After setting alarm or time the driver is waiting for UDR register to be
cleared indicating that registers data have been transferred.
Limit the endless loop to only 5 retries.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Mark Brown <broonie@linaro.org>
Acked-by: Sangbeom Kim <sbkim73@samsung.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
#include <linux/mfd/samsung/irq.h>
#include <linux/mfd/samsung/rtc.h>
#include <linux/mfd/samsung/irq.h>
#include <linux/mfd/samsung/rtc.h>
+/*
+ * Maximum number of retries for checking changes in UDR field
+ * of SEC_RTC_UDR_CON register (to limit possible endless loop).
+ *
+ * After writing to RTC registers (setting time or alarm) read the UDR field
+ * in SEC_RTC_UDR_CON register. UDR is auto-cleared when data have
+ * been transferred.
+ */
+#define UDR_READ_RETRY_CNT 5
+
struct s5m_rtc_info {
struct device *dev;
struct sec_pmic_dev *s5m87xx;
struct s5m_rtc_info {
struct device *dev;
struct sec_pmic_dev *s5m87xx;
+/*
+ * Read RTC_UDR_CON register and wait till UDR field is cleared.
+ * This indicates that time/alarm update ended.
+ */
+static inline int s5m8767_wait_for_udr_update(struct s5m_rtc_info *info)
+{
+ int ret, retry = UDR_READ_RETRY_CNT;
+ unsigned int data;
+
+ do {
+ ret = regmap_read(info->regmap, SEC_RTC_UDR_CON, &data);
+ } while (--retry && (data & RTC_UDR_MASK) && !ret);
+
+ if (!retry)
+ dev_err(info->dev, "waiting for UDR update, reached max number of retries\n");
+
+ return ret;
+}
+
static inline int s5m8767_rtc_set_time_reg(struct s5m_rtc_info *info)
{
int ret;
static inline int s5m8767_rtc_set_time_reg(struct s5m_rtc_info *info)
{
int ret;
- do {
- ret = regmap_read(info->regmap, SEC_RTC_UDR_CON, &data);
- } while ((data & RTC_UDR_MASK) && !ret);
+ ret = s5m8767_wait_for_udr_update(info);
- do {
- ret = regmap_read(info->regmap, SEC_RTC_UDR_CON, &data);
- } while ((data & RTC_UDR_MASK) && !ret);
+ ret = s5m8767_wait_for_udr_update(info);