c_struct * i2c_imx,struct i2c_msg * msgs,bool is_lastmsg,bool atomic)1133 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
1134 bool is_lastmsg, bool atomic)
1135 {
1136 int i, result;
1137 unsigned int temp;
1138 int block_data = msgs->flags & I2C_M_RECV_LEN;
1139 int use_dma = i2c_imx->dma && msgs->flags & I2C_M_DMA_SAFE &&
1140 msgs->len >= DMA_THRESHOLD && !block_data;
1141
1142 dev_dbg(&i2c_imx->adapter.dev,
1143 "<%s> write slave address: addr=0x%x\n",
1144 __func__, i2c_8bit_addr_from_msg(msgs));
1145
1146 /* write slave address */
1147 imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR);
1148 result = i2c_imx_trx_complete(i2c_imx, atomic);
1149 if (result)
1150 return result;
1151 result = i2c_imx_acked(i2c_imx);
1152 if (result)
1153 return result;
1154
1155 dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
1156
1157 /* setup bus to read data */
1158 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1159 temp &= ~I2CR_MTX;
1160
1161 /*
1162 * Reset the I2CR_TXAK flag initially for SMBus block read since the
1163 * length is unknown
1164 */
1165 if ((msgs->len - 1) || block_data)
1166 temp &= ~I2CR_TXAK;
1167 if (use_dma)
1168 temp |= I2CR_DMAEN;
1169 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1170 imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
1171
1172 dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
1173
1174 if (use_dma)
1175 return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg);
1176
1177 /* read data */
1178 for (i = 0; i < msgs->len; i++) {
1179 u8 len = 0;
1180
1181 result = i2c_imx_trx_complete(i2c_imx, atomic);
1182 if (result)
1183 return result;
1184 /*
1185 * First byte is the length of remaining packet
1186 * in the SMBus block data read. Add it to
1187 * msgs->len.
1188 */
1189 if ((!i) && block_data) {
1190 len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1191 if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX))
1192 return -EPROTO;
1193 dev_dbg(&i2c_imx->adapter.dev,
1194 "<%s> read length: 0x%X\n",
1195 __func__, len);
1196 msgs->len += len;
1197 }
1198 if (i == (msgs->len - 1)) {
1199 if (is_lastmsg) {
1200 /*
1201 * It must generate STOP before read I2DR to prevent
1202 * controller from generating another clock cycle
1203 */
1204 dev_dbg(&i2c_imx->adapter.dev,
1205 "<%s> clear MSTA\n", __func__);
1206 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1207 if (!(temp & I2CR_MSTA))
1208 i2c_imx->stopped = 1;
1209 temp &= ~(I2CR_MSTA | I2CR_MTX);
1210 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1211 if (!i2c_imx->stopped)
1212 i2c_imx_bus_busy(i2c_imx, 0, atomic);
1213 } else {
1214 /*
1215 * For i2c master receiver repeat restart operation like:
1216 * read -> repeat MSTA -> read/write
1217 * The controller must set MTX before read the last byte in
1218 * the first read operation, otherwise the first read cost
1219 * one extra clock cycle.
1220 */
1221 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1222 temp |= I2CR_MTX;
1223 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1224 }
1225 } else if (i == (msgs->len - 2)) {
1226 dev_dbg(&i2c_imx->adapter.dev,
1227 "<%s> set TXAK\n", __func__);
1228 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1229 temp |= I2CR_TXAK;
1230 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1231 }
1232 if ((!i) && block_data)
1233 msgs->buf[0] = len;
1234 else
1235 msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
1236 dev_dbg(&i2c_imx->adapter.dev,
1237 "<%s> read byte: B%d=0x%X\n",
1238 __func__, i, msgs->buf[i]);
1239 }
1240 return 0;
1241 }
1242
i2c_imx_xfer_common(struct i2c_adapter * adapter,struct i2c_msg * msgs,int num,bool atomic)1243 static int i2c_imx_xfer_common(struct i2c_adapter *adapter,
1244 struct i2c_msg *msgs, int num, bool atomic)
1245 {
1246 unsigned int i, temp;
1247 int result;
1248 bool is_lastmsg = false;
1249 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
1250
1251 /* Start I2C transfer */
1252 result = i2c_imx_start(i2c_imx, atomic);
1253 if (result) {
1254 /*
1255 * Bus recovery uses gpiod_get_value_cansleep() which is not
1256 * allowed within atomic context.
1257 */
1258 if (!atomic && i2c_imx->adapter.bus_recovery_info) {
1259 i2c_recover_bus(&i2c_imx->adapter);
1260 result = i2c_imx_start(i2c_imx, atomic);
1261 }
1262 }
1263
1264 if (result)
1265 goto fail0;
1266
1267 /* read/write data */
1268 for (i = 0; i < num; i++) {
1269 if (i == num - 1)
1270 is_lastmsg = true;
1271
1272 if (i) {
1273 dev_dbg(&i2c_imx->adapter.dev,
1274 "<%s> repeated start\n", __func__);
1275 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1276 temp |= I2CR_RSTA;
1277 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
1278 result = i2c_imx_bus_busy(i2c_imx, 1, atomic);
1279 if (result)
1280 goto fail0;
1281 }
1282 dev_dbg(&i2c_imx->adapter.dev,
1283 "<%s> transfer message: %d\n", __func__, i);
1284 /* write/read data */
1285 #ifdef CONFIG_I2C_DEBUG_BUS
1286 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
1287 dev_dbg(&i2c_imx->adapter.dev,
1288 "<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
1289 __func__,
1290 (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
1291 (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
1292 (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
1293 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
1294 dev_dbg(&i2c_imx->adapter.dev,
1295 "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
1296 __func__,
1297 (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
1298 (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
1299 (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
1300 (temp & I2SR_RXAK ? 1 : 0));
1301 #endif
1302 if (msgs[i].flags & I2C_M_RD) {
1303 result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg, atomic);
1304 } else {
1305 if (!atomic &&
1306 i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD &&
1307 msgs[i].flags & I2C_M_DMA_SAFE)
1308 result = i2c_imx_dma_write(i2c_imx, &msgs[i]);
1309 else
1310 result = i2c_imx_write(i2c_imx, &msgs[i], atomic);
1311 }
1312 if (result)
1313 goto fail0;
1314 }
1315
1316 fail0:
1317 /* Stop I2C transfer */
1318 i2c_imx_stop(i2c_imx, atomic);
1319
1320 dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
1321 (result < 0) ? "error" : "success msg",
1322 (result < 0) ? result : num);
1323 /* After data is transferred, switch to slave mode(as a receiver) */
1324 if (i2c_imx->slave)
1325 i2c_imx_slave_init(i2c_imx);
1326
1327 return (result < 0) ? result : num;
1328 }
1329
i2c_imx_xfer(struct i2c_adapter * adapter,struct i2c_msg * msgs,int num)1330 static int i2c_imx_xfer(struct i2c_adapter *adapter,
1331 struct i2c_msg *msgs, int num)
1332 {
1333 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
1334 int result;
1335
1336 result = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent);
1337 if (result < 0)
1338 return result;
1339
1340 result = i2c_imx_xfer_common(adapter, msgs, num, false);
1341
1342 pm_runtime_mark_last_busy(i2c_imx->adapter.dev.parent);
1343 pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent);
1344
1345 return result;
1346 }
1347
i2c_imx_xfer_atomic(struct i2c_adapter * adapter,struct i2c_msg * msgs,int num)1348 static int i2c_imx_xfer_atomic(struct i2c_adapter *adapter,
1349 struct i2c_msg *msgs, int num)
1350 {
1351 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
1352 int result;
1353
1354 result = clk_enable(i2c_imx->clk);
1355 if (result)
1356 return result;
1357
1358 result = i2c_imx_xfer_common(adapter, msgs, num, true);
1359
1360 clk_disable(i2c_imx->clk);
1361
1362 return result;
1363 }
1364
i2c_imx_prepare_recovery(struct i2c_adapter * adap)1365 static void i2c_imx_prepare_recovery(struct i2c_adapter *adap)
1366 {
1367 struct imx_i2c_struct *i2c_imx;
1368
1369 i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
1370
1371 pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio);
1372 }
1373
i2c_imx_unprepare_recovery(struct i2c_adapter * adap)1374 static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
1375 {
1376 struct imx_i2c_struct *i2c_imx;
1377
1378 i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
1379
1380 pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
1381 }
1382
1383 /*
1384 * We switch SCL and SDA to their GPIO function and do some bitbanging
1385 * for bus recovery. These alternative pinmux settings can be
1386 * described in the device tree by a separate pinctrl state "gpio". If
1387 * this is missing this is not a big problem, the only implication is
1388 * that we can't do bus recovery.
1389 */
i2c_imx_init_recovery_info(struct imx_i2c_struct * i2c_imx,struct platform_device * pdev)1390 static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
1391 struct platform_device *pdev)
1392 {
1393 struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
1394
1395 i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
1396 if (!i2c_imx->pinctrl) {
1397 dev_info(&pdev->dev, "pinctrl unavailable, bus recovery not supported\n");
1398 return 0;
1399 }
1400 if (IS_ERR(i2c_imx->pinctrl)) {
1401 dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
1402 return PTR_ERR(i2c_imx->pinctrl);
1403 }
1404
1405 i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
1406 PINCTRL_STATE_DEFAULT);
1407 i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
1408 "gpio");
1409 rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN);
1410 rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
1411
1412 if (PTR_ERR(rinfo->sda_gpiod) == -EPROBE_DEFER ||
1413 PTR_ERR(rinfo->scl_gpiod) == -EPROBE_DEFER) {
1414 return -EPROBE_DEFER;
1415 } else if (IS_ERR(rinfo->sda_gpiod) ||
1416 IS_ERR(rinfo->scl_gpiod) ||
1417 IS_ERR(i2c_imx->pinctrl_pins_default) ||
1418 IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
1419 dev_dbg(&pdev->dev, "recovery information incomplete\n");
1420 return 0;
1421 }
1422
1423 dev_dbg(&pdev->dev, "using scl%s for recovery\n",
1424 rinfo->sda_gpiod ? ",sda" : "");
1425
1426 rinfo->prepare_recovery = i2c_imx_prepare_recovery;
1427 rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
1428 rinfo->recover_bus = i2c_generic_scl_recovery;
1429 i2c_imx->adapter.bus_recovery_info = rinfo;
1430
1431 return 0;
1432 }
1433
i2c_imx_func(struct i2c_adapter * adapter)1434 static u32 i2c_imx_func(struct i2c_adapter *adapter)
1435 {
1436 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
1437 | I2C_FUNC_SMBUS_READ_BLOCK_DATA;
1438 }
1439
1440 static const struct i2c_algorithm i2c_imx_algo = {
1441 .master_xfer = i2c_imx_xfer,
1442 .master_xfer_atomic = i2c_imx_xfer_atomic,
1443 .functionality = i2c_imx_func,
1444 .reg_slave = i2c_imx_reg_slave,
1445 .unreg_slave = i2c_imx_unreg_slave,
1446 };
1447
i2c_imx_probe(struct platform_device * pdev)1448 static int i2c_imx_probe(struct platform_device *pdev)
1449 {
1450 struct imx_i2c_struct *i2c_imx;
1451 struct resource *res;
1452 struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
1453 void __iomem *base;
1454 int irq, ret;
1455 dma_addr_t phy_addr;
1456 const struct imx_i2c_hwdata *match;
1457
1458 irq = platform_get_irq(pdev, 0);
1459 if (irq < 0)
1460 return irq;
1461
1462 base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1463 if (IS_ERR(base))
1464 return PTR_ERR(base);
1465
1466 phy_addr = (dma_addr_t)res->start;
1467 i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL);
1468 if (!i2c_imx)
1469 return -ENOMEM;
1470
1471 spin_lock_init(&i2c_imx->slave_lock);
1472 hrtimer_init(&i2c_imx->slave_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1473 i2c_imx->slave_timer.function = i2c_imx_slave_timeout;
1474
1475 match = device_get_match_data(&pdev->dev);
1476 if (match)
1477 i2c_imx->hwdata = match;
1478 else
1479 i2c_imx->hwdata = (struct imx_i2c_hwdata *)
1480 platform_get_device_id(pdev)->driver_data;
1481
1482 /* Setup i2c_imx driver structure */
1483 strscpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
1484 i2c_imx->adapter.owner = THIS_MODULE;
1485 i2c_imx->adapter.algo = &i2c_imx_algo;
1486 i2c_imx->adapter.dev.parent = &pdev->dev;
1487 i2c_imx->adapter.nr = pdev->id;
1488 i2c_imx->adapter.dev.of_node = pdev->dev.of_node;
1489 i2c_imx->base = base;
1490 ACPI_COMPANION_SET(&i2c_imx->adapter.dev, ACPI_COMPANION(&pdev->dev));
1491
1492 /* Get I2C clock */
1493 i2c_imx->clk = devm_clk_get_enabled(&pdev->dev, NULL);
1494 if (IS_ERR(i2c_imx->clk))
1495 return dev_err_probe(&pdev->dev, PTR_ERR(i2c_imx->clk),
1496 "can't get I2C clock\n");
1497
1498 /* Init queue */
1499 init_waitqueue_head(&i2c_imx->queue);
1500
1501 /* Set up adapter data */
1502 i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
1503
1504 /* Set up platform driver data */
1505 platform_set_drvdata(pdev, i2c_imx);
1506
1507 pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
1508 pm_runtime_use_autosuspend(&pdev->dev);
1509 pm_runtime_set_active(&pdev->dev);
1510 pm_runtime_enable(&pdev->dev);
1511
1512 ret = pm_runtime_get_sync(&pdev->dev);
1513 if (ret < 0)
1514 goto rpm_disable;
1515
1516 /* Request IRQ */
1517 ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED, pdev->name, i2c_imx);
1518 if (ret) {
1519 dev_err(&pdev->dev, "can't claim irq %d\n", irq);
1520 goto rpm_disable;
1521 }
1522
1523 /* Set up clock divider */
1524 i2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
1525 ret = of_property_read_u32(pdev->dev.of_node,
1526 "clock-frequency", &i2c_imx->bitrate);
1527 if (ret < 0 && pdata && pdata->bitrate)
1528 i2c_imx->bitrate = pdata->bitrate;
1529 i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call;
1530 clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb);
1531 i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
1532
1533 i2c_imx_reset_regs(i2c_imx);
1534
1535 /* Init optional bus recovery function */
1536 ret = i2c_imx_init_recovery_info(i2c_imx, pdev);
1537 /* Give it another chance if pinctrl used is not ready yet */
1538 if (ret == -EPROBE_DEFER)
1539 goto clk_notifier_unregister;
1540
1541 /* Add I2C adapter */
1542 ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
1543 if (ret < 0)
1544 goto clk_notifier_unregister;
1545
1546 pm_runtime_mark_last_busy(&pdev->dev);
1547 pm_runtime_put_autosuspend(&pdev->dev);
1548
1549 dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
1550 dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
1551 dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
1552 i2c_imx->adapter.name);
1553 dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
1554
1555 /* Init DMA config if supported */
1556 i2c_imx_dma_request(i2c_imx, phy_addr);
1557
1558 return 0; /* Return OK */
1559
1560 clk_notifier_unregister:
1561 clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
1562 free_irq(irq, i2c_imx);
1563 rpm_disable:
1564 pm_runtime_put_noidle(&pdev->dev);
1565 pm_runtime_disable(&pdev->dev);
1566 pm_runtime_set_suspended(&pdev->dev);
1567 pm_runtime_dont_use_autosuspend(&pdev->dev);
1568 return ret;
1569 }
1570
i2c_imx_remove(struct platform_device * pdev)1571 static void i2c_imx_remove(struct platform_device *pdev)
1572 {
1573 struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
1574 int irq, ret;
1575
1576 ret = pm_runtime_get_sync(&pdev->dev);
1577
1578 hrtimer_cancel(&i2c_imx->slave_timer);
1579
1580 /* remove adapter */
1581 dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
1582 i2c_del_adapter(&i2c_imx->adapter);
1583
1584 if (i2c_imx->dma)
1585 i2c_imx_dma_free(i2c_imx);
1586
1587 if (ret >= 0) {
1588 /* setup chip registers to defaults */
1589 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
1590 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR);
1591 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
1592 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
1593 }
1594
1595 clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
1596 irq = platform_get_irq(pdev, 0);
1597 if (irq >= 0)
1598 free_irq(irq, i2c_imx);
1599
1600 pm_runtime_put_noidle(&pdev->dev);
1601 pm_runtime_disable(&pdev->dev);
1602 }
1603
i2c_imx_runtime_suspend(struct device * dev)1604 static int __maybe_unused i2c_imx_runtime_suspend(struct device *dev)
1605 {
1606 struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
1607
1608 clk_disable(i2c_imx->clk);
1609
1610 return 0;
1611 }
1612
i2c_imx_runtime_resume(struct device * dev)1613 static int __maybe_unused i2c_imx_runtime_resume(struct device *dev)
1614 {
1615 struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
1616 int ret;
1617
1618 ret = clk_enable(i2c_imx->clk);
1619 if (ret)
1620 dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);
1621
1622 return ret;
1623 }
1624
1625 static const struct dev_pm_ops i2c_imx_pm_ops = {
1626 SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend,
1627 i2c_imx_runtime_resume, NULL)
1628 };
1629
1630 static struct platform_driver i2c_imx_driver = {
1631 .probe = i2c_imx_probe,
1632 .remove_new = i2c_imx_remove,
1633 .driver = {
1634 .name = DRIVER_NAME,
1635 .pm = &i2c_imx_pm_ops,
1636 .of_match_table = i2c_imx_dt_ids,
1637 .acpi_match_table = i2c_imx_acpi_ids,
1638 },
1639 .id_table = imx_i2c_devtype,
1640 };
1641
i2c_adap_imx_init(void)1642 static int __init i2c_adap_imx_init(void)
1643 {
1644 return platform_driver_register(&i2c_imx_driver);
1645 }
1646 subsys_initcall(i2c_adap_imx_init);
1647
i2c_adap_imx_exit(void)1648 static void __exit i2c_adap_imx_exit(void)
1649 {
1650 platform_driver_unregister(&i2c_imx_driver);
1651 }
1652 module_exit(i2c_adap_imx_exit);
1653
1654 MODULE_LICENSE("GPL");
1655 MODULE_AUTHOR("Darius Augulis");
1656 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
1657 MODULE_ALIAS("platform:" DRIVER_NAME);
1658