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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Intel Sunrisepoint LPSS core support.
  4 *
  5 * Copyright (C) 2015, Intel Corporation
  6 *
  7 * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
  8 *          Mika Westerberg <mika.westerberg@linux.intel.com>
  9 *          Heikki Krogerus <heikki.krogerus@linux.intel.com>
 10 *          Jarkko Nikula <jarkko.nikula@linux.intel.com>
 11 */
 12
 13#include <linux/array_size.h>
 14#include <linux/bits.h>
 15#include <linux/clkdev.h>
 16#include <linux/clk.h>
 17#include <linux/clk-provider.h>
 18#include <linux/debugfs.h>
 19#include <linux/device.h>
 20#include <linux/err.h>
 21#include <linux/gfp_types.h>
 22#include <linux/idr.h>
 23#include <linux/io.h>
 24#include <linux/ioport.h>
 25#include <linux/mfd/core.h>
 26#include <linux/module.h>
 27#include <linux/pm.h>
 28#include <linux/pm_qos.h>
 29#include <linux/pm_runtime.h>
 30#include <linux/sprintf.h>
 31#include <linux/types.h>
 32
 33#include <linux/io-64-nonatomic-lo-hi.h>
 34
 35#include <linux/dma/idma64.h>
 36
 37#include "intel-lpss.h"
 38
 39struct dentry;
 40
 41#define LPSS_DEV_OFFSET		0x000
 42#define LPSS_DEV_SIZE		0x200
 43#define LPSS_PRIV_OFFSET	0x200
 44#define LPSS_PRIV_SIZE		0x100
 45#define LPSS_PRIV_REG_COUNT	(LPSS_PRIV_SIZE / 4)
 46#define LPSS_IDMA64_OFFSET	0x800
 47#define LPSS_IDMA64_SIZE	0x800
 48
 49/* Offsets from lpss->priv */
 50#define LPSS_PRIV_RESETS		0x04
 51#define LPSS_PRIV_RESETS_IDMA		BIT(2)
 52#define LPSS_PRIV_RESETS_FUNC		0x3
 53
 54#define LPSS_PRIV_ACTIVELTR		0x10
 55#define LPSS_PRIV_IDLELTR		0x14
 56
 57#define LPSS_PRIV_LTR_REQ		BIT(15)
 58#define LPSS_PRIV_LTR_SCALE_MASK	GENMASK(11, 10)
 59#define LPSS_PRIV_LTR_SCALE_1US		(2 << 10)
 60#define LPSS_PRIV_LTR_SCALE_32US	(3 << 10)
 61#define LPSS_PRIV_LTR_VALUE_MASK	GENMASK(9, 0)
 62
 63#define LPSS_PRIV_SSP_REG		0x20
 64#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN	BIT(0)
 65
 66#define LPSS_PRIV_REMAP_ADDR		0x40
 67
 68#define LPSS_PRIV_CAPS			0xfc
 69#define LPSS_PRIV_CAPS_NO_IDMA		BIT(8)
 70#define LPSS_PRIV_CAPS_TYPE_MASK	GENMASK(7, 4)
 71#define LPSS_PRIV_CAPS_TYPE_SHIFT	4
 72
 73/* This matches the type field in CAPS register */
 74enum intel_lpss_dev_type {
 75	LPSS_DEV_I2C = 0,
 76	LPSS_DEV_UART,
 77	LPSS_DEV_SPI,
 78};
 79
 80struct intel_lpss {
 81	const struct intel_lpss_platform_info *info;
 82	enum intel_lpss_dev_type type;
 83	struct clk *clk;
 84	struct clk_lookup *clock;
 85	struct mfd_cell *cell;
 86	struct device *dev;
 87	void __iomem *priv;
 88	u32 priv_ctx[LPSS_PRIV_REG_COUNT];
 89	int devid;
 90	u32 caps;
 91	u32 active_ltr;
 92	u32 idle_ltr;
 93	struct dentry *debugfs;
 94};
 95
 96static const struct resource intel_lpss_dev_resources[] = {
 97	DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
 98	DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
 99	DEFINE_RES_IRQ(0),
100};
101
102static const struct resource intel_lpss_idma64_resources[] = {
103	DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
104	DEFINE_RES_IRQ(0),
105};
106
107/*
108 * Cells needs to be ordered so that the iDMA is created first. This is
109 * because we need to be sure the DMA is available when the host controller
110 * driver is probed.
111 */
112static const struct mfd_cell intel_lpss_idma64_cell = {
113	.name = LPSS_IDMA64_DRIVER_NAME,
114	.num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
115	.resources = intel_lpss_idma64_resources,
116};
117
118static const struct mfd_cell intel_lpss_i2c_cell = {
119	.name = "i2c_designware",
120	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
121	.resources = intel_lpss_dev_resources,
122};
123
124static const struct mfd_cell intel_lpss_uart_cell = {
125	.name = "dw-apb-uart",
126	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
127	.resources = intel_lpss_dev_resources,
128};
129
130static const struct mfd_cell intel_lpss_spi_cell = {
131	.name = "pxa2xx-spi",
132	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
133	.resources = intel_lpss_dev_resources,
134};
135
136static DEFINE_IDA(intel_lpss_devid_ida);
137static struct dentry *intel_lpss_debugfs;
138
139static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
140{
141	lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
142	lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
143}
144
145static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
146{
147	struct dentry *dir;
148
149	dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
150	if (IS_ERR(dir))
151		return PTR_ERR(dir);
152
153	/* Cache the values into lpss structure */
154	intel_lpss_cache_ltr(lpss);
155
156	debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
157	debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
158	debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
159
160	lpss->debugfs = dir;
161	return 0;
162}
163
164static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
165{
166	debugfs_remove_recursive(lpss->debugfs);
167}
168
169static void intel_lpss_ltr_set(struct device *dev, s32 val)
170{
171	struct intel_lpss *lpss = dev_get_drvdata(dev);
172	u32 ltr;
173
174	/*
175	 * Program latency tolerance (LTR) accordingly what has been asked
176	 * by the PM QoS layer or disable it in case we were passed
177	 * negative value or PM_QOS_LATENCY_ANY.
178	 */
179	ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
180
181	if (val == PM_QOS_LATENCY_ANY || val < 0) {
182		ltr &= ~LPSS_PRIV_LTR_REQ;
183	} else {
184		ltr |= LPSS_PRIV_LTR_REQ;
185		ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
186		ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
187
188		if (val > LPSS_PRIV_LTR_VALUE_MASK)
189			ltr |= LPSS_PRIV_LTR_SCALE_32US | val >> 5;
190		else
191			ltr |= LPSS_PRIV_LTR_SCALE_1US | val;
192	}
193
194	if (ltr == lpss->active_ltr)
195		return;
196
197	writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
198	writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
199
200	/* Cache the values into lpss structure */
201	intel_lpss_cache_ltr(lpss);
202}
203
204static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
205{
206	lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
207	dev_pm_qos_expose_latency_tolerance(lpss->dev);
208}
209
210static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
211{
212	dev_pm_qos_hide_latency_tolerance(lpss->dev);
213	lpss->dev->power.set_latency_tolerance = NULL;
214}
215
216static int intel_lpss_assign_devs(struct intel_lpss *lpss)
217{
218	const struct mfd_cell *cell;
219	unsigned int type;
220
221	type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
222	type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
223
224	switch (type) {
225	case LPSS_DEV_I2C:
226		cell = &intel_lpss_i2c_cell;
227		break;
228	case LPSS_DEV_UART:
229		cell = &intel_lpss_uart_cell;
230		break;
231	case LPSS_DEV_SPI:
232		cell = &intel_lpss_spi_cell;
233		break;
234	default:
235		return -ENODEV;
236	}
237
238	lpss->cell = devm_kmemdup(lpss->dev, cell, sizeof(*cell), GFP_KERNEL);
239	if (!lpss->cell)
240		return -ENOMEM;
241
242	lpss->type = type;
243
244	return 0;
245}
246
247static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
248{
249	return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
250}
251
252static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
253{
254	resource_size_t addr = lpss->info->mem->start;
255
256	lo_hi_writeq(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR);
257}
258
259static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
260{
261	u32 value = LPSS_PRIV_RESETS_FUNC | LPSS_PRIV_RESETS_IDMA;
262
263	/* Bring out the device from reset */
264	writel(value, lpss->priv + LPSS_PRIV_RESETS);
265}
266
267static void intel_lpss_init_dev(const struct intel_lpss *lpss)
268{
269	u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
270
271	/* Set the device in reset state */
272	writel(0, lpss->priv + LPSS_PRIV_RESETS);
273
274	intel_lpss_deassert_reset(lpss);
275
276	intel_lpss_set_remap_addr(lpss);
277
278	if (!intel_lpss_has_idma(lpss))
279		return;
280
281	/* Make sure that SPI multiblock DMA transfers are re-enabled */
282	if (lpss->type == LPSS_DEV_SPI)
283		writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
284}
285
286static void intel_lpss_unregister_clock_tree(struct clk *clk)
287{
288	struct clk *parent;
289
290	while (clk) {
291		parent = clk_get_parent(clk);
292		clk_unregister(clk);
293		clk = parent;
294	}
295}
296
297static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
298					     const char *devname,
299					     struct clk **clk)
300{
301	char name[32];
302	struct clk *tmp = *clk;
303	int ret;
304
305	snprintf(name, sizeof(name), "%s-enable", devname);
306	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
307				lpss->priv, 0, 0, NULL);
308	if (IS_ERR(tmp))
309		return PTR_ERR(tmp);
310
311	snprintf(name, sizeof(name), "%s-div", devname);
312	tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
313					      0, lpss->priv, 1, 15, 16, 15,
314					      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
315					      NULL);
316	if (IS_ERR(tmp))
317		return PTR_ERR(tmp);
318	*clk = tmp;
319
320	if (lpss->info->quirks & QUIRK_CLOCK_DIVIDER_UNITY) {
321		ret = clk_set_rate(tmp, lpss->info->clk_rate);
322		if (ret)
323			return ret;
324	}
325
326	snprintf(name, sizeof(name), "%s-update", devname);
327	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
328				CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
329	if (IS_ERR(tmp))
330		return PTR_ERR(tmp);
331	*clk = tmp;
332
333	return 0;
334}
335
336static int intel_lpss_register_clock(struct intel_lpss *lpss)
337{
338	const struct mfd_cell *cell = lpss->cell;
339	struct clk *clk;
340	char devname[24];
341	int ret;
342
343	if (!lpss->info->clk_rate)
344		return 0;
345
346	/* Root clock */
347	clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL, 0,
348				      lpss->info->clk_rate);
349	if (IS_ERR(clk))
350		return PTR_ERR(clk);
351
352	snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
353
354	/*
355	 * Support for clock divider only if it has some preset value.
356	 * Otherwise we assume that the divider is not used.
357	 */
358	if (lpss->type != LPSS_DEV_I2C) {
359		ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
360		if (ret)
361			goto err_clk_register;
362	}
363
364	ret = -ENOMEM;
365
366	/* Clock for the host controller */
367	lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
368	if (!lpss->clock)
369		goto err_clk_register;
370
371	lpss->clk = clk;
372
373	return 0;
374
375err_clk_register:
376	intel_lpss_unregister_clock_tree(clk);
377
378	return ret;
379}
380
381static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
382{
383	if (IS_ERR_OR_NULL(lpss->clk))
384		return;
385
386	clkdev_drop(lpss->clock);
387	intel_lpss_unregister_clock_tree(lpss->clk);
388}
389
390int intel_lpss_probe(struct device *dev,
391		     const struct intel_lpss_platform_info *info)
392{
393	struct intel_lpss *lpss;
394	int ret;
395
396	if (!info || !info->mem)
397		return -EINVAL;
398
399	if (info->irq < 0)
400		return info->irq;
401
402	lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
403	if (!lpss)
404		return -ENOMEM;
405
406	lpss->priv = devm_ioremap_uc(dev, info->mem->start + LPSS_PRIV_OFFSET,
407				  LPSS_PRIV_SIZE);
408	if (!lpss->priv)
409		return -ENOMEM;
410
411	lpss->info = info;
412	lpss->dev = dev;
413	lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
414
415	dev_set_drvdata(dev, lpss);
416
417	ret = intel_lpss_assign_devs(lpss);
418	if (ret)
419		return ret;
420
421	lpss->cell->swnode = info->swnode;
422	lpss->cell->ignore_resource_conflicts = info->quirks & QUIRK_IGNORE_RESOURCE_CONFLICTS;
423
424	intel_lpss_init_dev(lpss);
425
426	lpss->devid = ida_alloc(&intel_lpss_devid_ida, GFP_KERNEL);
427	if (lpss->devid < 0)
428		return lpss->devid;
429
430	ret = intel_lpss_register_clock(lpss);
431	if (ret)
432		goto err_clk_register;
433
434	intel_lpss_ltr_expose(lpss);
435
436	ret = intel_lpss_debugfs_add(lpss);
437	if (ret)
438		dev_warn(dev, "Failed to create debugfs entries\n");
439
440	if (intel_lpss_has_idma(lpss)) {
441		ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
442				      1, info->mem, info->irq, NULL);
443		if (ret)
444			dev_warn(dev, "Failed to add %s, fallback to PIO\n",
445				 LPSS_IDMA64_DRIVER_NAME);
446	}
447
448	ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
449			      1, info->mem, info->irq, NULL);
450	if (ret)
451		goto err_remove_ltr;
452
453	dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
454
455	return 0;
456
457err_remove_ltr:
458	intel_lpss_debugfs_remove(lpss);
459	intel_lpss_ltr_hide(lpss);
460	intel_lpss_unregister_clock(lpss);
461
462err_clk_register:
463	ida_free(&intel_lpss_devid_ida, lpss->devid);
464
465	return ret;
466}
467EXPORT_SYMBOL_NS_GPL(intel_lpss_probe, "INTEL_LPSS");
468
469void intel_lpss_remove(struct device *dev)
470{
471	struct intel_lpss *lpss = dev_get_drvdata(dev);
472
473	mfd_remove_devices(dev);
474	intel_lpss_debugfs_remove(lpss);
475	intel_lpss_ltr_hide(lpss);
476	intel_lpss_unregister_clock(lpss);
477	ida_free(&intel_lpss_devid_ida, lpss->devid);
478}
479EXPORT_SYMBOL_NS_GPL(intel_lpss_remove, "INTEL_LPSS");
480
481static int resume_lpss_device(struct device *dev, void *data)
482{
483	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND))
484		pm_runtime_resume(dev);
485
486	return 0;
487}
488
489static int intel_lpss_prepare(struct device *dev)
490{
491	/*
492	 * Resume both child devices before entering system sleep. This
493	 * ensures that they are in proper state before they get suspended.
494	 */
495	device_for_each_child_reverse(dev, NULL, resume_lpss_device);
496	return 0;
497}
498
499static int intel_lpss_suspend(struct device *dev)
500{
501	struct intel_lpss *lpss = dev_get_drvdata(dev);
502	unsigned int i;
503
504	/* Save device context */
505	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
506		lpss->priv_ctx[i] = readl(lpss->priv + i * 4);
507
508	/*
509	 * If the device type is not UART, then put the controller into
510	 * reset. UART cannot be put into reset since S3/S0ix fail when
511	 * no_console_suspend flag is enabled.
512	 */
513	if (lpss->type != LPSS_DEV_UART)
514		writel(0, lpss->priv + LPSS_PRIV_RESETS);
515
516	return 0;
517}
518
519static int intel_lpss_resume(struct device *dev)
520{
521	struct intel_lpss *lpss = dev_get_drvdata(dev);
522	unsigned int i;
523
524	intel_lpss_deassert_reset(lpss);
525
526	/* Restore device context */
527	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
528		writel(lpss->priv_ctx[i], lpss->priv + i * 4);
529
530	return 0;
531}
532
533EXPORT_NS_GPL_DEV_PM_OPS(intel_lpss_pm_ops, INTEL_LPSS) = {
534	.prepare = pm_sleep_ptr(&intel_lpss_prepare),
535	LATE_SYSTEM_SLEEP_PM_OPS(intel_lpss_suspend, intel_lpss_resume)
536	RUNTIME_PM_OPS(intel_lpss_suspend, intel_lpss_resume, NULL)
537};
538
539static int __init intel_lpss_init(void)
540{
541	intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
542	return 0;
543}
544module_init(intel_lpss_init);
545
546static void __exit intel_lpss_exit(void)
547{
548	ida_destroy(&intel_lpss_devid_ida);
549	debugfs_remove(intel_lpss_debugfs);
550}
551module_exit(intel_lpss_exit);
552
553MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
554MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
555MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
556MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
557MODULE_DESCRIPTION("Intel LPSS core driver");
558MODULE_LICENSE("GPL v2");
559/*
560 * Ensure the DMA driver is loaded before the host controller device appears,
561 * so that the host controller driver can request its DMA channels as early
562 * as possible.
563 *
564 * If the DMA module is not there that's OK as well.
565 */
566MODULE_SOFTDEP("pre: platform:" LPSS_IDMA64_DRIVER_NAME);
v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Intel Sunrisepoint LPSS core support.
  4 *
  5 * Copyright (C) 2015, Intel Corporation
  6 *
  7 * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
  8 *          Mika Westerberg <mika.westerberg@linux.intel.com>
  9 *          Heikki Krogerus <heikki.krogerus@linux.intel.com>
 10 *          Jarkko Nikula <jarkko.nikula@linux.intel.com>
 11 */
 12
 13#include <linux/array_size.h>
 14#include <linux/bits.h>
 15#include <linux/clkdev.h>
 16#include <linux/clk.h>
 17#include <linux/clk-provider.h>
 18#include <linux/debugfs.h>
 19#include <linux/device.h>
 20#include <linux/err.h>
 21#include <linux/gfp_types.h>
 22#include <linux/idr.h>
 23#include <linux/io.h>
 24#include <linux/ioport.h>
 25#include <linux/mfd/core.h>
 26#include <linux/module.h>
 27#include <linux/pm.h>
 28#include <linux/pm_qos.h>
 29#include <linux/pm_runtime.h>
 30#include <linux/sprintf.h>
 31#include <linux/types.h>
 32
 33#include <linux/io-64-nonatomic-lo-hi.h>
 34
 35#include <linux/dma/idma64.h>
 36
 37#include "intel-lpss.h"
 38
 39struct dentry;
 40
 41#define LPSS_DEV_OFFSET		0x000
 42#define LPSS_DEV_SIZE		0x200
 43#define LPSS_PRIV_OFFSET	0x200
 44#define LPSS_PRIV_SIZE		0x100
 45#define LPSS_PRIV_REG_COUNT	(LPSS_PRIV_SIZE / 4)
 46#define LPSS_IDMA64_OFFSET	0x800
 47#define LPSS_IDMA64_SIZE	0x800
 48
 49/* Offsets from lpss->priv */
 50#define LPSS_PRIV_RESETS		0x04
 51#define LPSS_PRIV_RESETS_IDMA		BIT(2)
 52#define LPSS_PRIV_RESETS_FUNC		0x3
 53
 54#define LPSS_PRIV_ACTIVELTR		0x10
 55#define LPSS_PRIV_IDLELTR		0x14
 56
 57#define LPSS_PRIV_LTR_REQ		BIT(15)
 58#define LPSS_PRIV_LTR_SCALE_MASK	GENMASK(11, 10)
 59#define LPSS_PRIV_LTR_SCALE_1US		(2 << 10)
 60#define LPSS_PRIV_LTR_SCALE_32US	(3 << 10)
 61#define LPSS_PRIV_LTR_VALUE_MASK	GENMASK(9, 0)
 62
 63#define LPSS_PRIV_SSP_REG		0x20
 64#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN	BIT(0)
 65
 66#define LPSS_PRIV_REMAP_ADDR		0x40
 67
 68#define LPSS_PRIV_CAPS			0xfc
 69#define LPSS_PRIV_CAPS_NO_IDMA		BIT(8)
 70#define LPSS_PRIV_CAPS_TYPE_MASK	GENMASK(7, 4)
 71#define LPSS_PRIV_CAPS_TYPE_SHIFT	4
 72
 73/* This matches the type field in CAPS register */
 74enum intel_lpss_dev_type {
 75	LPSS_DEV_I2C = 0,
 76	LPSS_DEV_UART,
 77	LPSS_DEV_SPI,
 78};
 79
 80struct intel_lpss {
 81	const struct intel_lpss_platform_info *info;
 82	enum intel_lpss_dev_type type;
 83	struct clk *clk;
 84	struct clk_lookup *clock;
 85	struct mfd_cell *cell;
 86	struct device *dev;
 87	void __iomem *priv;
 88	u32 priv_ctx[LPSS_PRIV_REG_COUNT];
 89	int devid;
 90	u32 caps;
 91	u32 active_ltr;
 92	u32 idle_ltr;
 93	struct dentry *debugfs;
 94};
 95
 96static const struct resource intel_lpss_dev_resources[] = {
 97	DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
 98	DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
 99	DEFINE_RES_IRQ(0),
100};
101
102static const struct resource intel_lpss_idma64_resources[] = {
103	DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
104	DEFINE_RES_IRQ(0),
105};
106
107/*
108 * Cells needs to be ordered so that the iDMA is created first. This is
109 * because we need to be sure the DMA is available when the host controller
110 * driver is probed.
111 */
112static const struct mfd_cell intel_lpss_idma64_cell = {
113	.name = LPSS_IDMA64_DRIVER_NAME,
114	.num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
115	.resources = intel_lpss_idma64_resources,
116};
117
118static const struct mfd_cell intel_lpss_i2c_cell = {
119	.name = "i2c_designware",
120	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
121	.resources = intel_lpss_dev_resources,
122};
123
124static const struct mfd_cell intel_lpss_uart_cell = {
125	.name = "dw-apb-uart",
126	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
127	.resources = intel_lpss_dev_resources,
128};
129
130static const struct mfd_cell intel_lpss_spi_cell = {
131	.name = "pxa2xx-spi",
132	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
133	.resources = intel_lpss_dev_resources,
134};
135
136static DEFINE_IDA(intel_lpss_devid_ida);
137static struct dentry *intel_lpss_debugfs;
138
139static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
140{
141	lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
142	lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
143}
144
145static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
146{
147	struct dentry *dir;
148
149	dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
150	if (IS_ERR(dir))
151		return PTR_ERR(dir);
152
153	/* Cache the values into lpss structure */
154	intel_lpss_cache_ltr(lpss);
155
156	debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
157	debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
158	debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
159
160	lpss->debugfs = dir;
161	return 0;
162}
163
164static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
165{
166	debugfs_remove_recursive(lpss->debugfs);
167}
168
169static void intel_lpss_ltr_set(struct device *dev, s32 val)
170{
171	struct intel_lpss *lpss = dev_get_drvdata(dev);
172	u32 ltr;
173
174	/*
175	 * Program latency tolerance (LTR) accordingly what has been asked
176	 * by the PM QoS layer or disable it in case we were passed
177	 * negative value or PM_QOS_LATENCY_ANY.
178	 */
179	ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
180
181	if (val == PM_QOS_LATENCY_ANY || val < 0) {
182		ltr &= ~LPSS_PRIV_LTR_REQ;
183	} else {
184		ltr |= LPSS_PRIV_LTR_REQ;
185		ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
186		ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
187
188		if (val > LPSS_PRIV_LTR_VALUE_MASK)
189			ltr |= LPSS_PRIV_LTR_SCALE_32US | val >> 5;
190		else
191			ltr |= LPSS_PRIV_LTR_SCALE_1US | val;
192	}
193
194	if (ltr == lpss->active_ltr)
195		return;
196
197	writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
198	writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
199
200	/* Cache the values into lpss structure */
201	intel_lpss_cache_ltr(lpss);
202}
203
204static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
205{
206	lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
207	dev_pm_qos_expose_latency_tolerance(lpss->dev);
208}
209
210static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
211{
212	dev_pm_qos_hide_latency_tolerance(lpss->dev);
213	lpss->dev->power.set_latency_tolerance = NULL;
214}
215
216static int intel_lpss_assign_devs(struct intel_lpss *lpss)
217{
218	const struct mfd_cell *cell;
219	unsigned int type;
220
221	type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
222	type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
223
224	switch (type) {
225	case LPSS_DEV_I2C:
226		cell = &intel_lpss_i2c_cell;
227		break;
228	case LPSS_DEV_UART:
229		cell = &intel_lpss_uart_cell;
230		break;
231	case LPSS_DEV_SPI:
232		cell = &intel_lpss_spi_cell;
233		break;
234	default:
235		return -ENODEV;
236	}
237
238	lpss->cell = devm_kmemdup(lpss->dev, cell, sizeof(*cell), GFP_KERNEL);
239	if (!lpss->cell)
240		return -ENOMEM;
241
242	lpss->type = type;
243
244	return 0;
245}
246
247static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
248{
249	return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
250}
251
252static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
253{
254	resource_size_t addr = lpss->info->mem->start;
255
256	lo_hi_writeq(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR);
257}
258
259static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
260{
261	u32 value = LPSS_PRIV_RESETS_FUNC | LPSS_PRIV_RESETS_IDMA;
262
263	/* Bring out the device from reset */
264	writel(value, lpss->priv + LPSS_PRIV_RESETS);
265}
266
267static void intel_lpss_init_dev(const struct intel_lpss *lpss)
268{
269	u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
270
271	/* Set the device in reset state */
272	writel(0, lpss->priv + LPSS_PRIV_RESETS);
273
274	intel_lpss_deassert_reset(lpss);
275
276	intel_lpss_set_remap_addr(lpss);
277
278	if (!intel_lpss_has_idma(lpss))
279		return;
280
281	/* Make sure that SPI multiblock DMA transfers are re-enabled */
282	if (lpss->type == LPSS_DEV_SPI)
283		writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
284}
285
286static void intel_lpss_unregister_clock_tree(struct clk *clk)
287{
288	struct clk *parent;
289
290	while (clk) {
291		parent = clk_get_parent(clk);
292		clk_unregister(clk);
293		clk = parent;
294	}
295}
296
297static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
298					     const char *devname,
299					     struct clk **clk)
300{
301	char name[32];
302	struct clk *tmp = *clk;
 
303
304	snprintf(name, sizeof(name), "%s-enable", devname);
305	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
306				lpss->priv, 0, 0, NULL);
307	if (IS_ERR(tmp))
308		return PTR_ERR(tmp);
309
310	snprintf(name, sizeof(name), "%s-div", devname);
311	tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
312					      0, lpss->priv, 1, 15, 16, 15,
313					      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
314					      NULL);
315	if (IS_ERR(tmp))
316		return PTR_ERR(tmp);
317	*clk = tmp;
318
 
 
 
 
 
 
319	snprintf(name, sizeof(name), "%s-update", devname);
320	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
321				CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
322	if (IS_ERR(tmp))
323		return PTR_ERR(tmp);
324	*clk = tmp;
325
326	return 0;
327}
328
329static int intel_lpss_register_clock(struct intel_lpss *lpss)
330{
331	const struct mfd_cell *cell = lpss->cell;
332	struct clk *clk;
333	char devname[24];
334	int ret;
335
336	if (!lpss->info->clk_rate)
337		return 0;
338
339	/* Root clock */
340	clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL, 0,
341				      lpss->info->clk_rate);
342	if (IS_ERR(clk))
343		return PTR_ERR(clk);
344
345	snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
346
347	/*
348	 * Support for clock divider only if it has some preset value.
349	 * Otherwise we assume that the divider is not used.
350	 */
351	if (lpss->type != LPSS_DEV_I2C) {
352		ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
353		if (ret)
354			goto err_clk_register;
355	}
356
357	ret = -ENOMEM;
358
359	/* Clock for the host controller */
360	lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
361	if (!lpss->clock)
362		goto err_clk_register;
363
364	lpss->clk = clk;
365
366	return 0;
367
368err_clk_register:
369	intel_lpss_unregister_clock_tree(clk);
370
371	return ret;
372}
373
374static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
375{
376	if (IS_ERR_OR_NULL(lpss->clk))
377		return;
378
379	clkdev_drop(lpss->clock);
380	intel_lpss_unregister_clock_tree(lpss->clk);
381}
382
383int intel_lpss_probe(struct device *dev,
384		     const struct intel_lpss_platform_info *info)
385{
386	struct intel_lpss *lpss;
387	int ret;
388
389	if (!info || !info->mem)
390		return -EINVAL;
391
392	if (info->irq < 0)
393		return info->irq;
394
395	lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
396	if (!lpss)
397		return -ENOMEM;
398
399	lpss->priv = devm_ioremap_uc(dev, info->mem->start + LPSS_PRIV_OFFSET,
400				  LPSS_PRIV_SIZE);
401	if (!lpss->priv)
402		return -ENOMEM;
403
404	lpss->info = info;
405	lpss->dev = dev;
406	lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
407
408	dev_set_drvdata(dev, lpss);
409
410	ret = intel_lpss_assign_devs(lpss);
411	if (ret)
412		return ret;
413
414	lpss->cell->swnode = info->swnode;
415	lpss->cell->ignore_resource_conflicts = info->ignore_resource_conflicts;
416
417	intel_lpss_init_dev(lpss);
418
419	lpss->devid = ida_alloc(&intel_lpss_devid_ida, GFP_KERNEL);
420	if (lpss->devid < 0)
421		return lpss->devid;
422
423	ret = intel_lpss_register_clock(lpss);
424	if (ret)
425		goto err_clk_register;
426
427	intel_lpss_ltr_expose(lpss);
428
429	ret = intel_lpss_debugfs_add(lpss);
430	if (ret)
431		dev_warn(dev, "Failed to create debugfs entries\n");
432
433	if (intel_lpss_has_idma(lpss)) {
434		ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
435				      1, info->mem, info->irq, NULL);
436		if (ret)
437			dev_warn(dev, "Failed to add %s, fallback to PIO\n",
438				 LPSS_IDMA64_DRIVER_NAME);
439	}
440
441	ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
442			      1, info->mem, info->irq, NULL);
443	if (ret)
444		goto err_remove_ltr;
445
446	dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
447
448	return 0;
449
450err_remove_ltr:
451	intel_lpss_debugfs_remove(lpss);
452	intel_lpss_ltr_hide(lpss);
453	intel_lpss_unregister_clock(lpss);
454
455err_clk_register:
456	ida_free(&intel_lpss_devid_ida, lpss->devid);
457
458	return ret;
459}
460EXPORT_SYMBOL_NS_GPL(intel_lpss_probe, INTEL_LPSS);
461
462void intel_lpss_remove(struct device *dev)
463{
464	struct intel_lpss *lpss = dev_get_drvdata(dev);
465
466	mfd_remove_devices(dev);
467	intel_lpss_debugfs_remove(lpss);
468	intel_lpss_ltr_hide(lpss);
469	intel_lpss_unregister_clock(lpss);
470	ida_free(&intel_lpss_devid_ida, lpss->devid);
471}
472EXPORT_SYMBOL_NS_GPL(intel_lpss_remove, INTEL_LPSS);
473
474static int resume_lpss_device(struct device *dev, void *data)
475{
476	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND))
477		pm_runtime_resume(dev);
478
479	return 0;
480}
481
482static int intel_lpss_prepare(struct device *dev)
483{
484	/*
485	 * Resume both child devices before entering system sleep. This
486	 * ensures that they are in proper state before they get suspended.
487	 */
488	device_for_each_child_reverse(dev, NULL, resume_lpss_device);
489	return 0;
490}
491
492static int intel_lpss_suspend(struct device *dev)
493{
494	struct intel_lpss *lpss = dev_get_drvdata(dev);
495	unsigned int i;
496
497	/* Save device context */
498	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
499		lpss->priv_ctx[i] = readl(lpss->priv + i * 4);
500
501	/*
502	 * If the device type is not UART, then put the controller into
503	 * reset. UART cannot be put into reset since S3/S0ix fail when
504	 * no_console_suspend flag is enabled.
505	 */
506	if (lpss->type != LPSS_DEV_UART)
507		writel(0, lpss->priv + LPSS_PRIV_RESETS);
508
509	return 0;
510}
511
512static int intel_lpss_resume(struct device *dev)
513{
514	struct intel_lpss *lpss = dev_get_drvdata(dev);
515	unsigned int i;
516
517	intel_lpss_deassert_reset(lpss);
518
519	/* Restore device context */
520	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
521		writel(lpss->priv_ctx[i], lpss->priv + i * 4);
522
523	return 0;
524}
525
526EXPORT_NS_GPL_DEV_PM_OPS(intel_lpss_pm_ops, INTEL_LPSS) = {
527	.prepare = pm_sleep_ptr(&intel_lpss_prepare),
528	LATE_SYSTEM_SLEEP_PM_OPS(intel_lpss_suspend, intel_lpss_resume)
529	RUNTIME_PM_OPS(intel_lpss_suspend, intel_lpss_resume, NULL)
530};
531
532static int __init intel_lpss_init(void)
533{
534	intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
535	return 0;
536}
537module_init(intel_lpss_init);
538
539static void __exit intel_lpss_exit(void)
540{
541	ida_destroy(&intel_lpss_devid_ida);
542	debugfs_remove(intel_lpss_debugfs);
543}
544module_exit(intel_lpss_exit);
545
546MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
547MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
548MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
549MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
550MODULE_DESCRIPTION("Intel LPSS core driver");
551MODULE_LICENSE("GPL v2");
552/*
553 * Ensure the DMA driver is loaded before the host controller device appears,
554 * so that the host controller driver can request its DMA channels as early
555 * as possible.
556 *
557 * If the DMA module is not there that's OK as well.
558 */
559MODULE_SOFTDEP("pre: platform:" LPSS_IDMA64_DRIVER_NAME);