1 /* 2 * Driver for the Conexant CX23885 PCIe bridge 3 * 4 * Copyright (c) 2007 Steven Toth <stoth@linuxtv.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * 15 * GNU General Public License for more details. 16 */ 17 18 #include "cx23885.h" 19 20 #include <linux/kernel.h> 21 #include <linux/module.h> 22 #include <linux/moduleparam.h> 23 #include <linux/init.h> 24 25 static unsigned int vbibufs = 4; 26 module_param(vbibufs, int, 0644); 27 MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32"); 28 29 static unsigned int vbi_debug; 30 module_param(vbi_debug, int, 0644); 31 MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]"); 32 33 #define dprintk(level, fmt, arg...)\ 34 do { if (vbi_debug >= level)\ 35 printk(KERN_DEBUG pr_fmt("%s: vbi:" fmt), \ 36 __func__, ##arg); \ 37 } while (0) 38 39 /* ------------------------------------------------------------------ */ 40 41 #define VBI_LINE_LENGTH 1440 42 #define VBI_NTSC_LINE_COUNT 12 43 #define VBI_PAL_LINE_COUNT 18 44 45 46 int cx23885_vbi_fmt(struct file *file, void *priv, 47 struct v4l2_format *f) 48 { 49 struct cx23885_dev *dev = video_drvdata(file); 50 51 f->fmt.vbi.sampling_rate = 27000000; 52 f->fmt.vbi.samples_per_line = VBI_LINE_LENGTH; 53 f->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY; 54 f->fmt.vbi.offset = 0; 55 f->fmt.vbi.flags = 0; 56 if (dev->tvnorm & V4L2_STD_525_60) { 57 /* ntsc */ 58 f->fmt.vbi.start[0] = V4L2_VBI_ITU_525_F1_START + 9; 59 f->fmt.vbi.start[1] = V4L2_VBI_ITU_525_F2_START + 9; 60 f->fmt.vbi.count[0] = VBI_NTSC_LINE_COUNT; 61 f->fmt.vbi.count[1] = VBI_NTSC_LINE_COUNT; 62 } else if (dev->tvnorm & V4L2_STD_625_50) { 63 /* pal */ 64 f->fmt.vbi.start[0] = V4L2_VBI_ITU_625_F1_START + 5; 65 f->fmt.vbi.start[1] = V4L2_VBI_ITU_625_F2_START + 5; 66 f->fmt.vbi.count[0] = VBI_PAL_LINE_COUNT; 67 f->fmt.vbi.count[1] = VBI_PAL_LINE_COUNT; 68 } 69 70 return 0; 71 } 72 73 /* We're given the Video Interrupt status register. 74 * The cx23885_video_irq() func has already validated 75 * the potential error bits, we just need to 76 * deal with vbi payload and return indication if 77 * we actually processed any payload. 78 */ 79 int cx23885_vbi_irq(struct cx23885_dev *dev, u32 status) 80 { 81 u32 count; 82 int handled = 0; 83 84 if (status & VID_BC_MSK_VBI_RISCI1) { 85 dprintk(1, "%s() VID_BC_MSK_VBI_RISCI1\n", __func__); 86 spin_lock(&dev->slock); 87 count = cx_read(VBI_A_GPCNT); 88 cx23885_video_wakeup(dev, &dev->vbiq, count); 89 spin_unlock(&dev->slock); 90 handled++; 91 } 92 93 return handled; 94 } 95 96 static int cx23885_start_vbi_dma(struct cx23885_dev *dev, 97 struct cx23885_dmaqueue *q, 98 struct cx23885_buffer *buf) 99 { 100 dprintk(1, "%s()\n", __func__); 101 102 /* setup fifo + format */ 103 cx23885_sram_channel_setup(dev, &dev->sram_channels[SRAM_CH02], 104 VBI_LINE_LENGTH, buf->risc.dma); 105 106 /* reset counter */ 107 cx_write(VID_A_VBI_CTRL, 3); 108 cx_write(VBI_A_GPCNT_CTL, 3); 109 q->count = 0; 110 111 /* enable irq */ 112 cx23885_irq_add_enable(dev, 0x01); 113 cx_set(VID_A_INT_MSK, 0x000022); 114 115 /* start dma */ 116 cx_set(DEV_CNTRL2, (1<<5)); 117 cx_set(VID_A_DMA_CTL, 0x22); /* FIFO and RISC enable */ 118 119 return 0; 120 } 121 122 /* ------------------------------------------------------------------ */ 123 124 static int queue_setup(struct vb2_queue *q, 125 unsigned int *num_buffers, unsigned int *num_planes, 126 unsigned int sizes[], struct device *alloc_devs[]) 127 { 128 struct cx23885_dev *dev = q->drv_priv; 129 unsigned lines = VBI_PAL_LINE_COUNT; 130 131 if (dev->tvnorm & V4L2_STD_525_60) 132 lines = VBI_NTSC_LINE_COUNT; 133 *num_planes = 1; 134 sizes[0] = lines * VBI_LINE_LENGTH * 2; 135 return 0; 136 } 137 138 static int buffer_prepare(struct vb2_buffer *vb) 139 { 140 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 141 struct cx23885_dev *dev = vb->vb2_queue->drv_priv; 142 struct cx23885_buffer *buf = container_of(vbuf, 143 struct cx23885_buffer, vb); 144 struct sg_table *sgt = vb2_dma_sg_plane_desc(vb, 0); 145 unsigned lines = VBI_PAL_LINE_COUNT; 146 147 if (dev->tvnorm & V4L2_STD_525_60) 148 lines = VBI_NTSC_LINE_COUNT; 149 150 if (vb2_plane_size(vb, 0) < lines * VBI_LINE_LENGTH * 2) 151 return -EINVAL; 152 vb2_set_plane_payload(vb, 0, lines * VBI_LINE_LENGTH * 2); 153 154 cx23885_risc_vbibuffer(dev->pci, &buf->risc, 155 sgt->sgl, 156 0, VBI_LINE_LENGTH * lines, 157 VBI_LINE_LENGTH, 0, 158 lines); 159 return 0; 160 } 161 162 static void buffer_finish(struct vb2_buffer *vb) 163 { 164 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 165 struct cx23885_buffer *buf = container_of(vbuf, 166 struct cx23885_buffer, vb); 167 168 cx23885_free_buffer(vb->vb2_queue->drv_priv, buf); 169 } 170 171 /* 172 * The risc program for each buffer works as follows: it starts with a simple 173 * 'JUMP to addr + 12', which is effectively a NOP. Then the code to DMA the 174 * buffer follows and at the end we have a JUMP back to the start + 12 (skipping 175 * the initial JUMP). 176 * 177 * This is the risc program of the first buffer to be queued if the active list 178 * is empty and it just keeps DMAing this buffer without generating any 179 * interrupts. 180 * 181 * If a new buffer is added then the initial JUMP in the code for that buffer 182 * will generate an interrupt which signals that the previous buffer has been 183 * DMAed successfully and that it can be returned to userspace. 184 * 185 * It also sets the final jump of the previous buffer to the start of the new 186 * buffer, thus chaining the new buffer into the DMA chain. This is a single 187 * atomic u32 write, so there is no race condition. 188 * 189 * The end-result of all this that you only get an interrupt when a buffer 190 * is ready, so the control flow is very easy. 191 */ 192 static void buffer_queue(struct vb2_buffer *vb) 193 { 194 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); 195 struct cx23885_dev *dev = vb->vb2_queue->drv_priv; 196 struct cx23885_buffer *buf = container_of(vbuf, 197 struct cx23885_buffer, vb); 198 struct cx23885_buffer *prev; 199 struct cx23885_dmaqueue *q = &dev->vbiq; 200 unsigned long flags; 201 202 buf->risc.cpu[1] = cpu_to_le32(buf->risc.dma + 12); 203 buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP | RISC_CNT_INC); 204 buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma + 12); 205 buf->risc.jmp[2] = cpu_to_le32(0); /* bits 63-32 */ 206 207 if (list_empty(&q->active)) { 208 spin_lock_irqsave(&dev->slock, flags); 209 list_add_tail(&buf->queue, &q->active); 210 spin_unlock_irqrestore(&dev->slock, flags); 211 dprintk(2, "[%p/%d] vbi_queue - first active\n", 212 buf, buf->vb.vb2_buf.index); 213 214 } else { 215 buf->risc.cpu[0] |= cpu_to_le32(RISC_IRQ1); 216 prev = list_entry(q->active.prev, struct cx23885_buffer, 217 queue); 218 spin_lock_irqsave(&dev->slock, flags); 219 list_add_tail(&buf->queue, &q->active); 220 spin_unlock_irqrestore(&dev->slock, flags); 221 prev->risc.jmp[1] = cpu_to_le32(buf->risc.dma); 222 dprintk(2, "[%p/%d] buffer_queue - append to active\n", 223 buf, buf->vb.vb2_buf.index); 224 } 225 } 226 227 static int cx23885_start_streaming(struct vb2_queue *q, unsigned int count) 228 { 229 struct cx23885_dev *dev = q->drv_priv; 230 struct cx23885_dmaqueue *dmaq = &dev->vbiq; 231 struct cx23885_buffer *buf = list_entry(dmaq->active.next, 232 struct cx23885_buffer, queue); 233 234 cx23885_start_vbi_dma(dev, dmaq, buf); 235 return 0; 236 } 237 238 static void cx23885_stop_streaming(struct vb2_queue *q) 239 { 240 struct cx23885_dev *dev = q->drv_priv; 241 struct cx23885_dmaqueue *dmaq = &dev->vbiq; 242 unsigned long flags; 243 244 cx_clear(VID_A_DMA_CTL, 0x22); /* FIFO and RISC enable */ 245 spin_lock_irqsave(&dev->slock, flags); 246 while (!list_empty(&dmaq->active)) { 247 struct cx23885_buffer *buf = list_entry(dmaq->active.next, 248 struct cx23885_buffer, queue); 249 250 list_del(&buf->queue); 251 vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR); 252 } 253 spin_unlock_irqrestore(&dev->slock, flags); 254 } 255 256 257 const struct vb2_ops cx23885_vbi_qops = { 258 .queue_setup = queue_setup, 259 .buf_prepare = buffer_prepare, 260 .buf_finish = buffer_finish, 261 .buf_queue = buffer_queue, 262 .wait_prepare = vb2_ops_wait_prepare, 263 .wait_finish = vb2_ops_wait_finish, 264 .start_streaming = cx23885_start_streaming, 265 .stop_streaming = cx23885_stop_streaming, 266 }; 267