Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 459 insertions, 0 deletions

diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c
new file mode 100644
index 0000000000..b0f24cf3e8
--- /dev/null
+++ b/drivers/counter/ti-eqep.c
@@ -0,0 +1,459 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 David Lechner <david@lechnology.com>
+ *
+ * Counter driver for Texas Instruments Enhanced Quadrature Encoder Pulse (eQEP)
+ */
+
+#include <linux/bitops.h>
+#include <linux/counter.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/types.h>
+
+/* 32-bit registers */
+#define QPOSCNT		0x0
+#define QPOSINIT	0x4
+#define QPOSMAX		0x8
+#define QPOSCMP		0xc
+#define QPOSILAT	0x10
+#define QPOSSLAT	0x14
+#define QPOSLAT		0x18
+#define QUTMR		0x1c
+#define QUPRD		0x20
+
+/* 16-bit registers */
+#define QWDTMR		0x0	/* 0x24 */
+#define QWDPRD		0x2	/* 0x26 */
+#define QDECCTL		0x4	/* 0x28 */
+#define QEPCTL		0x6	/* 0x2a */
+#define QCAPCTL		0x8	/* 0x2c */
+#define QPOSCTL		0xa	/* 0x2e */
+#define QEINT		0xc	/* 0x30 */
+#define QFLG		0xe	/* 0x32 */
+#define QCLR		0x10	/* 0x34 */
+#define QFRC		0x12	/* 0x36 */
+#define QEPSTS		0x14	/* 0x38 */
+#define QCTMR		0x16	/* 0x3a */
+#define QCPRD		0x18	/* 0x3c */
+#define QCTMRLAT	0x1a	/* 0x3e */
+#define QCPRDLAT	0x1c	/* 0x40 */
+
+#define QDECCTL_QSRC_SHIFT	14
+#define QDECCTL_QSRC		GENMASK(15, 14)
+#define QDECCTL_SOEN		BIT(13)
+#define QDECCTL_SPSEL		BIT(12)
+#define QDECCTL_XCR		BIT(11)
+#define QDECCTL_SWAP		BIT(10)
+#define QDECCTL_IGATE		BIT(9)
+#define QDECCTL_QAP		BIT(8)
+#define QDECCTL_QBP		BIT(7)
+#define QDECCTL_QIP		BIT(6)
+#define QDECCTL_QSP		BIT(5)
+
+#define QEPCTL_FREE_SOFT	GENMASK(15, 14)
+#define QEPCTL_PCRM		GENMASK(13, 12)
+#define QEPCTL_SEI		GENMASK(11, 10)
+#define QEPCTL_IEI		GENMASK(9, 8)
+#define QEPCTL_SWI		BIT(7)
+#define QEPCTL_SEL		BIT(6)
+#define QEPCTL_IEL		GENMASK(5, 4)
+#define QEPCTL_PHEN		BIT(3)
+#define QEPCTL_QCLM		BIT(2)
+#define QEPCTL_UTE		BIT(1)
+#define QEPCTL_WDE		BIT(0)
+
+/* EQEP Inputs */
+enum {
+	TI_EQEP_SIGNAL_QEPA,	/* QEPA/XCLK */
+	TI_EQEP_SIGNAL_QEPB,	/* QEPB/XDIR */
+};
+
+/* Position Counter Input Modes */
+enum ti_eqep_count_func {
+	TI_EQEP_COUNT_FUNC_QUAD_COUNT,
+	TI_EQEP_COUNT_FUNC_DIR_COUNT,
+	TI_EQEP_COUNT_FUNC_UP_COUNT,
+	TI_EQEP_COUNT_FUNC_DOWN_COUNT,
+};
+
+struct ti_eqep_cnt {
+	struct counter_device counter;
+	struct regmap *regmap32;
+	struct regmap *regmap16;
+};
+
+static struct ti_eqep_cnt *ti_eqep_count_from_counter(struct counter_device *counter)
+{
+	return counter_priv(counter);
+}
+
+static int ti_eqep_count_read(struct counter_device *counter,
+			      struct counter_count *count, u64 *val)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	u32 cnt;
+
+	regmap_read(priv->regmap32, QPOSCNT, &cnt);
+	*val = cnt;
+
+	return 0;
+}
+
+static int ti_eqep_count_write(struct counter_device *counter,
+			       struct counter_count *count, u64 val)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	u32 max;
+
+	regmap_read(priv->regmap32, QPOSMAX, &max);
+	if (val > max)
+		return -EINVAL;
+
+	return regmap_write(priv->regmap32, QPOSCNT, val);
+}
+
+static int ti_eqep_function_read(struct counter_device *counter,
+				 struct counter_count *count,
+				 enum counter_function *function)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	u32 qdecctl;
+
+	regmap_read(priv->regmap16, QDECCTL, &qdecctl);
+
+	switch ((qdecctl & QDECCTL_QSRC) >> QDECCTL_QSRC_SHIFT) {
+	case TI_EQEP_COUNT_FUNC_QUAD_COUNT:
+		*function = COUNTER_FUNCTION_QUADRATURE_X4;
+		break;
+	case TI_EQEP_COUNT_FUNC_DIR_COUNT:
+		*function = COUNTER_FUNCTION_PULSE_DIRECTION;
+		break;
+	case TI_EQEP_COUNT_FUNC_UP_COUNT:
+		*function = COUNTER_FUNCTION_INCREASE;
+		break;
+	case TI_EQEP_COUNT_FUNC_DOWN_COUNT:
+		*function = COUNTER_FUNCTION_DECREASE;
+		break;
+	}
+
+	return 0;
+}
+
+static int ti_eqep_function_write(struct counter_device *counter,
+				  struct counter_count *count,
+				  enum counter_function function)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	enum ti_eqep_count_func qsrc;
+
+	switch (function) {
+	case COUNTER_FUNCTION_QUADRATURE_X4:
+		qsrc = TI_EQEP_COUNT_FUNC_QUAD_COUNT;
+		break;
+	case COUNTER_FUNCTION_PULSE_DIRECTION:
+		qsrc = TI_EQEP_COUNT_FUNC_DIR_COUNT;
+		break;
+	case COUNTER_FUNCTION_INCREASE:
+		qsrc = TI_EQEP_COUNT_FUNC_UP_COUNT;
+		break;
+	case COUNTER_FUNCTION_DECREASE:
+		qsrc = TI_EQEP_COUNT_FUNC_DOWN_COUNT;
+		break;
+	default:
+		/* should never reach this path */
+		return -EINVAL;
+	}
+
+	return regmap_write_bits(priv->regmap16, QDECCTL, QDECCTL_QSRC,
+				 qsrc << QDECCTL_QSRC_SHIFT);
+}
+
+static int ti_eqep_action_read(struct counter_device *counter,
+			       struct counter_count *count,
+			       struct counter_synapse *synapse,
+			       enum counter_synapse_action *action)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	enum counter_function function;
+	u32 qdecctl;
+	int err;
+
+	err = ti_eqep_function_read(counter, count, &function);
+	if (err)
+		return err;
+
+	switch (function) {
+	case COUNTER_FUNCTION_QUADRATURE_X4:
+		/* In quadrature mode, the rising and falling edge of both
+		 * QEPA and QEPB trigger QCLK.
+		 */
+		*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+		return 0;
+	case COUNTER_FUNCTION_PULSE_DIRECTION:
+		/* In direction-count mode only rising edge of QEPA is counted
+		 * and QEPB gives direction.
+		 */
+		switch (synapse->signal->id) {
+		case TI_EQEP_SIGNAL_QEPA:
+			*action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
+			return 0;
+		case TI_EQEP_SIGNAL_QEPB:
+			*action = COUNTER_SYNAPSE_ACTION_NONE;
+			return 0;
+		default:
+			/* should never reach this path */
+			return -EINVAL;
+		}
+	case COUNTER_FUNCTION_INCREASE:
+	case COUNTER_FUNCTION_DECREASE:
+		/* In up/down-count modes only QEPA is counted and QEPB is not
+		 * used.
+		 */
+		switch (synapse->signal->id) {
+		case TI_EQEP_SIGNAL_QEPA:
+			err = regmap_read(priv->regmap16, QDECCTL, &qdecctl);
+			if (err)
+				return err;
+
+			if (qdecctl & QDECCTL_XCR)
+				*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+			else
+				*action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
+			return 0;
+		case TI_EQEP_SIGNAL_QEPB:
+			*action = COUNTER_SYNAPSE_ACTION_NONE;
+			return 0;
+		default:
+			/* should never reach this path */
+			return -EINVAL;
+		}
+	default:
+		/* should never reach this path */
+		return -EINVAL;
+	}
+}
+
+static const struct counter_ops ti_eqep_counter_ops = {
+	.count_read	= ti_eqep_count_read,
+	.count_write	= ti_eqep_count_write,
+	.function_read	= ti_eqep_function_read,
+	.function_write	= ti_eqep_function_write,
+	.action_read	= ti_eqep_action_read,
+};
+
+static int ti_eqep_position_ceiling_read(struct counter_device *counter,
+					 struct counter_count *count,
+					 u64 *ceiling)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	u32 qposmax;
+
+	regmap_read(priv->regmap32, QPOSMAX, &qposmax);
+
+	*ceiling = qposmax;
+
+	return 0;
+}
+
+static int ti_eqep_position_ceiling_write(struct counter_device *counter,
+					  struct counter_count *count,
+					  u64 ceiling)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+
+	if (ceiling != (u32)ceiling)
+		return -ERANGE;
+
+	regmap_write(priv->regmap32, QPOSMAX, ceiling);
+
+	return 0;
+}
+
+static int ti_eqep_position_enable_read(struct counter_device *counter,
+					struct counter_count *count, u8 *enable)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+	u32 qepctl;
+
+	regmap_read(priv->regmap16, QEPCTL, &qepctl);
+
+	*enable = !!(qepctl & QEPCTL_PHEN);
+
+	return 0;
+}
+
+static int ti_eqep_position_enable_write(struct counter_device *counter,
+					 struct counter_count *count, u8 enable)
+{
+	struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
+
+	regmap_write_bits(priv->regmap16, QEPCTL, QEPCTL_PHEN, enable ? -1 : 0);
+
+	return 0;
+}
+
+static struct counter_comp ti_eqep_position_ext[] = {
+	COUNTER_COMP_CEILING(ti_eqep_position_ceiling_read,
+			     ti_eqep_position_ceiling_write),
+	COUNTER_COMP_ENABLE(ti_eqep_position_enable_read,
+			    ti_eqep_position_enable_write),
+};
+
+static struct counter_signal ti_eqep_signals[] = {
+	[TI_EQEP_SIGNAL_QEPA] = {
+		.id = TI_EQEP_SIGNAL_QEPA,
+		.name = "QEPA"
+	},
+	[TI_EQEP_SIGNAL_QEPB] = {
+		.id = TI_EQEP_SIGNAL_QEPB,
+		.name = "QEPB"
+	},
+};
+
+static const enum counter_function ti_eqep_position_functions[] = {
+	COUNTER_FUNCTION_QUADRATURE_X4,
+	COUNTER_FUNCTION_PULSE_DIRECTION,
+	COUNTER_FUNCTION_INCREASE,
+	COUNTER_FUNCTION_DECREASE,
+};
+
+static const enum counter_synapse_action ti_eqep_position_synapse_actions[] = {
+	COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
+	COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+	COUNTER_SYNAPSE_ACTION_NONE,
+};
+
+static struct counter_synapse ti_eqep_position_synapses[] = {
+	{
+		.actions_list	= ti_eqep_position_synapse_actions,
+		.num_actions	= ARRAY_SIZE(ti_eqep_position_synapse_actions),
+		.signal		= &ti_eqep_signals[TI_EQEP_SIGNAL_QEPA],
+	},
+	{
+		.actions_list	= ti_eqep_position_synapse_actions,
+		.num_actions	= ARRAY_SIZE(ti_eqep_position_synapse_actions),
+		.signal		= &ti_eqep_signals[TI_EQEP_SIGNAL_QEPB],
+	},
+};
+
+static struct counter_count ti_eqep_counts[] = {
+	{
+		.id		= 0,
+		.name		= "QPOSCNT",
+		.functions_list	= ti_eqep_position_functions,
+		.num_functions	= ARRAY_SIZE(ti_eqep_position_functions),
+		.synapses	= ti_eqep_position_synapses,
+		.num_synapses	= ARRAY_SIZE(ti_eqep_position_synapses),
+		.ext		= ti_eqep_position_ext,
+		.num_ext	= ARRAY_SIZE(ti_eqep_position_ext),
+	},
+};
+
+static const struct regmap_config ti_eqep_regmap32_config = {
+	.name = "32-bit",
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = QUPRD,
+};
+
+static const struct regmap_config ti_eqep_regmap16_config = {
+	.name = "16-bit",
+	.reg_bits = 16,
+	.val_bits = 16,
+	.reg_stride = 2,
+	.max_register = QCPRDLAT,
+};
+
+static int ti_eqep_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct counter_device *counter;
+	struct ti_eqep_cnt *priv;
+	void __iomem *base;
+	int err;
+
+	counter = devm_counter_alloc(dev, sizeof(*priv));
+	if (!counter)
+		return -ENOMEM;
+	priv = counter_priv(counter);
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	priv->regmap32 = devm_regmap_init_mmio(dev, base,
+					       &ti_eqep_regmap32_config);
+	if (IS_ERR(priv->regmap32))
+		return PTR_ERR(priv->regmap32);
+
+	priv->regmap16 = devm_regmap_init_mmio(dev, base + 0x24,
+					       &ti_eqep_regmap16_config);
+	if (IS_ERR(priv->regmap16))
+		return PTR_ERR(priv->regmap16);
+
+	counter->name = dev_name(dev);
+	counter->parent = dev;
+	counter->ops = &ti_eqep_counter_ops;
+	counter->counts = ti_eqep_counts;
+	counter->num_counts = ARRAY_SIZE(ti_eqep_counts);
+	counter->signals = ti_eqep_signals;
+	counter->num_signals = ARRAY_SIZE(ti_eqep_signals);
+
+	platform_set_drvdata(pdev, counter);
+
+	/*
+	 * Need to make sure power is turned on. On AM33xx, this comes from the
+	 * parent PWMSS bus driver. On AM17xx, this comes from the PSC power
+	 * domain.
+	 */
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+
+	err = counter_add(counter);
+	if (err < 0) {
+		pm_runtime_put_sync(dev);
+		pm_runtime_disable(dev);
+		return err;
+	}
+
+	return 0;
+}
+
+static int ti_eqep_remove(struct platform_device *pdev)
+{
+	struct counter_device *counter = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+
+	counter_unregister(counter);
+	pm_runtime_put_sync(dev);
+	pm_runtime_disable(dev);
+
+	return 0;
+}
+
+static const struct of_device_id ti_eqep_of_match[] = {
+	{ .compatible = "ti,am3352-eqep", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, ti_eqep_of_match);
+
+static struct platform_driver ti_eqep_driver = {
+	.probe = ti_eqep_probe,
+	.remove = ti_eqep_remove,
+	.driver = {
+		.name = "ti-eqep-cnt",
+		.of_match_table = ti_eqep_of_match,
+	},
+};
+module_platform_driver(ti_eqep_driver);
+
+MODULE_AUTHOR("David Lechner <david@lechnology.com>");
+MODULE_DESCRIPTION("TI eQEP counter driver");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(COUNTER);