1/*
2 * Copyright (C) 2013 NVIDIA Corporation
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission.  The copyright holders make no representations
11 * about the suitability of this software for any purpose.  It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#include <linux/clk.h>
24#include <linux/delay.h>
25#include <linux/host1x.h>
26#include <linux/io.h>
27#include <linux/of_platform.h>
28#include <linux/platform_device.h>
29#include <linux/slab.h>
30
31#include "dev.h"
32
33#define MIPI_CAL_CTRL			0x00
34#define MIPI_CAL_CTRL_NOISE_FILTER(x)	(((x) & 0xf) << 26)
35#define MIPI_CAL_CTRL_PRESCALE(x)	(((x) & 0x3) << 24)
36#define MIPI_CAL_CTRL_CLKEN_OVR		(1 << 4)
37#define MIPI_CAL_CTRL_START		(1 << 0)
38
39#define MIPI_CAL_AUTOCAL_CTRL		0x01
40
41#define MIPI_CAL_STATUS			0x02
42#define MIPI_CAL_STATUS_DONE		(1 << 16)
43#define MIPI_CAL_STATUS_ACTIVE		(1 <<  0)
44
45#define MIPI_CAL_CONFIG_CSIA		0x05
46#define MIPI_CAL_CONFIG_CSIB		0x06
47#define MIPI_CAL_CONFIG_CSIC		0x07
48#define MIPI_CAL_CONFIG_CSID		0x08
49#define MIPI_CAL_CONFIG_CSIE		0x09
50#define MIPI_CAL_CONFIG_CSIF		0x0a
51#define MIPI_CAL_CONFIG_DSIA		0x0e
52#define MIPI_CAL_CONFIG_DSIB		0x0f
53#define MIPI_CAL_CONFIG_DSIC		0x10
54#define MIPI_CAL_CONFIG_DSID		0x11
55
56#define MIPI_CAL_CONFIG_DSIA_CLK	0x19
57#define MIPI_CAL_CONFIG_DSIB_CLK	0x1a
58#define MIPI_CAL_CONFIG_CSIAB_CLK	0x1b
59#define MIPI_CAL_CONFIG_DSIC_CLK	0x1c
60#define MIPI_CAL_CONFIG_CSICD_CLK	0x1c
61#define MIPI_CAL_CONFIG_DSID_CLK	0x1d
62#define MIPI_CAL_CONFIG_CSIE_CLK	0x1d
63
64/* for data and clock lanes */
65#define MIPI_CAL_CONFIG_SELECT		(1 << 21)
66
67/* for data lanes */
68#define MIPI_CAL_CONFIG_HSPDOS(x)	(((x) & 0x1f) << 16)
69#define MIPI_CAL_CONFIG_HSPUOS(x)	(((x) & 0x1f) <<  8)
70#define MIPI_CAL_CONFIG_TERMOS(x)	(((x) & 0x1f) <<  0)
71
72/* for clock lanes */
73#define MIPI_CAL_CONFIG_HSCLKPDOSD(x)	(((x) & 0x1f) <<  8)
74#define MIPI_CAL_CONFIG_HSCLKPUOSD(x)	(((x) & 0x1f) <<  0)
75
76#define MIPI_CAL_BIAS_PAD_CFG0		0x16
77#define MIPI_CAL_BIAS_PAD_PDVCLAMP	(1 << 1)
78#define MIPI_CAL_BIAS_PAD_E_VCLAMP_REF	(1 << 0)
79
80#define MIPI_CAL_BIAS_PAD_CFG1		0x17
81#define MIPI_CAL_BIAS_PAD_DRV_DN_REF(x) (((x) & 0x7) << 16)
82#define MIPI_CAL_BIAS_PAD_DRV_UP_REF(x) (((x) & 0x7) << 8)
83
84#define MIPI_CAL_BIAS_PAD_CFG2		0x18
85#define MIPI_CAL_BIAS_PAD_VCLAMP(x)	(((x) & 0x7) << 16)
86#define MIPI_CAL_BIAS_PAD_VAUXP(x)	(((x) & 0x7) << 4)
87#define MIPI_CAL_BIAS_PAD_PDVREG	(1 << 1)
88
89struct tegra_mipi_pad {
90	unsigned long data;
91	unsigned long clk;
92};
93
94struct tegra_mipi_soc {
95	bool has_clk_lane;
96	const struct tegra_mipi_pad *pads;
97	unsigned int num_pads;
98
99	bool clock_enable_override;
100	bool needs_vclamp_ref;
101
102	/* bias pad configuration settings */
103	u8 pad_drive_down_ref;
104	u8 pad_drive_up_ref;
105
106	u8 pad_vclamp_level;
107	u8 pad_vauxp_level;
108
109	/* calibration settings for data lanes */
110	u8 hspdos;
111	u8 hspuos;
112	u8 termos;
113
114	/* calibration settings for clock lanes */
115	u8 hsclkpdos;
116	u8 hsclkpuos;
117};
118
119struct tegra_mipi {
120	const struct tegra_mipi_soc *soc;
121	struct device *dev;
122	void __iomem *regs;
123	struct mutex lock;
124	struct clk *clk;
125
126	unsigned long usage_count;
127};
128
129struct tegra_mipi_device {
130	struct platform_device *pdev;
131	struct tegra_mipi *mipi;
132	struct device *device;
133	unsigned long pads;
134};
135
136static inline u32 tegra_mipi_readl(struct tegra_mipi *mipi,
137				   unsigned long offset)
138{
139	return readl(mipi->regs + (offset << 2));
140}
141
142static inline void tegra_mipi_writel(struct tegra_mipi *mipi, u32 value,
143				     unsigned long offset)
144{
145	writel(value, mipi->regs + (offset << 2));
146}
147
148static int tegra_mipi_power_up(struct tegra_mipi *mipi)
149{
150	u32 value;
151	int err;
152
153	err = clk_enable(mipi->clk);
154	if (err < 0)
155		return err;
156
157	value = tegra_mipi_readl(mipi, MIPI_CAL_BIAS_PAD_CFG0);
158	value &= ~MIPI_CAL_BIAS_PAD_PDVCLAMP;
159
160	if (mipi->soc->needs_vclamp_ref)
161		value |= MIPI_CAL_BIAS_PAD_E_VCLAMP_REF;
162
163	tegra_mipi_writel(mipi, value, MIPI_CAL_BIAS_PAD_CFG0);
164
165	value = tegra_mipi_readl(mipi, MIPI_CAL_BIAS_PAD_CFG2);
166	value &= ~MIPI_CAL_BIAS_PAD_PDVREG;
167	tegra_mipi_writel(mipi, value, MIPI_CAL_BIAS_PAD_CFG2);
168
169	clk_disable(mipi->clk);
170
171	return 0;
172}
173
174static int tegra_mipi_power_down(struct tegra_mipi *mipi)
175{
176	u32 value;
177	int err;
178
179	err = clk_enable(mipi->clk);
180	if (err < 0)
181		return err;
182
183	/*
184	 * The MIPI_CAL_BIAS_PAD_PDVREG controls a voltage regulator that
185	 * supplies the DSI pads. This must be kept enabled until none of the
186	 * DSI lanes are used anymore.
187	 */
188	value = tegra_mipi_readl(mipi, MIPI_CAL_BIAS_PAD_CFG2);
189	value |= MIPI_CAL_BIAS_PAD_PDVREG;
190	tegra_mipi_writel(mipi, value, MIPI_CAL_BIAS_PAD_CFG2);
191
192	/*
193	 * MIPI_CAL_BIAS_PAD_PDVCLAMP and MIPI_CAL_BIAS_PAD_E_VCLAMP_REF
194	 * control a regulator that supplies current to the pre-driver logic.
195	 * Powering down this regulator causes DSI to fail, so it must remain
196	 * powered on until none of the DSI lanes are used anymore.
197	 */
198	value = tegra_mipi_readl(mipi, MIPI_CAL_BIAS_PAD_CFG0);
199
200	if (mipi->soc->needs_vclamp_ref)
201		value &= ~MIPI_CAL_BIAS_PAD_E_VCLAMP_REF;
202
203	value |= MIPI_CAL_BIAS_PAD_PDVCLAMP;
204	tegra_mipi_writel(mipi, value, MIPI_CAL_BIAS_PAD_CFG0);
205
206	return 0;
207}
208
209struct tegra_mipi_device *tegra_mipi_request(struct device *device)
210{
211	struct device_node *np = device->of_node;
212	struct tegra_mipi_device *dev;
213	struct of_phandle_args args;
214	int err;
215
216	err = of_parse_phandle_with_args(np, "nvidia,mipi-calibrate",
217					 "#nvidia,mipi-calibrate-cells", 0,
218					 &args);
219	if (err < 0)
220		return ERR_PTR(err);
221
222	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
223	if (!dev) {
224		err = -ENOMEM;
225		goto out;
226	}
227
228	dev->pdev = of_find_device_by_node(args.np);
229	if (!dev->pdev) {
230		err = -ENODEV;
231		goto free;
232	}
233
234	dev->mipi = platform_get_drvdata(dev->pdev);
235	if (!dev->mipi) {
236		err = -EPROBE_DEFER;
237		goto put;
238	}
239
240	of_node_put(args.np);
241
242	dev->pads = args.args[0];
243	dev->device = device;
244
245	mutex_lock(&dev->mipi->lock);
246
247	if (dev->mipi->usage_count++ == 0) {
248		err = tegra_mipi_power_up(dev->mipi);
249		if (err < 0) {
250			dev_err(dev->mipi->dev,
251				"failed to power up MIPI bricks: %d\n",
252				err);
253			return ERR_PTR(err);
254		}
255	}
256
257	mutex_unlock(&dev->mipi->lock);
258
259	return dev;
260
261put:
262	platform_device_put(dev->pdev);
263free:
264	kfree(dev);
265out:
266	of_node_put(args.np);
267	return ERR_PTR(err);
268}
269EXPORT_SYMBOL(tegra_mipi_request);
270
271void tegra_mipi_free(struct tegra_mipi_device *device)
272{
273	int err;
274
275	mutex_lock(&device->mipi->lock);
276
277	if (--device->mipi->usage_count == 0) {
278		err = tegra_mipi_power_down(device->mipi);
279		if (err < 0) {
280			/*
281			 * Not much that can be done here, so an error message
282			 * will have to do.
283			 */
284			dev_err(device->mipi->dev,
285				"failed to power down MIPI bricks: %d\n",
286				err);
287		}
288	}
289
290	mutex_unlock(&device->mipi->lock);
291
292	platform_device_put(device->pdev);
293	kfree(device);
294}
295EXPORT_SYMBOL(tegra_mipi_free);
296
297static int tegra_mipi_wait(struct tegra_mipi *mipi)
298{
299	unsigned long timeout = jiffies + msecs_to_jiffies(250);
300	u32 value;
301
302	while (time_before(jiffies, timeout)) {
303		value = tegra_mipi_readl(mipi, MIPI_CAL_STATUS);
304		if ((value & MIPI_CAL_STATUS_ACTIVE) == 0 &&
305		    (value & MIPI_CAL_STATUS_DONE) != 0)
306			return 0;
307
308		usleep_range(10, 50);
309	}
310
311	return -ETIMEDOUT;
312}
313
314int tegra_mipi_calibrate(struct tegra_mipi_device *device)
315{
316	const struct tegra_mipi_soc *soc = device->mipi->soc;
317	unsigned int i;
318	u32 value;
319	int err;
320
321	err = clk_enable(device->mipi->clk);
322	if (err < 0)
323		return err;
324
325	mutex_lock(&device->mipi->lock);
326
327	value = MIPI_CAL_BIAS_PAD_DRV_DN_REF(soc->pad_drive_down_ref) |
328		MIPI_CAL_BIAS_PAD_DRV_UP_REF(soc->pad_drive_up_ref);
329	tegra_mipi_writel(device->mipi, value, MIPI_CAL_BIAS_PAD_CFG1);
330
331	value = tegra_mipi_readl(device->mipi, MIPI_CAL_BIAS_PAD_CFG2);
332	value &= ~MIPI_CAL_BIAS_PAD_VCLAMP(0x7);
333	value &= ~MIPI_CAL_BIAS_PAD_VAUXP(0x7);
334	value |= MIPI_CAL_BIAS_PAD_VCLAMP(soc->pad_vclamp_level);
335	value |= MIPI_CAL_BIAS_PAD_VAUXP(soc->pad_vauxp_level);
336	tegra_mipi_writel(device->mipi, value, MIPI_CAL_BIAS_PAD_CFG2);
337
338	for (i = 0; i < soc->num_pads; i++) {
339		u32 clk = 0, data = 0;
340
341		if (device->pads & BIT(i)) {
342			data = MIPI_CAL_CONFIG_SELECT |
343			       MIPI_CAL_CONFIG_HSPDOS(soc->hspdos) |
344			       MIPI_CAL_CONFIG_HSPUOS(soc->hspuos) |
345			       MIPI_CAL_CONFIG_TERMOS(soc->termos);
346			clk = MIPI_CAL_CONFIG_SELECT |
347			      MIPI_CAL_CONFIG_HSCLKPDOSD(soc->hsclkpdos) |
348			      MIPI_CAL_CONFIG_HSCLKPUOSD(soc->hsclkpuos);
349		}
350
351		tegra_mipi_writel(device->mipi, data, soc->pads[i].data);
352
353		if (soc->has_clk_lane && soc->pads[i].clk != 0)
354			tegra_mipi_writel(device->mipi, clk, soc->pads[i].clk);
355	}
356
357	value = tegra_mipi_readl(device->mipi, MIPI_CAL_CTRL);
358	value &= ~MIPI_CAL_CTRL_NOISE_FILTER(0xf);
359	value &= ~MIPI_CAL_CTRL_PRESCALE(0x3);
360	value |= MIPI_CAL_CTRL_NOISE_FILTER(0xa);
361	value |= MIPI_CAL_CTRL_PRESCALE(0x2);
362
363	if (!soc->clock_enable_override)
364		value &= ~MIPI_CAL_CTRL_CLKEN_OVR;
365	else
366		value |= MIPI_CAL_CTRL_CLKEN_OVR;
367
368	tegra_mipi_writel(device->mipi, value, MIPI_CAL_CTRL);
369
370	/* clear any pending status bits */
371	value = tegra_mipi_readl(device->mipi, MIPI_CAL_STATUS);
372	tegra_mipi_writel(device->mipi, value, MIPI_CAL_STATUS);
373
374	value = tegra_mipi_readl(device->mipi, MIPI_CAL_CTRL);
375	value |= MIPI_CAL_CTRL_START;
376	tegra_mipi_writel(device->mipi, value, MIPI_CAL_CTRL);
377
378	err = tegra_mipi_wait(device->mipi);
379
380	mutex_unlock(&device->mipi->lock);
381	clk_disable(device->mipi->clk);
382
383	return err;
384}
385EXPORT_SYMBOL(tegra_mipi_calibrate);
386
387static const struct tegra_mipi_pad tegra114_mipi_pads[] = {
388	{ .data = MIPI_CAL_CONFIG_CSIA },
389	{ .data = MIPI_CAL_CONFIG_CSIB },
390	{ .data = MIPI_CAL_CONFIG_CSIC },
391	{ .data = MIPI_CAL_CONFIG_CSID },
392	{ .data = MIPI_CAL_CONFIG_CSIE },
393	{ .data = MIPI_CAL_CONFIG_DSIA },
394	{ .data = MIPI_CAL_CONFIG_DSIB },
395	{ .data = MIPI_CAL_CONFIG_DSIC },
396	{ .data = MIPI_CAL_CONFIG_DSID },
397};
398
399static const struct tegra_mipi_soc tegra114_mipi_soc = {
400	.has_clk_lane = false,
401	.pads = tegra114_mipi_pads,
402	.num_pads = ARRAY_SIZE(tegra114_mipi_pads),
403	.clock_enable_override = true,
404	.needs_vclamp_ref = true,
405	.pad_drive_down_ref = 0x2,
406	.pad_drive_up_ref = 0x0,
407	.pad_vclamp_level = 0x0,
408	.pad_vauxp_level = 0x0,
409	.hspdos = 0x0,
410	.hspuos = 0x4,
411	.termos = 0x5,
412	.hsclkpdos = 0x0,
413	.hsclkpuos = 0x4,
414};
415
416static const struct tegra_mipi_pad tegra124_mipi_pads[] = {
417	{ .data = MIPI_CAL_CONFIG_CSIA, .clk = MIPI_CAL_CONFIG_CSIAB_CLK },
418	{ .data = MIPI_CAL_CONFIG_CSIB, .clk = MIPI_CAL_CONFIG_CSIAB_CLK },
419	{ .data = MIPI_CAL_CONFIG_CSIC, .clk = MIPI_CAL_CONFIG_CSICD_CLK },
420	{ .data = MIPI_CAL_CONFIG_CSID, .clk = MIPI_CAL_CONFIG_CSICD_CLK },
421	{ .data = MIPI_CAL_CONFIG_CSIE, .clk = MIPI_CAL_CONFIG_CSIE_CLK  },
422	{ .data = MIPI_CAL_CONFIG_DSIA, .clk = MIPI_CAL_CONFIG_DSIA_CLK  },
423	{ .data = MIPI_CAL_CONFIG_DSIB, .clk = MIPI_CAL_CONFIG_DSIB_CLK  },
424};
425
426static const struct tegra_mipi_soc tegra124_mipi_soc = {
427	.has_clk_lane = true,
428	.pads = tegra124_mipi_pads,
429	.num_pads = ARRAY_SIZE(tegra124_mipi_pads),
430	.clock_enable_override = true,
431	.needs_vclamp_ref = true,
432	.pad_drive_down_ref = 0x2,
433	.pad_drive_up_ref = 0x0,
434	.pad_vclamp_level = 0x0,
435	.pad_vauxp_level = 0x0,
436	.hspdos = 0x0,
437	.hspuos = 0x0,
438	.termos = 0x0,
439	.hsclkpdos = 0x1,
440	.hsclkpuos = 0x2,
441};
442
443static const struct tegra_mipi_soc tegra132_mipi_soc = {
444	.has_clk_lane = true,
445	.pads = tegra124_mipi_pads,
446	.num_pads = ARRAY_SIZE(tegra124_mipi_pads),
447	.clock_enable_override = false,
448	.needs_vclamp_ref = false,
449	.pad_drive_down_ref = 0x0,
450	.pad_drive_up_ref = 0x3,
451	.pad_vclamp_level = 0x0,
452	.pad_vauxp_level = 0x0,
453	.hspdos = 0x0,
454	.hspuos = 0x0,
455	.termos = 0x0,
456	.hsclkpdos = 0x3,
457	.hsclkpuos = 0x2,
458};
459
460static const struct tegra_mipi_pad tegra210_mipi_pads[] = {
461	{ .data = MIPI_CAL_CONFIG_CSIA, .clk = 0 },
462	{ .data = MIPI_CAL_CONFIG_CSIB, .clk = 0 },
463	{ .data = MIPI_CAL_CONFIG_CSIC, .clk = 0 },
464	{ .data = MIPI_CAL_CONFIG_CSID, .clk = 0 },
465	{ .data = MIPI_CAL_CONFIG_CSIE, .clk = 0 },
466	{ .data = MIPI_CAL_CONFIG_CSIF, .clk = 0 },
467	{ .data = MIPI_CAL_CONFIG_DSIA, .clk = MIPI_CAL_CONFIG_DSIA_CLK },
468	{ .data = MIPI_CAL_CONFIG_DSIB, .clk = MIPI_CAL_CONFIG_DSIB_CLK },
469	{ .data = MIPI_CAL_CONFIG_DSIC, .clk = MIPI_CAL_CONFIG_DSIC_CLK },
470	{ .data = MIPI_CAL_CONFIG_DSID, .clk = MIPI_CAL_CONFIG_DSID_CLK },
471};
472
473static const struct tegra_mipi_soc tegra210_mipi_soc = {
474	.has_clk_lane = true,
475	.pads = tegra210_mipi_pads,
476	.num_pads = ARRAY_SIZE(tegra210_mipi_pads),
477	.clock_enable_override = true,
478	.needs_vclamp_ref = false,
479	.pad_drive_down_ref = 0x0,
480	.pad_drive_up_ref = 0x3,
481	.pad_vclamp_level = 0x1,
482	.pad_vauxp_level = 0x1,
483	.hspdos = 0x0,
484	.hspuos = 0x2,
485	.termos = 0x0,
486	.hsclkpdos = 0x0,
487	.hsclkpuos = 0x2,
488};
489
490static const struct of_device_id tegra_mipi_of_match[] = {
491	{ .compatible = "nvidia,tegra114-mipi", .data = &tegra114_mipi_soc },
492	{ .compatible = "nvidia,tegra124-mipi", .data = &tegra124_mipi_soc },
493	{ .compatible = "nvidia,tegra132-mipi", .data = &tegra132_mipi_soc },
494	{ .compatible = "nvidia,tegra210-mipi", .data = &tegra210_mipi_soc },
495	{ },
496};
497
498static int tegra_mipi_probe(struct platform_device *pdev)
499{
500	const struct of_device_id *match;
501	struct tegra_mipi *mipi;
502	struct resource *res;
503	int err;
504
505	match = of_match_node(tegra_mipi_of_match, pdev->dev.of_node);
506	if (!match)
507		return -ENODEV;
508
509	mipi = devm_kzalloc(&pdev->dev, sizeof(*mipi), GFP_KERNEL);
510	if (!mipi)
511		return -ENOMEM;
512
513	mipi->soc = match->data;
514	mipi->dev = &pdev->dev;
515
516	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
517	mipi->regs = devm_ioremap_resource(&pdev->dev, res);
518	if (IS_ERR(mipi->regs))
519		return PTR_ERR(mipi->regs);
520
521	mutex_init(&mipi->lock);
522
523	mipi->clk = devm_clk_get(&pdev->dev, NULL);
524	if (IS_ERR(mipi->clk)) {
525		dev_err(&pdev->dev, "failed to get clock\n");
526		return PTR_ERR(mipi->clk);
527	}
528
529	err = clk_prepare(mipi->clk);
530	if (err < 0)
531		return err;
532
533	platform_set_drvdata(pdev, mipi);
534
535	return 0;
536}
537
538static int tegra_mipi_remove(struct platform_device *pdev)
539{
540	struct tegra_mipi *mipi = platform_get_drvdata(pdev);
541
542	clk_unprepare(mipi->clk);
543
544	return 0;
545}
546
547struct platform_driver tegra_mipi_driver = {
548	.driver = {
549		.name = "tegra-mipi",
550		.of_match_table = tegra_mipi_of_match,
551	},
552	.probe = tegra_mipi_probe,
553	.remove = tegra_mipi_remove,
554};
555