1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2005 Sascha Hauer, Pengutronix
4 * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com>
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/interrupt.h>
10 #include <linux/netdevice.h>
11 #include <linux/delay.h>
12 #include <linux/pci.h>
13 #include <linux/platform_device.h>
14 #include <linux/irq.h>
15 #include <linux/can/dev.h>
16 #include <linux/can/platform/sja1000.h>
17 #include <linux/clk.h>
18 #include <linux/io.h>
19 #include <linux/of.h>
20
21 #include "sja1000.h"
22
23 #define DRV_NAME "sja1000_platform"
24 #define SP_CAN_CLOCK (16000000 / 2)
25
26 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
27 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
28 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
29 MODULE_ALIAS("platform:" DRV_NAME);
30 MODULE_LICENSE("GPL v2");
31
32 struct sja1000_of_data {
33 size_t priv_sz;
34 void (*init)(struct sja1000_priv *priv, struct device_node *of);
35 };
36
37 struct technologic_priv {
38 spinlock_t io_lock;
39 };
40
sp_read_reg8(const struct sja1000_priv * priv,int reg)41 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
42 {
43 return ioread8(priv->reg_base + reg);
44 }
45
sp_write_reg8(const struct sja1000_priv * priv,int reg,u8 val)46 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
47 {
48 iowrite8(val, priv->reg_base + reg);
49 }
50
sp_read_reg16(const struct sja1000_priv * priv,int reg)51 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
52 {
53 return ioread8(priv->reg_base + reg * 2);
54 }
55
sp_write_reg16(const struct sja1000_priv * priv,int reg,u8 val)56 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
57 {
58 iowrite8(val, priv->reg_base + reg * 2);
59 }
60
sp_read_reg32(const struct sja1000_priv * priv,int reg)61 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
62 {
63 return ioread8(priv->reg_base + reg * 4);
64 }
65
sp_write_reg32(const struct sja1000_priv * priv,int reg,u8 val)66 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
67 {
68 iowrite8(val, priv->reg_base + reg * 4);
69 }
70
sp_technologic_read_reg16(const struct sja1000_priv * priv,int reg)71 static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg)
72 {
73 struct technologic_priv *tp = priv->priv;
74 unsigned long flags;
75 u8 val;
76
77 spin_lock_irqsave(&tp->io_lock, flags);
78 iowrite16(reg, priv->reg_base + 0);
79 val = ioread16(priv->reg_base + 2);
80 spin_unlock_irqrestore(&tp->io_lock, flags);
81
82 return val;
83 }
84
sp_technologic_write_reg16(const struct sja1000_priv * priv,int reg,u8 val)85 static void sp_technologic_write_reg16(const struct sja1000_priv *priv,
86 int reg, u8 val)
87 {
88 struct technologic_priv *tp = priv->priv;
89 unsigned long flags;
90
91 spin_lock_irqsave(&tp->io_lock, flags);
92 iowrite16(reg, priv->reg_base + 0);
93 iowrite16(val, priv->reg_base + 2);
94 spin_unlock_irqrestore(&tp->io_lock, flags);
95 }
96
sp_technologic_init(struct sja1000_priv * priv,struct device_node * of)97 static void sp_technologic_init(struct sja1000_priv *priv, struct device_node *of)
98 {
99 struct technologic_priv *tp = priv->priv;
100
101 priv->read_reg = sp_technologic_read_reg16;
102 priv->write_reg = sp_technologic_write_reg16;
103 spin_lock_init(&tp->io_lock);
104 }
105
sp_rzn1_init(struct sja1000_priv * priv,struct device_node * of)106 static void sp_rzn1_init(struct sja1000_priv *priv, struct device_node *of)
107 {
108 priv->flags = SJA1000_QUIRK_NO_CDR_REG | SJA1000_QUIRK_RESET_ON_OVERRUN;
109 }
110
sp_populate(struct sja1000_priv * priv,struct sja1000_platform_data * pdata,unsigned long resource_mem_flags)111 static void sp_populate(struct sja1000_priv *priv,
112 struct sja1000_platform_data *pdata,
113 unsigned long resource_mem_flags)
114 {
115 /* The CAN clock frequency is half the oscillator clock frequency */
116 priv->can.clock.freq = pdata->osc_freq / 2;
117 priv->ocr = pdata->ocr;
118 priv->cdr = pdata->cdr;
119
120 switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
121 case IORESOURCE_MEM_32BIT:
122 priv->read_reg = sp_read_reg32;
123 priv->write_reg = sp_write_reg32;
124 break;
125 case IORESOURCE_MEM_16BIT:
126 priv->read_reg = sp_read_reg16;
127 priv->write_reg = sp_write_reg16;
128 break;
129 case IORESOURCE_MEM_8BIT:
130 default:
131 priv->read_reg = sp_read_reg8;
132 priv->write_reg = sp_write_reg8;
133 break;
134 }
135 }
136
sp_populate_of(struct sja1000_priv * priv,struct device_node * of)137 static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
138 {
139 int err;
140 u32 prop;
141
142 err = of_property_read_u32(of, "reg-io-width", &prop);
143 if (err)
144 prop = 1; /* 8 bit is default */
145
146 switch (prop) {
147 case 4:
148 priv->read_reg = sp_read_reg32;
149 priv->write_reg = sp_write_reg32;
150 break;
151 case 2:
152 priv->read_reg = sp_read_reg16;
153 priv->write_reg = sp_write_reg16;
154 break;
155 case 1:
156 default:
157 priv->read_reg = sp_read_reg8;
158 priv->write_reg = sp_write_reg8;
159 }
160
161 if (!priv->can.clock.freq) {
162 err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
163 if (!err)
164 priv->can.clock.freq = prop / 2;
165 else
166 priv->can.clock.freq = SP_CAN_CLOCK; /* default */
167 }
168
169 err = of_property_read_u32(of, "nxp,tx-output-mode", &prop);
170 if (!err)
171 priv->ocr |= prop & OCR_MODE_MASK;
172 else
173 priv->ocr |= OCR_MODE_NORMAL; /* default */
174
175 err = of_property_read_u32(of, "nxp,tx-output-config", &prop);
176 if (!err)
177 priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
178 else
179 priv->ocr |= OCR_TX0_PULLDOWN; /* default */
180
181 err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop);
182 if (!err && prop) {
183 u32 divider = priv->can.clock.freq * 2 / prop;
184
185 if (divider > 1)
186 priv->cdr |= divider / 2 - 1;
187 else
188 priv->cdr |= CDR_CLKOUT_MASK;
189 } else {
190 priv->cdr |= CDR_CLK_OFF; /* default */
191 }
192
193 if (!of_property_read_bool(of, "nxp,no-comparator-bypass"))
194 priv->cdr |= CDR_CBP; /* default */
195 }
196
197 static struct sja1000_of_data technologic_data = {
198 .priv_sz = sizeof(struct technologic_priv),
199 .init = sp_technologic_init,
200 };
201
202 static struct sja1000_of_data renesas_data = {
203 .init = sp_rzn1_init,
204 };
205
206 static const struct of_device_id sp_of_table[] = {
207 { .compatible = "nxp,sja1000", .data = NULL, },
208 { .compatible = "renesas,rzn1-sja1000", .data = &renesas_data, },
209 { .compatible = "technologic,sja1000", .data = &technologic_data, },
210 { /* sentinel */ },
211 };
212 MODULE_DEVICE_TABLE(of, sp_of_table);
213
sp_probe(struct platform_device * pdev)214 static int sp_probe(struct platform_device *pdev)
215 {
216 int err, irq = 0;
217 void __iomem *addr;
218 struct net_device *dev;
219 struct sja1000_priv *priv;
220 struct resource *res_mem, *res_irq = NULL;
221 struct sja1000_platform_data *pdata;
222 struct device_node *of = pdev->dev.of_node;
223 const struct sja1000_of_data *of_data = NULL;
224 size_t priv_sz = 0;
225 struct clk *clk;
226
227 pdata = dev_get_platdata(&pdev->dev);
228 if (!pdata && !of) {
229 dev_err(&pdev->dev, "No platform data provided!\n");
230 return -ENODEV;
231 }
232
233 res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
234 if (!res_mem)
235 return -ENODEV;
236
237 if (!devm_request_mem_region(&pdev->dev, res_mem->start,
238 resource_size(res_mem), DRV_NAME))
239 return -EBUSY;
240
241 addr = devm_ioremap(&pdev->dev, res_mem->start,
242 resource_size(res_mem));
243 if (!addr)
244 return -ENOMEM;
245
246 if (of) {
247 irq = platform_get_irq(pdev, 0);
248 if (irq < 0)
249 return irq;
250
251 clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
252 if (IS_ERR(clk))
253 return dev_err_probe(&pdev->dev, PTR_ERR(clk),
254 "CAN clk operation failed");
255 } else {
256 res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
257 if (!res_irq)
258 return -ENODEV;
259 }
260
261 of_data = device_get_match_data(&pdev->dev);
262 if (of_data)
263 priv_sz = of_data->priv_sz;
264
265 dev = alloc_sja1000dev(priv_sz);
266 if (!dev)
267 return -ENOMEM;
268 priv = netdev_priv(dev);
269
270 if (res_irq) {
271 irq = res_irq->start;
272 priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
273 if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
274 priv->irq_flags |= IRQF_SHARED;
275 } else {
276 priv->irq_flags = IRQF_SHARED;
277 }
278
279 if (priv->flags & SJA1000_QUIRK_RESET_ON_OVERRUN)
280 priv->irq_flags |= IRQF_ONESHOT;
281
282 dev->irq = irq;
283 priv->reg_base = addr;
284
285 if (of) {
286 if (clk) {
287 priv->can.clock.freq = clk_get_rate(clk) / 2;
288 if (!priv->can.clock.freq) {
289 err = -EINVAL;
290 dev_err(&pdev->dev, "Zero CAN clk rate");
291 goto exit_free;
292 }
293 }
294
295 sp_populate_of(priv, of);
296
297 if (of_data && of_data->init)
298 of_data->init(priv, of);
299 } else {
300 sp_populate(priv, pdata, res_mem->flags);
301 }
302
303 platform_set_drvdata(pdev, dev);
304 SET_NETDEV_DEV(dev, &pdev->dev);
305
306 err = register_sja1000dev(dev);
307 if (err) {
308 dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
309 DRV_NAME, err);
310 goto exit_free;
311 }
312
313 dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
314 DRV_NAME, priv->reg_base, dev->irq);
315 return 0;
316
317 exit_free:
318 free_sja1000dev(dev);
319 return err;
320 }
321
sp_remove(struct platform_device * pdev)322 static void sp_remove(struct platform_device *pdev)
323 {
324 struct net_device *dev = platform_get_drvdata(pdev);
325
326 unregister_sja1000dev(dev);
327 free_sja1000dev(dev);
328 }
329
330 static struct platform_driver sp_driver = {
331 .probe = sp_probe,
332 .remove = sp_remove,
333 .driver = {
334 .name = DRV_NAME,
335 .of_match_table = sp_of_table,
336 },
337 };
338
339 module_platform_driver(sp_driver);
340