diff options
Diffstat (limited to 'drivers/counter/stm32-timer-cnt.c')
-rw-r--r-- | drivers/counter/stm32-timer-cnt.c | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c index ef2a974a2f10..75bc401fdd18 100644 --- a/drivers/counter/stm32-timer-cnt.c +++ b/drivers/counter/stm32-timer-cnt.c @@ -31,7 +31,7 @@ struct stm32_timer_cnt { struct counter_device counter; struct regmap *regmap; struct clk *clk; - u32 ceiling; + u32 max_arr; bool enabled; struct stm32_timer_regs bak; }; @@ -44,13 +44,14 @@ struct stm32_timer_cnt { * @STM32_COUNT_ENCODER_MODE_3: counts on both TI1FP1 and TI2FP2 edges */ enum stm32_count_function { - STM32_COUNT_SLAVE_MODE_DISABLED = -1, + STM32_COUNT_SLAVE_MODE_DISABLED, STM32_COUNT_ENCODER_MODE_1, STM32_COUNT_ENCODER_MODE_2, STM32_COUNT_ENCODER_MODE_3, }; static enum counter_count_function stm32_count_functions[] = { + [STM32_COUNT_SLAVE_MODE_DISABLED] = COUNTER_COUNT_FUNCTION_INCREASE, [STM32_COUNT_ENCODER_MODE_1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A, [STM32_COUNT_ENCODER_MODE_2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_B, [STM32_COUNT_ENCODER_MODE_3] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4, @@ -73,8 +74,10 @@ static int stm32_count_write(struct counter_device *counter, const unsigned long val) { struct stm32_timer_cnt *const priv = counter->priv; + u32 ceiling; - if (val > priv->ceiling) + regmap_read(priv->regmap, TIM_ARR, &ceiling); + if (val > ceiling) return -EINVAL; return regmap_write(priv->regmap, TIM_CNT, val); @@ -90,6 +93,9 @@ static int stm32_count_function_get(struct counter_device *counter, regmap_read(priv->regmap, TIM_SMCR, &smcr); switch (smcr & TIM_SMCR_SMS) { + case 0: + *function = STM32_COUNT_SLAVE_MODE_DISABLED; + return 0; case 1: *function = STM32_COUNT_ENCODER_MODE_1; return 0; @@ -99,9 +105,9 @@ static int stm32_count_function_get(struct counter_device *counter, case 3: *function = STM32_COUNT_ENCODER_MODE_3; return 0; + default: + return -EINVAL; } - - return -EINVAL; } static int stm32_count_function_set(struct counter_device *counter, @@ -112,6 +118,9 @@ static int stm32_count_function_set(struct counter_device *counter, u32 cr1, sms; switch (function) { + case STM32_COUNT_SLAVE_MODE_DISABLED: + sms = 0; + break; case STM32_COUNT_ENCODER_MODE_1: sms = 1; break; @@ -122,8 +131,7 @@ static int stm32_count_function_set(struct counter_device *counter, sms = 3; break; default: - sms = 0; - break; + return -EINVAL; } /* Store enable status */ @@ -131,10 +139,6 @@ static int stm32_count_function_set(struct counter_device *counter, regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); - /* TIMx_ARR register shouldn't be buffered (ARPE=0) */ - regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); - regmap_write(priv->regmap, TIM_ARR, priv->ceiling); - regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms); /* Make sure that registers are updated */ @@ -185,11 +189,13 @@ static ssize_t stm32_count_ceiling_write(struct counter_device *counter, if (ret) return ret; + if (ceiling > priv->max_arr) + return -ERANGE; + /* TIMx_ARR register shouldn't be buffered (ARPE=0) */ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); regmap_write(priv->regmap, TIM_ARR, ceiling); - priv->ceiling = ceiling; return len; } @@ -274,31 +280,36 @@ static int stm32_action_get(struct counter_device *counter, size_t function; int err; - /* Default action mode (e.g. STM32_COUNT_SLAVE_MODE_DISABLED) */ - *action = STM32_SYNAPSE_ACTION_NONE; - err = stm32_count_function_get(counter, count, &function); if (err) - return 0; + return err; switch (function) { + case STM32_COUNT_SLAVE_MODE_DISABLED: + /* counts on internal clock when CEN=1 */ + *action = STM32_SYNAPSE_ACTION_NONE; + return 0; case STM32_COUNT_ENCODER_MODE_1: /* counts up/down on TI1FP1 edge depending on TI2FP2 level */ if (synapse->signal->id == count->synapses[0].signal->id) *action = STM32_SYNAPSE_ACTION_BOTH_EDGES; - break; + else + *action = STM32_SYNAPSE_ACTION_NONE; + return 0; case STM32_COUNT_ENCODER_MODE_2: /* counts up/down on TI2FP2 edge depending on TI1FP1 level */ if (synapse->signal->id == count->synapses[1].signal->id) *action = STM32_SYNAPSE_ACTION_BOTH_EDGES; - break; + else + *action = STM32_SYNAPSE_ACTION_NONE; + return 0; case STM32_COUNT_ENCODER_MODE_3: /* counts up/down on both TI1FP1 and TI2FP2 edges */ *action = STM32_SYNAPSE_ACTION_BOTH_EDGES; - break; + return 0; + default: + return -EINVAL; } - - return 0; } static const struct counter_ops stm32_timer_cnt_ops = { @@ -359,7 +370,7 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) priv->regmap = ddata->regmap; priv->clk = ddata->clk; - priv->ceiling = ddata->max_arr; + priv->max_arr = ddata->max_arr; priv->counter.name = dev_name(dev); priv->counter.parent = dev; |