1 files changed, 574 insertions, 0 deletions

diff --git a/drivers/base/regmap/regmap-fmt.c b/drivers/base/regmap/regmap-fmt.c
new file mode 100644
index 0000000000..e7f6a8da80
--- /dev/null
+++ b/drivers/base/regmap/regmap-fmt.c
@@ -0,0 +1,574 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Formatted register map access API
+ *
+ * Copyright 2022 Ahmad Fatoum <a.fatoum@pengutronix.de>
+ *
+ * based on Kernel code:
+ *
+ * Copyright 2011 Wolfson Microelectronics plc
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ */
+
+#include <common.h>
+#include <linux/regmap.h>
+#include <linux/log2.h>
+#include <asm/unaligned.h>
+
+#include "internal.h"
+
+static void regmap_format_12_20_write(struct regmap *map,
+				     unsigned int reg, unsigned int val)
+{
+	u8 *out = map->work_buf;
+
+	out[0] = reg >> 4;
+	out[1] = (reg << 4) | (val >> 16);
+	out[2] = val >> 8;
+	out[3] = val;
+}
+
+
+static void regmap_format_2_6_write(struct regmap *map,
+				     unsigned int reg, unsigned int val)
+{
+	u8 *out = map->work_buf;
+
+	*out = (reg << 6) | val;
+}
+
+static void regmap_format_4_12_write(struct regmap *map,
+				     unsigned int reg, unsigned int val)
+{
+	__be16 *out = map->work_buf;
+	*out = cpu_to_be16((reg << 12) | val);
+}
+
+static void regmap_format_7_9_write(struct regmap *map,
+				    unsigned int reg, unsigned int val)
+{
+	__be16 *out = map->work_buf;
+	*out = cpu_to_be16((reg << 9) | val);
+}
+
+static void regmap_format_7_17_write(struct regmap *map,
+				    unsigned int reg, unsigned int val)
+{
+	u8 *out = map->work_buf;
+
+	out[2] = val;
+	out[1] = val >> 8;
+	out[0] = (val >> 16) | (reg << 1);
+}
+
+static void regmap_format_10_14_write(struct regmap *map,
+				    unsigned int reg, unsigned int val)
+{
+	u8 *out = map->work_buf;
+
+	out[2] = val;
+	out[1] = (val >> 8) | (reg << 6);
+	out[0] = reg >> 2;
+}
+
+static void regmap_format_8(void *buf, unsigned int val, unsigned int shift)
+{
+	u8 *b = buf;
+
+	b[0] = val << shift;
+}
+
+static void regmap_format_16_be(void *buf, unsigned int val, unsigned int shift)
+{
+	put_unaligned_be16(val << shift, buf);
+}
+
+static void regmap_format_16_le(void *buf, unsigned int val, unsigned int shift)
+{
+	put_unaligned_le16(val << shift, buf);
+}
+
+static void regmap_format_16_native(void *buf, unsigned int val,
+				    unsigned int shift)
+{
+	u16 v = val << shift;
+
+	memcpy(buf, &v, sizeof(v));
+}
+
+static void regmap_format_24(void *buf, unsigned int val, unsigned int shift)
+{
+	u8 *b = buf;
+
+	val <<= shift;
+
+	b[0] = val >> 16;
+	b[1] = val >> 8;
+	b[2] = val;
+}
+
+static void regmap_format_32_be(void *buf, unsigned int val, unsigned int shift)
+{
+	put_unaligned_be32(val << shift, buf);
+}
+
+static void regmap_format_32_le(void *buf, unsigned int val, unsigned int shift)
+{
+	put_unaligned_le32(val << shift, buf);
+}
+
+static void regmap_format_32_native(void *buf, unsigned int val,
+				    unsigned int shift)
+{
+	u32 v = val << shift;
+
+	memcpy(buf, &v, sizeof(v));
+}
+
+#ifdef CONFIG_64BIT
+static void regmap_format_64_be(void *buf, unsigned int val, unsigned int shift)
+{
+	put_unaligned_be64((u64) val << shift, buf);
+}
+
+static void regmap_format_64_le(void *buf, unsigned int val, unsigned int shift)
+{
+	put_unaligned_le64((u64) val << shift, buf);
+}
+
+static void regmap_format_64_native(void *buf, unsigned int val,
+				    unsigned int shift)
+{
+	u64 v = (u64) val << shift;
+
+	memcpy(buf, &v, sizeof(v));
+}
+#endif
+
+static unsigned int regmap_parse_8(const void *buf)
+{
+	const u8 *b = buf;
+
+	return b[0];
+}
+
+static unsigned int regmap_parse_16_be(const void *buf)
+{
+	return get_unaligned_be16(buf);
+}
+
+static unsigned int regmap_parse_16_le(const void *buf)
+{
+	return get_unaligned_le16(buf);
+}
+
+static unsigned int regmap_parse_16_native(const void *buf)
+{
+	u16 v;
+
+	memcpy(&v, buf, sizeof(v));
+	return v;
+}
+
+static unsigned int regmap_parse_24(const void *buf)
+{
+	const u8 *b = buf;
+	unsigned int ret = b[2];
+	ret |= ((unsigned int)b[1]) << 8;
+	ret |= ((unsigned int)b[0]) << 16;
+
+	return ret;
+}
+
+static unsigned int regmap_parse_32_be(const void *buf)
+{
+	return get_unaligned_be32(buf);
+}
+
+static unsigned int regmap_parse_32_le(const void *buf)
+{
+	return get_unaligned_le32(buf);
+}
+
+static unsigned int regmap_parse_32_native(const void *buf)
+{
+	u32 v;
+
+	memcpy(&v, buf, sizeof(v));
+	return v;
+}
+
+#ifdef CONFIG_64BIT
+static unsigned int regmap_parse_64_be(const void *buf)
+{
+	return get_unaligned_be64(buf);
+}
+
+static unsigned int regmap_parse_64_le(const void *buf)
+{
+	return get_unaligned_le64(buf);
+}
+
+static unsigned int regmap_parse_64_native(const void *buf)
+{
+	u64 v;
+
+	memcpy(&v, buf, sizeof(v));
+	return v;
+}
+#endif
+
+
+static enum regmap_endian regmap_get_reg_endian(const struct regmap_bus *bus,
+					const struct regmap_config *config)
+{
+	enum regmap_endian endian;
+
+	/* Retrieve the endianness specification from the regmap config */
+	endian = config->reg_format_endian;
+
+	/* If the regmap config specified a non-default value, use that */
+	if (endian != REGMAP_ENDIAN_DEFAULT)
+		return endian;
+
+	/* Retrieve the endianness specification from the bus config */
+	if (bus && bus->reg_format_endian_default)
+		endian = bus->reg_format_endian_default;
+
+	/* If the bus specified a non-default value, use that */
+	if (endian != REGMAP_ENDIAN_DEFAULT)
+		return endian;
+
+	/* Use this if no other value was found */
+	return REGMAP_ENDIAN_BIG;
+}
+
+static void regmap_set_work_buf_flag_mask(struct regmap *map, int max_bytes,
+					  unsigned long mask)
+{
+	u8 *buf;
+	int i;
+
+	if (!mask || !map->work_buf)
+		return;
+
+	buf = map->work_buf;
+
+	for (i = 0; i < max_bytes; i++)
+		buf[i] |= (mask >> (8 * i)) & 0xff;
+}
+
+static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
+			    unsigned int val_len, bool noinc)
+{
+	const struct regmap_bus *bus = map->bus;
+
+	if (!bus->read)
+		return -EINVAL;
+
+	map->format.format_reg(map->work_buf, reg, map->reg_shift);
+	regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
+				      map->read_flag_mask);
+
+	return bus->read(map->bus_context, map->work_buf,
+			 map->format.reg_bytes + map->format.pad_bytes,
+			 val, val_len);
+
+}
+
+static int _regmap_bus_read(void *context, unsigned int reg,
+			    unsigned int *val)
+{
+	int ret;
+	struct regmap *map = context;
+	void *work_val = map->work_buf + map->format.reg_bytes +
+		map->format.pad_bytes;
+
+	if (!map->format.parse_val)
+		return -EINVAL;
+
+	ret = _regmap_raw_read(map, reg, work_val, map->format.val_bytes, false);
+	if (ret == 0)
+		*val = map->format.parse_val(work_val);
+
+	return ret;
+}
+
+static int _regmap_bus_formatted_write(void *context, unsigned int reg,
+				       unsigned int val)
+{
+	struct regmap *map = context;
+
+	map->format.format_write(map, reg, val);
+
+	return map->bus->write(map->bus_context, map->work_buf,
+			      map->format.buf_size);
+}
+
+static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
+				  const void *val, size_t val_len, bool noinc)
+{
+	void *work_val = map->work_buf + map->format.reg_bytes +
+		map->format.pad_bytes;
+
+	map->format.format_reg(map->work_buf, reg, map->reg_shift);
+	regmap_set_work_buf_flag_mask(map, map->format.reg_bytes,
+				      map->write_flag_mask);
+
+	/*
+	 * Essentially all I/O mechanisms will be faster with a single
+	 * buffer to write.  Since register syncs often generate raw
+	 * writes of single registers optimise that case.
+	 */
+	if (val != work_val && val_len == map->format.val_bytes) {
+		memcpy(work_val, val, map->format.val_bytes);
+		val = work_val;
+	}
+
+	/* If we're doing a single register write we can probably just
+	 * send the work_buf directly, otherwise try to do a gather
+	 * write.
+	 */
+	return map->bus->write(map->bus_context, map->work_buf,
+			       map->format.reg_bytes +
+			       map->format.pad_bytes +
+			       val_len);
+
+}
+
+static int _regmap_bus_raw_write(void *context, unsigned int reg,
+				 unsigned int val)
+{
+	struct regmap *map = context;
+
+	WARN_ON(!map->format.format_val);
+
+	map->format.format_val(map->work_buf + map->format.reg_bytes
+			       + map->format.pad_bytes, val, 0);
+	return _regmap_raw_write_impl(map, reg,
+				      map->work_buf +
+				      map->format.reg_bytes +
+				      map->format.pad_bytes,
+				      map->format.val_bytes,
+				      false);
+}
+
+int regmap_formatted_init(struct regmap *map, const struct regmap_config *config)
+{
+	enum regmap_endian reg_endian, val_endian;
+	const struct regmap_bus *bus = map->bus;
+
+	map->format.buf_size = DIV_ROUND_UP(config->reg_bits +
+			config->val_bits + config->pad_bits, 8);
+
+	map->work_buf = xzalloc(map->format.buf_size);
+
+	if (config->read_flag_mask || config->write_flag_mask) {
+		map->read_flag_mask = config->read_flag_mask;
+		map->write_flag_mask = config->write_flag_mask;
+	} else {
+		map->read_flag_mask = bus->read_flag_mask;
+	}
+
+	map->reg_read = _regmap_bus_read;
+
+	reg_endian = regmap_get_reg_endian(bus, config);
+	val_endian = regmap_get_val_endian(map->dev, bus, config);
+
+	switch (config->reg_bits + config->pad_bits % 8) {
+	case 2:
+		switch (config->val_bits) {
+		case 6:
+			map->format.format_write = regmap_format_2_6_write;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+	case 4:
+		switch (config->val_bits) {
+		case 12:
+			map->format.format_write = regmap_format_4_12_write;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+	case 7:
+		switch (config->val_bits) {
+		case 9:
+			map->format.format_write = regmap_format_7_9_write;
+			break;
+		case 17:
+			map->format.format_write = regmap_format_7_17_write;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+	case 10:
+		switch (config->val_bits) {
+		case 14:
+			map->format.format_write = regmap_format_10_14_write;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+	case 12:
+		switch (config->val_bits) {
+		case 20:
+			map->format.format_write = regmap_format_12_20_write;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+	case 8:
+		map->format.format_reg = regmap_format_8;
+		break;
+
+	case 16:
+		switch (reg_endian) {
+		case REGMAP_ENDIAN_BIG:
+			map->format.format_reg = regmap_format_16_be;
+			break;
+		case REGMAP_ENDIAN_LITTLE:
+			map->format.format_reg = regmap_format_16_le;
+			break;
+		case REGMAP_ENDIAN_NATIVE:
+			map->format.format_reg = regmap_format_16_native;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+	case 24:
+		if (reg_endian != REGMAP_ENDIAN_BIG)
+			return -EINVAL;
+		map->format.format_reg = regmap_format_24;
+		break;
+
+	case 32:
+		switch (reg_endian) {
+		case REGMAP_ENDIAN_BIG:
+			map->format.format_reg = regmap_format_32_be;
+			break;
+		case REGMAP_ENDIAN_LITTLE:
+			map->format.format_reg = regmap_format_32_le;
+			break;
+		case REGMAP_ENDIAN_NATIVE:
+			map->format.format_reg = regmap_format_32_native;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+
+#ifdef CONFIG_64BIT
+	case 64:
+		switch (reg_endian) {
+		case REGMAP_ENDIAN_BIG:
+			map->format.format_reg = regmap_format_64_be;
+			break;
+		case REGMAP_ENDIAN_LITTLE:
+			map->format.format_reg = regmap_format_64_le;
+			break;
+		case REGMAP_ENDIAN_NATIVE:
+			map->format.format_reg = regmap_format_64_native;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+#endif
+
+	default:
+		return -EINVAL;
+	}
+
+	switch (config->val_bits) {
+	case 8:
+		map->format.format_val = regmap_format_8;
+		map->format.parse_val = regmap_parse_8;
+		break;
+	case 16:
+		switch (val_endian) {
+		case REGMAP_ENDIAN_BIG:
+			map->format.format_val = regmap_format_16_be;
+			map->format.parse_val = regmap_parse_16_be;
+			break;
+		case REGMAP_ENDIAN_LITTLE:
+			map->format.format_val = regmap_format_16_le;
+			map->format.parse_val = regmap_parse_16_le;
+			break;
+		case REGMAP_ENDIAN_NATIVE:
+			map->format.format_val = regmap_format_16_native;
+			map->format.parse_val = regmap_parse_16_native;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case 24:
+		if (val_endian != REGMAP_ENDIAN_BIG)
+			return -EINVAL;
+		map->format.format_val = regmap_format_24;
+		map->format.parse_val = regmap_parse_24;
+		break;
+	case 32:
+		switch (val_endian) {
+		case REGMAP_ENDIAN_BIG:
+			map->format.format_val = regmap_format_32_be;
+			map->format.parse_val = regmap_parse_32_be;
+			break;
+		case REGMAP_ENDIAN_LITTLE:
+			map->format.format_val = regmap_format_32_le;
+			map->format.parse_val = regmap_parse_32_le;
+			break;
+		case REGMAP_ENDIAN_NATIVE:
+			map->format.format_val = regmap_format_32_native;
+			map->format.parse_val = regmap_parse_32_native;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+#ifdef CONFIG_64BIT
+	case 64:
+		switch (val_endian) {
+		case REGMAP_ENDIAN_BIG:
+			map->format.format_val = regmap_format_64_be;
+			map->format.parse_val = regmap_parse_64_be;
+			break;
+		case REGMAP_ENDIAN_LITTLE:
+			map->format.format_val = regmap_format_64_le;
+			map->format.parse_val = regmap_parse_64_le;
+			break;
+		case REGMAP_ENDIAN_NATIVE:
+			map->format.format_val = regmap_format_64_native;
+			map->format.parse_val = regmap_parse_64_native;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+#endif
+	}
+
+	if (map->format.format_write)
+		map->reg_write = _regmap_bus_formatted_write;
+	else if (map->format.format_val)
+		map->reg_write = _regmap_bus_raw_write;
+	else
+		return -EOPNOTSUPP;
+
+	return 0;
+}