xref: /linux/drivers/media/rc/sunxi-cir.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * Driver for Allwinner sunXi IR controller
3  *
4  * Copyright (C) 2014 Alexsey Shestacov <wingrime@linux-sunxi.org>
5  * Copyright (C) 2014 Alexander Bersenev <bay@hackerdom.ru>
6  *
7  * Based on sun5i-ir.c:
8  * Copyright (C) 2007-2012 Daniel Wang
9  * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  */
21 
22 #include <linux/clk.h>
23 #include <linux/interrupt.h>
24 #include <linux/module.h>
25 #include <linux/of_platform.h>
26 #include <media/rc-core.h>
27 
28 #define SUNXI_IR_DEV "sunxi-ir"
29 
30 /* Registers */
31 /* IR Control */
32 #define SUNXI_IR_CTL_REG      0x00
33 /* Global Enable */
34 #define REG_CTL_GEN			BIT(0)
35 /* RX block enable */
36 #define REG_CTL_RXEN			BIT(1)
37 /* CIR mode */
38 #define REG_CTL_MD			(BIT(4) | BIT(5))
39 
40 /* Rx Config */
41 #define SUNXI_IR_RXCTL_REG    0x10
42 /* Pulse Polarity Invert flag */
43 #define REG_RXCTL_RPPI			BIT(2)
44 
45 /* Rx Data */
46 #define SUNXI_IR_RXFIFO_REG   0x20
47 
48 /* Rx Interrupt Enable */
49 #define SUNXI_IR_RXINT_REG    0x2C
50 /* Rx FIFO Overflow */
51 #define REG_RXINT_ROI_EN		BIT(0)
52 /* Rx Packet End */
53 #define REG_RXINT_RPEI_EN		BIT(1)
54 /* Rx FIFO Data Available */
55 #define REG_RXINT_RAI_EN		BIT(4)
56 
57 /* Rx FIFO available byte level */
58 #define REG_RXINT_RAL(val)    (((val) << 8) & (GENMASK(11, 8)))
59 
60 /* Rx Interrupt Status */
61 #define SUNXI_IR_RXSTA_REG    0x30
62 /* RX FIFO Get Available Counter */
63 #define REG_RXSTA_GET_AC(val) (((val) >> 8) & (GENMASK(5, 0)))
64 /* Clear all interrupt status value */
65 #define REG_RXSTA_CLEARALL    0xff
66 
67 /* IR Sample Config */
68 #define SUNXI_IR_CIR_REG      0x34
69 /* CIR_REG register noise threshold */
70 #define REG_CIR_NTHR(val)    (((val) << 2) & (GENMASK(7, 2)))
71 /* CIR_REG register idle threshold */
72 #define REG_CIR_ITHR(val)    (((val) << 8) & (GENMASK(15, 8)))
73 
74 /* Hardware supported fifo size */
75 #define SUNXI_IR_FIFO_SIZE    16
76 /* How many messages in FIFO trigger IRQ */
77 #define TRIGGER_LEVEL         8
78 /* Required frequency for IR0 or IR1 clock in CIR mode */
79 #define SUNXI_IR_BASE_CLK     8000000
80 /* Frequency after IR internal divider  */
81 #define SUNXI_IR_CLK          (SUNXI_IR_BASE_CLK / 64)
82 /* Sample period in ns */
83 #define SUNXI_IR_SAMPLE       (1000000000ul / SUNXI_IR_CLK)
84 /* Noise threshold in samples  */
85 #define SUNXI_IR_RXNOISE      1
86 /* Idle Threshold in samples */
87 #define SUNXI_IR_RXIDLE       20
88 /* Time after which device stops sending data in ms */
89 #define SUNXI_IR_TIMEOUT      120
90 
91 struct sunxi_ir {
92 	spinlock_t      ir_lock;
93 	struct rc_dev   *rc;
94 	void __iomem    *base;
95 	int             irq;
96 	struct clk      *clk;
97 	struct clk      *apb_clk;
98 	const char      *map_name;
99 };
100 
101 static irqreturn_t sunxi_ir_irq(int irqno, void *dev_id)
102 {
103 	unsigned long status;
104 	unsigned char dt;
105 	unsigned int cnt, rc;
106 	struct sunxi_ir *ir = dev_id;
107 	DEFINE_IR_RAW_EVENT(rawir);
108 
109 	spin_lock(&ir->ir_lock);
110 
111 	status = readl(ir->base + SUNXI_IR_RXSTA_REG);
112 
113 	/* clean all pending statuses */
114 	writel(status | REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
115 
116 	if (status & REG_RXINT_RAI_EN) {
117 		/* How many messages in fifo */
118 		rc  = REG_RXSTA_GET_AC(status);
119 		/* Sanity check */
120 		rc = rc > SUNXI_IR_FIFO_SIZE ? SUNXI_IR_FIFO_SIZE : rc;
121 		/* If we have data */
122 		for (cnt = 0; cnt < rc; cnt++) {
123 			/* for each bit in fifo */
124 			dt = readb(ir->base + SUNXI_IR_RXFIFO_REG);
125 			rawir.pulse = (dt & 0x80) != 0;
126 			rawir.duration = ((dt & 0x7f) + 1) * SUNXI_IR_SAMPLE;
127 			ir_raw_event_store_with_filter(ir->rc, &rawir);
128 		}
129 	}
130 
131 	if (status & REG_RXINT_ROI_EN) {
132 		ir_raw_event_reset(ir->rc);
133 	} else if (status & REG_RXINT_RPEI_EN) {
134 		ir_raw_event_set_idle(ir->rc, true);
135 		ir_raw_event_handle(ir->rc);
136 	}
137 
138 	spin_unlock(&ir->ir_lock);
139 
140 	return IRQ_HANDLED;
141 }
142 
143 static int sunxi_ir_probe(struct platform_device *pdev)
144 {
145 	int ret = 0;
146 	unsigned long tmp = 0;
147 
148 	struct device *dev = &pdev->dev;
149 	struct device_node *dn = dev->of_node;
150 	struct resource *res;
151 	struct sunxi_ir *ir;
152 
153 	ir = devm_kzalloc(dev, sizeof(struct sunxi_ir), GFP_KERNEL);
154 	if (!ir)
155 		return -ENOMEM;
156 
157 	/* Clock */
158 	ir->apb_clk = devm_clk_get(dev, "apb");
159 	if (IS_ERR(ir->apb_clk)) {
160 		dev_err(dev, "failed to get a apb clock.\n");
161 		return PTR_ERR(ir->apb_clk);
162 	}
163 	ir->clk = devm_clk_get(dev, "ir");
164 	if (IS_ERR(ir->clk)) {
165 		dev_err(dev, "failed to get a ir clock.\n");
166 		return PTR_ERR(ir->clk);
167 	}
168 
169 	ret = clk_set_rate(ir->clk, SUNXI_IR_BASE_CLK);
170 	if (ret) {
171 		dev_err(dev, "set ir base clock failed!\n");
172 		return ret;
173 	}
174 
175 	if (clk_prepare_enable(ir->apb_clk)) {
176 		dev_err(dev, "try to enable apb_ir_clk failed\n");
177 		return -EINVAL;
178 	}
179 
180 	if (clk_prepare_enable(ir->clk)) {
181 		dev_err(dev, "try to enable ir_clk failed\n");
182 		ret = -EINVAL;
183 		goto exit_clkdisable_apb_clk;
184 	}
185 
186 	/* IO */
187 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
188 	ir->base = devm_ioremap_resource(dev, res);
189 	if (IS_ERR(ir->base)) {
190 		dev_err(dev, "failed to map registers\n");
191 		ret = PTR_ERR(ir->base);
192 		goto exit_clkdisable_clk;
193 	}
194 
195 	ir->rc = rc_allocate_device();
196 	if (!ir->rc) {
197 		dev_err(dev, "failed to allocate device\n");
198 		ret = -ENOMEM;
199 		goto exit_clkdisable_clk;
200 	}
201 
202 	ir->rc->priv = ir;
203 	ir->rc->input_name = SUNXI_IR_DEV;
204 	ir->rc->input_phys = "sunxi-ir/input0";
205 	ir->rc->input_id.bustype = BUS_HOST;
206 	ir->rc->input_id.vendor = 0x0001;
207 	ir->rc->input_id.product = 0x0001;
208 	ir->rc->input_id.version = 0x0100;
209 	ir->map_name = of_get_property(dn, "linux,rc-map-name", NULL);
210 	ir->rc->map_name = ir->map_name ?: RC_MAP_EMPTY;
211 	ir->rc->dev.parent = dev;
212 	ir->rc->driver_type = RC_DRIVER_IR_RAW;
213 	ir->rc->allowed_protocols = RC_BIT_ALL;
214 	ir->rc->rx_resolution = SUNXI_IR_SAMPLE;
215 	ir->rc->timeout = MS_TO_NS(SUNXI_IR_TIMEOUT);
216 	ir->rc->driver_name = SUNXI_IR_DEV;
217 
218 	ret = rc_register_device(ir->rc);
219 	if (ret) {
220 		dev_err(dev, "failed to register rc device\n");
221 		goto exit_free_dev;
222 	}
223 
224 	platform_set_drvdata(pdev, ir);
225 
226 	/* IRQ */
227 	ir->irq = platform_get_irq(pdev, 0);
228 	if (ir->irq < 0) {
229 		dev_err(dev, "no irq resource\n");
230 		ret = ir->irq;
231 		goto exit_free_dev;
232 	}
233 
234 	ret = devm_request_irq(dev, ir->irq, sunxi_ir_irq, 0, SUNXI_IR_DEV, ir);
235 	if (ret) {
236 		dev_err(dev, "failed request irq\n");
237 		goto exit_free_dev;
238 	}
239 
240 	/* Enable CIR Mode */
241 	writel(REG_CTL_MD, ir->base+SUNXI_IR_CTL_REG);
242 
243 	/* Set noise threshold and idle threshold */
244 	writel(REG_CIR_NTHR(SUNXI_IR_RXNOISE)|REG_CIR_ITHR(SUNXI_IR_RXIDLE),
245 	       ir->base + SUNXI_IR_CIR_REG);
246 
247 	/* Invert Input Signal */
248 	writel(REG_RXCTL_RPPI, ir->base + SUNXI_IR_RXCTL_REG);
249 
250 	/* Clear All Rx Interrupt Status */
251 	writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
252 
253 	/*
254 	 * Enable IRQ on overflow, packet end, FIFO available with trigger
255 	 * level
256 	 */
257 	writel(REG_RXINT_ROI_EN | REG_RXINT_RPEI_EN |
258 	       REG_RXINT_RAI_EN | REG_RXINT_RAL(TRIGGER_LEVEL - 1),
259 	       ir->base + SUNXI_IR_RXINT_REG);
260 
261 	/* Enable IR Module */
262 	tmp = readl(ir->base + SUNXI_IR_CTL_REG);
263 	writel(tmp | REG_CTL_GEN | REG_CTL_RXEN, ir->base + SUNXI_IR_CTL_REG);
264 
265 	dev_info(dev, "initialized sunXi IR driver\n");
266 	return 0;
267 
268 exit_free_dev:
269 	rc_free_device(ir->rc);
270 exit_clkdisable_clk:
271 	clk_disable_unprepare(ir->clk);
272 exit_clkdisable_apb_clk:
273 	clk_disable_unprepare(ir->apb_clk);
274 
275 	return ret;
276 }
277 
278 static int sunxi_ir_remove(struct platform_device *pdev)
279 {
280 	unsigned long flags;
281 	struct sunxi_ir *ir = platform_get_drvdata(pdev);
282 
283 	clk_disable_unprepare(ir->clk);
284 	clk_disable_unprepare(ir->apb_clk);
285 
286 	spin_lock_irqsave(&ir->ir_lock, flags);
287 	/* disable IR IRQ */
288 	writel(0, ir->base + SUNXI_IR_RXINT_REG);
289 	/* clear All Rx Interrupt Status */
290 	writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
291 	/* disable IR */
292 	writel(0, ir->base + SUNXI_IR_CTL_REG);
293 	spin_unlock_irqrestore(&ir->ir_lock, flags);
294 
295 	rc_unregister_device(ir->rc);
296 	return 0;
297 }
298 
299 static const struct of_device_id sunxi_ir_match[] = {
300 	{ .compatible = "allwinner,sun4i-a10-ir", },
301 	{},
302 };
303 
304 static struct platform_driver sunxi_ir_driver = {
305 	.probe          = sunxi_ir_probe,
306 	.remove         = sunxi_ir_remove,
307 	.driver = {
308 		.name = SUNXI_IR_DEV,
309 		.of_match_table = sunxi_ir_match,
310 	},
311 };
312 
313 module_platform_driver(sunxi_ir_driver);
314 
315 MODULE_DESCRIPTION("Allwinner sunXi IR controller driver");
316 MODULE_AUTHOR("Alexsey Shestacov <wingrime@linux-sunxi.org>");
317 MODULE_LICENSE("GPL");
318