1 // SPDX-License-Identifier: GPL-2.0
2 // IOMapped CAN bus driver for Bosch M_CAN controller
3 // Copyright (C) 2014 Freescale Semiconductor, Inc.
4 //	Dong Aisheng <b29396@freescale.com>
5 //
6 // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/
7 
8 #include <linux/platform_device.h>
9 
10 #include "m_can.h"
11 
12 struct m_can_plat_priv {
13 	void __iomem *base;
14 	void __iomem *mram_base;
15 };
16 
17 static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
18 {
19 	struct m_can_plat_priv *priv = cdev->device_data;
20 
21 	return readl(priv->base + reg);
22 }
23 
24 static u32 iomap_read_fifo(struct m_can_classdev *cdev, int offset)
25 {
26 	struct m_can_plat_priv *priv = cdev->device_data;
27 
28 	return readl(priv->mram_base + offset);
29 }
30 
31 static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val)
32 {
33 	struct m_can_plat_priv *priv = cdev->device_data;
34 
35 	writel(val, priv->base + reg);
36 
37 	return 0;
38 }
39 
40 static int iomap_write_fifo(struct m_can_classdev *cdev, int offset, int val)
41 {
42 	struct m_can_plat_priv *priv = cdev->device_data;
43 
44 	writel(val, priv->mram_base + offset);
45 
46 	return 0;
47 }
48 
49 static struct m_can_ops m_can_plat_ops = {
50 	.read_reg = iomap_read_reg,
51 	.write_reg = iomap_write_reg,
52 	.write_fifo = iomap_write_fifo,
53 	.read_fifo = iomap_read_fifo,
54 };
55 
56 static int m_can_plat_probe(struct platform_device *pdev)
57 {
58 	struct m_can_classdev *mcan_class;
59 	struct m_can_plat_priv *priv;
60 	struct resource *res;
61 	void __iomem *addr;
62 	void __iomem *mram_addr;
63 	int irq, ret = 0;
64 
65 	mcan_class = m_can_class_allocate_dev(&pdev->dev);
66 	if (!mcan_class)
67 		return -ENOMEM;
68 
69 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
70 	if (!priv)
71 		return -ENOMEM;
72 
73 	mcan_class->device_data = priv;
74 
75 	m_can_class_get_clocks(mcan_class);
76 
77 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "m_can");
78 	addr = devm_ioremap_resource(&pdev->dev, res);
79 	irq = platform_get_irq_byname(pdev, "int0");
80 	if (IS_ERR(addr) || irq < 0) {
81 		ret = -EINVAL;
82 		goto failed_ret;
83 	}
84 
85 	/* message ram could be shared */
86 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
87 	if (!res) {
88 		ret = -ENODEV;
89 		goto failed_ret;
90 	}
91 
92 	mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
93 	if (!mram_addr) {
94 		ret = -ENOMEM;
95 		goto failed_ret;
96 	}
97 
98 	priv->base = addr;
99 	priv->mram_base = mram_addr;
100 
101 	mcan_class->net->irq = irq;
102 	mcan_class->pm_clock_support = 1;
103 	mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk);
104 	mcan_class->dev = &pdev->dev;
105 
106 	mcan_class->ops = &m_can_plat_ops;
107 
108 	mcan_class->is_peripheral = false;
109 
110 	platform_set_drvdata(pdev, mcan_class->dev);
111 
112 	m_can_init_ram(mcan_class);
113 
114 	ret = m_can_class_register(mcan_class);
115 
116 failed_ret:
117 	return ret;
118 }
119 
120 static __maybe_unused int m_can_suspend(struct device *dev)
121 {
122 	return m_can_class_suspend(dev);
123 }
124 
125 static __maybe_unused int m_can_resume(struct device *dev)
126 {
127 	return m_can_class_resume(dev);
128 }
129 
130 static int m_can_plat_remove(struct platform_device *pdev)
131 {
132 	struct net_device *dev = platform_get_drvdata(pdev);
133 	struct m_can_classdev *mcan_class = netdev_priv(dev);
134 
135 	m_can_class_unregister(mcan_class);
136 
137 	platform_set_drvdata(pdev, NULL);
138 
139 	return 0;
140 }
141 
142 static int __maybe_unused m_can_runtime_suspend(struct device *dev)
143 {
144 	struct net_device *ndev = dev_get_drvdata(dev);
145 	struct m_can_classdev *mcan_class = netdev_priv(ndev);
146 
147 	m_can_class_suspend(dev);
148 
149 	clk_disable_unprepare(mcan_class->cclk);
150 	clk_disable_unprepare(mcan_class->hclk);
151 
152 	return 0;
153 }
154 
155 static int __maybe_unused m_can_runtime_resume(struct device *dev)
156 {
157 	struct net_device *ndev = dev_get_drvdata(dev);
158 	struct m_can_classdev *mcan_class = netdev_priv(ndev);
159 	int err;
160 
161 	err = clk_prepare_enable(mcan_class->hclk);
162 	if (err)
163 		return err;
164 
165 	err = clk_prepare_enable(mcan_class->cclk);
166 	if (err)
167 		clk_disable_unprepare(mcan_class->hclk);
168 
169 	m_can_class_resume(dev);
170 
171 	return err;
172 }
173 
174 static const struct dev_pm_ops m_can_pmops = {
175 	SET_RUNTIME_PM_OPS(m_can_runtime_suspend,
176 			   m_can_runtime_resume, NULL)
177 	SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
178 };
179 
180 static const struct of_device_id m_can_of_table[] = {
181 	{ .compatible = "bosch,m_can", .data = NULL },
182 	{ /* sentinel */ },
183 };
184 MODULE_DEVICE_TABLE(of, m_can_of_table);
185 
186 static struct platform_driver m_can_plat_driver = {
187 	.driver = {
188 		.name = KBUILD_MODNAME,
189 		.of_match_table = m_can_of_table,
190 		.pm     = &m_can_pmops,
191 	},
192 	.probe = m_can_plat_probe,
193 	.remove = m_can_plat_remove,
194 };
195 
196 module_platform_driver(m_can_plat_driver);
197 
198 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
199 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
200 MODULE_LICENSE("GPL v2");
201 MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers");
202