xref: /openbmc/linux/drivers/net/can/m_can/m_can_pci.c (revision 84b102f5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCI Specific M_CAN Glue
4  *
5  * Copyright (C) 2018-2020 Intel Corporation
6  * Author: Felipe Balbi (Intel)
7  * Author: Jarkko Nikula <jarkko.nikula@linux.intel.com>
8  * Author: Raymond Tan <raymond.tan@intel.com>
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/netdevice.h>
14 #include <linux/pci.h>
15 #include <linux/pm_runtime.h>
16 
17 #include "m_can.h"
18 
19 #define M_CAN_PCI_MMIO_BAR		0
20 
21 #define M_CAN_CLOCK_FREQ_EHL		100000000
22 #define CTL_CSR_INT_CTL_OFFSET		0x508
23 
24 struct m_can_pci_priv {
25 	struct m_can_classdev cdev;
26 
27 	void __iomem *base;
28 };
29 
30 static inline struct m_can_pci_priv *cdev_to_priv(struct m_can_classdev *cdev)
31 {
32 	return container_of(cdev, struct m_can_pci_priv, cdev);
33 }
34 
35 static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
36 {
37 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
38 
39 	return readl(priv->base + reg);
40 }
41 
42 static u32 iomap_read_fifo(struct m_can_classdev *cdev, int offset)
43 {
44 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
45 
46 	return readl(priv->base + offset);
47 }
48 
49 static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val)
50 {
51 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
52 
53 	writel(val, priv->base + reg);
54 
55 	return 0;
56 }
57 
58 static int iomap_write_fifo(struct m_can_classdev *cdev, int offset, int val)
59 {
60 	struct m_can_pci_priv *priv = cdev_to_priv(cdev);
61 
62 	writel(val, priv->base + offset);
63 
64 	return 0;
65 }
66 
67 static struct m_can_ops m_can_pci_ops = {
68 	.read_reg = iomap_read_reg,
69 	.write_reg = iomap_write_reg,
70 	.write_fifo = iomap_write_fifo,
71 	.read_fifo = iomap_read_fifo,
72 };
73 
74 static int m_can_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
75 {
76 	struct device *dev = &pci->dev;
77 	struct m_can_classdev *mcan_class;
78 	struct m_can_pci_priv *priv;
79 	void __iomem *base;
80 	int ret;
81 
82 	ret = pcim_enable_device(pci);
83 	if (ret)
84 		return ret;
85 
86 	pci_set_master(pci);
87 
88 	ret = pcim_iomap_regions(pci, BIT(M_CAN_PCI_MMIO_BAR), pci_name(pci));
89 	if (ret)
90 		return ret;
91 
92 	base = pcim_iomap_table(pci)[M_CAN_PCI_MMIO_BAR];
93 
94 	if (!base) {
95 		dev_err(dev, "failed to map BARs\n");
96 		return -ENOMEM;
97 	}
98 
99 	mcan_class = m_can_class_allocate_dev(&pci->dev,
100 					      sizeof(struct m_can_pci_priv));
101 	if (!mcan_class)
102 		return -ENOMEM;
103 
104 	priv = cdev_to_priv(mcan_class);
105 
106 	priv->base = base;
107 
108 	ret = pci_alloc_irq_vectors(pci, 1, 1, PCI_IRQ_ALL_TYPES);
109 	if (ret < 0)
110 		return ret;
111 
112 	mcan_class->dev = &pci->dev;
113 	mcan_class->net->irq = pci_irq_vector(pci, 0);
114 	mcan_class->pm_clock_support = 1;
115 	mcan_class->can.clock.freq = id->driver_data;
116 	mcan_class->ops = &m_can_pci_ops;
117 
118 	pci_set_drvdata(pci, mcan_class);
119 
120 	ret = m_can_class_register(mcan_class);
121 	if (ret)
122 		goto err;
123 
124 	/* Enable interrupt control at CAN wrapper IP */
125 	writel(0x1, base + CTL_CSR_INT_CTL_OFFSET);
126 
127 	pm_runtime_set_autosuspend_delay(dev, 1000);
128 	pm_runtime_use_autosuspend(dev);
129 	pm_runtime_put_noidle(dev);
130 	pm_runtime_allow(dev);
131 
132 	return 0;
133 
134 err:
135 	pci_free_irq_vectors(pci);
136 	return ret;
137 }
138 
139 static void m_can_pci_remove(struct pci_dev *pci)
140 {
141 	struct m_can_classdev *mcan_class = pci_get_drvdata(pci);
142 	struct m_can_pci_priv *priv = cdev_to_priv(mcan_class);
143 
144 	pm_runtime_forbid(&pci->dev);
145 	pm_runtime_get_noresume(&pci->dev);
146 
147 	/* Disable interrupt control at CAN wrapper IP */
148 	writel(0x0, priv->base + CTL_CSR_INT_CTL_OFFSET);
149 
150 	m_can_class_unregister(mcan_class);
151 	pci_free_irq_vectors(pci);
152 }
153 
154 static __maybe_unused int m_can_pci_suspend(struct device *dev)
155 {
156 	return m_can_class_suspend(dev);
157 }
158 
159 static __maybe_unused int m_can_pci_resume(struct device *dev)
160 {
161 	return m_can_class_resume(dev);
162 }
163 
164 static SIMPLE_DEV_PM_OPS(m_can_pci_pm_ops,
165 			 m_can_pci_suspend, m_can_pci_resume);
166 
167 static const struct pci_device_id m_can_pci_id_table[] = {
168 	{ PCI_VDEVICE(INTEL, 0x4bc1), M_CAN_CLOCK_FREQ_EHL, },
169 	{ PCI_VDEVICE(INTEL, 0x4bc2), M_CAN_CLOCK_FREQ_EHL, },
170 	{  }	/* Terminating Entry */
171 };
172 MODULE_DEVICE_TABLE(pci, m_can_pci_id_table);
173 
174 static struct pci_driver m_can_pci_driver = {
175 	.name = "m_can_pci",
176 	.probe = m_can_pci_probe,
177 	.remove = m_can_pci_remove,
178 	.id_table = m_can_pci_id_table,
179 	.driver = {
180 		.pm = &m_can_pci_pm_ops,
181 	},
182 };
183 
184 module_pci_driver(m_can_pci_driver);
185 
186 MODULE_AUTHOR("Felipe Balbi (Intel)");
187 MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
188 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
189 MODULE_LICENSE("GPL");
190 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller on PCI bus");
191