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_LICENSE("GPL");
34
35 static char *mcam_clks[] = {"axi", "func", "phy"};
36
37 struct mmp_camera {
38 struct platform_device *pdev;
39 struct mcam_camera mcam;
40 struct list_head devlist;
41 struct clk *mipi_clk;
42 int irq;
43 };
44
mcam_to_cam(struct mcam_camera * mcam)45 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
46 {
47 return container_of(mcam, struct mmp_camera, mcam);
48 }
49
50 /*
51 * calc the dphy register values
52 * There are three dphy registers being used.
53 * dphy[0] - CSI2_DPHY3
54 * dphy[1] - CSI2_DPHY5
55 * dphy[2] - CSI2_DPHY6
56 * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
57 * or be calculated dynamically
58 */
mmpcam_calc_dphy(struct mcam_camera * mcam)59 static void mmpcam_calc_dphy(struct mcam_camera *mcam)
60 {
61 struct mmp_camera *cam = mcam_to_cam(mcam);
62 struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
63 struct device *dev = &cam->pdev->dev;
64 unsigned long tx_clk_esc;
65
66 /*
67 * If CSI2_DPHY3 is calculated dynamically,
68 * pdata->lane_clk should be already set
69 * either in the board driver statically
70 * or in the sensor driver dynamically.
71 */
72 /*
73 * dphy[0] - CSI2_DPHY3:
74 * bit 0 ~ bit 7: HS Term Enable.
75 * defines the time that the DPHY
76 * wait before enabling the data
77 * lane termination after detecting
78 * that the sensor has driven the data
79 * lanes to the LP00 bridge state.
80 * The value is calculated by:
81 * (Max T(D_TERM_EN)/Period(DDR)) - 1
82 * bit 8 ~ bit 15: HS_SETTLE
83 * Time interval during which the HS
84 * receiver shall ignore any Data Lane
85 * HS transitions.
86 * The value has been calibrated on
87 * different boards. It seems to work well.
88 *
89 * More detail please refer
90 * MIPI Alliance Spectification for D-PHY
91 * document for explanation of HS-SETTLE
92 * and D-TERM-EN.
93 */
94 switch (pdata->dphy3_algo) {
95 case DPHY3_ALGO_PXA910:
96 /*
97 * Calculate CSI2_DPHY3 algo for PXA910
98 */
99 pdata->dphy[0] =
100 (((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
101 | (1 + pdata->lane_clk * 35 / 1000);
102 break;
103 case DPHY3_ALGO_PXA2128:
104 /*
105 * Calculate CSI2_DPHY3 algo for PXA2128
106 */
107 pdata->dphy[0] =
108 (((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
109 | (1 + pdata->lane_clk * 35 / 1000);
110 break;
111 default:
112 /*
113 * Use default CSI2_DPHY3 value for PXA688/PXA988
114 */
115 dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
116 }
117
118 /*
119 * mipi_clk will never be changed, it is a fixed value on MMP
120 */
121 if (IS_ERR(cam->mipi_clk))
122 return;
123
124 /* get the escape clk, this is hard coded */
125 clk_prepare_enable(cam->mipi_clk);
126 tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;
127 clk_disable_unprepare(cam->mipi_clk);
128 /*
129 * dphy[2] - CSI2_DPHY6:
130 * bit 0 ~ bit 7: CK Term Enable
131 * Time for the Clock Lane receiver to enable the HS line
132 * termination. The value is calculated similarly with
133 * HS Term Enable
134 * bit 8 ~ bit 15: CK Settle
135 * Time interval during which the HS receiver shall ignore
136 * any Clock Lane HS transitions.
137 * The value is calibrated on the boards.
138 */
139 pdata->dphy[2] =
140 ((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
141 | (((38 * tx_clk_esc) / 1000 - 1) & 0xff);
142
143 dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
144 pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
145 }
146
mmpcam_irq(int irq,void * data)147 static irqreturn_t mmpcam_irq(int irq, void *data)
148 {
149 struct mcam_camera *mcam = data;
150 unsigned int irqs, handled;
151
152 spin_lock(&mcam->dev_lock);
153 irqs = mcam_reg_read(mcam, REG_IRQSTAT);
154 handled = mccic_irq(mcam, irqs);
155 spin_unlock(&mcam->dev_lock);
156 return IRQ_RETVAL(handled);
157 }
158
mcam_init_clk(struct mcam_camera * mcam)159 static void mcam_init_clk(struct mcam_camera *mcam)
160 {
161 unsigned int i;
162
163 for (i = 0; i < NR_MCAM_CLK; i++) {
164 if (mcam_clks[i] != NULL) {
165 /* Some clks are not necessary on some boards
166 * We still try to run even it fails getting clk
167 */
168 mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]);
169 if (IS_ERR(mcam->clk[i]))
170 dev_warn(mcam->dev, "Could not get clk: %s\n",
171 mcam_clks[i]);
172 }
173 }
174 }
175
mmpcam_probe(struct platform_device * pdev)176 static int mmpcam_probe(struct platform_device *pdev)
177 {
178 struct mmp_camera *cam;
179 struct mcam_camera *mcam;
180 struct resource *res;
181 struct fwnode_handle *ep;
182 struct mmp_camera_platform_data *pdata;
183 int ret;
184
185 cam = devm_kzalloc(&pdev->dev, sizeof(*cam), GFP_KERNEL);
186 if (cam == NULL)
187 return -ENOMEM;
188 platform_set_drvdata(pdev, cam);
189 cam->pdev = pdev;
190 INIT_LIST_HEAD(&cam->devlist);
191
192 mcam = &cam->mcam;
193 mcam->calc_dphy = mmpcam_calc_dphy;
194 mcam->dev = &pdev->dev;
195 pdata = pdev->dev.platform_data;
196 if (pdata) {
197 mcam->mclk_src = pdata->mclk_src;
198 mcam->mclk_div = pdata->mclk_div;
199 mcam->bus_type = pdata->bus_type;
200 mcam->dphy = pdata->dphy;
201 mcam->lane = pdata->lane;
202 } else {
203 /*
204 * These are values that used to be hardcoded in mcam-core and
205 * work well on a OLPC XO 1.75 with a parallel bus sensor.
206 * If it turns out other setups make sense, the values should
207 * be obtained from the device tree.
208 */
209 mcam->mclk_src = 3;
210 mcam->mclk_div = 2;
211 }
212 if (mcam->bus_type == V4L2_MBUS_CSI2_DPHY) {
213 cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
214 if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
215 return PTR_ERR(cam->mipi_clk);
216 }
217 mcam->mipi_enabled = false;
218 mcam->chip_id = MCAM_ARMADA610;
219 mcam->buffer_mode = B_DMA_sg;
220 strscpy(mcam->bus_info, "platform:mmp-camera", sizeof(mcam->bus_info));
221 spin_lock_init(&mcam->dev_lock);
222 /*
223 * Get our I/O memory.
224 */
225 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
226 mcam->regs = devm_ioremap_resource(&pdev->dev, res);
227 if (IS_ERR(mcam->regs))
228 return PTR_ERR(mcam->regs);
229 mcam->regs_size = resource_size(res);
230
231 mcam_init_clk(mcam);
232
233 /*
234 * Create a match of the sensor against its OF node.
235 */
236 ep = fwnode_graph_get_next_endpoint(of_fwnode_handle(pdev->dev.of_node),
237 NULL);
238 if (!ep)
239 return -ENODEV;
240
241 mcam->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
242 mcam->asd.match.fwnode = fwnode_graph_get_remote_port_parent(ep);
243
244 fwnode_handle_put(ep);
245
246 /*
247 * Register the device with the core.
248 */
249 ret = mccic_register(mcam);
250 if (ret)
251 return ret;
252
253 /*
254 * Add OF clock provider.
255 */
256 ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get,
257 mcam->mclk);
258 if (ret) {
259 dev_err(&pdev->dev, "can't add DT clock provider\n");
260 goto out;
261 }
262
263 /*
264 * Finally, set up our IRQ now that the core is ready to
265 * deal with it.
266 */
267 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
268 if (res == NULL) {
269 ret = -ENODEV;
270 goto out;
271 }
272 cam->irq = res->start;
273 ret = devm_request_irq(&pdev->dev, cam->irq, mmpcam_irq, IRQF_SHARED,
274 "mmp-camera", mcam);
275 if (ret)
276 goto out;
277
278 pm_runtime_enable(&pdev->dev);
279 return 0;
280 out:
281 fwnode_handle_put(mcam->asd.match.fwnode);
282 mccic_shutdown(mcam);
283
284 return ret;
285 }
286
287
mmpcam_remove(struct mmp_camera * cam)288 static int mmpcam_remove(struct mmp_camera *cam)
289 {
290 struct mcam_camera *mcam = &cam->mcam;
291
292 mccic_shutdown(mcam);
293 pm_runtime_force_suspend(mcam->dev);
294 return 0;
295 }
296
mmpcam_platform_remove(struct platform_device * pdev)297 static int mmpcam_platform_remove(struct platform_device *pdev)
298 {
299 struct mmp_camera *cam = platform_get_drvdata(pdev);
300
301 if (cam == NULL)
302 return -ENODEV;
303 return mmpcam_remove(cam);
304 }
305
306 /*
307 * Suspend/resume support.
308 */
309
310 #ifdef CONFIG_PM
mmpcam_runtime_resume(struct device * dev)311 static int mmpcam_runtime_resume(struct device *dev)
312 {
313 struct mmp_camera *cam = dev_get_drvdata(dev);
314 struct mcam_camera *mcam = &cam->mcam;
315 unsigned int i;
316
317 for (i = 0; i < NR_MCAM_CLK; i++) {
318 if (!IS_ERR(mcam->clk[i]))
319 clk_prepare_enable(mcam->clk[i]);
320 }
321
322 return 0;
323 }
324
mmpcam_runtime_suspend(struct device * dev)325 static int mmpcam_runtime_suspend(struct device *dev)
326 {
327 struct mmp_camera *cam = dev_get_drvdata(dev);
328 struct mcam_camera *mcam = &cam->mcam;
329 int i;
330
331 for (i = NR_MCAM_CLK - 1; i >= 0; i--) {
332 if (!IS_ERR(mcam->clk[i]))
333 clk_disable_unprepare(mcam->clk[i]);
334 }
335
336 return 0;
337 }
338
mmpcam_suspend(struct device * dev)339 static int __maybe_unused mmpcam_suspend(struct device *dev)
340 {
341 struct mmp_camera *cam = dev_get_drvdata(dev);
342
343 if (!pm_runtime_suspended(dev))
344 mccic_suspend(&cam->mcam);
345 return 0;
346 }
347
mmpcam_resume(struct device * dev)348 static int __maybe_unused mmpcam_resume(struct device *dev)
349 {
350 struct mmp_camera *cam = dev_get_drvdata(dev);
351
352 if (!pm_runtime_suspended(dev))
353 return mccic_resume(&cam->mcam);
354 return 0;
355 }
356 #endif
357
358 static const struct dev_pm_ops mmpcam_pm_ops = {
359 SET_RUNTIME_PM_OPS(mmpcam_runtime_suspend, mmpcam_runtime_resume, NULL)
360 SET_SYSTEM_SLEEP_PM_OPS(mmpcam_suspend, mmpcam_resume)
361 };
362
363 static const struct of_device_id mmpcam_of_match[] = {
364 { .compatible = "marvell,mmp2-ccic", },
365 {},
366 };
367 MODULE_DEVICE_TABLE(of, mmpcam_of_match);
368
369 static struct platform_driver mmpcam_driver = {
370 .probe = mmpcam_probe,
371 .remove = mmpcam_platform_remove,
372 .driver = {
373 .name = "mmp-camera",
374 .of_match_table = of_match_ptr(mmpcam_of_match),
375 .pm = &mmpcam_pm_ops,
376 }
377 };
378
379 module_platform_driver(mmpcam_driver);
380