1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Support for the camera device found on Marvell MMP processors; known
4 * to work with the Armada 610 as used in the OLPC 1.75 system.
5 *
6 * Copyright 2011 Jonathan Corbet <corbet@lwn.net>
7 * Copyright 2018 Lubomir Rintel <lkundrak@v3.sk>
8 */
9
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/spinlock.h>
15 #include <linux/slab.h>
16 #include <linux/videodev2.h>
17 #include <media/v4l2-device.h>
18 #include <linux/platform_data/media/mmp-camera.h>
19 #include <linux/device.h>
20 #include <linux/of.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/io.h>
25 #include <linux/list.h>
26 #include <linux/pm.h>
27 #include <linux/clk.h>
28
29 #include "mcam-core.h"
30
31 MODULE_ALIAS("platform:mmp-camera");
32 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
33 MODULE_DESCRIPTION("Support for the camera device found on Marvell MMP processors");
34 MODULE_LICENSE("GPL");
35
36 static char *mcam_clks[] = {"axi", "func", "phy"};
37
38 struct mmp_camera {
39 struct platform_device *pdev;
40 struct mcam_camera mcam;
41 struct list_head devlist;
42 struct clk *mipi_clk;
43 int irq;
44 };
45
mcam_to_cam(struct mcam_camera * mcam)46 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
47 {
48 return container_of(mcam, struct mmp_camera, mcam);
49 }
50
51 /*
52 * calc the dphy register values
53 * There are three dphy registers being used.
54 * dphy[0] - CSI2_DPHY3
55 * dphy[1] - CSI2_DPHY5
56 * dphy[2] - CSI2_DPHY6
57 * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
58 * or be calculated dynamically
59 */
mmpcam_calc_dphy(struct mcam_camera * mcam)60 static void mmpcam_calc_dphy(struct mcam_camera *mcam)
61 {
62 struct mmp_camera *cam = mcam_to_cam(mcam);
63 struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
64 struct device *dev = &cam->pdev->dev;
65 unsigned long tx_clk_esc;
66
67 /*
68 * If CSI2_DPHY3 is calculated dynamically,
69 * pdata->lane_clk should be already set
70 * either in the board driver statically
71 * or in the sensor driver dynamically.
72 */
73 /*
74 * dphy[0] - CSI2_DPHY3:
75 * bit 0 ~ bit 7: HS Term Enable.
76 * defines the time that the DPHY
77 * wait before enabling the data
78 * lane termination after detecting
79 * that the sensor has driven the data
80 * lanes to the LP00 bridge state.
81 * The value is calculated by:
82 * (Max T(D_TERM_EN)/Period(DDR)) - 1
83 * bit 8 ~ bit 15: HS_SETTLE
84 * Time interval during which the HS
85 * receiver shall ignore any Data Lane
86 * HS transitions.
87 * The value has been calibrated on
88 * different boards. It seems to work well.
89 *
90 * More detail please refer
91 * MIPI Alliance Spectification for D-PHY
92 * document for explanation of HS-SETTLE
93 * and D-TERM-EN.
94 */
95 switch (pdata->dphy3_algo) {
96 case DPHY3_ALGO_PXA910:
97 /*
98 * Calculate CSI2_DPHY3 algo for PXA910
99 */
100 pdata->dphy[0] =
101 (((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
102 | (1 + pdata->lane_clk * 35 / 1000);
103 break;
104 case DPHY3_ALGO_PXA2128:
105 /*
106 * Calculate CSI2_DPHY3 algo for PXA2128
107 */
108 pdata->dphy[0] =
109 (((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
110 | (1 + pdata->lane_clk * 35 / 1000);
111 break;
112 default:
113 /*
114 * Use default CSI2_DPHY3 value for PXA688/PXA988
115 */
116 dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
117 }
118
119 /*
120 * mipi_clk will never be changed, it is a fixed value on MMP
121 */
122 if (IS_ERR(cam->mipi_clk))
123 return;
124
125 /* get the escape clk, this is hard coded */
126 clk_prepare_enable(cam->mipi_clk);
127 tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;
128 clk_disable_unprepare(cam->mipi_clk);
129 /*
130 * dphy[2] - CSI2_DPHY6:
131 * bit 0 ~ bit 7: CK Term Enable
132 * Time for the Clock Lane receiver to enable the HS line
133 * termination. The value is calculated similarly with
134 * HS Term Enable
135 * bit 8 ~ bit 15: CK Settle
136 * Time interval during which the HS receiver shall ignore
137 * any Clock Lane HS transitions.
138 * The value is calibrated on the boards.
139 */
140 pdata->dphy[2] =
141 ((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
142 | (((38 * tx_clk_esc) / 1000 - 1) & 0xff);
143
144 dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
145 pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
146 }
147
mmpcam_irq(int irq,void * data)148 static irqreturn_t mmpcam_irq(int irq, void *data)
149 {
150 struct mcam_camera *mcam = data;
151 unsigned int irqs, handled;
152
153 spin_lock(&mcam->dev_lock);
154 irqs = mcam_reg_read(mcam, REG_IRQSTAT);
155 handled = mccic_irq(mcam, irqs);
156 spin_unlock(&mcam->dev_lock);
157 return IRQ_RETVAL(handled);
158 }
159
mcam_init_clk(struct mcam_camera * mcam)160 static void mcam_init_clk(struct mcam_camera *mcam)
161 {
162 unsigned int i;
163
164 for (i = 0; i < NR_MCAM_CLK; i++) {
165 if (mcam_clks[i] != NULL) {
166 /* Some clks are not necessary on some boards
167 * We still try to run even it fails getting clk
168 */
169 mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]);
170 if (IS_ERR(mcam->clk[i]))
171 dev_warn(mcam->dev, "Could not get clk: %s\n",
172 mcam_clks[i]);
173 }
174 }
175 }
176
mmpcam_probe(struct platform_device * pdev)177 static int mmpcam_probe(struct platform_device *pdev)
178 {
179 struct mmp_camera *cam;
180 struct mcam_camera *mcam;
181 struct resource *res;
182 struct fwnode_handle *ep;
183 struct mmp_camera_platform_data *pdata;
184 struct v4l2_async_connection *asd;
185 int ret;
186
187 cam = devm_kzalloc(&pdev->dev, sizeof(*cam), GFP_KERNEL);
188 if (cam == NULL)
189 return -ENOMEM;
190 platform_set_drvdata(pdev, cam);
191 cam->pdev = pdev;
192 INIT_LIST_HEAD(&cam->devlist);
193
194 mcam = &cam->mcam;
195 mcam->calc_dphy = mmpcam_calc_dphy;
196 mcam->dev = &pdev->dev;
197 pdata = pdev->dev.platform_data;
198 if (pdata) {
199 mcam->mclk_src = pdata->mclk_src;
200 mcam->mclk_div = pdata->mclk_div;
201 mcam->bus_type = pdata->bus_type;
202 mcam->dphy = pdata->dphy;
203 mcam->lane = pdata->lane;
204 } else {
205 /*
206 * These are values that used to be hardcoded in mcam-core and
207 * work well on a OLPC XO 1.75 with a parallel bus sensor.
208 * If it turns out other setups make sense, the values should
209 * be obtained from the device tree.
210 */
211 mcam->mclk_src = 3;
212 mcam->mclk_div = 2;
213 }
214 if (mcam->bus_type == V4L2_MBUS_CSI2_DPHY) {
215 cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
216 if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
217 return PTR_ERR(cam->mipi_clk);
218 }
219 mcam->mipi_enabled = false;
220 mcam->chip_id = MCAM_ARMADA610;
221 mcam->buffer_mode = B_DMA_sg;
222 strscpy(mcam->bus_info, "platform:mmp-camera", sizeof(mcam->bus_info));
223 spin_lock_init(&mcam->dev_lock);
224 /*
225 * Get our I/O memory.
226 */
227 mcam->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
228 if (IS_ERR(mcam->regs))
229 return PTR_ERR(mcam->regs);
230 mcam->regs_size = resource_size(res);
231
232 mcam_init_clk(mcam);
233
234 /*
235 * Create a match of the sensor against its OF node.
236 */
237 ep = fwnode_graph_get_next_endpoint(of_fwnode_handle(pdev->dev.of_node),
238 NULL);
239 if (!ep)
240 return -ENODEV;
241
242 v4l2_async_nf_init(&mcam->notifier, &mcam->v4l2_dev);
243
244 asd = v4l2_async_nf_add_fwnode_remote(&mcam->notifier, ep,
245 struct v4l2_async_connection);
246 fwnode_handle_put(ep);
247 if (IS_ERR(asd)) {
248 ret = PTR_ERR(asd);
249 goto out;
250 }
251
252 /*
253 * Register the device with the core.
254 */
255 ret = mccic_register(mcam);
256 if (ret)
257 goto out;
258
259 /*
260 * Add OF clock provider.
261 */
262 ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get,
263 mcam->mclk);
264 if (ret) {
265 dev_err(&pdev->dev, "can't add DT clock provider\n");
266 goto out;
267 }
268
269 /*
270 * Finally, set up our IRQ now that the core is ready to
271 * deal with it.
272 */
273 ret = platform_get_irq(pdev, 0);
274 if (ret < 0)
275 goto out;
276 cam->irq = ret;
277 ret = devm_request_irq(&pdev->dev, cam->irq, mmpcam_irq, IRQF_SHARED,
278 "mmp-camera", mcam);
279 if (ret)
280 goto out;
281
282 pm_runtime_enable(&pdev->dev);
283 return 0;
284 out:
285 mccic_shutdown(mcam);
286
287 return ret;
288 }
289
mmpcam_remove(struct platform_device * pdev)290 static void mmpcam_remove(struct platform_device *pdev)
291 {
292 struct mmp_camera *cam = platform_get_drvdata(pdev);
293 struct mcam_camera *mcam = &cam->mcam;
294
295 mccic_shutdown(mcam);
296 pm_runtime_force_suspend(mcam->dev);
297 }
298
299 /*
300 * Suspend/resume support.
301 */
302
mmpcam_runtime_resume(struct device * dev)303 static int __maybe_unused mmpcam_runtime_resume(struct device *dev)
304 {
305 struct mmp_camera *cam = dev_get_drvdata(dev);
306 struct mcam_camera *mcam = &cam->mcam;
307 unsigned int i;
308
309 for (i = 0; i < NR_MCAM_CLK; i++) {
310 if (!IS_ERR(mcam->clk[i]))
311 clk_prepare_enable(mcam->clk[i]);
312 }
313
314 return 0;
315 }
316
mmpcam_runtime_suspend(struct device * dev)317 static int __maybe_unused mmpcam_runtime_suspend(struct device *dev)
318 {
319 struct mmp_camera *cam = dev_get_drvdata(dev);
320 struct mcam_camera *mcam = &cam->mcam;
321 int i;
322
323 for (i = NR_MCAM_CLK - 1; i >= 0; i--) {
324 if (!IS_ERR(mcam->clk[i]))
325 clk_disable_unprepare(mcam->clk[i]);
326 }
327
328 return 0;
329 }
330
mmpcam_suspend(struct device * dev)331 static int __maybe_unused mmpcam_suspend(struct device *dev)
332 {
333 struct mmp_camera *cam = dev_get_drvdata(dev);
334
335 if (!pm_runtime_suspended(dev))
336 mccic_suspend(&cam->mcam);
337 return 0;
338 }
339
mmpcam_resume(struct device * dev)340 static int __maybe_unused mmpcam_resume(struct device *dev)
341 {
342 struct mmp_camera *cam = dev_get_drvdata(dev);
343
344 if (!pm_runtime_suspended(dev))
345 return mccic_resume(&cam->mcam);
346 return 0;
347 }
348
349 static const struct dev_pm_ops mmpcam_pm_ops = {
350 SET_RUNTIME_PM_OPS(mmpcam_runtime_suspend, mmpcam_runtime_resume, NULL)
351 SET_SYSTEM_SLEEP_PM_OPS(mmpcam_suspend, mmpcam_resume)
352 };
353
354 static const struct of_device_id mmpcam_of_match[] = {
355 { .compatible = "marvell,mmp2-ccic", },
356 {},
357 };
358 MODULE_DEVICE_TABLE(of, mmpcam_of_match);
359
360 static struct platform_driver mmpcam_driver = {
361 .probe = mmpcam_probe,
362 .remove_new = mmpcam_remove,
363 .driver = {
364 .name = "mmp-camera",
365 .of_match_table = mmpcam_of_match,
366 .pm = &mmpcam_pm_ops,
367 }
368 };
369
370 module_platform_driver(mmpcam_driver);
371