[mirror_ubuntu-bionic-kernel.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/property.h>
#include <linux/seq_file.h>
#include <linux/io-64-nonatomic-lo-hi.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_PRIV_REG_COUNT	(LPSS_PRIV_SIZE / 4)
#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		0x40

#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;
	struct mfd_cell *cell;
	struct device *dev;
	void __iomem *priv;
	u32 priv_ctx[LPSS_PRIV_REG_COUNT];
	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)
{
	const struct mfd_cell *cell;
	unsigned int type;

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

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

	lpss->cell = devm_kmemdup(lpss->dev, cell, sizeof(*cell), GFP_KERNEL);
	if (!lpss->cell)
		return -ENOMEM;

	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;

	lo_hi_writeq(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR);
}

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);

	intel_lpss_set_remap_addr(lpss);

	if (!intel_lpss_has_idma(lpss))
		return;

	/* 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, 0,
				      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;

	lpss->cell->properties = info->properties;

	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);
	intel_lpss_unregister_clock(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)
{
	struct intel_lpss *lpss = dev_get_drvdata(dev);
	unsigned int i;

	/* Save device context */
	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
		lpss->priv_ctx[i] = readl(lpss->priv + i * 4);

	/*
	 * If the device type is not UART, then put the controller into
	 * reset. UART cannot be put into reset since S3/S0ix fail when
	 * no_console_suspend flag is enabled.
	 */
	if (lpss->type != LPSS_DEV_UART)
		writel(0, lpss->priv + LPSS_PRIV_RESETS);

	return 0;
}
EXPORT_SYMBOL_GPL(intel_lpss_suspend);

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

	intel_lpss_deassert_reset(lpss);

	/* Restore device context */
	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
		writel(lpss->priv_ctx[i], lpss->priv + i * 4);

	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>
e15ad215	27	#include <linux/property.h>
4b45efe8	28	#include <linux/seq_file.h>
9cf5c095	29	#include <linux/io-64-nonatomic-lo-hi.h>
689d4453	30
4b45efe8 AS	31	#include "intel-lpss.h"
	32
	33	#define LPSS_DEV_OFFSET 0x000
	34	#define LPSS_DEV_SIZE 0x200
	35	#define LPSS_PRIV_OFFSET 0x200
	36	#define LPSS_PRIV_SIZE 0x100
41a3da2b	37	#define LPSS_PRIV_REG_COUNT (LPSS_PRIV_SIZE / 4)
4b45efe8 AS	38	#define LPSS_IDMA64_OFFSET 0x800
	39	#define LPSS_IDMA64_SIZE 0x800
	40
	41	/* Offsets from lpss->priv */
	42	#define LPSS_PRIV_RESETS 0x04
	43	#define LPSS_PRIV_RESETS_FUNC BIT(2)
	44	#define LPSS_PRIV_RESETS_IDMA 0x3
	45
	46	#define LPSS_PRIV_ACTIVELTR 0x10
	47	#define LPSS_PRIV_IDLELTR 0x14
	48
	49	#define LPSS_PRIV_LTR_REQ BIT(15)
	50	#define LPSS_PRIV_LTR_SCALE_MASK 0xc00
	51	#define LPSS_PRIV_LTR_SCALE_1US 0x800
	52	#define LPSS_PRIV_LTR_SCALE_32US 0xc00
	53	#define LPSS_PRIV_LTR_VALUE_MASK 0x3ff
	54
	55	#define LPSS_PRIV_SSP_REG 0x20
	56	#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN BIT(0)
	57
689d4453	58	#define LPSS_PRIV_REMAP_ADDR 0x40
4b45efe8 AS	59
	60	#define LPSS_PRIV_CAPS 0xfc
	61	#define LPSS_PRIV_CAPS_NO_IDMA BIT(8)
	62	#define LPSS_PRIV_CAPS_TYPE_SHIFT 4
	63	#define LPSS_PRIV_CAPS_TYPE_MASK (0xf << LPSS_PRIV_CAPS_TYPE_SHIFT)
	64
	65	/* This matches the type field in CAPS register */
	66	enum intel_lpss_dev_type {
	67	LPSS_DEV_I2C = 0,
	68	LPSS_DEV_UART,
	69	LPSS_DEV_SPI,
	70	};
	71
	72	struct intel_lpss {
	73	const struct intel_lpss_platform_info *info;
	74	enum intel_lpss_dev_type type;
	75	struct clk *clk;
	76	struct clk_lookup *clock;
e15ad215	77	struct mfd_cell *cell;
4b45efe8 AS	78	struct device *dev;
4b45efe8 AS	79	void __iomem *priv;
41a3da2b	80	u32 priv_ctx[LPSS_PRIV_REG_COUNT];
4b45efe8 AS	81	int devid;
	82	u32 caps;
	83	u32 active_ltr;
	84	u32 idle_ltr;
	85	struct dentry *debugfs;
	86	};
	87
	88	static const struct resource intel_lpss_dev_resources[] = {
	89	DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
	90	DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
	91	DEFINE_RES_IRQ(0),
	92	};
	93
	94	static const struct resource intel_lpss_idma64_resources[] = {
	95	DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
	96	DEFINE_RES_IRQ(0),
	97	};
	98
	99	#define LPSS_IDMA64_DRIVER_NAME "idma64"
	100
	101	/*
	102	* Cells needs to be ordered so that the iDMA is created first. This is
	103	* because we need to be sure the DMA is available when the host controller
	104	* driver is probed.
	105	*/
	106	static const struct mfd_cell intel_lpss_idma64_cell = {
	107	.name = LPSS_IDMA64_DRIVER_NAME,
	108	.num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
	109	.resources = intel_lpss_idma64_resources,
	110	};
	111
	112	static const struct mfd_cell intel_lpss_i2c_cell = {
	113	.name = "i2c_designware",
	114	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
	115	.resources = intel_lpss_dev_resources,
	116	};
	117
	118	static const struct mfd_cell intel_lpss_uart_cell = {
	119	.name = "dw-apb-uart",
	120	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
	121	.resources = intel_lpss_dev_resources,
	122	};
	123
	124	static const struct mfd_cell intel_lpss_spi_cell = {
	125	.name = "pxa2xx-spi",
	126	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
	127	.resources = intel_lpss_dev_resources,
	128	};
	129
	130	static DEFINE_IDA(intel_lpss_devid_ida);
	131	static struct dentry *intel_lpss_debugfs;
	132
	133	static int intel_lpss_request_dma_module(const char *name)
	134	{
	135	static bool intel_lpss_dma_requested;
	136
	137	if (intel_lpss_dma_requested)
	138	return 0;
	139
	140	intel_lpss_dma_requested = true;
	141	return request_module("%s", name);
	142	}
	143
	144	static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
145	{
146	lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
147	lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
148	}
149
150	static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
151	{
152	struct dentry *dir;
153
154	dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
155	if (IS_ERR(dir))
156	return PTR_ERR(dir);
157
158	/* Cache the values into lpss structure */
159	intel_lpss_cache_ltr(lpss);
160
161	debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
162	debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
163	debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
164
165	lpss->debugfs = dir;
166	return 0;
167	}
168
169	static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
170	{
171	debugfs_remove_recursive(lpss->debugfs);
172	}
173
174	static void intel_lpss_ltr_set(struct device *dev, s32 val)
175	{
176	struct intel_lpss *lpss = dev_get_drvdata(dev);
177	u32 ltr;
178
179	/*
180	* Program latency tolerance (LTR) accordingly what has been asked
181	* by the PM QoS layer or disable it in case we were passed
182	* negative value or PM_QOS_LATENCY_ANY.
183	*/
184	ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
185
186	if (val == PM_QOS_LATENCY_ANY \|\| val < 0) {
187	ltr &= ~LPSS_PRIV_LTR_REQ;
188	} else {
189	ltr \|= LPSS_PRIV_LTR_REQ;
190	ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
191	ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
192
193	if (val > LPSS_PRIV_LTR_VALUE_MASK)
194	ltr \|= LPSS_PRIV_LTR_SCALE_32US \| val >> 5;
195	else
196	ltr \|= LPSS_PRIV_LTR_SCALE_1US \| val;
197	}
198
199	if (ltr == lpss->active_ltr)
200	return;
201
202	writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
203	writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
204
205	/* Cache the values into lpss structure */
206	intel_lpss_cache_ltr(lpss);
207	}
208
209	static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
210	{
211	lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
212	dev_pm_qos_expose_latency_tolerance(lpss->dev);
213	}
214
215	static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
216	{
217	dev_pm_qos_hide_latency_tolerance(lpss->dev);
218	lpss->dev->power.set_latency_tolerance = NULL;
219	}
220
221	static int intel_lpss_assign_devs(struct intel_lpss *lpss)
222	{
e15ad215	223	const struct mfd_cell *cell;
4b45efe8 AS	224	unsigned int type;
	225
	226	type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
	227	type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
	228
	229	switch (type) {
	230	case LPSS_DEV_I2C:
e15ad215	231	cell = &intel_lpss_i2c_cell;
4b45efe8 AS	232	break;
4b45efe8 AS	233	case LPSS_DEV_UART:
e15ad215	234	cell = &intel_lpss_uart_cell;
4b45efe8 AS	235	break;
4b45efe8 AS	236	case LPSS_DEV_SPI:
e15ad215	237	cell = &intel_lpss_spi_cell;
4b45efe8 AS	238	break;
	239	default:
	240	return -ENODEV;
	241	}
	242
e15ad215 MW	243	lpss->cell = devm_kmemdup(lpss->dev, cell, sizeof(*cell), GFP_KERNEL);
	244	if (!lpss->cell)
	245	return -ENOMEM;
	246
4b45efe8 AS	247	lpss->type = type;
	248
	249	return 0;
	250	}
	251
	252	static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
	253	{
	254	return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
	255	}
	256
	257	static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
	258	{
	259	resource_size_t addr = lpss->info->mem->start;
	260
689d4453	261	lo_hi_writeq(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR);
4b45efe8 AS	262	}
	263
	264	static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
	265	{
	266	u32 value = LPSS_PRIV_RESETS_FUNC \| LPSS_PRIV_RESETS_IDMA;
	267
	268	/* Bring out the device from reset */
	269	writel(value, lpss->priv + LPSS_PRIV_RESETS);
	270	}
	271
	272	static void intel_lpss_init_dev(const struct intel_lpss *lpss)
	273	{
	274	u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
	275
	276	intel_lpss_deassert_reset(lpss);
	277
83386ac4 AS	278	intel_lpss_set_remap_addr(lpss);
83386ac4 AS	279
4b45efe8 AS	280	if (!intel_lpss_has_idma(lpss))
	281	return;
	282
4b45efe8 AS	283	/* Make sure that SPI multiblock DMA transfers are re-enabled */
	284	if (lpss->type == LPSS_DEV_SPI)
	285	writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
	286	}
	287
	288	static void intel_lpss_unregister_clock_tree(struct clk *clk)
	289	{
	290	struct clk *parent;
	291
	292	while (clk) {
	293	parent = clk_get_parent(clk);
	294	clk_unregister(clk);
	295	clk = parent;
	296	}
	297	}
	298
	299	static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
	300	const char *devname,
	301	struct clk **clk)
	302	{
	303	char name[32];
	304	struct clk tmp = clk;
	305
	306	snprintf(name, sizeof(name), "%s-enable", devname);
	307	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
	308	lpss->priv, 0, 0, NULL);
	309	if (IS_ERR(tmp))
	310	return PTR_ERR(tmp);
	311
	312	snprintf(name, sizeof(name), "%s-div", devname);
	313	tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
	314	0, lpss->priv, 1, 15, 16, 15, 0,
	315	NULL);
	316	if (IS_ERR(tmp))
	317	return PTR_ERR(tmp);
	318	*clk = tmp;
	319
	320	snprintf(name, sizeof(name), "%s-update", devname);
	321	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
	322	CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
	323	if (IS_ERR(tmp))
	324	return PTR_ERR(tmp);
	325	*clk = tmp;
	326
	327	return 0;
	328	}
	329
	330	static int intel_lpss_register_clock(struct intel_lpss *lpss)
	331	{
	332	const struct mfd_cell *cell = lpss->cell;
	333	struct clk *clk;
	334	char devname[24];
	335	int ret;
	336
	337	if (!lpss->info->clk_rate)
	338	return 0;
	339
	340	/* Root clock */
0f7e70e7 SB	341	clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL, 0,
0f7e70e7 SB	342	lpss->info->clk_rate);
4b45efe8 AS	343	if (IS_ERR(clk))
	344	return PTR_ERR(clk);
	345
	346	snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
	347
	348	/*
	349	* Support for clock divider only if it has some preset value.
	350	* Otherwise we assume that the divider is not used.
	351	*/
	352	if (lpss->type != LPSS_DEV_I2C) {
	353	ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
	354	if (ret)
	355	goto err_clk_register;
	356	}
	357
	358	ret = -ENOMEM;
	359
	360	/* Clock for the host controller */
	361	lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
	362	if (!lpss->clock)
	363	goto err_clk_register;
	364
	365	lpss->clk = clk;
	366
	367	return 0;
	368
	369	err_clk_register:
	370	intel_lpss_unregister_clock_tree(clk);
	371
	372	return ret;
	373	}
	374
	375	static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
	376	{
	377	if (IS_ERR_OR_NULL(lpss->clk))
	378	return;
	379
	380	clkdev_drop(lpss->clock);
	381	intel_lpss_unregister_clock_tree(lpss->clk);
	382	}
	383
	384	int intel_lpss_probe(struct device *dev,
	385	const struct intel_lpss_platform_info *info)
	386	{
	387	struct intel_lpss *lpss;
	388	int ret;
	389
	390	if (!info \|\| !info->mem \|\| info->irq <= 0)
	391	return -EINVAL;
	392
	393	lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
	394	if (!lpss)
	395	return -ENOMEM;
	396
	397	lpss->priv = devm_ioremap(dev, info->mem->start + LPSS_PRIV_OFFSET,
	398	LPSS_PRIV_SIZE);
	399	if (!lpss->priv)
	400	return -ENOMEM;
	401
	402	lpss->info = info;
	403	lpss->dev = dev;
	404	lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
	405
	406	dev_set_drvdata(dev, lpss);
407
408	ret = intel_lpss_assign_devs(lpss);
409	if (ret)
410	return ret;
411
f4d05266	412	lpss->cell->properties = info->properties;
e15ad215	413
4b45efe8 AS	414	intel_lpss_init_dev(lpss);
	415
	416	lpss->devid = ida_simple_get(&intel_lpss_devid_ida, 0, 0, GFP_KERNEL);
	417	if (lpss->devid < 0)
	418	return lpss->devid;
	419
	420	ret = intel_lpss_register_clock(lpss);
	421	if (ret)
	422	goto err_clk_register;
	423
	424	intel_lpss_ltr_expose(lpss);
	425
	426	ret = intel_lpss_debugfs_add(lpss);
	427	if (ret)
	428	dev_warn(dev, "Failed to create debugfs entries\n");
	429
	430	if (intel_lpss_has_idma(lpss)) {
	431	/*
	432	* Ensure the DMA driver is loaded before the host
	433	* controller device appears, so that the host controller
	434	* driver can request its DMA channels as early as
	435	* possible.
	436	*
	437	* If the DMA module is not there that's OK as well.
	438	*/
	439	intel_lpss_request_dma_module(LPSS_IDMA64_DRIVER_NAME);
	440
	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	return 0;
	454
	455	err_remove_ltr:
	456	intel_lpss_debugfs_remove(lpss);
	457	intel_lpss_ltr_hide(lpss);
84cb36ca	458	intel_lpss_unregister_clock(lpss);
4b45efe8 AS	459
	460	err_clk_register:
	461	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
	462
	463	return ret;
	464	}
	465	EXPORT_SYMBOL_GPL(intel_lpss_probe);
	466
	467	void intel_lpss_remove(struct device *dev)
	468	{
	469	struct intel_lpss *lpss = dev_get_drvdata(dev);
	470
	471	mfd_remove_devices(dev);
	472	intel_lpss_debugfs_remove(lpss);
	473	intel_lpss_ltr_hide(lpss);
	474	intel_lpss_unregister_clock(lpss);
	475	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
	476	}
	477	EXPORT_SYMBOL_GPL(intel_lpss_remove);
	478
	479	static int resume_lpss_device(struct device dev, void data)
	480	{
	481	pm_runtime_resume(dev);
	482	return 0;
	483	}
	484
	485	int intel_lpss_prepare(struct device *dev)
	486	{
	487	/*
	488	* Resume both child devices before entering system sleep. This
	489	* ensures that they are in proper state before they get suspended.
	490	*/
	491	device_for_each_child_reverse(dev, NULL, resume_lpss_device);
	492	return 0;
	493	}
	494	EXPORT_SYMBOL_GPL(intel_lpss_prepare);
	495
	496	int intel_lpss_suspend(struct device *dev)
	497	{
41a3da2b HK	498	struct intel_lpss *lpss = dev_get_drvdata(dev);
	499	unsigned int i;
	500
	501	/* Save device context */
	502	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
	503	lpss->priv_ctx[i] = readl(lpss->priv + i * 4);
	504
0b471aaa FS	505	/*
	506	* If the device type is not UART, then put the controller into
	507	* reset. UART cannot be put into reset since S3/S0ix fail when
	508	* no_console_suspend flag is enabled.
	509	*/
	510	if (lpss->type != LPSS_DEV_UART)
	511	writel(0, lpss->priv + LPSS_PRIV_RESETS);
	512
4b45efe8 AS	513	return 0;
	514	}
	515	EXPORT_SYMBOL_GPL(intel_lpss_suspend);
	516
	517	int intel_lpss_resume(struct device *dev)
	518	{
	519	struct intel_lpss *lpss = dev_get_drvdata(dev);
41a3da2b	520	unsigned int i;
4b45efe8	521
41a3da2b HK	522	intel_lpss_deassert_reset(lpss);
	523
	524	/* Restore device context */
	525	for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
	526	writel(lpss->priv_ctx[i], lpss->priv + i * 4);
4b45efe8 AS	527
	528	return 0;
	529	}
	530	EXPORT_SYMBOL_GPL(intel_lpss_resume);
	531
	532	static int __init intel_lpss_init(void)
	533	{
	534	intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
	535	return 0;
	536	}
	537	module_init(intel_lpss_init);
	538
	539	static void __exit intel_lpss_exit(void)
	540	{
	541	debugfs_remove(intel_lpss_debugfs);
	542	}
	543	module_exit(intel_lpss_exit);
	544
	545	MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
	546	MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
	547	MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
	548	MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
	549	MODULE_DESCRIPTION("Intel LPSS core driver");
	550	MODULE_LICENSE("GPL v2");