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 <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/init.h>
22
23 #include "cx23885.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 "%s/0: " fmt, dev->name, ## arg);\
36 } while (0)
37
38 /* ------------------------------------------------------------------ */
39
40 #define VBI_LINE_LENGTH 1440
41 #define VBI_NTSC_LINE_COUNT 12
42 #define VBI_PAL_LINE_COUNT 18
43
44
cx23885_vbi_fmt(struct file * file,void * priv,struct v4l2_format * f)45 int cx23885_vbi_fmt(struct file *file, void *priv,
46 struct v4l2_format *f)
47 {
48 struct cx23885_dev *dev = video_drvdata(file);
49
50 f->fmt.vbi.sampling_rate = 27000000;
51 f->fmt.vbi.samples_per_line = VBI_LINE_LENGTH;
52 f->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY;
53 f->fmt.vbi.offset = 0;
54 f->fmt.vbi.flags = 0;
55 if (dev->tvnorm & V4L2_STD_525_60) {
56 /* ntsc */
57 f->fmt.vbi.start[0] = V4L2_VBI_ITU_525_F1_START + 9;
58 f->fmt.vbi.start[1] = V4L2_VBI_ITU_525_F2_START + 9;
59 f->fmt.vbi.count[0] = VBI_NTSC_LINE_COUNT;
60 f->fmt.vbi.count[1] = VBI_NTSC_LINE_COUNT;
61 } else if (dev->tvnorm & V4L2_STD_625_50) {
62 /* pal */
63 f->fmt.vbi.start[0] = V4L2_VBI_ITU_625_F1_START + 5;
64 f->fmt.vbi.start[1] = V4L2_VBI_ITU_625_F2_START + 5;
65 f->fmt.vbi.count[0] = VBI_PAL_LINE_COUNT;
66 f->fmt.vbi.count[1] = VBI_PAL_LINE_COUNT;
67 }
68
69 return 0;
70 }
71
72 /* We're given the Video Interrupt status register.
73 * The cx23885_video_irq() func has already validated
74 * the potential error bits, we just need to
75 * deal with vbi payload and return indication if
76 * we actually processed any payload.
77 */
cx23885_vbi_irq(struct cx23885_dev * dev,u32 status)78 int cx23885_vbi_irq(struct cx23885_dev *dev, u32 status)
79 {
80 u32 count;
81 int handled = 0;
82
83 if (status & VID_BC_MSK_VBI_RISCI1) {
84 dprintk(1, "%s() VID_BC_MSK_VBI_RISCI1\n", __func__);
85 spin_lock(&dev->slock);
86 count = cx_read(VID_A_GPCNT);
87 cx23885_video_wakeup(dev, &dev->vbiq, count);
88 spin_unlock(&dev->slock);
89 handled++;
90 }
91
92 return handled;
93 }
94
cx23885_start_vbi_dma(struct cx23885_dev * dev,struct cx23885_dmaqueue * q,struct cx23885_buffer * buf)95 static int cx23885_start_vbi_dma(struct cx23885_dev *dev,
96 struct cx23885_dmaqueue *q,
97 struct cx23885_buffer *buf)
98 {
99 dprintk(1, "%s()\n", __func__);
100
101 /* setup fifo + format */
102 cx23885_sram_channel_setup(dev, &dev->sram_channels[SRAM_CH02],
103 VBI_LINE_LENGTH, buf->risc.dma);
104
105 /* reset counter */
106 cx_write(VID_A_GPCNT_CTL, 3);
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
queue_setup(struct vb2_queue * q,const struct v4l2_format * fmt,unsigned int * num_buffers,unsigned int * num_planes,unsigned int sizes[],void * alloc_ctxs[])124 static int queue_setup(struct vb2_queue *q, const struct v4l2_format *fmt,
125 unsigned int *num_buffers, unsigned int *num_planes,
126 unsigned int sizes[], void *alloc_ctxs[])
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
buffer_prepare(struct vb2_buffer * vb)138 static int buffer_prepare(struct vb2_buffer *vb)
139 {
140 struct cx23885_dev *dev = vb->vb2_queue->drv_priv;
141 struct cx23885_buffer *buf = container_of(vb,
142 struct cx23885_buffer, vb);
143 struct sg_table *sgt = vb2_dma_sg_plane_desc(vb, 0);
144 unsigned lines = VBI_PAL_LINE_COUNT;
145 int ret;
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 ret = dma_map_sg(&dev->pci->dev, sgt->sgl, sgt->nents, DMA_FROM_DEVICE);
155 if (!ret)
156 return -EIO;
157
158 cx23885_risc_vbibuffer(dev->pci, &buf->risc,
159 sgt->sgl,
160 0, VBI_LINE_LENGTH * lines,
161 VBI_LINE_LENGTH, 0,
162 lines);
163 return 0;
164 }
165
buffer_finish(struct vb2_buffer * vb)166 static void buffer_finish(struct vb2_buffer *vb)
167 {
168 struct cx23885_dev *dev = vb->vb2_queue->drv_priv;
169 struct cx23885_buffer *buf = container_of(vb,
170 struct cx23885_buffer, vb);
171 struct sg_table *sgt = vb2_dma_sg_plane_desc(vb, 0);
172
173 cx23885_free_buffer(vb->vb2_queue->drv_priv, buf);
174
175 dma_unmap_sg(&dev->pci->dev, sgt->sgl, sgt->nents, DMA_FROM_DEVICE);
176 }
177
178 /*
179 * The risc program for each buffer works as follows: it starts with a simple
180 * 'JUMP to addr + 12', which is effectively a NOP. Then the code to DMA the
181 * buffer follows and at the end we have a JUMP back to the start + 12 (skipping
182 * the initial JUMP).
183 *
184 * This is the risc program of the first buffer to be queued if the active list
185 * is empty and it just keeps DMAing this buffer without generating any
186 * interrupts.
187 *
188 * If a new buffer is added then the initial JUMP in the code for that buffer
189 * will generate an interrupt which signals that the previous buffer has been
190 * DMAed successfully and that it can be returned to userspace.
191 *
192 * It also sets the final jump of the previous buffer to the start of the new
193 * buffer, thus chaining the new buffer into the DMA chain. This is a single
194 * atomic u32 write, so there is no race condition.
195 *
196 * The end-result of all this that you only get an interrupt when a buffer
197 * is ready, so the control flow is very easy.
198 */
buffer_queue(struct vb2_buffer * vb)199 static void buffer_queue(struct vb2_buffer *vb)
200 {
201 struct cx23885_dev *dev = vb->vb2_queue->drv_priv;
202 struct cx23885_buffer *buf = container_of(vb, struct cx23885_buffer, vb);
203 struct cx23885_buffer *prev;
204 struct cx23885_dmaqueue *q = &dev->vbiq;
205 unsigned long flags;
206
207 buf->risc.cpu[1] = cpu_to_le32(buf->risc.dma + 12);
208 buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP | RISC_CNT_INC);
209 buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma + 12);
210 buf->risc.jmp[2] = cpu_to_le32(0); /* bits 63-32 */
211
212 if (list_empty(&q->active)) {
213 spin_lock_irqsave(&dev->slock, flags);
214 list_add_tail(&buf->queue, &q->active);
215 spin_unlock_irqrestore(&dev->slock, flags);
216 dprintk(2, "[%p/%d] vbi_queue - first active\n",
217 buf, buf->vb.v4l2_buf.index);
218
219 } else {
220 buf->risc.cpu[0] |= cpu_to_le32(RISC_IRQ1);
221 prev = list_entry(q->active.prev, struct cx23885_buffer,
222 queue);
223 spin_lock_irqsave(&dev->slock, flags);
224 list_add_tail(&buf->queue, &q->active);
225 spin_unlock_irqrestore(&dev->slock, flags);
226 prev->risc.jmp[1] = cpu_to_le32(buf->risc.dma);
227 dprintk(2, "[%p/%d] buffer_queue - append to active\n",
228 buf, buf->vb.v4l2_buf.index);
229 }
230 }
231
cx23885_start_streaming(struct vb2_queue * q,unsigned int count)232 static int cx23885_start_streaming(struct vb2_queue *q, unsigned int count)
233 {
234 struct cx23885_dev *dev = q->drv_priv;
235 struct cx23885_dmaqueue *dmaq = &dev->vbiq;
236 struct cx23885_buffer *buf = list_entry(dmaq->active.next,
237 struct cx23885_buffer, queue);
238
239 cx23885_start_vbi_dma(dev, dmaq, buf);
240 return 0;
241 }
242
cx23885_stop_streaming(struct vb2_queue * q)243 static void cx23885_stop_streaming(struct vb2_queue *q)
244 {
245 struct cx23885_dev *dev = q->drv_priv;
246 struct cx23885_dmaqueue *dmaq = &dev->vbiq;
247 unsigned long flags;
248
249 cx_clear(VID_A_DMA_CTL, 0x22); /* FIFO and RISC enable */
250 spin_lock_irqsave(&dev->slock, flags);
251 while (!list_empty(&dmaq->active)) {
252 struct cx23885_buffer *buf = list_entry(dmaq->active.next,
253 struct cx23885_buffer, queue);
254
255 list_del(&buf->queue);
256 vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
257 }
258 spin_unlock_irqrestore(&dev->slock, flags);
259 }
260
261
262 struct vb2_ops cx23885_vbi_qops = {
263 .queue_setup = queue_setup,
264 .buf_prepare = buffer_prepare,
265 .buf_finish = buffer_finish,
266 .buf_queue = buffer_queue,
267 .wait_prepare = vb2_ops_wait_prepare,
268 .wait_finish = vb2_ops_wait_finish,
269 .start_streaming = cx23885_start_streaming,
270 .stop_streaming = cx23885_stop_streaming,
271 };
272