1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Microchip Image Sensor Controller (ISC) driver
4  *
5  * Copyright (C) 2016-2019 Microchip Technology, Inc.
6  *
7  * Author: Songjun Wu
8  * Author: Eugen Hristev <eugen.hristev@microchip.com>
9  *
10  *
11  * Sensor-->PFE-->WB-->CFA-->CC-->GAM-->CSC-->CBC-->SUB-->RLP-->DMA
12  *
13  * ISC video pipeline integrates the following submodules:
14  * PFE: Parallel Front End to sample the camera sensor input stream
15  *  WB: Programmable white balance in the Bayer domain
16  * CFA: Color filter array interpolation module
17  *  CC: Programmable color correction
18  * GAM: Gamma correction
19  * CSC: Programmable color space conversion
20  * CBC: Contrast and Brightness control
21  * SUB: This module performs YCbCr444 to YCbCr420 chrominance subsampling
22  * RLP: This module performs rounding, range limiting
23  *      and packing of the incoming data
24  */
25 
26 #include <linux/clk.h>
27 #include <linux/clkdev.h>
28 #include <linux/clk-provider.h>
29 #include <linux/delay.h>
30 #include <linux/interrupt.h>
31 #include <linux/math64.h>
32 #include <linux/module.h>
33 #include <linux/of.h>
34 #include <linux/of_graph.h>
35 #include <linux/platform_device.h>
36 #include <linux/pm_runtime.h>
37 #include <linux/regmap.h>
38 #include <linux/videodev2.h>
39 
40 #include <media/v4l2-ctrls.h>
41 #include <media/v4l2-device.h>
42 #include <media/v4l2-event.h>
43 #include <media/v4l2-image-sizes.h>
44 #include <media/v4l2-ioctl.h>
45 #include <media/v4l2-fwnode.h>
46 #include <media/v4l2-subdev.h>
47 #include <media/videobuf2-dma-contig.h>
48 
49 #include "atmel-isc-regs.h"
50 #include "atmel-isc.h"
51 
52 #define ISC_MAX_SUPPORT_WIDTH   2592
53 #define ISC_MAX_SUPPORT_HEIGHT  1944
54 
55 #define ISC_CLK_MAX_DIV		255
56 
isc_parse_dt(struct device * dev,struct isc_device * isc)57 static int isc_parse_dt(struct device *dev, struct isc_device *isc)
58 {
59 	struct device_node *np = dev->of_node;
60 	struct device_node *epn = NULL;
61 	struct isc_subdev_entity *subdev_entity;
62 	unsigned int flags;
63 	int ret;
64 
65 	INIT_LIST_HEAD(&isc->subdev_entities);
66 
67 	while (1) {
68 		struct v4l2_fwnode_endpoint v4l2_epn = { .bus_type = 0 };
69 
70 		epn = of_graph_get_next_endpoint(np, epn);
71 		if (!epn)
72 			return 0;
73 
74 		ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(epn),
75 						 &v4l2_epn);
76 		if (ret) {
77 			ret = -EINVAL;
78 			dev_err(dev, "Could not parse the endpoint\n");
79 			break;
80 		}
81 
82 		subdev_entity = devm_kzalloc(dev, sizeof(*subdev_entity),
83 					     GFP_KERNEL);
84 		if (!subdev_entity) {
85 			ret = -ENOMEM;
86 			break;
87 		}
88 		subdev_entity->epn = epn;
89 
90 		flags = v4l2_epn.bus.parallel.flags;
91 
92 		if (flags & V4L2_MBUS_HSYNC_ACTIVE_LOW)
93 			subdev_entity->pfe_cfg0 = ISC_PFE_CFG0_HPOL_LOW;
94 
95 		if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
96 			subdev_entity->pfe_cfg0 |= ISC_PFE_CFG0_VPOL_LOW;
97 
98 		if (flags & V4L2_MBUS_PCLK_SAMPLE_FALLING)
99 			subdev_entity->pfe_cfg0 |= ISC_PFE_CFG0_PPOL_LOW;
100 
101 		if (v4l2_epn.bus_type == V4L2_MBUS_BT656)
102 			subdev_entity->pfe_cfg0 |= ISC_PFE_CFG0_CCIR_CRC |
103 					ISC_PFE_CFG0_CCIR656;
104 
105 		list_add_tail(&subdev_entity->list, &isc->subdev_entities);
106 	}
107 	of_node_put(epn);
108 
109 	return ret;
110 }
111 
atmel_isc_probe(struct platform_device * pdev)112 static int atmel_isc_probe(struct platform_device *pdev)
113 {
114 	struct device *dev = &pdev->dev;
115 	struct isc_device *isc;
116 	struct resource *res;
117 	void __iomem *io_base;
118 	struct isc_subdev_entity *subdev_entity;
119 	int irq;
120 	int ret;
121 
122 	isc = devm_kzalloc(dev, sizeof(*isc), GFP_KERNEL);
123 	if (!isc)
124 		return -ENOMEM;
125 
126 	platform_set_drvdata(pdev, isc);
127 	isc->dev = dev;
128 
129 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
130 	io_base = devm_ioremap_resource(dev, res);
131 	if (IS_ERR(io_base))
132 		return PTR_ERR(io_base);
133 
134 	isc->regmap = devm_regmap_init_mmio(dev, io_base, &isc_regmap_config);
135 	if (IS_ERR(isc->regmap)) {
136 		ret = PTR_ERR(isc->regmap);
137 		dev_err(dev, "failed to init register map: %d\n", ret);
138 		return ret;
139 	}
140 
141 	irq = platform_get_irq(pdev, 0);
142 	if (irq < 0)
143 		return irq;
144 
145 	ret = devm_request_irq(dev, irq, isc_interrupt, 0,
146 			       ATMEL_ISC_NAME, isc);
147 	if (ret < 0) {
148 		dev_err(dev, "can't register ISR for IRQ %u (ret=%i)\n",
149 			irq, ret);
150 		return ret;
151 	}
152 
153 	ret = isc_pipeline_init(isc);
154 	if (ret)
155 		return ret;
156 
157 	isc->hclock = devm_clk_get(dev, "hclock");
158 	if (IS_ERR(isc->hclock)) {
159 		ret = PTR_ERR(isc->hclock);
160 		dev_err(dev, "failed to get hclock: %d\n", ret);
161 		return ret;
162 	}
163 
164 	ret = clk_prepare_enable(isc->hclock);
165 	if (ret) {
166 		dev_err(dev, "failed to enable hclock: %d\n", ret);
167 		return ret;
168 	}
169 
170 	ret = isc_clk_init(isc);
171 	if (ret) {
172 		dev_err(dev, "failed to init isc clock: %d\n", ret);
173 		goto unprepare_hclk;
174 	}
175 
176 	isc->ispck = isc->isc_clks[ISC_ISPCK].clk;
177 
178 	ret = clk_prepare_enable(isc->ispck);
179 	if (ret) {
180 		dev_err(dev, "failed to enable ispck: %d\n", ret);
181 		goto unprepare_hclk;
182 	}
183 
184 	/* ispck should be greater or equal to hclock */
185 	ret = clk_set_rate(isc->ispck, clk_get_rate(isc->hclock));
186 	if (ret) {
187 		dev_err(dev, "failed to set ispck rate: %d\n", ret);
188 		goto unprepare_clk;
189 	}
190 
191 	ret = v4l2_device_register(dev, &isc->v4l2_dev);
192 	if (ret) {
193 		dev_err(dev, "unable to register v4l2 device.\n");
194 		goto unprepare_clk;
195 	}
196 
197 	ret = isc_parse_dt(dev, isc);
198 	if (ret) {
199 		dev_err(dev, "fail to parse device tree\n");
200 		goto unregister_v4l2_device;
201 	}
202 
203 	if (list_empty(&isc->subdev_entities)) {
204 		dev_err(dev, "no subdev found\n");
205 		ret = -ENODEV;
206 		goto unregister_v4l2_device;
207 	}
208 
209 	list_for_each_entry(subdev_entity, &isc->subdev_entities, list) {
210 		struct v4l2_async_subdev *asd;
211 
212 		v4l2_async_notifier_init(&subdev_entity->notifier);
213 
214 		asd = v4l2_async_notifier_add_fwnode_remote_subdev(
215 					&subdev_entity->notifier,
216 					of_fwnode_handle(subdev_entity->epn),
217 					struct v4l2_async_subdev);
218 
219 		of_node_put(subdev_entity->epn);
220 		subdev_entity->epn = NULL;
221 
222 		if (IS_ERR(asd)) {
223 			ret = PTR_ERR(asd);
224 			goto cleanup_subdev;
225 		}
226 
227 		subdev_entity->notifier.ops = &isc_async_ops;
228 
229 		ret = v4l2_async_notifier_register(&isc->v4l2_dev,
230 						   &subdev_entity->notifier);
231 		if (ret) {
232 			dev_err(dev, "fail to register async notifier\n");
233 			goto cleanup_subdev;
234 		}
235 
236 		if (video_is_registered(&isc->video_dev))
237 			break;
238 	}
239 
240 	pm_runtime_set_active(dev);
241 	pm_runtime_enable(dev);
242 	pm_request_idle(dev);
243 
244 	return 0;
245 
246 cleanup_subdev:
247 	isc_subdev_cleanup(isc);
248 
249 unregister_v4l2_device:
250 	v4l2_device_unregister(&isc->v4l2_dev);
251 
252 unprepare_clk:
253 	clk_disable_unprepare(isc->ispck);
254 unprepare_hclk:
255 	clk_disable_unprepare(isc->hclock);
256 
257 	isc_clk_cleanup(isc);
258 
259 	return ret;
260 }
261 
atmel_isc_remove(struct platform_device * pdev)262 static int atmel_isc_remove(struct platform_device *pdev)
263 {
264 	struct isc_device *isc = platform_get_drvdata(pdev);
265 
266 	pm_runtime_disable(&pdev->dev);
267 
268 	isc_subdev_cleanup(isc);
269 
270 	v4l2_device_unregister(&isc->v4l2_dev);
271 
272 	clk_disable_unprepare(isc->ispck);
273 	clk_disable_unprepare(isc->hclock);
274 
275 	isc_clk_cleanup(isc);
276 
277 	return 0;
278 }
279 
isc_runtime_suspend(struct device * dev)280 static int __maybe_unused isc_runtime_suspend(struct device *dev)
281 {
282 	struct isc_device *isc = dev_get_drvdata(dev);
283 
284 	clk_disable_unprepare(isc->ispck);
285 	clk_disable_unprepare(isc->hclock);
286 
287 	return 0;
288 }
289 
isc_runtime_resume(struct device * dev)290 static int __maybe_unused isc_runtime_resume(struct device *dev)
291 {
292 	struct isc_device *isc = dev_get_drvdata(dev);
293 	int ret;
294 
295 	ret = clk_prepare_enable(isc->hclock);
296 	if (ret)
297 		return ret;
298 
299 	ret = clk_prepare_enable(isc->ispck);
300 	if (ret)
301 		clk_disable_unprepare(isc->hclock);
302 
303 	return ret;
304 }
305 
306 static const struct dev_pm_ops atmel_isc_dev_pm_ops = {
307 	SET_RUNTIME_PM_OPS(isc_runtime_suspend, isc_runtime_resume, NULL)
308 };
309 
310 #if IS_ENABLED(CONFIG_OF)
311 static const struct of_device_id atmel_isc_of_match[] = {
312 	{ .compatible = "atmel,sama5d2-isc" },
313 	{ }
314 };
315 MODULE_DEVICE_TABLE(of, atmel_isc_of_match);
316 #endif
317 
318 static struct platform_driver atmel_isc_driver = {
319 	.probe	= atmel_isc_probe,
320 	.remove	= atmel_isc_remove,
321 	.driver	= {
322 		.name		= ATMEL_ISC_NAME,
323 		.pm		= &atmel_isc_dev_pm_ops,
324 		.of_match_table = of_match_ptr(atmel_isc_of_match),
325 	},
326 };
327 
328 module_platform_driver(atmel_isc_driver);
329 
330 MODULE_AUTHOR("Songjun Wu");
331 MODULE_DESCRIPTION("The V4L2 driver for Atmel-ISC");
332 MODULE_LICENSE("GPL v2");
333