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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/counter/microchip-tcb-capture.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/counter/microchip-tcb-capture.c')
-rw-r--r-- | drivers/counter/microchip-tcb-capture.c | 407 |
1 files changed, 407 insertions, 0 deletions
diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c new file mode 100644 index 000000000..c7af13aca --- /dev/null +++ b/drivers/counter/microchip-tcb-capture.c @@ -0,0 +1,407 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 Microchip + * + * Author: Kamel Bouhara <kamel.bouhara@bootlin.com> + */ +#include <linux/clk.h> +#include <linux/counter.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <soc/at91/atmel_tcb.h> + +#define ATMEL_TC_CMR_MASK (ATMEL_TC_LDRA_RISING | ATMEL_TC_LDRB_FALLING | \ + ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_LDBDIS | \ + ATMEL_TC_LDBSTOP) + +#define ATMEL_TC_QDEN BIT(8) +#define ATMEL_TC_POSEN BIT(9) + +struct mchp_tc_data { + const struct atmel_tcb_config *tc_cfg; + struct regmap *regmap; + int qdec_mode; + int num_channels; + int channel[2]; +}; + +static const enum counter_function mchp_tc_count_functions[] = { + COUNTER_FUNCTION_INCREASE, + COUNTER_FUNCTION_QUADRATURE_X4, +}; + +static const enum counter_synapse_action mchp_tc_synapse_actions[] = { + COUNTER_SYNAPSE_ACTION_NONE, + COUNTER_SYNAPSE_ACTION_RISING_EDGE, + COUNTER_SYNAPSE_ACTION_FALLING_EDGE, + COUNTER_SYNAPSE_ACTION_BOTH_EDGES, +}; + +static struct counter_signal mchp_tc_count_signals[] = { + { + .id = 0, + .name = "Channel A", + }, + { + .id = 1, + .name = "Channel B", + } +}; + +static struct counter_synapse mchp_tc_count_synapses[] = { + { + .actions_list = mchp_tc_synapse_actions, + .num_actions = ARRAY_SIZE(mchp_tc_synapse_actions), + .signal = &mchp_tc_count_signals[0] + }, + { + .actions_list = mchp_tc_synapse_actions, + .num_actions = ARRAY_SIZE(mchp_tc_synapse_actions), + .signal = &mchp_tc_count_signals[1] + } +}; + +static int mchp_tc_count_function_read(struct counter_device *counter, + struct counter_count *count, + enum counter_function *function) +{ + struct mchp_tc_data *const priv = counter_priv(counter); + + if (priv->qdec_mode) + *function = COUNTER_FUNCTION_QUADRATURE_X4; + else + *function = COUNTER_FUNCTION_INCREASE; + + return 0; +} + +static int mchp_tc_count_function_write(struct counter_device *counter, + struct counter_count *count, + enum counter_function function) +{ + struct mchp_tc_data *const priv = counter_priv(counter); + u32 bmr, cmr; + + regmap_read(priv->regmap, ATMEL_TC_BMR, &bmr); + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr); + + /* Set capture mode */ + cmr &= ~ATMEL_TC_WAVE; + + switch (function) { + case COUNTER_FUNCTION_INCREASE: + priv->qdec_mode = 0; + /* Set highest rate based on whether soc has gclk or not */ + bmr &= ~(ATMEL_TC_QDEN | ATMEL_TC_POSEN); + if (!priv->tc_cfg->has_gclk) + cmr |= ATMEL_TC_TIMER_CLOCK2; + else + cmr |= ATMEL_TC_TIMER_CLOCK1; + /* Setup the period capture mode */ + cmr |= ATMEL_TC_CMR_MASK; + cmr &= ~(ATMEL_TC_ABETRG | ATMEL_TC_XC0); + break; + case COUNTER_FUNCTION_QUADRATURE_X4: + if (!priv->tc_cfg->has_qdec) + return -EINVAL; + /* In QDEC mode settings both channels 0 and 1 are required */ + if (priv->num_channels < 2 || priv->channel[0] != 0 || + priv->channel[1] != 1) { + pr_err("Invalid channels number or id for quadrature mode\n"); + return -EINVAL; + } + priv->qdec_mode = 1; + bmr |= ATMEL_TC_QDEN | ATMEL_TC_POSEN; + cmr |= ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_ABETRG | ATMEL_TC_XC0; + break; + default: + /* should never reach this path */ + return -EINVAL; + } + + regmap_write(priv->regmap, ATMEL_TC_BMR, bmr); + regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), cmr); + + /* Enable clock and trigger counter */ + regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CCR), + ATMEL_TC_CLKEN | ATMEL_TC_SWTRG); + + if (priv->qdec_mode) { + regmap_write(priv->regmap, + ATMEL_TC_REG(priv->channel[1], CMR), cmr); + regmap_write(priv->regmap, + ATMEL_TC_REG(priv->channel[1], CCR), + ATMEL_TC_CLKEN | ATMEL_TC_SWTRG); + } + + return 0; +} + +static int mchp_tc_count_signal_read(struct counter_device *counter, + struct counter_signal *signal, + enum counter_signal_level *lvl) +{ + struct mchp_tc_data *const priv = counter_priv(counter); + bool sigstatus; + u32 sr; + + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], SR), &sr); + + if (signal->id == 1) + sigstatus = (sr & ATMEL_TC_MTIOB); + else + sigstatus = (sr & ATMEL_TC_MTIOA); + + *lvl = sigstatus ? COUNTER_SIGNAL_LEVEL_HIGH : COUNTER_SIGNAL_LEVEL_LOW; + + return 0; +} + +static int mchp_tc_count_action_read(struct counter_device *counter, + struct counter_count *count, + struct counter_synapse *synapse, + enum counter_synapse_action *action) +{ + struct mchp_tc_data *const priv = counter_priv(counter); + u32 cmr; + + if (priv->qdec_mode) { + *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES; + return 0; + } + + /* Only TIOA signal is evaluated in non-QDEC mode */ + if (synapse->signal->id != 0) { + *action = COUNTER_SYNAPSE_ACTION_NONE; + return 0; + } + + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr); + + switch (cmr & ATMEL_TC_ETRGEDG) { + default: + *action = COUNTER_SYNAPSE_ACTION_NONE; + break; + case ATMEL_TC_ETRGEDG_RISING: + *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE; + break; + case ATMEL_TC_ETRGEDG_FALLING: + *action = COUNTER_SYNAPSE_ACTION_FALLING_EDGE; + break; + case ATMEL_TC_ETRGEDG_BOTH: + *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES; + break; + } + + return 0; +} + +static int mchp_tc_count_action_write(struct counter_device *counter, + struct counter_count *count, + struct counter_synapse *synapse, + enum counter_synapse_action action) +{ + struct mchp_tc_data *const priv = counter_priv(counter); + u32 edge = ATMEL_TC_ETRGEDG_NONE; + + /* QDEC mode is rising edge only; only TIOA handled in non-QDEC mode */ + if (priv->qdec_mode || synapse->signal->id != 0) + return -EINVAL; + + switch (action) { + case COUNTER_SYNAPSE_ACTION_NONE: + edge = ATMEL_TC_ETRGEDG_NONE; + break; + case COUNTER_SYNAPSE_ACTION_RISING_EDGE: + edge = ATMEL_TC_ETRGEDG_RISING; + break; + case COUNTER_SYNAPSE_ACTION_FALLING_EDGE: + edge = ATMEL_TC_ETRGEDG_FALLING; + break; + case COUNTER_SYNAPSE_ACTION_BOTH_EDGES: + edge = ATMEL_TC_ETRGEDG_BOTH; + break; + default: + /* should never reach this path */ + return -EINVAL; + } + + return regmap_write_bits(priv->regmap, + ATMEL_TC_REG(priv->channel[0], CMR), + ATMEL_TC_ETRGEDG, edge); +} + +static int mchp_tc_count_read(struct counter_device *counter, + struct counter_count *count, u64 *val) +{ + struct mchp_tc_data *const priv = counter_priv(counter); + u32 cnt; + + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CV), &cnt); + *val = cnt; + + return 0; +} + +static struct counter_count mchp_tc_counts[] = { + { + .id = 0, + .name = "Timer Counter", + .functions_list = mchp_tc_count_functions, + .num_functions = ARRAY_SIZE(mchp_tc_count_functions), + .synapses = mchp_tc_count_synapses, + .num_synapses = ARRAY_SIZE(mchp_tc_count_synapses), + }, +}; + +static const struct counter_ops mchp_tc_ops = { + .signal_read = mchp_tc_count_signal_read, + .count_read = mchp_tc_count_read, + .function_read = mchp_tc_count_function_read, + .function_write = mchp_tc_count_function_write, + .action_read = mchp_tc_count_action_read, + .action_write = mchp_tc_count_action_write +}; + +static const struct atmel_tcb_config tcb_rm9200_config = { + .counter_width = 16, +}; + +static const struct atmel_tcb_config tcb_sam9x5_config = { + .counter_width = 32, +}; + +static const struct atmel_tcb_config tcb_sama5d2_config = { + .counter_width = 32, + .has_gclk = true, + .has_qdec = true, +}; + +static const struct atmel_tcb_config tcb_sama5d3_config = { + .counter_width = 32, + .has_qdec = true, +}; + +static const struct of_device_id atmel_tc_of_match[] = { + { .compatible = "atmel,at91rm9200-tcb", .data = &tcb_rm9200_config, }, + { .compatible = "atmel,at91sam9x5-tcb", .data = &tcb_sam9x5_config, }, + { .compatible = "atmel,sama5d2-tcb", .data = &tcb_sama5d2_config, }, + { .compatible = "atmel,sama5d3-tcb", .data = &tcb_sama5d3_config, }, + { /* sentinel */ } +}; + +static void mchp_tc_clk_remove(void *ptr) +{ + clk_disable_unprepare((struct clk *)ptr); +} + +static int mchp_tc_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + const struct atmel_tcb_config *tcb_config; + const struct of_device_id *match; + struct counter_device *counter; + struct mchp_tc_data *priv; + char clk_name[7]; + struct regmap *regmap; + struct clk *clk[3]; + int channel; + int ret, i; + + counter = devm_counter_alloc(&pdev->dev, sizeof(*priv)); + if (!counter) + return -ENOMEM; + priv = counter_priv(counter); + + match = of_match_node(atmel_tc_of_match, np->parent); + tcb_config = match->data; + if (!tcb_config) { + dev_err(&pdev->dev, "No matching parent node found\n"); + return -ENODEV; + } + + regmap = syscon_node_to_regmap(np->parent); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + /* max. channels number is 2 when in QDEC mode */ + priv->num_channels = of_property_count_u32_elems(np, "reg"); + if (priv->num_channels < 0) { + dev_err(&pdev->dev, "Invalid or missing channel\n"); + return -EINVAL; + } + + /* Register channels and initialize clocks */ + for (i = 0; i < priv->num_channels; i++) { + ret = of_property_read_u32_index(np, "reg", i, &channel); + if (ret < 0 || channel > 2) + return -ENODEV; + + priv->channel[i] = channel; + + snprintf(clk_name, sizeof(clk_name), "t%d_clk", channel); + + clk[i] = of_clk_get_by_name(np->parent, clk_name); + if (IS_ERR(clk[i])) { + /* Fallback to t0_clk */ + clk[i] = of_clk_get_by_name(np->parent, "t0_clk"); + if (IS_ERR(clk[i])) + return PTR_ERR(clk[i]); + } + + ret = clk_prepare_enable(clk[i]); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&pdev->dev, + mchp_tc_clk_remove, + clk[i]); + if (ret) + return ret; + + dev_dbg(&pdev->dev, + "Initialized capture mode on channel %d\n", + channel); + } + + priv->tc_cfg = tcb_config; + priv->regmap = regmap; + counter->name = dev_name(&pdev->dev); + counter->parent = &pdev->dev; + counter->ops = &mchp_tc_ops; + counter->num_counts = ARRAY_SIZE(mchp_tc_counts); + counter->counts = mchp_tc_counts; + counter->num_signals = ARRAY_SIZE(mchp_tc_count_signals); + counter->signals = mchp_tc_count_signals; + + ret = devm_counter_add(&pdev->dev, counter); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, "Failed to add counter\n"); + + return 0; +} + +static const struct of_device_id mchp_tc_dt_ids[] = { + { .compatible = "microchip,tcb-capture", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, mchp_tc_dt_ids); + +static struct platform_driver mchp_tc_driver = { + .probe = mchp_tc_probe, + .driver = { + .name = "microchip-tcb-capture", + .of_match_table = mchp_tc_dt_ids, + }, +}; +module_platform_driver(mchp_tc_driver); + +MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@bootlin.com>"); +MODULE_DESCRIPTION("Microchip TCB Capture driver"); +MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS(COUNTER); |