* \author Daniele Basile <asterix@develer.com>
*/
+#include "dac_sam3.h"
#include "cfg/cfg_dac.h"
#include <cfg/log.h>
#include <drv/dac.h>
-
#include <drv/irq_cm3.h>
+#include <cpu/types.h>
+
#include <io/cm3.h>
#include <string.h>
+struct DacHardware
+{
+ uint16_t channels;
+ uint32_t rate;
+ bool end;
+};
+
+struct DacHardware dac_hw;
+
+#if CONFIG_DAC_TIMER == DACC_TRGSEL_TIO_CH0 /* Select Timer counter TIO Channel 0 */
+ #define DAC_TC_ID TC0_ID
+ #define DAC_TC_CCR TC0_CCR0
+ #define DAC_TC_IDR TC0_IDR0
+ #define DAC_TC_CMR TC0_CMR0
+ #define DAC_TC_SR TC0_SR0
+ #define DAC_TC_RA TC0_RA0
+ #define DAC_TC_RC TC0_RC0
+#elif CONFIG_DAC_TIMER == DACC_TRGSEL_TIO_CH1 /* Select Timer counter TIO Channel 1 */
+ #define DAC_TC_ID TC1_ID
+ #define DAC_TC_CCR TC0_CCR1
+ #define DAC_TC_IDR TC0_IDR1
+ #define DAC_TC_CMR TC0_CMR1
+ #define DAC_TC_SR TC0_SR1
+ #define DAC_TC_RA TC0_RA1
+ #define DAC_TC_RC TC0_RC1
+#elif CONFIG_DAC_TIMER == DACC_TRGSEL_TIO_CH2 /* Select Timer counter TIO Channel 2 */
+ #define DAC_TC_ID TC2_ID
+ #define DAC_TC_CCR TC0_CCR2
+ #define DAC_TC_IDR TC0_IDR2
+ #define DAC_TC_CMR TC0_CMR2
+ #define DAC_TC_SR TC0_SR2
+ #define DAC_TC_RA TC0_RA2
+ #define DAC_TC_RC TC0_RC2
+#elif CONFIG_DAC_TIMER == DACC_TRGSEL_PWM0 || CONFIG_DAC_TIMER == DACC_TRGSEL_PWM1
+ #error unimplemented pwm triger select.
+#endif
+
+INLINE void tc_setup(uint32_t freq, size_t n_sample)
+{
+ pmc_periphEnable(DAC_TC_ID);
+
+ /* Disable TC clock */
+ DAC_TC_CCR = TC_CCR_CLKDIS;
+ /* Disable interrupts */
+ DAC_TC_IDR = 0xFFFFFFFF;
+ /* Clear status register */
+ volatile uint32_t dummy = DAC_TC_SR;
+ (void)dummy;
+
+ /*
+ * Setup the timer counter:
+ * - select clock TCLK1 (MCK/2)
+ * - enable wave form mode
+ * - RA compare effect SET
+ * - RC compare effect CLEAR
+ * - UP mode with automatic trigger on RC Compare
+ */
+ DAC_TC_CMR = TC_TIMER_CLOCK1 | BV(TC_CMR_WAVE) | TC_CMR_ACPA_SET | TC_CMR_ACPC_CLEAR | BV(TC_CMR_CPCTRG);
+
+ /*
+ * Compute the sample frequency
+ * the RC counter will update every MCK/2 (see above)
+ * so to convert one sample at the user freq we generate
+ * the trigger every TC_CLK / (numer_of_sample * user_freq)
+ * where TC_CLK = MCK / 2.
+ */
+ uint32_t rc = DIV_ROUND((CPU_FREQ / 2), n_sample * freq);
+ DAC_TC_RC = rc;
+ /* generate the square wave with duty = 50% */
+ DAC_TC_RA = DIV_ROUND(50 * rc, 100);
+
+ PIOB_PDR = BV(25);
+ PIO_PERIPH_SEL(PIOB_BASE, BV(25), PIO_PERIPH_B);
+}
+
+INLINE void tc_start(void)
+{
+ DAC_TC_CCR = BV(TC_CCR_CLKEN)| BV(TC_CCR_SWTRG);
+}
+INLINE void tc_stop(void)
+{
+ DAC_TC_CCR = BV(TC_CCR_CLKDIS);
+}
-static int sam3x_dac_write(DacContext *ctx, unsigned channel, uint16_t sample)
+static int sam3x_dac_write(struct Dac *dac, unsigned channel, uint16_t sample)
{
- ASSERT(channel <= 1);
+ (void)dac;
+
+ ASSERT(channel <= DAC_MAXCH);
DACC_MR |= (channel << DACC_USER_SEL_SHIFT) & DACC_USER_SEL_MASK;
DACC_CHER |= BV(channel);
return 0;
}
-static void sam3x_dac_setCh(struct DacContext *ctx, uint32_t mask)
+static void sam3x_dac_setCh(struct Dac *dac, uint32_t mask)
{
+ /* we have only the ch0 and ch1 */
+ ASSERT(mask < BV(3));
+ dac->hw->channels = mask;
}
-static void sam3x_dac_setSampleRate(struct DacContext *ctx, uint32_t rate)
+static void sam3x_dac_setSampleRate(struct Dac *dac, uint32_t rate)
{
+ (void)dac;
+
+ /* Eneble hw trigger */
+ DACC_MR |= BV(DACC_TRGEN) | (CONFIG_DAC_TIMER << DACC_TRGSEL_SHIFT);
+ dac->hw->rate = rate;
}
-static void sam3x_dac_conversion(struct DacContext *ctx, void *buf, size_t len)
+static void sam3x_dac_conversion(struct Dac *dac, void *buf, size_t len)
{
+ if (dac->hw->channels & BV(DACC_CH0))
+ DACC_MR |= (DACC_CH0 << DACC_USER_SEL_SHIFT) & DACC_USER_SEL_MASK;
+
+ if (dac->hw->channels & BV(DACC_CH1))
+ DACC_MR |= (DACC_CH1 << DACC_USER_SEL_SHIFT) & DACC_USER_SEL_MASK;
+
+ DACC_CHER |= dac->hw->channels;
+
+ /* setup timer and start it */
+ tc_setup(dac->hw->rate, len);
+ tc_start();
+
+ /* Setup dma and start it */
DACC_TPR = (uint32_t)buf ;
DACC_TCR = len;
DACC_PTCR |= BV(DACC_PTCR_TXTEN);
}
-static bool sam3x_dac_isFinished(struct DacContext *ctx)
+static bool sam3x_dac_isFinished(struct Dac *dac)
{
+ (void)dac;
+ return 0;
}
-static void sam3x_dac_start(struct DacContext *ctx, void *buf, size_t len, size_t slicelen)
+static void sam3x_dac_start(struct Dac *dac, void *buf, size_t len, size_t slice_len)
{
+ (void)dac;
+ (void)buf;
+ (void)len;
+ (void)slice_len;
}
-static void sam3x_dac_stop(struct DacContext *ctx)
+static void sam3x_dac_stop(struct Dac *dac)
{
+ (void)dac;
}
-void dac_init(struct DacContext *ctx)
+void dac_init(struct Dac *dac)
{
- ctx->write = sam3x_dac_write;
- ctx->setCh = sam3x_dac_setCh;
- ctx->setSampleRate = sam3x_dac_setSampleRate;
- ctx->conversion = sam3x_dac_conversion;
- ctx->isFinished = sam3x_dac_isFinished;
- ctx->start = sam3x_dac_start;
- ctx->stop = sam3x_dac_stop;
-
- /* Clock ADC peripheral */
+ /* Fill the virtual table */
+ dac->ctx.write = sam3x_dac_write;
+ dac->ctx.setCh = sam3x_dac_setCh;
+ dac->ctx.setSampleRate = sam3x_dac_setSampleRate;
+ dac->ctx.conversion = sam3x_dac_conversion;
+ dac->ctx.isFinished = sam3x_dac_isFinished;
+ dac->ctx.start = sam3x_dac_start;
+ dac->ctx.stop = sam3x_dac_stop;
+ dac->ctx._type = DAC_SAM3X;
+ dac->hw = &dac_hw;
+
+ /* Clock DAC peripheral */
pmc_periphEnable(DACC_ID);
+ /* Reset hw */
DACC_CR |= BV(DACC_SWRST);
DACC_MR = 0;
- /* Refresh period */
- DACC_MR |= (16 << DACC_REFRESH_SHIFT) & DACC_REFRESH_MASK;
- /* Start up */
- DACC_MR |= (DACC_MR_STARTUP_0 << DACC_STARTUP_SHIFT) & DACC_STARTUP_MASK;
-
+ /* Configure the dac */
+ DACC_MR |= (CONFIG_DAC_REFRESH << DACC_REFRESH_SHIFT) & DACC_REFRESH_MASK;
+ DACC_MR |= (CONFIG_DAC_STARTUP << DACC_STARTUP_SHIFT) & DACC_STARTUP_MASK;
}