1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Driver for Allwinner sunXi IR controller
4 *
5 * Copyright (C) 2014 Alexsey Shestacov <wingrime@linux-sunxi.org>
6 * Copyright (C) 2014 Alexander Bersenev <bay@hackerdom.ru>
7 *
8 * Based on sun5i-ir.c:
9 * Copyright (C) 2007-2012 Daniel Wang
10 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
11 */
12
13 #include <linux/clk.h>
14 #include <linux/interrupt.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/reset.h>
19 #include <media/rc-core.h>
20
21 #define SUNXI_IR_DEV "sunxi-ir"
22
23 /* Registers */
24 /* IR Control */
25 #define SUNXI_IR_CTL_REG 0x00
26 /* Global Enable */
27 #define REG_CTL_GEN BIT(0)
28 /* RX block enable */
29 #define REG_CTL_RXEN BIT(1)
30 /* CIR mode */
31 #define REG_CTL_MD (BIT(4) | BIT(5))
32
33 /* Rx Config */
34 #define SUNXI_IR_RXCTL_REG 0x10
35 /* Pulse Polarity Invert flag */
36 #define REG_RXCTL_RPPI BIT(2)
37
38 /* Rx Data */
39 #define SUNXI_IR_RXFIFO_REG 0x20
40
41 /* Rx Interrupt Enable */
42 #define SUNXI_IR_RXINT_REG 0x2C
43 /* Rx FIFO Overflow Interrupt Enable */
44 #define REG_RXINT_ROI_EN BIT(0)
45 /* Rx Packet End Interrupt Enable */
46 #define REG_RXINT_RPEI_EN BIT(1)
47 /* Rx FIFO Data Available Interrupt Enable */
48 #define REG_RXINT_RAI_EN BIT(4)
49
50 /* Rx FIFO available byte level */
51 #define REG_RXINT_RAL(val) ((val) << 8)
52
53 /* Rx Interrupt Status */
54 #define SUNXI_IR_RXSTA_REG 0x30
55 /* Rx FIFO Overflow */
56 #define REG_RXSTA_ROI REG_RXINT_ROI_EN
57 /* Rx Packet End */
58 #define REG_RXSTA_RPE REG_RXINT_RPEI_EN
59 /* Rx FIFO Data Available */
60 #define REG_RXSTA_RA REG_RXINT_RAI_EN
61 /* RX FIFO Get Available Counter */
62 #define REG_RXSTA_GET_AC(val) (((val) >> 8) & (ir->fifo_size * 2 - 1))
63 /* Clear all interrupt status value */
64 #define REG_RXSTA_CLEARALL 0xff
65
66 /* IR Sample Config */
67 #define SUNXI_IR_CIR_REG 0x34
68 /* CIR_REG register noise threshold */
69 #define REG_CIR_NTHR(val) (((val) << 2) & (GENMASK(7, 2)))
70 /* CIR_REG register idle threshold */
71 #define REG_CIR_ITHR(val) (((val) << 8) & (GENMASK(15, 8)))
72
73 /* Required frequency for IR0 or IR1 clock in CIR mode (default) */
74 #define SUNXI_IR_BASE_CLK 8000000
75 /* Noise threshold in samples */
76 #define SUNXI_IR_RXNOISE 1
77
78 /**
79 * struct sunxi_ir_quirks - Differences between SoC variants.
80 *
81 * @has_reset: SoC needs reset deasserted.
82 * @fifo_size: size of the fifo.
83 */
84 struct sunxi_ir_quirks {
85 bool has_reset;
86 int fifo_size;
87 };
88
89 struct sunxi_ir {
90 struct rc_dev *rc;
91 void __iomem *base;
92 int irq;
93 int fifo_size;
94 struct clk *clk;
95 struct clk *apb_clk;
96 struct reset_control *rst;
97 const char *map_name;
98 };
99
sunxi_ir_irq(int irqno,void * dev_id)100 static irqreturn_t sunxi_ir_irq(int irqno, void *dev_id)
101 {
102 unsigned long status;
103 unsigned char dt;
104 unsigned int cnt, rc;
105 struct sunxi_ir *ir = dev_id;
106 struct ir_raw_event rawir = {};
107
108 status = readl(ir->base + SUNXI_IR_RXSTA_REG);
109
110 /* clean all pending statuses */
111 writel(status | REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
112
113 if (status & (REG_RXSTA_RA | REG_RXSTA_RPE)) {
114 /* How many messages in fifo */
115 rc = REG_RXSTA_GET_AC(status);
116 /* Sanity check */
117 rc = rc > ir->fifo_size ? ir->fifo_size : rc;
118 /* If we have data */
119 for (cnt = 0; cnt < rc; cnt++) {
120 /* for each bit in fifo */
121 dt = readb(ir->base + SUNXI_IR_RXFIFO_REG);
122 rawir.pulse = (dt & 0x80) != 0;
123 rawir.duration = ((dt & 0x7f) + 1) *
124 ir->rc->rx_resolution;
125 ir_raw_event_store_with_filter(ir->rc, &rawir);
126 }
127 }
128
129 if (status & REG_RXSTA_ROI) {
130 ir_raw_event_overflow(ir->rc);
131 } else if (status & REG_RXSTA_RPE) {
132 ir_raw_event_set_idle(ir->rc, true);
133 ir_raw_event_handle(ir->rc);
134 } else {
135 ir_raw_event_handle(ir->rc);
136 }
137
138 return IRQ_HANDLED;
139 }
140
141 /* Convert idle threshold to usec */
sunxi_ithr_to_usec(unsigned int base_clk,unsigned int ithr)142 static unsigned int sunxi_ithr_to_usec(unsigned int base_clk, unsigned int ithr)
143 {
144 return DIV_ROUND_CLOSEST(USEC_PER_SEC * (ithr + 1),
145 base_clk / (128 * 64));
146 }
147
148 /* Convert usec to idle threshold */
sunxi_usec_to_ithr(unsigned int base_clk,unsigned int usec)149 static unsigned int sunxi_usec_to_ithr(unsigned int base_clk, unsigned int usec)
150 {
151 /* make sure we don't end up with a timeout less than requested */
152 return DIV_ROUND_UP((base_clk / (128 * 64)) * usec, USEC_PER_SEC) - 1;
153 }
154
sunxi_ir_set_timeout(struct rc_dev * rc_dev,unsigned int timeout)155 static int sunxi_ir_set_timeout(struct rc_dev *rc_dev, unsigned int timeout)
156 {
157 struct sunxi_ir *ir = rc_dev->priv;
158 unsigned int base_clk = clk_get_rate(ir->clk);
159
160 unsigned int ithr = sunxi_usec_to_ithr(base_clk, timeout);
161
162 dev_dbg(rc_dev->dev.parent, "setting idle threshold to %u\n", ithr);
163
164 /* Set noise threshold and idle threshold */
165 writel(REG_CIR_NTHR(SUNXI_IR_RXNOISE) | REG_CIR_ITHR(ithr),
166 ir->base + SUNXI_IR_CIR_REG);
167
168 rc_dev->timeout = sunxi_ithr_to_usec(base_clk, ithr);
169
170 return 0;
171 }
172
sunxi_ir_hw_init(struct device * dev)173 static int sunxi_ir_hw_init(struct device *dev)
174 {
175 struct sunxi_ir *ir = dev_get_drvdata(dev);
176 u32 tmp;
177 int ret;
178
179 ret = reset_control_deassert(ir->rst);
180 if (ret)
181 return ret;
182
183 ret = clk_prepare_enable(ir->apb_clk);
184 if (ret) {
185 dev_err(dev, "failed to enable apb clk\n");
186 goto exit_assert_reset;
187 }
188
189 ret = clk_prepare_enable(ir->clk);
190 if (ret) {
191 dev_err(dev, "failed to enable ir clk\n");
192 goto exit_disable_apb_clk;
193 }
194
195 /* Enable CIR Mode */
196 writel(REG_CTL_MD, ir->base + SUNXI_IR_CTL_REG);
197
198 /* Set noise threshold and idle threshold */
199 sunxi_ir_set_timeout(ir->rc, ir->rc->timeout);
200
201 /* Invert Input Signal */
202 writel(REG_RXCTL_RPPI, ir->base + SUNXI_IR_RXCTL_REG);
203
204 /* Clear All Rx Interrupt Status */
205 writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
206
207 /*
208 * Enable IRQ on overflow, packet end, FIFO available with trigger
209 * level
210 */
211 writel(REG_RXINT_ROI_EN | REG_RXINT_RPEI_EN |
212 REG_RXINT_RAI_EN | REG_RXINT_RAL(ir->fifo_size / 2 - 1),
213 ir->base + SUNXI_IR_RXINT_REG);
214
215 /* Enable IR Module */
216 tmp = readl(ir->base + SUNXI_IR_CTL_REG);
217 writel(tmp | REG_CTL_GEN | REG_CTL_RXEN, ir->base + SUNXI_IR_CTL_REG);
218
219 return 0;
220
221 exit_disable_apb_clk:
222 clk_disable_unprepare(ir->apb_clk);
223 exit_assert_reset:
224 reset_control_assert(ir->rst);
225
226 return ret;
227 }
228
sunxi_ir_hw_exit(struct device * dev)229 static void sunxi_ir_hw_exit(struct device *dev)
230 {
231 struct sunxi_ir *ir = dev_get_drvdata(dev);
232
233 clk_disable_unprepare(ir->clk);
234 clk_disable_unprepare(ir->apb_clk);
235 reset_control_assert(ir->rst);
236 }
237
sunxi_ir_suspend(struct device * dev)238 static int __maybe_unused sunxi_ir_suspend(struct device *dev)
239 {
240 sunxi_ir_hw_exit(dev);
241
242 return 0;
243 }
244
sunxi_ir_resume(struct device * dev)245 static int __maybe_unused sunxi_ir_resume(struct device *dev)
246 {
247 return sunxi_ir_hw_init(dev);
248 }
249
250 static SIMPLE_DEV_PM_OPS(sunxi_ir_pm_ops, sunxi_ir_suspend, sunxi_ir_resume);
251
sunxi_ir_probe(struct platform_device * pdev)252 static int sunxi_ir_probe(struct platform_device *pdev)
253 {
254 int ret = 0;
255
256 struct device *dev = &pdev->dev;
257 struct device_node *dn = dev->of_node;
258 const struct sunxi_ir_quirks *quirks;
259 struct sunxi_ir *ir;
260 u32 b_clk_freq = SUNXI_IR_BASE_CLK;
261
262 ir = devm_kzalloc(dev, sizeof(struct sunxi_ir), GFP_KERNEL);
263 if (!ir)
264 return -ENOMEM;
265
266 quirks = of_device_get_match_data(&pdev->dev);
267 if (!quirks) {
268 dev_err(&pdev->dev, "Failed to determine the quirks to use\n");
269 return -ENODEV;
270 }
271
272 ir->fifo_size = quirks->fifo_size;
273
274 /* Clock */
275 ir->apb_clk = devm_clk_get(dev, "apb");
276 if (IS_ERR(ir->apb_clk)) {
277 dev_err(dev, "failed to get a apb clock.\n");
278 return PTR_ERR(ir->apb_clk);
279 }
280 ir->clk = devm_clk_get(dev, "ir");
281 if (IS_ERR(ir->clk)) {
282 dev_err(dev, "failed to get a ir clock.\n");
283 return PTR_ERR(ir->clk);
284 }
285
286 /* Base clock frequency (optional) */
287 of_property_read_u32(dn, "clock-frequency", &b_clk_freq);
288
289 /* Reset */
290 if (quirks->has_reset) {
291 ir->rst = devm_reset_control_get_exclusive(dev, NULL);
292 if (IS_ERR(ir->rst))
293 return PTR_ERR(ir->rst);
294 }
295
296 ret = clk_set_rate(ir->clk, b_clk_freq);
297 if (ret) {
298 dev_err(dev, "set ir base clock failed!\n");
299 return ret;
300 }
301 dev_dbg(dev, "set base clock frequency to %d Hz.\n", b_clk_freq);
302
303 /* IO */
304 ir->base = devm_platform_ioremap_resource(pdev, 0);
305 if (IS_ERR(ir->base)) {
306 return PTR_ERR(ir->base);
307 }
308
309 ir->rc = rc_allocate_device(RC_DRIVER_IR_RAW);
310 if (!ir->rc) {
311 dev_err(dev, "failed to allocate device\n");
312 return -ENOMEM;
313 }
314
315 ir->rc->priv = ir;
316 ir->rc->device_name = SUNXI_IR_DEV;
317 ir->rc->input_phys = "sunxi-ir/input0";
318 ir->rc->input_id.bustype = BUS_HOST;
319 ir->rc->input_id.vendor = 0x0001;
320 ir->rc->input_id.product = 0x0001;
321 ir->rc->input_id.version = 0x0100;
322 ir->map_name = of_get_property(dn, "linux,rc-map-name", NULL);
323 ir->rc->map_name = ir->map_name ?: RC_MAP_EMPTY;
324 ir->rc->dev.parent = dev;
325 ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
326 /* Frequency after IR internal divider with sample period in us */
327 ir->rc->rx_resolution = (USEC_PER_SEC / (b_clk_freq / 64));
328 ir->rc->timeout = IR_DEFAULT_TIMEOUT;
329 ir->rc->min_timeout = sunxi_ithr_to_usec(b_clk_freq, 0);
330 ir->rc->max_timeout = sunxi_ithr_to_usec(b_clk_freq, 255);
331 ir->rc->s_timeout = sunxi_ir_set_timeout;
332 ir->rc->driver_name = SUNXI_IR_DEV;
333
334 ret = rc_register_device(ir->rc);
335 if (ret) {
336 dev_err(dev, "failed to register rc device\n");
337 goto exit_free_dev;
338 }
339
340 platform_set_drvdata(pdev, ir);
341
342 /* IRQ */
343 ir->irq = platform_get_irq(pdev, 0);
344 if (ir->irq < 0) {
345 ret = ir->irq;
346 goto exit_free_dev;
347 }
348
349 ret = devm_request_irq(dev, ir->irq, sunxi_ir_irq, 0, SUNXI_IR_DEV, ir);
350 if (ret) {
351 dev_err(dev, "failed request irq\n");
352 goto exit_free_dev;
353 }
354
355 ret = sunxi_ir_hw_init(dev);
356 if (ret)
357 goto exit_free_dev;
358
359 dev_info(dev, "initialized sunXi IR driver\n");
360 return 0;
361
362 exit_free_dev:
363 rc_free_device(ir->rc);
364
365 return ret;
366 }
367
sunxi_ir_remove(struct platform_device * pdev)368 static void sunxi_ir_remove(struct platform_device *pdev)
369 {
370 struct sunxi_ir *ir = platform_get_drvdata(pdev);
371
372 rc_unregister_device(ir->rc);
373 sunxi_ir_hw_exit(&pdev->dev);
374 }
375
sunxi_ir_shutdown(struct platform_device * pdev)376 static void sunxi_ir_shutdown(struct platform_device *pdev)
377 {
378 sunxi_ir_hw_exit(&pdev->dev);
379 }
380
381 static const struct sunxi_ir_quirks sun4i_a10_ir_quirks = {
382 .has_reset = false,
383 .fifo_size = 16,
384 };
385
386 static const struct sunxi_ir_quirks sun5i_a13_ir_quirks = {
387 .has_reset = false,
388 .fifo_size = 64,
389 };
390
391 static const struct sunxi_ir_quirks sun6i_a31_ir_quirks = {
392 .has_reset = true,
393 .fifo_size = 64,
394 };
395
396 static const struct of_device_id sunxi_ir_match[] = {
397 {
398 .compatible = "allwinner,sun4i-a10-ir",
399 .data = &sun4i_a10_ir_quirks,
400 },
401 {
402 .compatible = "allwinner,sun5i-a13-ir",
403 .data = &sun5i_a13_ir_quirks,
404 },
405 {
406 .compatible = "allwinner,sun6i-a31-ir",
407 .data = &sun6i_a31_ir_quirks,
408 },
409 {}
410 };
411 MODULE_DEVICE_TABLE(of, sunxi_ir_match);
412
413 static struct platform_driver sunxi_ir_driver = {
414 .probe = sunxi_ir_probe,
415 .remove_new = sunxi_ir_remove,
416 .shutdown = sunxi_ir_shutdown,
417 .driver = {
418 .name = SUNXI_IR_DEV,
419 .of_match_table = sunxi_ir_match,
420 .pm = &sunxi_ir_pm_ops,
421 },
422 };
423
424 module_platform_driver(sunxi_ir_driver);
425
426 MODULE_DESCRIPTION("Allwinner sunXi IR controller driver");
427 MODULE_AUTHOR("Alexsey Shestacov <wingrime@linux-sunxi.org>");
428 MODULE_LICENSE("GPL");
429