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-rw-r--r--kernel/drivers/base/regmap/regmap-spi.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/kernel/drivers/base/regmap/regmap-spi.c b/kernel/drivers/base/regmap/regmap-spi.c
new file mode 100644
index 000000000..53d1148e8
--- /dev/null
+++ b/kernel/drivers/base/regmap/regmap-spi.c
@@ -0,0 +1,149 @@
+/*
+ * Register map access API - SPI support
+ *
+ * Copyright 2011 Wolfson Microelectronics plc
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+#include <linux/module.h>
+
+#include "internal.h"
+
+struct regmap_async_spi {
+ struct regmap_async core;
+ struct spi_message m;
+ struct spi_transfer t[2];
+};
+
+static void regmap_spi_complete(void *data)
+{
+ struct regmap_async_spi *async = data;
+
+ regmap_async_complete_cb(&async->core, async->m.status);
+}
+
+static int regmap_spi_write(void *context, const void *data, size_t count)
+{
+ struct device *dev = context;
+ struct spi_device *spi = to_spi_device(dev);
+
+ return spi_write(spi, data, count);
+}
+
+static int regmap_spi_gather_write(void *context,
+ const void *reg, size_t reg_len,
+ const void *val, size_t val_len)
+{
+ struct device *dev = context;
+ struct spi_device *spi = to_spi_device(dev);
+ struct spi_message m;
+ struct spi_transfer t[2] = { { .tx_buf = reg, .len = reg_len, },
+ { .tx_buf = val, .len = val_len, }, };
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t[0], &m);
+ spi_message_add_tail(&t[1], &m);
+
+ return spi_sync(spi, &m);
+}
+
+static int regmap_spi_async_write(void *context,
+ const void *reg, size_t reg_len,
+ const void *val, size_t val_len,
+ struct regmap_async *a)
+{
+ struct regmap_async_spi *async = container_of(a,
+ struct regmap_async_spi,
+ core);
+ struct device *dev = context;
+ struct spi_device *spi = to_spi_device(dev);
+
+ async->t[0].tx_buf = reg;
+ async->t[0].len = reg_len;
+ async->t[1].tx_buf = val;
+ async->t[1].len = val_len;
+
+ spi_message_init(&async->m);
+ spi_message_add_tail(&async->t[0], &async->m);
+ if (val)
+ spi_message_add_tail(&async->t[1], &async->m);
+
+ async->m.complete = regmap_spi_complete;
+ async->m.context = async;
+
+ return spi_async(spi, &async->m);
+}
+
+static struct regmap_async *regmap_spi_async_alloc(void)
+{
+ struct regmap_async_spi *async_spi;
+
+ async_spi = kzalloc(sizeof(*async_spi), GFP_KERNEL);
+ if (!async_spi)
+ return NULL;
+
+ return &async_spi->core;
+}
+
+static int regmap_spi_read(void *context,
+ const void *reg, size_t reg_size,
+ void *val, size_t val_size)
+{
+ struct device *dev = context;
+ struct spi_device *spi = to_spi_device(dev);
+
+ return spi_write_then_read(spi, reg, reg_size, val, val_size);
+}
+
+static struct regmap_bus regmap_spi = {
+ .write = regmap_spi_write,
+ .gather_write = regmap_spi_gather_write,
+ .async_write = regmap_spi_async_write,
+ .async_alloc = regmap_spi_async_alloc,
+ .read = regmap_spi_read,
+ .read_flag_mask = 0x80,
+ .reg_format_endian_default = REGMAP_ENDIAN_BIG,
+ .val_format_endian_default = REGMAP_ENDIAN_BIG,
+};
+
+/**
+ * regmap_init_spi(): Initialise register map
+ *
+ * @spi: Device that will be interacted with
+ * @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_spi(struct spi_device *spi,
+ const struct regmap_config *config)
+{
+ return regmap_init(&spi->dev, &regmap_spi, &spi->dev, config);
+}
+EXPORT_SYMBOL_GPL(regmap_init_spi);
+
+/**
+ * devm_regmap_init_spi(): Initialise register map
+ *
+ * @spi: Device that will be interacted with
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap. The map will be automatically freed by the
+ * device management code.
+ */
+struct regmap *devm_regmap_init_spi(struct spi_device *spi,
+ const struct regmap_config *config)
+{
+ return devm_regmap_init(&spi->dev, &regmap_spi, &spi->dev, config);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_init_spi);
+
+MODULE_LICENSE("GPL");