void (*clear_events)(struct stm32_rtc *rtc, unsigned int flags);
bool has_pclk;
bool need_dbp;
+ bool need_accuracy;
};
struct stm32_rtc {
static const struct stm32_rtc_data stm32_rtc_data = {
.has_pclk = false,
.need_dbp = true,
+ .need_accuracy = false,
.regs = {
.tr = 0x00,
.dr = 0x04,
static const struct stm32_rtc_data stm32h7_rtc_data = {
.has_pclk = true,
.need_dbp = true,
+ .need_accuracy = false,
.regs = {
.tr = 0x00,
.dr = 0x04,
static const struct stm32_rtc_data stm32mp1_data = {
.has_pclk = true,
.need_dbp = false,
+ .need_accuracy = true,
.regs = {
.tr = 0x00,
.dr = 0x04,
pred_a_max = STM32_RTC_PRER_PRED_A >> STM32_RTC_PRER_PRED_A_SHIFT;
pred_s_max = STM32_RTC_PRER_PRED_S >> STM32_RTC_PRER_PRED_S_SHIFT;
- for (pred_a = pred_a_max; pred_a + 1 > 0; pred_a--) {
- pred_s = (rate / (pred_a + 1)) - 1;
+ if (rate > (pred_a_max + 1) * (pred_s_max + 1)) {
+ dev_err(&pdev->dev, "rtc_ck rate is too high: %dHz\n", rate);
+ return -EINVAL;
+ }
+
+ if (rtc->data->need_accuracy) {
+ for (pred_a = 0; pred_a <= pred_a_max; pred_a++) {
+ pred_s = (rate / (pred_a + 1)) - 1;
- if (((pred_s + 1) * (pred_a + 1)) == rate)
- break;
+ if (pred_s <= pred_s_max && ((pred_s + 1) * (pred_a + 1)) == rate)
+ break;
+ }
+ } else {
+ for (pred_a = pred_a_max; pred_a + 1 > 0; pred_a--) {
+ pred_s = (rate / (pred_a + 1)) - 1;
+
+ if (((pred_s + 1) * (pred_a + 1)) == rate)
+ break;
+ }
}
/*