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/host1x.h>
25#include <linux/io.h>
26#include <linux/iopoll.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					     struct device_node *np)
211{
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	return dev;
246
247put:
248	platform_device_put(dev->pdev);
249free:
250	kfree(dev);
251out:
252	of_node_put(args.np);
253	return ERR_PTR(err);
254}
255EXPORT_SYMBOL(tegra_mipi_request);
256
257void tegra_mipi_free(struct tegra_mipi_device *device)
258{
259	platform_device_put(device->pdev);
260	kfree(device);
261}
262EXPORT_SYMBOL(tegra_mipi_free);
263
264int tegra_mipi_enable(struct tegra_mipi_device *dev)
265{
266	int err = 0;
267
268	mutex_lock(&dev->mipi->lock);
269
270	if (dev->mipi->usage_count++ == 0)
271		err = tegra_mipi_power_up(dev->mipi);
272
273	mutex_unlock(&dev->mipi->lock);
274
275	return err;
276
277}
278EXPORT_SYMBOL(tegra_mipi_enable);
279
280int tegra_mipi_disable(struct tegra_mipi_device *dev)
281{
282	int err = 0;
283
284	mutex_lock(&dev->mipi->lock);
285
286	if (--dev->mipi->usage_count == 0)
287		err = tegra_mipi_power_down(dev->mipi);
288
289	mutex_unlock(&dev->mipi->lock);
290
291	return err;
292
293}
294EXPORT_SYMBOL(tegra_mipi_disable);
295
296int tegra_mipi_finish_calibration(struct tegra_mipi_device *device)
297{
298	struct tegra_mipi *mipi = device->mipi;
299	void __iomem *status_reg = mipi->regs + (MIPI_CAL_STATUS << 2);
300	u32 value;
301	int err;
302
303	err = readl_relaxed_poll_timeout(status_reg, value,
304					 !(value & MIPI_CAL_STATUS_ACTIVE) &&
305					 (value & MIPI_CAL_STATUS_DONE), 50,
306					 250000);
307	mutex_unlock(&device->mipi->lock);
308	clk_disable(device->mipi->clk);
309
310	return err;
311}
312EXPORT_SYMBOL(tegra_mipi_finish_calibration);
313
314int tegra_mipi_start_calibration(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	/*
379	 * Wait for min 72uS to let calibration logic finish calibration
380	 * sequence codes before waiting for pads idle state to apply the
381	 * results.
382	 */
383	usleep_range(75, 80);
384
385	return 0;
386}
387EXPORT_SYMBOL(tegra_mipi_start_calibration);
388
389static const struct tegra_mipi_pad tegra114_mipi_pads[] = {
390	{ .data = MIPI_CAL_CONFIG_CSIA },
391	{ .data = MIPI_CAL_CONFIG_CSIB },
392	{ .data = MIPI_CAL_CONFIG_CSIC },
393	{ .data = MIPI_CAL_CONFIG_CSID },
394	{ .data = MIPI_CAL_CONFIG_CSIE },
395	{ .data = MIPI_CAL_CONFIG_DSIA },
396	{ .data = MIPI_CAL_CONFIG_DSIB },
397	{ .data = MIPI_CAL_CONFIG_DSIC },
398	{ .data = MIPI_CAL_CONFIG_DSID },
399};
400
401static const struct tegra_mipi_soc tegra114_mipi_soc = {
402	.has_clk_lane = false,
403	.pads = tegra114_mipi_pads,
404	.num_pads = ARRAY_SIZE(tegra114_mipi_pads),
405	.clock_enable_override = true,
406	.needs_vclamp_ref = true,
407	.pad_drive_down_ref = 0x2,
408	.pad_drive_up_ref = 0x0,
409	.pad_vclamp_level = 0x0,
410	.pad_vauxp_level = 0x0,
411	.hspdos = 0x0,
412	.hspuos = 0x4,
413	.termos = 0x5,
414	.hsclkpdos = 0x0,
415	.hsclkpuos = 0x4,
416};
417
418static const struct tegra_mipi_pad tegra124_mipi_pads[] = {
419	{ .data = MIPI_CAL_CONFIG_CSIA, .clk = MIPI_CAL_CONFIG_CSIAB_CLK },
420	{ .data = MIPI_CAL_CONFIG_CSIB, .clk = MIPI_CAL_CONFIG_CSIAB_CLK },
421	{ .data = MIPI_CAL_CONFIG_CSIC, .clk = MIPI_CAL_CONFIG_CSICD_CLK },
422	{ .data = MIPI_CAL_CONFIG_CSID, .clk = MIPI_CAL_CONFIG_CSICD_CLK },
423	{ .data = MIPI_CAL_CONFIG_CSIE, .clk = MIPI_CAL_CONFIG_CSIE_CLK  },
424	{ .data = MIPI_CAL_CONFIG_DSIA, .clk = MIPI_CAL_CONFIG_DSIA_CLK  },
425	{ .data = MIPI_CAL_CONFIG_DSIB, .clk = MIPI_CAL_CONFIG_DSIB_CLK  },
426};
427
428static const struct tegra_mipi_soc tegra124_mipi_soc = {
429	.has_clk_lane = true,
430	.pads = tegra124_mipi_pads,
431	.num_pads = ARRAY_SIZE(tegra124_mipi_pads),
432	.clock_enable_override = true,
433	.needs_vclamp_ref = true,
434	.pad_drive_down_ref = 0x2,
435	.pad_drive_up_ref = 0x0,
436	.pad_vclamp_level = 0x0,
437	.pad_vauxp_level = 0x0,
438	.hspdos = 0x0,
439	.hspuos = 0x0,
440	.termos = 0x0,
441	.hsclkpdos = 0x1,
442	.hsclkpuos = 0x2,
443};
444
445static const struct tegra_mipi_soc tegra132_mipi_soc = {
446	.has_clk_lane = true,
447	.pads = tegra124_mipi_pads,
448	.num_pads = ARRAY_SIZE(tegra124_mipi_pads),
449	.clock_enable_override = false,
450	.needs_vclamp_ref = false,
451	.pad_drive_down_ref = 0x0,
452	.pad_drive_up_ref = 0x3,
453	.pad_vclamp_level = 0x0,
454	.pad_vauxp_level = 0x0,
455	.hspdos = 0x0,
456	.hspuos = 0x0,
457	.termos = 0x0,
458	.hsclkpdos = 0x3,
459	.hsclkpuos = 0x2,
460};
461
462static const struct tegra_mipi_pad tegra210_mipi_pads[] = {
463	{ .data = MIPI_CAL_CONFIG_CSIA, .clk = 0 },
464	{ .data = MIPI_CAL_CONFIG_CSIB, .clk = 0 },
465	{ .data = MIPI_CAL_CONFIG_CSIC, .clk = 0 },
466	{ .data = MIPI_CAL_CONFIG_CSID, .clk = 0 },
467	{ .data = MIPI_CAL_CONFIG_CSIE, .clk = 0 },
468	{ .data = MIPI_CAL_CONFIG_CSIF, .clk = 0 },
469	{ .data = MIPI_CAL_CONFIG_DSIA, .clk = MIPI_CAL_CONFIG_DSIA_CLK },
470	{ .data = MIPI_CAL_CONFIG_DSIB, .clk = MIPI_CAL_CONFIG_DSIB_CLK },
471	{ .data = MIPI_CAL_CONFIG_DSIC, .clk = MIPI_CAL_CONFIG_DSIC_CLK },
472	{ .data = MIPI_CAL_CONFIG_DSID, .clk = MIPI_CAL_CONFIG_DSID_CLK },
473};
474
475static const struct tegra_mipi_soc tegra210_mipi_soc = {
476	.has_clk_lane = true,
477	.pads = tegra210_mipi_pads,
478	.num_pads = ARRAY_SIZE(tegra210_mipi_pads),
479	.clock_enable_override = true,
480	.needs_vclamp_ref = false,
481	.pad_drive_down_ref = 0x0,
482	.pad_drive_up_ref = 0x3,
483	.pad_vclamp_level = 0x1,
484	.pad_vauxp_level = 0x1,
485	.hspdos = 0x0,
486	.hspuos = 0x2,
487	.termos = 0x0,
488	.hsclkpdos = 0x0,
489	.hsclkpuos = 0x2,
490};
491
492static const struct of_device_id tegra_mipi_of_match[] = {
493	{ .compatible = "nvidia,tegra114-mipi", .data = &tegra114_mipi_soc },
494	{ .compatible = "nvidia,tegra124-mipi", .data = &tegra124_mipi_soc },
495	{ .compatible = "nvidia,tegra132-mipi", .data = &tegra132_mipi_soc },
496	{ .compatible = "nvidia,tegra210-mipi", .data = &tegra210_mipi_soc },
497	{ },
498};
499
500static int tegra_mipi_probe(struct platform_device *pdev)
501{
502	const struct of_device_id *match;
503	struct tegra_mipi *mipi;
504	int err;
505
506	match = of_match_node(tegra_mipi_of_match, pdev->dev.of_node);
507	if (!match)
508		return -ENODEV;
509
510	mipi = devm_kzalloc(&pdev->dev, sizeof(*mipi), GFP_KERNEL);
511	if (!mipi)
512		return -ENOMEM;
513
514	mipi->soc = match->data;
515	mipi->dev = &pdev->dev;
516
517	mipi->regs = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
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