1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2016 NextThing Co 4 * Copyright (C) 2016-2019 Bootlin 5 * 6 * Author: Maxime Ripard <maxime.ripard@bootlin.com> 7 */ 8 9 #include <linux/device.h> 10 #include <linux/interrupt.h> 11 #include <linux/list.h> 12 #include <linux/mutex.h> 13 #include <linux/spinlock.h> 14 #include <media/videobuf2-dma-contig.h> 15 #include <media/videobuf2-v4l2.h> 16 17 #include "sun4i_csi.h" 18 19 struct sun4i_csi_buffer { 20 struct vb2_v4l2_buffer vb; 21 struct list_head list; 22 }; 23 24 static inline struct sun4i_csi_buffer * 25 vb2_v4l2_to_csi_buffer(const struct vb2_v4l2_buffer *p) 26 { 27 return container_of(p, struct sun4i_csi_buffer, vb); 28 } 29 30 static inline struct sun4i_csi_buffer * 31 vb2_to_csi_buffer(const struct vb2_buffer *p) 32 { 33 return vb2_v4l2_to_csi_buffer(to_vb2_v4l2_buffer(p)); 34 } 35 36 static void sun4i_csi_capture_start(struct sun4i_csi *csi) 37 { 38 writel(CSI_CPT_CTRL_VIDEO_START, csi->regs + CSI_CPT_CTRL_REG); 39 } 40 41 static void sun4i_csi_capture_stop(struct sun4i_csi *csi) 42 { 43 writel(0, csi->regs + CSI_CPT_CTRL_REG); 44 } 45 46 static int sun4i_csi_queue_setup(struct vb2_queue *vq, 47 unsigned int *nbuffers, 48 unsigned int *nplanes, 49 unsigned int sizes[], 50 struct device *alloc_devs[]) 51 { 52 struct sun4i_csi *csi = vb2_get_drv_priv(vq); 53 unsigned int num_planes = csi->fmt.num_planes; 54 unsigned int i; 55 56 if (*nplanes) { 57 if (*nplanes != num_planes) 58 return -EINVAL; 59 60 for (i = 0; i < num_planes; i++) 61 if (sizes[i] < csi->fmt.plane_fmt[i].sizeimage) 62 return -EINVAL; 63 return 0; 64 } 65 66 *nplanes = num_planes; 67 for (i = 0; i < num_planes; i++) 68 sizes[i] = csi->fmt.plane_fmt[i].sizeimage; 69 70 return 0; 71 }; 72 73 static int sun4i_csi_buffer_prepare(struct vb2_buffer *vb) 74 { 75 struct sun4i_csi *csi = vb2_get_drv_priv(vb->vb2_queue); 76 unsigned int i; 77 78 for (i = 0; i < csi->fmt.num_planes; i++) { 79 unsigned long size = csi->fmt.plane_fmt[i].sizeimage; 80 81 if (vb2_plane_size(vb, i) < size) { 82 dev_err(csi->dev, "buffer too small (%lu < %lu)\n", 83 vb2_plane_size(vb, i), size); 84 return -EINVAL; 85 } 86 87 vb2_set_plane_payload(vb, i, size); 88 } 89 90 return 0; 91 } 92 93 static int sun4i_csi_setup_scratch_buffer(struct sun4i_csi *csi, 94 unsigned int slot) 95 { 96 dma_addr_t addr = csi->scratch.paddr; 97 unsigned int plane; 98 99 dev_dbg(csi->dev, 100 "No more available buffer, using the scratch buffer\n"); 101 102 for (plane = 0; plane < csi->fmt.num_planes; plane++) { 103 writel(addr, csi->regs + CSI_BUF_ADDR_REG(plane, slot)); 104 addr += csi->fmt.plane_fmt[plane].sizeimage; 105 } 106 107 csi->current_buf[slot] = NULL; 108 return 0; 109 } 110 111 static int sun4i_csi_buffer_fill_slot(struct sun4i_csi *csi, unsigned int slot) 112 { 113 struct sun4i_csi_buffer *c_buf; 114 struct vb2_v4l2_buffer *v_buf; 115 unsigned int plane; 116 117 /* 118 * We should never end up in a situation where we overwrite an 119 * already filled slot. 120 */ 121 if (WARN_ON(csi->current_buf[slot])) 122 return -EINVAL; 123 124 if (list_empty(&csi->buf_list)) 125 return sun4i_csi_setup_scratch_buffer(csi, slot); 126 127 c_buf = list_first_entry(&csi->buf_list, struct sun4i_csi_buffer, list); 128 list_del_init(&c_buf->list); 129 130 v_buf = &c_buf->vb; 131 csi->current_buf[slot] = v_buf; 132 133 for (plane = 0; plane < csi->fmt.num_planes; plane++) { 134 dma_addr_t buf_addr; 135 136 buf_addr = vb2_dma_contig_plane_dma_addr(&v_buf->vb2_buf, 137 plane); 138 writel(buf_addr, csi->regs + CSI_BUF_ADDR_REG(plane, slot)); 139 } 140 141 return 0; 142 } 143 144 static int sun4i_csi_buffer_fill_all(struct sun4i_csi *csi) 145 { 146 unsigned int slot; 147 int ret; 148 149 for (slot = 0; slot < CSI_MAX_BUFFER; slot++) { 150 ret = sun4i_csi_buffer_fill_slot(csi, slot); 151 if (ret) 152 return ret; 153 } 154 155 return 0; 156 } 157 158 static void sun4i_csi_buffer_mark_done(struct sun4i_csi *csi, 159 unsigned int slot, 160 unsigned int sequence) 161 { 162 struct vb2_v4l2_buffer *v_buf; 163 164 if (!csi->current_buf[slot]) { 165 dev_dbg(csi->dev, "Scratch buffer was used, ignoring..\n"); 166 return; 167 } 168 169 v_buf = csi->current_buf[slot]; 170 v_buf->field = csi->fmt.field; 171 v_buf->sequence = sequence; 172 v_buf->vb2_buf.timestamp = ktime_get_ns(); 173 vb2_buffer_done(&v_buf->vb2_buf, VB2_BUF_STATE_DONE); 174 175 csi->current_buf[slot] = NULL; 176 } 177 178 static int sun4i_csi_buffer_flip(struct sun4i_csi *csi, unsigned int sequence) 179 { 180 u32 reg = readl(csi->regs + CSI_BUF_CTRL_REG); 181 unsigned int next; 182 183 /* Our next buffer is not the current buffer */ 184 next = !(reg & CSI_BUF_CTRL_DBS); 185 186 /* Report the previous buffer as done */ 187 sun4i_csi_buffer_mark_done(csi, next, sequence); 188 189 /* Put a new buffer in there */ 190 return sun4i_csi_buffer_fill_slot(csi, next); 191 } 192 193 static void sun4i_csi_buffer_queue(struct vb2_buffer *vb) 194 { 195 struct sun4i_csi *csi = vb2_get_drv_priv(vb->vb2_queue); 196 struct sun4i_csi_buffer *buf = vb2_to_csi_buffer(vb); 197 unsigned long flags; 198 199 spin_lock_irqsave(&csi->qlock, flags); 200 list_add_tail(&buf->list, &csi->buf_list); 201 spin_unlock_irqrestore(&csi->qlock, flags); 202 } 203 204 static void return_all_buffers(struct sun4i_csi *csi, 205 enum vb2_buffer_state state) 206 { 207 struct sun4i_csi_buffer *buf, *node; 208 unsigned int slot; 209 210 list_for_each_entry_safe(buf, node, &csi->buf_list, list) { 211 vb2_buffer_done(&buf->vb.vb2_buf, state); 212 list_del(&buf->list); 213 } 214 215 for (slot = 0; slot < CSI_MAX_BUFFER; slot++) { 216 struct vb2_v4l2_buffer *v_buf = csi->current_buf[slot]; 217 218 if (!v_buf) 219 continue; 220 221 vb2_buffer_done(&v_buf->vb2_buf, state); 222 csi->current_buf[slot] = NULL; 223 } 224 } 225 226 static int sun4i_csi_start_streaming(struct vb2_queue *vq, unsigned int count) 227 { 228 struct sun4i_csi *csi = vb2_get_drv_priv(vq); 229 struct v4l2_mbus_config_parallel *bus = &csi->bus; 230 const struct sun4i_csi_format *csi_fmt; 231 unsigned long href_pol, pclk_pol, vref_pol; 232 unsigned long flags; 233 unsigned int i; 234 int ret; 235 236 csi_fmt = sun4i_csi_find_format(&csi->fmt.pixelformat, NULL); 237 if (!csi_fmt) 238 return -EINVAL; 239 240 dev_dbg(csi->dev, "Starting capture\n"); 241 242 csi->sequence = 0; 243 244 /* 245 * We need a scratch buffer in case where we'll not have any 246 * more buffer queued so that we don't error out. One of those 247 * cases is when you end up at the last frame to capture, you 248 * don't have any buffer queued any more, and yet it doesn't 249 * really matter since you'll never reach the next buffer. 250 * 251 * Since we support the multi-planar API, we need to have a 252 * buffer for each plane. Allocating a single one large enough 253 * to hold all the buffers is simpler, so let's go for that. 254 */ 255 csi->scratch.size = 0; 256 for (i = 0; i < csi->fmt.num_planes; i++) 257 csi->scratch.size += csi->fmt.plane_fmt[i].sizeimage; 258 259 csi->scratch.vaddr = dma_alloc_coherent(csi->dev, 260 csi->scratch.size, 261 &csi->scratch.paddr, 262 GFP_KERNEL); 263 if (!csi->scratch.vaddr) { 264 dev_err(csi->dev, "Failed to allocate scratch buffer\n"); 265 ret = -ENOMEM; 266 goto err_clear_dma_queue; 267 } 268 269 ret = video_device_pipeline_alloc_start(&csi->vdev); 270 if (ret < 0) 271 goto err_free_scratch_buffer; 272 273 spin_lock_irqsave(&csi->qlock, flags); 274 275 /* Setup timings */ 276 writel(CSI_WIN_CTRL_W_ACTIVE(csi->fmt.width * 2), 277 csi->regs + CSI_WIN_CTRL_W_REG); 278 writel(CSI_WIN_CTRL_H_ACTIVE(csi->fmt.height), 279 csi->regs + CSI_WIN_CTRL_H_REG); 280 281 /* 282 * This hardware uses [HV]REF instead of [HV]SYNC. Based on the 283 * provided timing diagrams in the manual, positive polarity 284 * equals active high [HV]REF. 285 * 286 * When the back porch is 0, [HV]REF is more or less equivalent 287 * to [HV]SYNC inverted. 288 */ 289 href_pol = !!(bus->flags & V4L2_MBUS_HSYNC_ACTIVE_LOW); 290 vref_pol = !!(bus->flags & V4L2_MBUS_VSYNC_ACTIVE_LOW); 291 pclk_pol = !!(bus->flags & V4L2_MBUS_PCLK_SAMPLE_RISING); 292 writel(CSI_CFG_INPUT_FMT(csi_fmt->input) | 293 CSI_CFG_OUTPUT_FMT(csi_fmt->output) | 294 CSI_CFG_VREF_POL(vref_pol) | 295 CSI_CFG_HREF_POL(href_pol) | 296 CSI_CFG_PCLK_POL(pclk_pol), 297 csi->regs + CSI_CFG_REG); 298 299 /* Setup buffer length */ 300 writel(csi->fmt.plane_fmt[0].bytesperline, 301 csi->regs + CSI_BUF_LEN_REG); 302 303 /* Prepare our buffers in hardware */ 304 ret = sun4i_csi_buffer_fill_all(csi); 305 if (ret) { 306 spin_unlock_irqrestore(&csi->qlock, flags); 307 goto err_disable_pipeline; 308 } 309 310 /* Enable double buffering */ 311 writel(CSI_BUF_CTRL_DBE, csi->regs + CSI_BUF_CTRL_REG); 312 313 /* Clear the pending interrupts */ 314 writel(CSI_INT_FRM_DONE, csi->regs + CSI_INT_STA_REG); 315 316 /* Enable frame done interrupt */ 317 writel(CSI_INT_FRM_DONE, csi->regs + CSI_INT_EN_REG); 318 319 sun4i_csi_capture_start(csi); 320 321 spin_unlock_irqrestore(&csi->qlock, flags); 322 323 ret = v4l2_subdev_call(csi->src_subdev, video, s_stream, 1); 324 if (ret < 0 && ret != -ENOIOCTLCMD) 325 goto err_disable_device; 326 327 return 0; 328 329 err_disable_device: 330 sun4i_csi_capture_stop(csi); 331 332 err_disable_pipeline: 333 video_device_pipeline_stop(&csi->vdev); 334 335 err_free_scratch_buffer: 336 dma_free_coherent(csi->dev, csi->scratch.size, csi->scratch.vaddr, 337 csi->scratch.paddr); 338 339 err_clear_dma_queue: 340 spin_lock_irqsave(&csi->qlock, flags); 341 return_all_buffers(csi, VB2_BUF_STATE_QUEUED); 342 spin_unlock_irqrestore(&csi->qlock, flags); 343 344 return ret; 345 } 346 347 static void sun4i_csi_stop_streaming(struct vb2_queue *vq) 348 { 349 struct sun4i_csi *csi = vb2_get_drv_priv(vq); 350 unsigned long flags; 351 352 dev_dbg(csi->dev, "Stopping capture\n"); 353 354 v4l2_subdev_call(csi->src_subdev, video, s_stream, 0); 355 sun4i_csi_capture_stop(csi); 356 357 /* Release all active buffers */ 358 spin_lock_irqsave(&csi->qlock, flags); 359 return_all_buffers(csi, VB2_BUF_STATE_ERROR); 360 spin_unlock_irqrestore(&csi->qlock, flags); 361 362 video_device_pipeline_stop(&csi->vdev); 363 364 dma_free_coherent(csi->dev, csi->scratch.size, csi->scratch.vaddr, 365 csi->scratch.paddr); 366 } 367 368 static const struct vb2_ops sun4i_csi_qops = { 369 .queue_setup = sun4i_csi_queue_setup, 370 .buf_prepare = sun4i_csi_buffer_prepare, 371 .buf_queue = sun4i_csi_buffer_queue, 372 .start_streaming = sun4i_csi_start_streaming, 373 .stop_streaming = sun4i_csi_stop_streaming, 374 .wait_prepare = vb2_ops_wait_prepare, 375 .wait_finish = vb2_ops_wait_finish, 376 }; 377 378 static irqreturn_t sun4i_csi_irq(int irq, void *data) 379 { 380 struct sun4i_csi *csi = data; 381 u32 reg; 382 383 reg = readl(csi->regs + CSI_INT_STA_REG); 384 385 /* Acknowledge the interrupts */ 386 writel(reg, csi->regs + CSI_INT_STA_REG); 387 388 if (!(reg & CSI_INT_FRM_DONE)) 389 return IRQ_HANDLED; 390 391 spin_lock(&csi->qlock); 392 if (sun4i_csi_buffer_flip(csi, csi->sequence++)) { 393 dev_warn(csi->dev, "%s: Flip failed\n", __func__); 394 sun4i_csi_capture_stop(csi); 395 } 396 spin_unlock(&csi->qlock); 397 398 return IRQ_HANDLED; 399 } 400 401 int sun4i_csi_dma_register(struct sun4i_csi *csi, int irq) 402 { 403 struct vb2_queue *q = &csi->queue; 404 int ret; 405 int i; 406 407 spin_lock_init(&csi->qlock); 408 mutex_init(&csi->lock); 409 410 INIT_LIST_HEAD(&csi->buf_list); 411 for (i = 0; i < CSI_MAX_BUFFER; i++) 412 csi->current_buf[i] = NULL; 413 414 q->min_buffers_needed = 3; 415 q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE; 416 q->io_modes = VB2_MMAP | VB2_DMABUF; 417 q->lock = &csi->lock; 418 q->drv_priv = csi; 419 q->buf_struct_size = sizeof(struct sun4i_csi_buffer); 420 q->ops = &sun4i_csi_qops; 421 q->mem_ops = &vb2_dma_contig_memops; 422 q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; 423 q->dev = csi->dev; 424 425 ret = vb2_queue_init(q); 426 if (ret < 0) { 427 dev_err(csi->dev, "failed to initialize VB2 queue\n"); 428 goto err_free_mutex; 429 } 430 431 ret = v4l2_device_register(csi->dev, &csi->v4l); 432 if (ret) { 433 dev_err(csi->dev, "Couldn't register the v4l2 device\n"); 434 goto err_free_mutex; 435 } 436 437 ret = devm_request_irq(csi->dev, irq, sun4i_csi_irq, 0, 438 dev_name(csi->dev), csi); 439 if (ret) { 440 dev_err(csi->dev, "Couldn't register our interrupt\n"); 441 goto err_unregister_device; 442 } 443 444 return 0; 445 446 err_unregister_device: 447 v4l2_device_unregister(&csi->v4l); 448 449 err_free_mutex: 450 mutex_destroy(&csi->lock); 451 return ret; 452 } 453 454 void sun4i_csi_dma_unregister(struct sun4i_csi *csi) 455 { 456 v4l2_device_unregister(&csi->v4l); 457 mutex_destroy(&csi->lock); 458 } 459