diff options
Diffstat (limited to 'openpcd/firmware/src/os/pwm.c')
| -rw-r--r-- | openpcd/firmware/src/os/pwm.c | 165 |
1 files changed, 0 insertions, 165 deletions
diff --git a/openpcd/firmware/src/os/pwm.c b/openpcd/firmware/src/os/pwm.c deleted file mode 100644 index e05699b..0000000 --- a/openpcd/firmware/src/os/pwm.c +++ /dev/null @@ -1,165 +0,0 @@ -/* AT91SAM7 PWM routines for OpenPCD / OpenPICC - * - * (C) 2006 by Harald Welte <hwelte@hmw-consulting.de> - * - */ - -#include <lib_AT91SAM7.h> -#include <AT91SAM7.h> -#include <sys/types.h> -#include <errno.h> -#include <openpcd.h> -#include <os/usb_handler.h> -#include <os/pcd_enumerate.h> -#include <os/req_ctx.h> -#include <os/dbgu.h> -#include "../openpcd.h" - -#define Hz -#define kHz *1000 Hz -#define MHz *1000 kHz -#define MCLK (48 MHz) - -#if 1 -#define DEBUGPWM DEBUGPCRF -#else -#define DEBUGPWM(x, args...) -#endif - -static AT91PS_PWMC pwm = AT91C_BASE_PWMC; - -/* find highest bit set. returns bit (32..1) or 0 in case no bit set */ -static int fhs(u_int32_t val) -{ - int i; - - for (i = 32; i > 0; i--) { - if (val & (1 << (i-1))) - return i; - } - - return 0; -} - -/* set frequency of PWM signal to freq */ -int pwm_freq_set(int channel, u_int32_t freq) -{ - /* in order to get maximum resolution, the pre-scaler must be set to - * something like freq << 16. However, the mimimum pre-scaled frequency - * we can get is MCLK (48MHz), the minimum is MCLK/(1024*255) = - * 48MHz/261120 = 183Hz */ - u_int32_t overall_div; - u_int32_t presc_total; - u_int8_t cpre = 0; - u_int16_t cprd; - - if (freq > MCLK) - return -ERANGE; - - overall_div = MCLK / freq; - DEBUGPCRF("mclk=%u, freq=%u, overall_div=%u", MCLK, freq, overall_div); - - if (overall_div > 0x7fff) { - /* divisor is larger than half the maximum CPRD register, we - * have to configure prescalers */ - presc_total = overall_div >> 15; - - /* find highest 2^n fitting in prescaler (highest bit set) */ - cpre = fhs(presc_total); - if (cpre > 0) { - /* subtract one, because of fhs semantics */ - cpre--; - } - cprd = overall_div / (1 << cpre); - } else - cprd = overall_div; - - DEBUGPCRF("cpre=%u, cprd=%u", cpre, cprd); - AT91F_PWMC_CfgChannel(AT91C_BASE_PWMC, channel, - cpre|AT91C_PWMC_CPOL, cprd, 1); - - return 0; -} - -void pwm_start(int channel) -{ - AT91F_PWMC_StartChannel(AT91C_BASE_PWMC, (1 << channel)); -} - -void pwm_stop(int channel) -{ - AT91F_PWMC_StopChannel(AT91C_BASE_PWMC, (1 << channel)); -} - -void pwm_duty_set_percent(int channel, u_int16_t duty) -{ - u_int32_t tmp = pwm->PWMC_CH[channel].PWMC_CPRDR & 0xffff; - - tmp = tmp << 16; /* extend value by 2^16 */ - tmp = tmp / 100; /* tmp = 1 % of extended cprd */ - tmp = duty * tmp; /* tmp = 'duty' % of extended cprd */ - tmp = tmp >> 16; /* un-extend tmp (divide by 2^16) */ - - DEBUGPWM("Writing %u to Update register\n", tmp); - AT91F_PWMC_UpdateChannel(AT91C_BASE_PWMC, channel, tmp); -} - -static int pwm_usb_in(struct req_ctx *rctx) -{ - struct openpcd_hdr *poh = (struct openpcd_hdr *) &rctx->rx.data[0]; - /* struct openpcd_hdr *pih = (struct openpcd_hdr *) &rctx->tx.data[0]; */ - u_int32_t *freq; - - switch (poh->cmd) { - case OPENPCD_CMD_PWM_ENABLE: - if (poh->val) - pwm_start(0); - else - pwm_stop(0); - break; - case OPENPCD_CMD_PWM_DUTY_SET: - pwm_duty_set_percent(0, poh->val); - break; - case OPENPCD_CMD_PWM_DUTY_GET: - goto respond; - break; - case OPENPCD_CMD_PWM_FREQ_SET: - if (rctx->rx.tot_len < sizeof(*poh)+4) - break; - freq = (unsigned char *) poh + sizeof(*poh); - pwm_freq_set(0, *freq); - break; - case OPENPCD_CMD_PWM_FREQ_GET: - goto respond; - break; - default: - break; - } - - req_ctx_put(rctx); - return 0; -respond: - req_ctx_set_state(rctx, RCTX_STATE_UDP_EP2_PENDING); - udp_refill_ep(2, rctx); - return 1; -} - -void pwm_init(void) -{ - /* IMPORTANT: Disable PA17 (SSC TD) output */ - AT91F_PIO_CfgInput(AT91C_BASE_PIOA, AT91C_PIO_PA17); - - /* Set PA23 to Peripheral A (PWM0) */ - AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA, 0, OPENPCD_PIO_MFIN_PWM); - - /* Enable Clock for PWM controller */ - AT91F_PWMC_CfgPMC(); - - usb_hdlr_register(&pwm_usb_in, OPENPCD_CMD_CLS_PWM); -} - -void pwm_fini(void) -{ - usb_hdlr_unregister(OPENPCD_CMD_CLS_PWM); - AT91F_PMC_DisablePeriphClock(AT91C_BASE_PMC, (1 << AT91C_ID_PWMC)); -} |