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 		ret = -ENOMEM;
72 		goto probe_fail;
73 	}
74 
75 	mcan_class->device_data = priv;
76 
77 	ret = m_can_class_get_clocks(mcan_class);
78 	if (ret)
79 		goto probe_fail;
80 
81 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "m_can");
82 	addr = devm_ioremap_resource(&pdev->dev, res);
83 	irq = platform_get_irq_byname(pdev, "int0");
84 	if (IS_ERR(addr) || irq < 0) {
85 		ret = -EINVAL;
86 		goto probe_fail;
87 	}
88 
89 	/* message ram could be shared */
90 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
91 	if (!res) {
92 		ret = -ENODEV;
93 		goto probe_fail;
94 	}
95 
96 	mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
97 	if (!mram_addr) {
98 		ret = -ENOMEM;
99 		goto probe_fail;
100 	}
101 
102 	priv->base = addr;
103 	priv->mram_base = mram_addr;
104 
105 	mcan_class->net->irq = irq;
106 	mcan_class->pm_clock_support = 1;
107 	mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk);
108 	mcan_class->dev = &pdev->dev;
109 
110 	mcan_class->ops = &m_can_plat_ops;
111 
112 	mcan_class->is_peripheral = false;
113 
114 	platform_set_drvdata(pdev, mcan_class->net);
115 
116 	m_can_init_ram(mcan_class);
117 
118 	return m_can_class_register(mcan_class);
119 
120 probe_fail:
121 	m_can_class_free_dev(mcan_class->net);
122 	return ret;
123 }
124 
125 static __maybe_unused int m_can_suspend(struct device *dev)
126 {
127 	return m_can_class_suspend(dev);
128 }
129 
130 static __maybe_unused int m_can_resume(struct device *dev)
131 {
132 	return m_can_class_resume(dev);
133 }
134 
135 static int m_can_plat_remove(struct platform_device *pdev)
136 {
137 	struct net_device *dev = platform_get_drvdata(pdev);
138 	struct m_can_classdev *mcan_class = netdev_priv(dev);
139 
140 	m_can_class_unregister(mcan_class);
141 
142 	m_can_class_free_dev(mcan_class->net);
143 
144 	platform_set_drvdata(pdev, NULL);
145 
146 	return 0;
147 }
148 
149 static int __maybe_unused m_can_runtime_suspend(struct device *dev)
150 {
151 	struct net_device *ndev = dev_get_drvdata(dev);
152 	struct m_can_classdev *mcan_class = netdev_priv(ndev);
153 
154 	clk_disable_unprepare(mcan_class->cclk);
155 	clk_disable_unprepare(mcan_class->hclk);
156 
157 	return 0;
158 }
159 
160 static int __maybe_unused m_can_runtime_resume(struct device *dev)
161 {
162 	struct net_device *ndev = dev_get_drvdata(dev);
163 	struct m_can_classdev *mcan_class = netdev_priv(ndev);
164 	int err;
165 
166 	err = clk_prepare_enable(mcan_class->hclk);
167 	if (err)
168 		return err;
169 
170 	err = clk_prepare_enable(mcan_class->cclk);
171 	if (err)
172 		clk_disable_unprepare(mcan_class->hclk);
173 
174 	return err;
175 }
176 
177 static const struct dev_pm_ops m_can_pmops = {
178 	SET_RUNTIME_PM_OPS(m_can_runtime_suspend,
179 			   m_can_runtime_resume, NULL)
180 	SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
181 };
182 
183 static const struct of_device_id m_can_of_table[] = {
184 	{ .compatible = "bosch,m_can", .data = NULL },
185 	{ /* sentinel */ },
186 };
187 MODULE_DEVICE_TABLE(of, m_can_of_table);
188 
189 static struct platform_driver m_can_plat_driver = {
190 	.driver = {
191 		.name = KBUILD_MODNAME,
192 		.of_match_table = m_can_of_table,
193 		.pm     = &m_can_pmops,
194 	},
195 	.probe = m_can_plat_probe,
196 	.remove = m_can_plat_remove,
197 };
198 
199 module_platform_driver(m_can_plat_driver);
200 
201 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
202 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
203 MODULE_LICENSE("GPL v2");
204 MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers");
205