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mc44s803.c
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1 /*
2  * Driver for Freescale MC44S803 Low Power CMOS Broadband Tuner
3  *
4  * Copyright (c) 2009 Jochen Friedrich <[email protected]>
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  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.=
20  */
21 
22 #include <linux/module.h>
23 #include <linux/delay.h>
24 #include <linux/dvb/frontend.h>
25 #include <linux/i2c.h>
26 #include <linux/slab.h>
27 
28 #include "dvb_frontend.h"
29 
30 #include "mc44s803.h"
31 #include "mc44s803_priv.h"
32 
33 #define mc_printk(level, format, arg...) \
34  printk(level "mc44s803: " format , ## arg)
35 
36 /* Writes a single register */
37 static int mc44s803_writereg(struct mc44s803_priv *priv, u32 val)
38 {
39  u8 buf[3];
40  struct i2c_msg msg = {
41  .addr = priv->cfg->i2c_address, .flags = 0, .buf = buf, .len = 3
42  };
43 
44  buf[0] = (val & 0xff0000) >> 16;
45  buf[1] = (val & 0xff00) >> 8;
46  buf[2] = (val & 0xff);
47 
48  if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
49  mc_printk(KERN_WARNING, "I2C write failed\n");
50  return -EREMOTEIO;
51  }
52  return 0;
53 }
54 
55 /* Reads a single register */
56 static int mc44s803_readreg(struct mc44s803_priv *priv, u8 reg, u32 *val)
57 {
58  u32 wval;
59  u8 buf[3];
60  int ret;
61  struct i2c_msg msg[] = {
62  { .addr = priv->cfg->i2c_address, .flags = I2C_M_RD,
63  .buf = buf, .len = 3 },
64  };
65 
68 
69  ret = mc44s803_writereg(priv, wval);
70  if (ret)
71  return ret;
72 
73  if (i2c_transfer(priv->i2c, msg, 1) != 1) {
74  mc_printk(KERN_WARNING, "I2C read failed\n");
75  return -EREMOTEIO;
76  }
77 
78  *val = (buf[0] << 16) | (buf[1] << 8) | buf[2];
79 
80  return 0;
81 }
82 
83 static int mc44s803_release(struct dvb_frontend *fe)
84 {
85  struct mc44s803_priv *priv = fe->tuner_priv;
86 
87  fe->tuner_priv = NULL;
88  kfree(priv);
89 
90  return 0;
91 }
92 
93 static int mc44s803_init(struct dvb_frontend *fe)
94 {
95  struct mc44s803_priv *priv = fe->tuner_priv;
96  u32 val;
97  int err;
98 
99  if (fe->ops.i2c_gate_ctrl)
100  fe->ops.i2c_gate_ctrl(fe, 1);
101 
102 /* Reset chip */
105 
106  err = mc44s803_writereg(priv, val);
107  if (err)
108  goto exit;
109 
111 
112  err = mc44s803_writereg(priv, val);
113  if (err)
114  goto exit;
115 
116 /* Power Up and Start Osc */
117 
121 
122  err = mc44s803_writereg(priv, val);
123  if (err)
124  goto exit;
125 
128 
129  err = mc44s803_writereg(priv, val);
130  if (err)
131  goto exit;
132 
133  msleep(10);
134 
138 
139  err = mc44s803_writereg(priv, val);
140  if (err)
141  goto exit;
142 
143  msleep(20);
144 
145 /* Setup Mixer */
146 
150 
151  err = mc44s803_writereg(priv, val);
152  if (err)
153  goto exit;
154 
155 /* Setup Cirquit Adjust */
156 
162  MC44S803_REG_SM(priv->cfg->dig_out, MC44S803_S1) |
166 
167  err = mc44s803_writereg(priv, val);
168  if (err)
169  goto exit;
170 
176  MC44S803_REG_SM(priv->cfg->dig_out, MC44S803_S1) |
178 
179  err = mc44s803_writereg(priv, val);
180  if (err)
181  goto exit;
182 
183 /* Setup Digtune */
184 
187 
188  err = mc44s803_writereg(priv, val);
189  if (err)
190  goto exit;
191 
192 /* Setup AGC */
193 
200 
201  err = mc44s803_writereg(priv, val);
202  if (err)
203  goto exit;
204 
205  if (fe->ops.i2c_gate_ctrl)
206  fe->ops.i2c_gate_ctrl(fe, 0);
207  return 0;
208 
209 exit:
210  if (fe->ops.i2c_gate_ctrl)
211  fe->ops.i2c_gate_ctrl(fe, 0);
212 
213  mc_printk(KERN_WARNING, "I/O Error\n");
214  return err;
215 }
216 
217 static int mc44s803_set_params(struct dvb_frontend *fe)
218 {
219  struct mc44s803_priv *priv = fe->tuner_priv;
221  u32 r1, r2, n1, n2, lo1, lo2, freq, val;
222  int err;
223 
224  priv->frequency = c->frequency;
225 
226  r1 = MC44S803_OSC / 1000000;
227  r2 = MC44S803_OSC / 100000;
228 
229  n1 = (c->frequency + MC44S803_IF1 + 500000) / 1000000;
230  freq = MC44S803_OSC / r1 * n1;
231  lo1 = ((60 * n1) + (r1 / 2)) / r1;
232  freq = freq - c->frequency;
233 
234  n2 = (freq - MC44S803_IF2 + 50000) / 100000;
235  lo2 = ((60 * n2) + (r2 / 2)) / r2;
236 
237  if (fe->ops.i2c_gate_ctrl)
238  fe->ops.i2c_gate_ctrl(fe, 1);
239 
244 
245  err = mc44s803_writereg(priv, val);
246  if (err)
247  goto exit;
248 
251 
252  err = mc44s803_writereg(priv, val);
253  if (err)
254  goto exit;
255 
258 
259  err = mc44s803_writereg(priv, val);
260  if (err)
261  goto exit;
262 
267 
268  err = mc44s803_writereg(priv, val);
269  if (err)
270  goto exit;
271 
276 
277  err = mc44s803_writereg(priv, val);
278  if (err)
279  goto exit;
280 
281  if (fe->ops.i2c_gate_ctrl)
282  fe->ops.i2c_gate_ctrl(fe, 0);
283 
284  return 0;
285 
286 exit:
287  if (fe->ops.i2c_gate_ctrl)
288  fe->ops.i2c_gate_ctrl(fe, 0);
289 
290  mc_printk(KERN_WARNING, "I/O Error\n");
291  return err;
292 }
293 
294 static int mc44s803_get_frequency(struct dvb_frontend *fe, u32 *frequency)
295 {
296  struct mc44s803_priv *priv = fe->tuner_priv;
297  *frequency = priv->frequency;
298  return 0;
299 }
300 
301 static int mc44s803_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
302 {
303  *frequency = MC44S803_IF2; /* 36.125 MHz */
304  return 0;
305 }
306 
307 static const struct dvb_tuner_ops mc44s803_tuner_ops = {
308  .info = {
309  .name = "Freescale MC44S803",
310  .frequency_min = 48000000,
311  .frequency_max = 1000000000,
312  .frequency_step = 100000,
313  },
314 
315  .release = mc44s803_release,
316  .init = mc44s803_init,
317  .set_params = mc44s803_set_params,
318  .get_frequency = mc44s803_get_frequency,
319  .get_if_frequency = mc44s803_get_if_frequency,
320 };
321 
322 /* This functions tries to identify a MC44S803 tuner by reading the ID
323  register. This is hasty. */
325  struct i2c_adapter *i2c, struct mc44s803_config *cfg)
326 {
327  struct mc44s803_priv *priv;
328  u32 reg;
329  u8 id;
330  int ret;
331 
332  reg = 0;
333 
334  priv = kzalloc(sizeof(struct mc44s803_priv), GFP_KERNEL);
335  if (priv == NULL)
336  return NULL;
337 
338  priv->cfg = cfg;
339  priv->i2c = i2c;
340  priv->fe = fe;
341 
342  if (fe->ops.i2c_gate_ctrl)
343  fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
344 
345  ret = mc44s803_readreg(priv, MC44S803_REG_ID, &reg);
346  if (ret)
347  goto error;
348 
349  id = MC44S803_REG_MS(reg, MC44S803_ID);
350 
351  if (id != 0x14) {
352  mc_printk(KERN_ERR, "unsupported ID "
353  "(%x should be 0x14)\n", id);
354  goto error;
355  }
356 
357  mc_printk(KERN_INFO, "successfully identified (ID = %x)\n", id);
358  memcpy(&fe->ops.tuner_ops, &mc44s803_tuner_ops,
359  sizeof(struct dvb_tuner_ops));
360 
361  fe->tuner_priv = priv;
362 
363  if (fe->ops.i2c_gate_ctrl)
364  fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
365 
366  return fe;
367 
368 error:
369  if (fe->ops.i2c_gate_ctrl)
370  fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
371 
372  kfree(priv);
373  return NULL;
374 }
376 
377 MODULE_AUTHOR("Jochen Friedrich");
378 MODULE_DESCRIPTION("Freescale MC44S803 silicon tuner driver");
379 MODULE_LICENSE("GPL");