Sensoray 526 analogy driver

PATCH In review Alessio Margan @ IIT 2 participants 2 messages Jan 7, 2010

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Alessio Margan @ IIT

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2010-01-07 19:15 UTC #0 lore raw

PATCH 1/1 Sensoray 526 analogy driver

Hi,

I've got a doubt about s526 driver on reading analog input.

I read analog data in this way

sampl_t data;
a4l_insn_t insn_tab = {
.type = A4L_INSN_READ,
.idx_subd = idx_subd,
.chan_desc = CHAN(idx_chan),
.data_size = sizeof(data),
.data = &data};

/* Sends the read instruction to the Analogy layer */ ret = a4l_snd_insn(&dsc, &insn_tab);

on driver side data_size is the number of samples not the nr of byte to read, the driver expect data_size to be the number of samples and data to be a vector of samples

uint16_t *data = (uint16_t *)insn->data;

/* convert n samples */
for (n = 0; n < insn->data_size; n++) {
/* trigger conversion */
outw(value, ADDR_REG(REG_ADC));
a4l_info(dev, "s526_ai_rinsn: Wrote 0x%04x to ADC\n", value); a4l_info(dev, "s526_ai_rinsn: ADC reg=0x%04x\n", inw(ADDR_REG(REG_ADC)));

#define TIMEOUT 100

/* wait for conversion to end */
for (i = 0; i < TIMEOUT; i++) {
status = inw(ADDR_REG(REG_ISR));
if (status & ISR_ADC_DONE) {
outw(ISR_ADC_DONE, ADDR_REG(REG_ISR));
break;
}
}
if (i == TIMEOUT) {
a4l_warn(dev, "s526_ai_rinsn: ADC(0x%04x) timeout\n", inw(ADDR_REG(REG_ISR))); return -ETIMEDOUT;
}

/* read data */
d = inw(ADDR_REG(REG_ADD));
a4l_info(dev, "s526_ai_rinsn: AI[%d]=0x%04x\n", n, (unsigned short)(d & 0xFFFF));

/* munge data */
data[n] = d ^ 0x8000;
}

TIA

Alessio

Signature · 15 lines

ISTITUTO ITALIANO
DI TECNOLOGIA

Alessio Margan
/Senior Technician/
mail me <mailto:[email protected]>

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Alexis Berlemont

2010-01-07 20:52 UTC #1 lore raw

Hi,

Quoted 14 lines · Alessio Margan @ IIT wrote:

Hi,
I've got a doubt about s526 driver on reading analog input.
I read analog data in this way
sampl_t data;
a4l_insn_t insn_tab = {
.type = A4L_INSN_READ,
.idx_subd = idx_subd,
.chan_desc = CHAN(idx_chan),
.data_size = sizeof(data),
.data = &data};

Quoted 5 lines

/* Sends the read instruction to the Analogy layer */ ret = a4l_snd_insn(&dsc, &insn_tab);
on driver side data_size is the number of samples not the nr of byte to read, the driver expect data_size to be the number of samples and data to be a vector of samples

You are right. There is a bug in the driver. The field data_size is not the acquisition count but the size of all the acquisitions in bytes.

So we should see:
for (n = 0; n < insn->data_size / sizeof(uint16_t); n++) {

I will fix it tonight.

Quoted 29 lines

uint16_t *data = (uint16_t *)insn->data;
/* convert n samples */
for (n = 0; n < insn->data_size; n++) {
/* trigger conversion */
outw(value, ADDR_REG(REG_ADC));
a4l_info(dev, "s526_ai_rinsn: Wrote 0x%04x to ADC\n", value); a4l_info(dev, "s526_ai_rinsn: ADC reg=0x%04x\n", inw(ADDR_REG(REG_ADC)));
#define TIMEOUT 100
/* wait for conversion to end */
for (i = 0; i < TIMEOUT; i++) {
status = inw(ADDR_REG(REG_ISR));
if (status & ISR_ADC_DONE) {
outw(ISR_ADC_DONE, ADDR_REG(REG_ISR));
break;
}
}
if (i == TIMEOUT) {
a4l_warn(dev, "s526_ai_rinsn: ADC(0x%04x) timeout\n", inw(ADDR_REG(REG_ISR))); return -ETIMEDOUT;
}
/* read data */
d = inw(ADDR_REG(REG_ADD));
a4l_info(dev, "s526_ai_rinsn: AI[%d]=0x%04x\n", n, (unsigned short)(d & 0xFFFF));

Quoted 8 lines

/* munge data */
data[n] = d ^ 0x8000;
}
TIA
Alessio

Alexis.