1 files changed, 350 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c
new file mode 100644
index 00000000000..04a329a377e
--- /dev/null
+++ b/drivers/base/regmap/regmap-mmio.c
@@ -0,0 +1,350 @@
+/*
+ * Register map access API - MMIO support
+ *
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+struct regmap_mmio_context {
+	void __iomem *regs;
+	unsigned reg_bytes;
+	unsigned val_bytes;
+	unsigned pad_bytes;
+	struct clk *clk;
+};
+
+static inline void regmap_mmio_regsize_check(size_t reg_size)
+{
+	switch (reg_size) {
+	case 1:
+	case 2:
+	case 4:
+#ifdef CONFIG_64BIT
+	case 8:
+#endif
+		break;
+	default:
+		BUG();
+	}
+}
+
+static int regmap_mmio_regbits_check(size_t reg_bits)
+{
+	switch (reg_bits) {
+	case 8:
+	case 16:
+	case 32:
+#ifdef CONFIG_64BIT
+	case 64:
+#endif
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static inline void regmap_mmio_count_check(size_t count, u32 offset)
+{
+	BUG_ON(count <= offset);
+}
+
+static inline unsigned int
+regmap_mmio_get_offset(const void *reg, size_t reg_size)
+{
+	switch (reg_size) {
+	case 1:
+		return *(u8 *)reg;
+	case 2:
+		return *(u16 *)reg;
+	case 4:
+		return *(u32 *)reg;
+#ifdef CONFIG_64BIT
+	case 8:
+		return *(u64 *)reg;
+#endif
+	default:
+		BUG();
+	}
+}
+
+static int regmap_mmio_gather_write(void *context,
+				    const void *reg, size_t reg_size,
+				    const void *val, size_t val_size)
+{
+	struct regmap_mmio_context *ctx = context;
+	unsigned int offset;
+	int ret;
+
+	regmap_mmio_regsize_check(reg_size);
+
+	if (!IS_ERR(ctx->clk)) {
+		ret = clk_enable(ctx->clk);
+		if (ret < 0)
+			return ret;
+	}
+
+	offset = regmap_mmio_get_offset(reg, reg_size);
+
+	while (val_size) {
+		switch (ctx->val_bytes) {
+		case 1:
+			writeb(*(u8 *)val, ctx->regs + offset);
+			break;
+		case 2:
+			writew(*(u16 *)val, ctx->regs + offset);
+			break;
+		case 4:
+			writel(*(u32 *)val, ctx->regs + offset);
+			break;
+#ifdef CONFIG_64BIT
+		case 8:
+			writeq(*(u64 *)val, ctx->regs + offset);
+			break;
+#endif
+		default:
+			/* Should be caught by regmap_mmio_check_config */
+			BUG();
+		}
+		val_size -= ctx->val_bytes;
+		val += ctx->val_bytes;
+		offset += ctx->val_bytes;
+	}
+
+	if (!IS_ERR(ctx->clk))
+		clk_disable(ctx->clk);
+
+	return 0;
+}
+
+static int regmap_mmio_write(void *context, const void *data, size_t count)
+{
+	struct regmap_mmio_context *ctx = context;
+	unsigned int offset = ctx->reg_bytes + ctx->pad_bytes;
+
+	regmap_mmio_count_check(count, offset);
+
+	return regmap_mmio_gather_write(context, data, ctx->reg_bytes,
+					data + offset, count - offset);
+}
+
+static int regmap_mmio_read(void *context,
+			    const void *reg, size_t reg_size,
+			    void *val, size_t val_size)
+{
+	struct regmap_mmio_context *ctx = context;
+	unsigned int offset;
+	int ret;
+
+	regmap_mmio_regsize_check(reg_size);
+
+	if (!IS_ERR(ctx->clk)) {
+		ret = clk_enable(ctx->clk);
+		if (ret < 0)
+			return ret;
+	}
+
+	offset = regmap_mmio_get_offset(reg, reg_size);
+
+	while (val_size) {
+		switch (ctx->val_bytes) {
+		case 1:
+			*(u8 *)val = readb(ctx->regs + offset);
+			break;
+		case 2:
+			*(u16 *)val = readw(ctx->regs + offset);
+			break;
+		case 4:
+			*(u32 *)val = readl(ctx->regs + offset);
+			break;
+#ifdef CONFIG_64BIT
+		case 8:
+			*(u64 *)val = readq(ctx->regs + offset);
+			break;
+#endif
+		default:
+			/* Should be caught by regmap_mmio_check_config */
+			BUG();
+		}
+		val_size -= ctx->val_bytes;
+		val += ctx->val_bytes;
+		offset += ctx->val_bytes;
+	}
+
+	if (!IS_ERR(ctx->clk))
+		clk_disable(ctx->clk);
+
+	return 0;
+}
+
+static void regmap_mmio_free_context(void *context)
+{
+	struct regmap_mmio_context *ctx = context;
+
+	if (!IS_ERR(ctx->clk)) {
+		clk_unprepare(ctx->clk);
+		clk_put(ctx->clk);
+	}
+	kfree(context);
+}
+
+static struct regmap_bus regmap_mmio = {
+	.fast_io = true,
+	.write = regmap_mmio_write,
+	.gather_write = regmap_mmio_gather_write,
+	.read = regmap_mmio_read,
+	.free_context = regmap_mmio_free_context,
+	.reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
+	.val_format_endian_default = REGMAP_ENDIAN_NATIVE,
+};
+
+static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev,
+					const char *clk_id,
+					void __iomem *regs,
+					const struct regmap_config *config)
+{
+	struct regmap_mmio_context *ctx;
+	int min_stride;
+	int ret;
+
+	ret = regmap_mmio_regbits_check(config->reg_bits);
+	if (ret)
+		return ERR_PTR(ret);
+
+	if (config->pad_bits)
+		return ERR_PTR(-EINVAL);
+
+	switch (config->val_bits) {
+	case 8:
+		/* The core treats 0 as 1 */
+		min_stride = 0;
+		break;
+	case 16:
+		min_stride = 2;
+		break;
+	case 32:
+		min_stride = 4;
+		break;
+#ifdef CONFIG_64BIT
+	case 64:
+		min_stride = 8;
+		break;
+#endif
+		break;
+	default:
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (config->reg_stride < min_stride)
+		return ERR_PTR(-EINVAL);
+
+	switch (config->reg_format_endian) {
+	case REGMAP_ENDIAN_DEFAULT:
+	case REGMAP_ENDIAN_NATIVE:
+		break;
+	default:
+		return ERR_PTR(-EINVAL);
+	}
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return ERR_PTR(-ENOMEM);
+
+	ctx->regs = regs;
+	ctx->val_bytes = config->val_bits / 8;
+	ctx->reg_bytes = config->reg_bits / 8;
+	ctx->pad_bytes = config->pad_bits / 8;
+	ctx->clk = ERR_PTR(-ENODEV);
+
+	if (clk_id == NULL)
+		return ctx;
+
+	ctx->clk = clk_get(dev, clk_id);
+	if (IS_ERR(ctx->clk)) {
+		ret = PTR_ERR(ctx->clk);
+		goto err_free;
+	}
+
+	ret = clk_prepare(ctx->clk);
+	if (ret < 0) {
+		clk_put(ctx->clk);
+		goto err_free;
+	}
+
+	return ctx;
+
+err_free:
+	kfree(ctx);
+
+	return ERR_PTR(ret);
+}
+
+/**
+ * regmap_init_mmio_clk(): Initialise register map with register clock
+ *
+ * @dev: Device that will be interacted with
+ * @clk_id: register clock consumer ID
+ * @regs: Pointer to memory-mapped IO region
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer to
+ * a struct regmap.
+ */
+struct regmap *regmap_init_mmio_clk(struct device *dev, const char *clk_id,
+				    void __iomem *regs,
+				    const struct regmap_config *config)
+{
+	struct regmap_mmio_context *ctx;
+
+	ctx = regmap_mmio_gen_context(dev, clk_id, regs, config);
+	if (IS_ERR(ctx))
+		return ERR_CAST(ctx);
+
+	return regmap_init(dev, &regmap_mmio, ctx, config);
+}
+EXPORT_SYMBOL_GPL(regmap_init_mmio_clk);
+
+/**
+ * devm_regmap_init_mmio_clk(): Initialise managed register map with clock
+ *
+ * @dev: Device that will be interacted with
+ * @clk_id: register clock consumer ID
+ * @regs: Pointer to memory-mapped IO region
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap.  The regmap will be automatically freed by the
+ * device management code.
+ */
+struct regmap *devm_regmap_init_mmio_clk(struct device *dev, const char *clk_id,
+					 void __iomem *regs,
+					 const struct regmap_config *config)
+{
+	struct regmap_mmio_context *ctx;
+
+	ctx = regmap_mmio_gen_context(dev, clk_id, regs, config);
+	if (IS_ERR(ctx))
+		return ERR_CAST(ctx);
+
+	return devm_regmap_init(dev, &regmap_mmio, ctx, config);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_init_mmio_clk);
+
+MODULE_LICENSE("GPL v2");