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/hrtimer.h>
9 #include <linux/phy/phy.h>
10 #include <linux/platform_device.h>
11
12 #include "m_can.h"
13
14 struct m_can_plat_priv {
15 struct m_can_classdev cdev;
16
17 void __iomem *base;
18 void __iomem *mram_base;
19 };
20
cdev_to_priv(struct m_can_classdev * cdev)21 static inline struct m_can_plat_priv *cdev_to_priv(struct m_can_classdev *cdev)
22 {
23 return container_of(cdev, struct m_can_plat_priv, cdev);
24 }
25
iomap_read_reg(struct m_can_classdev * cdev,int reg)26 static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
27 {
28 struct m_can_plat_priv *priv = cdev_to_priv(cdev);
29
30 return readl(priv->base + reg);
31 }
32
iomap_read_fifo(struct m_can_classdev * cdev,int offset,void * val,size_t val_count)33 static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
34 {
35 struct m_can_plat_priv *priv = cdev_to_priv(cdev);
36 void __iomem *src = priv->mram_base + offset;
37
38 while (val_count--) {
39 *(unsigned int *)val = ioread32(src);
40 val += 4;
41 src += 4;
42 }
43
44 return 0;
45 }
46
iomap_write_reg(struct m_can_classdev * cdev,int reg,int val)47 static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val)
48 {
49 struct m_can_plat_priv *priv = cdev_to_priv(cdev);
50
51 writel(val, priv->base + reg);
52
53 return 0;
54 }
55
iomap_write_fifo(struct m_can_classdev * cdev,int offset,const void * val,size_t val_count)56 static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
57 const void *val, size_t val_count)
58 {
59 struct m_can_plat_priv *priv = cdev_to_priv(cdev);
60 void __iomem *dst = priv->mram_base + offset;
61
62 while (val_count--) {
63 iowrite32(*(unsigned int *)val, dst);
64 val += 4;
65 dst += 4;
66 }
67
68 return 0;
69 }
70
71 static const struct m_can_ops m_can_plat_ops = {
72 .read_reg = iomap_read_reg,
73 .write_reg = iomap_write_reg,
74 .write_fifo = iomap_write_fifo,
75 .read_fifo = iomap_read_fifo,
76 };
77
m_can_plat_probe(struct platform_device * pdev)78 static int m_can_plat_probe(struct platform_device *pdev)
79 {
80 struct m_can_classdev *mcan_class;
81 struct m_can_plat_priv *priv;
82 struct resource *res;
83 void __iomem *addr;
84 void __iomem *mram_addr;
85 struct phy *transceiver;
86 int irq = 0, ret = 0;
87
88 mcan_class = m_can_class_allocate_dev(&pdev->dev,
89 sizeof(struct m_can_plat_priv));
90 if (!mcan_class)
91 return -ENOMEM;
92
93 priv = cdev_to_priv(mcan_class);
94
95 ret = m_can_class_get_clocks(mcan_class);
96 if (ret)
97 goto probe_fail;
98
99 addr = devm_platform_ioremap_resource_byname(pdev, "m_can");
100 if (IS_ERR(addr)) {
101 ret = PTR_ERR(addr);
102 goto probe_fail;
103 }
104
105 if (device_property_present(mcan_class->dev, "interrupts") ||
106 device_property_present(mcan_class->dev, "interrupt-names")) {
107 irq = platform_get_irq_byname(pdev, "int0");
108 if (irq < 0) {
109 ret = irq;
110 goto probe_fail;
111 }
112 }
113
114 /* message ram could be shared */
115 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
116 if (!res) {
117 ret = -ENODEV;
118 goto probe_fail;
119 }
120
121 mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
122 if (!mram_addr) {
123 ret = -ENOMEM;
124 goto probe_fail;
125 }
126
127 transceiver = devm_phy_optional_get(&pdev->dev, NULL);
128 if (IS_ERR(transceiver)) {
129 ret = PTR_ERR(transceiver);
130 dev_err_probe(&pdev->dev, ret, "failed to get phy\n");
131 goto probe_fail;
132 }
133
134 if (transceiver)
135 mcan_class->can.bitrate_max = transceiver->attrs.max_link_rate;
136
137 priv->base = addr;
138 priv->mram_base = mram_addr;
139
140 mcan_class->net->irq = irq;
141 mcan_class->pm_clock_support = 1;
142 mcan_class->pm_wake_source = 0;
143 mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk);
144 mcan_class->dev = &pdev->dev;
145 mcan_class->transceiver = transceiver;
146
147 mcan_class->ops = &m_can_plat_ops;
148
149 mcan_class->is_peripheral = false;
150
151 platform_set_drvdata(pdev, mcan_class);
152
153 pm_runtime_enable(mcan_class->dev);
154 ret = m_can_class_register(mcan_class);
155 if (ret)
156 goto out_runtime_disable;
157
158 return ret;
159
160 out_runtime_disable:
161 pm_runtime_disable(mcan_class->dev);
162 probe_fail:
163 m_can_class_free_dev(mcan_class->net);
164 return ret;
165 }
166
m_can_suspend(struct device * dev)167 static __maybe_unused int m_can_suspend(struct device *dev)
168 {
169 return m_can_class_suspend(dev);
170 }
171
m_can_resume(struct device * dev)172 static __maybe_unused int m_can_resume(struct device *dev)
173 {
174 return m_can_class_resume(dev);
175 }
176
m_can_plat_remove(struct platform_device * pdev)177 static void m_can_plat_remove(struct platform_device *pdev)
178 {
179 struct m_can_plat_priv *priv = platform_get_drvdata(pdev);
180 struct m_can_classdev *mcan_class = &priv->cdev;
181
182 m_can_class_unregister(mcan_class);
183
184 m_can_class_free_dev(mcan_class->net);
185 }
186
m_can_runtime_suspend(struct device * dev)187 static int __maybe_unused m_can_runtime_suspend(struct device *dev)
188 {
189 struct m_can_plat_priv *priv = dev_get_drvdata(dev);
190 struct m_can_classdev *mcan_class = &priv->cdev;
191
192 clk_disable_unprepare(mcan_class->cclk);
193 clk_disable_unprepare(mcan_class->hclk);
194
195 return 0;
196 }
197
m_can_runtime_resume(struct device * dev)198 static int __maybe_unused m_can_runtime_resume(struct device *dev)
199 {
200 struct m_can_plat_priv *priv = dev_get_drvdata(dev);
201 struct m_can_classdev *mcan_class = &priv->cdev;
202 int err;
203
204 err = clk_prepare_enable(mcan_class->hclk);
205 if (err)
206 return err;
207
208 err = clk_prepare_enable(mcan_class->cclk);
209 if (err)
210 clk_disable_unprepare(mcan_class->hclk);
211
212 return err;
213 }
214
215 static const struct dev_pm_ops m_can_pmops = {
216 SET_RUNTIME_PM_OPS(m_can_runtime_suspend,
217 m_can_runtime_resume, NULL)
218 SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
219 };
220
221 static const struct of_device_id m_can_of_table[] = {
222 { .compatible = "bosch,m_can", .data = NULL },
223 { /* sentinel */ },
224 };
225 MODULE_DEVICE_TABLE(of, m_can_of_table);
226
227 static struct platform_driver m_can_plat_driver = {
228 .driver = {
229 .name = KBUILD_MODNAME,
230 .of_match_table = m_can_of_table,
231 .pm = &m_can_pmops,
232 },
233 .probe = m_can_plat_probe,
234 .remove = m_can_plat_remove,
235 };
236
237 module_platform_driver(m_can_plat_driver);
238
239 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
240 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
241 MODULE_LICENSE("GPL v2");
242 MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers");
243