*/
#include <common.h>
-#include <s3c2400.h>
+#include <asm/arch/s3c24x0_cpu.h>
+#include <asm/io.h>
+#include <div64.h>
#include "tsc2000.h"
-void spi_init(void)
+#include "Pt1000_temp_data.h"
+
+/* helper function */
+#define abs(value) (((value) < 0) ? ((value)*-1) : (value))
+
+/*
+ * Maximal allowed deviation between two immediate meassurments of an analog
+ * thermo channel. 1 DIGIT = 0.0276 °C. This is used to filter sporadic
+ * "jumps" in measurment.
+ */
+#define MAX_DEVIATION 18 /* unit: DIGITs of adc; 18 DIGIT = 0.5 °C */
+
+void tsc2000_spi_init(void)
{
- S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
- S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
+ struct s3c24x0_gpio * const gpio = s3c24x0_get_base_gpio();
+ struct s3c24x0_spi * const spi = s3c24x0_get_base_spi();
int i;
/* Configure I/O ports. */
- gpio->PDCON = (gpio->PDCON & 0xF3FFFF) | 0x040000;
+ gpio->PDCON = (gpio->PDCON & 0xF3FFFF) | 0x040000;
gpio->PGCON = (gpio->PGCON & 0x0F3FFF) | 0x008000;
gpio->PGCON = (gpio->PGCON & 0x0CFFFF) | 0x020000;
gpio->PGCON = (gpio->PGCON & 0x03FFFF) | 0x080000;
spi->ch[0].SPPRE = 0x1F; /* Baud-rate ca. 514kHz */
spi->ch[0].SPPIN = 0x01; /* SPI-MOSI holds Level after last bit */
spi->ch[0].SPCON = 0x1A; /* Polling, Prescaler, Master, CPOL=0,
- CPHA=1 */
+ CPHA=1 */
/* Dummy byte ensures clock to be low. */
for (i = 0; i < 10; i++) {
}
-static void spi_wait_transmit_done(void)
+void spi_wait_transmit_done(void)
{
- S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
+ struct s3c24x0_spi * const spi = s3c24x0_get_base_spi();
while (!(spi->ch[0].SPSTA & 0x01)); /* wait until transfer is done */
}
-static void tsc2000_write(unsigned short reg, unsigned short data)
+void tsc2000_write(unsigned short reg, unsigned short data)
{
- S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
+ struct s3c24x0_spi * const spi = s3c24x0_get_base_spi();
unsigned int command;
SET_CS_TOUCH();
command = reg;
- spi->ch[0].SPTDAT = (command & 0xFF00) >> 8;
+ spi->ch[0].SPTDAT = (command & 0xFF00) >> 8;
spi_wait_transmit_done();
spi->ch[0].SPTDAT = (command & 0x00FF);
spi_wait_transmit_done();
}
-static unsigned short tsc2000_read (unsigned short reg)
+unsigned short tsc2000_read (unsigned short reg)
{
unsigned short command, data;
- S3C24X0_SPI * const spi = S3C24X0_GetBase_SPI();
+ struct s3c24x0_spi * const spi = s3c24x0_get_base_spi();
SET_CS_TOUCH();
command = 0x8000 | reg;
- spi->ch[0].SPTDAT = (command & 0xFF00) >> 8;
+ spi->ch[0].SPTDAT = (command & 0xFF00) >> 8;
spi_wait_transmit_done();
spi->ch[0].SPTDAT = (command & 0x00FF);
spi_wait_transmit_done();
- spi->ch[0].SPTDAT = 0xFF;
+ spi->ch[0].SPTDAT = 0xFF;
spi_wait_transmit_done();
data = spi->ch[0].SPRDAT;
spi->ch[0].SPTDAT = 0xFF;
}
-static void tsc2000_set_mux (unsigned int channel)
+void tsc2000_set_mux (unsigned int channel)
{
- S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
+ struct s3c24x0_gpio * const gpio = s3c24x0_get_base_gpio();
CLR_MUX1_ENABLE; CLR_MUX2_ENABLE;
CLR_MUX3_ENABLE; CLR_MUX4_ENABLE;
}
-static void tsc2000_set_range (unsigned int range)
+void tsc2000_set_range (unsigned int range)
{
- S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
+ struct s3c24x0_gpio * const gpio = s3c24x0_get_base_gpio();
switch (range) {
case 1:
}
-static u16 tsc2000_read_channel (unsigned int channel)
+u16 tsc2000_read_channel (unsigned int channel)
{
u16 res;
tsc2000_set_mux(channel);
- udelay(3 * TSC2000_DELAY_BASE);
+ udelay(20 * TSC2000_DELAY_BASE);
tsc2000_write(TSC2000_REG_ADC, 0x2036);
- adc_wait_conversion_done ();
- res = tsc2000_read(TSC2000_REG_AUX1);
+ adc_wait_conversion_done ();
+ res = tsc2000_read(TSC2000_REG_AUX1);
return res;
}
s32 tsc2000_contact_temp (void)
{
long adc_pt1000, offset;
- long u_pt1000;
+ long u_pt1000;
long contact_temp;
+ long temp1, temp2;
-
- tsc2000_reg_init ();
+ tsc2000_reg_init ();
tsc2000_set_range (3);
- adc_pt1000 = tsc2000_read_channel (14);
- debug ("read channel 14 (pt1000 adc value): %ld\n", adc_pt1000);
-
- offset = tsc2000_read_channel (15);
- debug ("read channel 15 (offset): %ld\n", offset);
-
- /*
- * Formula for calculating voltage drop on PT1000 resistor: u_pt1000 =
- * x_range3 * (adc_raw - offset) / 10. Formula to calculate x_range3:
- * x_range3 = (2500 * (1000000 + err_vref + err_amp3)) / (4095*6). The
- * error correction Values err_vref and err_amp3 are assumed as 0 in
- * u-boot, because this could cause only a very small error (< 1%).
- */
- u_pt1000 = (101750 * (adc_pt1000 - offset)) / 10;
- debug ("u_pt1000: %ld\n", u_pt1000);
-
- if (tsc2000_interpolate(u_pt1000, Pt1000_temp_table,
- &contact_temp) == -1) {
- printf ("%s: error interpolating PT1000 vlaue\n",
- __FUNCTION__);
- return (-1000);
- }
- debug ("contact_temp: %ld\n", contact_temp);
+ /*
+ * Because of sporadic "jumps" in the measured adc values every
+ * channel is read two times. If there is a significant difference
+ * between the two measurements, then print an error and do a third
+ * measurement, because it is very unlikely that a successive third
+ * measurement goes also wrong.
+ */
+ temp1 = tsc2000_read_channel (14);
+ temp2 = tsc2000_read_channel (14);
+ if (abs(temp2 - temp1) < MAX_DEVIATION)
+ adc_pt1000 = temp2;
+ else {
+ printf ("%s: read adc value (channel 14) exceeded max allowed "
+ "deviation: %d * 0.0276 °C\n",
+ __FUNCTION__, MAX_DEVIATION);
+ printf ("adc value 1: %ld DIGITs\nadc value 2: %ld DIGITs\n",
+ temp1, temp2);
+ adc_pt1000 = tsc2000_read_channel (14);
+ printf ("use (third read) adc value: adc_pt1000 = "
+ "%ld DIGITs\n", adc_pt1000);
+ }
+ debug ("read channel 14 (pt1000 adc value): %ld\n", adc_pt1000);
+
+ temp1 = tsc2000_read_channel (15);
+ temp2 = tsc2000_read_channel (15);
+ if (abs(temp2 - temp1) < MAX_DEVIATION)
+ offset = temp2;
+ else {
+ printf ("%s: read adc value (channel 15) exceeded max allowed "
+ "deviation: %d * 0.0276 °C\n",
+ __FUNCTION__, MAX_DEVIATION);
+ printf ("adc value 1: %ld DIGITs\nadc value 2: %ld DIGITs\n",
+ temp1, temp2);
+ offset = tsc2000_read_channel (15);
+ printf ("use (third read) adc value: offset = %ld DIGITs\n",
+ offset);
+ }
+ debug ("read channel 15 (offset): %ld\n", offset);
+
+ /*
+ * Formula for calculating voltage drop on PT1000 resistor: u_pt1000 =
+ * x_range3 * (adc_raw - offset) / 10. Formula to calculate x_range3:
+ * x_range3 = (2500 * (1000000 + err_vref + err_amp3)) / (4095*6). The
+ * error correction Values err_vref and err_amp3 are assumed as 0 in
+ * u-boot, because this could cause only a very small error (< 1%).
+ */
+ u_pt1000 = (101750 * (adc_pt1000 - offset)) / 10;
+ debug ("u_pt1000: %ld\n", u_pt1000);
+
+ if (tsc2000_interpolate(u_pt1000, Pt1000_temp_table,
+ &contact_temp) == -1) {
+ printf ("%s: error interpolating PT1000 vlaue\n",
+ __FUNCTION__);
+ return (-1000);
+ }
+ debug ("contact_temp: %ld\n", contact_temp);
return contact_temp;
}
void tsc2000_reg_init (void)
{
- S3C24X0_GPIO * const gpio = S3C24X0_GetBase_GPIO();
+ struct s3c24x0_gpio * const gpio = s3c24x0_get_base_gpio();
tsc2000_write(TSC2000_REG_ADC, 0x2036);
tsc2000_write(TSC2000_REG_REF, 0x0011);
}
-static int tsc2000_interpolate(long value, long data[][2], long *result)
+int tsc2000_interpolate(long value, long data[][2], long *result)
{
int i;
+ unsigned long long val;
/* the data is sorted and the first element is upper
* limit so we can easily check for out-of-band values
result in 'long long'.
*/
- *result = data[i-1][1] +
- ((unsigned long long)(data[i][1] - data[i-1][1])
- * (unsigned long long)(value - data[i-1][0]))
- / (data[i][0] - data[i-1][0]);
+ val = ((unsigned long long)(data[i][1] - data[i-1][1])
+ * (unsigned long long)(value - data[i-1][0]));
+ do_div(val, (data[i][0] - data[i-1][0]));
+ *result = data[i-1][1] + val;
return 0;
}
-static void adc_wait_conversion_done(void)
+void adc_wait_conversion_done(void)
{
- while (!(tsc2000_read(TSC2000_REG_ADC) & (1 << 14)));
+ while (!(tsc2000_read(TSC2000_REG_ADC) & (1 << 14)));
}