[thirdparty/linux.git] / drivers / i2c / busses / i2c-amd-mp2-pci.c

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * AMD MP2 PCIe communication driver
 *
 * Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
 *          Elie Morisse <syniurge@gmail.com>
 */

#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include "i2c-amd-mp2.h"

#include <linux/io-64-nonatomic-lo-hi.h>

static void amd_mp2_c2p_mutex_lock(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;

	/* there is only one data mailbox for two i2c adapters */
	mutex_lock(&privdata->c2p_lock);
	privdata->c2p_lock_busid = i2c_common->bus_id;
}

static void amd_mp2_c2p_mutex_unlock(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;

	if (unlikely(privdata->c2p_lock_busid != i2c_common->bus_id)) {
		dev_warn(ndev_dev(privdata),
			 "bus %d attempting to unlock C2P locked by bus %d\n",
			 i2c_common->bus_id, privdata->c2p_lock_busid);
		return;
	}

	mutex_unlock(&privdata->c2p_lock);
}

static int amd_mp2_cmd(struct amd_i2c_common *i2c_common,
		       union i2c_cmd_base i2c_cmd_base)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	void __iomem *reg;

	i2c_common->reqcmd = i2c_cmd_base.s.i2c_cmd;

	reg = privdata->mmio + ((i2c_cmd_base.s.bus_id == 1) ?
				AMD_C2P_MSG1 : AMD_C2P_MSG0);
	writel(i2c_cmd_base.ul, reg);

	return 0;
}

int amd_mp2_bus_enable_set(struct amd_i2c_common *i2c_common, bool enable)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	union i2c_cmd_base i2c_cmd_base;

	dev_dbg(ndev_dev(privdata), "%s id: %d\n", __func__,
		i2c_common->bus_id);

	i2c_cmd_base.ul = 0;
	i2c_cmd_base.s.i2c_cmd = enable ? i2c_enable : i2c_disable;
	i2c_cmd_base.s.bus_id = i2c_common->bus_id;
	i2c_cmd_base.s.i2c_speed = i2c_common->i2c_speed;

	amd_mp2_c2p_mutex_lock(i2c_common);

	return amd_mp2_cmd(i2c_common, i2c_cmd_base);
}
EXPORT_SYMBOL_GPL(amd_mp2_bus_enable_set);

static void amd_mp2_cmd_rw_fill(struct amd_i2c_common *i2c_common,
				union i2c_cmd_base *i2c_cmd_base,
				enum i2c_cmd reqcmd)
{
	i2c_cmd_base->s.i2c_cmd = reqcmd;
	i2c_cmd_base->s.bus_id = i2c_common->bus_id;
	i2c_cmd_base->s.i2c_speed = i2c_common->i2c_speed;
	i2c_cmd_base->s.slave_addr = i2c_common->msg->addr;
	i2c_cmd_base->s.length = i2c_common->msg->len;
}

int amd_mp2_rw(struct amd_i2c_common *i2c_common, enum i2c_cmd reqcmd)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	union i2c_cmd_base i2c_cmd_base;

	amd_mp2_cmd_rw_fill(i2c_common, &i2c_cmd_base, reqcmd);
	amd_mp2_c2p_mutex_lock(i2c_common);

	if (i2c_common->msg->len <= 32) {
		i2c_cmd_base.s.mem_type = use_c2pmsg;
		if (reqcmd == i2c_write)
			memcpy_toio(privdata->mmio + AMD_C2P_MSG2,
				    i2c_common->msg->buf,
				    i2c_common->msg->len);
	} else {
		i2c_cmd_base.s.mem_type = use_dram;
		writeq((u64)i2c_common->dma_addr,
		       privdata->mmio + AMD_C2P_MSG2);
	}

	return amd_mp2_cmd(i2c_common, i2c_cmd_base);
}
EXPORT_SYMBOL_GPL(amd_mp2_rw);

static void amd_mp2_pci_check_rw_event(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	int len = i2c_common->eventval.r.length;
	u32 slave_addr = i2c_common->eventval.r.slave_addr;
	bool err = false;

	if (unlikely(len != i2c_common->msg->len)) {
		dev_err(ndev_dev(privdata),
			"length %d in event doesn't match buffer length %d!\n",
			len, i2c_common->msg->len);
		err = true;
	}

	if (unlikely(slave_addr != i2c_common->msg->addr)) {
		dev_err(ndev_dev(privdata),
			"unexpected slave address %x (expected: %x)!\n",
			slave_addr, i2c_common->msg->addr);
		err = true;
	}

	if (!err)
		i2c_common->cmd_success = true;
}

static void __amd_mp2_process_event(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	enum status_type sts = i2c_common->eventval.r.status;
	enum response_type res = i2c_common->eventval.r.response;
	int len = i2c_common->eventval.r.length;

	if (res != command_success) {
		if (res != command_failed)
			dev_err(ndev_dev(privdata), "invalid response to i2c command!\n");
		return;
	}

	switch (i2c_common->reqcmd) {
	case i2c_read:
		if (sts == i2c_readcomplete_event) {
			amd_mp2_pci_check_rw_event(i2c_common);
			if (len <= 32)
				memcpy_fromio(i2c_common->msg->buf,
					      privdata->mmio + AMD_C2P_MSG2,
					      len);
		} else if (sts != i2c_readfail_event) {
			dev_err(ndev_dev(privdata),
				"invalid i2c status after read (%d)!\n", sts);
		}
		break;
	case i2c_write:
		if (sts == i2c_writecomplete_event)
			amd_mp2_pci_check_rw_event(i2c_common);
		else if (sts != i2c_writefail_event)
			dev_err(ndev_dev(privdata),
				"invalid i2c status after write (%d)!\n", sts);
		break;
	case i2c_enable:
		if (sts == i2c_busenable_complete)
			i2c_common->cmd_success = true;
		else if (sts != i2c_busenable_failed)
			dev_err(ndev_dev(privdata),
				"invalid i2c status after bus enable (%d)!\n",
				sts);
		break;
	case i2c_disable:
		if (sts == i2c_busdisable_complete)
			i2c_common->cmd_success = true;
		else if (sts != i2c_busdisable_failed)
			dev_err(ndev_dev(privdata),
				"invalid i2c status after bus disable (%d)!\n",
				sts);
		break;
	default:
		break;
	}
}

void amd_mp2_process_event(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;

	if (unlikely(i2c_common->reqcmd == i2c_none)) {
		dev_warn(ndev_dev(privdata),
			 "received msg but no cmd was sent (bus = %d)!\n",
			 i2c_common->bus_id);
		return;
	}

	__amd_mp2_process_event(i2c_common);

	i2c_common->reqcmd = i2c_none;
	amd_mp2_c2p_mutex_unlock(i2c_common);
}
EXPORT_SYMBOL_GPL(amd_mp2_process_event);

static irqreturn_t amd_mp2_irq_isr(int irq, void *dev)
{
	struct amd_mp2_dev *privdata = dev;
	struct amd_i2c_common *i2c_common;
	u32 val;
	unsigned int bus_id;
	void __iomem *reg;
	enum irqreturn ret = IRQ_NONE;

	for (bus_id = 0; bus_id < 2; bus_id++) {
		i2c_common = privdata->busses[bus_id];
		if (!i2c_common)
			continue;

		reg = privdata->mmio + ((bus_id == 0) ?
					AMD_P2C_MSG1 : AMD_P2C_MSG2);
		val = readl(reg);
		if (val != 0) {
			writel(0, reg);
			writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
			i2c_common->eventval.ul = val;
			i2c_common->cmd_completion(i2c_common);

			ret = IRQ_HANDLED;
		}
	}

	if (ret != IRQ_HANDLED) {
		val = readl(privdata->mmio + AMD_P2C_MSG_INTEN);
		if (val != 0) {
			writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
			dev_warn(ndev_dev(privdata),
				 "received irq without message\n");
			ret = IRQ_HANDLED;
		}
	}

	return ret;
}

void amd_mp2_rw_timeout(struct amd_i2c_common *i2c_common)
{
	i2c_common->reqcmd = i2c_none;
	amd_mp2_c2p_mutex_unlock(i2c_common);
}
EXPORT_SYMBOL_GPL(amd_mp2_rw_timeout);

int amd_mp2_register_cb(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;

	if (i2c_common->bus_id > 1)
		return -EINVAL;

	if (privdata->busses[i2c_common->bus_id]) {
		dev_err(ndev_dev(privdata),
			"Bus %d already taken!\n", i2c_common->bus_id);
		return -EINVAL;
	}

	privdata->busses[i2c_common->bus_id] = i2c_common;

	return 0;
}
EXPORT_SYMBOL_GPL(amd_mp2_register_cb);

int amd_mp2_unregister_cb(struct amd_i2c_common *i2c_common)
{
	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;

	privdata->busses[i2c_common->bus_id] = NULL;

	return 0;
}
EXPORT_SYMBOL_GPL(amd_mp2_unregister_cb);

static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata)
{
	int reg;

	for (reg = AMD_C2P_MSG0; reg <= AMD_C2P_MSG9; reg += 4)
		writel(0, privdata->mmio + reg);

	for (reg = AMD_P2C_MSG1; reg <= AMD_P2C_MSG2; reg += 4)
		writel(0, privdata->mmio + reg);
}

static int amd_mp2_pci_init(struct amd_mp2_dev *privdata,
			    struct pci_dev *pci_dev)
{
	int rc;

	pci_set_drvdata(pci_dev, privdata);

	rc = pcim_enable_device(pci_dev);
	if (rc) {
		dev_err(ndev_dev(privdata), "Failed to enable MP2 PCI device\n");
		goto err_pci_enable;
	}

	rc = pcim_iomap_regions(pci_dev, 1 << 2, pci_name(pci_dev));
	if (rc) {
		dev_err(ndev_dev(privdata), "I/O memory remapping failed\n");
		goto err_pci_enable;
	}
	privdata->mmio = pcim_iomap_table(pci_dev)[2];

	pci_set_master(pci_dev);

	rc = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(64));
	if (rc) {
		rc = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(32));
		if (rc)
			goto err_dma_mask;
	}

	/* Set up intx irq */
	writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
	pci_intx(pci_dev, 1);
	rc = devm_request_irq(&pci_dev->dev, pci_dev->irq, amd_mp2_irq_isr,
			      IRQF_SHARED, dev_name(&pci_dev->dev), privdata);
	if (rc)
		dev_err(&pci_dev->dev, "Failure requesting irq %i: %d\n",
			pci_dev->irq, rc);

	return rc;

err_dma_mask:
	pci_clear_master(pci_dev);
err_pci_enable:
	pci_set_drvdata(pci_dev, NULL);
	return rc;
}

static int amd_mp2_pci_probe(struct pci_dev *pci_dev,
			     const struct pci_device_id *id)
{
	struct amd_mp2_dev *privdata;
	int rc;

	privdata = devm_kzalloc(&pci_dev->dev, sizeof(*privdata), GFP_KERNEL);
	if (!privdata)
		return -ENOMEM;

	privdata->pci_dev = pci_dev;
	rc = amd_mp2_pci_init(privdata, pci_dev);
	if (rc)
		return rc;

	mutex_init(&privdata->c2p_lock);

	pm_runtime_set_autosuspend_delay(&pci_dev->dev, 1000);
	pm_runtime_use_autosuspend(&pci_dev->dev);
	pm_runtime_put_autosuspend(&pci_dev->dev);
	pm_runtime_allow(&pci_dev->dev);

	privdata->probed = true;

	dev_info(&pci_dev->dev, "MP2 device registered.\n");
	return 0;
}

static void amd_mp2_pci_remove(struct pci_dev *pci_dev)
{
	struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev);

	pm_runtime_forbid(&pci_dev->dev);
	pm_runtime_get_noresume(&pci_dev->dev);

	pci_intx(pci_dev, 0);
	pci_clear_master(pci_dev);

	amd_mp2_clear_reg(privdata);
}

#ifdef CONFIG_PM
static int amd_mp2_pci_suspend(struct device *dev)
{
	struct pci_dev *pci_dev = to_pci_dev(dev);
	struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev);
	struct amd_i2c_common *i2c_common;
	unsigned int bus_id;
	int ret = 0;

	for (bus_id = 0; bus_id < 2; bus_id++) {
		i2c_common = privdata->busses[bus_id];
		if (i2c_common)
			i2c_common->suspend(i2c_common);
	}

	ret = pci_save_state(pci_dev);
	if (ret) {
		dev_err(ndev_dev(privdata),
			"pci_save_state failed = %d\n", ret);
		return ret;
	}

	pci_disable_device(pci_dev);
	return ret;
}

static int amd_mp2_pci_resume(struct device *dev)
{
	struct pci_dev *pci_dev = to_pci_dev(dev);
	struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev);
	struct amd_i2c_common *i2c_common;
	unsigned int bus_id;
	int ret = 0;

	pci_restore_state(pci_dev);
	ret = pci_enable_device(pci_dev);
	if (ret < 0) {
		dev_err(ndev_dev(privdata),
			"pci_enable_device failed = %d\n", ret);
		return ret;
	}

	for (bus_id = 0; bus_id < 2; bus_id++) {
		i2c_common = privdata->busses[bus_id];
		if (i2c_common) {
			ret = i2c_common->resume(i2c_common);
			if (ret < 0)
				return ret;
		}
	}

	return ret;
}

static UNIVERSAL_DEV_PM_OPS(amd_mp2_pci_pm_ops, amd_mp2_pci_suspend,
			    amd_mp2_pci_resume, NULL);
#endif /* CONFIG_PM */

static const struct pci_device_id amd_mp2_pci_tbl[] = {
	{PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)},
	{0}
};
MODULE_DEVICE_TABLE(pci, amd_mp2_pci_tbl);

static struct pci_driver amd_mp2_pci_driver = {
	.name		= "i2c_amd_mp2",
	.id_table	= amd_mp2_pci_tbl,
	.probe		= amd_mp2_pci_probe,
	.remove		= amd_mp2_pci_remove,
#ifdef CONFIG_PM
	.driver = {
		.pm	= &amd_mp2_pci_pm_ops,
	},
#endif
};
module_pci_driver(amd_mp2_pci_driver);

struct amd_mp2_dev *amd_mp2_find_device(void)
{
	struct device *dev;
	struct pci_dev *pci_dev;

	dev = driver_find_next_device(&amd_mp2_pci_driver.driver, NULL);
	if (!dev)
		return NULL;

	pci_dev = to_pci_dev(dev);
	return (struct amd_mp2_dev *)pci_get_drvdata(pci_dev);
}
EXPORT_SYMBOL_GPL(amd_mp2_find_device);

MODULE_DESCRIPTION("AMD(R) PCI-E MP2 I2C Controller Driver");
MODULE_AUTHOR("Shyam Sundar S K <Shyam-sundar.S-k@amd.com>");
MODULE_AUTHOR("Elie Morisse <syniurge@gmail.com>");
MODULE_LICENSE("Dual BSD/GPL");
Commit	Line	Data
529766e0 EM	1	// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
	2	/*
	3	* AMD MP2 PCIe communication driver
	4	*
	5	* Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
	6	* Elie Morisse <syniurge@gmail.com>
	7	*/
	8
	9	#include <linux/dma-mapping.h>
	10	#include <linux/interrupt.h>
	11	#include <linux/module.h>
	12	#include <linux/pci.h>
	13	#include <linux/slab.h>
	14
	15	#include "i2c-amd-mp2.h"
	16
	17	#include <linux/io-64-nonatomic-lo-hi.h>
	18
	19	static void amd_mp2_c2p_mutex_lock(struct amd_i2c_common *i2c_common)
	20	{
	21	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	22
	23	/* there is only one data mailbox for two i2c adapters */
	24	mutex_lock(&privdata->c2p_lock);
	25	privdata->c2p_lock_busid = i2c_common->bus_id;
	26	}
	27
	28	static void amd_mp2_c2p_mutex_unlock(struct amd_i2c_common *i2c_common)
	29	{
	30	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	31
	32	if (unlikely(privdata->c2p_lock_busid != i2c_common->bus_id)) {
	33	dev_warn(ndev_dev(privdata),
	34	"bus %d attempting to unlock C2P locked by bus %d\n",
	35	i2c_common->bus_id, privdata->c2p_lock_busid);
	36	return;
	37	}
	38
	39	mutex_unlock(&privdata->c2p_lock);
	40	}
	41
	42	static int amd_mp2_cmd(struct amd_i2c_common *i2c_common,
	43	union i2c_cmd_base i2c_cmd_base)
	44	{
	45	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	46	void __iomem *reg;
	47
	48	i2c_common->reqcmd = i2c_cmd_base.s.i2c_cmd;
	49
	50	reg = privdata->mmio + ((i2c_cmd_base.s.bus_id == 1) ?
	51	AMD_C2P_MSG1 : AMD_C2P_MSG0);
	52	writel(i2c_cmd_base.ul, reg);
	53
	54	return 0;
	55	}
	56
	57	int amd_mp2_bus_enable_set(struct amd_i2c_common *i2c_common, bool enable)
	58	{
	59	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
	60	union i2c_cmd_base i2c_cmd_base;
	61
	62	dev_dbg(ndev_dev(privdata), "%s id: %d\n", __func__,
	63	i2c_common->bus_id);
	64
65	i2c_cmd_base.ul = 0;
66	i2c_cmd_base.s.i2c_cmd = enable ? i2c_enable : i2c_disable;
67	i2c_cmd_base.s.bus_id = i2c_common->bus_id;
68	i2c_cmd_base.s.i2c_speed = i2c_common->i2c_speed;
69
70	amd_mp2_c2p_mutex_lock(i2c_common);
71
72	return amd_mp2_cmd(i2c_common, i2c_cmd_base);
73	}
74	EXPORT_SYMBOL_GPL(amd_mp2_bus_enable_set);
75
76	static void amd_mp2_cmd_rw_fill(struct amd_i2c_common *i2c_common,
77	union i2c_cmd_base *i2c_cmd_base,
78	enum i2c_cmd reqcmd)
79	{
80	i2c_cmd_base->s.i2c_cmd = reqcmd;
81	i2c_cmd_base->s.bus_id = i2c_common->bus_id;
82	i2c_cmd_base->s.i2c_speed = i2c_common->i2c_speed;
83	i2c_cmd_base->s.slave_addr = i2c_common->msg->addr;
84	i2c_cmd_base->s.length = i2c_common->msg->len;
85	}
86
87	int amd_mp2_rw(struct amd_i2c_common *i2c_common, enum i2c_cmd reqcmd)
88	{
89	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
90	union i2c_cmd_base i2c_cmd_base;
91
92	amd_mp2_cmd_rw_fill(i2c_common, &i2c_cmd_base, reqcmd);
93	amd_mp2_c2p_mutex_lock(i2c_common);
94
95	if (i2c_common->msg->len <= 32) {
96	i2c_cmd_base.s.mem_type = use_c2pmsg;
97	if (reqcmd == i2c_write)
98	memcpy_toio(privdata->mmio + AMD_C2P_MSG2,
99	i2c_common->msg->buf,
100	i2c_common->msg->len);
101	} else {
102	i2c_cmd_base.s.mem_type = use_dram;
103	writeq((u64)i2c_common->dma_addr,
104	privdata->mmio + AMD_C2P_MSG2);
105	}
106
107	return amd_mp2_cmd(i2c_common, i2c_cmd_base);
108	}
109	EXPORT_SYMBOL_GPL(amd_mp2_rw);
110
111	static void amd_mp2_pci_check_rw_event(struct amd_i2c_common *i2c_common)
112	{
113	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
114	int len = i2c_common->eventval.r.length;
115	u32 slave_addr = i2c_common->eventval.r.slave_addr;
116	bool err = false;
117
118	if (unlikely(len != i2c_common->msg->len)) {
119	dev_err(ndev_dev(privdata),
120	"length %d in event doesn't match buffer length %d!\n",
121	len, i2c_common->msg->len);
122	err = true;
123	}
124
125	if (unlikely(slave_addr != i2c_common->msg->addr)) {
126	dev_err(ndev_dev(privdata),
127	"unexpected slave address %x (expected: %x)!\n",
128	slave_addr, i2c_common->msg->addr);
129	err = true;
130	}
131
132	if (!err)
133	i2c_common->cmd_success = true;
134	}
135
136	static void __amd_mp2_process_event(struct amd_i2c_common *i2c_common)
137	{
138	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
139	enum status_type sts = i2c_common->eventval.r.status;
140	enum response_type res = i2c_common->eventval.r.response;
141	int len = i2c_common->eventval.r.length;
142
143	if (res != command_success) {
144	if (res != command_failed)
145	dev_err(ndev_dev(privdata), "invalid response to i2c command!\n");
146	return;
147	}
148
149	switch (i2c_common->reqcmd) {
150	case i2c_read:
151	if (sts == i2c_readcomplete_event) {
152	amd_mp2_pci_check_rw_event(i2c_common);
153	if (len <= 32)
154	memcpy_fromio(i2c_common->msg->buf,
155	privdata->mmio + AMD_C2P_MSG2,
156	len);
157	} else if (sts != i2c_readfail_event) {
158	dev_err(ndev_dev(privdata),
159	"invalid i2c status after read (%d)!\n", sts);
160	}
161	break;
162	case i2c_write:
163	if (sts == i2c_writecomplete_event)
164	amd_mp2_pci_check_rw_event(i2c_common);
165	else if (sts != i2c_writefail_event)
166	dev_err(ndev_dev(privdata),
167	"invalid i2c status after write (%d)!\n", sts);
168	break;
169	case i2c_enable:
170	if (sts == i2c_busenable_complete)
171	i2c_common->cmd_success = true;
172	else if (sts != i2c_busenable_failed)
173	dev_err(ndev_dev(privdata),
174	"invalid i2c status after bus enable (%d)!\n",
175	sts);
176	break;
177	case i2c_disable:
178	if (sts == i2c_busdisable_complete)
179	i2c_common->cmd_success = true;
180	else if (sts != i2c_busdisable_failed)
181	dev_err(ndev_dev(privdata),
182	"invalid i2c status after bus disable (%d)!\n",
183	sts);
184	break;
185	default:
186	break;
187	}
188	}
189
190	void amd_mp2_process_event(struct amd_i2c_common *i2c_common)
191	{
192	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
193
194	if (unlikely(i2c_common->reqcmd == i2c_none)) {
195	dev_warn(ndev_dev(privdata),
196	"received msg but no cmd was sent (bus = %d)!\n",
197	i2c_common->bus_id);
198	return;
199	}
200
201	__amd_mp2_process_event(i2c_common);
202
203	i2c_common->reqcmd = i2c_none;
204	amd_mp2_c2p_mutex_unlock(i2c_common);
205	}
206	EXPORT_SYMBOL_GPL(amd_mp2_process_event);
207
208	static irqreturn_t amd_mp2_irq_isr(int irq, void *dev)
209	{
210	struct amd_mp2_dev *privdata = dev;
211	struct amd_i2c_common *i2c_common;
212	u32 val;
213	unsigned int bus_id;
214	void __iomem *reg;
215	enum irqreturn ret = IRQ_NONE;
216
217	for (bus_id = 0; bus_id < 2; bus_id++) {
218	i2c_common = privdata->busses[bus_id];
219	if (!i2c_common)
220	continue;
221
222	reg = privdata->mmio + ((bus_id == 0) ?
223	AMD_P2C_MSG1 : AMD_P2C_MSG2);
224	val = readl(reg);
225	if (val != 0) {
226	writel(0, reg);
227	writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
228	i2c_common->eventval.ul = val;
229	i2c_common->cmd_completion(i2c_common);
230
231	ret = IRQ_HANDLED;
232	}
233	}
234
235	if (ret != IRQ_HANDLED) {
236	val = readl(privdata->mmio + AMD_P2C_MSG_INTEN);
237	if (val != 0) {
238	writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
239	dev_warn(ndev_dev(privdata),
240	"received irq without message\n");
241	ret = IRQ_HANDLED;
242	}
243	}
244
245	return ret;
246	}
247
248	void amd_mp2_rw_timeout(struct amd_i2c_common *i2c_common)
249	{
250	i2c_common->reqcmd = i2c_none;
251	amd_mp2_c2p_mutex_unlock(i2c_common);
252	}
253	EXPORT_SYMBOL_GPL(amd_mp2_rw_timeout);
254
255	int amd_mp2_register_cb(struct amd_i2c_common *i2c_common)
256	{
257	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
258
259	if (i2c_common->bus_id > 1)
260	return -EINVAL;
261
262	if (privdata->busses[i2c_common->bus_id]) {
263	dev_err(ndev_dev(privdata),
264	"Bus %d already taken!\n", i2c_common->bus_id);
265	return -EINVAL;
266	}
267
268	privdata->busses[i2c_common->bus_id] = i2c_common;
269
270	return 0;
271	}
272	EXPORT_SYMBOL_GPL(amd_mp2_register_cb);
273
274	int amd_mp2_unregister_cb(struct amd_i2c_common *i2c_common)
275	{
276	struct amd_mp2_dev *privdata = i2c_common->mp2_dev;
277
278	privdata->busses[i2c_common->bus_id] = NULL;
279
280	return 0;
281	}
282	EXPORT_SYMBOL_GPL(amd_mp2_unregister_cb);
283
284	static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata)
285	{
286	int reg;
287
288	for (reg = AMD_C2P_MSG0; reg <= AMD_C2P_MSG9; reg += 4)
289	writel(0, privdata->mmio + reg);
290
291	for (reg = AMD_P2C_MSG1; reg <= AMD_P2C_MSG2; reg += 4)
292	writel(0, privdata->mmio + reg);
293	}
294
295	static int amd_mp2_pci_init(struct amd_mp2_dev *privdata,
296	struct pci_dev *pci_dev)
297	{
298	int rc;
299
300	pci_set_drvdata(pci_dev, privdata);
301
302	rc = pcim_enable_device(pci_dev);
303	if (rc) {
304	dev_err(ndev_dev(privdata), "Failed to enable MP2 PCI device\n");
305	goto err_pci_enable;
306	}
307
308	rc = pcim_iomap_regions(pci_dev, 1 << 2, pci_name(pci_dev));
309	if (rc) {
310	dev_err(ndev_dev(privdata), "I/O memory remapping failed\n");
311	goto err_pci_enable;
312	}
313	privdata->mmio = pcim_iomap_table(pci_dev)[2];
314
315	pci_set_master(pci_dev);
316
317	rc = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(64));
318	if (rc) {
319	rc = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(32));
320	if (rc)
321	goto err_dma_mask;
322	}
323
324	/* Set up intx irq */
325	writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
326	pci_intx(pci_dev, 1);
327	rc = devm_request_irq(&pci_dev->dev, pci_dev->irq, amd_mp2_irq_isr,
328	IRQF_SHARED, dev_name(&pci_dev->dev), privdata);
329	if (rc)
330	dev_err(&pci_dev->dev, "Failure requesting irq %i: %d\n",
331	pci_dev->irq, rc);
332
333	return rc;
334
335	err_dma_mask:
336	pci_clear_master(pci_dev);
337	err_pci_enable:
338	pci_set_drvdata(pci_dev, NULL);
339	return rc;
340	}
341
342	static int amd_mp2_pci_probe(struct pci_dev *pci_dev,
343	const struct pci_device_id *id)
344	{
345	struct amd_mp2_dev *privdata;
346	int rc;
347
348	privdata = devm_kzalloc(&pci_dev->dev, sizeof(*privdata), GFP_KERNEL);
349	if (!privdata)
350	return -ENOMEM;
351
ac2b0813	352	privdata->pci_dev = pci_dev;
529766e0 EM	353	rc = amd_mp2_pci_init(privdata, pci_dev);
	354	if (rc)
	355	return rc;
	356
	357	mutex_init(&privdata->c2p_lock);
529766e0 EM	358
	359	pm_runtime_set_autosuspend_delay(&pci_dev->dev, 1000);
	360	pm_runtime_use_autosuspend(&pci_dev->dev);
	361	pm_runtime_put_autosuspend(&pci_dev->dev);
	362	pm_runtime_allow(&pci_dev->dev);
	363
	364	privdata->probed = true;
	365
	366	dev_info(&pci_dev->dev, "MP2 device registered.\n");
	367	return 0;
	368	}
	369
	370	static void amd_mp2_pci_remove(struct pci_dev *pci_dev)
	371	{
	372	struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev);
	373
	374	pm_runtime_forbid(&pci_dev->dev);
	375	pm_runtime_get_noresume(&pci_dev->dev);
	376
	377	pci_intx(pci_dev, 0);
	378	pci_clear_master(pci_dev);
	379
	380	amd_mp2_clear_reg(privdata);
	381	}
	382
	383	#ifdef CONFIG_PM
	384	static int amd_mp2_pci_suspend(struct device *dev)
	385	{
	386	struct pci_dev *pci_dev = to_pci_dev(dev);
	387	struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev);
	388	struct amd_i2c_common *i2c_common;
	389	unsigned int bus_id;
	390	int ret = 0;
	391
	392	for (bus_id = 0; bus_id < 2; bus_id++) {
	393	i2c_common = privdata->busses[bus_id];
	394	if (i2c_common)
	395	i2c_common->suspend(i2c_common);
	396	}
	397
	398	ret = pci_save_state(pci_dev);
	399	if (ret) {
	400	dev_err(ndev_dev(privdata),
	401	"pci_save_state failed = %d\n", ret);
	402	return ret;
	403	}
	404
	405	pci_disable_device(pci_dev);
	406	return ret;
	407	}
	408
	409	static int amd_mp2_pci_resume(struct device *dev)
	410	{
	411	struct pci_dev *pci_dev = to_pci_dev(dev);
	412	struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev);
	413	struct amd_i2c_common *i2c_common;
	414	unsigned int bus_id;
	415	int ret = 0;
	416
	417	pci_restore_state(pci_dev);
	418	ret = pci_enable_device(pci_dev);
	419	if (ret < 0) {
	420	dev_err(ndev_dev(privdata),
	421	"pci_enable_device failed = %d\n", ret);
422	return ret;
423	}
424
425	for (bus_id = 0; bus_id < 2; bus_id++) {
426	i2c_common = privdata->busses[bus_id];
427	if (i2c_common) {
428	ret = i2c_common->resume(i2c_common);
429	if (ret < 0)
430	return ret;
431	}
432	}
433
434	return ret;
435	}
436
437	static UNIVERSAL_DEV_PM_OPS(amd_mp2_pci_pm_ops, amd_mp2_pci_suspend,
438	amd_mp2_pci_resume, NULL);
439	#endif /* CONFIG_PM */
440
441	static const struct pci_device_id amd_mp2_pci_tbl[] = {
442	{PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)},
443	{0}
444	};
445	MODULE_DEVICE_TABLE(pci, amd_mp2_pci_tbl);
446
447	static struct pci_driver amd_mp2_pci_driver = {
448	.name = "i2c_amd_mp2",
449	.id_table = amd_mp2_pci_tbl,
450	.probe = amd_mp2_pci_probe,
451	.remove = amd_mp2_pci_remove,
452	#ifdef CONFIG_PM
453	.driver = {
454	.pm = &amd_mp2_pci_pm_ops,
455	},
456	#endif
457	};
458	module_pci_driver(amd_mp2_pci_driver);
459
529766e0 EM	460	struct amd_mp2_dev *amd_mp2_find_device(void)
	461	{
	462	struct device *dev;
	463	struct pci_dev *pci_dev;
	464
6bf85ba9	465	dev = driver_find_next_device(&amd_mp2_pci_driver.driver, NULL);
529766e0 EM	466	if (!dev)
	467	return NULL;
	468
	469	pci_dev = to_pci_dev(dev);
	470	return (struct amd_mp2_dev *)pci_get_drvdata(pci_dev);
	471	}
	472	EXPORT_SYMBOL_GPL(amd_mp2_find_device);
	473
	474	MODULE_DESCRIPTION("AMD(R) PCI-E MP2 I2C Controller Driver");
	475	MODULE_AUTHOR("Shyam Sundar S K <Shyam-sundar.S-k@amd.com>");
	476	MODULE_AUTHOR("Elie Morisse <syniurge@gmail.com>");
	477	MODULE_LICENSE("Dual BSD/GPL");