2 * Functions to access the TSC2000 controller on TRAB board (used for scanning
5 * Copyright (C) 2003 Martin Krause, TQ-Systems GmbH, martin.krause@tqs.de
7 * Copyright (C) 2002 DENX Software Engineering, Wolfgang Denk, wd@denx.de
9 * See file CREDITS for list of people who contributed to this
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License as
14 * published by the Free Software Foundation; either version 2 of
15 * the License, or (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
33 #include "Pt1000_temp_data.h"
36 #define abs(value) (((value) < 0) ? ((value)*-1) : (value))
39 * Maximal allowed deviation between two immediate meassurments of an analog
40 * thermo channel. 1 DIGIT = 0.0276 °C. This is used to filter sporadic
41 * "jumps" in measurment.
43 #define MAX_DEVIATION 18 /* unit: DIGITs of adc; 18 DIGIT = 0.5 °C */
45 void tsc2000_spi_init(void)
47 S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
48 S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
51 /* Configure I/O ports. */
52 gpio->PDCON = (gpio->PDCON & 0xF3FFFF) | 0x040000;
53 gpio->PGCON = (gpio->PGCON & 0x0F3FFF) | 0x008000;
54 gpio->PGCON = (gpio->PGCON & 0x0CFFFF) | 0x020000;
55 gpio->PGCON = (gpio->PGCON & 0x03FFFF) | 0x080000;
59 spi->ch[0].SPPRE = 0x1F; /* Baud-rate ca. 514kHz */
60 spi->ch[0].SPPIN = 0x01; /* SPI-MOSI holds Level after last bit */
61 spi->ch[0].SPCON = 0x1A; /* Polling, Prescaler, Master, CPOL=0,
64 /* Dummy byte ensures clock to be low. */
65 for (i = 0; i < 10; i++) {
66 spi->ch[0].SPTDAT = 0xFF;
68 spi_wait_transmit_done();
72 void spi_wait_transmit_done(void)
74 S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
76 while (!(spi->ch[0].SPSTA & 0x01)); /* wait until transfer is done */
80 void tsc2000_write(unsigned short reg, unsigned short data)
82 S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
87 spi->ch[0].SPTDAT = (command & 0xFF00) >> 8;
88 spi_wait_transmit_done();
89 spi->ch[0].SPTDAT = (command & 0x00FF);
90 spi_wait_transmit_done();
91 spi->ch[0].SPTDAT = (data & 0xFF00) >> 8;
92 spi_wait_transmit_done();
93 spi->ch[0].SPTDAT = (data & 0x00FF);
94 spi_wait_transmit_done();
100 unsigned short tsc2000_read (unsigned short reg)
102 unsigned short command, data;
103 S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
106 command = 0x8000 | reg;
108 spi->ch[0].SPTDAT = (command & 0xFF00) >> 8;
109 spi_wait_transmit_done();
110 spi->ch[0].SPTDAT = (command & 0x00FF);
111 spi_wait_transmit_done();
113 spi->ch[0].SPTDAT = 0xFF;
114 spi_wait_transmit_done();
115 data = spi->ch[0].SPRDAT;
116 spi->ch[0].SPTDAT = 0xFF;
117 spi_wait_transmit_done();
120 return (spi->ch[0].SPRDAT & 0x0FF) | (data << 8);
124 void tsc2000_set_mux (unsigned int channel)
126 S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
128 CLR_MUX1_ENABLE; CLR_MUX2_ENABLE;
129 CLR_MUX3_ENABLE; CLR_MUX4_ENABLE;
201 void tsc2000_set_range (unsigned int range)
203 S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
207 CLR_SEL_TEMP_V_0; SET_SEL_TEMP_V_1;
208 CLR_SEL_TEMP_V_2; CLR_SEL_TEMP_V_3;
211 CLR_SEL_TEMP_V_0; CLR_SEL_TEMP_V_1;
212 CLR_SEL_TEMP_V_2; SET_SEL_TEMP_V_3;
215 SET_SEL_TEMP_V_0; CLR_SEL_TEMP_V_1;
216 SET_SEL_TEMP_V_2; CLR_SEL_TEMP_V_3;
222 u16 tsc2000_read_channel (unsigned int channel)
226 tsc2000_set_mux(channel);
227 udelay(20 * TSC2000_DELAY_BASE);
229 tsc2000_write(TSC2000_REG_ADC, 0x2036);
230 adc_wait_conversion_done ();
231 res = tsc2000_read(TSC2000_REG_AUX1);
236 s32 tsc2000_contact_temp (void)
238 long adc_pt1000, offset;
244 tsc2000_set_range (3);
247 * Because of sporadic "jumps" in the measured adc values every
248 * channel is read two times. If there is a significant difference
249 * between the two measurements, then print an error and do a third
250 * measurement, because it is very unlikely that a successive third
251 * measurement goes also wrong.
253 temp1 = tsc2000_read_channel (14);
254 temp2 = tsc2000_read_channel (14);
255 if (abs(temp2 - temp1) < MAX_DEVIATION)
258 printf ("%s: read adc value (channel 14) exceeded max allowed "
259 "deviation: %d * 0.0276 °C\n",
260 __FUNCTION__, MAX_DEVIATION);
261 printf ("adc value 1: %ld DIGITs\nadc value 2: %ld DIGITs\n",
263 adc_pt1000 = tsc2000_read_channel (14);
264 printf ("use (third read) adc value: adc_pt1000 = "
265 "%ld DIGITs\n", adc_pt1000);
267 debug ("read channel 14 (pt1000 adc value): %ld\n", adc_pt1000);
269 temp1 = tsc2000_read_channel (15);
270 temp2 = tsc2000_read_channel (15);
271 if (abs(temp2 - temp1) < MAX_DEVIATION)
274 printf ("%s: read adc value (channel 15) exceeded max allowed "
275 "deviation: %d * 0.0276 °C\n",
276 __FUNCTION__, MAX_DEVIATION);
277 printf ("adc value 1: %ld DIGITs\nadc value 2: %ld DIGITs\n",
279 offset = tsc2000_read_channel (15);
280 printf ("use (third read) adc value: offset = %ld DIGITs\n",
283 debug ("read channel 15 (offset): %ld\n", offset);
286 * Formula for calculating voltage drop on PT1000 resistor: u_pt1000 =
287 * x_range3 * (adc_raw - offset) / 10. Formula to calculate x_range3:
288 * x_range3 = (2500 * (1000000 + err_vref + err_amp3)) / (4095*6). The
289 * error correction Values err_vref and err_amp3 are assumed as 0 in
290 * u-boot, because this could cause only a very small error (< 1%).
292 u_pt1000 = (101750 * (adc_pt1000 - offset)) / 10;
293 debug ("u_pt1000: %ld\n", u_pt1000);
295 if (tsc2000_interpolate(u_pt1000, Pt1000_temp_table,
296 &contact_temp) == -1) {
297 printf ("%s: error interpolating PT1000 vlaue\n",
301 debug ("contact_temp: %ld\n", contact_temp);
307 void tsc2000_reg_init (void)
309 S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
311 tsc2000_write(TSC2000_REG_ADC, 0x2036);
312 tsc2000_write(TSC2000_REG_REF, 0x0011);
313 tsc2000_write(TSC2000_REG_DACCTL, 0x0000);
329 tsc2000_set_range(0);
333 int tsc2000_interpolate(long value, long data[][2], long *result)
336 unsigned long long val;
338 /* the data is sorted and the first element is upper
339 * limit so we can easily check for out-of-band values
341 if (data[0][0] < value || data[1][0] > value)
345 while (data[i][0] < value)
348 /* To prevent overflow we have to store the intermediate
349 result in 'long long'.
352 val = ((unsigned long long)(data[i][1] - data[i-1][1])
353 * (unsigned long long)(value - data[i-1][0]));
354 do_div(val, (data[i][0] - data[i-1][0]));
355 *result = data[i-1][1] + val;
361 void adc_wait_conversion_done(void)
363 while (!(tsc2000_read(TSC2000_REG_ADC) & (1 << 14)));