summaryrefslogtreecommitdiffstats
path: root/drivers/counter/stm32-timer-cnt.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/counter/stm32-timer-cnt.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/counter/stm32-timer-cnt.c')
-rw-r--r--drivers/counter/stm32-timer-cnt.c420
1 files changed, 420 insertions, 0 deletions
diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c
new file mode 100644
index 000000000..9bf20a5d6
--- /dev/null
+++ b/drivers/counter/stm32-timer-cnt.c
@@ -0,0 +1,420 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * STM32 Timer Encoder and Counter driver
+ *
+ * Copyright (C) STMicroelectronics 2018
+ *
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com>
+ *
+ */
+#include <linux/counter.h>
+#include <linux/mfd/stm32-timers.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+#define TIM_CCMR_CCXS (BIT(8) | BIT(0))
+#define TIM_CCMR_MASK (TIM_CCMR_CC1S | TIM_CCMR_CC2S | \
+ TIM_CCMR_IC1F | TIM_CCMR_IC2F)
+#define TIM_CCER_MASK (TIM_CCER_CC1P | TIM_CCER_CC1NP | \
+ TIM_CCER_CC2P | TIM_CCER_CC2NP)
+
+struct stm32_timer_regs {
+ u32 cr1;
+ u32 cnt;
+ u32 smcr;
+ u32 arr;
+};
+
+struct stm32_timer_cnt {
+ struct regmap *regmap;
+ struct clk *clk;
+ u32 max_arr;
+ bool enabled;
+ struct stm32_timer_regs bak;
+};
+
+static const enum counter_function stm32_count_functions[] = {
+ COUNTER_FUNCTION_INCREASE,
+ COUNTER_FUNCTION_QUADRATURE_X2_A,
+ COUNTER_FUNCTION_QUADRATURE_X2_B,
+ COUNTER_FUNCTION_QUADRATURE_X4,
+};
+
+static int stm32_count_read(struct counter_device *counter,
+ struct counter_count *count, u64 *val)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 cnt;
+
+ regmap_read(priv->regmap, TIM_CNT, &cnt);
+ *val = cnt;
+
+ return 0;
+}
+
+static int stm32_count_write(struct counter_device *counter,
+ struct counter_count *count, const u64 val)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 ceiling;
+
+ regmap_read(priv->regmap, TIM_ARR, &ceiling);
+ if (val > ceiling)
+ return -EINVAL;
+
+ return regmap_write(priv->regmap, TIM_CNT, val);
+}
+
+static int stm32_count_function_read(struct counter_device *counter,
+ struct counter_count *count,
+ enum counter_function *function)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 smcr;
+
+ regmap_read(priv->regmap, TIM_SMCR, &smcr);
+
+ switch (smcr & TIM_SMCR_SMS) {
+ case TIM_SMCR_SMS_SLAVE_MODE_DISABLED:
+ *function = COUNTER_FUNCTION_INCREASE;
+ return 0;
+ case TIM_SMCR_SMS_ENCODER_MODE_1:
+ *function = COUNTER_FUNCTION_QUADRATURE_X2_A;
+ return 0;
+ case TIM_SMCR_SMS_ENCODER_MODE_2:
+ *function = COUNTER_FUNCTION_QUADRATURE_X2_B;
+ return 0;
+ case TIM_SMCR_SMS_ENCODER_MODE_3:
+ *function = COUNTER_FUNCTION_QUADRATURE_X4;
+ return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int stm32_count_function_write(struct counter_device *counter,
+ struct counter_count *count,
+ enum counter_function function)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 cr1, sms;
+
+ switch (function) {
+ case COUNTER_FUNCTION_INCREASE:
+ sms = TIM_SMCR_SMS_SLAVE_MODE_DISABLED;
+ break;
+ case COUNTER_FUNCTION_QUADRATURE_X2_A:
+ sms = TIM_SMCR_SMS_ENCODER_MODE_1;
+ break;
+ case COUNTER_FUNCTION_QUADRATURE_X2_B:
+ sms = TIM_SMCR_SMS_ENCODER_MODE_2;
+ break;
+ case COUNTER_FUNCTION_QUADRATURE_X4:
+ sms = TIM_SMCR_SMS_ENCODER_MODE_3;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* Store enable status */
+ regmap_read(priv->regmap, TIM_CR1, &cr1);
+
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
+
+ regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
+
+ /* Make sure that registers are updated */
+ regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
+
+ /* Restore the enable status */
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, cr1);
+
+ return 0;
+}
+
+static int stm32_count_direction_read(struct counter_device *counter,
+ struct counter_count *count,
+ enum counter_count_direction *direction)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 cr1;
+
+ regmap_read(priv->regmap, TIM_CR1, &cr1);
+ *direction = (cr1 & TIM_CR1_DIR) ? COUNTER_COUNT_DIRECTION_BACKWARD :
+ COUNTER_COUNT_DIRECTION_FORWARD;
+
+ return 0;
+}
+
+static int stm32_count_ceiling_read(struct counter_device *counter,
+ struct counter_count *count, u64 *ceiling)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 arr;
+
+ regmap_read(priv->regmap, TIM_ARR, &arr);
+
+ *ceiling = arr;
+
+ return 0;
+}
+
+static int stm32_count_ceiling_write(struct counter_device *counter,
+ struct counter_count *count, u64 ceiling)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+
+ 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);
+
+ return 0;
+}
+
+static int stm32_count_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 cr1;
+
+ regmap_read(priv->regmap, TIM_CR1, &cr1);
+
+ *enable = cr1 & TIM_CR1_CEN;
+
+ return 0;
+}
+
+static int stm32_count_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable)
+{
+ struct stm32_timer_cnt *const priv = counter_priv(counter);
+ u32 cr1;
+
+ if (enable) {
+ regmap_read(priv->regmap, TIM_CR1, &cr1);
+ if (!(cr1 & TIM_CR1_CEN))
+ clk_enable(priv->clk);
+
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN,
+ TIM_CR1_CEN);
+ } else {
+ regmap_read(priv->regmap, TIM_CR1, &cr1);
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
+ if (cr1 & TIM_CR1_CEN)
+ clk_disable(priv->clk);
+ }
+
+ /* Keep enabled state to properly handle low power states */
+ priv->enabled = enable;
+
+ return 0;
+}
+
+static struct counter_comp stm32_count_ext[] = {
+ COUNTER_COMP_DIRECTION(stm32_count_direction_read),
+ COUNTER_COMP_ENABLE(stm32_count_enable_read, stm32_count_enable_write),
+ COUNTER_COMP_CEILING(stm32_count_ceiling_read,
+ stm32_count_ceiling_write),
+};
+
+static const enum counter_synapse_action stm32_synapse_actions[] = {
+ COUNTER_SYNAPSE_ACTION_NONE,
+ COUNTER_SYNAPSE_ACTION_BOTH_EDGES
+};
+
+static int stm32_action_read(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse,
+ enum counter_synapse_action *action)
+{
+ enum counter_function function;
+ int err;
+
+ err = stm32_count_function_read(counter, count, &function);
+ if (err)
+ return err;
+
+ switch (function) {
+ case COUNTER_FUNCTION_INCREASE:
+ /* counts on internal clock when CEN=1 */
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
+ return 0;
+ case COUNTER_FUNCTION_QUADRATURE_X2_A:
+ /* counts up/down on TI1FP1 edge depending on TI2FP2 level */
+ if (synapse->signal->id == count->synapses[0].signal->id)
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+ else
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
+ return 0;
+ case COUNTER_FUNCTION_QUADRATURE_X2_B:
+ /* counts up/down on TI2FP2 edge depending on TI1FP1 level */
+ if (synapse->signal->id == count->synapses[1].signal->id)
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+ else
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
+ return 0;
+ case COUNTER_FUNCTION_QUADRATURE_X4:
+ /* counts up/down on both TI1FP1 and TI2FP2 edges */
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+ return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct counter_ops stm32_timer_cnt_ops = {
+ .count_read = stm32_count_read,
+ .count_write = stm32_count_write,
+ .function_read = stm32_count_function_read,
+ .function_write = stm32_count_function_write,
+ .action_read = stm32_action_read,
+};
+
+static struct counter_signal stm32_signals[] = {
+ {
+ .id = 0,
+ .name = "Channel 1 Quadrature A"
+ },
+ {
+ .id = 1,
+ .name = "Channel 1 Quadrature B"
+ }
+};
+
+static struct counter_synapse stm32_count_synapses[] = {
+ {
+ .actions_list = stm32_synapse_actions,
+ .num_actions = ARRAY_SIZE(stm32_synapse_actions),
+ .signal = &stm32_signals[0]
+ },
+ {
+ .actions_list = stm32_synapse_actions,
+ .num_actions = ARRAY_SIZE(stm32_synapse_actions),
+ .signal = &stm32_signals[1]
+ }
+};
+
+static struct counter_count stm32_counts = {
+ .id = 0,
+ .name = "Channel 1 Count",
+ .functions_list = stm32_count_functions,
+ .num_functions = ARRAY_SIZE(stm32_count_functions),
+ .synapses = stm32_count_synapses,
+ .num_synapses = ARRAY_SIZE(stm32_count_synapses),
+ .ext = stm32_count_ext,
+ .num_ext = ARRAY_SIZE(stm32_count_ext)
+};
+
+static int stm32_timer_cnt_probe(struct platform_device *pdev)
+{
+ struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent);
+ struct device *dev = &pdev->dev;
+ struct stm32_timer_cnt *priv;
+ struct counter_device *counter;
+ int ret;
+
+ if (IS_ERR_OR_NULL(ddata))
+ return -EINVAL;
+
+ counter = devm_counter_alloc(dev, sizeof(*priv));
+ if (!counter)
+ return -ENOMEM;
+
+ priv = counter_priv(counter);
+
+ priv->regmap = ddata->regmap;
+ priv->clk = ddata->clk;
+ priv->max_arr = ddata->max_arr;
+
+ counter->name = dev_name(dev);
+ counter->parent = dev;
+ counter->ops = &stm32_timer_cnt_ops;
+ counter->counts = &stm32_counts;
+ counter->num_counts = 1;
+ counter->signals = stm32_signals;
+ counter->num_signals = ARRAY_SIZE(stm32_signals);
+
+ platform_set_drvdata(pdev, priv);
+
+ /* Register Counter device */
+ ret = devm_counter_add(dev, counter);
+ if (ret < 0)
+ dev_err_probe(dev, ret, "Failed to add counter\n");
+
+ return ret;
+}
+
+static int __maybe_unused stm32_timer_cnt_suspend(struct device *dev)
+{
+ struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
+
+ /* Only take care of enabled counter: don't disturb other MFD child */
+ if (priv->enabled) {
+ /* Backup registers that may get lost in low power mode */
+ regmap_read(priv->regmap, TIM_SMCR, &priv->bak.smcr);
+ regmap_read(priv->regmap, TIM_ARR, &priv->bak.arr);
+ regmap_read(priv->regmap, TIM_CNT, &priv->bak.cnt);
+ regmap_read(priv->regmap, TIM_CR1, &priv->bak.cr1);
+
+ /* Disable the counter */
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
+ clk_disable(priv->clk);
+ }
+
+ return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int __maybe_unused stm32_timer_cnt_resume(struct device *dev)
+{
+ struct stm32_timer_cnt *priv = dev_get_drvdata(dev);
+ int ret;
+
+ ret = pinctrl_pm_select_default_state(dev);
+ if (ret)
+ return ret;
+
+ if (priv->enabled) {
+ clk_enable(priv->clk);
+
+ /* Restore registers that may have been lost */
+ regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr);
+ regmap_write(priv->regmap, TIM_ARR, priv->bak.arr);
+ regmap_write(priv->regmap, TIM_CNT, priv->bak.cnt);
+
+ /* Also re-enables the counter */
+ regmap_write(priv->regmap, TIM_CR1, priv->bak.cr1);
+ }
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_timer_cnt_pm_ops, stm32_timer_cnt_suspend,
+ stm32_timer_cnt_resume);
+
+static const struct of_device_id stm32_timer_cnt_of_match[] = {
+ { .compatible = "st,stm32-timer-counter", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stm32_timer_cnt_of_match);
+
+static struct platform_driver stm32_timer_cnt_driver = {
+ .probe = stm32_timer_cnt_probe,
+ .driver = {
+ .name = "stm32-timer-counter",
+ .of_match_table = stm32_timer_cnt_of_match,
+ .pm = &stm32_timer_cnt_pm_ops,
+ },
+};
+module_platform_driver(stm32_timer_cnt_driver);
+
+MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
+MODULE_ALIAS("platform:stm32-timer-counter");
+MODULE_DESCRIPTION("STMicroelectronics STM32 TIMER counter driver");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(COUNTER);