[deliverable/linux.git] / drivers / mfd / intel-lpss.c

/*
 * Intel Sunrisepoint LPSS core support.
 *
 * Copyright (C) 2015, Intel Corporation
 *
 * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
 *          Mika Westerberg <mika.westerberg@linux.intel.com>
 *          Heikki Krogerus <heikki.krogerus@linux.intel.com>
 *          Jarkko Nikula <jarkko.nikula@linux.intel.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/debugfs.h>
#include <linux/idr.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/pm_qos.h>
#include <linux/pm_runtime.h>
#include <linux/seq_file.h>

#include "intel-lpss.h"

#define LPSS_DEV_OFFSET		0x000
#define LPSS_DEV_SIZE		0x200
#define LPSS_PRIV_OFFSET	0x200
#define LPSS_PRIV_SIZE		0x100
#define LPSS_IDMA64_OFFSET	0x800
#define LPSS_IDMA64_SIZE	0x800

/* Offsets from lpss->priv */
#define LPSS_PRIV_RESETS		0x04
#define LPSS_PRIV_RESETS_FUNC		BIT(2)
#define LPSS_PRIV_RESETS_IDMA		0x3

#define LPSS_PRIV_ACTIVELTR		0x10
#define LPSS_PRIV_IDLELTR		0x14

#define LPSS_PRIV_LTR_REQ		BIT(15)
#define LPSS_PRIV_LTR_SCALE_MASK	0xc00
#define LPSS_PRIV_LTR_SCALE_1US		0x800
#define LPSS_PRIV_LTR_SCALE_32US	0xc00
#define LPSS_PRIV_LTR_VALUE_MASK	0x3ff

#define LPSS_PRIV_SSP_REG		0x20
#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN	BIT(0)

#define LPSS_PRIV_REMAP_ADDR_LO		0x40
#define LPSS_PRIV_REMAP_ADDR_HI		0x44

#define LPSS_PRIV_CAPS			0xfc
#define LPSS_PRIV_CAPS_NO_IDMA		BIT(8)
#define LPSS_PRIV_CAPS_TYPE_SHIFT	4
#define LPSS_PRIV_CAPS_TYPE_MASK	(0xf << LPSS_PRIV_CAPS_TYPE_SHIFT)

/* This matches the type field in CAPS register */
enum intel_lpss_dev_type {
	LPSS_DEV_I2C = 0,
	LPSS_DEV_UART,
	LPSS_DEV_SPI,
};

struct intel_lpss {
	const struct intel_lpss_platform_info *info;
	enum intel_lpss_dev_type type;
	struct clk *clk;
	struct clk_lookup *clock;
	const struct mfd_cell *cell;
	struct device *dev;
	void __iomem *priv;
	int devid;
	u32 caps;
	u32 active_ltr;
	u32 idle_ltr;
	struct dentry *debugfs;
};

static const struct resource intel_lpss_dev_resources[] = {
	DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
	DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
	DEFINE_RES_IRQ(0),
};

static const struct resource intel_lpss_idma64_resources[] = {
	DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
	DEFINE_RES_IRQ(0),
};

#define LPSS_IDMA64_DRIVER_NAME		"idma64"

/*
 * Cells needs to be ordered so that the iDMA is created first. This is
 * because we need to be sure the DMA is available when the host controller
 * driver is probed.
 */
static const struct mfd_cell intel_lpss_idma64_cell = {
	.name = LPSS_IDMA64_DRIVER_NAME,
	.num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
	.resources = intel_lpss_idma64_resources,
};

static const struct mfd_cell intel_lpss_i2c_cell = {
	.name = "i2c_designware",
	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
	.resources = intel_lpss_dev_resources,
};

static const struct mfd_cell intel_lpss_uart_cell = {
	.name = "dw-apb-uart",
	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
	.resources = intel_lpss_dev_resources,
};

static const struct mfd_cell intel_lpss_spi_cell = {
	.name = "pxa2xx-spi",
	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
	.resources = intel_lpss_dev_resources,
};

static DEFINE_IDA(intel_lpss_devid_ida);
static struct dentry *intel_lpss_debugfs;

static int intel_lpss_request_dma_module(const char *name)
{
	static bool intel_lpss_dma_requested;

	if (intel_lpss_dma_requested)
		return 0;

	intel_lpss_dma_requested = true;
	return request_module("%s", name);
}

static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
{
	lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
	lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
}

static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
{
	struct dentry *dir;

	dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
	if (IS_ERR(dir))
		return PTR_ERR(dir);

	/* Cache the values into lpss structure */
	intel_lpss_cache_ltr(lpss);

	debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
	debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
	debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);

	lpss->debugfs = dir;
	return 0;
}

static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
{
	debugfs_remove_recursive(lpss->debugfs);
}

static void intel_lpss_ltr_set(struct device *dev, s32 val)
{
	struct intel_lpss *lpss = dev_get_drvdata(dev);
	u32 ltr;

	/*
	 * Program latency tolerance (LTR) accordingly what has been asked
	 * by the PM QoS layer or disable it in case we were passed
	 * negative value or PM_QOS_LATENCY_ANY.
	 */
	ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);

	if (val == PM_QOS_LATENCY_ANY || val < 0) {
		ltr &= ~LPSS_PRIV_LTR_REQ;
	} else {
		ltr |= LPSS_PRIV_LTR_REQ;
		ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
		ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;

		if (val > LPSS_PRIV_LTR_VALUE_MASK)
			ltr |= LPSS_PRIV_LTR_SCALE_32US | val >> 5;
		else
			ltr |= LPSS_PRIV_LTR_SCALE_1US | val;
	}

	if (ltr == lpss->active_ltr)
		return;

	writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
	writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);

	/* Cache the values into lpss structure */
	intel_lpss_cache_ltr(lpss);
}

static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
{
	lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
	dev_pm_qos_expose_latency_tolerance(lpss->dev);
}

static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
{
	dev_pm_qos_hide_latency_tolerance(lpss->dev);
	lpss->dev->power.set_latency_tolerance = NULL;
}

static int intel_lpss_assign_devs(struct intel_lpss *lpss)
{
	unsigned int type;

	type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
	type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;

	switch (type) {
	case LPSS_DEV_I2C:
		lpss->cell = &intel_lpss_i2c_cell;
		break;
	case LPSS_DEV_UART:
		lpss->cell = &intel_lpss_uart_cell;
		break;
	case LPSS_DEV_SPI:
		lpss->cell = &intel_lpss_spi_cell;
		break;
	default:
		return -ENODEV;
	}

	lpss->type = type;

	return 0;
}

static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
{
	return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
}

static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
{
	resource_size_t addr = lpss->info->mem->start;

	writel(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR_LO);
#if BITS_PER_LONG > 32
	writel(addr >> 32, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
#else
	writel(0, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
#endif
}

static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
{
	u32 value = LPSS_PRIV_RESETS_FUNC | LPSS_PRIV_RESETS_IDMA;

	/* Bring out the device from reset */
	writel(value, lpss->priv + LPSS_PRIV_RESETS);
}

static void intel_lpss_init_dev(const struct intel_lpss *lpss)
{
	u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;

	intel_lpss_deassert_reset(lpss);

	if (!intel_lpss_has_idma(lpss))
		return;

	intel_lpss_set_remap_addr(lpss);

	/* Make sure that SPI multiblock DMA transfers are re-enabled */
	if (lpss->type == LPSS_DEV_SPI)
		writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
}

static void intel_lpss_unregister_clock_tree(struct clk *clk)
{
	struct clk *parent;

	while (clk) {
		parent = clk_get_parent(clk);
		clk_unregister(clk);
		clk = parent;
	}
}

static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
					     const char *devname,
					     struct clk **clk)
{
	char name[32];
	struct clk *tmp = *clk;

	snprintf(name, sizeof(name), "%s-enable", devname);
	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
				lpss->priv, 0, 0, NULL);
	if (IS_ERR(tmp))
		return PTR_ERR(tmp);

	snprintf(name, sizeof(name), "%s-div", devname);
	tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
					      0, lpss->priv, 1, 15, 16, 15, 0,
					      NULL);
	if (IS_ERR(tmp))
		return PTR_ERR(tmp);
	*clk = tmp;

	snprintf(name, sizeof(name), "%s-update", devname);
	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
				CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
	if (IS_ERR(tmp))
		return PTR_ERR(tmp);
	*clk = tmp;

	return 0;
}

static int intel_lpss_register_clock(struct intel_lpss *lpss)
{
	const struct mfd_cell *cell = lpss->cell;
	struct clk *clk;
	char devname[24];
	int ret;

	if (!lpss->info->clk_rate)
		return 0;

	/* Root clock */
	clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL,
				      CLK_IS_ROOT, lpss->info->clk_rate);
	if (IS_ERR(clk))
		return PTR_ERR(clk);

	snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);

	/*
	 * Support for clock divider only if it has some preset value.
	 * Otherwise we assume that the divider is not used.
	 */
	if (lpss->type != LPSS_DEV_I2C) {
		ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
		if (ret)
			goto err_clk_register;
	}

	ret = -ENOMEM;

	/* Clock for the host controller */
	lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
	if (!lpss->clock)
		goto err_clk_register;

	lpss->clk = clk;

	return 0;

err_clk_register:
	intel_lpss_unregister_clock_tree(clk);

	return ret;
}

static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
{
	if (IS_ERR_OR_NULL(lpss->clk))
		return;

	clkdev_drop(lpss->clock);
	intel_lpss_unregister_clock_tree(lpss->clk);
}

int intel_lpss_probe(struct device *dev,
		     const struct intel_lpss_platform_info *info)
{
	struct intel_lpss *lpss;
	int ret;

	if (!info || !info->mem || info->irq <= 0)
		return -EINVAL;

	lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
	if (!lpss)
		return -ENOMEM;

	lpss->priv = devm_ioremap(dev, info->mem->start + LPSS_PRIV_OFFSET,
				  LPSS_PRIV_SIZE);
	if (!lpss->priv)
		return -ENOMEM;

	lpss->info = info;
	lpss->dev = dev;
	lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);

	dev_set_drvdata(dev, lpss);

	ret = intel_lpss_assign_devs(lpss);
	if (ret)
		return ret;

	intel_lpss_init_dev(lpss);

	lpss->devid = ida_simple_get(&intel_lpss_devid_ida, 0, 0, GFP_KERNEL);
	if (lpss->devid < 0)
		return lpss->devid;

	ret = intel_lpss_register_clock(lpss);
	if (ret)
		goto err_clk_register;

	intel_lpss_ltr_expose(lpss);

	ret = intel_lpss_debugfs_add(lpss);
	if (ret)
		dev_warn(dev, "Failed to create debugfs entries\n");

	if (intel_lpss_has_idma(lpss)) {
		/*
		 * Ensure the DMA driver is loaded before the host
		 * controller device appears, so that the host controller
		 * driver can request its DMA channels as early as
		 * possible.
		 *
		 * If the DMA module is not there that's OK as well.
		 */
		intel_lpss_request_dma_module(LPSS_IDMA64_DRIVER_NAME);

		ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
				      1, info->mem, info->irq, NULL);
		if (ret)
			dev_warn(dev, "Failed to add %s, fallback to PIO\n",
				 LPSS_IDMA64_DRIVER_NAME);
	}

	ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
			      1, info->mem, info->irq, NULL);
	if (ret)
		goto err_remove_ltr;

	return 0;

err_remove_ltr:
	intel_lpss_debugfs_remove(lpss);
	intel_lpss_ltr_hide(lpss);

err_clk_register:
	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);

	return ret;
}
EXPORT_SYMBOL_GPL(intel_lpss_probe);

void intel_lpss_remove(struct device *dev)
{
	struct intel_lpss *lpss = dev_get_drvdata(dev);

	mfd_remove_devices(dev);
	intel_lpss_debugfs_remove(lpss);
	intel_lpss_ltr_hide(lpss);
	intel_lpss_unregister_clock(lpss);
	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
}
EXPORT_SYMBOL_GPL(intel_lpss_remove);

static int resume_lpss_device(struct device *dev, void *data)
{
	pm_runtime_resume(dev);
	return 0;
}

int intel_lpss_prepare(struct device *dev)
{
	/*
	 * Resume both child devices before entering system sleep. This
	 * ensures that they are in proper state before they get suspended.
	 */
	device_for_each_child_reverse(dev, NULL, resume_lpss_device);
	return 0;
}
EXPORT_SYMBOL_GPL(intel_lpss_prepare);

int intel_lpss_suspend(struct device *dev)
{
	return 0;
}
EXPORT_SYMBOL_GPL(intel_lpss_suspend);

int intel_lpss_resume(struct device *dev)
{
	struct intel_lpss *lpss = dev_get_drvdata(dev);

	intel_lpss_init_dev(lpss);

	return 0;
}
EXPORT_SYMBOL_GPL(intel_lpss_resume);

static int __init intel_lpss_init(void)
{
	intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
	return 0;
}
module_init(intel_lpss_init);

static void __exit intel_lpss_exit(void)
{
	debugfs_remove(intel_lpss_debugfs);
}
module_exit(intel_lpss_exit);

MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
MODULE_DESCRIPTION("Intel LPSS core driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
4b45efe8 AS	1	/*
	2	* Intel Sunrisepoint LPSS core support.
	3	*
	4	* Copyright (C) 2015, Intel Corporation
	5	*
	6	* Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
	7	* Mika Westerberg <mika.westerberg@linux.intel.com>
	8	* Heikki Krogerus <heikki.krogerus@linux.intel.com>
	9	* Jarkko Nikula <jarkko.nikula@linux.intel.com>
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License version 2 as
	13	* published by the Free Software Foundation.
	14	*/
	15
	16	#include <linux/clk.h>
	17	#include <linux/clkdev.h>
	18	#include <linux/clk-provider.h>
	19	#include <linux/debugfs.h>
	20	#include <linux/idr.h>
	21	#include <linux/ioport.h>
	22	#include <linux/kernel.h>
	23	#include <linux/module.h>
	24	#include <linux/mfd/core.h>
	25	#include <linux/pm_qos.h>
	26	#include <linux/pm_runtime.h>
	27	#include <linux/seq_file.h>
	28
	29	#include "intel-lpss.h"
	30
	31	#define LPSS_DEV_OFFSET 0x000
	32	#define LPSS_DEV_SIZE 0x200
	33	#define LPSS_PRIV_OFFSET 0x200
	34	#define LPSS_PRIV_SIZE 0x100
	35	#define LPSS_IDMA64_OFFSET 0x800
	36	#define LPSS_IDMA64_SIZE 0x800
	37
	38	/* Offsets from lpss->priv */
	39	#define LPSS_PRIV_RESETS 0x04
	40	#define LPSS_PRIV_RESETS_FUNC BIT(2)
	41	#define LPSS_PRIV_RESETS_IDMA 0x3
	42
	43	#define LPSS_PRIV_ACTIVELTR 0x10
	44	#define LPSS_PRIV_IDLELTR 0x14
	45
	46	#define LPSS_PRIV_LTR_REQ BIT(15)
	47	#define LPSS_PRIV_LTR_SCALE_MASK 0xc00
	48	#define LPSS_PRIV_LTR_SCALE_1US 0x800
	49	#define LPSS_PRIV_LTR_SCALE_32US 0xc00
	50	#define LPSS_PRIV_LTR_VALUE_MASK 0x3ff
	51
	52	#define LPSS_PRIV_SSP_REG 0x20
	53	#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN BIT(0)
	54
	55	#define LPSS_PRIV_REMAP_ADDR_LO 0x40
	56	#define LPSS_PRIV_REMAP_ADDR_HI 0x44
	57
	58	#define LPSS_PRIV_CAPS 0xfc
	59	#define LPSS_PRIV_CAPS_NO_IDMA BIT(8)
	60	#define LPSS_PRIV_CAPS_TYPE_SHIFT 4
	61	#define LPSS_PRIV_CAPS_TYPE_MASK (0xf << LPSS_PRIV_CAPS_TYPE_SHIFT)
	62
	63	/* This matches the type field in CAPS register */
	64	enum intel_lpss_dev_type {
65	LPSS_DEV_I2C = 0,
66	LPSS_DEV_UART,
67	LPSS_DEV_SPI,
68	};
69
70	struct intel_lpss {
71	const struct intel_lpss_platform_info *info;
72	enum intel_lpss_dev_type type;
73	struct clk *clk;
74	struct clk_lookup *clock;
75	const struct mfd_cell *cell;
76	struct device *dev;
77	void __iomem *priv;
78	int devid;
79	u32 caps;
80	u32 active_ltr;
81	u32 idle_ltr;
82	struct dentry *debugfs;
83	};
84
85	static const struct resource intel_lpss_dev_resources[] = {
86	DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
87	DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
88	DEFINE_RES_IRQ(0),
89	};
90
91	static const struct resource intel_lpss_idma64_resources[] = {
92	DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
93	DEFINE_RES_IRQ(0),
94	};
95
96	#define LPSS_IDMA64_DRIVER_NAME "idma64"
97
98	/*
99	* Cells needs to be ordered so that the iDMA is created first. This is
100	* because we need to be sure the DMA is available when the host controller
101	* driver is probed.
102	*/
103	static const struct mfd_cell intel_lpss_idma64_cell = {
104	.name = LPSS_IDMA64_DRIVER_NAME,
105	.num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
106	.resources = intel_lpss_idma64_resources,
107	};
108
109	static const struct mfd_cell intel_lpss_i2c_cell = {
110	.name = "i2c_designware",
111	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
112	.resources = intel_lpss_dev_resources,
113	};
114
115	static const struct mfd_cell intel_lpss_uart_cell = {
116	.name = "dw-apb-uart",
117	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
118	.resources = intel_lpss_dev_resources,
119	};
120
121	static const struct mfd_cell intel_lpss_spi_cell = {
122	.name = "pxa2xx-spi",
123	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
124	.resources = intel_lpss_dev_resources,
125	};
126
127	static DEFINE_IDA(intel_lpss_devid_ida);
128	static struct dentry *intel_lpss_debugfs;
129
130	static int intel_lpss_request_dma_module(const char *name)
131	{
132	static bool intel_lpss_dma_requested;
133
134	if (intel_lpss_dma_requested)
135	return 0;
136
137	intel_lpss_dma_requested = true;
138	return request_module("%s", name);
139	}
140
141	static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
142	{
143	lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
144	lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
145	}
146
147	static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
148	{
149	struct dentry *dir;
150
151	dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
152	if (IS_ERR(dir))
153	return PTR_ERR(dir);
154
155	/* Cache the values into lpss structure */
156	intel_lpss_cache_ltr(lpss);
157
158	debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
159	debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
160	debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
161
162	lpss->debugfs = dir;
163	return 0;
164	}
165
166	static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
167	{
168	debugfs_remove_recursive(lpss->debugfs);
169	}
170
171	static void intel_lpss_ltr_set(struct device *dev, s32 val)
172	{
173	struct intel_lpss *lpss = dev_get_drvdata(dev);
174	u32 ltr;
175
176	/*
177	* Program latency tolerance (LTR) accordingly what has been asked
178	* by the PM QoS layer or disable it in case we were passed
179	* negative value or PM_QOS_LATENCY_ANY.
180	*/
181	ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
182
183	if (val == PM_QOS_LATENCY_ANY \|\| val < 0) {
184	ltr &= ~LPSS_PRIV_LTR_REQ;
185	} else {
186	ltr \|= LPSS_PRIV_LTR_REQ;
187	ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
188	ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
189
190	if (val > LPSS_PRIV_LTR_VALUE_MASK)
191	ltr \|= LPSS_PRIV_LTR_SCALE_32US \| val >> 5;
192	else
193	ltr \|= LPSS_PRIV_LTR_SCALE_1US \| val;
194	}
195
196	if (ltr == lpss->active_ltr)
197	return;
198
199	writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
200	writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
201
202	/* Cache the values into lpss structure */
203	intel_lpss_cache_ltr(lpss);
204	}
205
206	static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
207	{
208	lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
209	dev_pm_qos_expose_latency_tolerance(lpss->dev);
210	}
211
212	static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
213	{
214	dev_pm_qos_hide_latency_tolerance(lpss->dev);
215	lpss->dev->power.set_latency_tolerance = NULL;
216	}
217
218	static int intel_lpss_assign_devs(struct intel_lpss *lpss)
219	{
220	unsigned int type;
221
222	type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
223	type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
224
225	switch (type) {
226	case LPSS_DEV_I2C:
227	lpss->cell = &intel_lpss_i2c_cell;
228	break;
229	case LPSS_DEV_UART:
230	lpss->cell = &intel_lpss_uart_cell;
231	break;
232	case LPSS_DEV_SPI:
233	lpss->cell = &intel_lpss_spi_cell;
234	break;
235	default:
236	return -ENODEV;
237	}
238
239	lpss->type = type;
240
241	return 0;
242	}
243
244	static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
245	{
246	return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
247	}
248
249	static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
250	{
251	resource_size_t addr = lpss->info->mem->start;
252
253	writel(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR_LO);
254	#if BITS_PER_LONG > 32
255	writel(addr >> 32, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
256	#else
257	writel(0, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
258	#endif
259	}
260
261	static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
262	{
263	u32 value = LPSS_PRIV_RESETS_FUNC \| LPSS_PRIV_RESETS_IDMA;
264
265	/* Bring out the device from reset */
266	writel(value, lpss->priv + LPSS_PRIV_RESETS);
267	}
268
269	static void intel_lpss_init_dev(const struct intel_lpss *lpss)
270	{
271	u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
272
273	intel_lpss_deassert_reset(lpss);
274
275	if (!intel_lpss_has_idma(lpss))
276	return;
277
278	intel_lpss_set_remap_addr(lpss);
279
280	/* Make sure that SPI multiblock DMA transfers are re-enabled */
281	if (lpss->type == LPSS_DEV_SPI)
282	writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
283	}
284
285	static void intel_lpss_unregister_clock_tree(struct clk *clk)
286	{
287	struct clk *parent;
288
289	while (clk) {
290	parent = clk_get_parent(clk);
291	clk_unregister(clk);
292	clk = parent;
293	}
294	}
295
296	static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
297	const char *devname,
298	struct clk **clk)
299	{
300	char name[32];
301	struct clk tmp = clk;
302
303	snprintf(name, sizeof(name), "%s-enable", devname);
304	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
305	lpss->priv, 0, 0, NULL);
306	if (IS_ERR(tmp))
307	return PTR_ERR(tmp);
308
309	snprintf(name, sizeof(name), "%s-div", devname);
310	tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
311	0, lpss->priv, 1, 15, 16, 15, 0,
312	NULL);
313	if (IS_ERR(tmp))
314	return PTR_ERR(tmp);
315	*clk = tmp;
316
317	snprintf(name, sizeof(name), "%s-update", devname);
318	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
319	CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
320	if (IS_ERR(tmp))
321	return PTR_ERR(tmp);
322	*clk = tmp;
323
324	return 0;
325	}
326
327	static int intel_lpss_register_clock(struct intel_lpss *lpss)
328	{
329	const struct mfd_cell *cell = lpss->cell;
330	struct clk *clk;
331	char devname[24];
332	int ret;
333
334	if (!lpss->info->clk_rate)
335	return 0;
336
337	/* Root clock */
338	clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL,
339	CLK_IS_ROOT, lpss->info->clk_rate);
340	if (IS_ERR(clk))
341	return PTR_ERR(clk);
342
343	snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
344
345	/*
346	* Support for clock divider only if it has some preset value.
347	* Otherwise we assume that the divider is not used.
348	*/
349	if (lpss->type != LPSS_DEV_I2C) {
350	ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
351	if (ret)
352	goto err_clk_register;
353	}
354
355	ret = -ENOMEM;
356
357	/* Clock for the host controller */
358	lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
359	if (!lpss->clock)
360	goto err_clk_register;
361
362	lpss->clk = clk;
363
364	return 0;
365
366	err_clk_register:
367	intel_lpss_unregister_clock_tree(clk);
368
369	return ret;
370	}
371
372	static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
373	{
374	if (IS_ERR_OR_NULL(lpss->clk))
375	return;
376
377	clkdev_drop(lpss->clock);
378	intel_lpss_unregister_clock_tree(lpss->clk);
379	}
380
381	int intel_lpss_probe(struct device *dev,
382	const struct intel_lpss_platform_info *info)
383	{
384	struct intel_lpss *lpss;
385	int ret;
386
387	if (!info \|\| !info->mem \|\| info->irq <= 0)
388	return -EINVAL;
389
390	lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
391	if (!lpss)
392	return -ENOMEM;
393
394	lpss->priv = devm_ioremap(dev, info->mem->start + LPSS_PRIV_OFFSET,
395	LPSS_PRIV_SIZE);
396	if (!lpss->priv)
397	return -ENOMEM;
398
399	lpss->info = info;
400	lpss->dev = dev;
401	lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
402
403	dev_set_drvdata(dev, lpss);
404
405	ret = intel_lpss_assign_devs(lpss);
406	if (ret)
407	return ret;
408
409	intel_lpss_init_dev(lpss);
410
411	lpss->devid = ida_simple_get(&intel_lpss_devid_ida, 0, 0, GFP_KERNEL);
412	if (lpss->devid < 0)
413	return lpss->devid;
414
415	ret = intel_lpss_register_clock(lpss);
416	if (ret)
417	goto err_clk_register;
418
419	intel_lpss_ltr_expose(lpss);
420
421	ret = intel_lpss_debugfs_add(lpss);
422	if (ret)
423	dev_warn(dev, "Failed to create debugfs entries\n");
424
425	if (intel_lpss_has_idma(lpss)) {
426	/*
427	* Ensure the DMA driver is loaded before the host
428	* controller device appears, so that the host controller
429	* driver can request its DMA channels as early as
430	* possible.
431	*
432	* If the DMA module is not there that's OK as well.
433	*/
434	intel_lpss_request_dma_module(LPSS_IDMA64_DRIVER_NAME);
435
436	ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
437	1, info->mem, info->irq, NULL);
438	if (ret)
439	dev_warn(dev, "Failed to add %s, fallback to PIO\n",
440	LPSS_IDMA64_DRIVER_NAME);
441	}
442
443	ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
444	1, info->mem, info->irq, NULL);
445	if (ret)
446	goto err_remove_ltr;
447
448	return 0;
449
450	err_remove_ltr:
451	intel_lpss_debugfs_remove(lpss);
452	intel_lpss_ltr_hide(lpss);
453
454	err_clk_register:
455	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
456
457	return ret;
458	}
459	EXPORT_SYMBOL_GPL(intel_lpss_probe);
460
461	void intel_lpss_remove(struct device *dev)
462	{
463	struct intel_lpss *lpss = dev_get_drvdata(dev);
464
465	mfd_remove_devices(dev);
466	intel_lpss_debugfs_remove(lpss);
467	intel_lpss_ltr_hide(lpss);
468	intel_lpss_unregister_clock(lpss);
469	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
470	}
471	EXPORT_SYMBOL_GPL(intel_lpss_remove);
472
473	static int resume_lpss_device(struct device dev, void data)
474	{
475	pm_runtime_resume(dev);
476	return 0;
477	}
478
479	int intel_lpss_prepare(struct device *dev)
480	{
481	/*
482	* Resume both child devices before entering system sleep. This
483	* ensures that they are in proper state before they get suspended.
484	*/
485	device_for_each_child_reverse(dev, NULL, resume_lpss_device);
486	return 0;
487	}
488	EXPORT_SYMBOL_GPL(intel_lpss_prepare);
489
490	int intel_lpss_suspend(struct device *dev)
491	{
492	return 0;
493	}
494	EXPORT_SYMBOL_GPL(intel_lpss_suspend);
495
496	int intel_lpss_resume(struct device *dev)
497	{
498	struct intel_lpss *lpss = dev_get_drvdata(dev);
499
500	intel_lpss_init_dev(lpss);
501
502	return 0;
503	}
504	EXPORT_SYMBOL_GPL(intel_lpss_resume);
505
506	static int __init intel_lpss_init(void)
507	{
508	intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
509	return 0;
510	}
511	module_init(intel_lpss_init);
512
513	static void __exit intel_lpss_exit(void)
514	{
515	debugfs_remove(intel_lpss_debugfs);
516	}
517	module_exit(intel_lpss_exit);
518
519	MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
520	MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
521	MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
522	MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
523	MODULE_DESCRIPTION("Intel LPSS core driver");
524	MODULE_LICENSE("GPL v2");