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 #include <linux/phy/phy.h>
10 
11 #include "m_can.h"
12 
13 struct m_can_plat_priv {
14 	struct m_can_classdev cdev;
15 
16 	void __iomem *base;
17 	void __iomem *mram_base;
18 };
19 
20 static inline struct m_can_plat_priv *cdev_to_priv(struct m_can_classdev *cdev)
21 {
22 	return container_of(cdev, struct m_can_plat_priv, cdev);
23 }
24 
25 static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
26 {
27 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
28 
29 	return readl(priv->base + reg);
30 }
31 
32 static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
33 {
34 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
35 
36 	ioread32_rep(priv->mram_base + offset, val, val_count);
37 
38 	return 0;
39 }
40 
41 static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val)
42 {
43 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
44 
45 	writel(val, priv->base + reg);
46 
47 	return 0;
48 }
49 
50 static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
51 			    const void *val, size_t val_count)
52 {
53 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
54 
55 	iowrite32_rep(priv->base + offset, val, val_count);
56 
57 	return 0;
58 }
59 
60 static struct m_can_ops m_can_plat_ops = {
61 	.read_reg = iomap_read_reg,
62 	.write_reg = iomap_write_reg,
63 	.write_fifo = iomap_write_fifo,
64 	.read_fifo = iomap_read_fifo,
65 };
66 
67 static int m_can_plat_probe(struct platform_device *pdev)
68 {
69 	struct m_can_classdev *mcan_class;
70 	struct m_can_plat_priv *priv;
71 	struct resource *res;
72 	void __iomem *addr;
73 	void __iomem *mram_addr;
74 	struct phy *transceiver;
75 	int irq, ret = 0;
76 
77 	mcan_class = m_can_class_allocate_dev(&pdev->dev,
78 					      sizeof(struct m_can_plat_priv));
79 	if (!mcan_class)
80 		return -ENOMEM;
81 
82 	priv = cdev_to_priv(mcan_class);
83 
84 	ret = m_can_class_get_clocks(mcan_class);
85 	if (ret)
86 		goto probe_fail;
87 
88 	addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
89 	irq = platform_get_irq_byname(pdev, "int0");
90 	if (IS_ERR(addr) || irq < 0) {
91 		ret = -EINVAL;
92 		goto probe_fail;
93 	}
94 
95 	/* message ram could be shared */
96 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
97 	if (!res) {
98 		ret = -ENODEV;
99 		goto probe_fail;
100 	}
101 
102 	mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
103 	if (!mram_addr) {
104 		ret = -ENOMEM;
105 		goto probe_fail;
106 	}
107 
108 	transceiver = devm_phy_optional_get(&pdev->dev, NULL);
109 	if (IS_ERR(transceiver)) {
110 		ret = PTR_ERR(transceiver);
111 		dev_err_probe(&pdev->dev, ret, "failed to get phy\n");
112 		goto probe_fail;
113 	}
114 
115 	if (transceiver)
116 		mcan_class->can.bitrate_max = transceiver->attrs.max_link_rate;
117 
118 	priv->base = addr;
119 	priv->mram_base = mram_addr;
120 
121 	mcan_class->net->irq = irq;
122 	mcan_class->pm_clock_support = 1;
123 	mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk);
124 	mcan_class->dev = &pdev->dev;
125 	mcan_class->transceiver = transceiver;
126 
127 	mcan_class->ops = &m_can_plat_ops;
128 
129 	mcan_class->is_peripheral = false;
130 
131 	platform_set_drvdata(pdev, mcan_class);
132 
133 	ret = m_can_init_ram(mcan_class);
134 	if (ret)
135 		goto probe_fail;
136 
137 	pm_runtime_enable(mcan_class->dev);
138 	ret = m_can_class_register(mcan_class);
139 	if (ret)
140 		goto out_runtime_disable;
141 
142 	return ret;
143 
144 out_runtime_disable:
145 	pm_runtime_disable(mcan_class->dev);
146 probe_fail:
147 	m_can_class_free_dev(mcan_class->net);
148 	return ret;
149 }
150 
151 static __maybe_unused int m_can_suspend(struct device *dev)
152 {
153 	return m_can_class_suspend(dev);
154 }
155 
156 static __maybe_unused int m_can_resume(struct device *dev)
157 {
158 	return m_can_class_resume(dev);
159 }
160 
161 static int m_can_plat_remove(struct platform_device *pdev)
162 {
163 	struct m_can_plat_priv *priv = platform_get_drvdata(pdev);
164 	struct m_can_classdev *mcan_class = &priv->cdev;
165 
166 	m_can_class_unregister(mcan_class);
167 
168 	m_can_class_free_dev(mcan_class->net);
169 
170 	return 0;
171 }
172 
173 static int __maybe_unused m_can_runtime_suspend(struct device *dev)
174 {
175 	struct m_can_plat_priv *priv = dev_get_drvdata(dev);
176 	struct m_can_classdev *mcan_class = &priv->cdev;
177 
178 	clk_disable_unprepare(mcan_class->cclk);
179 	clk_disable_unprepare(mcan_class->hclk);
180 
181 	return 0;
182 }
183 
184 static int __maybe_unused m_can_runtime_resume(struct device *dev)
185 {
186 	struct m_can_plat_priv *priv = dev_get_drvdata(dev);
187 	struct m_can_classdev *mcan_class = &priv->cdev;
188 	int err;
189 
190 	err = clk_prepare_enable(mcan_class->hclk);
191 	if (err)
192 		return err;
193 
194 	err = clk_prepare_enable(mcan_class->cclk);
195 	if (err)
196 		clk_disable_unprepare(mcan_class->hclk);
197 
198 	return err;
199 }
200 
201 static const struct dev_pm_ops m_can_pmops = {
202 	SET_RUNTIME_PM_OPS(m_can_runtime_suspend,
203 			   m_can_runtime_resume, NULL)
204 	SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
205 };
206 
207 static const struct of_device_id m_can_of_table[] = {
208 	{ .compatible = "bosch,m_can", .data = NULL },
209 	{ /* sentinel */ },
210 };
211 MODULE_DEVICE_TABLE(of, m_can_of_table);
212 
213 static struct platform_driver m_can_plat_driver = {
214 	.driver = {
215 		.name = KBUILD_MODNAME,
216 		.of_match_table = m_can_of_table,
217 		.pm     = &m_can_pmops,
218 	},
219 	.probe = m_can_plat_probe,
220 	.remove = m_can_plat_remove,
221 };
222 
223 module_platform_driver(m_can_plat_driver);
224 
225 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
226 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
227 MODULE_LICENSE("GPL v2");
228 MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers");
229